马克思关于人类社会阶段“跨越”发展的辩证法

马克思曾设想俄国农村公社有可能跨越资本主义制度“卡夫丁峡谷”而直接进入共产主义社会。本文运用马克思主义理论辩证地阐述了人类社会实现跨越发展所必备的条件内在因素、外在条件、动力以及跨越的内容。     

Heroin in the United Kingdom: different forms, different origins, and the relationship to different routes of administration

Heroin exists in the United Kingdom in several different forms, which vary not only in their country of origin and purity, but also in their suitability for use by either injecting or by 'chasing the dragon'. The availability of these different forms of heroin has varied considerably over time. A review of the characteristics and availability of these various forms of heroin in recent years is presented, accompanied by consideration of their probable intended use by injection or by 'chasing the dragon'. Samples of black market heroin in the salt form are usually used by injection, whereas the base form is usually taken by 'chasing the dragon'. The heroin yield to the drug user from samples of heroin taken by 'chasing the dragon' varies according to its base or salt format and according to the presence of other drugs in the sample. Heroin samples from different countries of production mostly conform to either base or salt form. Novel approaches at the macro level to prevention and control of heroin-related problems through influence upon this complex heroin market-place should now be considered.     

Modulation of immunoglobulin production and cytokine mRNA expression in peripheral blood mononuclear cells by intravenous immunoglobulin

Intravenous immunoglobulin (IVIG) has the potential to regulate Ig production, but the mechanism(s) responsible for this effect is unknown. In experiments reported here, we examined the ability of IVIG to regulate Ig production in human peripheral blood mononuclear cells (PBMCs) stimulated with pokeweed mitogen (PWM). IVIG (2–10 mg/ml) showed a potent (80–85%) inhibition of PWM-stimulated IgG, IgM, and IgA production. To determine more precisely how IVIG mediated the inhibition of Ig production, we studied Ig promoting cytokine gene expression after PWM stimulation with or without IVIG (2 and 10 mg/ml) using dot-blot techniques. RNA was isolated from PBMCs at predetermined time points and probed with cDNAs specific for human cytokines (IL-1-, IL-2, IL-2R, IL-4, IL-5, IL-6, -IFN, and TNF-). IL-6 mRNA accumulation was maximal at 4.5 hr post-PWM stimulation and was inhibited 64–75% when IVIG (10 mg/ml) was present. -IFN mRNA levels peaked at 72 hr poststimulation and were also 68–75% inhibited by IVIG. IL-2 mRNA levels peaked at 4.5 hr and were 23–46% inhibited by IVIG. The inhibitory effect of IVIG on production of these cytokines (IL-6 and -IFN) was also observed at the protein level in sonicated PBMCs after incubation with PWM and IVIG. The mRNA levels for other cytokines were not or only minimally inhibited by IVIG. Addition of IL-6, -IFN, or IL-2 partially restored Ig production in IVIG-treated PWM-stimulated cultures, suggesting that inhibition of other cytokines or another mechanism(s) independent of cytokine inhibition might also be involved, although inhibition of IL-6, -IFN, and IL-2 may be one of the critical factors in the suppression of Ig production by IVIG.     

Insulin concentrations and insulin sensitivity after short-term amiloride in healthy subjects

We have evaluated the short-term effects of amiloride on insulin action in vivo, since amiloride is known to impair insulin action in vitro.Seven healthy subjects were treated according to a randomized, double-blind, cross-over protocol. The treatment periods were 3 days each with amiloride 15 mg daily and placebo. Insulin action on glucose turnover was assessed directly after each treatment period with the hyper-insulinaemic euglycaemic glucose clamp technique.At the two insulin concentrations studied ( 30 mU·l^–1 and 200 mU·l^–1), the glucose infusion rate required to maintain constant euglycaemia did not differ after either amiloride or placebo. The rates of glucose production and utilization were also similar, whereas the so-called insulin sensitivity index at the lower insulin concentration was significantly reduced (by about 15 %) after amiloride. Moreover, amiloride produced significantly higher fasting insulin and C-peptide concentrations, whereas fasting glucose and NEFA concentrations were unaltered.In conclusion, these data suggest that short-term amiloride slightly impairs insulin sensitivity with respect to glucose uptake. However, overall glucose homoeostasis does not appear to be affected, probably due to a compensatory rise in plasma insulin.     

Metabolic base production and mucosal vulnerability during acid inhibition in a mammalian stomachin vitro

Acid inhibition increases gastric mucosal susceptibility to damage by luminal acid. This might be due to reduced metabolic CO₂ and bicarbonate whereas, during normal acid, secretion cytoprotective CO₂/HCO₃- production parallels acid production. Metabolic activity and mucosal damage caused by luminal acid perfusion was determined in anin vitro mouse stomach, with and without acid inhibition, and at 0%, 1%, or 5% serosal CO₂ supply. Without acid inhibition there was no mucosal damage at any level of serosal CO₂/HCO₃- supply. Acid inhibition reduced metabolic CO₂ production by 29% (P<0.004) and resulted in microscopic damage to 55% of the mucosal area and perforation in four of five stomachs (P<0.05). Although, 1% CO₂ supply completely replaced the reduction in metabolic CO₂, it did not protect against mucosal damage. Overreplacement by 5% serosal CO₂/HCO₃- was required to prevent damage. There was no correlation between luminal CO₂/HCO₃- output and mucosal damage. The protection by endogenous or exogenous CO₂/HCO₃- appears to act intracellularly rather than by intragastric or intercellular neutralization.This study was supported by Swiss National Foundation grants 32-26369.89 and 32-33626.92. The morphometry equipment was supported by a grant from the Osterreichische Nationalbank.     

白花蛇舌草研究进展

本文综述了近年来白花蛇舌草的资源与生产、化学成分、药理作用、临床应用等方面的研究进展，为白花蛇舌草深入研究提供参考。     

左氟沙星市场透析

目的 :了解我国左氟沙星市场现状及发展趋势。方法 :对左氟沙星的国内、外生产和销售情况进行分析 ,进而预测其市场前景。结果与结论 :我国左氟沙星市场前景广阔 ,竞争日趋激烈 ,工商企业应密切注意市场变化。     

阳离子抗菌肽研究进展

阳离子抗菌肽广泛分布于多种生物 ,越来越多的证据表明它们在机体天然免疫中有着重要的作用。广谱抗菌、抗病毒、抗肿瘤细胞及其它特性也使得其具有潜在的医药价值。对抗菌肽的研究正不断深入。该文从一般性质、作用机制、构效关系、重组表达、应用价值、存在的问题与发展方向等方面 ,对阳离子抗菌肽的最新研究进展进行综述     

青霉素过滤工艺改进

目的：为了进一步解决青霉素生产过过程中的过滤问题和进一步扩大产量，克服原设备的缺陷。方法：我们采用了目前国内制药企业广泛使用的鼓式过滤机过滤技术及利用热交换器进行热量交换以达到生产工艺的要求同时改进相应工艺。结果：达到降低生产成本、扩大生产产量、加快生产速度，提高生产产率的结果。结论：通过实际生产证明完全符合实际生产的需要。本文就目前青霉素过滤过程中的几个关键环节作简要讨论。