十一酸睾酮对人精浆蛋白的影响

本文采用SDS—PAGE法,测定7例健康育龄男子在肌肉注射十一酸睾酮(TU)前,用药后l、2、3个月及停药后精子计数恢复正常时的精浆蛋白浓度和组份变化,并结合血清测定激素水平及常规精液分析,以探讨TU对上述指标的影响及其相互关系。结果显示:用药早期精浆总蛋白浓度开始逐步降低,在停药后精子计数恢复正常时仍未达到正常水平。精浆总蛋白浓度的变化与精子活动率、前向运动率及LH呈正相关(r值分别为0.8975、0.7776、0.6406,P<0.01或0.05)。精浆蛋白组份也发生变化,其中51KD、37KD的蛋白条带变化最为明显,其变化除与精子活动率相关外(r=0.9094,P<0.01),其中51KD蛋白条带的变化还与精子前向运动率相关(r=0.7660,P<0.05)。上述结果提示TU可能在抑制生精之前即通过改变精浆蛋白而影响精子的功能,说明单用睾酮(T)的避孕机理是多因素的。     

综合治疗对脑梗塞相关危险因素的影响

目的　探讨综合治疗对脑梗塞复发的相关危险因素的影响。方法　随机选择85 例脑梗塞伴各类危险因素患者在综合治疗前后,对他们进行血压、空腹血糖、胆固醇、甘油三酯及血液流变学等8 项指标的测定。结果　经过1 ～3 年临床观察随访,有50 % 以上高血糖、高血脂、高粘滞血症患者检验指标趋于正常,94 .3 % 的高血压得到控制与稳定,经t 检验,血液流变学4 项P 值< 0 .05 ,差异有显著意义,高血压、空腹血糖、胆固醇、甘油三酯的P 值< 0 .01 ,差异有非常显著意义。结论　综合治疗对控制相关危险因素,预防脑梗塞复发有重要临床意义     

Combining qualitative with quantitative approaches to study contraceptive pill use

According to large-scale studies, oral contraceptive users become pregnant at rates that exceed ideal use failure rates. It is thought that a major cause is missed pills, but current research on consistent contraceptive pill taking is characterized by inadequate measures and a failure to investigate women's thinking about their own patterns of use. The purpose of this study was to gain some understanding about women's interpretations of consistency in their own pill taking through combining qualitative with quantitative data. The study was conducted in China, where contraception is free and widely available. Five urban and five rural oral contraceptive users were followed for up to three pill-taking cycles during 1996 for a total of 759 person-days. Consistency of pill taking was measured with electronic data obtained from a new blister package made by Anderson Clinical Technologies (Elmhurst, IL). Data from these devices were reviewed and interpreted by the study participants during in-depth private interviews. The users' reasons for missing pills included disruptions in their daily routines, their husband's absence, spotting, and trouble implementing the family planning program's instructions to take one pill per day for 22 days and start the next cycle on the fifth day of menses. One user gave these reasons for two cycles but denied missing numerous pills in her third cycle. Data from a series of four questionnaires showed that most demographic, psychosocial, and service system characteristics were not related to missed pills. However, results suggested that the daily routines of rural living may make consistent use more likely and that instructions for taking the pill may be associated with prolonged pill-free intervals and skipping pills during episodes of spotting. Three of the 10 women were at increased risk of pregnancy during the study period because of their pill-taking pattern. We concluded that the combination of qualitative with quantitative data enhances understanding of contraceptive use. Women themselves offer plausible reasons for their use behaviors. Listening to women could be useful in improving programs.     

应用脉冲多普勒估测右心室dp／dtmax方法的评价

目的通过动物实验及临床研究评价右心室射血期肺动脉脉冲多普勒频谱参数估测右心室收缩功能的可行性。方法6条健康犬及25例先心病患儿。1.在右心室正性肌力及改变前后负荷干预下,观察实验犬血流频谱最高速度（Vp）、加速时间（AT）、平均加速度（Am）及Vp2／AT等肺动脉射血期脉冲多普勒参数与右心室dp／dtmax的关系。2.测算先心病患儿上述各肺动脉射血期血流频谱参数并与心导管造影术中右室dp／dtmax测值比较。结果1．实验犬中仅Vp及Vp2／AT在右心室正性肌力及前后负荷干预下始终与右室dp／dtmax呈高度相关。2先心病患者肺动脉血流Vp、Am及Vp2／AT与右心室dp／dtmax成非常显著相关。结论右室Vp及Vp2／AT可用于右空心肌收缩力的估测。     

单纯性肥胖儿血清Leptin浓度测定及意义

目的了解单纯性肥胖儿童和青少年血清Leptin（LEP）浓度,其与体重指数（BMI）、血脂间的关系。方法用放免法检测30例肥胖儿童和30例健康儿童的血清LEP,并对其与BMI、血脂水平作相关分析。结果肥胖组与健康组比较血清LEP、BMI均显著增高（P＜0.01）,血脂六项指标中有三项（TG、apo-A、apo-B）肥胖组高于对照组（P＜0.01）肥胖组血清LEP浓度与BMI间相关性具显著意义（P＜0.05）,与血脂间（TG、apo-A）也呈现高度显著性相关（P＜0.005,P＜0.05）。＃哈肥胖儿童和青少年的血清LEP浓度增高,与BMI、与血脂部分指标间的正相关,表明脂肪组织分泌LEP与肥胖程度相关,血清LEP可能在血脂代谢活动中起作用。     

Biased distribution of msp1 and msp2 allelic variants in Plasmodium falciparum populations in Thailand

