ObjectiveTo explore the mechanism by which the Shenfu Xiongze prescription regulates autophagy in rats with myocardial remodeling through the adenosine monophosphate-activated protein kinase （AMPK）/mammalian target of rapamycin （mTOR） signaling pathway. MethodsA rat model of myocardial remodeling induced by isoprenaline （ISO） was established. Rats were divided into the blank group，the model group，the low-，medium-， and high-dose groups of Shenfu Xiongze prescription，and the captopril group， 6 rats in each group. Except for the blank group，the rat model of myocardial remodeling was established in the other groups by intraperitoneal injection of 2.5 mg·kg^-1 ISO for 3 consecutive weeks. At the same time of modeling， the low-，medium-， and high-dose groups of Shenfu Xiongze prescription were administered the corresponding doses of Shenfu Xiongze prescription solution （8.4，16.8，and 33.6 g·kg^-1），and the captopril group was administered captopril solution （25 mg·kg^-1）. As for the blank group and the model group， the same volume of normal saline was given. The treatment was continued for 3 weeks. Echocardiography was used to observe the cardiac structure and function，and the heart weight index was detected. Masson staining and hematoxylin-eosin （HE） staining were used to observe the pathological morphology changes of myocardial tissue. The levels of interleukin-6 （IL-6） and B-type natriuretic peptide （BNP） in serum were detected by enzyme-linked immunosorbent assay （ELISA）. The expression of type Ⅰ collagen （Collagen Ⅰ），type Ⅲ collagen （Collagen Ⅲ），and microtubule-associated protein 1 light chain 3 （LC3） proteins in myocardial tissue was determined by immunohistochemistry. Autophagy was observed by transmission electron microscopy. The mRNA expression of Collagen Ⅰ，Collagen Ⅲ，α-smooth muscle actin （α-SMA），LC3，yeast Atg6 homolog protein （Beclin-1），AMPK，and mTOR in myocardial tissue was detected by quantitative real-time polymerase chain reaction （real-time PCR）. The protein expression of Collagen Ⅰ，α-SMA，transforming growth factor-β₁ （TGF-β₁），LC3，Beclin-1，p62， phosphorylation（p）-AMPK，p-mTOR，AMPK，and mTOR was detected by Western blot. ResultsCompared with the normal group，rats in the model group exhibited significantly decreased values of ejection fraction （EF） and left ventricular fractional shortening （FS） （P<0.01）， significantly increased values of left ventricular end-diastolic diameter （LVIDd） and left ventricular end-systolic diameter （LVIDs） （P<0.01）. Additionally， the model group also showed increased degrees of inflammatory infiltration and fibrosis of myocardial tissue， significantly elevated levels of serum IL-6 and BNP （P<0.01）， significantly increased mRNA and protein levels of Collagen Ⅰ，Collagen Ⅲ，α-SMA，and mTOR （P<0.01），and markedly decreased mRNA and protein levels of LC3，Beclin-1，and AMPK （P<0.05，P<0.01）. Compared with the model group， the low-，medium-， and high-dose groups of Shenfu Xiongze prescription presented significantly elevated EF and FS values （P<0.01） and lowered LVIDd and LVIDs （P<0.05）. In these groups， the inflammation and fibrosis were alleviated significantly. They also exhibited decreased serum levels of IL-6 and BNP （P<0.01）， significantly reduced protein expression of Collagen Ⅰ， α-SMA， TGF-β₁， p62， and p-mTOR （P<0.01）， significantly decreased mRNA expression of Collagen Ⅰ， Collagen Ⅲ， α-SMA， and mTOR （P<0.01）， and significantly increased mRNA and protein levels of LC3， Beclin-1， and AMPK （P<0.05，P<0.01）. ConclusionThe Shenfu Xiongze prescription can improve the myocardial remodeling induced by ISO in rats by regulating the autophagy level，enhance cardiac function，and reduce inflammatory and fibrotic levels. This effect may be achieved through the AMPK/mTOR signaling pathway.

