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41.
应用银染技术,对24例结肠腺癌Ⅱ级不典型增生,30例绒毛状腺瘤,14例绒毛状腺瘤Ⅲ级不典型增生和29例高分化管状腺癌进行银染核仁形成区嗜银蛋白(Ag-NORs)定量研究,观察Ag-NORs数量、形态、大小和分布在结肠肿瘤交界性病变中的表达.提示Ag-NORs四项指标定量研究对结肠脉瘤,特别是Ⅲ级不典型增生与绒毛状腺瘤之结肠癌前病变有较好的监测作用.  相似文献   
42.
This retrospective study included 2532 wounded, of whom 354 (14 per cent) were treated in surgical intensive care units. In 32 patients, 1.3 per cent of all admissions, upper gastrointestinal bleeding was detected. It occurred on average 8.9 days (3–21 days) after the wounding or surgical procedure in severely injured patients and those treated in intensive care units, respectively (32 of 354 patients, 9.0 per cent). All patients received different analgesic drugs and 17 of a group that presented with bleeding were given psychotropic agents as well. The majority of patients (96.3 per cent) were administered H2-receptor antagonists as prophylaxis against stress ulcer disease. There was a statistically significant difference between these patients treated with H2-receptor antagonists and those on no prophylactic therapy. No statistically significant difference was found between cimetidine and ranitidine in terms of their efficacy. Endoscopic examination revealed multiple bleeding gastric and duodenal erosions. The lesions were most commonly located in the corpus of the stomach. In the majority of patients (56.25 per cent), the haemorrhage stopped spontaneously and rebleeding presented in four of 32 (12.5 per cent) patients. Of 354 patients treated in intensive care units, five (1.4 per cent) had to be operated on because of bleeding arrest. Despite all therapeutic and surgical procedures undertaken, five of 32 (15.6 per cent) patients died.  相似文献   
43.
带宫内避孕环系常用之节育措施,不正常子宫出血系常见之并发症。本文旨在研究发生出血的机制,提出改进意见,以利于带环妇女的健康,提高带环率。本文对12例带不锈钢环后月经过多妇女的子宫内膜进行超微结构研究,与6例带环而月经正常的妇女对比,结合基础体温、血雌孕激素测定等资料加以讨论。研究结果表明:(1)带环不影响卵巢功能。(2)环周围区与远离区内膜发育的不同步可能是出血过多的重要原因。(3)选择大小适宜的环(宁小勿大)既提高避孕效果又避免出血过多。  相似文献   
44.
O Steward 《Hippocampus》1992,2(3):247-268
This study evaluates whether three forms of sprouting occur in the hippocampus of the cat following unilateral entorhinal cortex (EC) lesions: (1) sprouting of projections from the EC contralateral to the lesion; (2) sprouting of the commissural/associational system; and (3) sprouting of mossy fibers. Tract tracing techniques were used to define the normal organization of the entorhinal cortical projection system, the commissural/associational (C/A) systems, and the mossy fiber projections in normal cats. The same techniques were then used to evaluate whether there were changes in these projections in animals with long-standing unilateral EC lesions. The projections from the entorhinal cortex were evaluated autoradiographically following injections of 3H proline into the entorhinal area. The projections of the C/A system were traced using the Fink-Heimer technique after lesions of the hippocampal commissures, and by using autoradiographic techniques after injections of 3H proline into the hippocampus. The distribution of mossy fibers was evaluated using the Timm's stain. The results reveal that unilateral lesions of the EC in cats lead to the same sorts of sprouting that have been described in rats. There is: (1) an increase in the density of the crossed projection from the surviving EC to the contralateral dentate gyrus that had been deprived of its normal EC inputs; (2) an expansion of the terminal field of the C/A projection system into portions of the molecular layer of the dentate gyrus normally occupied by EC projections; and (3) an increase in supragranular mossy fibers in some animals. The mossy fiber sprouting was especially prominent when the lesions encroached upon the hippocampus. The studies also reveal additional details about the normal organization of hippocampal pathways in cats. The most important points are: (1) there is a crossed projection from the entorhinal cortex to the contralateral dentate gyrus; and (2) there is a complex laminar organization of the commissural and associational terminal fields in the molecular layer of the dentate gyrus that appears to be related to the point of origin of the projections along the septotemporal axis of the hippocampus. This heretofore unrecognized aspect of the laminar organization of C/A terminations has important implications for the temporal competition hypothesis, which has been advanced to account for the development of these afferent systems.  相似文献   
45.
Donor bone grafts are an important aspect of orthopaedic surgery. The use of plain film as a pathological screening tool before donor bone dispatch has revealed “lytic” lesions in proximal humeri. Donor demographics did not support the diagnosis of myeloma and subsequent computed tomography (CT) scans of these bones identified the lesions as air, not pathology. In total, 27 long bones were scanned and 100% (27/27 cases) exhibited air within the trabecular bone. Three distinct patterns were found: ovoid, linear/branching, and broad channel. A longitudinal course of CT scans was performed to identify at which stage air appeared within the bone. Pre-retrieval, preprocessing, and postprocessing scans revealed that air originated between the retrieval and preprocessing stages of donor bone preparation. There may be multiple aetiology of this phenomenon, including bone retrieval and natural decomposition.  相似文献   
46.
