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61.
白细胞介素-8(IL-8)作为中性粒细胞趋化因子和促血管生成因子,受到人们的重视。研究表明,IL-8促进卵细胞的发育、成熟,诱发排卵;在输卵管和子宫内膜的表达随月经周期而变化;参与胚泡着床和胚胎发育。本文综述IL-8在哺乳动物生殖过程中的重要作用。  相似文献   
62.
BACKGROUND: A low level of response to alcohol has been associated with both the genetic constitution of the regulatory region (SLC6A4) of the human serotonin (5-hydroxytryptamine, 5-HT) transporter (5-HTT) and with future alcohol intake and an increased risk for alcoholism. To date, all studies of relevant polymorphisms have been carried out in populations in the United States. METHODS: Data were extracted from a subset (n = 243) of a cohort of children who have been observed since birth through evaluation of the family history of alcoholism and psychosocial risk influences. At age 16 years, the response to alcohol was assessed with the Self-Rating of the Effects of Alcohol (SRE) questionnaire, and the average amount of alcohol intake per month was assessed during the prior 6 months. Additional variables that were measured included the 5-HTT genotype, externalizing behavior, and sociodemographic variables, such as gender and age. RESULTS: The level of response to alcohol was significantly lower among carriers of two long alleles of the 5-HTT regulatory region compared with carriers of one or two short alleles (Mann-Whitney U = 5225.0, p = .005). In a multiple regression analysis, the level of response to alcohol and externalizing behavior but not psychosocial factors significantly predicted the average amount of alcohol intake per month. CONCLUSIONS: This study demonstrates that, independent of the assessed psychosocial variables, the 5-HTT genotype correlated with the level of response to alcohol and predicted alcohol intake among 16-year-old adolescents.  相似文献   
63.
The long-term cost of effective management for benign prostatic hyperplasia (BPH) remains an important issue in pharmacoeconomics because about 25% of men aged 50 yr and older experience voiding problems due to BPH. With the ageing population and the increase in the percentage of patients with BPH for whom any type of treatment can be considered, a substantial increase in total costs to society can be expected. The up-front costs of interventional approaches to BPH are being replaced by a pattern of long-term medical and preventive therapy. The age-adjusted rate of transurethral resection of the prostate (TURP) reached a high point in 1987 and TURP rates, but not costs, have been in decline ever since. Mean 1-yr treatment costs (medical therapy and TURP) have been estimated in a pan-European study to be 858 Euros per patient, 75% of which were medication costs. Using a 2-yr time frame for treatment, Medicare costs for finasteride, terazosin, and TURP have been estimated as $3874, $2161, and $1820, respectively. The available models of the total long-term cost for all therapies for BPH remain compromised by a lack of inclusion of indirect costs, the lack of true long-term data and, critically, the lack of human cost information (patient preference). Only medical therapy provides a preventive as well as symptomatic potential and, if all of the issues were fully incorporated, it is likely that medical therapy would be increasingly recognised as economically preferable.  相似文献   
64.
IIEF-5与NEVA检测在阴茎勃起功能障碍诊断中的意义   总被引:2,自引:2,他引:0  
目的探讨应用国际勃起功能评分5(IIEF-5)问卷表结合夜间阴茎勃起测定系统(NEVA)筛选勃起功能障碍(ED)的可行性及意义。方法148例门诊ED病人,应用IIEF-5问卷表评分,再通过NEVA测定仪监测夜间阴茎勃起情况,次日数据输入主机回放并分析。结果93例为心理性ED;在19~69岁的5个年龄组中,重度ED的比例由11.8%到55.0%,NEVA中度异常者IIEF积分(12.98±2.58)分,NEVA重度异常者IIEF积分(7.32±1.04)分。结论NEVA能有效地鉴别心理性与器质性ED,IIEF-5评分值与NEVA检测阴茎勃起时血容量变化值有相关性。IIEF-5与NEVA检测结合,能提高诊断和评估ED的可靠性。  相似文献   
65.
