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171.
The present study was designed to determine whether tumor induction by 3-methylcholanthrene (MC), a carcinogenic hydrocarbon, can be inhibited by oral administration of Lactobacillus casei strain Shirota (LC). C3H/HeN mice were divided into four groups and assigned to the following treatments: treated with MC and given control or LC-containing diet; treated with vehicle only and given control or LC-containing diet. MC (1 mg) was injected intradermally at 7 weeks of age and the tumor incidence was monitored; LC was mixed into a diet at a concentration of 0.05% (w/w) and the diet was fed from the day of MC injection throughout the study. Spleen cells were analyzed for the immune parameters at 12 and 16 weeks after the MC injection. Oral feeding of mice with LC reduced tumor incidence (P < 0.05). MC treatment lowered the in vitro response to concanavalin A (Con A) of spleen cells, the secretion of interleukin-2 in spleen cell culture after stimulation of the cells with Con A and the proportions of CD3+, CD4+ and CD8+ splenic cells. However, the analysis of the spleen cells obtained from the mice treated with MC and given the LC-containing diet revealed that these disrupted host immune parameters were maintained at the level of normal controls. These results suggest that oral feeding of mice with LC inhibits MC-induced tumorigenesis by modulating the disrupted host immune responses during MC carcinogenesis. Received: 14 April 1999  相似文献   
172.
Binge eating disorder (BED), characterized by ingestion of very large meals without purging afterwards, is found in a subset of obese individuals. We showed previously that stomach capacity is greater in obese than in lean subjects, and in this study, we investigated capacity in obese individuals with BED. We also determined ad-libitum intake of a test meal until extremely full. Furthermore, we measured various appetitive hormones (insulin, leptin, glucagon, CCK, ghrelin) and glucose before a fixed meal and for 120 min afterwards. An acetaminophen tracer was used to assess gastric emptying rate. We compared three groups of overweight women: 11 BED, 13 BE (subthreshold BED), and 13 non-binge-eating normals. The BED individuals had the largest stomach capacity as assessed by either maximum volume tolerated (P=.05) or by gastric compliance to pressure (P=.02) using an intragastric balloon. Although test meal intake did not differ between groups, it correlated (P=.03) with gastric capacity. The BED group showed a tendency (P=.06) to have greater area under the curve (AUC) and had higher values at 5 and 60 min (P<.05) for insulin compared to normals. Moreover, the BED subjects had lower ghrelin baselines premeal, and lower AUC for ghrelin, which then declined less postmeal than for the normals (P<.05). None of the other blood values differed, including glucose, leptin glucagon, and CCK, as well as acetaminophen, reflecting gastric emptying. The lower ghrelin in BED, although contrary to what was expected, is consistent with lower ghrelin in obesity, and suggests down-regulation of ghrelin by overeating. The lack of differences in CCK is consistent with the lack of differences in gastric emptying rate, given that CCK is released when nutrients reach the intestine. The results show that BED subjects have a large gastric capacity as well as abnormalities in meal-related ghrelin and insulin patterns that may be factors in binge eating.  相似文献   
173.
Previous studies using conventional hetero- or isoantisera have indicated the involvement of class II (Ia) molecules in presentation of soluble by monocytes to inducer T lymphocytes, stimulation of inducer T cells in MLR, and recognition of Ia-bearing targets cells by cytotoxic T lymphocytes (CTL). The experience in using monoclonal anti-Ia reagents capable of blocking these phenomena in the human system is limited. Recently, however, we have characterized a lytic IgG2a monoclonal antibody, 9–49, that binds to functionally significant class II molecules. This antibody blocks (in the absence of complement): (1) specific binding of peripheral blood lymphocytes (PBL) to antigen-pulsed monocyte monolayers, (2) proliferation of PBL in response to soluble antigen (tetanus toxoid or mumps) or cell surface class II antigen stimulation in allogeneic or autologus MLR, (3) proliferation of cloned T4+ (inducer) lymphocyte cell lines to class II antigens, (4) generation of cytotoxic lymphocytes during allogenic MLR, and (5) recognition (and killing) of class II-bearing target cells by T4+ CTL clones. Proliferation and CTL activity of a T8+ clone is unaffected by the 9–49 antibody. These results indicate the usefulness of this monoclonal reagent in studies evaluating the functional role of Ia molecules in immune recognition phenomena.  相似文献   
174.
A 73-year-old Japanese man with a history of partial gastrectomy due to gastric cancer 4 years previously was admitted because of intermittent fever. The patient developed abdominal pain, erythema, and myalgia in addition to the fever during the final clinical course, and died of acute heart failure. Autopsy disclosed atrophy of the left lobe of the liver and acute myocardial infarction. Neither metastasis nor recurrence of the cancer was observed. Small and medium-sized arteries of the visceral organs showed various stages of necrotizing vasculitis with narrowing of the lumina. The vasculitis was most prominent in the left lobe of the liver and in the heart. Narrowing of the portal vein due to portal tract inflammation in addition to vasculitis of the hepatic arteries may have induced ischemia and infarction, which had resulted in atrophy of the left hepatic lobe. Acta Pathol Jpn 42: 662–666, 1992.  相似文献   
175.