Objective To understand the clinical characteristics of patients with Streptococcus anginosus group(SAG)pulmonary abscess and resistance of SAG.Methods 67 patients with pulmonary abscess admitted to a hos-pital from January 2018 to May 2022 were retrospectively analyzed,clinical data of patients with SAG pulmonary abscess were analyzed,and the minimum inhibitory concentration of antimicrobial agents to 18 SAG strains was de-tected by microbroth dilution method,the carriage of resistance genes and virulence genes of SAG were detected by high-throughput sequencing technology.Results Among 67 patients with pulmonary abscess,SAG accounted for 29.9％(20/67),out of which 2 were excluded due to bacterial inactivation,and 18 patients were included for fur-ther studies.18 patients with SAG pulmonary abscess were all community acquired,with an average age of(60.9±9.1)years.There were 13(72.2％)male patients,most patients(94.4％)complicated chronic pulmonary disease,with cough(94.4％)and expectoration(88.9％)as the initial symptoms,some patients(44.4％)had chest pain,and more than half(61.1％)didn't have fever.The proportion of neutrophils,erythrocyte sedimentation rate,and C-reactive protein were mostly elevated,while procalcitonin was normal.The resistance rate of 18 SAG strains to erythromycin,clindamycin,and tetracycline was＞65％,out of which 14 strains carried resistance gene ermB,13 strains carried resistance gene tetM,and 1 strain carried both resistance gene msrD and mefA.18 SAG strains were detected virulence gene psaA,out of which 3 strains were detected virulence gene nan A.Conclusion SAG is an im-portant pathogen that causes pulmonary abscess,and the patients'complications are mainly chronic pulmonary di-seases,with non-specific clinical manifestations;Most strains carry ermB and tetM genes,mediating resistance to macrolides,lincosamides,and tetracyclines.

Objective:To investigate the effects of Shenfu Xiongze Prescription on myocardial fibrosis induced by isoproterenol (ISO) in rats.Methods:SD rats were divided into blank control group, model group, and Shenfu Xiongze Prescription low-, medium-, and high-dosage groups according to random number table method. with 7 rats in each group. Except for the blank control group, the other groups were induced to form myocardial fibrosis in rats by intraperitoneal injection of isoprenaline. Shenfu Xiongze Prescription low-, medium-, and high-dosage groups were administered Shenfu Xiongze Prescription solution at dosages of 8.4, 16.8, and 33.6 g/kg, respectively, while the blank control group and the model group were given the same volume of normal saline for gavage, once a day, for consecutive 3 weeks. The heart structure and function were observed by echocardiography, the levels of BNP and IL-6 in serum were detected by ELISA, the pathological changes of myocardial tissue were observed by HE and Masson staining, and the expressions of TGF-β1 and α-SMA proteins in myocardial tissue were detected by Western blot.Results:Compared with the model group, the EF and FS values of Shenfu Xiongze Prescription in all dosage groups decreased ( P<0.01), the LVIDd and LVIDs increased ( P<0.05 or P<0.01), and the expressions of TGF-β1 and α-SMA proteins in myocardial tissue decreased ( P<0.01 or P<0.05); the levels of BNP and IL-6 in serum of the Shenfu Xiongze Prescription medium and high-dosage groups decreased ( P<0.05 or P<0.01), while the level of IL-6 in the low-dosage group decreased ( P<0.01). Conclusion:Shenfu Xiongze Prescription can inhibit rat myocardial fibrosis induced by isoprenaline, improve rat cardiac function, and its mechanism may be related to reducing inflammation in the heart and down-regulating the expressions of TGF-β1 and α-SMA proteins.

