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791.
792.
The distribution of monoamine oxidase inhibitor-benzodiazepine receptor binding inhibitor, extractable into ethyl acetate at pH 1, was examined in a range of rat tissues. Great variation in the activity of both inhibitors was found in the different tissues, the highest being present in superior cervical ganglion, and lowest in adrenal gland. There was a highly significant correlation between the distribution of the two activities in different tissues, supporting the concept that they both derive from the same molecule (tribulin). The level of inhibitory activity in some of the tissues was such that variations might conceivably play a significant role in vivo. 相似文献
793.
目的:探讨窄带成像内镜(NBI)、染色内镜及常规内镜模式鉴别诊断非肿瘤性、肿瘤性结直肠增生性病变的应用价值。方法:选择2017年2月至2019年3月西安市中心医院消化科收治的结直肠增生性病变患者,均行NBI、染色内镜、常规内镜检查。比较三种模式图像清晰度以及鉴别诊断非肿瘤性、肿瘤性结直肠增生性病变的效能。结果:NBI、染色内镜模式图像质量评分分布优于常规内镜(P<0.05),NBI图像质量评分分布优于染色内镜模式(P<0.05)。以病理结果为准,常规内镜结直肠增生性病变检出率73.13%,NBI 91.04%,染色内镜96.26%,NBI、染色内镜结直肠增生性病变检出率高于常规内镜(P<0.05),NBI、染色内镜比较无统计学差异(P>0.05)。NBI模式下检测NBI分型与病理组织学结果一致性较好(kappa值=0.801,P<0.05)。NBI、染色内镜诊断肿瘤性结直肠增生性病变的灵敏度、特异度、阳性预测值、阴性预测值、准确度均明显高于常规内镜,染色内镜、NBI、常规内镜诊断肿瘤性结直肠增生性病变的曲线下面积(AUC)分别为0.844(95%CI:0.812~0.956)、0.921(95%CI:0.860~0.982)、0.750(95%CI:0.651~0.848)。结论:NBI、染色内镜在鉴别非肿瘤性和肿瘤性结直肠增生性病变方面效能相似,均优于常规内镜,NBI分型与病理组织学结果一致性高,更适合结直肠增生性病变的鉴别诊断。 相似文献
794.
T. A. Ryder M. Lynn MacKenzie Rachel Lewinsohn J. Pryse-Davies M. Sandler 《Histochemistry and cell biology》1980,67(2):199-204
Summary The enzymes monoamine oxidase A (MAO A), monoamine oxidase B (MAO B) and benzylamine oxidase (BzAO) have been localized histochemically in the human uterus during various phases of the menstrual cycle. The results show a large increase in MAO A activity in the endometrial gland cells in the secretory phase of the cycle. MAO B activity was found in both endometrium and myometrium but did not show a cyclical variation in activity. BzAO was localized primarily in the tunica media of the myometrial blood vessels. These observations have been supported by parallel biochemical assays.This research was supported by the Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CN Pq), Brazil and The Wellcome Trust, U.K., who defrayed the salary of Rachel Lewinsohn 相似文献
795.
It was the aim of the present study to investigate the significance of culture before and after freeze-thawing of isolated mouse pancreatic islets. To evaluate the impact of culture before freezing (5 degrees C/min; 2 M dimethyl sulfoxide), islets were frozen either directly after isolation or after 2, 4, or 7 days of culture in medium RPMI 1640. The culture period after thawing was 7 days. Islets immediately frozen exhibited virtually no (pro)insulin biosynthesis and also a severe inhibition of glucose-stimulated insulin release. The precultured (2-7 days), frozen islets synthesized and released insulin at rates comparable to those of nonfrozen, cultured islets. Studies of the effects of culture after freeze-thawing were performed after a 3-day culture period prior to freezing. The (pro)insulin biosynthetic rates did not differ between islets cultured for 0-7 days after thawing. There was an apparent increase of glucose-stimulated insulin release when the islets were cultured for more than 2 days after thawing. It may be that the decreased viability of islets frozen immediately after isolation was due to minor cell damage induced by the collagenase incubation. During culture the islets may recover and become more resistant to freeze-damage. The beneficial effect of culture after thawing may reflect the loss of damaged cells, which otherwise would influence the results of the viability tests. 相似文献