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排序方式: 共有392条查询结果,搜索用时 390 毫秒
81.
The aim of the study was to assess the relationship between ischemic cerebrovascular accidents (ICVAs), that is, transient ischemic attack (TIA) or stroke, and left-sided heart valve abnormalities (LHVAs) in patients with systemic lupus erythematosus (SLE). In total, 71 consecutive SLE patients were studied. At baseline, history, clinical and laboratory evaluations, as well as trans-thoracic echocardiography (TTE) were performed. From the original population, so patients were followed up for a mean time of 5.80 +/- 1.53 years. After a mean period of 5.39 +/- 1.42 years; 40 patients underwent a repeat TTE. Previous ICVA history was present at baseline in 16 patients (22.5%). Of these, 13 (81.2%) had evidence of LHVAs on TTE. Previous ICVAs were significantly associated to diagnosis of secondary anti-phospholipid syndrome (SAPS), positivity for anti-cardiolipin antibodies (aCl), and LHVAs. Multivariate analysis confirmed the correlation between previous ICVAs and LHVAs. LHVAs were not more commonly observed in patients with SAPS compared to patients without SAPS. At the end of follow-up, irrespective of any differences in antithrombotic treatment, ICVAs had occurred in 13 patients. During follow-up, ICVAs had recurred in seven patients, while a first event TIA occurred in one patient. Multivariate analysis confirmed the relationship between ICVAs and LHVAs, and a trend towards a positive correlation of the former with SAPS. This study demonstrates that LHVAs represent a compelling risk factor for the development of ICVAs in SLE patients. Conversely, SAPS and aCl positivity, although associated with ICVAs, did not clearly correlate with LHVAs in our study. These results provide insight on the pathogenesis of ICVAs and may give clues on the potential efficacy of preventive/therapeutic strategies in different SLE subpopulations.  相似文献   
82.
OBJECTIVE: The aim of this study was to evaluate the exercise tolerance by expired gas analysis during stress test in patients with Systemic Sclerosis (SSc). METHODS: Eighteen women (mean age 48.56+/-12.48 years) affected by SSc were studied. A complete echocardiographic examination including pulmonary artery systolic pressure estimation, pulmonary function tests, diffusion lung capacity for carbon monoxide (DLCO), and exercise test were performed. During exercise, breath-by-breath expired gas analysis was performed. RESULTS: Seven patients (39%) had baseline pulmonary systolic hypertension (group A) and 11 patients (61%) did not (group B). Six patients had reduced DLCO values. Both maximal oxygen consumption (VO2max) and anaerobic threshold (VO2AT) values were markedly decreased compared to the predicted values. Seven of 18 patients were unable to complete a maximal exercise (5 of whom affected by pulmonary systolic hypertension). Group A patients showed reduced VO2max, VO2AT, and O2 pulse compared with patients with group B patients (p=0.004, 0.017, and 0.013, respectively); VO2max, VO2AT and O2 pulse were significantly correlated to baseline pulmonary artery systolic pressure. CONCLUSIONS: An exercise intolerance in patients affected by SSc is present. Impairment of exercise performance is associated with pulmonary hypertension.  相似文献   
83.
INTRODUCTION: The use of peppermint oil in treating the irritable bowel syndrome has been studied with variable results probably due to the presence of patients affected by small intestinal bacterial overgrowth, lactose intolerance or celiac disease that may have symptoms similar to irritable bowel syndrome. AIM: The aim of the study was to test the effectiveness of enteric-coated peppermint oil in patients with irritable bowel syndrome in whom small intestinal bacterial overgrowth, lactose intolerance and celiac disease were excluded. METHODS: Fifty-seven patients with irritable bowel syndrome according to the Rome II criteria, with normal lactose and lactulose breath tests and negative antibody screening for celiac disease, were treated with peppermint oil (two enteric-coated capsules twice per day or placebo) for 4 weeks in a double blind study. The symptoms were assessed before therapy (T(0)), after the first 4 weeks of therapy (T(4)) and 4 weeks after the end of therapy (T(8)). The symptoms evaluated were: abdominal bloating, abdominal pain or discomfort, diarrhoea, constipation, feeling of incomplete evacuation, pain at defecation, passage of gas or mucus and urgency at defecation. For each symptom intensity and frequency from 0 to 4 were scored. The total irritable