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991.
992.
BACKGROUND: Quadruple therapy with a proton pump inhibitor, bismuth, metronidazole and tetracycline is recommended as the optimal second-line therapy of Helicobacter pylori infection in the Maastricht Consensus Report. The aim of the present paper was to evaluate the efficacy of ranitidine bismuth citrate (RBC)-based regimens as second-line therapies after failure of the standard Maastricht triple therapy. MATERIALS AND METHODS: One hundred and sixteen H. pylori-positive patients were given omeprazole 20 mg b.d., clarithromycin 500 mg b.d., and amoxicillin 1 g b.d for 10 days. Patients remaining H. pylori-positive (n = 29) were combined with 27 patients enrolled after an initial eradication failure from proton-pump inhibitor (PPI), amoxicillin and clarithromycin therapy for at least 7 days and were randomly given one of the following second-line 10-day treatments: RBC 400 mg b.d., amoxicillin 1 g b.d and clarithromycin 500 mg b.d. (RAC group, n = 28) and RBC 400 mg b.d., metronidazole 500 mg b.d and tetracycline 500 mg b.d. (RMT group, n = 28). Eradication was assessed by either histology and rapid urease test or (13)C urea breath test 8 weeks after therapy. RESULTS: The eradication rate of first-line Maastricht therapy was 67% for intention-to-treat analysis (95% confidence interval [CI]: 58-75). Per-protocol and intention-to-treat eradication was achieved in 60.7% of patients (95%CI: 42-79) in the RAC group and in 85.7% of patients (95%CI: 73-98) in the RMT group (P = 0.03). Fifty-three percent of patients in the RAC and 50% of patients in the RMT group experienced at least one slight side-effect (P = 0.6). CONCLUSIONS: RMT is an effective and well-tolerated second-line therapy after H. pylori eradication failure from PPI, amoxicillin, and clarithromycin.  相似文献   
993.
OBJECTIVE: Thrombophilic gene mutations have been reported to be associated with the formation of portal vein thrombosis (PVT). This study aimed to investigate the role of thrombophilic gene mutations in cirrhotic patients with PVT. PATIENTS AND METHODS: A total of 74 cirrhotic patients (17 with PVT, 57 without PVT), and 19 non-cirrhotic patients with PVT and 80 healthy controls were included. Factor V Leiden G1691A, prothrombin G20210A and methylenetetrahydrofolate reductase C677T mutations were analysed by restriction fragment length polymorphism. RESULTS: Aetiologies and Child-Pugh distribution of cirrhotic patients with and without PVT were similar. Five of 17 (29%) of cirrhotic patients with PVT but only two of 57 (3.5%) of cirrhotics without PVT, five of 80 (6%) of controls and none of the 19 non-cirrhotic patients with PVT had factor V Leiden G1691A mutation (P<0.05). Prothrombin G20210A mutation was found in five (29%) cirrhotic patients with PVT while only two (3.5%) cirrhotic patients without PVT, one (5%) non-cirrhotic patient with PVT and two (2.5%) controls had this mutation (P<0.05). The frequency of the homozygote methylenetetrahydrofolate reductase 677C-T mutation was similar in all four groups. CONCLUSIONS: Inherited thrombophilic gene mutations appear to increase the risk of PVT formation in cirrhotic patients but not in patients without liver disease in a cohort of Turkish patients.  相似文献   
994.