目的 探讨白细胞介素 10 (IL 10 )在过敏性紫癜血管内皮损伤中的作用及机制。方法 建立人脐静脉内皮细胞 (HUVEC)培养模型 ,ELISA法检测过敏性紫癜患儿外周血单个核细胞 (PB MC)活化后培养上清IL 6、IL 1β、TNF α、IL 10等细胞因子的含量 ;AnnexinV/PI双染色法 ,流式细胞仪检测过敏性紫癜患儿PBMC培养上清所诱导的内皮细胞凋亡率。结果 ①过敏性紫癜组PBMC体外刺激活化后IL 6、IL 1β、TNF α、IL 10等细胞因子的分泌量均明显高于对照组 (P <0 0 1) ,其培养上清诱导的内皮细胞凋亡率 (34 7± 10 3) %明显高于对照组 (3 6± 0 9) %。②抗IL 6、IL 1β、TNF α单克隆抗体联合阻断可明显降低过敏性紫癜患儿PBMC培养上清诱导的内皮细胞凋亡率 (2 2 6±5 9) % ,而抗IL 10单克隆抗体阻断则明显增加过敏性紫癜患儿PBMC培养上清诱导的内皮细胞凋亡率 (5 6 9± 16 5 ) %。③于过敏性紫癜患儿PBMC培养上清加入外源性IL 10 ,可明显降低IL 6、IL 1β、INF α等炎性细胞因子的表达 ,并明显降低内皮细胞凋亡率 (11 8± 3 1) %。结论 IL 10作为机体炎症反应负反馈调节过程中的一个重要枢纽 ,在过敏性紫癜炎症因子所介导的血管内皮损伤中起重要的保护作用。  相似文献   
66.
鸡抗内毒素卵黄抗体IgY的制备   总被引:2,自引:1,他引:1  
目的:研究分别应用内毒素(LPS)、类脂A(LipidA)和大肠杆菌突变株15免疫鸡后其蛋黄中抗内毒素抗体IgY的产量、纯度、效价并筛选最佳免疫抗原。方法:分别应用内毒素(LPS)、类脂A(LipidA)和大肠杆菌J5突变株作为抗原免疫25周龄Leghom鸡,水溶法(WD)提取蛋黄中抗体IgY,双紫外光测定抗体含量,SDS-PSGE电泳检测抗体纯度,细胞酶联染色和ELISA检测抗体特异性、效价及筛选最佳免疫抗原。结果:3种抗内毒素IgY含量和效价分别为14.4mg/ml和1:12 800(J5)、10.61mg/ml和1:12 800(LPS)、9.26mg/ml和1:3200(LipidA),抗体纯度均为95%左右。结论:大肠杆菌突变株J5和内毒素(LPS)为最佳免疫抗原,免疫鸡后其蛋黄中抗内毒素抗体IgY的产量和效价最高。  相似文献   
67.
Selective protection of the normal host tissues from the toxic effects of anticancer agents would allow the use of higher, probably more effective, doses of the drugs. It has been demonstrated that delayed high-dose uridine administration after 5-fluorouracil decreases the extent of myelosuppression and causes faster regeneration of the bone marrow. We studied the biochemical consequences of the gastrointestinal toxicity caused by 5-fluorouracil and the potential of high-dose uridine treatment to influence these adverse effects. 5-Fluorouracil caused dose-related decreases in the biochemical parameters (thymidine kinase, sucrase, maltase, alkaline phosphatase) selected as early markers of the impaired metabolic activity of the intestinal mucosa. The nadir of the biochemical changes was reached between 24 h and 72 h after 5-fluorouracil treatment, and complete regeneration of the mucosa took 6–7 days. Delayed high-dose uridine administration failed to mitigate the severity of the gastrointestinal damage that ensued after 5-fluorouracil treatment, but caused significantly earlier regeneration of the mucosa.  相似文献   
68.