bowel syndrome symptoms score was also calculated as the mean value of the sum of the average of the intensity and frequency scores of each symptom. RESULTS: At T(4), 75% of the patients in the peppermint oil group showed a >50% reduction of basal (T(0)) total irritable bowel syndrome symptoms score compared with 38% in the placebo group (P<0.009). With peppermint oil at T(4) and at T(8) compared with T(0) a statistically significant reduction of the total irritable bowel syndrome symptoms score was found (T(0): 2.19+/-0.13, T(4): 1.07+/-0.10*, T(8): 1.60+/-0.10*, *P<0.01 compared with T(0), mean+/-S.E.M.), while no change was found with the placebo. CONCLUSION: A 4 weeks treatment with peppermint oil improves abdominal symptoms in patients with irritable bowel syndrome.  相似文献   
84.
Dopamine interrupts gastrointestinal fed motility pattern in humans   总被引:3,自引:0,他引:3  
The aim of this study was to investigate the hypothesis that during the postprandial period in humans, dopamine interrupts the gastrointestinal motility pattern through a mechanism that is peptide-mediated. Fourteen normal human subjects were studied by means of intestinal manometry. After recording two consecutive migrating motor complexes a 900-kcal solid-liquid meal was given. In eight subjects 30 min after the meal, placebo or dopamine (5 micrograms/kg/min) was infused for 15 min and then the recording continued for 120 min. In the remaining six subjects dopamine was administered twice with a 90-min interval in between. In three subjects the first dopamine infusion after the meal was preceded by treatment with placebo, the second by domperidone (20 mg intravenous as bolus), in the other three subjects domperidone was given before the first dopamine infusion. Blood samples for the determination of somatostatin and motilin were drawn basally, during, and immediately after dopamine in seven subjects. The results show that dopamine interrupts the fed motility pattern, inhibiting the high antral waves, and activates a duodenal phase III of migrating motor complexes. The pretreatment with domperidone completely prevented the dopamine effect. Plasma levels of motilin increased significantly during dopamine, while somatostatin blood levels did not change. These findings support the hypothesis that a dopaminergic mechanism may modulate the cycling of duodenal motor complex in humans.  相似文献   
85.
86.
OBJECTIVE: Growth hormone deficiency (GHD) in adults is associated with increased oxidative stress determined by the underlying GH-IGF-1 axis alterations. Despite GHD being a common diagnosis in children with short stature, no data on the oxidant/antioxidant status are available in this age group. This study was designed to detect differences in oxidative stress parameters between prepubertal GH-deficient children and healthy controls. Furthermore, the effect of 12 months of conventional GH replacement (rGH) on oxidant-antioxidant status was evaluated in the GHD group only. PATIENTS: Ten (nine males and one female) prepubertal children (mean age 9.1 +/- 1.3 years) with GHD were recruited and matched for sex and age (9.2 +/- 1.9 years) with 20 healthy controls (18 males and two females). MEASUREMENTS: At study entry, lag phase, an index of susceptibility of low density lipoprotein (LDL) to in vitro oxidation, malondialdehyde (MDA) and vitamin E were measured in all subjects. These parameters were also evaluated in GH-deficient children after 12 months of rGH treatment. RESULTS: The lag phase was significantly decreased in GH-deficient children compared to healthy controls (15.50 +/- 7.4 vs. 43.00 +/- 9.2 min; P = 0.0007), while MDA was significantly increased (1.33 +/- 0.38 vs. 0.46 +/- 0.10 nmol/mg; P = 0.0006). Vitamin E levels were significantly decreased (22.44 +/- 9.57 vs. 35.38 +/- 16.49 micromol/l; P = 0.001). IGF-1 and IGFBP-3 correlated directly to lag phase (r = 0.48; P = 0.01; r = 0.63, P = 0.002, respectively) and to vitamin E (r = 0.59, P = 0.003; r = 0.58, P = 0.006, respectively). By contrast, IGF-1 and IGFBP-3 correlated indirectly to MDA (r = -0.47, P = 0.01; r =-0.65, P = 0.002, respectively). After 1 year of rGH therapy, lag phase (39.32 +/- 15.24 min; P = 0.005) and vitamin E (34.9 +/- 7.7 micromol/l; P = 0.005) increased significantly, while MDA decreased significantly (0.71 +/- 0.42 nmol/mg; P = 0.005), reaching normal levels. CONCLUSIONS: These data show that children with GHD have substantially increased oxidative stress parameters compared to healthy controls and demonstrate a normalization of these parameters after 1 year of rGH therapy.  相似文献   
87.

