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排序方式: 共有6476条查询结果,搜索用时 15 毫秒
81.
G. Pals A. W. Eriksson J. C. Pronk R. R. Frants E. C. Klinkenberg-Knol A. Bosma B. D. Westerveld R. T. Taggart I. M. Samloff S. G. M. Meuwissen 《Clinical genetics》1988,34(2):90-97
The pepsinogen A (PGA) isozymogens in the gastric mucosa and Barrett epithelium of a female patient with Barrett esophagus were studied on different occasions during a 3-year period by electrophoretic analysis of in vivo steady-state pepsinogen in biopsies by activity staining in combination with variant specific monoclonal antibodies and of de novo synthesized pepsinogen by autoradiography. In Barrett epithelium only one (Pg3) or two (Pg3 and Pg5) primary PGA gene products were detected, whereas in gastric mucosal biopsies three (Pg3, Pg4 and Pg5) primary gene products were demonstrated on all occasions. These differences strongly suggest differential expression/activation of individual gene numbers in the PGA gene cluster in Barrett esophagus and are in line with the preneoplastic nature of this condition. The mechanism behind this deregulation is currently under investigation by cell biology and molecular genetic techniques. 相似文献
82.
Koji Sekikawa Jan W. Arends Kees Verstijnen Joop ten Kate Bert Schutte Fred T. Bosnian 《Virchows Archiv : an international journal of pathology》1990,416(5):393-396
Summary We used the nude mouse tumour xenograft model to study the pathogenesis of mucosa alterations in the large bowel surrounding a carcinoma. In mouse colonic mucosa overlying HT-29 colonic carcinoma xenografts in the caecum, the crypts were elongated in comparison with those in distant mucosa and also frequently showed a shift towards sialomucin production. These features, which are comparable with socalled transitional mucosa (TM) in man, were absent in control animals inoculated with Indian Ink instead of HT-29 cells. Although the localization of the proliferative cell compartment in mouse colonic mucosa overlying HT-29 xenografts appeared to be confined to the lower half of the crypt as in normal mucosa, the relative length of the DNA synthesizing cell compartment along the crypts was slightly elongated. These data strongly suggest that TM should be regarded as a secondary phenomenon rather than a premalignant change in large intestinal epithelium and that higher proliferative activity of epithelial cells contributes little to the elongation of crypts in TM. 相似文献
83.
AIMS: To validate histological criteria for the grading of epithelial hyperplastic laryngeal lesions (EHHL) (dysplastic laryngeal lesions), we used a system that had been devised and tested in Ljubljana, Slovenia over many years and was felt to be more appropriate to laryngeal pathology than is the commonly-used model of intraepithelial neoplasia in the cervix. METHODS AND RESULTS: Vocal cord biopsies of 45 patients with a broad spectrum of EHLL were reviewed. Detailed histological criteria were formulated for each of the four grades of EHLL in the Ljubljana classification, comprising simple hyperplasia (benign spinous layer augmentation), abnormal hyperplasia (benign basal and parabasal layer augmentation), atypical hyperplasia (risky for malignancy) and carcinoma in situ (actually malignant, but without invasion). CONCLUSIONS: Using these criteria a high degree of concordance of histological diagnoses of grading levels for the Ljubljana classification was achieved between the pathologists of the Working Group. The system was found to be more precise for routine diagnostic work than the others in vogue. The different grades of the Ljubljana classification correspond to significantly different levels yielded in each grade by the semiobjective methods of quantitative morphometry and immunohistochemistry. 相似文献
84.
Hiromitsu Watanabe Taro Okamoto Masahiro Matsuda Tadateru Takahashi Peter Osa Ogundigie Akihiro Ito 《Pathology international》1993,43(9):456-463
The influence of sex hormones on induction of intestinal rnetaplasia was examined in 5 week old Crj: CD (SD) rats of both sexes. At the age of 4 weeks, the animals were gonadectornized and given testosterone or dimethyl estradiol (DES). One week after operation, they were irradiated with two 10 Gy doses of X-rays to the gastric region at a 3 day interval for a total of 20 Gy. At the termination of the experiment, 6 months after the X-irradiation, the incidence of intestinal metaplasia with alkaline phosphatase (ALP) positive foci in males was significantly higher than in females, in orchidectomized males or orchidectomized plus DES treated rats (P <0.01). On the other hand, the incidence of intestinal metaplasia with ALPpositive foci in normal females appeared lower than in ovariectomized females (P < 0.01), and was increased in rats by treatment with testosterone or decreased by DES. Numbers of foci of intestinal metaplasias with Paneth cells and total numbers appeared to increase in males treated with DES. The results suggested a promoting role for testosterone in the development of ALP positive lesions and indicated considerable heterogeneity between intestinal metaplasia subtypes. 相似文献
85.
