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991.
We analyzed the clinical, angiographic, and late intravascular ultrasonographic findings from 140 patients whose in-stent restenosis was treated with sirolimus-eluting stents. In-stent restenosis remains the main limitation to percutaneous coronary revascularization and has a high recurrence rate after bare stent implantation. From May 2002 through July 2003, we studied 140 patients with clinical restenosis after bare-stent treatment. In 107 patients, in-stent restenosis occurred de novo; in 28 patients, this was the 2nd restenosis; and in another 5, it was the 3rd occurrence. A sirolimus-eluting stent was implanted directly after angiographic evaluation of the in-stent restenosis in 79 patients and after pre-dilation in 61 patients. All patients were given the following antithrombotic regimen: low-molecular-weight heparin, ticlopidine, and aspirin for 1 month, followed by clopidogrel and aspirin for 1 year. Primary success was achieved in 137 patients. Three patients had a non-Q wave myocardial infarction. At the 1-month evaluation, 2 patients had died: 1 due to subacute stent thrombosis and another due to acute mesenteric ischemia. After a mean follow-up of 16 +/- 4 months, the major adverse cardiac events were acute myocardial infarction due to late stent thrombosis in 2 patients and the need for target lesion revascularization in 15 patients. Late angiographic evaluation was performed in 97 patients (69%), 16 of whom had new restenosis: 14 of the restenoses were intrastent, and 2 were at the edges of the stent. Our results suggest that sirolimus-eluting stents are effective in the prevention of in-stent restenosis and, therefore, may become the leading treatment alternative for patients with in-stent restenosis.  相似文献   
992.
Aim:The aim of this study was to determine whether the influence of insulin therapy on fasting and stimulated C-peptide levels in type 2 diabetic subjects is due to plasma glucose reduction or a direct effect of exogenous insulin.Methods:Plasma glucose and serum C-peptide levels were determined before and after IV injection of 1 mg glucagon on three separate days in 21 type 2 diabetic subjects. Day 1: without pharmacological treatment and fasting plasma glucose >11.1 mmol/L; day 2: fasting plasma glucose 4.4–7.8 mmol/L, 1 h after withdrawing intravenous regular insulin infusion; day 3: fasting plasma glucose 4.4–7.8 mmol/L with bed-time NPH insulin.Results:Fasting and glucagon stimulated C-peptide levels were higher on day 1 than days 2 and 3. Fasting, but not stimulated C-peptide levels, were lower on day 3 than day 2. These differences were not appeared when the percentage of C-peptide increment or the C-peptide/glucose ratio were compared in the three days.Conclusions:Blood glucose reduction instead of exogenous insulin is responsible for the C-peptide decrease during insulin therapy in type 2 diabetic subjects.  相似文献   
993.
The protein storage vacuole (PSV) is a plant-specific organelle that accumulates reserve proteins, one of the main agricultural products obtained from crops. Despite the importance of this process, the cellular machinery required for transport and accumulation of storage proteins remains largely unknown. Interfering with transport to PSVs has been shown to result in secretion of cargo. Therefore, secretion of a suitable marker could be used as an assay to identify mutants in this pathway. CLV3, a negative regulator of shoot stem cell proliferation, is an extracellular ligand that is rendered inactive when targeted to vacuoles. We devised an assay where trafficking mutants secrete engineered vacuolar CLV3 and show reduced meristems, a phenotype easily detected by visual inspection of plants. We tested this scheme in plants expressing VAC2, a fusion of CLV3 to the vacuolar sorting signal from the storage protein barley lectin. In this way, we determined that trafficking of VAC2 requires the SNARE VTI12 but not its close homologue, the conditionally redundant VTI11 protein. Furthermore, a vti12 mutant is specifically altered in transport of storage proteins, whereas a vti11 mutant is affected in transport of a lytic vacuole marker. These results demonstrate the specialization of VTI12 and VTI11 in mediating trafficking to storage and lytic vacuoles, respectively. Moreover, they validate the VAC2 secretion assay as a simple method to isolate genes that mediate trafficking to the PSV.  相似文献   
994.
