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161.
目的:探讨食管鳞状细胞癌组织中抑癌基因 DMBT1以及粘附分子 CD44v6的表达及与肿瘤生物学行为的关系。方法应用免疫组织化学方法检测70例食管鳞状细胞癌组织及23例切缘正常组织中 DMBT1、CD44v6的表达情况。结果 DMBT1、CD44v6在癌组织中的表达减弱或呈阴性。 DMBT1的表达与食管鳞状细胞癌组织的分化程度、淋巴结的转移有关( P <0.05),与癌组织的浸润深度无关( P >0.05)。 CD44v6的表达与食管鳞状细胞癌组织的淋巴结的转移有关( P <0.05),与癌组织的分化程度、浸润深度无关( P >0.05)。结论 DMBT1的表达减弱是食管鳞状细胞癌组织低分化和高度恶性的生物学标志,并与淋巴结的转移密切相关,CD44v6主要与食管鳞状细胞癌的发生与淋巴结的转移密切相关。 相似文献
162.
目的:探讨CD44v6蛋白表达与胰腺癌增殖及淋巴结转移的关系。方法:应用免疫组织化学(S-P)法检测38例胰腺癌组织标本中CD44v6和PCNA的表达。结果:CD44v6在胰腺癌中的阳性率为65%(25/38),与淋巴结转移呈非常显相关(P<0.01),与胰分化程度无关(P>0.05)。CD44v6阳性染色胰腺组织中PCNA标记率较阴性高(P<0.05)。结论:CD44v6在胰腺癌的增殖,转移过程中可能起重要作用,可作为胰腺癌预后预测的生物学指标之一。 相似文献
163.
Summary Using a case-control design we have studied whether antibodies to cow's milk proteins are risk determinants for childhood-onset Type 1 (insulin-dependent) diabetes mellitus independent of early exposure to cow's milk formula and islet cell antibodies. Sera from 116 recentonset diabetic children and 112 age- and sex- matched control children were analysed for cow's milk protein IgA, IgG and IgM antibodies, -lactoglobulin IgA and IgM antibodies and islet cell antibodies. The titres were compared to questionnaire data on duration of breast-feeding and introduction of formula feeding. Most antibody levels tended to be increased among diabetic compared to control children. This was statistically significant for cow's milk protein IgA antibodies (p <0.001) and -ltoglobulin IgA antibodies (p <0.01) as well as for islet cell antibody-positivity which was found among 92% of the diabetic and 3% of control children. The differences in cow's milk protein antibodies as well as -lactoglobulin antibodies were more pronounced among children with an early onset of Type 1 diabetes. Breast-feeding duration was significantly inversely related to the log of -Mactoglobulin IgG (r = –0.16, p = 0.04) and the log of cow's milk protein IgA antibodies (r = –0.17, p<0.001). A positive correlation was found between formula feeding and the logarithm of -lactoglobulin IgG antibodies (r = 0.22, p = 0.01) and the log of cow's milk protein IgA antibodies (r = 0.16, p = 0.04). In a multiple logistic regression analysis it was found that IgA antibodies to -lactoglobulin and cow's milk protein were significantly related to the risk of Type 1 diabetes independent of islet cell antibodies. When introducing formula feeding before the age of 4 months as a variable in the regression it was shown that islet cell antibodies and -lactoglobulin IgA antibodies were still significantly and independently related to an increased risk of diabetes whereas cow's milk protein IgA antibodies did not add further to the regression. It is concluded that -lactoglobulin IgA antibodies are significantly associated with an increased risk of diabetes at a young age independent of islet cell antibody-status and of an early weaning to cow's milk formula. In genetically susceptible children early exposure to -actoglobulin might be one trigger in the autoimmune process leading to development of Type 1 diabetes. 相似文献
164.
