玻璃体视网膜手术病因分析

目的：研究玻璃体视网膜手术的主要致病。方法：对449例玻璃体视网膜手术做回顾性分析,男243例,女206例,术前视力光感－0．2;平均病史11．6月,手术采用三切口闭合式玻璃体切割术,结果：449例诊断明确,与术前诊断符合率为80．6％,病因中视网膜血管性疾病114例,占25．39％,眼外伤85例,占18．93％,糖尿病视网膜病变82例,占18．26％,黄斑部病变41例,占9．13％,孔源性视网膜脱离39例,占8．69％,眼内炎25例,占5．57％,结论：玻璃体视网膜手术正走向成熟,其适应证逐渐扩展,已成为治疗眼后段疾病的重要手段。     

胸椎间盘突出症的外科治疗进展

胸椎间盘突出症在临床上较为少见,在所有椎间盘突出症中所占比例不足1％。近年来,随着对本病成像认识的不断深入及影像学诊断技术的不断发展,尤其是磁共振(MRI)检查应用的日益广泛,日前本病的诊断率有上升的趋势。 胸椎间盘突出症的临床表现较为复杂且缺乏特异性,临床上容易发生误诊或漏诊。一旦发病,脊髓压迫症状多呈进行性发展,且多伴有马尾神     

闭合性腹部损伤428例临床分析

闭合性腹部损伤是腹部外科的常见急症 ,并发症发生率及死亡率较高 ,因此早期诊断和及时处理至关重要。我院自1991年 1月至 2 0 0 1年 1月共收治闭合性腹部损伤 42 8例 ,就其早期诊断和治疗分析如下。1　临床资料1.1　一般资料　本组 42 8例 ,男 346例 ,女 82例 ,年龄 6～ 72岁 ,其中 2 0～ 45岁 2 6 5例 ,占 6 2 %。致伤原因 :车祸伤 184例 ,坠落伤 81例 ,挤压伤 6 4例 ,打击伤 6 8例 ,跌伤 31例。损伤类型 :单纯腹部损伤占 72 % (30 8/ 42 8) ,其中单一脏器损伤占 85 % (2 6 1/ 30 8) ,两个以上脏器损伤占 15 % (47/ 30 8) ;两个或以上部位…     

阿帕替尼和替吉奥对结肠癌治疗效果的系统评价和Meta分析

目的通过系统评价和Meta分析探讨阿帕替尼与替吉奥对比治疗结肠癌的有效性和安全性。方法以"阿帕替尼""替吉奥""结肠癌""等为中文关键词,以"Apatinib""Tegafur""Colon cancer"等为英文关键词,检索PubMed,Cochrane Library,Embase,Web of Science,中国知网、中国生物医学文献服务系统、维普数据库、万方数据知识服务平台,时间限制在从建库到2020年12月。评价阿帕替尼和替吉奥对结肠癌的总体疗效,结肠癌进展和无进展生存期的差异。研究采用RevMan 5.3软件进行Meta分析。结果Meta分析结果显示,阿帕替尼与替吉奥对结肠癌的疗效相比,部分缓解+稳定的差异没有统计学意义(RR=1.10,95%CI,0.71~1.71,P=0.640),在结肠癌进展方面的差异没有统计学意义(RR=0.51,95%CI:0.28~1.32,P=0.205),在无进展生存期方面阿帕替尼组大于替吉奥组,差异具有统计学意义(SMD=0.90,95%CI;0.42~1.37,P<0.0001)。结论相较于替吉奥,阿帕替尼用于治疗结肠癌患者能明显延长无进展生存期,总体生存效益有所提高。     

中国9个省（自治区、直辖市）小学生户外时间对近视发生影响的队列研究

目的 探索户外时间对小学生近视发生的影响,并评估其在不同年级学生中的差异,为预防近视相关政策制定提供依据。方法 本研究基于队列研究设计,在2019年调查了江苏、上海、福建、山西、河南、湖南、甘肃、重庆、广西9个省（自治区、直辖市）6 046名1~5年级小学生,现场对其近视情况进行检查,并在2020年对该群体再次进行随访,现场检测近视发生情况,并在2020年视力测量后一周内对近视相关行为进行问卷调查。采用χ²检验、Cochran-Armitage趋势检验比较组间差异,采用Cox比例风险回归模型检验户外时间与近视发生的关系。结果 在2020年,基线时为1~5年级的小学生近视发生率为27.5%,其中,1~2年级小学生近视发生率为23.0%,3~5年级小学生近视发生率为31.7%。控制协变量后,在1~2年级小学生中,平均每天户外时间≥1 h学生近视发生风险是平均每天户外时间<1 h学生的0.76倍（95%CI：0.62~0.93,P=0.008）;而对于3~5年级小学生,平均每天户外时间≥3 h才对近视发生有显著保护作用,其近视发生风险是平均每天户外时间<3 h学生的0.75倍（95%CI：0.61~0.93,P=0.007）。结论 1~2年级小学生平均每天达到1 h户外时间可以降低近视发生率,而3~5年级小学生平均每天需达到3 h户外时间可能才会有效降低近视发生率。因此,针对不同年级小学生预防近视的户外时间推荐应有差异,年级越高,户外时间相应增加,降低其近视发生率。但同时,还要关注其他因素对近视的作用,采用综合手段防控近视的发生。     

