Objective To research some parameters' influence on signal-to-noise ratio (SNR) of MR. Methods Magphan phantom was used to do experiments on 1.5T, 0.5T and 0.23T MRI. Scan parameters such as NEX, scan matrix and slice thickness were altered.Evaluate whether the change of SNR varied with parameter to be in accordance with the SNR law.Results (1) When spin echo pulse applied and NEX changed, the results of high field device A and B weren't in accordance with SNR theory, and high filed device C and low field device F were in accordance with SNR theory. When fast spin echo pulse applied and NEX changed, the result of device B was in accordance with SNR theory. (2) When scan matrix changed, measured value was lower than ideal value for little matrix, and vice versa. (3) The measured value was very closely to ideal value for little slice thickness. When slice thickness exceed 5 mm, the difference between the measured value and ideal value was significance.Conclusion Based on the SNR theory, the user of MRI should consider the running characteristic of MR system to select scan parameters.

OBJECTIVE:To establish a method for the determination of 100 pesticide residues in Morus alba. METHODS:LC-MS/MS was conducted on the column of ZORBAX Eclipse plus C18 with mobile phase of acetonitrile (containing 5% water, 0.1% formic acid,5 mmol/L ammonium formate)- water(containing 0.1% formic acid,5 mmol/L ammonium formate)(gradient elution)at a flow rate of 0.4 ml/min,column temperature was 40 ℃,injection volume was 5 μl;MS conditions:ionization source was electrospray ionization with positive ion mode,scanning mode was dynamic MRM,scanning time window was 2 min;atomiz-ing gas was nitrogen,atomizing gas pressure was 40 psi,drying gas flow rate was 5 L/min,capillary voltage was 4 000 V,and ion spray voltage was 500 V. RESULTS:The linear range of 100 pesticide residues was 2.4-150 ng/ml(r>0.990 0),recovery was 69.3%-128.2%,and the determination limit was 0.003-16 μg/kg. CONCLUSIONS:The method is simple,stable and reproduc-ible,and can be used for the determination of pesticide residues in M. alba.

Objective To explore the effect of the Jaw‐tracking with RapidArc(JT‐RapidArc) plans for upper thoracic e‐sophageal cancer .Methods Treatment planning was designed by using RapidArc and JT‐RapidArc techniques for 11 consecutive patients .The dose‐volume histogram parameters of PTV and the organs at risk ,conformity index(CI) ,heterogeneity index(HI) , low dose volume of normal tissue (B‐P ) and monitor units (MU ) were compared between the different techniques . Results Compared with the RapidArc plan ,JT‐RapidArc had increased coverage of PTV1(64) D98 and HI(P<0 .05) ,lower Dmean , D2 of PTV1(64) and PTV2(54) ,but no statistically difference in CI(P>0 .05) .Plans with JT‐RapidArc had lower Lung(V5 ,V10 , V13 ,V20 ,V30 ,Dmean ,P<0 .05) ,heart(V20 ,Dmean ,P<0 .05) ,and B‐P(V5 ,V10 ,V15 ,V20 ,V30 ,P<0 .05) ,but no significantly different in spinal cord and SC‐PRV as compared with RapidArc plans(P>0 .05) .JT‐RapidArc plans increaseed the MU by 1% (349 ± 29 vs .345 ± 16 ,P>0 .05) as compared with RapidArc plans .Conclusion All of the plans had met the requirements of clinical dosime‐try .JT‐RapidArc plans as compared with RapidArc plans ,showing better part of target coverage ,part of lung and heart and B‐P sparing ,which MU was slightly increased .

