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991.
It is unknown if collateral circulation (CC) has a beneficial effect on outcomes of patients who undergo mechanical intervention in the first hours after onset of acute myocardial infarction (AMI). This study analyzes the relation between CC and outcome in patients with AMI who underwent primary angioplasty or stenting within 6 hours of symptom onset. The analysis was performed in a series of 1,164 consecutive patients. The contribution of clinical, angiographic, and procedural variables to the angiographic and clinical outcomes was evaluated by multivariate logistic regression analysis and the Cox proportional hazard model, respectively. Of 1,164 patients, 264 (23%) had angiographic evidence of CC. Patients with CC had a lower incidence of diabetes (11% vs 16%, p = 0.033), anterior AMI (41% vs 55%, p <0.001), cardiogenic shock (9% vs 14%, p = 0.029), anterograde TIMI grade flow >1 (10% vs 21%, p <0.001), and a greater incidence of preinfarction angina (43% vs 32%, p = 0.001), multivessel disease (59% vs 47%, p = 0.001), and total chronic occlusion (20% vs 10%, p <0.001). At 6 months, the mortality rate was lower in patients with CC compared with patients without CC (4% vs 9%, p = 0.011), whereas there were no differences in the incidence of reinfarction, target vessel revascularization, and angiographic restenosis. After multivariate analysis, CC did not emerge as a significant variable in relation to 6-month clinical and angiographic outcomes. CC does not exert a protective effect in patients who undergo mechanical intervention in the first 6 hours of AMI onset.  相似文献   
992.
Restenosis after percutaneous transluminal coronary angioplasty is caused by neointimal hyperplasia, which involves impairment of nitric oxide (NO)-dependent pathways, and may be further exacerbated by a concomitant aging process. We compared the effects of NO-releasing-aspirin (NCX-4016) and aspirin (ASA) on experimental restenosis in both adult and elderly rats. Moreover, to ascertain the efficacy of NCX-4016 during vascular aging, we fully characterized the release of bioactive NO by the drug. Sprague-Dawley rats aged 6 and 24 months were treated with NO releasing-aspirin (55 mg/kg) or ASA (30 mg/kg) for 7 days before and 21 days after standard carotid balloon injury. Histological examination and immunohistochemical double-staining were used to evaluate restenosis. Plasma nitrite and nitrate and S-nitrosothiols were determined by a chemiluminescence-based assay. Electron spin resonance was used for determining nitrosylhemoglobin. Treatment of aged rats with NCX-4016 was associated with increased bioactive NO, compared with ASA. NO aspirin, but not ASA, reduced experimental restenosis in old rats, an effect associated with reduced vascular smooth muscle cell proliferation. NCX-4016, but not ASA, was well tolerated and virtually devoid of gastric damage in either adult or old rats. Thus, impairment of NO-dependent mechanisms may be involved in the development of restenosis in old rats. We suggest that an NCX-4016 derivative could be an effective drug in reducing restenosis, especially in the presence of aging and/or gastrointestinal damage.  相似文献   
993.
994.
Resistin is overexpressed in human adipose tissue of obese individuals and is likely to modulate insulin sensitivity. Resistin is, therefore, a candidate gene for insulin resistance. We searched for polymorphisms in the resistin gene by single strand conformation polymorphism and direct sequencing. An ATG triplet repeat in the 3'-untranslated region was identified and considered for association with insulin resistance. Three alleles were identified (allele 1: 8 repeats, allele frequency, 0.3%; allele 2: 7 repeats; allele frequency, 94.5%; allele 3: 6 repeats; allele frequency, 5.2%). Two hundred and three unrelated white Caucasian nondiabetic subjects from Sicily and 456 from the Gargano area (center east coast of Italy) were analyzed. Among Sicilians, subjects carrying allele 3 had a lower fasting insulin and insulin resistance index (homeostasis model assessment of insulin resistance; P < 0.001 for both) and glucose (P = 0.025) and insulin (P = 0.002) levels during the oral glucose tolerance test. In subjects from Gargano, those carrying allele 3 had lower fasting plasma glucose levels and serum triglycerides (P = 0.01 for both). When the 2 populations were analyzed together, subjects carrying allele 3 had lower fasting insulin levels (P < 0.005), homeostasis model assessment of insulin resistance (P < 0.005), and serum triglycerides (P = 0.01). In conclusion, our data suggest that subjects carrying allele 3 of the resistin gene are characterized by relatively high insulin sensitivity.  相似文献   
995.
