梯度胶电泳法测定冠心病患者血浆小密低密度脂蛋白

目的 建立实用的小密低密度脂蛋白(sdLDL)测定方法, 观察冠心病患者血浆中sdLDL和脂类成分的变化及相互关系。方法 采用2%～16%非变性聚丙烯酰胺梯度胶电泳和凝胶成象分析系统, 测定了105名冠心病患者和90名健康对照者血浆sdLDL、 血脂。结果 sdLDL＞50%的检出率, 冠心病组为38.1%, 对照组为11.1%(P＜0.01);sdLDL增多患者的甘油三酯水平(2.43±1.22) mmol/L明显高于sdLDL正常者(1.46±0.64) mmol/L, P＜0.01。结论 sdLDL与冠心病发生发展有关, 且与甘油三酯关系密切;sdLDL测定可作为预测冠心病危险性的指标之一。     

顺铂引起卵巢癌细胞周期变化及凋亡的观察

目的 :了解顺铂 (DDP)引起卵巢癌细胞COC1、COC1/DDP细胞周期变化及凋亡规律。方法 :用光镜、电镜及流式细胞术等方法观察细胞凋亡规律及进行细胞周期分析。结果 :DDP引起COC1、COC1/DDP细胞周期变化主要表现为S期阻滞 ,P <0 .0 1;细胞死亡方式主要是凋亡 ,凋亡细胞发生在S期 ,P <0 .0 1;COC1、COC1/DDP细胞凋亡率不同 ,COC1凋亡率高 ,两组相比差异有显著性 (P <0 .0 1)。结论 :DDP引起COC1、COC1/DDP细胞S期阻滞、S期细胞凋亡 ,细胞凋亡与获得性耐药有关     

幽门螺杆菌分离培养技术的改进

探讨自制的改良布氏活性炭巧克力培养基,置厌氧罐蜡烛培养环境分离临床粘膜标本幽门螺杆菌(Hp)的检出率.结果表明66例粘膜标本中分离出Hp54株(81.8%),44株Hp滤液有24株(54.5%)具有细胞毒活性,其中26例消化性溃疡患者有18例(69.2%),18例慢性胃炎患者有6例(33.3%)为Hp(Toxin+)感染.结果提示通过对Hp生物学性状和毒素的检测结果证实,该法可用于临床粘膜标本Hp的常规分离培养.     

耐甲氧西林葡萄球菌HVR基因分型及其与耐药性的关系

目的 为获得成都地区耐甲氧西林葡萄球菌的HVR－PCR基因型,比较HVR基因型与耐药谱的关系,从而指导临床合理选用抗生素,并初步探讨其在分子流行病学分析中的作用。方法 从成都地区四家三甲医院收集到临床分离的葡萄球菌114株。其中86株MRSA、10株MRSE（Mc‘S.epidemidis)、5株MSSE（Mc‘S.epidemidis)、8株MRSH（Mc‘S.haemolyticus)和5株MSSH（Mc‘S.haemolyticus)。用琼脂平皿二倍稀释法测定其MIC值,优良的碱裂解法提取DNA,应用PCR技术,扩增mec基因高变区（HVR区）,聚丙烯酰胺凝胶垂直板和琼脂糖凝胶电泳分型。结果 根据PCR产物片段大小,MRSA、MRSE和MRSH分别被分为4种、3种和2种基因型,其中有9株MRSE的PCR扩增产物片段大小与MRSA相同。MRSA主要为A、D型,分别占52．32％和39．53％;B、C型最为耐药,而D型对多种药物敏感。MRSE的Ⅰ型为高度多重耐药株,而Ⅲ型对多种抗生素敏感。MRSH的a型比b型耐药。结论 HVR－PCR法对于由MRSA引起的院内感染的流行病学调查是一种快速、简单、可靠的分型法,且有利于抗菌药物的选用。这种方法能够部分比较MRSA菌株和耐甲氧西林的凝固酶阴性葡萄球菌（Mc‘CNSt)的mec决定因子,从而探讨其起源。     