Objective To observe the expression of heat shock protein 47 (HSP47) and transforming growth factor-β2 (TGF-β2) in vitreous specimens and epiretinal membranes of patients with proliferative vitreoretinopathy diseases.Methods Vitreous specimens and epiretinal membranes were obtained from 48 patients (48 eyes) with proliferative vitreoretinopathy (PVR) and 50 patients (50 eyes) with proliferative diabetic retinopathy (PDR).Vitreous specimens and internal limiting membranes were collected from 20 patients (20 eyes) with idiopathic macular hole (IMH) as control group.The expression of HSP47 and TGF-β2 in the vitreous specimens was evaluated using enzyme linked immunosorbent assay.The expression of HSP47,TGF-β2,types Ⅰ and Ⅲ collagen in epiretinal membrane and internal limiting membrane specimens were observed for immunohistochemical staining method.The correlation between the positive expression of HSP47 and TGF-β2,types Ⅰ and Ⅲ collagen in epiretinal membrane specimens of patients with PVR and PDR were analyzed.Results The expression of HSP47 in vitreous specimens of patients with PVR,PDR and IMH were (212.35±23.32),(231.30±26.79),(171.06±28.91) pg/ml,respectively.The expression of TGF β2 in vitreous specimens of patients with PVR,PDR and IMH were (1919.96 ± 318.55),(1939.39 ± 177.57),(1194.61 ± 234.20) pg/ml,respectively.The expression of HSP47,TGF-β2 in the vitreous specimens of patients with PVR and PDR were significantly increased compared with patients with IMH and the difference was statistically significant (F=12.952,34.532;P＜0.01).The epiretinal membrane of patients with PVR and PDR showed markedly increased expression of HSP47,TGF β2,types Ⅰ and Ⅲ collagen in the cytoplasm and extracellular matrix.The expression of HSP47 and type Ⅲ collagen was negative and the expression of TGF-β2 was weakly positive and the expression of types Ⅰ collagen was positive in internal limiting membrane of patients with IMH.The expression of HSP47,TGF β2,types Ⅰ and Ⅲ collagen in the epiretinal membrane of patients with PVR and PDR were significantly increased compared with patients with IMH and the difference was statistically significant (F=13.469,18.752,12.875,20.358;P＜0.01).The expression of HSP47 was positively correlated with thepositive expression of TGF-~,types Ⅰ and Ⅲ collagen in epiretinal membrane specimens of patients withPVR (r=0.475,0.556,0.468;P＜0.05) and PDR (r=0.484,0.589,0.512;P＜0.05).Conclusions This study showed increased consistent expression of HSP47 and TGF-β2 in vitreous and epiretinal membrane specimens of patients with PVR and PDR.Both HSP47 and TGF-β2 were expressed in the cytoplasm and extracellular matrix.HSP47 and TGF-β2 may be involved in the pathological process of PDR and PVR by promoting collagen synthesis.

Objective: To investigate the application of conventional ultrasound and 16-slice CT examination in clinical diagnosis of hepatocellular carcinoma (HCC) and hepatic focal nodular hyperplasia. Methods: To choose 94 cases patients were receiving treatment in our hospital who were diagnosed as hepatic focal lesion through percutaneous biopsy of hepatocyte or histopathological examination of postoperation, and then take conventional ultrasound and 16-slice CT, respectively, to detect them. To compare and analyze the two methods in series of indicator, such as accuracy, the number of lesion size and the imageology character. Results: Conventional ultrasound diagnosis of benign tumor lesions was consistent with spiral CT results, and the difference was not statistical significance (x2=0.5556, P>0.05). The accuracy of spiral CT for hepatic carcinoma was higher than that of conventional ultrasound, and the difference was significant (x2=8.1987, P<0.05). The consistent rate of the spiral CT group with real result for micro-miniature carcinoma (the diameter less than 1 cm) was higher than that of conventional ultrasound group, and their difference was significant (x2=14.4028, P<0.05). The disappear and persist time of hepatic carcinoma patients were longer than that of non-hepatic carcinoma patients, and the difference between them was significant (t=9.7531, P<0.05). Conclusion: It is higher accuracy that 16-spiral CT can diagnose malignancy lesions in earlier stage.

Objective:To find the influence of the immuno-suppressive drug on the incidence and genotype of oral Candida albicans.Methods:51 patients using immuno-suppressive drug for 1 to 3 months were enrolled,the controls were 26 health subjects.Oral rinse samples from the patients and the controls were assessed for the growth of yeast.The liquid samples were plated on CHROMagar Candida.The isolates were defined to the species level and the genotypic subgroups by PCR method.PCR results were proved by sequencing.Results:The incidence of Candida albican in the patients and controls was 20% and 7.69% respectively.The genotype of the Candida albican in the controls is A subgroup,that in the patients included A,B and C subgroups.Conclusion:Long term of immuno-suppressive drug use can influence the genotype and incidence of oral Candida albican.

Objective: To systematically evaluate the effect of colostrum on immunoglobulin A (IgA) levels among premature infants, so as to provide the evidence for improving premature infants' health with colostrum feeding. Methods: Randomized controlled clinical trials (RCTs) or controlled clinical trials (CCTs) pertaining to the effect of colostrum and IgA levels among premature infants were retrieved in national and international databases from inception to September 30, 2022, including CNKI, Wanfang Data, PubMed and Web of Science. Standardized mean difference (SMD) was used as an effect index for meta-analysis. The robustness of the results was evaluated using sensitivity analysis, and the publication bias was evaluated using Begg's test, Egger's test and funnel plot. Results : A total of 650 publications were retrieved initially, and 10 studies were finally included, including 9 RCTs and one1 CCT, with 677 participants. Meta-analysis showed higher secretory salivary secretory IgA levels among premature infants with colostrum feeding than among controls (SMD=0.49, 95%CI: 0.08-0.89), and there were no significant differences between groups in terms of urinary secretory IgA levels (SMD=0.19, 95%CI: -0.39-0.77) or blood IgA levels (SMD=0.29, 95%CI: -0.01-0.59). Sensitivity analysis showed robustness of meta-analysis results, and no publication bias was examined. Conclusion Colostrum feeding may increase salivary secretory IgA levels among premature infants; however, it has no effect on urine salivary secretory IgA levels or blood IgA levels.

