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91.
The authors developed a union sponsored 2-day human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) "train the trainer" program for healthcare workers in the San Francisco Bay Area. The program incorporated the "education for action" approach in an effort to respond to the inadequacies in many traditional, institutional trainings. Service Employees International Union (SEIU) and Labor Occupational Health Program (LOHP) conducted the HIV/AIDS "train the trainer" program for approximately 100 healthcare workers in county public hospitals and community health clinics. After completing the program, these workers went back to their healthcare facilities, or community organizations, and led additional classes on HIV/AIDS transmission and prevention for approximately 600 more people. The goal of the program was to empower healthcare workers to: 1) identify the occupational risks associated with exposure to blood and potentially infectious body fluids at the workplace; 2) develop strategies to reduce those risks; 3) discuss their feelings about caring for an HIV/AIDS patient; and, 4) conduct HIV/AIDS workshops at the workplace.  相似文献   
92.
A number of androgen effects on epithelial cells may be mediated by androgen-regulated paracrine factors produced by underlying mesenchymal cells. In previous studies we demonstrated that prostatic stromal cells and testicular peritubular cells, derived from immature rats, produce mediators of androgen action with identical effects on Sertoli cells. In the present paper we further compared the morphological and functional characteristics of both mesenchymal cell types. Cultured prostatic stromal cells and testicular peritubular cells look identical under phase-contrast microscopy, share the ability to form tubular structures and "balls" when cocultured with Sertoli cells, and contain proteins immunoreactive with an antiserum against alpha-smooth muscle isoactin. Two-dimensional gel electrophoresis shows that the pattern of proteins produced by both cell types is nearly identical. Conditioned media from stromal and peritubular cells contain a factor that stimulates transferrin and cGMP production in Sertoli cells. The behavior of the active principle in the media from both cell types is comparable. On reverse-phase HPLC the elution profile of this factor is comparable for media from both cell types. In conclusion, these data point to a striking similarity in the morphological and functional characteristics of mesenchymal cells cultured from the prostate and testis.  相似文献   
93.
Summary In a controlled crossover study, identical surgical procedures, the prophylactic removal of bilateral non-erupted 3rd molar teeth, were performed on two separate occasions in 24 healthy patients. Prior to each procedure, either betamethasone 9 mg (Celeston Chronodose®) or placebo was administered intramuscularly, in a randomized fashion. Objective and subjective assessments were recorded for paired comparison of the post-operative course, including swelling, pain, trismus, local temperature, bleeding, wound-healing and preference for treatment. In 23 patients, less swelling occurred when betamethasone was given pre-operatively. The mean reduction on the 3rd and 6th post-operative days was 55% (p<0.001) and 69% (p<0.001), respectively. Pain assessments (visual analogue scale) were significantly lower after the corticosteroid injection; mean response: 1st evening 17 vs 56 mm, 2nd evening 5 vs 37 mm, and 3rd evening 2 vs 13 mm. No significant correlation between the steroid-induced reduction in swelling and pain could be made. This may indicate that dissociation may exist between pain and other inflammatory events like swelling. No clinically apparent infection or other disturbance of wound-healing was noted after corticosteroid administration. This treatment course was preferred by 23 of the 24 patients.  相似文献   
94.
Summary Free cholesterol in lipids from the scalp and hair is predominantly a constituent of epidermal lipids. Therefore, a reduction in cholesterol content induced by a drug indicates a reduction in cell turnover in the epidermis. As, according to the literature, increased cell turnover in the epidermis results in formation of dandruff, a reduction in the proportion of cholesterol should indicate inhibition of the formation of dandruff. Conversely, an increase in free cholesterol should generally indicate a keratolytic effect. So unequivocal an interpretation has not so far been possible in persons with dandruff, as it was not known whether free cholesterol was increased or decreased. In addition, this interpretation was not possible after use of antimicrobial substances, as in vitro investigations had failed to exclude microbial esterification of cholesterol on the scalp. The present investigation has shown that correlation of free cholesterol level with cell turnover is permissible in patients with dandruff, even if antimicrobial drugs are being tested.  相似文献   
95.