BACKGROUND AND AIMS: Recent studies have reported an association between cytokine gene polymorphisms and GC risk. However, results are inconsistent among studies from different geographic regions and ethnic groups. Our goal was to evaluate the influence of Helicobacter pylori (H. pylori) infection and host genetic factors on GC susceptibility in a population of Spanish white GC patients. METHODS: DNA from 404 unrelated patients with GC and 404 sex- and age-matched healthy controls was typed for several functional polymorphisms in pro- (IL-1B, TNFA, LTA, IL-12p40) and anti-inflammatory (IL-4, IL-1RN, IL-10, TGFB1) genes by PCR, RFLP, and TaqMan assays. H. pylori infection and CagA/VacA antibody status were also determined by western blot serology. RESULTS: Logistic regression analysis identified H. pylori infection with cagA strains (OR 2.54, 95% CI 1.77-3.66), smoking habit (OR 1.91, 95% CI 1.25-2.93), and positive family history of GC (OR 3.67, 95% CI 2.01-6.71) as independent risk factors for GC. None of the cytokine gene polymorphisms analyzed in this study were associated with susceptibility to GC development, whether GC patients were analyzed as a group or categorized according to anatomic location or histological subtype. Some simultaneous combinations of proinflammatory genotypes reportedly associated with greater GC risk yielded no significant differences between patients and controls. CONCLUSIONS: Our results show that, at least in some white populations, the contribution of the cytokine gene polymorphisms evaluated in this study (IL-1B, IL-1RN, IL-12p40, LTA, IL-10, IL-4, and TGF-B1) to GC susceptibility may be less relevant than previously reported.  相似文献   
995.
OBJECTIVE: The aim of this study was to determine the prevalence of asymptomatic nasopharyngeal carriage of Streptococcus pneumoniae, which is a major factor in the transmission of this bacterium. MATERIAL AND METHODS: Nasopharyngeal cultures were performed on children attending 32 day-care centers in 12 states in Mexico. RESULTS: Streptococcus pneumoniae was isolated from the nasopharynx of 829 out of 2,777(29.9%) subjects aged two months to six years. All children lived in urban areas and 80% spent more than six hours daily in a day-care center. Streptococcus pneumoniae serotypes most frequently identified were: 19F (23%), 6B (15.6%), 23F (11.2%) and 6A (14.9%). Thirty-six percent of the isolates were susceptible to penicillin. CONCLUSIONS: Serotype distribution suggests the possible benefits that could be obtained from the heptavalent pneumococcal conjugate vaccine.  相似文献   
996.
Background and aimThe ankle-brachial index (ABI) is being used increasingly to diagnose peripheral arterial disease (PAD) that predicts cardiovascular morbidity and mortality. The aim of this study is to determine the prevalence of PAD and associated risk factors in a Spanish random population sample of age ≥40.Methods and resultsPAD is defined as an ABI < 0.9 in either leg. 784 participants of age ≥40 were randomly selected in a Spanish province. 55.4% of them were female. The prevalence of PAD in this sample was 10.5% (95% confidence interval (CI) 8.4–12.8); 9.7% in females and 11.4% in males. In logistic regression analyses, adjusted for age and gender, smoking per 10 pack-years (odds ratio (OR) 1.40, 95% CI 1.23–1.58), hypertension (OR 1.85, 95% CI 1.05–3.28), hypercholesterolemia (OR 1.76, 95% CI 1.04–2.98), and diabetes (OR 1.80, 95% CI 1.04–3.11) were positively associated with prevalent PAD. More than 91% of persons with PAD had one or more cardiovascular disease risk factors.ConclusionsWe conclude that in our study hypertension, hypercholesterolemia, diabetes mellitus and smoking are associated with PAD. The majority of individuals with PAD had at least one important cardiovascular risk factor advanced enough to be considered eligible for an aggressive treatment.  相似文献   
997.
Over the last 10 years, noninvasive ventilation has become a treatment option for respiratory insufficiency in pulmonology services. The technique is currently included in pulmonology teaching programs. Physicians and nurses should understand the devices they use and the interaction between the patient and the ventilator in terms of respiratory mechanics, adaptation, and synchronization. We present a readily assembled lung simulator for teaching purposes that is reproducible and interactive. Based on a bag-in-box system, this model allows the concepts of respiratory mechanics in mechanical ventilation to be taught simply and graphically in that it reproduces the patterns of restriction, obstruction, and the presence of leaks. It is possible to demonstrate how each ventilation parameter acts and the mechanical response elicited. It can also readily simulate asynchrony and demonstrate how this problem can be corrected.  相似文献   
998.