Miyajima E Shigemasa T Endo T Hishiki S Kawano Y 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》2000,14(1):61-66
The cardiovascular and sympatholytic effects of combination therapy with guanabenz were examined in 26 patients (48 ± 13 years old [mean ± SD]) with stage 2 and 3 hypertension. Included in the study were patients under treatment with conventional antihypertensive drugs whose systolic and diastolic blood pressure was above 140 and 90 mmHg, respectively. Blood pressure, heart rate, and sympathetic parameters such as plasma concentration of norepinephrine and muscle sympathetic nerve activity at rest as well as during ambulatory conditions, 24-hour urinary excretion of norepinephrine, and low frequency (LF: 0.04–0.15 Hz)/high frequency (HF: 0.15–0.4 Hz) power ratio as a marker of cardiac sympathetic activity during 24 hours were examined before and after guanabenz (4–8 mg/d) combination therapy with first-line antihypertensive drugs such as diuretics. Left ventricular mass index (LVMI) was also calculated by conventional echocardiography. After 32 weeks of guanabenz combination therapy, systolic and diastolic blood pressure, heart rate, plasma and urinary excretion of norepinephrine, muscle sympathetic nerve activity, and LF/HF power ratio were significantly decreased, while neither LF nor HF power was changed. LVMI was also significantly decreased (270 ± 81 vs. 236 ± 83 g/m2, p < 0.005). These results indicate that guanabenz combination therapy inhibits sympathetic nerve activity under resting conditions as well as during ambulatory conditions and may accelerate regression of left ventricular hypertrophy in patients with moderate to severe hypertension. 相似文献
165.
Expression of human chorionic gonadotropin, CD44v6 and CD44v4/5 in esophageal squamous cell carcinoma 总被引:5,自引:0,他引:5
Li DM Li SS Zhang YH Zhang HJ Gao DL Wang YX 《World journal of gastroenterology : WJG》2005,11(47):7401-7404
AIM: To study the relationship between the expression of human chorionic gonadotropin (HCG), CD44v6, CD44v4/5 and the infiltration, metastasis of esophageal squamous cell carcinoma. METHODS: By labeled streptavidin-biotin technique, the expressions of HCG, CD44v6, and CD44v4/5 in 42 patients with esophageal squamous cell carcinoma were examined. RESULTS: The positive rate of HCG expression in patients with lymph node metastasis was 85.71% (18/21), higher than that (57.14%, 12/21) in those without lymph node metastasis (P<0.05). The positive rate of CD44v6 expression was 71.43% (15/21) in lymph node metastasis group, and 38.09% (8/21) in non-metastasis group; there was a significant difference between the two groups (P<0.05). The positive rate of CD44v4/5 expression was 76.19% (16/21) in lymph node metastasis group, and 42.86% (9/21) in non-metastasis group; there was also a significant difference between them (P<0.05). From grade Ⅰ to grade Ⅲ in differentiation, the positive rate of HCG expression was 84.62% (11/13), 70.59% (12/17) and 58.33% (7/12), respectively; there was no significant difference among them (P<0.05). The positive rate of CD44v6 expression in grades Ⅰ-Ⅲ of cancer tissues was 76.92% (10/13), 52.94% (9/17), and 33.33% (4/12) respectively; there was no significant difference among them. The positive rate of CD44v4/5 expression in grades Ⅰ-Ⅲ of cancer tissues was 69.23% (9/13), 64.71% (11/17), and 41.67% (5/12) respectively; there was no significant difference among the three groups. There was no correlation between the positive rates of HCG and CD44v6, CD44v4/5 expression. Cancer cells in carcinomatous emboli and those infiltrating into vascular wall strongly expressed HCG, CD44v6, and CD44v4/5. CONCLUSION: Expression of HCG, CD44v6, and CD44v4/5 in esophageal squamous cell carcinoma is related to its infiltration and metastasis. HCG, CD44v6, and CD44v4/5 have different effects on the infiltration and metastasis of esophageal squamous cell carcinoma. 相似文献
166.
J. W. Smit N. R. Blom M. J. A. van Luyn F. Miedema C. J. M. Melief M. R. Halie 《Annals of hematology》1985,51(2):83-95
Summary We have studied the morphology and cytochemistry in relation to the immunological phenotyping and functional properties of T cells from eight patients with chronic T lymphocytosis. At the light microscopic level the morphology of the patients' lymphocytes was similar to that described for large granular lymphocytes. Ultrastructurally, a division into two groups could be made on differences in the amount of cytoplasm and the location and the more irregular form of the nuclei. The lymphocytes of one group (five patients) had in common the phenotype Fc+, T3+, T4–, T8+, Ia–, M1– and demonstrated (with the exception of one patient) the same functions: presence of K-cell activity, absence of NK, helper and suppressor cell activities. In the other group (three patients), the lymphocytes of one patient showed the same phenotype and functions as those indicated above. The other two patients both lacked the T8 antigen on their lymphocytes but were different with regard to other surface markers. In addition, their cells were functionally identical: both demonstrated NK- and K-cell activity. Thus in this group of eight patients with chronic T lymphocytosis, the immunological and functional subdivision paralleled in part a morphological division at the ultrastructural level. 相似文献
167.
