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141.
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143.
醋氨酚缓释包衣颗粒研究   总被引:1,自引:0,他引:1  
包衣颗粒体外溶出试验证明在释放量达66%以前为零级恒速释放,此后释放速率降低为非零级释放。颗粒在室温下密闭贮存21个月后,释放速率增快,但仍为零级释放,也是在释放量达66%以后转变为非零级释放。用尿药排泄速率法研究了包衣颗粒的体内动力学并与常规片剂作比较,并测出两者的消除速率常数。常规片剂所得药物t 1/2=3.21h,而包衣颗粒剂所得半衰期约延长2.5倍。通过吸收百分率与体外溶出百分率在不同时间下数值的比较得到线性关系,相关系数r=0.9886。说明体外溶出数据可以作为控制吸收率的依据。按一级吸收一室模型公式计算了一定剂量下的血药浓度,在13h以内血药浓度都在治疗浓度范围(5~20μg/ml)以内。最高浓度为10.5μg/ml,达峰时间为3.27h。本品一次服1.1g可延效12h。  相似文献   
144.
This study was undertaken to evaluate the use of transrectal sonographically guided fine-needle aspiration biopsy and to compare sonographic with digital guidance for biopsy. In 62 patients in whom prostatic carcinoma was suspected at digital rectal examination, fine-needle aspiration biopsies were performed transperineally under sonographic guidance and transrectally under digital guidance. These patients had 89 nodules, 73 of which were sampled with both techniques. Malignant cells were obtained under digital guidance in 17 of 73 nodules (23%) and under sonographic guidance in 16 (22%). An additional seven nodules, which were not seen sonographically, were sampled under digital guidance and proved to be negative. In nine other nodules that were nonpalpable and evident only with sonography, malignant cells were obtained under sonographic guidance in three. These findings indicate that sonographic guidance for fine-needle aspiration biopsy is as good as digital guidance for palpable lesions.  相似文献   
145.
硝基甘油对狗缺血区冠脉循环的作用   总被引:1,自引:0,他引:1  
用实验性犬冠脉狭窄模型,冠脉内恒流灌注硝基甘油0.5μg/kg.min-1,使冠脉血流量(CBF)增加、远端小动脉压(DCP)、冠脉血管总阻力(RT)、小冠脉血管阻力(RS)及冠状静脉低切血粘(ηb)减少;而主动脉压和心率无明显变化。恒流灌注硝基甘油1μg/kg.min-1时,在开始5min内冠脉循环的变化同上,并伴大冠脉血管阻力(RL)减少,10 min后出现CBF减少和RT,RL及ηb增加。结果提示,硝基甘油有缓解和加重心肌缺血的双重作用,其作用可能与剂量张扩张远端小动脉压的程度有关。  相似文献   
146.
Neofissure after lobectomy of the right lung: radiographic and CT findings   总被引:1,自引:0,他引:1  
Seo  JB; Lee  KS; Choo  SW; Shim  YM; Primack  SL 《Radiology》1996,201(2):475
  相似文献   
147.
Female drug dependants (n = 171) and controls (n = 1137) were studied to search for psychiatric morbidity in them. The psychiatric morbidity was found to be 36.3% and 6.9%, respectively. The most common psychiatric disorder found was dysthymic disorder followed by adjustment disorder, anxiety disorder and borderline personality disorder. The diagnosis was significantly dependent on the type of drug used (P < 0.001) and HIV seropositivtty status of the patients (P = 0.04). The findings highlight the relationship of the psychiatric morbidity to the HIV status and female drug users.  相似文献   
148.
Previously, we have demonstrated age-associated alterations in transmembrane signaling. One of the most reproducible alterations found in the immune response with aging is the decrease of lymphocyte proliferation on stimulation with various different mitogens. Here, we confirm that proliferative responses to stimulation with phytohaemagglutin (PHA), recombinant human IL-2, or anti-CD3 monoclonal antibody are all greater in the young (20-25 years) than old (60-87 years) population. We attempted to modulate the proliferative response using various agents acting at different levels of transmembrane signaling (pertussis toxin, cholera toxin, isoproterenol, PMA, Ca ionophore A23187), as well as at the level of the lymphocyte plasma membrane (methyl-beta-cyclodextrin, MBCD), or by using antioxidant vitamins (Vitamin E or C). None of these agents was able to restore effectively the proliferative response of lymphocytes from the aged to the level of young subjects. Even the combination of A23187 and PMA acting directly on calcium metabolism and protein kinase C activity was insufficient to restore the decreased mitogenic capacity of T cells from elderly subjects. Cyclodextrin, which decreases the cholesterol content of the membrane, increased the proliferative response of lymphocytes of elderly subjects, but not to the level of the young. Vitamin E had a very strong inhibitory effect on lymphocyte stimulation in both the age groups, except in combination with MBCD in T cells of the elderly, while Vitamin C had no significant modulatory effect. MAPK ERK and p38 activation was found to be decreased with aging in T cells after anti-CD3 mAb stimulation. Vitamin E but not Vitamin C strongly inhibited MAPK ERK or p38 activation. The direct activation of certain molecules or the modulation of the cholesterol content of the membrane seems to be effective immunomodulatory interventions with aging.  相似文献   
149.
小藤铃儿草的生物碱成分   总被引:1,自引:0,他引:1  
自小藤铃儿草Dactylicapnos torulosa(Hook.f ct Thomas.)Hutchins中分得六个单体,通过UV,IR,MS,~1HNMR和~(13)CNMR解析,鉴定了四个,其中一个为新化合物,命名为紫金龙碱(zijinlongine,Ⅰ),其他三个为已知化合物:氯化1-甲氧基小檗碱(1-methoxylberberium chloride,Ⅱ),氯化三乙基苯胺(triethylphcnylamium chloride,Ⅲ)和异紫堇定(isocorydine,Ⅳ)。Ⅱ和Ⅲ系首次从植物中得到。  相似文献   
150.
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