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71.
口服糖皮质激素大鼠皮肤组织形态学变化   总被引:4,自引:0,他引:4  
目的:观察口服糖皮质激素大鼠皮肤形态学改变,为建立新的皮肤衰老动物模型提供形态学上的依据。方法:实验于2006-07/2007-02在广东医学院药理教研室组织药理实验室完成。①实验对象:20只SD雄性SPF级大鼠随机分为两组,糖皮质激素组和空白对照组,每组10只。②实验方法:糖皮质激素组每天口服灌胃糖皮质激素3.5mg/(kg·d),空白对照组每天口服灌胃同等剂量生理盐水,喂养100d后麻醉下处死大鼠,取背部正中1cm×1cm大小皮肤组织检测相关指标。③实验评估:常规苏木精-伊红染色、VanGieson染色法、Weigert-间苯二酚-碱性品红染色法观察皮肤组织形态改变,并用计算机图像分析系统定量分析表皮厚度和弹力纤维总面积。结果:纳入结果分析16只,其中空白对照组8只,糖皮质激素组8只。糖皮质激素组大鼠皮肤表皮变薄,弹力纤维面积减少,胶原纤维多断裂,排列疏松,糖皮质激素组大鼠表皮厚度(33.8±3.1)μm,弹力纤维总面积(3557.9±373.1)μm2,均小于对照组大鼠表皮厚度(63.7±7.4)μm,弹力纤维总面积(5049.0±497.5)μm2。结论:糖皮质激素3.5mg/(kg·d)口服灌胃100d可导致大鼠皮肤衰老样改变,与人类皮肤衰老有相似形态学表现。  相似文献   
72.
目的使用非线性成长率理论分析人眼视力发展规律。方法使用高斯光学及成像方程推导出两个参数:屈光状态改变率(M)及眼轴成长率(N),用以预测MOS(初始近视)、年龄(A^*)及其后视力的发展情况。结果当有效焦距F=(21-22)、密码M=(2.67—2.9)(D/mm)时,此计算值符合实验平均值(2.7)。当年龄A^*=(3,6)岁的屈光度变化已知时,我们计算其MOS预测年龄为A^*=(7.3,21.8)岁(在不同条件下)。此值反比于M值在A=6及A=3的比值或N=N—N^*,即非正视态及正视态的眼轴成长率之差。本理论也可用来预测在年龄A=25时的近视度,分别为D=-14及-0.49的上述两例情况,同时也能分析Lain等人的测量值(由出生到青年期的视力发展情况)。结论本理论可预测MOS、其后发展情况及其符合实验值(M)。使用成长率差值(dN)比使用L/rl比值能更准确地预测MOS。  相似文献   
73.
目的提高医院临时处方溃结Ⅰ号保留灌肠剂的稳定性,并对其中的主要成分含量进行控制。方法制备时加入助悬剂,用沉降容积比和再分散性选择适宜的助悬剂及其最佳助悬浓度,并用紫外分光光度法对主要成分柳氮磺吡啶的含量进行测定。结果在制剂中加入卡波母作为助悬剂0.15%就可以达到良好的助悬效果,而且制备的制剂再分散性好。结论加入卡波母作为助悬剂制备的制剂稳定,再分散性好,便于使用和保存。  相似文献   
74.
The triphenylethylene-type antiestrogens, such as tamoxifen, are known to be useful in the treatment of estrogen-dependent tumors. However, these compounds display mixed estrogen agonist/antagonist activity which may limit their therapeutic effectiveness. This problem of mixed activity led to the synthesis and identification of a cyclopropyl derivative of cis-stilbene which we have named Analog I. This compound (1,1-dichloro-cis-2,3-diphenylcyclopropane) displayed only antiestrogenic activity in the mouse. The present study was designed to evaluate cyclopropyl derivatives of Analog II for estrogenic and antiestrogenic activity in the rat using the standard 3-d uterotropic assay and the uterine cytoplasmic estrogen receptor assay. Five compounds (B-F) which are cyclopropyl derivatives of stilbene, stilbenediol, and phenanthrene were evaluated in this study. Three of the compounds (B-D) displayed neither estrogenic nor antiestrogenic activity in the rat. The relative estrogenic activities of E and F were 11.3 and 1.5%, respectively, of diethylstilbestrol in the uterotropic assay, and 39 and 6.2%, respectively, of estradiol in the estrogen receptor assay. Neither E nor F was found to display antiestrogenic activity in the rat. The results indicate that the relative estrogenic and receptor binding activities of E and F are similar to those previously observed in the mouse, while B-D appear to be inactive in both species.  相似文献   
75.