Plasmodium falciparum isolates were obtained from Thai patients attending a malaria clinic on the Thai-Kampuchean border over 4 cross-sectional surveys carried out at 3-monthly intervals. The genetic structure of the parasite populations was determined by nested polymerase chain reaction (PCR) amplification of polymorphic regions of 3 P. falciparum antigen genes: msp1, msp2 and glurp. Although a high degree of diversity characterized these isolates, the overall population structure of the parasites associated with patent malaria infections was observed to remain relatively stable over time. The highest degree of polymorphism was observed with msp2, and the mean number of lines per infection (multiplicity of infection) calculated with this marker was higher than that obtained using msp1 or glurp alone, or combined. Infections with > or = 2 parasite lines were seen in 76% of the samples, and were proportionally more numerous at the start and end of the rainy season. Two interesting exceptions to the random distribution were observed and involved 2 allelic variants which in one case were found dissociated (msp1 MAD20-family) and in the other were associated (msp2 FC27-family). The epidemiological significance of these types of data is discussed.     

Plasma apolipoprotein B-48, hepatic apolipoprotein B mRNA editing and apolipoprotein B mRNA editing catalytic subunit-1 mRNA levels are altered in zinc-deficient rats.

Apolipoprotein B (apoB) exists as two major isoforms and serves as an obligatory component of lipid-rich plasma lipoprotein particles. Apolipoprotein B mRNA editing is a zinc-dependent, site-specific cytidine deamination that determines whether the apoB-100 or apoB-48 isoform is synthesized. The objective of this work was to examine whether dietary zinc levels affect apoB mRNA editing in vivo. Adult male Sprague-Dawley rats were randomly assigned to zinc-deficient (ZD, <0.5 mg Zn/kg diet), zinc-adequate (ZA, 30 mg Zn/kg diet) or zinc-replenished (ZDA, ZD rats fed the ZA diet for last 2 d) dietary groups for 18 d. The ratio of plasma apolipoprotein B-48 (apoB-48) to total apoB was significantly lower in zinc-deficient compared with zinc-adequate rats. Primer extension analysis indicated a modest but significant reduction in hepatic apoB mRNA editing in ZD rats compared with that of the ZA group. In ZDA rats, hepatic apoB mRNA editing and the percentage of plasma apoB-48 to total apoB were not different from ZA rats. The mRNA abundance of hepatic apobec-1 (apoB mRNA editing catalytic subunit 1) was significantly lower in ZD and ZDA rats than in ZA rats. In summary, the plasma ratio of apoB-48 to total apoB protein as well as hepatic apoB mRNA editing and hepatic apobec-1 mRNA levels were reduced in rats consuming a zinc-deficient diet. These data suggest that one or more components of apoB metabolism may be influenced by dietary zinc status.     

Role of the D2 dopamine receptor in molecular adaptation to chronic hypoxia in PC12 cells

We have previously shown that pheochromocytoma (PC12) cells rapidly depolarize and undergo Ca2+ influx through voltage-dependent Ca2+ channels in response to moderate hypoxia and that intracellular free Ca2+ is modulated by activation of dopamine D2 receptors in this cell type. The present study shows that D2 (quinpirole-mediated) inhibition of a voltage-dependent Ca2+ current (ICa) in PC12 cells is dramatically attenuated after chronic exposure to moderate hypoxia (24 h at 10% O2). Pretreatment of cells with pertussis toxin abolished D2-mediated inhibition of ICa. The D2-induced inhibition of ICa did not depend on protein kinase A (PKA), as it persisted both in the presence of a specific PKA inhibitor (PKI) and in PKA-deficient PC12 cells. Prolonged exposure to hypoxia (24 h) significantly reduced the level of Gi/o alpha immunoreactivity, but did not alter G beta levels. Furthermore, dialysis of recombinant G(o) alpha protein through the patch pipette restored the inhibitory effect of quinpirole in cells chronically exposed to hypoxia. We conclude that the attenuation of the D2-mediated inhibition of ICa by chronic hypoxia is caused by impaired receptor-G protein coupling, due to reduced levels of G(o) alpha protein. This attenuated feedback modulation of ICa by dopamine may allow for a more sustained Ca2+ influx and enhanced cellular excitation during prolonged hypoxia.     

肝海绵状血管瘤的螺旋CT表现特征

目的：分析肝海绵状血管瘤的螺旋ＣＴ表现特点,探讨应用螺旋双期或三期增强扫描鉴别肝内实性占位灶的价值。方法：对４８ 例患者ＣＴ平扫发现肝内占位病灶后采用螺旋ＣＴ增强扫描。造影剂单相注射,每秒３～３．５ ｍ ｌ,每例５０～８０ ｍ ｌ。第一相全肝螺旋增强扫描在造影剂注入后２０～２５ ｓ开始,第二相６０～７０ ｓ,延迟５～１５ｍ ｉｎ 对病灶所在的层面进行扫描。结果：５８ 个病灶平扫均为境界清楚的低密度区,增强后４３ 例（８９．５８％ ）于动脉期出现病灶边缘部致密的结节状或斑块状强化,门静脉期扫描增强区域扩大或整个结节增强。延迟扫描病灶全部强化或绝大部分强化,密度与肝实质相等或稍高。３ 例（６．２６％ ）动脉期表现为致密强化结节影（直径＜ ２ｃｍ ）, 门静脉期结节密度变淡,延迟扫描病变与肝脏等密度。２ 例（４．１６％ ）动脉期未见病灶强化,门静脉期病灶稍小,延迟扫描病变呈等密度灶。结论：肝海绵状血管瘤的特征表现是增强早期病灶边缘区的结节状致密强化,与肝癌的鉴别之处在于延迟相病灶表现为相等或稍高密度