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排序方式: 共有464条查询结果,搜索用时 15 毫秒
81.
Rainer Porschen Susanne Classen Yvonne Kahle Franz Borchard 《International journal of cancer. Journal international du cancer》1993,54(2):189-193
The association between the expression of the epidermal-growth-factor receptor (EGFR) and tumor proliferation was studied in 69 resected human adenocarcinomas of the colon. EGFR was detected immunohistochemically using the monoclonal antibody (MAb) EGFRI. Tumor-cell proliferation was assessed with the MAb Ki-67 directed against a proliferation-associated nuclear antigen expressed only in proliferating cells. The percentage of Ki-67-positive tumor cells (Ki-67 index) was evaluated by the point-counting method. Forty-seven carcinomas contained detectable EGFR immunoreactivity. Statistical analysis failed to reveal correlations between the EGFR status and T, N and M stages or tumor differentiation. The mean Ki-67 index did not differ between EGFR-positive and -negative carcinomas. Seven tumors contained clearly distinguishable areas with different EGFR staining intensity. In these tumors with a locally heterogeneous EGFR expression, tumor proliferation also did not correlate with EGFR immunoreactivity. These in situ observations suggest that EGFR expression may not play an important role in the growth regulation of human colonic carcinomas. 相似文献
82.
83.
Thompson FE Kipnis V Subar AF Krebs-Smith SM Kahle LL Midthune D Potischman N Schatzkin A 《The American journal of clinical nutrition》2000,71(6):1503-1510
BACKGROUND: Measurement of fruit and vegetable intake is important in the surveillance of populations and in epidemiologic studies that examine the relations between diet and disease. Some situations require the use of brief dietary assessment tools. OBJECTIVE: Our objective was to evaluate the performance of 2 brief dietary assessment instruments, a 7-item standard screener and a new 16-item screener, and a complete food-frequency questionnaire (FFQ) in measuring total fruit and vegetable consumption. DESIGN: About 800 men and women from the National Institutes of Health-AARP Diet and Health Study completed an FFQ, 1 of the 2 screeners, and two 24-h dietary recalls. Fruit and vegetable intakes as measured by each screener and the FFQ were compared with estimated true usual intake by using a measurement-error model. RESULTS: Median daily servings of fruit and vegetables were underestimated by both screeners. The estimated agreement between true intake and the screener was higher for the new screener than for the standard screener and was higher for women than for men. The estimated agreement between true intake and the FFQ was higher than that for both screeners. Attenuation coefficients for the FFQ and screeners were comparable. CONCLUSIONS: For estimating median intakes of fruit and vegetables and the prevalence of recommended intakes being met, the use of screeners without appropriate adjustment is suboptimal. For estimating relative risks in the relations between fruit and vegetable intake and disease, screeners and this FFQ are similar in performance. 相似文献
84.
Dixon LB Subar AF Wideroff L Thompson FE Kahle LL Potischman N 《The Journal of nutrition》2006,136(12):3054-3061
To improve the measurement of usual dietary intake, the National Cancer Institute developed a cognitively based Diet History Questionnaire (DHQ), which has been validated against four 24-h dietary recalls (4 24-HR) for energy, macronutrients, and several vitamins and minerals. This analysis used data from The Eating at America's Table Study (EATS) to determine the validity of estimates for carotenoids and tocopherols from the DHQ. Over the course of a year, 163 participants provided 1 or 2 blood samples and completed the DHQ and 4 24-HR. For both the DHQ and the 4 24-HR, crude correlations between serum and diet were modest to strong for the provitamin A carotenoids (alpha-carotene, beta-carotene, beta-cryptoxanthin), low to modest for lycopene, and very low for lutein. The individual dietary tocopherols were weakly correlated with the serum tocopherols, but vitamin E from food and dietary supplements was strongly and positively correlated with serum alpha-tocopherol and strongly and inversely correlated with serum gamma-tocopherol for both instruments. Adjustment for energy, BMI, smoking status, serum total cholesterol, and serum triacylglycerol did not appreciably change the correlations. Using the method of triads, validity coefficients for the DHQ were comparable to the 4 24-HR and were especially strong for alpha-carotene, beta-cryptoxanthin, lutein + zeaxanthin, and total vitamin E in men and gamma-tocopherol and total vitamin E in women. In this study, there was no advantage of 2 blood samples over 1, suggesting reasonably stable ranking of individuals for these biomarkers, which is important for large epidemiologic studies that typically obtain only 1 blood sample for biomarker status. 相似文献
85.