BACKGROUND & AIMS: This study was undertaken to prospectively compare the clinical outcomes of small bowel radiographs with the wireless capsule endoscopy. METHODS: Twenty-two patients were selected consecutively because of suspected small bowel disease. Two patients were excluded owing to ileal stenosis. Thus, the results of barium follow-through and the Given M2A wireless video capsule (Given Imaging Ltd., Yoqneam, Israel) endoscopy were compared in 20 patients (13 men; mean age, 52.5 yr; range, 29-78 yr). RESULTS: Barium follow-through was normal in 17 patients and showed ileal nodularity in 3 patients. Capsule endoscopy was normal in 3 patients and showed positive findings in the remaining 17 patients. The barium study was considered diagnostic in 4 (20%) patients. The capsule endoscopy was considered diagnostic in 9 (45%) patients, suspicious in 8 (40%) patients, and failed in 3 (15%) patients. For obscure gastrointestinal (GI) bleeding, the diagnostic potential of barium follow-through was much worse as compared with the capsule endoscopy (5% vs. 31%, P < 0.05). Capsule endoscopy was well tolerated and better accepted by patients when compared with the most recently performed endoscopic procedure. CONCLUSIONS: The video capsule endoscope was found to be superior to small bowel radiograph for evaluation of small bowel diseases. However, this novel wireless endoscope system needs further assessment because of limitations such as difficulties in interpretation of potentially nonspecific findings.  相似文献   
996.
In vitro removal of therapeutic drugs with a novel adsorbent system   总被引:1,自引:0,他引:1  
BACKGROUND/AIMS: Substances in the middle molecular weight range have been shown to play a significant pathogenetic role in as diverse disorders as end-stage renal disease and multiple organ failure. To overcome the limitations in the amount removed by hemofilters, new sorbents with a high biocompatibility are actively being developed. Furthermore, biocompatible sorbents by their nonspecific adsorptive behavior could have great impact on detoxification treatment in exogenous intoxications. We performed an in vitro evaluation of a newly developed highly biocompatible sorbent cartridge (Betasorb((R))), examining its adsorptive capacity concerning therapeutic drugs. METHODS: Uremic blood spiked with a range of therapeutic drugs was recirculated for 2 h in an in vitro hemoperfusion circuit containing a Betasorb device for hemoperfusion. The drug concentrations before and after the passage of the cartridge were measured, and the total amount removed was calculated. RESULTS: The sorbent showed effective removal of glycopeptide antibiotics, digoxin, theophylline, phenobarbital, phenytoin, carbamazepine, and valproic acid. Moderate removal could be demonstrated for tacrolimus and cyclosporine A; aminoglycosides were removed to a small extent only. CONCLUSION: Betasorb hemoperfusion shows a potent adsorptive capacity concerning therapeutic drugs (except aminoglycosides) and could be of major value in the treatment of intoxications. On the other hand, drug monitoring and possible adjustments are necessary during Betasorb hemoperfusion to maintain the therapeutic ranges of the drugs in blood.  相似文献   
997.
The effect of ethyl benzoate (EB) as a component of the solid catalyst (“internal” base) and/or of the co-catalyst (“external” base) on propene polymerization in the presence of different MgCl2-supported Ziegler-Natta systems was investigated systematically. From the experimental results, it is suggested that internal EB mainly prevents TiCl4 from coordination on the MgCI2 crystal faces where mostly non-stereospecific active sites would be formed, whereas external EB inhibits selectively the non-stereospecific centres and decreases the reaction of the alkylaluminium with the internal base. A possible model of active sites for isotactic 1-alkenes polymerization in the presence of MgCl2-supported catalysts is presented, which is in good agreement with a large number of known experimental facts.  相似文献   
998.