Cadherin-17 (CDH17), also called liver–intestine cadherin, is a structurally unique member of the cadherin superfamily. Our serial analysis of gene expression demonstrated that CDH17 was one of the most up-regulated genes in advanced gastric carcinomas. CDH17 expression is known to be regulated by Cdx2. In the present study, we examined the expression of CDH17 in primary gastric carcinoma tissues by immunohistochemistry, and analyzed the correlation of CDH17 expression with clinicopathological characteristics and patients prognosis. CDH17 expression was detected in 63/94 (67%) of gastric adenocarcinomas in addition to intestinal metaplasia. The expression of CDH17 tended to be associated with intestinal type carcinoma, and carcinomas with CDH17 expression was significantly more frequent in advanced stage cases (80%) than in early stage (53%). The prognosis of patients with positive CDH17 expression was significantly poorer than that of the negative cases (P=0.0314). However, multivariate analysis revealed that CDH17 was not an independent prognostic factor. Six of seven cases that showed positive expression of Cdx2 simultaneously expressed CDH17 protein. These results suggested that the expression of CDH17 was characteristic of the advanced gastric carcinoma that is associated with poor prognosis.  相似文献   
176.
老年与中青年癌症病人心理健康状况比较研究   总被引:2,自引:0,他引:2  
癌症是一种心身疾病 ,心理社会因素在癌症的发生、发展及预后中均起着重要作用。反过来 ,癌症对病人来说又是一种恶性刺激 ,会给病人带来沉重的心理负担 ,影响疾病的康复和生活质量 ,并可加速癌症的恶性进展 ,造成不良后果。有研究表明 ,老年与中青年癌症病人因社会地位、社会经验及社会责任的不同而各具特点[1] 。了解不同年龄癌症病人的心理状况 ,并采取相应的处理策略 ,对癌症的治疗和康复具有积极作用。我们对 1999年 7月~ 2 0 0 0年 8月收治的 12 6例老年和 96例中青年癌症病人的心理健康状况进行了对比分析 ,结果总结如下。1 材料和…  相似文献   
177.
Summary The ionic composition of the internal environment was altered in rabbits by means of gastric washing, combined with intramuscular administration of 3-Beta-aminoethylpyrazole. The effects of this treatment on cortical spreading depression (SD) were studied. C1- and Na+ concentrations decreased significantly in serum and in cerebrospinal fluid after the treatment. This made the animals much more susceptible to SD, as established by the high incidence of spontaneous SD, increased SD velocity of propagation and facilitated its interhemispheric transfer. An intensification of the epileptiform activity associated with SD was also observed. Intravenous replacement of NaCl abolished the above effects on SD. When the intravenous replacement was done with Na-Isethionate, those effects were enhanced. It is concluded that chloride deficiency was the main factor responsible for the observed facilitating effects.This work was supported by grants from the BNDE (FUNTEC-74 e 143), CNPq and CAPES  相似文献   
178.
The effect of membrane stretch on voltage-activated Ba2+ current (I Ba) was studied in antral circular myocytes of guinea-pig using the whole- cell patch-clamp technique. The changes in cell volume were elicited by superfusing the myocytes with anisosmotic solutions. Hyposmotic superfusate (202 mosmol/l) induced cell swelling and increased peak values of I Ba at 0 mV (from −406.6 ± 45.5 pA to −547.5 ± 65.6 pA, mean ± SEM, n = 8) and hyperosmotic superfusate (350 mosmol/l) induced cell shrinkage and decreased peak values of I Ba at 0 mV (to −269.5 ± 39.1 pA, n = 8). Such changes were reversible and the extent of change was dependent on the osmolarity of superfusate. The values of normalized I Ba at 0 mV were 1.43 ± 0.04, 1.30 ± 0.06, 1.23 ± 0.04, 1.19 ± 0.04, 1 and 0.68 ± 0.06 at 202, 220, 245, 267, 290 and 350 mosmol/l, respectively (n = 8). I Ba was almost completely blocked by nicardipine (5 μM) under hyposmotic conditions. The values of steady-state half-inactivation voltage (−37.7 ± 3.3 and −36.5 ± 2.6 mV, under control and hyposmotic conditions, respectively) or the half-activation voltage (−13.6 ± 2.3 and −13.9 ± 1.9 mV) of I Ba were not significantly changed (P > 0.05, n = 6). Cell membrane capacitance was slightly increased from 50.00 ± 2.86 pF to 50.22 ± 2.82 pF by a hyposmotic superfusate (P < 0.05, n = 6). It is suggested that cell swelling increases voltage-operated L-type calcium channel current and that such a property is related to the response of gastric smooth muscle to mechanical stimuli. Received: 14 November 1995/Received after revision and accepted: 8 January 1996  相似文献   
179.
Renal carcinoma developed in two or more members of nine families. Multiple generations were affected in five kindreds, and siblings in four. The median age at cancer diagnosis was a decade earlier than usual, and individual patients had bilateral or multifocal lesions; these are features of hereditary forms of diverse cancers. No patient had von Hippel-Lindau disease or other predisposing genetic syndromes. Karyotypes of the peripheral blood of nine persons showed no instance of a 3;8 chromosome translocation as recently reported in association with renal carcinoma in ten members of one family. The findings show that familial renal cancer is more common than previously reported in the literature.  相似文献   
180.
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