Quipazine, a serotonin receptor stimulant, inhibited the response of rats to painful stimuli in two methods currently used to measure antinociception in these animals: the hot plate and tail compression test. The antinociceptive action was observed with doses ranging from 5 to 20 mg/kg i.p. according to the test situation.The effect was significantly antagonized by a pretreatment with methergoline, a potent serotonin antagonist. An electrolytic lesion placed in the nucleus raphe medianus, which produced a marked decrease of serotonin in the forebrain did not, or only slightly, affected the effect of quipazine, depending on the method used to measure antinociception.It is suggested that quipazine can produce antinociceptive action in rats by interacting with a serotonergic mechanism. The action appears to be due mainly to a direct action on postsynaptic serotonin receptors, although a presynaptic component can also contribute to the effect of quipazine.Visiting scientist from Clinica Neurologica, UniversitàVisiting scientist from Clinica Neurologica, Università  相似文献   
96.
Previous results suggest that norepinephrine decreases growth hormone (GH) release in goldfish by means of alpha-2 adrenoceptor activation. The intracellular mechanisms by which norepinephrine inhibits GH release were examined in the present study using dispersed goldfish pituitary cells. In 2-h static incubation experiments, norepinephrine and the alpha-2 agonist clonidine decreased basal GH release and the GH responses to stimulation by the dopamine D1 agonist SKF38393 and two native gonadotropin-releasing hormones (GnRH). Norepinephrine also reduced GH responses to the adenylate cyclase activator forskolin, two protein kinase C (PKC) activators (phorbol ester and synthetic diacylglycerol), and two Ca2+ ionophores (ionomycin and A23187). Similarly, norepinephrine applied as a 1-h pulse in cell column perifusion experiments reduced basal GH release and abolished the GH response to a 5-min pulse of arachidonic acid. In goldfish, D1-stimulated GH release is mediated by AC-, arachidonic acid-and Ca2+-dependent pathways, whereas GnRH action is coupled to PKC-and Ca2+-dependent mechanisms. These results suggest that norepinephrine activation of alpha-2 receptors inhibits ligand-induced GH secretion by actions subsequent to activation of these second messenger cascades. To further characterize norepinephrine mechanisms of action on unstimulated hormone release, the ability of norepinephrine and an alpha-2 agonist to affect activation of two second messenger cascades under basal conditions was also investigated. Static incubation with clonidine reduced cAMP production in a time-and dose-dependent manner, suggesting that norepinephrine inhibitory action can also be expressed at the level of cAMP production. Resting intracellular free calcium levels in single, identified goldfish somatotropes was unaffected by norepinephrine. However, the inhibitory effects of norepinephrine on basal GH secretion was not observed in the presence of a voltage-sensitive Ca2+ channel agonist. Whether these channels are targets for norepinephrine action on unstimulated GH release requires further investigation.  相似文献   
97.
川芎嗪及其衍生物对羟自由基的清除作用   总被引:29,自引:0,他引:29  
目的:探讨川芎嗪及其衍生物对羟自由基的清除作用。方法:应用Fenton反应检测并计算50%羟自由基被清除时的药物浓度(EC_(50))。结果:结果显示对羟自由基均有明显清除作用,且呈剂量依赖关系。川芎嗪及其衍生物与苯甲酸和甘露醇的清除作用差异有极显著性(P<0.01),而相互间作用无明显差异(P>0.05)。结论:川芎嗪及其衍生物对羟自由基有明显的清除作用。  相似文献   
98.
目的:观察糖尿病对大鼠坐骨神经动作电位潜伏期的影响。方法:剥离大鼠坐骨神经,利用BL-310生物信号处理系统测量其动作电住的潜伏期。结果:糖尿病大鼠坐骨神经动作电位潜伏期约为0.92ms,比正常大鼠动作电位潜伏期延长。  相似文献   
99.
红毛五加药理作用研究进展   总被引:15,自引:0,他引:15  
目的对红毛五加药理作用研究进展进行全面综述。方法根据相关文献 ,按照药理作用分类汇总。结果红毛五加具有抗肿瘤、抗炎、抗病毒、保肝、镇痛、增强免疫功能等作用。结论红毛五加具有很强的药用开发潜力  相似文献   
100.
血管抑素的研究近况   总被引:4,自引:0,他引:4  
综述了有关血管抑素及其受体、作用方式、影响作用的因素等问题的研究现状,并对其在肿瘤的治疗和新药开发中的意义进行了展望。  相似文献   
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