应用放射配基结合法测定了人参皂甙Rb1和Rg1α1,α2,β肾上腺素能受体、M胆碱能受体、5-羟色胺、多巴胺及GABA等七种受体的作用。结果均不能证明它们对这七种受体有亲和力。但给动物ip药物连续5天,Rb1和Rg1均能使中枢M胆碱受体密度显著增高。Rb1及Rg1还能显著增加脑内蛋白质的含量。上述实验结果对解释人参的中枢作用提供了重要证据。  相似文献   
76.
OBJECTIVE: To evaluate radiotherapy dose and length of treatment in the control of early stage nasopharyngeal carcinoma (NPC) treated with a combination of external radiotherapy and brachytherapy, MATERIALS & METHODS: We reviewed the records of 133 patients with early stage nasopharyngeal carcinoma (stage I or II, AJC/UICC staging system) who received definitive radiotherapy in Chang Gung Memorial Hospital from 1979 to 1991. The median follow-up time was 7.1 years with a minimum of 2 years. All patients were treated with megavoltage external radiotherapy to the nasopharynx area (63-72 Gy) followed by high dose rate intracavitary brachytherapy (5-16.5 Gy in one to three fractions, spaced 1-2 weeks apart). The median total dose and time of irradiation was 75 Gy (69.8-81.4 Gy) and 11.6 weeks (7.8-20 weeks) respectively. Survival analysis was used to examine the effect of several variables on prognosis. RESULTS: The 5-year rates were 86.4% for local control, 84.7% for disease free survival, 88.5% for actuarial survival and 84.2% for overall survival. The treatment group (combination of time and dose of irradiation) was the most important prognostic factor according to Cox's proportional hazard model. Patients receiving radiation at a total dose of < or = 75 Gy completed in < 12 weeks showed the best prognosis. CONCLUSION: Treatment time and total treatment dose are both important factors in treating early stage NPC. Decreasing the total radiation time to < 12 weeks and not exceeding a radiation dose of 75 Gy gave the best results.   相似文献   
77.
OBJECTIVE To investigate the expression of Coxsackie and Adenovirus receptor (CAR) in renal-cell carcinoma and the relationship of the CAR to the biological behavior of the carcinomas.METHODS The immunohistochemical SP method was used to detect the expression of Coxsaekie and Adenovirus receptor in 48 cases of renalcell carcinoma and in 12 cases of normal renal tissue 2 cm away from the tumor tissue.RESULTS The positive rates of CAR were 100% in 12 cases of para-tumcr normal renal tissue and 35.4% in 48 cases of renal-cell carcinoma respectively. The difference of CAR expression between them was significant (P<0.05). The grades of the tumor were as follows: 22 in Grade Ⅰ, 17in Grade Ⅱ and 9 in Grade Ⅲ with the CAR positive rate being 54.5%,23.5% and 11.1%, respectively. There was a negative correlation between CAR expression and tumor grading (P<0.05). In addition, the number of the cases in stages Ⅰ to ⅣV were 19, 13, 11 and 5 respectively, with the respective positive rates being 57.9%, 30.8%, 18.2% and 0.0%, i.e. there also was a negative relationship between CAR expression and the stage (P<0.05).CONCLUSION CAR expression is down-regulated in renal-cell carcinoma compared with normal tissue. The level of CAR may be a sensitive predictor of differentiation, invasion and metastasis. Loss of CAR expression correlates with the invasive phenotype in our analysis of renal-cell carcinoma.  相似文献   
78.
79.
Diverse materials with varying physical and magnetic properties have been evaluated as gastrointestinal contrast agents for magnetic resonance (MR) imaging. Uniform marking of the small bowel remains the greatest challenge. Ferrites are magnetically active iron oxide particles that are miscible with water and cause loss of signal on MR images. The decrease in MR signal intensity produced by ferrites occurs with a wide range of iron concentrations (0.1-10 mM) and with both T1- and T2-weighted pulse sequences. These effects of ferrites are explained by predominant T2 shortening with negligible T1 effects. The ferrite preparation used in this study was stable in vitro, with little iron solubilized by acid. Intragastric administration of ferrite (5 mg of iron per kg in 6 ml) routinely marked the small bowel of rats. The authors conclude that ferrites represent a promising new class of contrast agents for gastrointestinal MR imaging.  相似文献   
80.
Intestinal obstruction proximal to a transition zone without an interposed physical barrier usually indicates Hirschsprung disease. The authors report one case of focal small bowel muscular thinning just distal to a transition zone that produced clinical and radiographic findings that simulated long-segment Hirschsprung disease in a 2-day-old infant.  相似文献   
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