Immunogenicity,safety and reactogenicity of ROTAVAC® in healthy infants aged 6–8 weeks in Vietnam

BackgroundROTAVAC® is derived from human 116E rotavirus (RV) neonatal strain. In this study, we evaluated the immunogenicity, safety and reactogenicity of ROTAVAC® in Vietnam.MethodWe conducted a phase IV clinical trial in healthy infants aged 6–8 weeks using the complete regimen of ROTAVAC® with three doses. Serum anti-RV IgA was measured by enzyme-linked immunosorbent assay to assess the geometric mean concentration in infants who received the complete regimen of the vaccine.ResultsA total of 360 participants were enrolled in this clinical trial. The mean age ± standard deviation at enrollment was 6.9 ± 0.6 weeks. The anti-RV IgA titer was 4.01 ± 3.74 mg/ml pre-vaccination and substantially increased to 29.27 ± 80.64 mg/ml post-vaccination. The value of logIgA significantly increased (p = 0.003) from 0.28 ± 0.79 to 1.03 ± 0.54. The proportion of participants with equal to and greater than 3-fold and 4-fold shifts in pre- to post-vaccination antibody titer (IgA) were 55.4% and 48.3%, respectively. No adverse events or serious adverse events were recorded immediately within 30 min after the administration of each dose. The most common adverse events within 14 days after each visit were fever, unusual crying and irritability. Other adverse events occurred at a low rate, and no case of intussusception was noted.ConclusionsThe complete regimen of ROTAVAC® demonstrated an immunological response with clinically acceptable safety profile. Post-completion of this study, ROTAVAC® is now a WHO-prequalified vaccine and available in Vietnam.     

股骨近端髓内钉三维导航器的研制与测试

目的研发一种专用于防旋型股骨近端髓内钉置入时的三维导航器。方法选取颈干角为(135±5)°,并且股骨大转子顶点基本与股骨头中心等高的人体股骨骨骼的干标本32例,其中左侧16例,右侧16例。通过股骨头中心、平行于股骨干、垂直于股骨干与股骨颈所在的平面用钢锯将股骨标本的股骨头进行截骨;在股骨大粗隆顶端开口向股骨近端髓腔内插入PFNA主钉,主钉钉尾与股骨头中心点在同一高度上。在本课题所研发的股骨近端髓内钉三维导航器的导引下向股骨头颈部打入动力钉导引针,测量动力钉导引针在股骨头截骨面上的出针点与经股骨头中心点直线的垂直距离作为偏离值。结果利用本课题所研制的三维立体导航器在32例股骨骨骼的干标本上置入导引针,其中14例偏离值为0(占43.75%),最大偏离值为2mm,仅3例(占9.375%),平均误差只有0.69mm。结论本课题所研制的导航器结构简单,操作简便,定位精确,值得进一步在临床上研究应用。     

Why do A.T base pairs inhibit Z-DNA formation?

We have carried out free energy perturbation calculations on DNA double-stranded hexanucleotides. The sequence d(CGCGCG)2 has been "mutated" into d(CGTGCG).d(CGCACG) with the oligonucleotide in the A, B, and Z structural forms, both in vacuo and in aqueous solution. In addition, model free energy calculations have been carried out in which the electrostatic charges of the H-bonding groups of the bases in the major and minor grooves of the DNA are reduced to zero as a way of assessing the relative solvation effects of these groups in the different structural forms of DNA. Finally, energy component analyses have been carried out to assess the relative roles of different intranucleotide interactions on the B----Z equilibrium as a function of base sequence. In vacuo, the free energy for changing a G.C to an A.T base pair is largest in the Z conformation; in the A and B conformations, the free energy cost is approximately 2 kcal/mol lower (1 cal = 4.184 J). The results are similar when the simulations are run in explicit solvent: the change costs 3 kcal/mol more in the Z conformation than in the B form. These results are consistent with experimental data, where it is clear that A.T sequences are significantly more "Z-phobic" than G.C sequences. The calculations indicate that both intranucleotide and solvation interactions contribute to this Z-phobicity.     

HPLC-ELSD及紫外分光光度法测定三七中皂苷的含量

采用反相高效液相色谱蒸发激光散射检测器测定三七中人参皂苷Rg1的含量。色谱柱为CLC-ODS(6．0mm×150mm),流动相为乙腈-水(3070),蒸发激光散射检测器。定量方法简单,准确。回收率为100．50％,RSD为1．82％。并用紫外分光光度法测定了三七中总皂苷的含量,结果和HPLC法基本一致,说明该方法定量准确,回收率为101．50％,RSD为1．44％。结论认为两方法均可以控制三七的质量。