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961.
962.
The aim of the present study was to determine the effects of conjugated equine estrogens (CEE) and selective estrogen receptor modulators (SERM) (tamoxifen [TAM] and raloxifene [RAL]) on the expression of steroid receptors—estrogen receptor (ER) and progesterone receptor (PR)—in intact rat uterus, mammary gland, and liver. A total of 24 female rats weighing 250 to 300 g were randomized into 4 groups. Groups 1, 2, 3, and 4 were respectively given conjugated equine estrogen, tamoxifen, raloxifene, and vehicle for a 28-day period. ER and PR expression was detected in tissues of the uterus, mammary gland, and liver. Uterine wet weight and serum estradiol levels were established for all groups. No statistical difference was observed between groups in the ER expression of mammary gland and liver and in the PR expression of uterus, mammary gland, and liver, but differences were noted in serum estradiol levels and uterine ER expression. Serum estradiol levels were lower in the TAM-treated group; differences between the TAM-treated group and the other groups were statistically important (P > .05). Uterine ER expression was greater in the CEE-treated group; differences between the CEE-treated group and theTAM and RAL-treated groups were statistically important (P > .05). CEE or SERM versus vehicle treatment in controls did not seem to result in statistically important differences in ER and PR expression in intact rat uterus, mammary gland, and liver. Only ER expression in the uterus was found to be greater in the CEE-treated group than in SERM-treated groups.  相似文献   
963.
BACKGROUND/AIMS: Lymphoid follicles and the satellite lesions (intestinal metaplasia, atrophy and dysplasia) are known as precursor lesions of mucosa associated lymphoid tissue lymphomas in gastritis. Little is known about their prevalence in different distributions and types of Helicobacter pylori-associated gastritis. The aim of the study was to estimate the topographic prevalence of these lesions in gastritis related with Helicobacter pylori and to associate them with the density of bacteria. METHODOLOGY: Histology for the type of gastritis and for lymphoid follicles and Helicobacter pylori density were studied in antrum and/or corpus biopsies taken from 107 consecutive patients with clinical diagnosis of peptic ulcer. RESULTS: Lymphoid follicles, panmucosal and superficial gastritis were seen in 31 (31.9%), 84 (86.6%) and 13 (13.4%) out of 97 antrum biopsies, respectively. In the corresponding 28 corpus biopsies, these lesions were seen in 8 (28%), 15 (54%), 13 (46%), respectively. Lymphoid follicles were found more in panmucosal than superficial gastritis in the antrum, however in the same ratios in the corpus. In association with lymphoid follicles, Helicobacterpylori was positive in 7 (87%) of 8 corpus biopsies and in all (100%) of 31 antrum biopsies. No relation was observed between lymphoid follicles and Helicobacter pylori density. CONCLUSIONS: Examination of antrum biopsies rather than corpus biopsies would be sufficient to screen precarcinogenic lymphoid follicles in Helicobacterpylori associated gastritis.  相似文献   
964.
Seasonal variation of P-wave dispersion in healthy subjects   总被引:2,自引:0,他引:2  
We studied the seasonal variability of P dispersion in 523 healthy male patients, aged 22 +/- 4 years (range, 20-26). Four seasonal 12-lead resting electrocardiograms were recorded at 2 mV/cm standardization and at 50 mm/s paper speed at intervals of three months. Electrocardiograms were recorded between the hours 10 to 12 AM. The difference between the maximum P-wave duration and minimum P-wave duration was calculated and defined as "P dispersion." There was a significant seasonal variation in the maximum P-wave duration (P = .001) and P dispersion (P = .001), with the longest maximum P-wave duration (121 +/- 16 ms) and P dispersion (41 +/- 7 ms) observed in winter and the shortest maximum P-wave duration (106 +/- 15 ms) and P dispersion (24 +/- 8 ms) observed in summer. The minimum P-wave duration did not show any significant seasonal variation. In conclusion, there exists a significant seasonal variation in the maximum P-wave duration and P dispersion in healthy patients. Seasonal variation of P dispersion resulted from the significant variation of maximum P-wave duration.  相似文献   
965.
