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991.
光镜和电镜观察慢性宫颈炎上皮不典型增生42例,宫颈癌21例,正常对照7例。上皮不典型增生之一是位于深部的储备细胞增生,细胞的核质比大,细胞器少,分化较低。鳞状上皮不典型增生细胞特点是核质比增大,核形不整,核膜内陷,细胞器增多,桥粒和张力原纤维减少。鳞癌细胞的核质比更大,核膜内褶深,细胞器更多,桥粒和张力原纤维很少或消失,分化低的癌细胞尤明显。粘液性腺癌腺上皮深部可见储备细胞转化的癌细胞。 相似文献
992.
C. Feretis D. Tabakopoulos P. Benakis M. Xenofontos B. Golematis 《Surgical endoscopy》1990,4(2):88-90
Summary This report describes the technique and results of endoscopic fistulotomy as a drainage procedure in cases of malignant obstruction of the biliary system from bulky and friable growths in the papilla of Vater. Fistulotomy, coupled with insertion of stents, was successful in seven of eight patients and was associated with relief of jaundice. It is suggested that the method be applied when conventional transpapillary insertion of stents is impossible either due to distortion of the papilla or bleeding of the growth on touch. 相似文献
993.
胚胎颅骨骨膜移植修复髋关节软骨大面积缺损 总被引:9,自引:3,他引:6
1990年5月~1994年4月,对42例(47个髋)关节软骨全厚缺损患者采用冷冻保存胚胎颅骨骨膜移植进行修复,其中14例股骨头骨质Ⅳ期坏死者,同时施行带旋髂深血管蒂髂骨植骨。对34例(38个髋)进行了2年~6年(平均40个月)随访。结果表明,按照吴之康髋关节人工置换术后疗效评定标准,优良25例,很好5例,好3例,尚可1例。认为,与自体移植物修复关节软骨大面积缺损相比,这种方法无附加损伤,具有移植材料、形态与股骨头相似等特点,是治疗髋关节软骨大面积缺损的一种有效方法。 相似文献
994.
Bernhard R. Slaap Irene M. van Vliet Herman G. M. Westenberg Johan A. Den Boer 《Psychopharmacology》1996,127(1-2):353-358
Little is known about biological predictors of treatment response in panic disorder (PD). In the present study heart rate,
blood pressure, plasma cortisol and plasma MHPG were investigated at baseline in a sample of 44 PD patients as possible predictors
for nonresponse to treatment. We used a strict definition of nonresponse to find patients who did not respond at all after
12 weeks of treatment with brofaromine or fluvoxamine. Patients were considered nonresponders when they fulfilled two criteria:
they did not show a 50% reduction of agoraphobic avoidance and they still experienced panic attacks at endpoint. The variables
that differed significantly between the groups were used to predict nonresponse to drug therapy. Using this strict definition
of nonresponse, 15 patients (32.6%) were considered nonresponders. These patients were characterised by a higher plasma MHPG
concentration and a higher heart rate at baseline. These variables were subsequently used to predict nonresponse. 相似文献
995.
以聚合酶链反应(PCR)法在mRNA水平检测T淋巴细胞受体α链可变区基因表达为例,介绍用~(32)P标记的人工合成寡核苷酸探针对PCR产物特异性作阳性证实的方法。该法以干琼脂糖凝胶作为支持物、相对较为简便和省财。用Ca探针以干凝胶作支持物的杂交结果,证实29个Vα基因的PCR扩增中物均为特异性的,放射自显影的带型与位置和溴乙锭染色所示完全吻合。 相似文献
996.