Objective:To investigate the association between serum IgG concentration and renal prognosis in patients with IgA nephropathy (IgAN).Methods:It was a multi-center retrospective cohort study, patients with biopsy proven primary IgAN who were recorded in the Chinese IgA Nephropathy Information Registration System between April 1996 and September 2018 were included. Exclusion criteria were: (1) age <18 years; (2) <8 glomeruli in biopsy specimens; (3) estimated glomerular filtration rate (eGFR) <15 ml·min -1·(1.73 m 2) -1 at biopsy; (4) missing baseline serum IgG values; (5) incomplete follow-up data; (6) follow-up duration <12 months. Enrolled patients were divided into 3 groups according to the baseline tertiles of serum IgG: ≤9.50 g/L (G1 group), 9.51-11.99 g/L (G2 group), and ≥12.00 g/L (G3 group). Clinical, and pathological parameters were compared across groups. The endpoint events were defined as doubled serum creatinine level from baseline, or end-stage renal disease (ESRD). Results:A total of 1 976 IgAN patients were included in this study, 631 were in G1 group, 664 in G2 group, and 681 in G3 group. The comparison of baseline clinical data showed that there were statistically significant differences among the three groups in terms of gender, age, microscopic hematuria, edema, body mass index, systolic blood pressure, diastolic blood pressure, hemoglobin, serum creatinine, eGFR, 24-hour urine protein quantity, blood uric acid, blood albumin, serum IgA, serum IgM, the proportion of using immunosuppressants, and the proportion of using glucocorticoids (all P<0.05). In terms of pathology, the higher the serum IgG concentration, the relatively less severe the overall renal pathological damage. The results of univariate Cox regression analysis showed that gender, systolic blood pressure, diastolic blood pressure, hemoglobin, serum creatinine, eGFR, 24-hour urine protein quantity, total protein, serum albumin, globulin, serum IgG, Oxford renal pathological classification, glomerular sclerosis ratio, and glomerular IgM deposition were all associated with the occurrence of renal endpoint events (all P<0.05). Based on clinical practice and previous studies, after adjusting for gender, age, systolic blood pressure, diastolic blood pressure, eGFR, 24-hour urine protein quantity, body mass index, Oxford renal pathological classification, glomerular sclerosis ratio, and the use of renin-angiotensin-aldosterone system inhibitors, glucocorticoids, and immunosuppressants, multivariate Cox regression analysis showed that as a continuous variable, the baseline serum IgG level ( HR=0.91, 95% CI 0.87-0.96) was independently associated with the risk of renal endpoint events in IgAN patients; as a categorical variable, with serum IgG ≤ 9.50 g/L as the reference, serum IgG 9.51-11.99 g/L and serum IgG ≥ 12.00 g/L were independent factors for the occurrence of renal endpoint events in IgAN patients ( HR=0.69, 95% CI 0.49-0.96, P=0.027; HR=0.50, 95% CI 0.34-0.74, P<0.001). During a median follow-up of 33(21, 53) months started from the date of renal biopsy and continued until December 31, 2019, the median follow-up duration was 33 (21, 53) months, and a total of 232 patients (11.74%) reached the composite endpoint. Kaplan-Meier survival analysis showed that the higher the serum IgG concentration in patients with IgAN, the higher their cumulative renal survival rate (Log-rank test, χ2=47.176, P<0.001). Conclusion:The higher level of serum IgG at diagnosis is associated with better clinicopathologic features and renal outcomes, and may portend better renal survival in IgAN patients.

Objective To understand the clinical characteristics of patients with Streptococcus anginosus group(SAG)pulmonary abscess and resistance of SAG.Methods 67 patients with pulmonary abscess admitted to a hos-pital from January 2018 to May 2022 were retrospectively analyzed,clinical data of patients with SAG pulmonary abscess were analyzed,and the minimum inhibitory concentration of antimicrobial agents to 18 SAG strains was de-tected by microbroth dilution method,the carriage of resistance genes and virulence genes of SAG were detected by high-throughput sequencing technology.Results Among 67 patients with pulmonary abscess,SAG accounted for 29.9％(20/67),out of which 2 were excluded due to bacterial inactivation,and 18 patients were included for fur-ther studies.18 patients with SAG pulmonary abscess were all community acquired,with an average age of(60.9±9.1)years.There were 13(72.2％)male patients,most patients(94.4％)complicated chronic pulmonary disease,with cough(94.4％)and expectoration(88.9％)as the initial symptoms,some patients(44.4％)had chest pain,and more than half(61.1％)didn't have fever.The proportion of neutrophils,erythrocyte sedimentation rate,and C-reactive protein were mostly elevated,while procalcitonin was normal.The resistance rate of 18 SAG strains to erythromycin,clindamycin,and tetracycline was＞65％,out of which 14 strains carried resistance gene ermB,13 strains carried resistance gene tetM,and 1 strain carried both resistance gene msrD and mefA.18 SAG strains were detected virulence gene psaA,out of which 3 strains were detected virulence gene nan A.Conclusion SAG is an im-portant pathogen that causes pulmonary abscess,and the patients'complications are mainly chronic pulmonary di-seases,with non-specific clinical manifestations;Most strains carry ermB and tetM genes,mediating resistance to macrolides,lincosamides,and tetracyclines.