Response rates in metastatic neuroendocrine tumors receiving peptide receptor radionuclide therapy and implications for future treatment strategies

BackgroundPeptide receptor radionuclide therapy is a targeted therapy used to treat unresectable somatostatin receptor-positive neuroendocrine tumors. The objective of this study was to evaluate response rates among neuroendocrine tumors of different primaries and identify factors relevant to future treatment strategies.MethodsWe retrospectively reviewed patients who received peptide receptor radionuclide therapy for neuroendocrine tumors from 2018 to 2019 at our institution. Patients were assessed with computed tomography/magnetic resonance imaging and ⁶⁸Ga-DOTATATE-positron emission tomography before and after 2 or 4 cycles of peptide receptor radionuclide therapy. Tumor response was evaluated by RECIST 1.1. Statistics included multinomial logistic regression models and Fisher exact test.ResultsTwenty-seven patients underwent 92 cycles of peptide receptor radionuclide therapy: pancreas (n = 11), small bowel (n = 7), and other (n = 9) neuroendocrine tumors. Overall, 30% (8 of 27) had partial response, 59% (16 of 27) stable disease, and 11% (3 of 27) progressed. Pancreatic neuroendocrine tumors responded differently from small bowel neuroendocrine tumors regardless of cycle number (P = .01). The majority of pancreatic neuroendocrine tumors (6 of 11) had partial response to peptide receptor radionuclide therapy, while all small bowel neuroendocrine tumors had stable disease. Pancreatic neuroendocrine tumors stable after 2 cycles were more likely to respond to additional cycles versus other neuroendocrine tumors (probability: 60% vs 11%).ConclusionPatients with unresectable advanced or metastatic pancreatic neuroendocrine tumors may benefit from a full course of peptide receptor radionuclide therapy, whereas other neuroendocrine tumors appear less likely to respond. Large prospective studies are needed to confirm these findings.     

Universally conserved and yeast-specific U1 snRNA sequences are important but not essential for U1 snRNP function

To study the contribution of the large, 568-nucleotide yeast (Saccharomyces cerevisiae) U1 snRNA to pre-mRNA splicing, we generated mutations in two regions of the molecule and introduced each mutant gene back into yeast as the sole copy of the U1 snRNA gene. We mutagenized the "A loop," a subregion highly conserved in primary sequence in all U1 snRNA molecules analyzed to date. We also mutagenized a portion of the yeast core subdomain, a region conserved in primary and secondary structure among several yeast species but absent from the much smaller metazoan U1 molecule. Surprisingly, mutations in these two regions had little or no effect on growth rate, yet several of them affected an inefficiently spliced reporter gene construct. In addition, combinations of mutants in both regions gave rise to reduced growth rates. Using the latter assay, we confirmed some of the proposed secondary structure of the yeast core domain. The experiments indicate that both regions contribute to U1 snRNP activity but that mutations in a single region do not have a substantial effect on growth rate because U1 snRNP activity is not rate-limiting for growth.     

绝经后骨质疏松大鼠模型的综合评价

利用双能X线骨密度仪、扫描电镜和骨生物力学试验综合评价大鼠去卵巢后的骨骼状况。结果显示：①大鼠卵巢切除后,活体、离体腰椎以及股骨（除R3区）、胫骨近端干骺端（R1区）的离体骨密度显著下降（P＜0.01),离体L5和L6的骨丢失率最大,达13%;②骨小梁减少、变细,连接中断,骨小梁表面有吸收陷窝;③腰椎压缩强度和股骨力学性均下降,前者更明显,腰椎最大压缩力下降率达33.32%。提示：①类似于绝经后妇女,6月龄大鼠在卵巢切除4个月后骨量和骨质量均下降,特别在富含松质骨的部位,如腰椎、股骨远端等;②利用绝经后骨质疏松大鼠模型评价骨质疏松新药的有效性,应包括该新药对骨量、骨结构和骨强度的作用。