Inflammatory cloacogenic polyps are infrequent lesions that usually arise in the anorectal zone. The most common clinical presentation is rectal bleeding. Two cases of rectal bleeding related to cloacogenic polyps with different endoscopic appearance are reported. Endoscopists should be familiar with this entity, which should be considered in the differential diagnosis with other polypoid lesions observed in colonoscopy.  相似文献   
999.
Reactive oxygen species (ROS) in the brain are thought to contribute to the neuropathogenesis of hypertension by enhancing sympathetic nervous system activity. The nucleus tractus solitarius (NTS), which receives afferent input from baroreceptors, has an important role in cardiovascular regulation. reduced nicotinamide-adenine dinucleotide phosphate oxidase is thought to be a major source of ROS in the NTS. Rac1 is a small G protein and a key component of reduced nicotinamide-adenine dinucleotide phosphate oxidase. The role of Rac1-derived ROS in the NTS in cardiovascular regulation of hypertension is unknown. Therefore, we examined whether inhibition of Rac1 in the NTS decreases ROS generation, thereby reducing blood pressure in stroke-prone spontaneously hypertensive rats (SHRSPs). The basal Rac1 activity level in the NTS was greater in SHRSPs than in Wistar-Kyoto rats. Inhibition of Rac1, induced by transfecting adenovirus vectors encoding dominant-negative Rac1 into the NTS, decreased blood pressure, heart rate, and urinary norepinephrine excretion in SHRSPs but not in Wistar-Kyoto rats. Inhibition of Rac1 also reduced nicotinamide-adenine dinucleotide phosphate oxidase activity and ROS generation. In addition, Cu/Zn-superoxide dismutase activity in the NTS of SHRSPs was decreased compared with that of Wistar-Kyoto rats, despite the increased ROS generation. Overexpression of Cu/Zn-superoxide dismutase in the NTS decreased blood pressure and heart rate in SHRSPs. These results indicate that the activation of Rac1 in the NTS generates ROS via reduced nicotinamide-adenine dinucleotide phosphate oxidase in SHRSPs, and this mechanism might be important for the neuropathogenesis of hypertension in SHRSPs.  相似文献   
1000.
Objective  To compare pressure–volume (PV) curves obtained with the Galileo ventilator with those obtained with the CPAP method in patients with acute lung injury (ALI) or acute respiratory distress syndrome (ARDS). Design  Prospective, observational study. Setting  General critical care center. Patients and participants  Patients with ALI/ARDS and receiving mechanical ventilation. Interventions  Pressure–volume curves were obtained in random order with the CPAP technique and with the software PV Tool-2 (Galileo ventilator). Measurements and results  In ten consecutive patients, airway pressure was measured by a pressure transducer and changes in lung volume were measured by respiratory inductive plethysmography. PV curves were fitted to a sigmoidal equation with a mean R 2 of 0.994 ± 0.003. Intraclass correlation coefficients were all >0.75 (< 0.001 at all pressure levels). Lower (LIP) and upper inflection (UIP), and deflation maximum curvature (PMC) points calculated from the fitted variables showed a good correlation between methods with intraclass correlation coefficients of 0.98 (0.92, 0.99), 0.92 (0.69, 0.98), and 0.97 (0.86, 0.98), respectively (< 0.001 in all cases). Bias and limits of agreement for LIP (0.51 ± 0.95 cmH2O; −1.36 to 2.38 cmH2O), UIP (0.53 ± 1.52 cmH2O; −2.44 to 3.50 cmH2O), and PMC (−0.62 ± 0.89 cmH2O; −2.35 to 1.12 cmH2O) obtained with the two methods in the same patient were clinically acceptable. No adverse effects were observed. Conclusion  The PV Tool-2 built into the Galileo ventilator is equivalent to the CPAP method for tracing static PV curves of the respiratory system in critically ill patients receiving mechanical ventilation. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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