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21.
研究了卡尔曼滤波紫外分光光度法测定复方新诺明片和增效联磺片中各组分的实验条件,结果复方新诺明片平均回收率分别为100.4±0.2%(SMZ)和100.4±0.5%(TMP);增效联磺片平均回收率分别为99.5±0.7%(SMZ)、100.8±0.6%(SD)和99.2±0.6%(TMP)。  相似文献   
22.
微囊化吲哚美辛片剂的研讨   总被引:2,自引:0,他引:2  
以明胶-CAP 为囊材,经复凝聚法制备吲哚美辛微囊,再按所筛选的最佳处方制备微囊化片剂。该片与市售片相比,体外 T_(50)延长约5.6倍,家兔体内达峰时间滞后,能明显减轻对大鼠胃的刺激性。  相似文献   
23.
This study was undertaken to explore whether intervention withheparin and aspirin (H/A) in selected patients undergoing in-vitrofertilization (TVF) and embryo transfer could improve fecundityrates. Specifically, it explored the possibility that womendiagnosed with organic pelvic disease who demonstrated antiphospholipidantibodies (APA) could benefit from H/A administration in asimilar manner to that used in patients with recurrent pregnancyloss. We used an enzyme–linked immunosorbent assay forsix different phospholipids to identify patients who expressedAPA before they underwent IVF/embryo transfer. This study wasconfined to the first IVF/embryo transfer cycle that followedassessment of APA status and accordingly, the number of IVF/embryotransfer cycles corresponds with the number of patients treated.APA seropositive patients were treated with aspirin, 81 mg orallyq.d., and heparin 5000 IU s.c. b.i.d., beginning on day 1 ofcontrolled ovarian stimulation. The endpoint for success wasa live birth or an ultrasound confirming fetal cardiac activity(a viable pregnancy). The prevalence of APA in patients diagnosedwith organic pelvic disease (53%) was much higher than in thosewithout female pathology (14%). The administration of H/A toAPA seropositive patients significantly (P < 0.05) improvedthe viable pregnancy rate (49%) compared to the untreated APAseropositive group (16%). The viable pregnancy rate for APAseropositive women treated with H/A was also significantly (P< 0.001) higher than for untreated APA seronegative patients(27%). We conclude that all women undergoing IVF/embryo transfershould be tested for APA prior to initiating ovarian stimulation,and those with APA seropositivity should be treated with H/A.  相似文献   
24.
目的 观察阿司匹林对大鼠慢性压迫性脊髓损伤后神经细胞凋亡及神经功能恢复的影响。方法选择65只体重为220~250g的Wistar大鼠(雌雄不限),于T10部位置入后路渐进式压迫装置,制作成慢性压迫性脊髓损伤模型。随机分为阿司匹林治疗组(A组,30只)、生理盐水对照组(B组,30只)和假手术组(C组,5只)。应用原位末端脱氧核糖核苷酸转移酶介导dUTP标记技术,分别于慢性压迫性脊髓损伤后1、3、7、14、28d做行为学评价,并取材对脊髓损伤区进行细胞凋亡检测。结果A、B组均发现细胞凋亡,A组与B组细胞凋亡率相比差异有显著性(P〈0.05),A组与B组行为学评价相比差异有显著性(P〈0.05),神经细胞凋亡情况与运动功能改变具有相关性。结论 阿司匹林对慢性脊髓压迫损伤后所导致的神经细胞凋亡产生抑制作用。  相似文献   
25.
26.
目的:研究原料药粒径等对盐酸普萘洛尔渗透泵片释药行为的影响。方法:取不同批号盐酸普萘洛尔及同批号重结晶前、后的原料药均按相同处方制备成渗透泵片,考察药物体外释放情况及释药24h后衣膜形态;并对上述不同原料药的粒径分别以光学显微镜和激光粒度分析仪进行证实。结果:以原料药粒径较小的渗透泵片释放完毕后衣膜变形,且不能维持零级释放,原料药粒径较大的渗透泵片结果与之相反。不同原料药经仪器证实粒径确有差异。结论:原料药的粒径可影响制备的渗透泵片的释放行为,提示性状稳定的原料药的合理选择在制剂过程中不可忽视。  相似文献   
27.
目的 观察清前方对大鼠慢性非细菌性前列腺炎的作用。方法 采用向大鼠前列腺内注入1%角叉菜胶生理盐水的方法,建立实验性非细菌性前列腺炎模型,并将实验大鼠随机分为4组,分别给予相应剂量的蒸馏水(A组和B组)、清前方(C组)或舍尼通(D组)混悬液,观察清前方对该炎症模型大鼠体重增长变化、前列腺脏/体比值及病理学改变的影响。结果 清前方(2.5g/kg·d)组炎症模型动物体重增长回升,前列腺脏/体比值下降,前列腺平滑肌增殖受到抑制,局部病理性瘀血状态得以改善。结论 清前方可望用于治疗慢性非细菌性前列腺炎。  相似文献   
28.
