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901.
Transitional mucosa adjacent to colorectal cancers is essentially characterized by an excess of sialomucins at the expense of the normally predominant sulphomucins in epithelial cells lining the intestinal crypts which presents the early stage of oncogenic transformation of colorectal epithelium. The presence or absence of sialomucins at the resection margins was studied histochemically using the high iron diamine-alcian blue(HID-AB) stain in 64 rectal cancer patients in Dukes' B stage who underwent curative anterior resection. The correlation was revealed between the presence of sialomucins at the resection margins and subsequent development of local tumour recurrence. Fourteen of 27 patients (51.9%) with sialomucins predominant pattern at either resection margin developed local recurrence compared with 4 of 37 patients (10.8%) with sulphomucins predominant pattern (P less than 0.001). It is suggested that determination of the transitional mucosa around anastomosis in patients treated for the rectal carcinoma by anterior resection appears to identify those with a higher risk of local recurrence. 相似文献
902.
乳癌根治术是治疗乳腺癌的主要手段,但并发臂丛神经损伤的报道却很少,总结从1989年10月~1991年2月华山医院诊治的9例,3例门诊治疗,6例住院治疗。其中5例行神经松解后,皮瓣或肌皮瓣转移覆盖神经瘢痕区。随访到8例,疼痛改善3例,感觉和运动改善2例,疗效不理想,认为寻找预防措施是减少乳癌根治术后臂丛损伤的根本办法。 相似文献
903.
促甲状腺素释放激素拮抗β-内啡肽对心血管的抑制作用 总被引:2,自引:0,他引:2
本研究用兔侧脑室给药观察了促甲状腺素释放激素(TRH)对β-内啡肽心血管抑制作用的影响。结果表示,β-内啡肽(10μg,icv)能显著抑制兔心血管功能,表现为血压下降,心机收缩力指标如左室收缩压(LVSP),心室内压最大上升和下降速率(±dp/dtmax),心肌纤维收缩速度(Vce40,Vpm)和心肌收缩向量环面积(Lp)明显降低。β-内啡肽的这一作用可被TRH(50μg,icv)取消,阿片受体拮抗剂纳洛酮(NAL,50μg,icv)也可拮抗β-内啡肽的心血管抑制作用,表明,TRH与内源性阿片肽系统有密切关系,结合以前的实验结果提示TRH拮抗β-内啡肽的心血管抑制作用有可能是作用在阿片受体上的。 相似文献
904.
上皮样肉瘤的病理学研究 总被引:4,自引:0,他引:4
Thirteen cases of epithelioid sarcoma were studied by light microscopy (LM), electron microscopy and immunohistochemical technique. LM revealed a nodular pattern of the tumor cells, which consisted of various degrees of a typical epithelioid cells and plump spindle-shaped cells. Irregular necrosis was seen in the centre of some nodules. Ultrastructurally the tumor cells exhibited abundant intermediate filaments, desmosome-like cell junctions and small intercellular spaces surrounded by microvilli. Immunohistochemically, there was positivity for vimentin and keratin. The author discussed diagnosis, differential diagnosis and histogenesis of epithelioid sarcoma. 相似文献
905.
江苏省婴儿死亡报告工作中,出现漏报率为17.87%,婴儿死亡漏报率为25.61%,农村出生漏报率和婴儿死亡漏报率均高于城市。婴儿死亡漏报中年龄越小,漏报越多;男女性别之间无显著性差异。城乡婴儿死亡漏报的主要死因是肺炎、意外死亡、新生儿窒息和先天畸形。本文还分析了造成漏报的主要原因,并提出了防止漏报的对策和干预措施。 相似文献
906.
Antibodies to glutamic acid decarboxylase discriminate major types of diabetes mellitus. 总被引:13,自引:0,他引:13
Insulin-dependent diabetes mellitus (IDDM) is marked by circulating antibodies to a 64,000-M(r) islet cell antigen identified as glutamic acid decarboxylase (GAD). We describe a radioimmunoprecipitation assay with GAD isolated from pig brain. The sera tested were from 80 patients with IDDM including 26 with disease of recent onset and 54 with disease of longer duration (3-42 yr), 20 with non-insulin-dependent diabetes mellitus (NIDDM), and 55 nondiabetic subjects. Conventional assays for islet cell cytoplasmic antibodies were performed concurrently. The level of antibody in serum was expressed in units based on percentage reactivity of a standard reference serum. The frequency of antibody to GAD in IDDM was 69% in short-duration cases and 59% in long-duration cases. The latter was substantially higher than the frequency of islet cell cytoplasmic antibody. Antibodies to GAD were elevated (means +/- 3 SD) in 5% NIDDM cases and in none of the nondiabetic subjects. A simple laboratory test with a defined autoantigen has substantial implications for population screening and early diagnosis of IDDM and for better understanding of its pathogenesis. 相似文献
907.
采用大鼠30%Ⅲ度烫伤模型,应用光镜、电镜、3β-羟甾脱氢酶(3β-HSD)组织化学染色及其相对活性的测定和血清睾酮及黄体生成素(LH)浓度的检测,分不同时相对严重烫伤后30天内大鼠睾丸间质细胞的改变进行了动态观察。结果表明,烫伤后睾丸间质细胞有不同程度的变性、坏死;间质细胞内3β-HSD活性迅速降低,伤后30天仍保持较低水平;血清睾酮水平迅速下降,并持续维持较低水平,伤后30天仍不回升,而血清LH浓度无明显改变。提示烫伤后血清睾酮下降的机理可能与睾丸间质细胞的受损及糖皮质激素升高有关。 相似文献
908.
Alveolar hydatid disease of the liver: computed tomography and transabdominal ultrasound with histopathological correlation. 总被引:5,自引:0,他引:5
K Choji N Fujita M Chen A S Spiers Y Morita M Shinohara T Nojima G Irie 《Clinical radiology》1992,46(2):97-103
The appearances of alveolar hydatid disease of the liver (AHDL) on computed tomography (CT) and ultrasound (US) were retrospectively compared with histopathological appearances in 67 patients with 100 separate lesions. The radiological features were correlated directly with the pathological specimens obtained from each patient. We conclude that the CT appearances are more specific, but that US has a role to play in mass screening in endemic areas, and intraoperatively. 相似文献
909.
用YAG、CO_2激光按不同功率照射家兔眼,观察对角膜、虹膜、晶状体的损伤和修复过程,探索两种激光对角膜的最小损伤和使其穿孔的有效功率。结果发现:YAG激光用230~250mW(1~2秒)时,可使角膜上皮呈灰白色混浊,1~2W(5~6秒)时角膜穿孔;CO_2激光用340~380mW(0.2~2秒)时,同样使角膜上皮灰白色混浊,1.3~1.4W(1秒)时角膜穿孔,在功率、照射时间、光斑相同的条件下,CO_2激光对角膜损伤重,YAG激光则对虹膜、晶状体损伤重。 相似文献
910.