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61.
PURPOSE: Pressor responses are reflexly evoked by the activation of groups III and IV muscle afferents, which are also known to mediate nociceptive responses. In this experiment, the effects of analgesic balm (AB) application on these responses were investigated without the interference of other types of anesthesia or effects from the higher brain. METHODS: Heart rate (HR), blood pressure, and end-tidal CO(2) were monitored in midcollicularly decerebrated cats. Static contractions (30 s) of hindlimb muscles were evoked by electric stimulation of L7 and S1 ventral roots. After control runs, a commercial AB (1% capsaicin, 12.5% methyl salicylate) was applied to the skin surface over the contracting muscles. Muscle contractions were evoked every 10 min, alternating between the two hindlimbs. RESULTS: Changes in mean arterial pressure (MAP) evoked by static ipsilateral muscular contraction were significantly attenuated 20 min and 40 min after AB application. The decreases in the pressor response were significant at both the initial and the last parts of the stimulus intervention after 20 min of AB application. There were no significant changes in the response to contraction of the hindlimb contralateral to the AB application. Application of AB to the contralateral leg did not add to the ipsilateral effects. CONCLUSIONS: AB application to the skin surface over contracting muscles significantly decreased autonomic responses to static muscular contraction. This effect was independent of higher cortical processing and strongly suggests that application of methyl salicylate and capsaicin on the skin has analgesic effects on signals from receptors located in muscle.  相似文献   
62.
血府逐瘀汤对乳鼠心肌细胞缺血再灌注损伤的影响   总被引:4,自引:0,他引:4  
目的为探讨血府逐瘀汤对乳鼠心肌细胞缺血再灌注损伤的影响。方法应用培养的乳鼠心肌细胞造成缺血再灌注损伤的动物模型,观察心肌细胞中超氧化物岐化酶(SOD)的水平,推断细胞内活性氧的生成量;观察培养液中乳酸脱氢酶(LDH)活性改变以判断细胞损伤情况;并进行DNA琼脂糖凝胶电泳及末端脱氧核苷酸介导的脱氧尿苷三磷酸缺口末端标记法(TUNEL),以判断细胞死亡类型及程度。结果血府逐瘀汤可显著升高缺血再灌注时SOD的水平,显著降低LDH的水平。DNA电泳图谱表明:血府逐瘀汤可使DNA的拖尾基本消失;TUNEL显示血府逐瘀汤可显著减少缺血再灌注所致的心肌细胞死亡。结论血府逐瘀汤有保护缺血再灌注时心肌细胞免于死亡之功效。  相似文献   
63.
Data on body composition in conjunction with reference centiles are helpful in identifying the severity of growth and nutritional disorders in infancy and for evaluating the adequacy of treatment given during this important period of rapid growth. Total body fat (TBF) and fat-free mass (FFM) were estimated from total body electrical conductivity (TBEC) measurements in 423 healthy term Caucasian infants, aged 14-379 days. Cross sectional age, weight, and length related centile standards are presented for TBF and FFM. Centiles were calculated using Altman's method, based on polynomial regression and modelling of the residual variation. The TBF percentage steeply increased during the first half year of life, and slowly declined beyond this age. Various simple TBEC derived anthropometric prediction equations for TBF and FFM are available to be used in conjunction with these standards. Regression equations for the P50 and the residual SD, depending on age, weight, or length, are provided for constructing centile charts and calculating standard deviation scores.  相似文献   
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Roxatidine acetate, a new H2 receptor antagonist, was compared with ranitidine in the treatment of duodenal ulcers in a double-blind multicentre study. Eighty-four patients with endoscopically proven duodenal ulcer were randomized to receive 150 mg roxatidine acetate or 300 mg ranitidine at bedtime. Repeat endoscopy was performed after 4 weeks (25–33 days) and if the ulcer had not healed, another endoscopy was performed after a further 4 weeks of treatment. Using per protocol analysis 73.6% of ulcers treated with roxatidine healed at 4 weeks compared to 72.2% of ulcers treated with ranitidine (P=NS). The healing rates at 8 weeks were 92% with roxatidine and 83.3% with ranitidine (P=NS). Using equivalence tests, the healing rate of roxatidine was found to be equivalent to that of ranitidine within a 20% region. Roxatidine users took significantly less antacids than ranitidine users (P < 0.05). There were no significant adverse effects due to roxatidine or ranitidine. Roxatidine is a safe effective drug in the treatment of duodenal ulcers with a healing rate comparable to that of ranitidine.  相似文献   
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Inhalation of calcium trisodium diethylenetriaminepentaacetate (Ca-DTPA) increases the removal of plutonium and other transuranics from the body. Data are required to determine possible biological effects from inhaled DTPA. p]Female rats were given a single or 12 daily, 2–4-h, inhalation exposures to aerosols of 10, 20 and 40% Ca-DTPA and the lungs were examined at 21 and 42 days following the last exposure. No pulmonary pathology was found from the single inhalation treatment with Ca-DTPA while only a slight, peripheral, histiocytosis was observed in the lungs of multiple-treated rats. There was no significant effect of DTPA treatments on body weight, lung weight, hematology or serum chemistry values.  相似文献   
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The extent to which lateral genetic transfer has shaped microbial genomes has major implications for the emergence of community structures. We have performed a rigorous phylogenetic analysis of >220,000 proteins from genomes of 144 prokaryotes to determine the contribution of gene sharing to current prokaryotic diversity, and to identify "highways" of sharing between lineages. The inferred relationships suggest a pattern of inheritance that is largely vertical, but with notable exceptions among closely related taxa, and among distantly related organisms that live in similar environments.  相似文献   
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