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991.
Inhaled therapy using a metered‐dose inhaler (MDI) with attached spacer has been increasingly recognized as the optimal method for delivering asthma medication for acute attacks and chronic prophylaxis. However, in developing countries the cost and availability of commercially produced spacers limit the use of MDI‐spacer delivery systems. A 500‐ml plastic bottle has been recently adapted to function as a spacer. This article reviews the current data on the efficacy of this bottle‐spacer and discusses its advantages and limitations. It is concluded that a modified 500‐ml plastic bottle is an effective spacer; modification and use of this device should be incorporated into international guidelines for the management of children with asthma.  相似文献   
992.
原发性胆囊癌CD44v6和bcl-2的表达及其与临床病理的关系   总被引:1,自引:0,他引:1  
目的 探讨CD44v6和bcl 2蛋白在原发性胆囊癌组织中的表达及其与癌组织类型、病理分级和转移状况的关系 ,以及CD44v6表达与bcl 2表达的相关性。方法 应用免疫组织化学方法检测 50例原发性胆囊癌、2 0例胆囊腺瘤和 1 0例慢性胆囊炎组织中CD44v6和bcl 2蛋白的表达。结果 胆囊癌组织中CD44v6和bcl 2表达阳性率分别为82 .0 %和 60 .0 % ,均明显高于胆囊腺瘤 (分别为 45 .0 %和 30 .0 % ,P<0 .0 5) ,并随着胆囊癌细胞分化程度的减低、病理分级的增高和转移而明显增高 (P<0 .0 5)。同时 ,CD44v6的表达与bcl 2表达呈正相关 (r =0 .36 ,P<0 .0 5)。结论 CD44v6和bcl 2均是胆囊癌高度恶性和预后不良的重要指标。胆囊癌CD44v6表达与bcl 2蛋白表达可能具有相互协同作用。  相似文献   
993.
The effect of ACTH and/or adrenalectomy on serotonin (5-HT)2 receptor binding sites was evaluated in the neocortex of rat forebrain. One day after the adrenalectomy or sham operation, ACTH (50 µg/day) was injected subcutaneously into adult male SD rats for 10 consecutive days. Saturation analysis showed that subchronic ACTH treatment significantly increased the Bmax values for3H-ketanserin binding without any change in the Kd values. Moreover, this ACTH-induced increase in the Bmax values was prevented by adrenalectomy. The concentrations of 5-HT and 5-hydroxyindole acetic acid (5-HIAA) measured by HPLC-ECD were not altered by these manipulations. Ten-day administration of corticosterone (20 and 50 mg/kg) also increased 5-HT2 receptor density in the neocortex of rat forebrain. 5-HT2 (and 5-HT1C) receptor agonist, (±)DOI-induced wet-dog shakes in ACTH and/or adrenalectomy-treated rats were also examined. Ten-day administration of ACTH enhanced (±)DOI-induced wet-dog shakes and this increase was prevented by adrenalectomy. These results indicate that subchronic adrenocorticotropinadrenal axis activation of rats increases both the number of 5-HT2 receptors in neocortex of forebrain and the wet-dog shake responses induced by (±)DOI.  相似文献   
994.
The effects of withdrawal from continuous administration of cocaine on behavioral sensitivity to apomorphine and monoamine receptor density were examined in rats. Subdermal minipumps that delivered either saline or 20 mg/kg/day cocaine hydrochloride were implanted for 2 weeks. Apomorphine-induced stereotypy (0.5 mg/kg, SC) was examined in separate groups of rats either 4 hr or 7, 28, or 60 days after removal of the minipumps. Transient enhanced sensitivity to apomorphine-induced stereotypy occurred during the course of withdrawal. Animals withdrawn from cocaine for 4 hours did not differ from controls in their sensitivity to apomorphine, whereas animals withdrawn from cocaine for 7 days exhibited an increase in apomorphine-induced oral stereotypy relative to controls. However, the enhanced stereotypy response was no longer evident in animals withdrawn for 28–60 days. The animals were sacrificed after behavioral testing, and their brains were assayed for changes in monoamine receptor density in the frontal cortex, caudate-putamen, and nucleus accumbens. The density of 3H-SCH-23390-labeled D1 receptors was altered in all three regions examined in a time-dependent manner that paralleled the changes in behavioral sensitivity to apomorphine. There was a transient decrease in D1 receptor density that was evident by 7 days following withdrawal from continuous cocaine administration and was no longer evident 28 or 60 days posttreatment. There were no changes in 3H-spiroperidol-labeled D2 receptors, 125-pindolol-labeled β-adrenergic receptors, or 3H-ketanserin-labeled 5-HT2 receptors in any of the regions examined at both 4 hr and 7 days after termination of the cocaine infusion. These findings are discussed in terms of their relevance to developing pharmacologic treatments for withdrawal from cocaine. © 1994 Wiley-Liss, Inc.  相似文献   
995.
中华伍氏百叶散抗大鼠肝癌的实验研究   总被引:1,自引:0,他引:1  
目的 :研究中华伍氏百叶散 (WSBYS)的抗癌作用。方法 :通过大鼠体重 ,肝脏病理学为指标 ,观察WSBYS对 2 -乙酰氨基芴 (2 -FAA)诱导的大鼠肝癌的治疗作用。结果 :服用WSBYS治疗的大鼠 ,肝癌病变程度低于阳性对照组 ,体重高于阳性对照组 ,且与剂量大小呈正相关。结论 :WSBYS对 2 -FAA诱导的大鼠肝癌有明显的治疗作用  相似文献   
996.
