海风藤及其代用品药理作用的比较研究

选择经典的实验指标，对海风藤及其３种代用品山Ｊｕ，石楠藤有毛Ｊｕ的药理作用进行了比较研究，结果表明海风藤，山Ｊｕ和毛Ｊｕ在抗炎，镇痛和抗血小板聚集方面均有效，其中海风藤作用最强，其次为山Ｊｕ，毛Ｊｕ石楠藤没有明显的抗炎作用，其抗血小板聚集及止痛作用稍强于毛Ｊｕ。     

The isolated spinal cord-skin preparation of the newborn rat and effects of some algogenic and analgesic substances

We have developed an isolated spinal cord-skin preparation of the newborn rat. The spinal cord together with a piece of skin connected to the cord by the saphenous nerve was isolated from 1- to 4-day-old rats and separately superfused with artificial cerebrospinal fluid in two neighbouring chambers. Potentials were recorded extracellularly from the third lumbar ventral root. Application of capsaicin (0.5-2 μM) or KCl (60–350 mM) with brief pressure pulses to the perfusion bath of the skin evoked a depolarizing response of 20- to 40-s duration in the ventral root. The response was depressed by [Met⁵]enkcphalin (0.03–3 μM). morphine (0.1–2 μM) and a tachykinin antagonist, [D-Arg¹,D-Trp^7,9,Leu¹¹] substance P (spantide), 1–10 μM), applied to the spinal cord by superfusion, whereas the response was augmented by centrally administered calcitonin gene-related peptide (0.1–0.2 μM) or bicuculline (0.5–1 μM).     

Integration of new regulatory strategies into the network of an endocrine control system: limitation of androgen secretion by rat testis is achieved by substrate-dependent modulation of P450XVII enzyme concentration and catalytic efficiency.

In addition to the well-known control circuits involved in the regulation and adaptation of testicular androgen biosynthesis, it is proposed that two new control strategies are involved in the maintenance of steady-state testosterone secretion rates by testicular Leydig cells. Cytochrome P450XVII (steroid-17 alpha-monooxygenase/steroid-17,20-lyase), one key enzyme in steroid hormone biosynthesis, responds to external human choriogonadotropin stimulation with an oxygen-dependent and substrate flux-dependent inactivation and decomposition, and increased substrate availability decreases the efficiency of androgen formation in favour of abortive intermediate leakage. These results are discussed as a paradigm of substrate-dependent modulation of cytochrome P450 activities.     

细胞色素P450调节剂对DNA加合物形成的影响

人羊膜上皮细胞ＦＬ系分别接触ａ－萘黄酮（０．６ｍｍｏｌ·Ｌ￣（－１））β－萘黄酮（２０ｐｍｏｌ·Ｌ￣（－１））２４ｈ后，再用苯并（ａ）芘［Ｂ（ａ）Ｐ，１０ｕｍｏｌ·Ｌ￣（－１）］处理２４ｈ，用３２Ｐ后标记技术测定以Ｂ（ａ）－ＤＮＡ加合物。结果发现，阳性对照组，ａ－萘黄酮预处理组及β－萘黄酮预处理组加合物的量分别为（加合物个数／１０’个核苷酸）：４．７±０．２（１００％），１．８±０．９（３８．３％），１６．０±２．２（３４０．１％）．该实验结果直接显示了纳胞色素Ｐ４５０调节剂对肿瘤发生影响的作用水平。亦为药物对致癌物代谢影响的研究提供了一种方法．     

Effects of systemic clonidine on auditory event-related potentials in squirrel monkeys

Event-related potential (ERP), electroencephalographic (BEG), and behavioral data were collected from squirrel monkeys (Saimiri sciureus) in a 90−10 auditory oddball paradigm. Background or target tones were presented once every 2 s, and responses to the targets were rewarded. ERPs were recorded from epidural electrodes following systemic administration of clonidine (0.1 mg/kg) or a saline placebo. EEG power spectra and behavioral performance were assessed simultaneously as indices of behavioral state. Clonidine significantly decreased the area and increased the latency of a P300-like potential. The amplitudes and areas of the earlier P1, N1, and P2 components and a later slow wave-like potential were not reduced, nor were their latencies altered. Clonidine produced increased EEG power in the alpha range (7.5–12 Hz) and decreased power in the upper beta range (20–40 Hz) but did not affect performance in the oddball task. Because two major effects of clonidine are to substantially reduce activity in the noradrenergic nucleus locus coeruleus (LC) and to reduce norepinephrine (NE) release from axons, the present results support the hypothesis that the LC and its efferent projection system are important in modulating the activity of P300-like potentials.     

