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61.
Postembolic colonic infarction   总被引:12,自引:0,他引:12  
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62.
1. Infusion experiments were performed on chronically catheterized conscious rats to assess kidney function before and after the induction of diabetes mellitus with streptozotocin. 2. Two infusion regimens were used, a conventional constant-infusion protocol and a novel computer-driven, servo-controlled fluid replacement technique. The latter enables body fluid status to be maintained throughout a study occasion by servo-controlled replacement of spontaneous urinary fluid losses. 3. The chronically catheterized conscious rat infused using a servo-controlled system appears to be the optimum model for a study of diabetic renal function. The conscious preparation circumvents problems associated with anaesthesia and acute surgery. The servo-controlled infusion protocol maintains the altered fluid status of the diabetic condition. Both hyperfiltration and polyuria, characteristics of human diabetes often absent in anaesthetized and/or constantly infused diabetic rats, were seen in all conscious servo-controlled diabetic animals. 4. The new regimen enables a more accurate assessment of renal function in experimental diabetes than with previous protocols. It should prove useful in future studies, particularly those assessing the role of anti-diabetic drugs on the kidney.  相似文献   
63.
A family is described in which 2 siblings born to healthy parents presented with abnormal facies, persistent diarrhoea, and early death. Exhaustive pathological and biochemical investigations failed to find a cause. The scalp hair of both babies had an abnormal amino-acid composition, and presented an appearance that was unique on scanning electron microscopical examination; this fact and the clinical picture probably represents a new syndrome.  相似文献   
64.
In order to test the hypothesis that integrin and uteroglobin (UG) expression in cultured endometrial cells are affected by hormone treatment, Ishikawa-CH endometrial cancer cells were cultured and exposed to oestradiol or oestradiol and progesterone regimens and assayed using immunohistochemistry. We evaluated the intensity of immunohistochemical staining for the integrin monomers alpha(v) and beta1, the dimers alpha(v)beta3 and alpha(v)beta6, and for the secretory protein uteroglobin under various experimental conditions. Cells grown in control media stained positively for the integrin monomers alpha(v) and beta1, the dimer alpha(v)beta3, and for UG. Oestradiol and sequential oestradiol/progesterone reversibly suppressed staining for the dimer alpha(v)beta3. Hormone treatment had no effect on the staining of the beta1 and alpha(v) monomers or UG. The alpha(v)beta6 dimer antibody did not stain under any experimental treatment conditions. These data indicate that expression of the integrin complex alpha(v)beta3 is reversibly suppressed by oestradiol in Ishikawa cells and that these cells may be a good model for studying hormone-driven molecular changes in endometrium.   相似文献   
65.
对睾酮及表睾酮的三甲基硅烷化进行了详细考察,找到了较好的抗氧剂巯基乙醇,确定了较好的衍生化条件,衍生化产物单一。并采用GC—MS法测定了尿中睾酮与表睾酮的比值。实验条件为:以氦为载气,SE—54熔融石英柔性毛细管柱、程序升温进行样品分离,多离子检测(MID),监测m/z432的离子。该法专属、灵敏、快速。睾酮与表睾酮比值在1:1~10:1(睾酮为20ng/μl)与相应峰面积比呈线性关系(r=0.998),最低检测限为1ng,最低检测尿药浓度为8ng/ml。  相似文献   
66.
ABSTRACT: Two procedures were developed and evaluated that used either larger or smaller volumes for the detection of sperm antibodies in serum by means of an indirect immunobead test (IBT). The immunobeads, coated with rabbit antibody to each of the major human immunoglobulins (IgG, IgA, or IgM), were mixed with preparations of donor sperm, onto which antibody had been coated by passive transfer from various serum samples. The results of the IBT could be evaluated in various ways: (1) positive or negative; (2) if positive, whether binding is to the tail, the head, or the head and tail of the sperm cells; (3) if positive, whether binding is by IgG, IgA, or IgM. The diverse IBT results were obtained from a group of 50 serum samples; these sera were also tested by two sperm agglutination methods; the gelatin agglutination test (GAT) and the tube-slide agglutination test (TSAT). There was an excellent agreement between the IBT and the GAT; it was not as good between the IBT and the TSAT. However, considering both agglutination methods together, 90% of the IBT-positive sera were agglutination-positive. In terms of morphological sites, tail binding occurred in 27 of 31 sera, head binding in 12 of 31 sera, and head-tail binding in 15 of 31 sera. The number with tail binding was very close to the number that were GAT-positive (26). As for the immunoglobulins, the most frequent class was IgG. IgA was 83% as frequent and IgM was only 25% as frequent as IgG. In a larger group with only IgG and IgA, of 31 IBT-positive sera, 26 showed IgG and 23 showed IgA; 18 showed both. Hence, only eight showed IgG exclusively, and only five showed IgA exclusively. One final point is that several sera with GAT titers of only 4 were IBT-positive, adding strength to the concept that such a low GAT titer does have antibody significance.  相似文献   
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68.
薄层扫描法测定黄芪生脉颗粒中黄芪甲甙含量   总被引:5,自引:0,他引:5  
目的:制订黄芪生脉颗粒中黄芪甲甙含量测定方法。方法:双波长薄层扫描法,经乙酰洗涤、正丁醇提取和D101大乳吸附树脂柱层析法制备样品,以氯仿-甲醇-水(13:7:2)下层液为展开剂,检测波长为510nm,参比波长为700nm。结果:加标回收率平均为98.7%(RSD=2.0%,n=6),标准曲线r=0.9966,重复性RSD=1.4%(n=5),精密度RSD=2.0%(n=6)。结论:方法稳定、可靠  相似文献   
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