程靖  孙宏慧  周和 《循证医学》2003,3(4):204-207
目的 评价变应性鼻炎、哮喘患者血清中白细胞介素IL-4、IL-6、IL-8检测指标的意义。方法 检索策略:通过中国生物医学文献数据库(CBMdisc)、中文全文数据库全面检索国内已发表的相关文献。选择标准:中国成人变应性鼻炎、哮喘患者与对照组血清白细胞介素IL-4、IL-6、IL-8水平检测。资料收集和分析:由2位评价者按照上述检索策略收集文献。排除那些不符合选择标准要求的试验。结果 经Meta分析,发作期、缓解期变应性鼻炎患者血清中IL-4水平分别较对照组上升129.45 ng/mL(95%CI 124.95~133.96)、35.00 ng/mL(95%CI 32.01~39.78),有显著统计学意义(P<0.000 01):缓解期IL-6水平较对照组上升21.87 ng/mL(95%CI 19.83~23.91),有显著统计学意义(P<0.000 01);发作期、缓解期IL-8水平分别较对照组上升41.75 ng/mL(95%CI 29.14-54.36)、98.94 ng/mL(95%CI 96.48-101.41),有显著统计学意义(P<0.000 01);发作期IL-4水平较缓解期上升129.99 ng/mL(95%CI 125.00~134.99),有显著统计学意义(P<0.000 01)。结论 IL-4、IL-6和IL-8参与了变应性鼻炎、哮喘的发生和促进了变态反应性疾病的发展,有必要开展更广泛研究和更深层的原因探索。  相似文献   
997.
AStudyoftheMechanismofYinzhihuang(菌栀黄)InjectionintheTreatmentofInfantileHepatitisSyndromeDongYong-sui(董永绥);HuangZhi-hua(黄志华);...  相似文献   
998.
采用放射免疫法测定实验性胆道炎症兔胆系组织以及几种胆道疾患病人胆系组织中6-keto-PGF1α与TXB2的含量。结果显示:动物模型组与病人组的上述两指标均显著增高;AOSC病人的TXB2增高更明显,而胆道梗阻病人胆管组织无此变化。提示前列腺素类及血栓素对胆道炎症的发生可能有关,TXB2的负性作用尤为重要。  相似文献   
999.
Astrocytes respond to the excitatory neurotransmitter glutamate with dynamic spatio-temporal changes in intracellular calcium [Ca2+]i. Although they share a common wave-like appearance, the different [Ca2+]i changes--an initial spike, sustained elevation, oscillatory intracellular waves, and regenerative intercellular waves--are actually separate and distinct phenomena. These separate components of the astrocytic Ca2+ response appear to be generated by two different signal transduction pathways. The metabotropic response evokes an initial spatial Ca2+ spike that can propagate rapidly from cell to cell and appears to involve IP3. The metabotropic response can also produce oscillatory intracellular waves of various amplitudes and frequencies that propagate within cells and are sustained only in the presence of external Ca2+. The ionotropic response, however, evokes a sustained elevation in [Ca2+]i associated with receptor-mediated Na+ and Ca2+ influx, depolarization, and voltage-dependent Ca2+ influx. In addition, the ionotropic response can lead to regenerative intercellular waves that propagate smoothly and nondecrementally from cell to cell, possibly involving Na+/Ca2+ exchange. All these astrocytic [Ca2+]i changes tend to appear wave-like, traveling from region to region as a transient rise in [Ca2+]i. Nevertheless, as our understanding of the cellular events that underlie these [Ca2+]i changes grows, it becomes increasingly clear that glutamate-induced Ca2+ signaling is a composite of separate and distinct phenomena, which may be distinguished not based on appearance alone, but rather on their underlying mechanisms. © 1994 Wiley-Liss, Inc.  相似文献   
1000.
The glucose clamp technique is currently regarded as the standard test for measuring insulin sensitivity against which other methods are compared but is unsuitable for routine screening of patients outside a hospital base. There is thus a need for a simpler test to measure insulin sensitivity. We have therefore compared the glucose disappearance rate KITT in the first 15 min of the insulin tolerance test (ITT) with the M and M/I values derived from the standard euglycaemic clamp in nine normal subjects and eight subjects with Type 2 (non-insulin dependent) diabetes mellitus and coexisting obesity. All subjects underwent the ITT and euglycaemic clamp in random order. Nine subjects later had a repeat ITT to determine the reproducibility of the test. In the ITT, 0.1 U kg-1 body weight, human Actrapid insulin was given as an IV bolus and simultaneous arterialized and venous blood samples were obtained every minute for 15 min. The first order rate constant for the disappearance of glucose KITT over the period 3-15 min was taken as a measure of insulin sensitivity. The euglycaemic clamp was performed with an insulin infusion of 50 mU kg-1 h-1 for 120 min and a variable rate glucose infusion to maintain blood glucose concentration at 0.5 mmol l-1 below fasting level to minimize the effect of endogenous insulin secretion. The ratio of the mean rate of glucose infused (M, mumol kg-1 min-1) to the plasma insulin over the last 30 min of the clamp was taken as a measure of tissue sensitivity to insulin (M/I) assuming endogenous glucose output was suppressed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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