Subramaniam Ramachandran Aiyalu Rajasekaran KT Manisenthilkumar 《Asian Pacific Journal of Tropical Biomedicine》2012,2(4):262-268
Objective
To investigate the hypoglycemic, hypolipidemic and antioxidant activities of aqueous extract of Terminalia paniculata bark (AETPB) in streptozotocin (STZ)-induced diabetic rats.Methods
Acute toxicity was studied in rats after the oral administration of AETPB to determine the dose to assess hypoglycemic activity. In rats, diabetes was induced by injection of STZ (60 mg/kg, i.p.) and diabetes was confirmed 72 h after induction, and then allowed for 14 days to stabilize blood glucose level. In diabetic rats, AETPB was orally given for 28 days and its effect on blood glucose and body weight was determined on a weekly basis. At the end of the experimental day, fasting blood sample was collected to estimate the haemoglobin (Hb), glycosylated haemoglobin (HbA1c), serum creatinine, urea, serum glutamate-pyruvate transaminase (SGPT), serum glutamate-oxaloacetate transaminase (SGOT) and insulin levels. The liver and kidney were collected to determine antioxidants levels in diabetic rats.Results
Oral administration of AETPB did not exhibit toxicity and death at a dose of 2 000 mg/kg. AETPB treated diabetic rats significantly (P<0.001, P<0.01 and P<0.05) reduced elevated blood glucose, HbA1c, creatinine, urea, SGPT and SGOT levels when compared with diabetic control rats. The body weight, Hb, insulin and total protein levels were significantly (P<0.001, P<0.01 and P<0.05) increased in diabetic rats treated with AETPB compared to diabetic control rats. In diabetic rats, AETPB treatment significantly reversed abnormal status of antioxidants and lipid profile levels towards near normal levels compared to diabetic control rats.Conclusions
Present study results confirm that AETPB possesses significant hypoglycemic, hypolipidemic and antioxidant activities in diabetic condition. 相似文献86.
Gerd Bobe Leah B Sansbury Paul S Albert Amanda J Cross Lisa Kahle Jason Ashby Martha L Slattery Bette Caan Electra Paskett Frank Iber James Walter Kikendall Peter Lance Cassandra Daston James R Marshall Arthur Schatzkin Elaine Lanza 《Cancer epidemiology, biomarkers & prevention》2008,17(6):1344-1353
Two recent case-control studies suggested that some flavonoid subgroups may play a role in preventing colorectal cancer. Previous prospective cohort studies generally reported no association; however, only a small subset of flavonoids was evaluated and partial flavonoid databases were used. We used the newly constructed U.S. Department of Agriculture flavonoid database to examine the association between consumption of total flavonoids, 6 flavonoid subgroups, and 29 individual flavonoids with adenomatous polyp recurrence in the Polyp Prevention Trial. The Polyp Prevention Trial was a randomized dietary intervention trial, which examined the effectiveness of a low-fat, high-fiber, high-fruit, and high-vegetable diet on adenoma recurrence. Intakes of flavonoids were estimated from a food frequency questionnaire. Multivariate logistic regression models (adjusted for age, body mass index, sex, regular non-steroidal anti-inflammatory use, and dietary fiber intake) were used to estimate odds ratios and 95% confidence intervals for both any and advanced adenoma recurrence within quartiles of energy-adjusted flavonoid intake (baseline, during the trial, and change during the trial). Total flavonoid intake was not associated with any or advanced adenoma recurrence. However, high intake of flavonols, which are at greater concentrations in beans, onions, apples, and tea, was associated with decreased risk of advanced adenoma recurrence (4th versus 1st quartile during the trial; odds ratio, 0.24; 95% confidence interval, 0.11, 0.53; P(trend) = 0.0006). Similar inverse associations were observed to a smaller extent for isoflavonoids, the flavonol kaempferol, and the isoflavonoids genistein and formononetin. Our data suggest that a flavonol-rich diet may decrease the risk of advanced adenoma recurrence. 相似文献
87.
Wir berichten über den seltenen Fall einer isolierten Zungenbeinfraktur bei einem Jugendlichen durch ein direktes Trauma.
Er?rtert werden Unfallmechanismus sowie Diagnostik und Therapie. 相似文献
88.
We present two cases of buttock claudication caused by severe stenosis of the internal iliac artery which disappeared totally after percutaneous transluminal angioplasty (PTA). Isolated stenoses of internal iliac arteries are rare. It is often difficult to distinguish between vascular buttock claudication and neurological or orthopaedic symptoms. Conventional or MR-angiography is necessary to secure the diagnosis. PTA of internal iliac artery stenosis is the adequate treatment. 相似文献
89.
