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991.
The effects of intraventricular administration of lysine-vasopressin on pain sensitivity in the rat were determined in the tail-flick test. Vasopressin (16–100 μg) was found to induce potent and dose-dependent antinociceptive actions, lasting up to one hour. An additional experiment demonstrated that analgesia induced by vasopressin was not blocked by naloxone, suggesting that this analgesia is independent of opiate receptor systems. Vasopressin was also found to be equally effective in elevating tail-flick latency after systemic administration. These results, together with others, suggest a possible role of vasopressin systems in the regulation of pain sensitivity.  相似文献   
992.
993.
Enumeration of potentially pathogenic bacteria from sewage sludges.   总被引:9,自引:8,他引:1       下载免费PDF全文
To ascertain the health risks that may be posed by the land application of sewage sludges, a scheme was devised to determine the types and numbers of pathogenic and potentially pathogenic bacteria present in sludges. A processing treatment was adapted to sludge to give a homogenate which yielded the greatest numbers of viable bacteria. Conventional methods were successful in enumerating Klebsiella, Staphylococcus, gram-negative enteric bacteria, and commonly used indicator organisms. Modifications of conventional methods improved the enumeration of Salmonella, Mycobacterium sp., fluorescent Pseudomonas sp., and Clostridium perfringens. However, Shigella methodology yielded only one isolate. Utilizing the proposed scheme, the population densities of these organisms were estimated in three domestic wastewater sludges. In light of these results, the potential impact of land application of sewage sludges is discussed.  相似文献   
994.
995.
We analyzed the pattern of correlations among fitness components, herbivory, and resin characteristics in a natural all-aged stand of ponderosa pine, to infer the strength and mechanism of natural selection on plant chemistry. Male and female cone production were monitored yearly for 15 years, and levels of herbivory for 9 years in 165 trees. Resin flow rate and monoterpene composition were determined for these same trees. Multiple regression of fitness components on resin characteristics showed significant associations consistent with directional selection for increased resin flow rates and increased proportions of α- and β-pinene, myrcene and terpinolene. However, negative correlations among monoterpene fractions of the resin constrained the overall selection. Selective herbivory by aphids approached statistical significance and monoterpenes showed some (non-significant) effect as deterrents against deer browse. Resin characteristics were not correlated with attack by cone insects or porcupines. However, the association between resin characteristics and fitness is significantly different from that predicted by the path coefficients involving herbivores. Therefore the hypothesis that these herbivores mediate selection on the resin is not supported by the observed pattern of correlations among resin characteristics, herbivory, growth and fecundity. In this population, most of the association between resin characteristics and fitness appears to be mediated by some other factor independent of attack by herbivore species present. Received: 18 March 1996/Accepted: 18 July 1996  相似文献   
996.
A double-blind controlled trial in 24 lepromatous leprosy patients in reaction showed that clofazimine (Lamprene) controlled symptoms of erythema nodosum leprosum reaction in lepromatous leprosy better than prednisolone. Clofazimine also appeared to be significantly superior in preventing recurrence once the reaction had been controlled. There was a statistically significant rise in serum albumin among inpatients on clofazimine as compared with patients on prednisolone, but no difference in terms of neurological status, bacterial index, morphological index, and renal functions. Red/black hyperpigmentation was seen among practically all patients on clofazimine. No other side-effects or deleterious systemic effects were observed.  相似文献   
997.
998.
999.
A number of recombinant cell lines which produce human tissue plasminogen activator (tPA) was obtained using different hosts--mouse, rat, hamster, simian and human cell lines. All types of recombinant lines secreted active r-tPA into conditioned medium. A slight difference between molecular weights of secreted variants of r-tPA was mediated by the different mechanisms of protein modification. Treatment of some recombinant cell lines with different substances resulted in increased levels of r-tPA production.  相似文献   
1000.
Interactions of luciferases isolated from Vibrio fischeri 6 and Escherichia coli JM109(pF3) (bearing cloned V. fischeri luxAB genes) with FMN reductase isolated from E. coli JM109 were studied. FMN reductase formed a stable complex with luciferase, suggesting similar properties of the FMN reductases in the taxonomically close families Vibrionaceae and Enterobacteriaceae.  相似文献   
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