BACKGROUND: Traditionally patients with a high rectosigmoid carcinoma and a synchronous large distal rectal adenoma would be treated by low anterior resection with associated loss of rectal function. METHOD: Four patients with a carcinoma of the upper rectum or distal sigmoid colon and a synchronous distal rectal adenoma were treated by high anterior resection followed by staged Transanal Endoscopic Microsurgery (TEM) thus conserving the distal rectum. Preoperative and postoperative rectal function was assessed using the St. Mark's incontinence score. RESULTS: The proximal carcinomas and distal adenomas were 12-18 cms and 0.5-9 cms respectively from the dentate line. The mean surface area of the distal adenomas was 9.7 cms2. There were no deaths or major complications. There were no recurrences after a mean follow-up of 31.5 months. Rectal function was unchanged in three patients with a minor increase in the score in one. CONCLUSION: Staged high anterior resection and 'rEM offers effective treatment of synchronous rectosigmoid carcinoma and distal rectal adenoma with preservation of rectal function.  相似文献   
47.
Binswanger’s disease is pathologically characterized by a combination of diffuse cerebrovascular white matter lesions and lacunar infarcts in the basal ganglia and white matter. Although a blood-brain barrier (BBB) dysfunction has been implicated in the pathogenesis of these white matter (WM) lesions, few authors have addressed this problem. In the present study, we describe BBB dysfunction and its regional differences in the brains of Binswanger’s disease patients. Twelve brains from Binswanger’s disease patients (group III) were examined and compared with those from five patients with non-neurological disease (group I) and five cortical infarct patients without significant WM lesions (group II). Immunohistochemistry was performed for glial fibrillary acidic protein and vimentin as astroglial cell markers, and for immunoglobulins, complements and fibrinogen as extravasated serum protein markers. The grading scores for IgG extravasation were significantly higher in group III as compared to group I, in both the periventricular WM and the subcortical WM (P < 0.01). In group III, the scores in the periventricular WM and subcortical WM were significantly higher than in the subcortical U fibers and cerebral cortex (P < 0.01 for the periventricular WM; P < 0.001 for the subcortical WM), respectively. Clasmatodendritic astroglia, which had swollen cell bodies and large cytoplasmic vacuoles with disintegrated processes, incorporated the serum components IgG, IgM, C3d, C1q and fibrinogen, both in the periventricular WM and subcortical WM in 5 out of 12 (42%) Binswanger’s disease brains. These results indicate that WM lesions in Binswanger’s disease are accompanied by BBB dysfunction, although it remains uncertain whether BBB dysfunction is secondary to either chronic cerebral ischemia or arterial hypertension. Received: 25 April 1997 / Revised, accepted: 21 July 1997  相似文献   
48.
门脉高压性胃粘膜损害出血的细胞动力学   总被引:2,自引:0,他引:2  
武永忠  何泽生 《医学争鸣》1997,18(3):266-269
探讨肝硬变门脉高压性胃粘膜损害出血的机制。应用放射自显影技术观察肝硬变门脉高压大鼠在饥饿12-36h后的胃粘膜上皮细胞标记指数变化及其与胃粘膜出血的关系。结果:1;LC-PHT鼠平均LI氏于对照,出血灶局部2LI低于周围相对正常粘膜。2.随饥饿持续时间延长LI呈降低趋势,而出血率及严重程度呈增加趋势,尤以严重程度增加为著。3.当出血为0-3级时与LI呈显著负相关;为3-4级时两者间呈正相关但未达显  相似文献   
49.
Fatigue is a frequent and disabling phenomenon among patients with multiple sclerosis (MS). Daytime sleepiness is a typical symptom of the sleep apnoea/hypopnoea syndrome due to nocturnal hypoxia and recurrent arousals causing sleep fragmentation. Since MS plaques are often found in the midbrain, brain stem and upper cervical cord on magnetic resonance imaging (MRI) we hypothesized that fatigue in MS patients might be caused by a central respiratory dysfunction. We investigated 10 patients with definite MS by oligography, two questionnaires assessing fatigue (Fatigue Severity Scale, FSS) and daytime sleepiness (Epworth Sleepiness Scale, ESS), MRI and pulmonary function tests. A total of six patients had either an elevated FSS and/or an elevated ESS. None of the six patients with an elevated FSS and/or ESS has an apnoea index > 5/hour. CT90 was normal in nine patients. We conclude that fatigue and daytime sleepiness in MS cannot be explained by nocturnal apnoeas or oxygen desaturations. The Fatigue Severity Scale should be integrated to the extended Barthel index, which is a new instrument for disability assessment in MS patients.  相似文献   
50.
Placental growth hormone is the product of the GH-V gene specifically expressed in the syncytiotrophoblast layer of the human placenta. Placental growth hormone differs from pituitary growth hormone by 13 amino acids. It has high somatogenic and low lactogenic activities. Assays by specific monoclonal antibodies reveal that in the maternal circulation from 15 to 20 weeks up to term placental growth hormone gradually replaces pituitary growth hormone, which becomes undetectable. It is secreted by the placenta in a nonpulsatile manner. This continuous secretion appears to have important implications for physiologic adjustment to gestation and especially in the control of maternal insulin-like growth factor-I levels. Placental growth hormone secretion is inhibited by glucose in vitro and in vivo and is significantly decreased in the maternal circulation in pregnancies with intrauterine growth restriction. Placental growth hormone does not appear to have a direct effect on fetal growth because this hormone is not detectable in the fetal circulation. However, the physiologic role might also include a direct influence on placental development through an autocrine or paracrine mechanism, as suggested by the presence of specific growth hormone receptors in this tissue.(Am J Obstet Gynecol 1997;177:1526-34.)  相似文献   
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