Four hundred and twenty-three alcohol dependent subjects were enrolled into a 12-week randomized, double-blind, placebo-controlled study to determine the safety and efficacy of the 5-HT2 receptor antagonist, ritanserin (2.5 mg/day or 5 mg/day), in reducing alcohol intake and craving. All subjects received 1 week of single-blind placebo prior to randomization into the 11-week double-blind phase. Additionally, all subjects received weekly individual sessions of manual-guided cognitive-behavioral therapy. Comparing the single-blind period with endpoint, there was approximately a 23% reduction in drinks/day; 34% fall in the total number of drinking days/week; 22% decrease in drinks/drinking day; and a 37% diminution in alcohol craving for all treatment groups. All treatment groups experienced a beneficial clinical outcome as assessed by the Clinical Global Impression Scale. There was, however, no significant difference between treatment groups on any of these measures of alcohol drinking, craving, or clinical outcome. Subjects were of relatively high social functioning at baseline, and this did not change significantly during treatment. Treatment groups did not differ significantly on either medication compliance or reported adverse events. Ritanserin treatment was associated with a dose-related prolongation of subjects’ QTc interval recording on the electrocardiogram. These results suggest that alcohol dependent subjects can show marked clinical improvement within a structured alcohol treatment program. These findings do not support an important role for ritanserin in the treatment of alcohol dependence. Received: 30 April 1996/Final version: 3 July 1996  相似文献   
69.
周向东  周维善  王钟麒   《药学学报》1997,32(6):416-419
报道新化合物A-失碳-17β-羟基-17α-乙炔基-Δ3(5),9(10)-雌甾二烯-2-酮2的合成。文中探讨了用炔钾粗品对A-失碳-Δ3(5),9(10)-雌甾二烯-2,17-二酮1和A-失碳-6β,19-环氧-Δ3-雄甾-2,17-二酮3的选择性炔化,分别得标题化合物2(44%)及A-失碳-17β-羟基-17α-乙炔基-6β,19-环氧-Δ3雄甾-2-酮4(65%),4经还原性破开环氧、去羟甲基和去醋酰氧基合成了标题化合物2。四步总收率为34%。  相似文献   
70.
Serotonin (5-HT) is a mediator (through 5-HT1P receptors) of slow EPSPs in myenteric ganglia of the small intestine. The effect of 5-HT can be mimicked by elevating cAMP; therefore, we tested the hypothesis that the slow EPSP-like response to 5-HT is cAMP-mediated. Guinea pig gut was enzymatically dissociated; myenteric ganglia remained intact and were collected by filtration. Neurons in the isolated ganglia retained their ability to manifest the slow EPSP-like response to 5-HT. Exposure to 5-HT raised the ganglionic level of cAMP (ED50 0.3 μM). This effect was not antagonized by the 5-HT1P antagonist, N-acetyl-5-hydroxytryptophyl-5-hydroxytryptophan amide (100.0 μM), or mimicked by the 5-HT1P agonist, 5-hydroxyindalpine (10.0 μM). Increases in cAMP were also evoked by the 5-HT1 agonist, 5-carboxyamidotryptamine (10.0 μM), the 5-HT2 agonist, (±)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI; 1.0–10.0 μM), and by the 5-HT4 agonists, renzapride (1.0–10.0 μM) and 5-methoxytryptamine (1.0–10.0 μM); however, neither the 5-HT1/5-HT2 antagonists, spiperone, methysergide, and methiothepin, nor the 5-HT4 antagonist, tropisetron (ICS 205–930; 10.0 μM), were able to inhibit the rise in cAMP evoked by these compounds or by 5-HT (0.1–10.0 μM). The 5-HT-evoked elevation of cAMP was antagonized by ketanserin (10.0 μM), which also blocked the effects of 5-methoxytryptamine and DOI, but not those of renzapride. The effective concentration of DOI, however, was higher than that needed for activation of 5-HT2 receptors, and Northern analysis using a cDNA probe encoding the rat 5-HT2 receptor failed to reveal the presence of 5-HT2 mRNA in myenteric ganglia, although it hybridizes with mRNA of the right size in the guinea pig brain. Compounds that failed to change levels of cAMP or to antagonize the action of 5-HT included 8-hydroxy-di-n-propylamino tetralin, R58639, R88226, and sumatriptan. It is concluded that the receptor responsible for the 5-HT-induced rise in cAMP in ganglia isolated from the guinea pig myenteric plexus is not a known subtype of 5-HT receptor. Since the pharmacology of this novel receptor is different from that of the slow EPSP-like response to 5-HT, the receptor probably does not mediate the slow EPSP. © 1993 Wiley-Liss, Inc.  相似文献   
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