Objective:To explore the clinical application value of pre-breathing mode in double-low imaging of 320-slices computed tomography(CT)for pulmonary artery.Methods:A total of 100 patients who underwent CT pulmonary angiography(CTPA)for suspected pulmonary embolism(PE)in Liuzhou People's Hospital from July 2021 to September 2022 were prospectively selected as the research subjects and they were randomly divided into observation group and control group,with 50 cases in each group.The patients of the control group adopted conventional breathing mode(the breathing password was activated after reaching the threshold,and the scan was triggered after 6 s),while the patients of the observation group adopted the pre-breathing mode(the breathing password was activated after 1 or 2 seconds,and the scan was triggered after reaching the threshold).Both two groups adopted double low-technique scan of 320 slices CT.The differences in delay time,radiation dose,the points of subjective and objective image quality,and other indicators were compared between the two groups.Results:The volume CT dose index(CTDIvol),dose length product(DLP),effective dose(ED)and delay time of the observation group were significantly lower than those of the control group(t=76.230,30.225,12.282,7.088,P<0.05),respectively.The comparison of the subjective points of image qualities between the two groups indicated that there were 25 cases with 5 points,23 cases with 4 points and 2 cases with 3 points in the observation group,and there were 21 cases with 5 points,26 cases with 4 points and 3 cases with 3 points in the control group.There was no significant difference in the averagely subjective points of image qualities between two groups(P>0.05).The signal-to-noise ratio(SNR)and signal to noise ratio(CNR)of the observation group were significantly lower than those of the control group,and the noise level(SD)of the observation group was significantly higher than that of the control group(t=25.441,23.886、11.426,P<0.05),respectively.The CT values of the artery trunk of right pulmonary,artery branch of right pulmonary,artery trunk of left pulmonary and artery branch of left pulmonary in the observation group were significantly higher than those in the control group(t=2.256,2.225,2.042,2.277,P<0.05),respectively.Conclusion:The pre-breathing mode can effectively improve CTPA image quality,and reduce radiation dose and the dosage of contrast agent,which clinical application effect is significant.It is worth learning.

Objective:To analyze the use of policy tools for rural-oriented tuition-waived medical student training policy and to provide relevant suggestions for the continuous promotion of the policy.Methods:With "rural-oriented tuition-waived medical students" as the key word, the policy texts were collected and screened from government portals. Using ROTHWELL disaggregated method to build the rural order directional medical students training policy analysis framework, applying Excel 2019 software for classification and coding of policy texts.Results:A total of 13 rural-oriented medical student training policy texts were screened and obtained. The X dimension of the policy analysis framework for rural order-oriented medical student training included three policy tools, namely, supply, environment and demand, and the Y dimension included three policy objectives, namely, available, usable, and retained. In X dimension, environmental policy tools were most frequently used. In Y dimension, the "retained" target had the highest frequency of use.Conclusion:There were differences in the frequency of using policy tools for targeted medical student cultivation in different policies. The frequency of using environmental tools is higher, which highlighted the attention of the state to medical and health services. The internal structure of policy tools is unbalanced, so the configuration of supply-oriented policy tools should be optimized, and the construction of demand-oriented policy tools should be emphasized. It is suggested to continuously optimize the combination of policy tools, improve the compatibility between policy tools and rural order-oriented medical student training, and pay attention to the sustainability of policy tools.

Objective:To investigate the impact of achievement goals on the academic achievement of medical students.Methods:In May to June of 2019, an online questionnaire survey was performed for data collection, and the stratified sampling method was used for sampling. Demographic factors, Achievement Goal Scale, and Academic Achievement Scale were used in this study, and descriptive statistics, the Pearson correlation analysis, and the multivariate linear hierarchical regression analysis were performed to analyze the impact of achievement goals on the academic achievement of medical students.Results:For these medical students, the mean value of achievement-near to the goal orientation was (3.45±0.77), the mean value of achievement-dodge the goal orientation was (3.43±0.80), and the mean value of mastery goal orientation was (3.85±0.66). Achievement-near to the goal orientation had a significant positive impact on academic achievement ( β=0.336, P<0.01), and mastery goal orientation also had a significant positive impact on academic achievement ( β=0.540, P<0.01). Conclusion:The achievement goals dominated by mastery goal orientation is the most beneficial dimension for the development of medical students.

