GDNF-induced seminomatous tumours in mouse--an experimental model for human seminomas?

Glial-cell-line-derived neurotrophic factor (GDNF) is a distant member of the transforming growth factor superfamily. It binds to and activates a receptor complex consisting of GFR-alpha1 and Ret receptor tyrosine kinase. In testis, GDNF is expressed by Sertoli cells. We have shown by transgenic loss- and gain-of-function mouse models that GDNF regulates the cell fate decision of undifferentiated spermatogonia. In the GDNF +/- mice, the spermatogonia differentiate in excess leading to the depletion of germ cells. In the mice overexpressing GDNF in testes, undifferentiated spermatogonia accumulate in the tubules, no sperm is produced, and the mice are infertile. After a year, the GDNF overexpressing mice frequently (89%) develop testicular tumours, and most of them are bilateral (56%). All these tumours show the same histological pattern. They are composed of round spermatogonial/gonocytic cells with only a scant cytoplasm. The tumours are locally invasive but do not metastasise. They express germ line markers, are positive for alkaline phosphatase, and aneuploid with a triploid peak. Thus, by several histological, molecular, and histochemical characteristics, the GDNF-induced tumours mimic classical seminomas in men, but the precursor lesions are apparently different in mouse and man.     

Longitudinal Examination of Prenatal Tobacco Switching Behaviors and Birth Outcomes,Including Electronic Nicotine Delivery System (ENDS) and Dual Use

Maternal and Child Health Journal - In the US, approximately 8% of pregnant women smoke, and 5–11.9% currently use ENDS products. The health effects of ENDS use are debated; however, most...     

微乳液反应法制备磺胺嘧啶银均匀微晶及其最佳处方评价

目的：应用微乳液反应法制备磺胺嘧啶银均匀微晶,均匀制得的微晶的粒径大小约为2～4um,均匀微晶的结晶性好,纯度高。用均匀设计方法优化条件,制备的均匀的微晶平均粒径大小为2.09um,实验结果达到预测结果要求。结论：用微乳液反应法能获得磺胺嘧啶银均匀微晶。     

滕州市致病性弧菌检测报告

报道了1995年以来,滕州市致病性弧菌种类、分,布等病原学检测情况。共检疑似霍乱病人粪便1562人份,检出致病性弧菌127株,检出率为8．13％,其中非01群霍乱弧菌居首位83株占65．35％,其次为麦氏弧菌13株占10．4％,溶藻弧菌11株,河弧菌9株,副溶血弧菌6株,弗尼期弧菌5株。83株非01群霍乱弧菌可分型占61株,分布8个血清型,定型率为73．49％,127株致病性弧菌产类霍乱肠毒素（G）47株占37．00％,以非01群霍乱弧菌产生类CT所占比例为最高,从而说明它在毒力和致病性方面占有重要地位。     

心肌梗塞大鼠心室胶原生化改建与心脏肾素—血管紧张素系统的关系

目的 研究心肌梗塞（MI）后心室胶原生化改建与心脏肾素-血管紧张素系统（RAS）的关系。方法 采用放射免疫等方法动态观测了大鼠MI后3、15及42天左、右心室胶原含量、总量和血管紧张素Ⅱ(AngⅡ）含量以及血浆AngⅡ含量的变化,结果 血浆AngⅡ含量仅在MI后3天有一过性升高;MI鼠左、右心室AngⅡ含量以及血浆AngⅡ含量的变化。结果 血浆AngⅡ含量仅在MI后3天有一过性升高;MI鼠左、右心室AngⅡ含量于3天时就明显升高,此后一直保持在3天时水平,MI后左、右心室胶原基质均发生了生化改建,除右心室胶原生化建建稍滞后于其AngⅡ的变化外,左、右心室的胶原生化改建与其心肌AngⅡ的变化形式基本一致。结论 MI后心脏RAS被明显激活;心肌AngⅡ在心肌胶原生化改建的过程中可能起着重要的作用。而且其作用不依赖于循环RAS。     

口腔固定修复学临床前期实习中的问题与对策

本文总结了北京大学口腔医学院3届八年制口腔医学专业学生口腔固定修复学临床前期实习教学的经验,针对实习中出现的典型问题进行了分析,采取了相应的对策和方法,取得了良好的效果.     

Approach selection and outcomes of craniopharyngioma resection: a single-institute study

Neurosurgical Review - Since there are many approaches for successful craniopharyngioma resection, how to choose a suitable approach remains problematic. The aim of this study was to summarize...     

中药解郁胶囊治疗老年抑郁症的临床疗效观察

目的：观察中药解郁胶囊对老年抑郁症的临床疗效和安全性。方法：选取2020年11月至2021年12月甘肃中医药大学附属医院住院或门诊患者200例作为研究对象,按照纳入标准最终产生研究观察对象100例,健康对照组来自我院组织的年龄在60~80岁的健康体检的老年人100例。观察组中男37例,女63例,对照组中男43例,女57例。对照组采取常规治疗,观察组采取中医综合疗法治疗。对2组患者治疗前后减分情况、中医证候分析、服药及依从情况、不良反应及抑郁焦虑因子等无创性指标的影响。结果：对老年抑郁症的治疗效果主要从汉密尔顿抑郁量表减分情况及证候减分率体现,2组经过12个月中药和抗抑郁综合治疗,中医证候量表减分率（8.2±3.1）和（7.8±3.2）,比对照组的（8.8±3）与（8.4±3.6）,P值为0.001 6和0.001 3,治疗前后均有明显变化,差异有统计学意义（P<0.05）,中医证候量表减分率比较,差异有统计学意义（P<0.05）,从服药后出现的不良反应来看,中医综合观察组应明显低于对照观察组,差异有统计学意义（P<0.05）。从中医组治疗患者的依从性分析,差异有统计学意义（P<0.05）。结论：中药解郁胶囊与中医综合治疗患者治疗效果显著,依从性更佳。     

基于肠道菌群和代谢组学研究化滞柔肝颗粒治疗非酒精性脂肪肝的作用机制

目的 探讨化滞柔肝颗粒治疗非酒精性脂肪肝（nonalcoholic fatty liver disease,NAFLD）的作用机制。方法 高脂饮食饲养8周构建大鼠NAFLD模型,化滞柔肝颗粒ig给药4周。半自动生化分析仪测定大鼠血脂相关指标;油红O染色观察肝脏组织病理变化;Illumina Miseq测序平台对V3～V4可变区进行扩增和测序,超高效液相色谱串联质谱（UPLCMS/MS）开展血浆代谢组学研究,并结合Spearman进行肠道菌群与代谢组学之间的关联分析。结果 与模型组相比,化滞柔肝颗粒中、高剂量组可显著降低大鼠体质量（P<0.05、0.01）和血清总胆固醇（totalcholesterol,TC）、三酰甘油（triacylglycerol,TG）水平（P<0.01）,升高高密度脂蛋白（high-density lipoprotein cholesterol,HDL-C）水平（P<0.05、0.01）。此外,化滞柔肝颗粒高剂量组还可显著降低大鼠低密度脂蛋白（low-density lipoprotein cholesterol,LDL-C）水平（P<0...