PURPOSE: Irritable bowel syndrome is generally diagnosed according to the symptoms of the patient, and gluten enteropathy can also be presented with similar symptoms (diarrhea and/or constipation) of irritable bowel syndrome. Aimed to assess the association and the frequency of gluten enteropathy in a group of Turkish patients diagnosed as irritable bowel syndrome. RESULTS: Found anti-gliadin IgA positivity only in four patients among patients with irritable bowel syndrome. However, none of these four patients had anti-endomycium positivity or any histopathological findings specific for gluten enteropathy. All these four patients had normal histology in their small bowel biopsies. CONCLUSION: Irritable bowel syndrome is a common problem in the population, but gluten enteropathy is not associated with the vast majority of subjects with irritable bowel syndrome as expected. The need for screening gluten enteropathy among these patients is still unclear, and screening with serology only without small bowel biopsy may lead to false positive results.  相似文献   
966.
The shape of the left ventricle is an important echocardiographic feature of left ventricular dysfunction. Progression of the mitral regurgitation and consequent left ventricular remodeling is unpredictable in heart failure. Elongation index is an index of left ventricular sphericity. The surface area of the elongated ventricle is larger than that of a spherical one. The objective of this study was to assess the relation between elongation index and the degree of mitral regurgitation along with noninvasive indices of left ventricular function. Thirty-two patients (21 male, 11 female, mean age: 57 +/- 6 yrs) with congestive heart failure and mitral regurgitation were included. Patients were stratified into three groups according to vena contracta width as having mild (n = 11), moderate (n = 11) and severe mitral regurgitation (n = 10). The elongation index (EI) was considered as equal to {[(left ventricular internal area-measured) - (theoretical area of the sphere with measured left ventricular volume)]/(theoretical area of the sphere with measured left ventricular volume)}. Ejection fractions by the modified Simpson rule, dP/dt and sphericity index (SI) were also recorded. The relationship between (EI), ejection fraction, dP/dt and SI reached modest statistical significance (p < 0.05). When the EI and SI were compared, the correlation was also significant (p < 0.01). The areas under the receiver operator curve of EI and SI for discriminating dP/dt < 1000 mm Hg/s were 0.833 and 0.733, respectively. In conclusion, the elongation, which defines the shape of the left ventricle, might be related to the systolic function of the left ventricle and the degree of the mitral regurgitation. Further studies are needed to demonstrate its use in other clinical entities.  相似文献   
967.
AIM: To assess the practically usefulness and diagnostic yield of this new method in a group of patients with suspected small bowel lesions. METHODS: Capsule endoscopic (CE) examination by using M2A capsule endoscope TM (Given Imaging, Yoqneam, Israel) was performed in thirty nine patients (26 males, 13 females) with suspected small intestinal lesions. The composing of the patients was as follows: obscure gastrointestinal bleeding in twenty three patients, known Crohn's disease in 6 patients, in whom CE was used to evaluate the severity and extension of the diseases, chronic diarrhea in 8 patients, abdominal pain in one patient and malignancy in one patient with unknown origin. RESULTS: In two patients CE failed. Different abnormalities were revealed in 26 patients overall. Detection rate of abnormalities was highest among patients with obscure gastrointestinal bleeding and the source of bleeding was demonstrated in 17 of 23 patients with obscure bleeding (73.9%). Entero-Behcet was diagnosed in two patients by CE as a source of obscure gastrointestinal bleeding. In 6 patients with known Crohn's disease, CE revealed better evaluation of the disease extension. In 3 of 8 (37.5%) patients with chronic diarrhea; CE revealed some mucosal abnormalities as the cause of chronic diarrhea. In a patient with unexplained abdominal pain and in a cancer patient with unknown origin, CE examination was normal. CONCLUSION: In our relatively small series, we found that capsule endoscopy is a useful diagnostic tool particularly in diagnosis of obscure gastrointestinal bleeding, chronic diarrhea and in estimating the extension of Crohn's disease.  相似文献   
968.