Introduction: Inflammation in the airways in connection to asthma is complex and the mechanisms underlying the associated clinical symptoms involve the interaction of many different kinds of cells and mediators, giving rise to different phenotypes. Objective: The objective of the present thesis was to investigate the molecular and cellular mechanisms that result in two of these phenotypes, i.e. aspirin‐intolerant asthma (AIA) and allergic asthma. The main focus was on leukotrienes. Materials and Methods: (i) Thirty‐three subjects with diagnosed AIA were challenged with celecoxib, a selective inhibitor of cyclooxygenase (COX)‐2. (ii) With the ultimate objective of finding a marker that could be used to identify patients with leukotriene‐associated asthma, the capacity to produce leukotrienes and the responsiveness to inhaled leukotrienes were determined in 20 subjects with mild asthma and in 10 healthy control individuals. (iii) Eight individuals with mild allergic asthma were challenged repeatedly with low doses of allergen in an experimental model aimed at mimicking the natural exposure to allergen. Exhaled nitric oxide was measured throughout the study. (iv) Thirteen patients with allergic asthma were subjected to bronchial challenges with methacholine and leukotriene D4 (LTD4) prior to and after administration of 500‐µg fluticasone twice daily for 2 weeks, and their levels of exhaled nitric oxide and urinary leukotriene E4 (LTE4) were determined. Results: (i) Both escalating doses from 5–100 mg (administered in a blinded, placebo‐controlled study) and an open‐label challenge with 200 + 200 mg celecoxib were tolerated well by AIA individuals. (ii) Neither group exhibited a correlation between the formation of leukotriene B4 by their whole blood in response to ex vivo stimulation or urinary levels of LTE4 and airway responsiveness to LTD4. (iii) The level of nitric oxide in the air that they exhaled rose significantly. At the same time, these subjects did not report any symptoms of asthma, did not require rescue by bronchodilator medication, and did not display any change in the calibre of their airways. (iv) Inhalation of glucocorticoid attenuated the responsiveness to methacholine and reduced the level of exhaled nitric oxide, but neither the responsiveness to LTD4 nor urinary excretion of LTE4 was affected. Conclusions: (i) This finding indicates that the intolerance reaction leading to broncho‐constriction in patients with AIA is caused by inhibition of COX‐1 and, furthermore, provides a scientific basis for administration of selective inhibitors of COX‐2 to alleviate prostaglandin‐mediated pain and inflammation in these patients. (ii) In further attempts to predict which asthmatic patients will respond well to anti‐leukotriene treatment, investigations on the capacity for leukotriene synthesis, responsiveness to these agents and expression of their specific receptors in the lungs are being performed. (iii) Monitoring of exhaled nitric oxide on a daily basis may allow for early detection of exacerbation in subjects with allergic asthma. (iv) Neither the release nor the actions of leukotrienes appear to be sensitive to inhaled glucocorticoids, strengthening the rationale for using a combination of glucocorticosteroids and anti‐leukotrienes to treat allergic asthma.  相似文献   
29.
本文应用高效液相色谱法测定了8名健康受试者自身交叉服用炎痛喜康普通片与控释片(分别服用单剂量20mg)后的血药浓度。用非线性最小二乘模型嵌合的计算机程序对数据进行处理,表明该药在体内为一室模型,并求得各项参数如下:普通片,k_a=1.568h~(-1),k=0.0191h~(-1),V=7.9201,t_(max)=4.4h,C_(max)=2.502μg/ml,AUC=150.04h·μg/ml;控释片,ka=0.185h~(-1),k=0.0223h~(-1),V=7.3561,t_(max)=15.3h,C_(max)=2.048μg/ml,AUC=129.63h·μg/ml.  相似文献   
30.
BACKGROUND: The percentage of diabetic patients who do not benefit from the protective effect of aspirin is larger than in other populations at cardiovascular risk. OBJECTIVE: We compared the ability of aspirin to suppress TxA2 and platelet activation in vivo, in type-2 diabetics vs. high-risk non-diabetic patients. METHODS: Urinary 11-dehydro-TXB2, plasma sCD40 L, and sP-selectin were measured, together with indices of low-grade inflammation, glycemic control, and lipid profile, in 82 patients with type-2 diabetes and 39 without diabetes, treated with low doses of aspirin. RESULTS: Urinary 11-dehydro-TxB2, plasma sCD40L and sP-selectin were significantly higher in diabetics than in controls: [38.9 (27.8-63.3) vs. 28.5 (22.5-43.9) ng mmol(-1) of creatinine, P = 0.02], [1.06 (0.42-3.06) vs. 0.35 (0.22-0.95) ng mL(-1); P = 0.0001], [37.0 (16.8-85.6) vs. 20.0 (11.2-35.6) ng mL(-1), P = 0.0001], respectively. The proportion of individuals with diabetes increased across quartiles of 11-dehydro-TxB2, sCD40L, and sP-selectin, with the highest quartiles of 11-dehydro-TxB2, sCD40L and sP-selectin, including 66%, 93.3%, and 93.3% of individuals with diabetes. Markers of platelet activation positively correlated with indices of glycemic control but not with markers of low-grade inflammation. CONCLUSIONS: Platelet dysfunction associated with insufficient glycemic control, may mediate persistent platelet activation under aspirin treatment.  相似文献   
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