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991.
目的:探讨胃粘膜肠化生细胞DNA含量与增殖状态分型、硫酸化粘液分泌状况之间的关系。方法:采用DNA图像分析技术测定394例胃粘膜活检及外科手术标本中细胞DNA含量,并对187例伴肠化生慢性萎缩性胃炎作免疫组化与粘液组化套染,进行肠化生增殖状态分型。结论:胃粘膜出现肠化生和异型增生、癌变时,出现异倍体细胞且百分率显著增高(P<0.01);高增殖型肠化生中异倍体细胞的百分率显著高于中、低增殖型肠化生(P<0.01)。结论:提示高增殖型肠化生与胃癌的发生密切相关。 相似文献
992.
Alanine aminopeptidase (EC 3.4.11.2), leucine aminopeptidase (EC 3.4.11.1), proline dipeptidase (EC 3.4.13.9), and prolyl dipeptidase (EC 3.4.13.8) have been investigated in small intestinal mucosa homogenates of normal children and children suffering from different degrees of villous damage. The activities of proline dipeptidase and prolyl dipeptidase could be shown to be significantly decreased in cases of subtotal and total villous atrophy, whereas the activities of alanine aminopeptidase and leucine aminopeptidase were not influenced. The results are discussed in view of the subcellular distribution of these enzymes. 相似文献
993.
N. O. BERG S. BORULF I. JAKOBSSON T. LINDBERG 《Acta paediatrica (Oslo, Norway : 1992)》1978,67(4):403-411
ABSTRACT. 180 children (mean age 20 months) suspected of malabsorption because of failure to thrive, abnormal stools more than 3 weeks, vomiting, an/or abdominal distension were investigated with peroral small intestinal biopsy at duodeno-jejunal flexure (172 children) and/or duodenal intubation for analysis of trypsin and amylase activity in duodenal juice before and after a test meal of water (76 children). Results of xylose tolerance test, lactose tolerance test, faecal fat, B-folate, S-iron, and S-albumin were related to morphology of mucosa. A normal finding of one of these tests means in 15–26% a normal mucosa (diagnostic sensitivity). An abnormal finding means in 40–85% a severely damaged mucosa and in 85–100% a slightly, moderately, or severely damaged mucosa (diagnostic specificity). Combinations of these tests increase the diagnostic sensitivity 10–15%. Faecal chymotrypsin seems to be a reliable screening test for exocrine pancreatic function. Border values or low values indicate a direct evaluation of exocrine pancreatic function. The simple test meal (water) method with determination of trypsin in duodenal juice gives, from a practical point of view, good information of the exocrine pancreatic function.
The following plan of investigation is proposed: Step 1. careful clinical history and examination; Step 2. analysis of faeces for Giardia lamblia, entero-pathogenic microorganisms, and chymotrypsin, sweat test; Step 3. peroral small intestinal biopsy and/or duodenal juice analysis, and finally—if steps 2 and 3 give normal results; Step 4. re-evaluation of dietary history and tests to detect any food intolerance (e.g. carbohydrate). 相似文献
The following plan of investigation is proposed: Step 1. careful clinical history and examination; Step 2. analysis of faeces for Giardia lamblia, entero-pathogenic microorganisms, and chymotrypsin, sweat test; Step 3. peroral small intestinal biopsy and/or duodenal juice analysis, and finally—if steps 2 and 3 give normal results; Step 4. re-evaluation of dietary history and tests to detect any food intolerance (e.g. carbohydrate). 相似文献
994.
大肠癌伴肠梗阻的诊治(附120例分析) 总被引:3,自引:0,他引:3
高章元 《第二军医大学学报》1999,20(11):881-882
目的:探讨大肠癌合并肠梗阻外科诊治的有关问题。顺顾性分析了10年(1989年4月至1999年5月)120例梗阻性大肠癌的外科处理。结果:根治怀切除72例(切除率60%),捷径手术9例,单纯肠造口39例,术后并发症38例,术后并发症38例(31.7%)。结论:大肠癌合并肠梗阻一经确诊,应积极争取手术治疗,术式选择应根据患者具休病情,尤其对左半结肠癌梗阻,尽可能以一期手术切除为宜。 相似文献
995.
