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51.
任平  黄熙  张莉  王跃民  王骊丽 《医学争鸣》2000,21(7):S157-S160
目的 探讨中药大复方体内作用规律 ,为“证治药动学”6要素中“定性定量论”提供进一步的实验依据 .方法 分别从冠状动脉定量狭窄犬和对照犬的右心房内给予复方川芎水提液 (0 .6 g· kg- 1 ) .结果 在动脉血药时 (c- t)曲线上出现了川芎嗪 (TMP)的双峰现象 ;冠状动脉狭窄犬的 TMP第 2峰显著地高于对照犬 ;而这种增高的第 2峰又与 TMP的血流动力学效应相关 .结论 可能存在机体生理和病理状态对中药复方体内命运的特殊处置规律  相似文献   
52.
Revascularization of the hypogastric artery often tends to be neglected in aortoiliac reconstructive surgery; however, its incomplete revascularization can result in unfavorable complications such as buttock claudication or necrosis, vascular impotence, and colonic ischemia. Multiple vascular lesions in the abdominal aorta and bilateral iliac arteries were reconstructed using a newly designed double bifurcated graft in five male patients. All five patients demonstrated excellent graft limb patency and postoperative improvement of the ankle-brachial pressure index without any clinical signs of ischemia in regions of the hypogastric artery. Thus, we conclude that an aggressive approach toward hypogastric circulation maintenance is essential in aortoiliac reconstructive surgery. By using this double bifurcated graft, rapid and safe revascularization of the bilateral hypogastric arteries concomitant with the external iliac or femoral arteries can be performed.  相似文献   
53.
Primary olfactory neurons located in the olfactory neuroepithelium project to the ipsilateral olfactory bulb and undergo a continuous process of neurogenesis and differentiation. We describe, in the adult rat, the kinetics of proliferation, differentiation and survival of primary olfactory neurons either in the presence or absence of their target, the olfactory bulb. The experimental design included unilateral bulbectomy, coupled with a single bromodeoxyuridine pulse 35 days after surgery. The rate of proliferation and survival of olfactory neurons was then examined by immunohistochemistry for bromodeoxyuridine, and the differentiation status by in situ hybridization for calmodulin messenger RNA in immature and mature olfactory neurons and immunohistochemistry for the dipeptide carnosine in mature olfactory neurons. We show that primary olfactory neurons can synthesize carnosine in the absence of the olfactory bulb. However, the number of carnosine-immunopositive neurons in the absence of their target is dramatically reduced to less than one-fourth, whereas the number of olfactory neurons expressing calmodulin messenger RNA is only slightly reduced. The numeric reduction of camosine-positive neurons in the target-deprived neuroepithelium is correlated with a dramatic reduction in the survival rate of olfactory neurons, since newly generated olfactory neurons are completely lost 35 days after the bromodeoxyuridine pulse. In contrast, in the normal olfactory neuroepithelium almost one-third of newly generated olfactory neurons survive 35 days after the bromodeoxyuridine pulse. On the whole, these data indicate that most of the primary olfactory neurons have a short lifespan but that once they have connected with the olfactory bulb they may persist longer, and suggest that throughout adulthood olfactory neurons are overproduced, differentiate independently from their target, and then undergo a process of target-induced neuronal selection.  相似文献   
54.
A prospective randomized trial was carried out to compare the long-term effects of triple therapy based on low-dose cyclosporin A (CyA), low-dose methylprednisolone (MP) and azathioprine (Aza) with three different double drug immunosuppressive regimens. After initial triple drug immunosuppression for 10 weeks, 128 patients were randomized into four different immunosuppressive groups: one group continued with triple therapy (group A) and the three other groups were treated with different combinations of two drugs: Aza and CyA (group B), Aza and MP (group C) and CyA and MP (group D). This report presents the 2-year results. For groups A, B, C and D, graft survivals were 75%, 78%, 84% and 81%, respectively, and patient survivals were 84%, 84%, 84% and 94%, respectively. After 2 years no patient had returned to dialysis in group C compared with one to three patients in every CyA-using group. However, at the end of the 2nd year, group C included more patients with deteriorating graft function than the other groups. Median serum creatinine was 107, 120, 139 and 129 mol/l for groups A, B, C and D, respectively. For the patients who remained on the original randomized protocol, there were no significant differences in graft function tests between the four groups, the median creatinine being 115, 115, 118 and 113 mol/l for groups A, B, C and D, respectively. Thus, no graft deterioration had occurred during the 2 years for these patients following the original protocol. Our results suggest that after initial triple therapy, patients with a first cadaveric kidney allograft can either continue with triple therapy or be converted to any of the double drug regimens without detriment to graft function, graft survival or patient survival for the next 2 years. This will allow more flexible and individual immunosuppressive treatment.  相似文献   
55.
This Capsular Lens (ONG, type IV, to be called O.C.L.) has been developed for routinely performed extracapsular cataract extraction with lens implantation. The fundamental surgical procedure was based on continuing experience with the bimanual aspiration-irrigation technique and system developed by the author in 1971. The biomechanical properties of the asymmetric partly flexible, haptic loops are designed to give tensionfree fixation in two capsular pockets. The plano-anterior position of the lens ensures well-defined irido-lenticular clearance and proper alignment of the convex side with the posterior capsule. Consequently no iridectomy or iridotomy is needed for proper aqueous flow.  相似文献   
56.