R. S. Johansson M. Trulsson K. Å. Olsson K. -G. Westberg 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1988,72(1):204-208
Summary The feasibility of adopting the microneurography technique (Vallbo and Hagbarth 1968) as a tool to investigate the mechanoreceptive innervation of peri- and intra-oral tissues was explored. Multi-unit activity and impulses in single nerve fibers were recorded from the infraorbital nerve in healthy volunteers. The innervation territories of individual nerve fascicles were mapped. These varied considerably but most fascicle fields comprised the corner of the mouth. Twenty-four single mechanoreceptive units were recorded. Eighteen innervated the skin of the face, and six innervated the mucous membranes of the lips or cheeks. A majority of the mechanoreceptive afferent units were slowly adapting with small and well defined receptive fields. It is suggested that the various slowly adapting responses may originate from two different types of afferent units. No afferents showed response properties similar to typical Pacinian-corpuscle afferents. 相似文献
86.
成年大鼠嗅球和鼻腔嗅粘膜成鞘细胞的分离、培养与鉴定 总被引:3,自引:2,他引:3
目的 在嗅球成鞘细胞 (OECs)移植到脊髓可有助于损伤神经纤维再生的基础上 ,分别对嗅球和嗅粘膜的OECs进行培养 ,探索自体嗅粘膜作为OECs供体的可能性。 方法 根据OECs、成纤维细胞和星形胶质细胞贴壁时间的不同 ,采用差时贴壁方法分离出OECs,培养 14div后进行NGFRp75和GDNF的免疫细胞化学染色。 结果 按形态学和免疫组织化学特性 ,培养的嗅球和嗅粘膜OECs可分为 3类 :双极细胞、三级细胞和扁圆细胞 ,其中以双极细胞最多。嗅粘膜的双极成鞘细胞的突起更加细长。 结论 差时贴壁细胞分离法是一种简单、经济、实用的成鞘细胞分离方法。鼻腔嗅粘膜OECs的形态学和免疫细胞化学特性与嗅球OECs基本相同 ,本实验为临床开展自体嗅粘膜OECs修复脊髓损伤的研究提供参考 相似文献
87.
目的:探讨急性胰腺炎并发十二指肠粘膜损伤与一氧化氮合酶(nitric oxide synthase,NOS)改变的关系。方法:用胰管结扎及加压注射法建立大白兔急性胰腺炎模型,采用黄递酶组织化学染色法观察与比较两组动物胰腺及十二指肠组中NOS的变化。结果:经Winslow法测定血清淀粉酶分析及组织学检查,急性胰腺炎模型建立;经NADPH-d染色表明:实验组NOS染色强度明显高于对照组。结论:一氧化氮(nitric cxide,NO)在急性胰腺炎并发十二指肠粘膜损伤的病变过程中起重要的介导作用。 相似文献
88.
Nepomnyashchikh LM Aidagulova SV Ivaninskii OI Kunin IS 《Bulletin of experimental biology and medicine》2002,134(3):301-306
A new form of morphogenesis of pathological process, cystopathy, was distinguished on the basis endoscopy data and morphofunctional analysis of the urinary bladder in chronic cystitis. Cystopathy is characterized by predominance of diffuse degeneration and atrophy of the urothelium, stromal sclerosis, absence of inflammatory cell infiltration, and inhibition of biosynthetic reactions in urothelial cells (compared to chronic cystitis). Cystopathy results from regeneratory and plastic failure. Instability of the bladder epithelium can be a morphological marker of oncological risk. 相似文献
89.
90.
胃粘膜相关淋巴组织型淋巴瘤形态学研究 总被引:12,自引:5,他引:12
目的:研究胃粘膜相关淋巴细胞(MALT)型淋巴瘤及共与胃粘膜套细胞淋巴瘤和滤泡性淋巴瘤的鉴别诊断。方法:应用HE染色和免疫组化ABC法检测胃MALT型淋巴瘤,内镜作幽门螺杆菌培养基尿素试验检测HP感染。结果:31例胃MALT型淋巴瘤中低度恶性27例,高度恶性4例。细胞类型以CCL型最常见。免疫表型以IgM为主,缺乏IgD,31例中28例有HP感染(占90.52%),结论:(1)低恶MALT型淋巴瘤 相似文献