Background

Obesity is associated with a high risk of coronary artery disease morbidity and mortality. Yet, postmortem studies have shown that severely obese subjects exhibit smooth coronary arteries, thus suggesting that they may be protected from atherosclerosis. We assessed vascular function and its possible determinants in a cohort of normal-weight to severely obese insulin-sensitive subjects (body mass index [BMI] 23.2-49 kg/m2).

Methods

Seventy-one healthy, insulin-sensitive subjects (Homeostasis Model Assessment of Insulin Resistance index <2.5), divided into normal-weight (n = 13; BMI = 23.2 ± 1.6), obese (n = 35; BMI = 32.6 ± 2.5), and severely obese (n = 23; BMI = 49.0 ± 7.9) groups, were enrolled. Vascular function was evaluated by flow-mediated dilation and carotid intima-media thickness. High-sensitivity C-reactive protein, leptin, adiponectin, vascular growth factors, and CD34+KDR+/CD133+ endothelial progenitor cells, known markers of vascular health/protection, also were measured.

Results

Flow-mediated dilation was higher in severely obese than in obese and normal-weight individuals (P = .019 and P = .011 respectively). Intima-media thickness was consistently lower in severely obese than in obese individuals (P = .040) and similar in severely obese and normal-weight individuals (P >.99). Levels of high-sensitivity C-reactive protein and leptin were higher in severely obese than in obese and normal-weight individuals (high-sensitivity C-reactive protein: P = .018 and P = .05, respectively; leptin: P <.001 for both comparisons). CD34+KDR+ endothelial progenitor cells were significantly higher in severely obese versus obese individuals (P = .039).

Conclusion

Our study demonstrates that vascular function is paradoxically better in severely obese than in obese subjects and similar to that found in normal-weight subjects. Despite higher levels of high-sensitivity C-reactive protein and leptin, severely obese individuals may be partially protected from atherosclerosis, possibly by a greater mobilization of endothelial progenitor cells.  相似文献   
88.
Objective. To assess the relationship between the presence of mixed infection of Helicobacter pylori and both antimicrobial susceptibility and virulence markers. Material and methods. Thirty-six patients with H. pylori infection were included in the study. Three colonies were selected from each positive biopsy sample collected from each host for a total of 108 H. pylori strains. The genetic variability was evaluated through the amplified fragment length polymorphism (AFLP) analysis; the antibiotic susceptibility to amoxicillin, clarithromycin, moxifloxacin, rifabutin and tinidazole was determined using the minimum inhibitory concentrations (MICs) with the agar dilution method. Moreover, the vacA, cagA, iceA and babA2 statuse were detected by polymerase chain reaction (PCR). Results. There was a strong connection between mixed H. pylori infection and antimicrobial resistance. In particular, H. pylori strains with genetic variability, in the same host, expressed more resistance to clarithromycin, moxifloxacin and tinidazole than that expressed in strains with a unique genetic host pattern. VacA s1m1/s1m2 genotypes were found in 70% of strains isolated in mixed infection, whereas the same allelic combinations were found in 42% of strains, isolated in single infection. The cagA+ status prevailed both in patients with mixed (97%) and in those with single infection (85%) without significant differences. The iceA1 status was more commonly found in patients with mixed infection, whereas the babA2 status was significantly prevalent in single H. pylori infection. Conclusions. Mixed H. pylori infection harbouring in one patient is significantly related to strains that are more resistant to antibiotics and with a more virulent genotype (vacA s1m1/s1m2, cagA, iceA1) than strains responsible for single infection.  相似文献   
89.
Intracoronary injection of bone marrow stem cells seems to improve left ventricular (LV) function after acute myocardial infarction (AMI). Granulocyte colony-stimulating factor (G-CSF) could improve myocardial function and perfusion noninvasively through mobilization of stem cells into peripheral blood, although previous clinical trials have produced controversial results. Forty-one patients with large anterior wall AMI at high risk of unfavorable remodeling were randomized 1:2 to G-CSF (10 microg/kg/day for 5 days) or to conventional therapy. All patients underwent successful primary or rescue percutaneous coronary intervention. LV function was assessed by echocardiography before G-CSF administration, > or =5 days after AMI, and at follow-up. Only patients with a LV ejection fraction <50% at baseline were enrolled in the study. After a median follow-up of 5 months (range 4 to 6) patients treated with G-CSF exhibited improvement in LV ejection fraction, from 40 +/- 6% to 45 +/- 6% (p = 0.068) in the absence of LV dilation (LV end-diastolic volume from 147 +/- 33 to 144 +/- 46 ml at follow-up, p = 0.77). In contrast, patients treated conventionally exhibited significant LV dilation (LV end-diastolic volume from 141 +/- 35 to 168 +/- 41 ml, p = 0.002) in the absence of change in LV ejection fraction (from 38 +/- 6% to 38 +/- 8%, p = 0.95). However, when comparing patients treated with G-CSF with controls, variations in these parameters were significantly different at 2-way analysis of variance (p = 0.04 for LV end-diastolic volume, p = 0.02 for LV ejection fraction). In conclusion, G-CSF prevents unfavorable LV remodeling and improves LV function in patients with large anterior wall AMI and decreased LV ejection fraction after successful percutaneous coronary intervention.  相似文献   
90.
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