Visiting Professor of Biochemistry Y. B. Lombardo W. T. Hron L. A. Menahan 《Diabetologia》1978,14(1):47-51
Summary Withdrawal of exogenous insulin and a subsequent fast (24 h) of alloxan diabetic rats stimulated rates of gluconeogenesis, ureogenesis, ketogenesis, and amino acid release by in situ perfused livers when compared to those from normal, fasted rats. The contribution of liver glycogen to the high rates of gluconeogenesis observed with the diabetic liver could be excluded. Perfusate lactate concentrations remained constant during the period when the elevated rate of gluconeogenesis was observed with diabetic liver. Addition of insulin as a bolus (750 mU) and continuous infusion (12.5 mU/min) to the perfusion medium of diabetic livers resulted in constant perfusate levels of glucose, urea and -amino nitrogen indicating a suppression of the catabolic processes present in the fasted, diabetic liver. The rate of ketogenesis was also slowed by insulin to about half the rate prior to addition of the hormone. These data indicate that insulin has an immediate anti-catabolic effect in the perfused, diabetic liver. 相似文献
168.
柴胡皂甙d对实验性膜性肾炎疗效及作用机理研究 总被引:14,自引:0,他引:14
本文观察了从中药柴胡中提取的单体成分柴在皂甙d(SSd)对被动物Heymann肾炎(PHN)的疗效。结果提示SSd的抗肾炎作用与其促进内源性糖皮质激素分泌、抑制PLA2活性、阻止IgG和C3在肾小球内沉积、提高SOD活性及改善异常的脂质代谢等作用密切相关。 相似文献
169.
Edward F. Plow 《Annals of hematology》1986,53(1):1-9
Summary Polymorphonuclear leukocytes accumulate within blood clots and may contribute to fibrinolysis. The primary fibrinolytic enzymes of neutrophils are cathepsin G and elastase. Fibrin can be exposed to these granular enzymes as a result of cell lysis, phagocytosis of fibrin, or secretion of the enzymes from the cells. Neutrophil secretion occurs in association with blood coagulation and is dependent upon a plasma factor(s) and calcium. After secretion, the enzymes can degrade fibirn within a plasma environment. This is demonstrated by the inhibition of fibrinolysis by specific inhibitors of elastase and the augmentation of fibrinolysis by neutralization of the primary plasma inhibitor of elastase, 1-proteinase inhibitor. A radioimmunoassay which discriminates elastase from plasmic degradation products of fibrinogen has been developed. In this assay, elastase elicited degradation products of fibrin(ogen) were detected in certain pathophysiologic plasma samples. Taken together, these findings indicate a role for leukocyte proteases in physiological fibrinolysis.Abbreviations PMN
polymorphonuclear leukocytes
- PK
prekallikrein
- FDP
fibrin(ogen) degradation products
This work was supported by HL 17 964 from the National Heart, Lung and Blood Institute 相似文献
170.
The aim of this preliminary study was to evaluate insulin resistance and secretion using homeostasis model assessment (HOMA) in patients with systemic lupus erythematosus (SLE). The fasting glucose and insulin concentrations, HOMA insulin resistance (IR), HOMA -cell, antidouble-stranded DNA antibodies (anti-dsDNA), C3, C4, and SLE disease activity index (SLEDAI) were determined in a total of 58 female SLE patients. All patients were classified into subgroups according to the presence of anticardiolipin antibodies (aCL+ vs. aCL-) and SLEDAI scores (SLEDAI <3 vs. SLEDAI >3). Results showed that SLE patients with and without aCL had significantly higher fasting insulin levels, HOMA IR, and HOMA -cells than controls. Similar results were also found in SLE patients with different disease activities. Pearsons correlation analysis showed that there was a highly significant correlation of HOMA IR with fasting insulin concentration in the SLE patients and SLE subgroups overall. However, HOMA -cells were positively correlated with HOMA IR and fasting insulin level, but negatively correlated with fasting glucose concentration in SLE patients overall. In conclusion, SLE patients, regardless of the presence of aCL and different disease activities, had a higher risk of insulin resistance and abnormal insulin secretion than age-matched healthy controls, based on fasting insulin concentration, HOMA IR, and HOMA -cells.Abbreviations HOMA Homeostasis model assessment - IGT Impaired glucose tolerance - IR Insulin resistance - NGT Normal glucose tolerance - SLE Systemic lupus erythematosus - SLEDAI SLE disease activity index 相似文献