Objective:To evaluate the effect of an electronic balance aid in balance rehabilitation training for patients with acute peripheral vestibular injury by comparing the outcomes of medication-only treatment and medication combined with vestibular rehabilitation using an electronic balance aid.Methods:This was a randomized controlled trial. The study subjects included 98 patients (40 males and 58 females, aged 25-69 years) diagnosed with idiopathic sudden sensorineural hearing loss (ISSNHL) with vertigo or vestibular neuritis, who were treated in the Department of Otorhinolaryngology-Head and Neck Surgery of Tianjin First Central Hospital from November 2022 to November 2023. All patients were randomly divided into the experimental group and the control group at a 1∶1 ratio using the sealed envelope method. Control group (conventional drug treatment): Patients received medication treatment for 2 weeks, including betahistine mesilate tablets, vitamin B1 tablets, methylcobalamin tablets, ginkgo biloba tablets, diphenhydramine hydrochloride injection (within 3 days of onset), metoclopramide hydrochloride injection, and glucocorticoids. Experimental group (conventional drug treatment+device training): On the basis of the same medication treatment as the control group, patients received vestibular rehabilitation training using an electronic balance aid (20 minutes per session, once a day,≥5 days per week, for a total of 2 weeks). SPSS software was used to compare the total scores of the Dizziness Handicap Inventory (DHI), the total scores of the Sensory Organization Test (SOT), and sensory analysis indicators between the two groups before and after treatment.Results:After treatment, vertigo symptoms significantly improved in both groups. DHI: The total DHI score in the control group decreased from 77.9±1.8 before treatment to 20.2±2.3 after treatment ( P<0.001). In the experimental group, the total DHI score decreased from 73.5±2.1 before treatment to 8.6±0.9 after treatment ( P<0.001). The difference in total DHI scores between the two groups after treatment was statistically significant, with the experimental group showing a lower score ( t=-4.616, P<0.001). The improvement in DHI scores was also more pronounced in the experimental group compared to the control group ( t=2.004, P=0.048). SOT: The total SOT score in the control group increased from 52.90±0.95 before treatment to 73.3±1.1 after treatment ( P<0.001). In the experimental group, the total SOT score increased from 54.9±0.8 before treatment to 83.5±0.9 after treatment ( P<0.001). The difference in total SOT scores between the two groups after treatment was statistically significant, with the experimental group showing a higher score ( t=7.104, P<0.001). The improvement in SOT scores was also more pronounced in the experimental group compared to the control group ( t=6.532, P<0.001). Sensory Analysis Indicators Proprioception (SOM): In the experimental group, the proprioception score significantly increased after treatment compared with before treatment ( t=-2.338, P=0.029), while, there was no statistically significant difference in the proprioception score of the control group before and after treatment ( P=0.537). Before treatment, there were no statistically significant differences in visual, vestibular, or visual dependence scores between the two groups (all P>0.05). After treatment, the visual, vestibular, and visual dependence scores of both groups significantly increased compared with those before treatment (all P<0.05); moreover, the post-treatment visual, vestibular, and visual dependence scores of the experimental group were significantly higher than those of the control group (all P<0.05). Conclusion:Compared with medication-only treatment, the combination of an electronic balance aid and medication for the treatment and rehabilitation training of patients with acute peripheral vestibular injury can significantly improve the therapeutic effect in the short term.