Background Electrical field stimulation of gallbladder muscle strips produces frequency-dependent contractions by activating cholinergic nerves. The cholinergic motor function of the gallbladder and enteric system is also modulated by other mediators. The aim of this study was to investigate the role of agmatine, a ligand for alpha 2-adrenoceptors and imidazoline binding sites, in the cholinergic motor activity of guinea pig gallbladder smooth muscle.Methods Gallbladder muscle strips obtained from guinea pigs were subjected to electrical field stimulation (1–64Hz, 100V, 1-ms pulse width, and 10-s train duration). Frequency-response contractions of gallbladder muscle strips were traced before and after the addition of cumulative concentrations of agmatine (10–5–10–3M) to the tissue bath. The same set of experiments was repeated in the presence of different antagonists.Results Agmatine by itself did not produce any contractions in guinea pig gallbladder muscle strips, but significantly enhanced the contractile response produced by electrical field stimulation. Yohimbine (10–6M), a selective alpha 2-adrenergic blocker, neither decreased nor increased the enhancement induced by agmatine. However, idazoxan (10–4M), an alpha-receptor blocker and imidazoline receptor antagonist, abolished this enhanced contractile response. Pretreatment with NW-nitro l-arginine methyl ester (l-NAME; 30µM), and indomethacin (10µM) did not inhibit the effect of agmatine.Conclusions Our findings indicate that agmatine has a modulator role in the electrical field stimulation-induced cholinergic contractions of guinea pig gallbladder smooth muscle strips, and this role could be mediated by imidazoline receptors. Receptor binding studies should be done to determine the presence of endogenous agmatine and imidazoline receptors in gallbladder smooth muscle.  相似文献   
995.
BACKGROUND AND AIMS OF THE STUDY: The presence of significant atherosclerotic coronary artery disease (CAD) in patients with valvular heart disease is an important predictor of perioperative mortality. The prevalence of CAD in patients undergoing valvular heart surgery is 20-40% in industrialized countries. The study aim was to determine CAD prevalence in Turkish patients undergoing valvular heart surgery, and to identify predictors of its presence. METHODS: A total of 760 patients (357 males, 403 females; mean age 54.4+/-18.1 years) who underwent coronary angiography before valvular surgery between 1995 and 2000 was enrolled retrospectively. Single- and multi-valve involvement was present in 46% and 54% of patients, respectively. Patients with ischemic mitral regurgitation were excluded from the study. Significant CAD was defined as the presence of > or =50% diameter stenosis anyone of the coronary arteries. The presence of angina pectoris, and of risk factors (e.g. hypertension, smoking, diabetes mellitus (DM), hyperlipidemia, family history of CAD) were sought in all patients. Predictors of CAD were identified by logistic regression analysis. RESULTS: Significant CAD was present in 15.8% of patients (24% males, 9% females) (p <0.001); the highest prevalence was in those with aortic stenosis (p <0.05). CAD was not seen in young patients (aged <45 years) with none of the above-mentioned risk factors. The highest correlation between CAD and risk factors was family history of CAD, followed by DM, hyperlipidemia, hypertension and smoking, in decreasing order. CONCLUSION: The study results showed that CAD in patients with valvular heart disease was less prevalent in Turkey than in industrialized countries. The incidence of coronary lesions rises notably from the age of 50 years in both males and females. Coronary angiography before valvular heart surgery could be omitted in young patients (age <45 years) with none of the coronary risk factors, or without angina.  相似文献   
996.
Nine cases of intrathoracic lipoma are reported. Computed tomography (CT) proved to be helpful in the diagnosis and management of these cases. The attenuations of the masses ranged from -70 to -140 Hounsfield units (HU). In 4 cases, needle biopsies were taken, confirming lipoma with mature fat cells. One patient also had a coelomic cyst with an attenuation of 20 HU, which was confirmed at thoracotomy. Another had an atypical lipoma which infiltrated the thoracic wall but was benign. In conclusion, we recommended investigation with CT scan for the diagnosis of lipoma.  相似文献   
997.