Molecular pathogenesis of inherited hypertension with hyperkalemia: the Na-Cl cotransporter is inhibited by wild-type but not mutant WNK4 总被引:16,自引:0,他引:16 下载免费PDF全文
Wilson FH Kahle KT Sabath E Lalioti MD Rapson AK Hoover RS Hebert SC Gamba G Lifton RP 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(2):680-684
Mutations in the serine-threonine kinases WNK1 and WNK4 [with no lysine (K) at a key catalytic residue] cause pseudohypoaldosteronism type II (PHAII), a Mendelian disease featuring hypertension, hyperkalemia, hyperchloremia, and metabolic acidosis. Both kinases are expressed in the distal nephron, although the regulators and targets of WNK signaling cascades are unknown. The Cl(-) dependence of PHAII phenotypes, their sensitivity to thiazide diuretics, and the observation that they constitute a "mirror image" of the phenotypes resulting from loss of function mutations in the thiazide-sensitive Na-Cl cotransporter (NCCT) suggest that PHAII may result from increased NCCT activity due to altered WNK signaling. To address this possibility, we measured NCCT-mediated Na(+) influx and membrane expression in the presence of wild-type and mutant WNK4 by heterologous expression in Xenopus oocytes. Wild-type WNK4 inhibits NCCT-mediated Na-influx by reducing membrane expression of the cotransporter ((22)Na-influx reduced 50%, P < 1 x 10(-9), surface expression reduced 75%, P < 1 x 10(-14) in the presence of WNK4). This inhibition depends on WNK4 kinase activity, because missense mutations that abrogate kinase function prevent this effect. PHAII-causing missense mutations, which are remote from the kinase domain, also prevent inhibition of NCCT activity, providing insight into the pathophysiology of the disorder. The specificity of this effect is indicated by the finding that WNK4 and the carboxyl terminus of NCCT coimmunoprecipitate when expressed in HEK 293T cells. Together, these findings demonstrate that WNK4 negatively regulates surface expression of NCCT and implicate loss of this regulation in the molecular pathogenesis of an inherited form of hypertension. 相似文献
90.
KL Goh PL Cheah YM Tan M Rosmawati KT Ong YL Lo SC Chin 《Journal of digestive diseases》2001,2(3):137-141
OBJECTIVE : To determine and compare the efficacy of 5‐day t.d.s and 7‐day b.d. treatment regimens comprising lansoprazole, clarithromycin and amoxicillin in the eradication of Helicobacter pylori. METHODS : Patients with unequivocal evidence of H. pylori infection based on histology and rapid urease tests of both antrum and corpus biopsies were recruited for the study. The study was a randomized, investigator‐blind, comparative study. Patients received either 500 mg clarithromycin t.d.s. and 500 mg amoxicillin t.d.s. for 5 days (LAC5) or 500 mg clarithromycin b.d. and 500 mg amoxicillin b.d. for 7 days (LAC7) together with 30 mg lansoprazole (both groups) daily for either 5 or 7 days, depending on the treatment group. Patients were assessed for the successful eradication of H. pylori, defined as the absence of bacteria based on histology and urease tests on both antral and corporeal biopsies, carried out at least 4 weeks after completion of the therapy. RESULTS : One hundred and eight patients were recruited for the study. In the LAC5 treatment group, four patients failed to return for follow up and in the LAC7 group, two failed to return for follow up and two were not compliant with medications. Eradication rates based on an intention‐to‐treat analysis were: 46/54 for LAC5 (85.2%; 95% CI = 72.9–93.4) and 47/54 for LAC7 (87.0%; 95% CI = 75.1–94.6). Based on a per protocol analysis, the rates were: 46/50 for LAC5 (92.0%; 95% CI = 80.8–97.8) and 47/50 for LAC7 (94.0%; 95% CI = 83.5–98.7). Both treatment regimens were convenient for patients and except for two patients in the LAC7 group, all patients reported taking 100% of all prescribed medications. The side‐effects encountered were uniformly mild and no patient discontinued treatment because of intolerance to medications. The most common side‐effects were altered taste (LAC5 64.7%; LAC7 78.8%). Diarrhea, nausea and anorexia were reported in a minority of patients. CONCLUSIONS : Both the LAC5 t.d.s. and the LAC7 b.d. treatment regimens were well tolerated by patients and were highly effective in the eradication of H. pylori. 相似文献