Plasma leptin level and its relationship with body composition in hemodialysis patients

Leptin is a newly found hormone secreted by adipocytes that regulates food intake, thermogenesis, and body fat. We measured plasma leptin levels in 103 patients with chronic renal failure treated by hemodialysis and 167 age- and gender-matched healthy control subjects to examine the impact of renal failure on plasma leptin levels and the influence of leptin on body composition measured by dual-energy X-ray absorptiometry. Hemodialysis patients showed a significant decrease in both body fat mass and lean body mass compared with those of the control subjects. Plasma leptin was significantly elevated in the hemodialysis group over the controls. In both groups, leptin was higher in female than male subjects, and it correlated positively with percent body fat. The subjects were divided into six categories according to percent body fat, and plasma leptin levels were compared between the two groups in the same category. Leptin of hemodialysis patients was significantly higher than that of the control subjects in the percent body fat categories of 30 or greater, whereas there was no statistically significant difference in leptin concentrations in the lower percent body fat categories. This was also true in the comparison in each gender, and leptin levels in female subjects showed a more remarkable difference between the hemodialysis and control groups in obese categories. Multiple regression analysis in all subjects indicated that plasma leptin levels were independently affected by percent body fat, plasma insulin concentration, gender, and renal failure. The positive impact of renal failure on leptin remained significant in the subjects with percent body fat of 30 or greater in the multiple regression model, whereas it was no longer significant in the remaining lean subjects. In multiple regression analysis of factors affecting fat mass index and lean mass index, leptin level was selectively associated with fat mass index, but not with lean mass index, regardless of percent body fat ranges. These results indicate that renal failure is an important factor affecting plasma leptin levels, especially in obese female subjects, and that hyperleptinemia was closely related to fat mass but not to lean body mass in hemodialysis patients.     

家兔静注水杨醛-N'-(2-呋喃硫羰基)腙铜配合物的药物动力学

目的：研究水杨醛－Ｎ′－（２－呋喃硫羰基）腙铜配合物（ＣＳＦＣ）在兔体内的药物动力学。方法：１０只家兔静脉注射ＣＳＦＣ５ｍｇ·ｋｇ－１，用反相ＨＰＬＣ法测定血清药物浓度。结果：ＣＳＦＣ的血药浓度－时间曲线符合二室开放模型，主要药动学参数为：Ｔ１２α＝３．４±１．７ｍｉｎ，Ｔ１２β＝６５．５±１４．６ｍｉｎ，Ｋ１２＝０．１１８３±０．０６６９ｍｉｎ－１，Ｋ２１＝０．０２２８±０．００６５ｍｉｎ－１，Ｋ１０＝０．１２０２±０．０４０７ｍｉｎ－１，Ｖ０＝０．３０５±０．１８４Ｌ·ｋｇ－１，ＣＬ＝１．８９６±０．４７０Ｌ·ｋｇ－１·ｈ－１，ＡＵＣ＝１７０．１±５７．０ｍｇ·ｍｉｎ－１·Ｌ－１。结论：ＣＳＦＣ在兔体内分布迅速而广泛，消除也较快。家兔静注５ｍｇ·ｋｇ－１，可维持抗结核杆菌有效血浓度６ｈ。     

海脉冲营养素对小鼠造血功能的影响

通过与复方阿胶浆，施普端螺旋藻胶囊抗贫血功效的比较，研究了海脉冲营养素对小鼠造血功能的影响。结果表明，小鼠口服ＨＭＣ５００ｍｇ／（ｋｇ．ｄ），对失血性贫血小鼠有提高，ＲＢＣ的作用，对苯肼引起的溶血性贫血小鼠有升高Ｈｂ，ＲＢＣ，ＷＢＣ的作用，能促进由环磷酰胺所致骨髓抑制小鼠的骨髓有核细胞的增殖，增加脾脏重量，升高外周血中网织红细胞和ＷＢＣ数量。     

小鼠不完全性脑缺血、再灌注时脑膜血流量的变化及尼莫地平的作用

目的：观察双侧颈总动脉阻断后脑血流的变化。方法：结扎双侧颈总动脉观察小鼠不完全性脑缺血及其再灌注时脑膜血流量的变化。结果：结扎颈总动脉后小鼠脑膜血流量在几秒钟内骤然下降，血流量较结扎前降低约８５．９％±６．４５％。同时血管中红细胞运动近停滞状态，血管再通时脑血流处于低灌注状态，血流量下降３４．４７％±１１．６９％，此时脑缺血再灌后脑组织实际上处于一种慢性缺血状态。再灌注１０ｄ后，小鼠脑海马ＣＡ１区神经细胞数明显减少。尼莫地平可以解除再灌注时的脑血流低灌状态。并防止由此所引起的脑海马ＣＡ１区神经细胞的缺失。结论：缺血后及时给予尼莫地平具有积极的治疗意义。     

