Issues in human immunodeficiency virus (HIV) screening programs.

Unlike test sensitivity and specificity, the false positive and negative predictive values (probabilities of mislabeling an individual being tested) depend heavily on the prevalence of the infection of the human immunodeficiency virus (HIV) as well as the quality of the kit. A consequence of this dependence is that the false positive predictive value can reach a high magnitude such as 0.9; that is, 90% of the positive tests are false. This raises many important issues pertaining to the current practice of HIV screening such as to how to control these misclassification errors, how to interpret test results, and how to estimate prevalence using test results. These issues are examined in detail here by considering the factors that dictate the quality of a screening program. Some real data examples are used to illustrate the importance of this consideration in designing programs to achieve the desired goals. The rationale behind the common two-step sequential protocol in HIV screening is examined to point out its limitations under practical situations. Finally, the use of entropy in evaluating the informativeness of a screening program is discussed.     

Predisposing factors of restless legs syndrome in pregnancy.

The occurrence of restless legs syndrome in pregnancy is well known. However, the mechanism of this association is unclear. In this study, we aimed to identify the factors that predispose women to have restless legs syndrome during pregnancy. A total of 146 pregnant women were included in the study. Patients were asked questions regarding demographic characteristics, complications of pregnancy, medical therapy (vitamin and iron intake), sleep disorders, muscle cramps, and excessive daytime sleepiness. Electroneurography, routine blood biochemistry tests, complete blood count, and thyroid function tests were performed and vitamin B12, folic acid, serum iron, iron-binding capacity, ferritin, iron saturation, prolactin, estradiol, and progesterone were measured. Of the participants, 38 were diagnosed as having restless legs syndrome. In women with restless legs syndrome, additional medical problems, night cramps, and excessive daytime sleepiness were more frequent. In women without restless legs syndrome, serum hemoglobin levels were significantly higher and the use of supplemental iron or vitamins was greater. Among the women with restless legs syndrome, progesterone levels were slightly higher but this difference was not statistically significant. In summary, in this study, lower hemoglobin levels and supplementation deficits of iron and vitamins were found be the risk factors for restless legs syndrome in pregnancy.     

疟原虫抗原B表位NKNDD和NANP串联重复片段与脊灰病毒全长cDNA嵌合体的构建

人工合成含有恶性疟原虫抗原B表位NKND的单拷贝抗原基因片段NKNDD和恶性疟原虫环子抱子蛋白CSP的重复性抗原B表位NANP的2拷贝基因片段，将NKNDD和（NANP）。分别进行自串联后克隆到中介载体PSKMM，得到一系列不同拷贝数的串联多拷贝克隆。从（NKNDD）n／PSKMM和（NANP）n／pSKMM的各拷贝克隆中挑选3、4、5、8拷贝的（NKNDD）n／PSKMM和4、6拷贝的（NANP）n／pSKMM，将（NKNDD）n和（NANP）n从中介载体转移到表达型载体pSV202H＋，得到3、4、5、8拷贝的（NKNDD）n和4、6拷贝的（NANP）n插入脊髓灰质炎病毒Ⅰ型Mahoney株全长cDNA的N－AgⅠ区域所构成的嵌合体。实验中由于引入了半定量杂交技术，使得单位DNA片段的系列串联和克隆过程明显简化。     

绍兴市麻疹发病时间聚集性分析

目的 探讨绍兴市麻疹发病的季节性及其变动趋势。方法 采用集中度和图形分布法对该市1955－1964年，1965－1983年，1984－2001年3个阶段的麻疹发病资料进行时间聚集性分析。结果 两种分析方法获一致的统计分析结果，即麻疹发病具有一定的季节性。用圆形分布法求得3个阶段发病高峰时点分别为3月12日，3月24日及4月25日，高峰时期分别为12月29日－5月23日（148天），1月7日－6月12日（155天）和2月27日－6月26日（120天）。3个阶段高峰时点经Watson与Williams检验差异有显著性。结论 绍兴市麻疹发病高峰点后移，自1965年使用麻疹疫苗后，高峰时期缩短，发病季节性增强。     