Objective:To evaluate the effect of an electronic balance aid in balance rehabilitation training for patients with acute peripheral vestibular injury by comparing the outcomes of medication-only treatment and medication combined with vestibular rehabilitation using an electronic balance aid.Methods:This was a randomized controlled trial. The study subjects included 98 patients (40 males and 58 females, aged 25-69 years) diagnosed with idiopathic sudden sensorineural hearing loss (ISSNHL) with vertigo or vestibular neuritis, who were treated in the Department of Otorhinolaryngology-Head and Neck Surgery of Tianjin First Central Hospital from November 2022 to November 2023. All patients were randomly divided into the experimental group and the control group at a 1∶1 ratio using the sealed envelope method. Control group (conventional drug treatment): Patients received medication treatment for 2 weeks, including betahistine mesilate tablets, vitamin B1 tablets, methylcobalamin tablets, ginkgo biloba tablets, diphenhydramine hydrochloride injection (within 3 days of onset), metoclopramide hydrochloride injection, and glucocorticoids. Experimental group (conventional drug treatment+device training): On the basis of the same medication treatment as the control group, patients received vestibular rehabilitation training using an electronic balance aid (20 minutes per session, once a day,≥5 days per week, for a total of 2 weeks). SPSS software was used to compare the total scores of the Dizziness Handicap Inventory (DHI), the total scores of the Sensory Organization Test (SOT), and sensory analysis indicators between the two groups before and after treatment.Results:After treatment, vertigo symptoms significantly improved in both groups. DHI: The total DHI score in the control group decreased from 77.9±1.8 before treatment to 20.2±2.3 after treatment ( P<0.001). In the experimental group, the total DHI score decreased from 73.5±2.1 before treatment to 8.6±0.9 after treatment ( P<0.001). The difference in total DHI scores between the two groups after treatment was statistically significant, with the experimental group showing a lower score ( t=-4.616, P<0.001). The improvement in DHI scores was also more pronounced in the experimental group compared to the control group ( t=2.004, P=0.048). SOT: The total SOT score in the control group increased from 52.90±0.95 before treatment to 73.3±1.1 after treatment ( P<0.001). In the experimental group, the total SOT score increased from 54.9±0.8 before treatment to 83.5±0.9 after treatment ( P<0.001). The difference in total SOT scores between the two groups after treatment was statistically significant, with the experimental group showing a higher score ( t=7.104, P<0.001). The improvement in SOT scores was also more pronounced in the experimental group compared to the control group ( t=6.532, P<0.001). Sensory Analysis Indicators Proprioception (SOM): In the experimental group, the proprioception score significantly increased after treatment compared with before treatment ( t=-2.338, P=0.029), while, there was no statistically significant difference in the proprioception score of the control group before and after treatment ( P=0.537). Before treatment, there were no statistically significant differences in visual, vestibular, or visual dependence scores between the two groups (all P>0.05). After treatment, the visual, vestibular, and visual dependence scores of both groups significantly increased compared with those before treatment (all P<0.05); moreover, the post-treatment visual, vestibular, and visual dependence scores of the experimental group were significantly higher than those of the control group (all P<0.05). Conclusion:Compared with medication-only treatment, the combination of an electronic balance aid and medication for the treatment and rehabilitation training of patients with acute peripheral vestibular injury can significantly improve the therapeutic effect in the short term.