心肌造影超声心动图评估心肌缺血程度的实验研究

本实验制作不同程度心肌缺血的动物模型，以声处理５％人血白蛋白为超声造影剂进行心肌灌注造影，探讨ＭＣＥ时间－强度曲线各指标与心肌缺血程度间的关系。结果表明：心肌显影的峰值强度和曲线下面积均与缺血程度呈显著负相关（相关系数分别为ｒ＝－０．９８，Ｐ值＜０．００５；ｒ＝－０．９４，Ｐ值＜０．０５），且能区分轻度、中度和重度三种程度的心肌缺血；而三项时间指标与心肌缺血程度间未发现显著性差异。本实验的初步结果表明，ＭＣＥ是一项活体评估局部心肌血流灌注的有效方法。     

腰椎管上下缘矢径的测量及腰椎管狭窄的诊断

用２‰游标卡尺对１１４具Ｌ１～Ｌ５段椎骨标本进行测量，包括椎孔上缘矢径及下缘矢径的距离和相互关系。结果：腰椎孔下缘矢径明显大于上缘矢径（Ｐ＜０．０１），腰椎孔下缘矢径明显大于腰椎孔中矢径。为腰椎管狭窄的临床诊断提供解剖学基础。     

从包涵体中纯化重组人幽门螺杆菌热休克蛋白A亚单位

目的：建立一种有效从包涵体中纯化重组人幽门螺杆菌热休克蛋白A亚单位HspA的方法。方法：重组基因工程大肠杆菌发酵后，表达的Hp r HspA包涵体经洗涤，变性，复性，采用Q Sepharose High Performance阴离子交换层析和Superdex75凝胶过滤层析分离纯化，使用SDS－PAGE和HPLC检测纯度，选用ELISA和动物实验对纯化蛋白的免疫学活性和生物学活性进行鉴定。结果：Hp的HspA包涵经洗涤和溶解后，Hp的HspA的纯度＞60％，包涵体溶解液经阴离子交换层析和凝胶过滤层析后纯度超过95％，Hp的HspA纯品经检测具有良好的免疫学活性和生物学活性。结论：本研究建立的分离纯化方法可从包涵体中获得高纯度的重组HspA蛋白，为进一步的动物实验研究奠定了基础。     

Impairment of acid-neutralizing capacity and lesion formation in the rat duodenum during hemorrhagic shock: comparative study with indomethacin

The effects of hemorrhagic shock (HE) on duodenal pH, acid-neutralizing capacity and mucosal tolerance to acid were investigated in anesthetized rats, and they were compared with those of indomethacin. HE was performed by bleeding from the carotid artery to reduce arterial blood pressure to about 55 mmHg (3 ml of bleeding per 200 g of body weight), and indomethacin was given s.c. in a dose of 5 mg/kg. Duodenal pH was determined in the outflow from the proximal duodenum (1.7 cm) which was perfused with 10(-4) M HCl, and acid-neutralizing capacity was measured by back-titration of the perfusate to pH 4.0 with 10 mM HCl. Under these conditions, duodenal pH was kept at around 6.0 as the result of neutralization in the loop (approximately 8 microEq/hr). Both HE and indomethacin significantly decreased the pH and acid-neutralizing capacity. Administration of 16,16-dimethyl prostaglandin E2 (16-dmPGE2: 30 micrograms/kg, s.c.) significantly increased both pH and acid-neutralizing capacity in normal and indomethacin-treated rats, but failed to affect these parameters in rats under HE conditions. When the duodenal loop was perfused with 50 mM HCl for 1.5 hr, both HE and indomethacin induced extensive damage in the mucosa. Pretreatment with 16-dmPGE2 significantly reduced the formation of duodenal lesions induced by indomethacin but not by HE. These results suggest that HE as well as indomethacin impaired duodenal acid-neutralizing capacity to reduce the tolerance to acid of the mucosa. The deleterious effects of HE on the mucosa may be mainly due to a decreased mucosal blood flow, but not due to a deficiency of endogenous prostaglandins.     

永存左上腔静脉在心脏直视手术中的处理

自1981年8月至1996年10月施行心脏直视手术1800例，发现永存左上腔静脉（PLSVC）11例，其中引入左心房1例。全部并发于其它心内畸形，且无特异体征。认为本中仔细探查是对PLSVC诊断的重要环节。本文对注意事项以及对不同类型的PLSVC引流入左房的外科处理方法进行了阐述。