Sympathetic cues via the adrenergic signaling critically regulate bone homeostasis and contribute to neurostress-induced bone loss, but the mechanisms and therapeutics remain incompletely elucidated. Here, we reveal an osteoclastogenesis-centered functionally important osteopenic pathogenesis under sympatho-adrenergic activation with characterized microRNA response and efficient therapeutics. We discovered that osteoclastic miR-21 was tightly regulated by sympatho-adrenergic cues downstream the β2-adrenergic receptor (β₂AR) signaling, critically modulated osteoclastogenesis in vivo by inhibiting programmed cell death 4 (Pdcd4), and mediated detrimental effects of both isoproterenol (ISO) and chronic variable stress (CVS) on bone. Intriguingly, without affecting osteoblastic bone formation, bone protection against ISO and CVS was sufficiently achieved by a (D-Asp₈)-lipid nanoparticle-mediated targeted inhibition of osteoclastic miR-21 or by clinically relevant drugs to suppress osteoclastogenesis. Collectively, these results unravel a previously underdetermined molecular and functional paradigm that osteoclastogenesis crucially contributes to sympatho-adrenergic regulation of bone and establish multiple targeted therapeutic strategies to counteract osteopenias under stresses.
Adrenergic Agents/pharmacology* ; Apoptosis Regulatory Proteins/pharmacology* ; Bone Diseases, Metabolic/metabolism* ; Humans ; Liposomes ; MicroRNAs/genetics* ; Nanoparticles ; Osteoclasts ; Osteogenesis/physiology* ; RNA-Binding Proteins/pharmacology*

Liposome is an ideal drug carrier with many advantages such as excellent biocompatibility, non-immunogenicity, and easy functionalization, and has been used for the clinical treatment of many diseases including tumors. For the treatment of tumors, liposome has some passive targeting capability, but the passive targeting effect alone is very limited in improving the drug enrichment in tumor tissues, and active targeting is an effective strategy to improve the drug enrichment. Therefore, active targeting liposome drug-carriers have been extensively studied for decades. In this paper, we review the research progresses on active targeting liposome drug-carriers based on the specific binding of the carriers to the surface of tumor cells, and summarize the opportunities, challenges and future prospects in this field.
Drug Carriers/therapeutic use* ; Drug Delivery Systems ; Humans ; Liposomes/therapeutic use* ; Neoplasms/drug therapy*

Acute-on-chronic liver failure (ACLF) is a clinical disease significantly different from acute liver failure and acute decompensation of simple liver cirrhosis, and it may have acute progression to liver failure and failure of other organs. ACLF has a high short-term mortality rate and has become a disease burden worldwide. In recent years, several international associations for the study of the liver have proposed different diagnostic criteria for ACLF and published their respective consensus or review on the diagnosis and treatment of ACLF, and there are still great differences in the comprehension of chronic liver diseases, acute injury, and organ failure. At present, there are still limited data for the key links of ACLF management in China, such as liver transplantation, intensive care unit, and palliative care, and in the context of no consensus on the diagnosis of ACLF around the world, it is necessary to further strengthen the application of existing international criteria and evidence and the accumulation of evidence-based data in China.

Objective:To investigate the clinical and genetic features of early-onset Alzheimer's disease(EOAD)and the characteristics of pathogenic mutations in probands and their families.Methods:Clinical and genetic features of three EOAD probands and their family members China were analyzed and summarized.Peripheral blood of three probands and their relatives was collected and the genes were detected by second generation sequencing(Next Generation Sequencing, NGS). Pathogenic mutations carried by the probands were identified by whole exome sequencing and then verified by Sanger sequencing in the probands and their families.Furthermore, the clinical and genetic characteristics of EOAD were discussed.Results:The first case was familial EOAD, with the heterozygous mutation c. 851C>T(p.P284L)in exon 8 of PSEN1.The second was also a case of familial EOAD, involving the heterozygous deletion mutation c. 497_499del(p.Ile167del)in exon 6 of PSEN1.In the third proband, there was no family history and the c. 626G>A(G209E)mutation was found in exon 7 of the PSEN1 gene.All three patients had memory loss as their first symptom, accompanied by clinical manifestations of slow movement, abnormal gait, unclear speech, bladder and bowel incontinence, psychiatric and other symptoms.Conclusions:These mutations represent additional mutation types and clinical manifestations in EOAD patients.Examining the genetic characteristics of PSEN1 in EOAD may contribute to the understanding of the pathogenesis, genetic classification and clinical diagnosis of EOAD.

Objective:To investigate the current situation of general practitioners' occupational pressure in Heilongjiang Province, and explore its relationship with professional identity and perceived organizational support. It aims to provide references for the construction of general practitioners and the development of general medical education.Methods:The general situation questionnaire, perceived organizational support scale, occupational pressure scale, and professional identity scale were applied through network and site surveys for collecting data. A total of 288 questionnaires were collected with 263 valid questionnaires (91.3%). Pearson correction analysis and bootstrap analysis were performed for data analysis.Results:The average score of occupational pressure among general practitioners was (115.95±22.40), and the results of Pearson correction analysis showed that perceived organizational support was negatively correlated with occupational pressure ( r=-0.413, P<0.01) and positive correlation with professional identity ( r=0.587, P<0.01). There were also significant negative correlations between professional identity and occupational pressure ( r=-0.442, P<0.01). Moreover, the mediating effect showed that professional identity had a certain mediating effect on the relationship between perceived organizational support and occupational pressure (LLCI=-0.2039, ULCI=-0.0760, P<0.05). Conclusion:General practitioners' occupational pressure was at a high level, which can be reduced through improving the perceived organizational support and professional identity.