原位杂交法检测表皮生长因子受体基因mRNA在大肠癌和大肠息肉中的表达 总被引:1,自引:0,他引:1
目的]检测表皮生长因子受体基因mRNA在大肠癌和大肠息肉中的表达.[方法]应用原位杂交法.[结果]表皮生长因子受体基因mRNA阳性表达率在大肠癌中为67%(27/40),在移行区为40%(16/40),在大肠息肉中为36%(8/22),与正常区的5%(2/40)相比较有非常显著性差异;但表皮生长因子受体基因mRNA阳性表达与大肠癌的浸润深度、分化程度和有无淋巴结转移无关.表皮生长因子受体基因mRNA阳性表达部位在细胞浆内.[结论]表皮生长因子受体的过度表达与大肠癌和大肠息肉的生物学行为有一定正相关 相似文献
996.
997.
《International reviews of immunology》2013,32(1):29-41
Increasing evidence points to multiple pathways of T lymphocyte development. The well characterized thymus-dependent pathway gives rise to T cells bearing TCRαβ heterodimers and either CD4 or CD8αβ co-receptors. T cells of this lineage populate peripheral lymphoid compartments including lymph nodes, spleen, skin, and Peyer's patches. By comparison, factors which govern extrathymic T cell development are poorly understood. A variety of experiments have shown that intestinal intraepithelial lymphocytes (IELs) develop outside of the thymic environment, e.g., in the gut of nude, SCID, and β2m-/- mutant mice, and after transplanting bone marrow or fetal liver cells into irradiated thymectomized adult mice. This review focuses on the role of the CD3-ζ subunit in the development of both thymically and extrathymically derived T cells as determined by gene-targeting experiments in mice. Data from these and other T cell-related mutations continue to define crucial stages in thymocyte differentiation. Most interestingly, CD3-ζ mutant mice contain a unique population of intestinal IELs that develops independently of thymic selective processes and expresses a novel TCR/CD3 complex. 相似文献
998.
999.
The purpose of the study was to determine the morphology and distribution of vasoactive intestinal polypeptide- and peptide histidine isoleucine-immunoreactive (VIP- and PHI-ir) neurons and innervation patterns in the main and accessory olfactory bulb, anterior olfactory nucleus, and piriform cortex of the adult cat. In these centers, VIP- and PHI-immunoreactive material are present in the same neuronal types, respectively, therefore summarized as VIP/PHI-ir neurons. In the main olfactory bulb, the majority of VIP/PHI-ir neurons are localized in the external plexiform layer. These neurons give rise to two or more locally branching axons. They form boutons on mitral and external tufted cell bodies. According to the morphology and location, we have classified these neurons as Van Gehuchten cells. Some VIP/PHI-ir neurons are present in the glomerular layer. They have small somata and give rise to dendrites branching exclusively into glomeruli. We have classified these neurons as periglomerular cells. In the granule cell layer, neurons with long apical dendrites and one locally projecting axon are present. In the accessory olfactory bulb, VIP/PHI-ir neurons are localized in the mixed external/mitral/internal plexiform layer. They represent Van Gehuchten cells. In the anterior olfactory nucleus and piriform cortex, VIP/PHI-ir bipolar basket neurons are present. They are localized mainly in layers II/III. These neurons are characterized by a bipolar dendritic pattern and by locally projecting axons forming basket terminals on large immunonegative cell somata. Because of their common morphological features, we summarize them as the retrobulbar VIP/PHI-ir interneuron population. The PHI-ir neurons display the same morphology as the VIP-ir cells. However, they are significantly lower in number with a ratio of VIP-ir to PHI-ir cells about 2:1 in the main and accessory olfactory bulb and in the anterior olfactory nucleus. By contrast, in the piriform cortex the ratio is about 1:1. 相似文献
1000.
BACKGROUND: The use of fecal alpha1-antitrypsin in the monitoring of intestinal inflammation in infants with atopic eczema and food allergy was evaluated. METHODS: The study material comprised 26 atopic infants with confirmed food allergy. Fecal samples were collected before an elimination diet and 3 months later for the determination of alpha1-antitrypsin. RESULTS: Nine (35%) of the 26 patients demonstrated an increased fecal concentration of alpha1-antitrypsin (median 3 mg/g; range 2.8-6.4 mg/g). In all nine patients (100%) the oral cow's milk challenge was positive as opposed to only six (35%) in those with normal alpha1-antitrypsin concentration (P = 0.0024). No further connections between alpha1-antitrypsin and other food allergies were detected. As a result of an adequate elimination diet, the fecal concentration of alpha1-antitrypsin was normalized in seven patients, with a favourable clinical response in atopic eczema in six and no improvement in one patient. CONCLUSIONS: Our results indicate that serial determinations of fecal alpha1-antitrypsin provide a useful non-invasive tool for the detection and follow-up of intestinal inflammation in a certain group of atopic infants with cow's milk allergy and severe inflammation of the gut. 相似文献