OBJECTIVE: Women with polycystic ovary syndrome (PCOS) exhibit elevated levels of serum C-reactive protein (CRP) and impaired endothelium dysfunction which are directly correlated with insulin resistance. Because rosiglitazone improves insulin sensitivity, we tested whether rosiglitazone treatment ameliorates high-sensitivity (hs)CRP levels and endothelial dysfunction in these patients. DESIGN: Thirty-one women with PCOS were recruited (mean age, 24.7+/-3.9 (s.e.) years; mean body mass index (BMI), 25.6+/-3.2 kg/m2). All women were treated with 4 mg rosiglitazone daily for 12 months. METHODS: Serum levels of testosterone, LH, FSH, sex hormone-binding globulin (SHBG), insulin and hsCRP were measured. The BMI, hirsutism scores and insulin sensitivity indices were calculated before and after treatment. Arterial endothelium and smooth muscle function was measured by examining brachial artery responses to endothelium-dependent and endothelium-independent stimuli before and after treatment. RESULTS: After treatment with rosigitazone there were significant decreases in serum testosterone (91.2+/-37.5 vs 56.1+/-21.8 ng/dl; P < 0.01) and fasting insulin concentrations (12.5+/-7.6 vs 8.75+/-4.03 microU/ml; P = 0.015). Insulin resistance indices were significantly improved after rosiglitazone treatment (P < 0.05). There were no significant changes in BMI, waist circumference, serum total cholesterol, low-density lipoprotein (LDL)-cholesterol, FSH and LH levels. Hirsutism score was decreased significantly after treatment (10.8+/-1.8 vs 7.6+/-1.7; P < 0.05). Twenty-four of the women reverted to regular menstrual cycles. Levels of SHBG increased significantly after treatment (28.7+/-8.7 vs 48.4+/-11.2 nmol/l; P < 0.01). Serum hsCRP levels were decreased significantly after rosiglitazone treatment (0.25+/-0.1 vs 0.09+/-0.02 mg/dl; P = 0.006). There was also significant improvement in endothelium-dependent vascular responses after rosiglitazone treatment (9.9+/-3.9 vs 16.4+/-5.1%; P < 0.01). CONCLUSIONS: We conclude that rosiglitazone treatment improves insulin sensitivity in women with PCOS. It also decreases androgen production without significant weight gain. More importantly, it has beneficial effects on endothelial dysfunction and low-grade chronic inflammation in normal weight young women with PCOS.  相似文献   
998.
BACKGROUND/AIMS: Gastroesophageal reflux is considered as a factor in pulmonary diseases. The aim of this study was to assess whether gastroesophageal reflux is associated with abnormalities in lung function in patients without respiratory disease. METHODS: Forty- four patients with reflux symptoms were studied prospectively. Standardized methods of esophageal manometry and ambulatory 24-h esophageal pH testing were used throughout the study period, along with a standardized reflux and respiratory symptom questionnaire. Spirometric measurements were performed in all patients. RESULTS: Reflux to distal esophagus was observed in 9 patients, to proximal esophagus in 4 and to both distal and proximal in 20 of the 44 patients. Eleven patients revealed reflux neither to distal nor proximal esophagus. Respiratory function tests of these groups showed no significant differences (p>0.05). CONCLUSION: There is no correlation between esophageal acid events and respiratory function tests. There are no data to answer the question of whether or not reflux precedes onset of cough/asthma. Better-designed prospective cohort studies may provide further insight.  相似文献   
999.
BACKGROUND: The aim of the present study was to investigate whether the von Willebrand factor levels, as a possible indicator of endothelial dysfunction, is increased in hypertrophic cardiomyopathy, and also whether it is related to the clinical status of hypertrophic cardiomyopathy. METHODS AND RESULTS: The study group comprised 29 patients with hypertrophic cardiomyopathy and 29 healthy age- and gender-matched control subjects. There was no significant difference in von Willebrand factor levels between study group (77.0 +/- 23.1%) and control group (88.5 +/- 34.2%). There was no statistically significant difference between control group (88.5 +/- 34.2%) and functional class I/II group (82.0 +/- 24.3%), between control group and functional class III group (67.6 +/- 18.3%) and between functional class I/II group and functional class III group with respect to the von Willebrand factor levels. CONCLUSIONS: The results suggest that von Willebrand factor levels, as a possible indicator of endothelial dysfunction, are not increased in patients with hypertrophic cardiomyopathy and von Willebrand factor levels are not related to functional class in these patients.  相似文献   
1000.
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