血浆弹性蛋白酶的微量测定和临床应用

目的　拟建立一种血浆弹性蛋白酶的快捷、微量测定方法。方法　以琥珀酰甘氨酰对硝基苯胺 (succinyl-L -trianalinyl-p -nitroanilide ,SLAPN)作为弹性蛋白酶的作用底物 ,根据单位时间内 4-硝基苯胺释放量 (A450nm)的变化 ,反应弹性蛋白酶的活性。结果　线性范围为 0～ 5 0 0 μg/L,批内和批间误差分别为 5 .0 2 %和 8.3 2 % ,血浆用量仅为 2 0～ 40 μl。正常健康人 (n =12 )血浆弹性蛋白酶含量 (3 7.5 0± 15 .5 6)μg/L。肠瘘合并感染患者 (n =6)为 (4 8.40± 2 7.82 )μg/L,明显高于正常人 (P <0 .0 1)。猪急性出血坏死性胰腺炎 (5 %牛磺胆酸钠 + 80 0 0～ 10 0 0 0u/ml胰蛋白酶 )诱导12h后为 (2 3 9.0 6± 180 .2 4) μg/L明显高于诱导前水平〔(3 6.15± 9.40 ) μg/L,P <0 .0 1〕。结论　该方法操作简便、快捷、灵敏度高、特异性好 ,易推广普及     

Acting via A_2 receptors，adenosine inhibits H_2O_2 production and elastase releaseon FMLP一stimulated

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学习记忆能力下降大鼠神经细胞增殖的研究

目的　观察学习记忆能力减退老年大鼠海马齿状回神经细胞的增殖。方法　Morris水迷宫筛选出学习记忆能力减退大鼠 (痴呆组 )与正常大鼠 (对照组 )。BrdU标记海马齿状回增殖细胞。TUNEL法标记DNA片段原位检测凋亡细胞。计数海马颗粒细胞层与海马门的BrdU阳性细胞与凋亡细胞数。结果　痴呆组与对照组大鼠相比 ,海马颗粒细胞层BrdU阳性细胞显著增加 (P <0 0 1) ,而凋亡细胞数无显著差异 (P >0 0 5 )。海马门BrdU阳性细胞数及凋亡细胞数均无显著差异 (P >0 0 5 )。结论　学习记忆能力减退的老年大鼠海马齿状回神经细胞增殖能力减低。     

合欢皮中新皂甙的结构鉴定

从合欢皮(Albizziae cortex)的95%乙醇提取物的正丁醇萃取部分中分离得到3个新的三萜皂甙,用化学方法及¹H-和¹³C-NMR,DEPT,COSY,TOCSY,HMQC-COSY,HMQC-TOCSY,HMBC,NOESY等波谱方法鉴定其结构为:I(1个三萜,9个糖,2个单萜),命名为合欢皂甙(julibroside)J₁;II(1个三萜,8个糖,2个单萜),命名为合欢皂甙J_{2;II(1个三萜,9个糖,2个单萜),命名为合欢皂甙J3。}     

尖锐湿疣患者外周血淋巴细胞凋亡调控蛋白的表达和血清中白细胞介素2水平的研究

为研究尖锐湿疣（CA）患者外周血淋巴细胞（PBLC）凋亡调控蛋白表达水平和血清中白介素2（IL－2）水平在CA免疫发病机制中的作用。采用流式细胞仪及间接免疫荧光素标记法和ELISA法，检测了60例不同病程CA患者PBLC凋亡调控蛋白Fas/Fas-L的表达水平和血清中IL－2水平。发现CA短病程组PBLC的Fas、Fas-L表达水平均明显高于健康对照组（P＜0.05)，而CA长病程组PBLC的Fas、Fas-L表达水平明显高于CA短病程组（P＜0.05)和健康对照组（P＜0.01)，短、长病程组CA患者血清IL－2的水平明显低于健康对照组（P＜0.01)，CA患者PBLC Fas/Fas-L表达水平与血清中IL－2的水平呈负相关（P＜0.01)。结果表明：CA患者PBLC有凋亡异常，并且与血清中IL－2的水平呈负相关，患者PBLC凋亡异常在CA的病程中可能起重要作用。