Altered enzyme activities of xenobiotic biotransformation in kidneys after subchronic administration of 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX) to rats

Activities of the xenobiotic metabolizing enzymes were measured in the liver, kidney, duodenum and lung microsomes and cytosol fractions of Wistar rats after subchronic administration of 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX), a potent bacterial mutagen in chlorinated drinking water. MX was administered by gavage at the dose level of 30 mg/kg for 18 weeks (low dose), or at the dose level which was raised gradually from 45 mg/kg for 7 weeks via 60 mg/kg for 2 weeks to a clearly toxic dose of 75 mg/kg for 5 weeks (high dose). Microsomal and cytosolic preparations were made and the activities of 7-ethoxyresorufin-O-deethylase (EROD), pentoxyresorufin-O-dealkylase (PROD), NADPH-cytochrome-c-reductase, UDP-glucuronosyltransferase (UDPGT) and glutathione-S-transferase (GST) were measured. Kidneys were affected most. A dose-dependent decrease was observed in EROD (90% in males, 80% in females at the high dose) and in PROD (58% in females, at the high dose) in kidneys. An increase was, however, detected in kidney NADPH-cytochrome-c-reductase (66% in females at high dose), UDPGT (89% in males and 97% in females at high dose) and GST activities (56% in males and 50% in females at high dose). MX caused only a few changes in the enzyme activities of the liver. The EROD activity was decreased 25% to 37%, both in the livers of males and females, but the total content of P450s was not altered. Hepatic GST activity was elevated in females in a dose-dependent manner (31% and 44%). GST activity was elevated in duodenum in females (59%) at the high dose. There were no marked changes in the enzyme activities in the lungs. MX was a weak inhibitor of EROD activity both in the liver and kidney microsomes in vitro, decreasing the EROD activity by 53% and 43%, respectively at the concentration of 0.9 mM. The results indicate that MX decreases the activity of phase I metabolism enzymes, but induces phase II conjugation enzyme activities, particularly in kidneys in vivo. It is possible that these changes contribute to metabolism of MX in kidneys and renders them susceptible to MX in the course of repeated exposure.     

P波时限、P波离散度对特发性心房颤动的预测价值初探

Objective:To assess the sensitivity and the specifity of predicting idiopathic AF with P wave dura-tion and P wave dispersion. Methods: The maximum P wave duration and P wave dispersion in 36 patients with idio-pathic AF were measured and compared with those of sex-and age-matched healthy subjects. Results:The maxi-mum P wave duration and P wave dispersion were higher in patients with idiopathic Af than in control group. Themaximum P wave duration >110ms or P wave dispersion >40ms was used to differentiate patients from healthy     

北京、广州、上海城市居民营养知识、态度、行为的调查

对北京、广州和上海三大城市随机抽取的９６５名年龄在２０～５０岁的城市居民进行有关营养知识、态度和行为（Ｋ－Ａ－Ｐ）的调查。结果显示，三地区调查对象的营养知识水平不高。营养知识的得分与其自身受教育程度有相关性（ｒ＝０．３０１１，Ｐ＜０．０１）。年龄在３５岁以上的对象，营养知识的得分高于年轻人；三地区调查对象对营养知识的获取，合理的膳食模式，卫生的饮食习惯均持有积极、肯定的态度。食物消费频度调查结果表明，米／面、肉／禽、蔬菜、水果、奶及奶制品的消费量较高。此外，８９．５％，７８．８％和４７．８％的调查对象分别选择报纸、电视、广播作为其主要营养信息来源。本次调查为将来的营养宣教的内容和方法提供依据。     

P物质对肉芽组织成纤维细胞表皮生长因子的表达调控及其意义

目的 探讨感觉神经肽P物质(SP)对离体培养的肉芽组织成纤维细胞表皮生长因子(EGF)表达的调控作用及特点。方法 采用甲醛注射的方法造成Wistar大鼠局部无菌性炎性反应，提取肉芽组织进行成纤维细胞原代培养；采用逆转录—聚合酶链反应(RT—PCR)方法检测SP对肉芽组织成纤维细胞EGF基因表达的调控作用，观察时间及剂量—效应关系；采用Western-blotting方法检测EGF蛋白表达情况，观察时间及剂量—效应关系。结果 10^-7mol/L SP可诱导成纤维细胞EGF mRNA的表达，在作用后6h与对照组比，差异有显著性(P＜0．01)；SP在10^-8-10^-6mol/L范围内可以显著促进成纤维细胞EGF mRNA表达，在10^-7mol/L达到峰值，10^-5mol/L时与对照组差异无显著性(P＞0．05)。10^-7mol/L SP作用12h后可检测到EGF蛋白明显表达增强(P＜0．01)，24h达高峰，48h后逐渐有所回落。SP在在10^-8--10^-5mol/L范围可诱导EGF蛋白的表达，均在10^-7mol/L剂量点达到峰值(P＜0．01)。结论 SP可诱导肉芽组织成纤维细胞EGF基因和蛋白的表达，且呈现出一定的时间和剂量特点，在SP调控创伤愈合的作用中具有重要意义。