OBJECTIVE: Intraabdominal hypertension is associated with significant morbidity and mortality in surgical and trauma patients. The aim of this study was to assess, in a mixed population of critically ill patients, whether intraabdominal pressure at admission was an independent predictor for mortality and to evaluate the effects of intraabdominal hypertension on organ functions. DESIGN: Multiple-center, prospective epidemiologic study. SETTING: Fourteen intensive care units in six countries. PATIENTS: A total of 265 consecutive patients admitted for >24 hrs during the 4-wk study period. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Intraabdominal pressure was measured twice daily via the bladder. Data recorded on admission were the patient demographics with Simplified Acute Physiology Score II, Acute Physiology and Chronic Health Evaluation II score, and type of admission; during intensive care stay, Sepsis-Related Organ Failure Assessment score and intraabdominal pressure were measured daily together with fluid balance. Nonsurvivors had a significantly higher mean intraabdominal pressure on admission than survivors: 11.4 +/- 4.8 vs. 9.5 +/- 4.8 mm Hg. Independent predictors for mortality were age (odds ratio, 1.04; 95% confidence interval, 1.01-1.06; p = .003), Acute Physiology and Chronic Health Evaluation II score (odds ratio, 1.1; 95% confidence interval, 1.05-1.15; p < .0001), type of intensive care unit admission (odds ratio, 2.5 medical vs. surgical; 95% confidence interval, 1.24-5.16; p = .01), and the presence of liver dysfunction (odds ratio, 2.5; 95% confidence interval, 1.06-5.8; p = .04). The occurrence of intraabdominal hypertension during the intensive care unit stay was also an independent predictor of mortality (relative risk, 1.85; 95% confidence interval, 1.12-3.06; p = .01). Patients with intraabdominal hypertension at admission had significantly higher Sepsis-Related Organ Failure Assessment scores during the intensive care unit stay than patients without intraabdominal hypertension. CONCLUSIONS: Intraabdominal hypertension on admission was associated with severe organ dysfunction during the intensive care unit stay. The mean intraabdominal pressure on admission was not an independent risk factor for mortality; however, the occurrence of intraabdominal hypertension during the intensive care unit stay was an independent outcome predictor.  相似文献   
999.
Late motor recovery is influenced by muscle tone changes after stroke   总被引:5,自引:0,他引:5  
OBJECTIVES: To evaluate the time course of motor recovery in a poststroke period ranging from 2 to 6 months and its correlation with both the severity of motor deficit and the muscle tone disturbances (flaccidity or spasticity) of the affected limbs. DESIGN: Prospective cohort study. SETTING: A comprehensive rehabilitation hospital. PARTICIPANTS: Forty consecutive stroke patients (21 men, 19 women) with first ischemic stroke who met the inclusion criteria. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Change in motor deficit as evaluated by the Adams Hemispheric Stroke Scale. RESULTS: Stepwise regression analysis indicated that the most significant factors influencing motor recovery were the time elapsed since stroke and muscle tone. CONCLUSIONS: Rehabilitation of stroke patients is more effective in the first months after the event rather than later, considering the significant correlation observed between motor recovery and time elapsed since stroke. Flaccid patients appear to need 3 months or more before reaching the final plateau, because motor recovery occurs later and/or proceeds more slowly, whereas outcomes for spastic patients with spasticity appears to occur in the first months after stroke.  相似文献   
1000.
A condition defined as nonalcoholic fatty liver disease (NAFLD) is frequently found in humans. Deemed as a benign condition until recently, more emphasis is now put on the potential harmful evolution of the inflammatory form, that is, nonalcoholic steatohepatitis (NASH), toward end-stage liver disease. This review highlights the major morphologic and pathophysiological features of NASH. The link between experimental biochemical findings in animal models and clinical and therapeutic approaches in humans is discussed. Once all the other causes of persistent elevation of serum transaminase levels have been excluded, the diagnosis of NASH can be only confirmed by liver histology. Other noninvasive diagnostic tools, however, are being investigated to assess specific subcellular functions and to allow the follow-up of patients at higher risk for major liver dysfunction. A better understanding of various pathogenic aspects of NASH will help in identifying potential therapeutic approaches in these patients.  相似文献   
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