Reyna O. Calderon B. Maggio T. J. Neuberger G. H. Devries 《Journal of neuroscience research》1993,34(2):206-218
The axolemma membrane forms a stable and reproducible monomolecular layer at the air-aqueous interface. The major lipids and proteins are present in this monolayer in molar ratios similar to the original membrane. Acetylcholinesterase and Na-K-ATPase activities are preserved in the monolayer to levels of 64% and 25%, respectively. The total lipid fraction forms a homogeneously mixed phase. The presence of proteins in the monolayer introduces surface inhomogeneties. Among other features, this is revealed by the presence of two values of lateral pressure at which the monolayer shows partial or total collapse: a broad partial collapse at surface pressures between 13 to 30 mN/m and a sharp collapse point at 46 mN/m. The average molecular areas, the broad collapse point, and the variation of the surface potential per molecule suggest the relocation of protein components at surface pressures between 13 to 30 mN/m. The behavior is consistent with the extrusion and exposure of proteins toward the aqueous medium that depends on the lateral pressure. Schwann cells grown on coverslips coated with axolemma monolayers at 13 mN/m (beginning of the broad collapse) and 34 mN/m (above the broad collapse) recognize the difference in the surface organization of axolemma caused by the lateral pressure which affects their proliferation, morphology, and spatial pattern of organization. Our results show for the first time that response of Schwann cells depends on the intermolecular organization of the axolemma surface with which they interact. These results suggest that the local expression of putative surface molecules of axolemma that may mediate membrane recognition and the signalling of morphological and proliferative changes can be modulated by long range supramolecular properties. © 1993 Wiley-Liss, Inc. 相似文献
997.
The neuropeptide galanin (GAL) influences leaming and memory processes, perhaps by inhibiting cholinergic function. We recently reported that, in the rat, the nucleus of the horizontal limb of the diagonal band (HDB) exhibits the highest level of GAL mRNA coexpression by basal forebrain (BF) cholinergic neurons and, in the HDB, virtually all GAL mRNA-expressing neurons correspond to the cholinergic cell type. Since GAL gene expression is induced across puberty in many brain regions, we used in situ hybridization histochemistry and quantitative autoradiography to assess GAL gene expression across the rostro-caudal extent of the HDB in prepubertal and adult male rats and to determine whether GAL gene expression is also regulated during maturation in this BF region. Our results show that the number of GAL mRNA-expressing cells per section is significantly reduced in the HDB with adulthood. Post-hoc analysis indicated that these age-associated differences in the number of GAL mRNA-expressing cells per section could be ascribed to the rostral and central subregions of the HDB. Age-related differences in the labeling intensity of GAL mRNA-expressing neurons were also detected in the rostral and central subregions of the HDB. No age-associated differences in GAL gene expression were found in the caudal HDB subregion. These results suggest that: (1) in contrast to other brain regions, GAL gene expression in the cholinergic BF may be negatively regulated by factors concomitant with puberty; and (2) the inhibition of cholinergic function by cosecreted GAL may be enhanced prior to puberty within cholinergic neurons of the rostral and central aspects of the HDB. 相似文献
998.
T. Urano Y. Shibayama K. Fukunishi K. Nariyama N. Ohsawa 《Virchows Archiv : an international journal of pathology》1996,427(6):607-612
We examined the effect of interruption of pulmonary arterial flow and inadequate ventilation on the development of pulmonary infarction in rats. Pulmonary arterial flow was blocked by the injection of agar into the inferior vena cava and inadequate ventilation was produced by obstructing the left main bronchus with a polypropylene tip. Histological and angiographic examination of the lung demonstrated that: pulmonary artery embolism alone does not induce pulmonary infarction; obstruction of a bronchus does not induce significant changes, but that pulmonary infarction develops when pulmonary artery embolism and obstruction of a bronchus occur simultaneously. It has been thought that pulmonary infarction is caused by acute obstruction of a pulmonary artery, however, the alveolar walls are supplied with oxygen by both the pulmonary circulation and by ventilation. Interruption of pulmonary arterial flow alone is probably not sufficient to induce pulmonary infarction, which is probably caused by deficiency of oxygen supply to the alveolar walls by a synergy between interruption of pulmonary arterial flow and inadequate ventilation. 相似文献
999.
MRI诊断腰椎间盘术后粘连和突出复发 总被引:2,自引:0,他引:2
失败的下腰椎手术是个复杂的问题,由于其症状和体征不典型,单靠临床检查很难明确诊断,而脊髓造影和常规CT等检查也很难区别突出复发和硬膜外粘连。本文分析了32例再手术患者MRI图象,并与第二次手术所见对比,发现27例MRI诊断准确,3例假阳性,2例因信号缺失不能明确诊断。 相似文献
1000.