Objective:To investigate the association between serum IgG concentration and renal prognosis in patients with IgA nephropathy (IgAN).Methods:It was a multi-center retrospective cohort study, patients with biopsy proven primary IgAN who were recorded in the Chinese IgA Nephropathy Information Registration System between April 1996 and September 2018 were included. Exclusion criteria were: (1) age <18 years; (2) <8 glomeruli in biopsy specimens; (3) estimated glomerular filtration rate (eGFR) <15 ml·min -1·(1.73 m 2) -1 at biopsy; (4) missing baseline serum IgG values; (5) incomplete follow-up data; (6) follow-up duration <12 months. Enrolled patients were divided into 3 groups according to the baseline tertiles of serum IgG: ≤9.50 g/L (G1 group), 9.51-11.99 g/L (G2 group), and ≥12.00 g/L (G3 group). Clinical, and pathological parameters were compared across groups. The endpoint events were defined as doubled serum creatinine level from baseline, or end-stage renal disease (ESRD). Results:A total of 1 976 IgAN patients were included in this study, 631 were in G1 group, 664 in G2 group, and 681 in G3 group. The comparison of baseline clinical data showed that there were statistically significant differences among the three groups in terms of gender, age, microscopic hematuria, edema, body mass index, systolic blood pressure, diastolic blood pressure, hemoglobin, serum creatinine, eGFR, 24-hour urine protein quantity, blood uric acid, blood albumin, serum IgA, serum IgM, the proportion of using immunosuppressants, and the proportion of using glucocorticoids (all P<0.05). In terms of pathology, the higher the serum IgG concentration, the relatively less severe the overall renal pathological damage. The results of univariate Cox regression analysis showed that gender, systolic blood pressure, diastolic blood pressure, hemoglobin, serum creatinine, eGFR, 24-hour urine protein quantity, total protein, serum albumin, globulin, serum IgG, Oxford renal pathological classification, glomerular sclerosis ratio, and glomerular IgM deposition were all associated with the occurrence of renal endpoint events (all P<0.05). Based on clinical practice and previous studies, after adjusting for gender, age, systolic blood pressure, diastolic blood pressure, eGFR, 24-hour urine protein quantity, body mass index, Oxford renal pathological classification, glomerular sclerosis ratio, and the use of renin-angiotensin-aldosterone system inhibitors, glucocorticoids, and immunosuppressants, multivariate Cox regression analysis showed that as a continuous variable, the baseline serum IgG level ( HR=0.91, 95% CI 0.87-0.96) was independently associated with the risk of renal endpoint events in IgAN patients; as a categorical variable, with serum IgG ≤ 9.50 g/L as the reference, serum IgG 9.51-11.99 g/L and serum IgG ≥ 12.00 g/L were independent factors for the occurrence of renal endpoint events in IgAN patients ( HR=0.69, 95% CI 0.49-0.96, P=0.027; HR=0.50, 95% CI 0.34-0.74, P<0.001). During a median follow-up of 33(21, 53) months started from the date of renal biopsy and continued until December 31, 2019, the median follow-up duration was 33 (21, 53) months, and a total of 232 patients (11.74%) reached the composite endpoint. Kaplan-Meier survival analysis showed that the higher the serum IgG concentration in patients with IgAN, the higher their cumulative renal survival rate (Log-rank test, χ2=47.176, P<0.001). Conclusion:The higher level of serum IgG at diagnosis is associated with better clinicopathologic features and renal outcomes, and may portend better renal survival in IgAN patients.

Objective:To investigate the ultrasonographic features of medullary thyroid carcinomas (MTCs) of different sizes and supply valid information for separating MTCs from papillary thyroid carcinomas (PTCs).Methods:There were 87 patients with MTC and 220 patients with PTC detected by ultrasonography and confirmed by pathology at Tianjin Medical University Cancer Institute and Hospital from June 2018 to March 2022. Nodules were divided into the large nodule group (the maximum diameter of the tumor was＞1 cm) and the small nodule group (the maximum diameter of the tumor was ≤1 cm). There were 97 cases in the small nodule group, including 28 cases of MTC and 69 cases of PTC. There were 210 cases in the large nodule group, including 59 cases of MTC and 151 cases of PTC. After stratification by thyroid nodules, ultrasonographic features of thyroid nodules and metastatic lymph nodes, preoperative serum calcitonin (CT) and carcinoembryonic antigen (CEA) levels were compared between MTC and PTC