Objective To detect circulating tumor cells (CTCs) in the peripheral blood of patients with pancreatic cancer using a new nano microfluidic chip and to explore the relationship between CTCs and clinicopathological feature,postoperative recurrence and prognosis of pancreatic cancer.Methods The peripheral blood samples of 53 patients with pancreatic cancer who underwent curative resection in the second affiliated hospital of Jiaxing college of medicine were collected from January 2015 to January 2017.The CTCs from peripheral blood were detected by novel nano microfluidic chip.The cut-off value for CTCs-positive and negative groups was 1 CTC.The relationship between CTCs positive and postoperative recurrence and prognosis of pancreatic cancer were evaluated.Results The number of CTCs for 23 pancreatic cancer of 53 patients ranged from 5 to 196 per ml,and the mean number was 78.5 ± 44.7 per ml;the rate of CTCs-positive patients was 43.4％ (23/53).There were significant correlation between CTCs with vascular invasion (P =0.001),but but CTCs was not correlated with the gender,age,the presence of clinical symptoms,tumor size,pathological type,lymph metastasis and TNM stage.31 patients had tumor recurrence,and the rate of tumor recurrence was 58.5％.Among them,there were 13 cases with tumor local recurrence,10 cases with tumor distant metastasis (including liver,lung,kidney,etc.) and 8 cases with both tumor local recurrence and distant metastasis.The median recurrence free survival time of all patients was 14.0 months (13.0-17.0) and the median overall survival time was 19.0 months (15.5-24.0).The cumulative one-year and two-year recurrence free survival rate were 66.9％,12.2％ for patients with CTCs-positive and 88.3％,42.2％ for CTCs-negative patients,and the differences were statistically significant (both P ＜ 0.05).The cumulative one-year and two-year overall survival rate were 85.4％,33.6％ for patients with CTCs-positive and 96.3％,62.2％ for CTCs-negative.There was no difference in statistics in cumulative one-year overall survival rate and with a statistically significant difference in cumulative two-year overall survival rate (P =0.028).Conclusions Peripheral blood CTCs of pancreatic cancer can be effectively detected by a novel nano microfluidic chip.There were significant correlation between CTCs with vascular invasion and survival time after surgery.CTCs may be a potential prognostic indicator of the postoperative recurrence and prognosis of pancreatic cancer.

Objective To investigate the effects of chemokine like factor 1 (CKLF1) gene on the proliferative activities and osteogenic potentials of hip ligaments of ankylosing spondylitis (AS) in situ and in vitro. Methods Normal and AS hip ligament specimens were collected from 6 patients with femoral neck fracture and 4 AS patients with severe hip deformities. Ligament specimens were exposed to type Ⅱ colla-genase and obtained a single cell suspension, while phase contrast microscopy and anti-vimentin immuno- fluorescence staining (IFC) were applied to observe the cells. The specimens and fibroblasts were divided and cultured in situ and in vitro respectively, and the recombinant adeno-associated virus (rAAV)-lacZ (E. coli beta-galactosidase gene)and rAAV-hCKLF1 (human CKLF1 cDNA cloned in rAAV-lacZ in place of lacZ) were transduced for 21 days. Cell proliferation (cellularity), secretion of pro-inflammatory cytokines, expression of CKLF1 and CCR4 genes were detected by the water-soluble tetrazolium (WST-1) assay and Hoechst 33258 test (DNA content), enzyme-linked immunosorbent assay (ELISA), IFC test and fluorescent quantitative reverse transcription polymerase chain reaction (RT-PCR), respectively. Statistical analysis significance was conducted using the Student's t test and one-way analysis of variance (ANOVA) (LSD) test where appropriate. Results The second passage of normal and AS cells were positive for anti-vimentin, indicating that the cells were fibroblasts. After transducing with rAAV-hCKLF1 for 21 days, cellularity, WST-1 and Hoechst 33258 assays illustrated that CKLF1 gene transfer promoted cell proliferation (compared with the non-viral transduction and lacZ groups, F=6.98, 64.32, 115.91, P<0.05 or P<0.01). Overexpression of CKLF1 gene enhanced the secretion of pro-inflammatory cytokines (interleukin-6 and tumor necrosis factor-alpha) and the expression of bone-specific extracellular matrix proteins (osteopontin and osteocalcin) (F=34.57, 8.89, P<0.05 or P<0.01). Similar results were observed in fluorescent quantitative RT-PCR test. Conclusion Overexpression of CKLF1 promotes the proliferation of fibroblasts, the secretion of pro-inflammatory cytokines and the expression of osteogenic related target genes, suggesting that CKLF1 might be involved in the pathological ossification of AS.