Information on premarital sexual attitudes of unmarried undergraduates was obtained from random samples on the same campus in 1968 and 1972. Students in 1972, compared with those in 1968, reported (1) more permissive attitudes toward premarital sexual behavior (both men and women), (2) fewer differences in attitudes between men and women, and (3) less adherence to the double standard. In contrast to earlier research on premarital sexual attitudes, these differences need not be due to the markedly different populations compared, or generalizable only to sociology and psychology students, or indicative of only those who chose to volunteer for study (volunteer bias).This research received support from the Institute for Research in Social Science and the University Research Council, University of North Carolina at Chapel Hill.  相似文献   
57.
加兰他敏片治疗阿尔采末病的多中心、随机双盲评价   总被引:15,自引:1,他引:15  
目的 :验证加兰他敏治疗轻、中度阿尔采末病 (AD)的疗效和不良反应。方法 :轻中度AD病人97例 ,其中 4 7例 [男性 2 1例 ,女性 2 6例 ,年龄 (72±s 6 )a],用加兰他敏 1片 ,po ,tid。另外 5 0例 [男性 2 7例 ,女性 2 3例 ,年龄 (71± 6 )a],用安慰剂 ,开始 1片 ,po ,tid。 2组治疗 1wk后 ,分别加至 2片 ,po ,tid。疗程为 8wk。以精神状态判断量表作疗效判断。结果 :加兰他敏组总有效率 5 3% ,安慰剂组为 18% ,加兰他敏组不良反应主要为胃肠道反应 ,多为恶心 ,呕吐等。结论 :加兰他敏组在认知功能、总体疗效等方面改善率均显著高于安慰剂组 ,对轻、中度AD病人治疗有效  相似文献   
58.
A simple method for the preparation of the inner liposomes for double liposomes (DL) was developed. The encapsulation efficiency of erythrosine in liposomes prepared by this new method is superior to that of the previous method because of the concentration of the drug in the lipid membrane. To evaluate the usefulness of DL prepared by the glass‐filter method modified in this study as an oral dosage form of salmon calcitonin (SCT), a suspension of liposomes containing SCT was administered to rats at a dose of 10 μg SCT/kg. Each type of DL showed better efficacy than its inner liposomes alone. The decrease in plasma calcium level was dependent on the electrical charge and particle size of the inner liposomes. The hypocalcemic efficacy of DL encapsulating SCT‐loading cationic liposomes relative to that after subcutaneous administration of SCT at a dose of 1 μg/kg was 6.47%, which was the largest value obtained. These results indicated that not only the particle size but also the electrical charge of inner liposomes affect intestinal absorption. This study verified that the efficacy was increased because of the decrease in diameter of the inner liposomes and the use of lipid with a positive charge. These findings concluded that DL might be useful as an oral dosage form of SCT. Drug Dev. Res. 58:253–257, 2003. © 2003 Wiley‐Liss, Inc.  相似文献   
59.
丹皮紫外指纹图谱共有峰率和变异峰率双指标序列分析   总被引:4,自引:0,他引:4  
目的:采用指纹图谱共有峰率和变异峰率双指标序列分析法分析丹皮类药材紫外指纹图谱。方法:本文用3种溶剂氯仿、无水乙醇及水,系统提取丹皮等不同极性区间成分,测定其紫外指纹图谱,研究样品的异同。结果:该方法可以准确对丹皮类药材进行细致的鉴别。结论:利用共有峰率和变异峰率双指标序列分析法可以对两个或多个样本进行可靠的鉴别。  相似文献   
60.
[目的]研究中性彗星分析法检测肿瘤细胞内在放射敏感性的可靠性和影响因素.[方法]人鼻咽高分化鳞癌细胞株CNE-1和人纤维肉瘤细胞株HT1080细胞,用6MV X线以0、100、200、300、400、600、800、1000cGy等不同剂量点照射,克隆形成法制定存活曲线,比较其放射敏感性的差异.然后进行两种细胞于600cGy照射后1、2、4、8h的中性彗星分析,以尾力矩为指标,动态检测不同时间点残留的DNA双链断裂,并与克隆形成分析结果相比较.[结果]克隆形成分析法显示CNE-1细胞的放射敏感性低于HT1080细胞,其2Gy照射后存活分数(SF2)和平均致死剂量D0值分别为0.397、0.331和1.898、1.287.两种细胞在照射后1、2、4h的中性彗星尾力矩分别为0.148±0.106、0.100±0.083、0.058±0.043和0.297±0.179、0.157±0.092、0.092±0.060,各时间点之间有显著性差异(P<0.05),但差别逐渐减小;照射后2h和4h的尾力矩比值分别为0.637和0.630,与SF2比值和D0比值的倒数(0.834和0.678)较接近;两种细胞照射后8h的尾力矩比较差异无显著性.[结论]中性彗星分析法与克隆形成分析法的检测结果有确切的相关性,照射后一定时间内的残留DNA双链断裂有可能成为检测肿瘤细胞放射敏感性的指标.  相似文献   
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