patients.Results:In the small nodule group, the proportion of MTCs exhibiting hypoecho, smooth margins, and having blood flow signals was higher than that of PTCs, with statistically significant differences (all P＜0.05). In the large nodule group, the proportion of MTCs showing cystic solidity, hypoecho, smooth margins, blood flow, and the type Ⅳvascular distribution was higher than PTCs, and the difference of calcification type between them was also statistically significant (all P＜0.05). In contrast, the differences in the number of lesions and aspect ratio between MTCs and PTCs were not statistically significant regardless of nodule size (all P＞0.05). In the small nodule group,6 metastatic lymph nodes of medullary thyroid carcinoma (LNM-MTC) and 11 metastatic lymph nodes of papillary thyroid carcinoma (LNM-PTC) were correctly diagnosed by ultrasound, respectively. The diagnostic compliance rate of ultrasound was 78.6% (22/28) and 78.3% (54/69), respectively, with no statistically significant difference ( P=0.973). In the large nodule group, 28 LNM-MTC and 11 LNM-PTC were correctly diagnosed by ultrasound, respectively. The diagnostic compliance of ultrasound was 88.1% (52/59) and 73.5% (111/151), respectively, which was statistically significant ( P=0.022). Among them, 82.1% of LNM-MTC and 56.6% of LNM-PTC showed abnormal blood flow signals, with a statistically significant difference ( P=0.016). There were significant differences in preoperative serum CT and CEA levels of different sizes of MTCs (all P＜0.05). Conclusions:Different sizes of MTCs require diverse demonstrative criteria. Abnormal blood flow signal is of great significance in the diagnosis of LNM-MTC. Within the absence of ultrasonic characteristics, preoperative serum CT test can provide confidence for the diagnosis of MTC.

Objective:To investigate the ultrasonographic features of medullary thyroid carcinomas (MTCs) of different sizes and supply valid information for separating MTCs from papillary thyroid carcinomas (PTCs).Methods:There were 87 patients with MTC and 220 patients with PTC detected by ultrasonography and confirmed by pathology at Tianjin Medical University Cancer Institute and Hospital from June 2018 to March 2022. Nodules were divided into the large nodule group (the maximum diameter of the tumor was＞1 cm) and the small nodule group (the maximum diameter of the tumor was ≤1 cm). There were 97 cases in the small nodule group, including 28 cases of MTC and 69 cases of PTC. There were 210 cases in the large nodule group, including 59 cases of MTC and 151 cases of PTC. After stratification by thyroid nodules, ultrasonographic features of thyroid nodules and metastatic lymph nodes, preoperative serum calcitonin (CT) and carcinoembryonic antigen (CEA) levels were compared between MTC and PTC patients.Results:In the small nodule group, the proportion of MTCs exhibiting hypoecho, smooth margins, and having blood flow signals was higher than that of PTCs, with statistically significant differences (all P＜0.05). In the large nodule group, the proportion of MTCs showing cystic solidity, hypoecho, smooth margins, blood flow, and the type Ⅳvascular distribution was higher than PTCs, and the difference of calcification type between them was also statistically significant (all P＜0.05). In contrast, the differences in the number of lesions and aspect ratio between MTCs and PTCs were not statistically significant regardless of nodule size (all P＞0.05). In the small nodule group,6 metastatic lymph nodes of medullary thyroid carcinoma (LNM-MTC) and 11 metastatic lymph nodes of papillary thyroid carcinoma (LNM-PTC) were correctly diagnosed by ultrasound, respectively. The diagnostic compliance rate of ultrasound was 78.6% (22/28) and 78.3% (54/69), respectively, with no statistically significant difference ( P=0.973). In the large nodule group, 28 LNM-MTC and 11 LNM-PTC were correctly diagnosed by ultrasound, respectively. The diagnostic compliance of ultrasound was 88.1% (52/59) and 73.5% (111/151), respectively, which was statistically significant ( P=0.022). Among them, 82.1% of LNM-MTC and 56.6% of LNM-PTC showed abnormal blood flow signals, with a statistically significant difference ( P=0.016). There were significant differences in preoperative serum CT and CEA levels of different sizes of MTCs (all P＜0.05). Conclusions:Different sizes of MTCs require diverse demonstrative criteria. Abnormal blood flow signal is of great significance in the diagnosis of LNM-MTC. Within the absence of ultrasonic characteristics, preoperative serum CT test can provide confidence for the diagnosis of MTC.