Abstract: To investigate the factors affecting lean non-alcoholic fatty liver disease (NAFLD), so as to provide the reference for the prevention and treatment of lean NAFLD. Methods: Individuals who underwent physical examination at Huzhou Central Hospital from January 1, 2023 to March 31, 2024 and had a body mass index (BMI) <23 kg/m2 was selected. Demographic information, lifestyle behaviors, dietary habits and physical examination data were collected through questionnaire surveys. Lean NAFLD was assessed using abdominal ultrasonography combined with BMI. Factors affecting lean NAFLD were analyzed by using a multivariable logistic regression model. Results: A total of 627 individuals were surveyed, with a mean BMI of (20.83±2.01) kg/m2. There were 349 males (55.66%) and 278 females (44.34%). Lean NAFLD was detected in 74 cases, with a detection rate of 11.80%. Multivariable logistic regression analysis identified BMI (OR=1.830, 95%CI: 1.165-2.869), gender (male, OR=2.615, 95%CI: 1.402-4.875), triglycerides (OR=3.062, 95%CI: 1.613-5.812), alanine aminotransferase (OR=1.587, 95%CI: 1.106-2.277), vegetable and fruit intake (150-300 g/d, OR=0.416, 95%CI: 0.230-0.752; >300 g/d, OR=0.303, 95%CI: 0.141-0.649), dairy product intake (≥300 mL/d, OR=0.369, 95%CI: 0.195-0.701) and sugared beverage intake (1-250 mL/d, OR=1.601, 95%CI: 1.071-2.393; >250 mL/d, OR=2.438, 95%CI: 1.363-4.354) as factors affecting lean NAFLD. Conclusion The risk of lean NAFLD is associated with BMI, gender, triglyceride, alanine aminotransferase, and the vegetable and fruit, dairy product and sugared beverage intake.

Objective To investigate the effect of quorum sensing autoinducer 3OC12-HSL of Pseudomonas aeruginosa on the apoptosis of Caco-2 cells and its mechanism. Methods Caco-2 cells were incubated with 3OC12-HSL for 4 h and then examined by MTT method for cytoactivities. Flow cytometry was used to analyze apoptosis rate of Caco-2 cells. Expression of apoptosis associated proteins p-p38/MAPK and NF-κB were detected by Western blot. Results After exposure to 3OC12-HSL for 4 h, cytoactivities of Caco-2 cells was reduced(P<0.05) with dose-dependent pattern, and higher dose of 3OC12-HSL leaded to increasing apoptosis rate of Caco-2 cells(P<0.05). 3OC12-HSL raised expression of apoptosis associated proteins p-p38/MAPK and NF-κB detected by Western blot. Conclusion Quorum sensing autoinducer 3OC12-HSL can effect cytoactivities of Caco-2 cells and may induce its apoptosis by enhancing the expression of p-p38/MAPK and NF-κB protein.

Objective To analysis the relationship between gestational age and perinatal outcomes in patients complicated with early onset severe preeclampsia.Methods Retrospective study was conducted on clinical documents of 221 patients with early onset severe preeclampsia( ＜ 34 weeks) who delivered after 28 gestational weeks in Peking University First Hospital from July 1999 to June 2009.Patients were divided into three groups based on gestational weeks at delivery: group Ⅰ (n = 81 ) delivered at 28 -31 weeks+6,group Ⅱ (n = 78) at 32 -33 weeks+6 and group Ⅲ (n = 62) after 34 weeks.The clinical characteristics and perinatal outcomes were compared among those three groups.Results ( 1 ) Outcome of neonates:Among 221 neonates, 13 neonates lost follow-up, including 9 in group Ⅰ , 3 in group Ⅱ, 1 in group Ⅲ.The incidence of neonatal respiratory distress syndrome ( RDS ) of 26% ( 19/72 ) in group Ⅰ were significantly higher than 7% (5/75) in group Ⅱ and 10% (6/61) in group Ⅲ (P ＜ 0.05 ).The neonatal mortality rate of (43% ,31/72) in group Ⅰ were significantly higher than 3% (2/61) in group Ⅲ and 28%(21/75) in group Ⅱ (P ＜0.05 ).The incidence of maternal complications showed no statistical difference among three groups.(2) Neonatal death analysis: all neonatal death were due to parents' give up, including 26%(8/31) in group Ⅰ, 67% (14/21)in group Ⅱ and 1/2 in group Ⅲ, which reached statistical difference(P＜0.05).Conclusions The incidence of neonatal RDS in mother with early onset severe preeclampsia was decreased if delivered after 32 weeks, and the perinatal mortality was remarkably decreased if delivered after 34 weeks.Therefore, the perinatal survival rate in women with early onset severe preeclampsia can be improved by minimizing the impact of social factors.