This study investigated the effect of taper and apical preparation size on the fracture resistance of roots. 84 mandibular incisor teeth were selected. Groups (n = 12): uninstrumented (control group), 25/0.04, 25/0.06, 25/0.08, 30/0.04, 30/0.06 and 30/0.08. K3XF files (Kerr Endodontics, Orange, CA) were used for canal preparation. Fracture resistance was tested using a Universal test machine. For statistical analysis, the level of significance was P ≤ 0.05, and one‐way anova and post hoc LSD tests were used. The control group showed the highest fracture resistance (P < 0.05). No significant difference was found between 25/0.04 and 25/0.06; 25/0.06 and 25/0.08; 30/0.04 and 30/0.06; 30/0.06 and 30/0.08; 25/0.04 and 30/0.04; 25/0.06 and 30/0.06; and 25/0.08 and 30/0.08 (P > 0.05). Significant differences were found between 25/0.04 and 25/0.08; 30/0.04 and 30/0.08; and 25/0.08 and 30/0.04 (P < 0.05). In conclusion, the clinical selection of larger tapers can cause a higher risk of fracture.  相似文献   
969.
BackgroundRelation of serum gamma-glutamyl transferase (GGT) levels with extent, severity, and complexity of coronary artery disease has not been adequately studied. Therefore, we evaluated the relationship between GGT levels and coronary complexity, severity and extent assessed by SYNTAX score and long-term adverse events.MethodsWe enrolled 442 consecutive patients with stable angina pectoris who underwent coronary angiography. Baseline serum GGT levels were measured and SYNTAX score was calculated from the study population. Median follow-up duration was 363 days. Endpoints were all cause mortality and any revascularization.ResultsGGT levels demonstrated an increase from low SYNTAX tertile to high tertile. In multivariate analysis serum GGT, diabetes mellitus, HDL-cholesterol, eGFR and ejection fraction were found to be independent predictors of high SYNTAX score. The survival analysis showed that long-term revascularization rates were comparable between the GGT groups (for 36 U/l cut point) of the overall population (7.7% vs 8.6% logrank, p = 0.577), whereas long-term all cause mortality rate was higher in the GGT  36 U/l group (3.6% vs 11.6% logrank, p = 0.001). In Cox proportional hazards regression model, GGT  36 U/l group was found to be an independent predictor of long-term all cause mortality in the unadjusted (HR 2.54, 95% CI 1.17–5.48, p = 0.018) and age- and gender-adjusted (HR 2.58, 95% CI 1.19–5.58, p = 0.016) models.ConclusionSerum GGT level was independently associated with coronary complexity and long-term mortality in patients with stable coronary artery disease.  相似文献   
970.
Aim: Celiac disease is characterized by malabsorption resulting from inflammatory injury to the mucosa of the small intestine after the ingestion of wheat gluten or related rye and barley proteins. This study aimed to identify individuals who are at risk of heart failure and increased risk for cardiovascular events by evaluating endothelial function in patients with celiac disease. Materials and Methods: The study included 36 patients with celiac disease and 35 healthy volunteers. After all routine laboratory examination, left ventricular functions were evaluated with standard two‐dimensional, M‐mode conventional Doppler methods. Then, flow‐mediated dilatation and nitroglycerin‐dependent dilatation tests on brachial artery were performed to all patients and controls. Results: A total of 36 celiac patients and 35 healthy volunteers were included in the study. The brachial artery diameter at baseline was similar between both groups. Measured brachial artery diameter after hyperemia was 30.19 ± 4.47 mm in celiac patients and 32.35 ± 3.77 mm in the control group. Differences between two groups were statistically significant (P = 0.031). Flow‐mediated vasodilatation was lower in celiac patients compared with in controls (10.61 ± 2.64% vs 13.09 ± 2.9%; P = 0.0003). Measured endothelium‐independent vasodilatation in the brachial artery before and after nitroglycerin was similar between both groups (P = 0.09 and P = 0.07, respectively). Conclusion: This research which aimed to evaluate endothelial dysfunction in patients with celiac disease is the first in the literature. As a result of this study, we found endothelial dysfunction at the macrovascular level in celiac patients. (Echocardiography 2012;29:471‐477)  相似文献   
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