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Purpose

There is presently an ongoing debate on the relative merits of suggested criteria for spirometric airway obstruction. This study tests the null hypothesis that no superiority exists with the use of fixed ratio (FR) of forced expiratory volume in the first second (FEV1)/forced vital capacity (FVC) < 0.7 versus less than lower limit predicted (LLN) criteria with or without FEV1 <80% predicted in regards to future mortality.

Methods

In 1988–1994 the Third National Health and Nutrition Examination Survey (NHANES III) measured FEV1 and FVC with mortality follow-up data through December 31, 2011. For this survival analysis 7472 persons aged 40 and over with complete data formed the analytic sample.

Results

There were a total of 3554 deaths. Weighted Cox proportional hazards regression revealed an increased hazard ratio in persons with both fixed ratio and lower limit of normal with a low FEV1 (1.79, p < 0.0001), in those with fixed ratio only with a low FEV1 (1.77, p < 0.0001), in those with abnormal fixed ratio only with a normal FEV1 (1.28, p < 0.0001) compared with persons with no airflow obstruction (reference group). These remained significant after adjusting for demographic variables and other confounding variables.

Conclusions

The addition of FEV1 < 80% of predicted increased the prognostic power of the fixed ratio <0.7 and/or below the lower limit of predicted criteria for airway obstruction.  相似文献   
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Aqueous, ethanolic and hexane extracts of the leaves of Nauclea latifolia (Rubiaceae) were assessed for their fasting blood glucose lowering effect in normoglycaemic and streptozotocin - diabetic rats. Wistar strain albino rats were given different doses of the extracts after 18 hrs fast and their blood glucose measured at 0,1,2,4 and 6 hours after treatment. The aqueous and ethanolic extracts significantly lowered the fasting blood glucose levels of the STZ-diabetic rats in a dose-dependent manner. The highest dose administered (400mg/kg) lowered the fasting blood glucose of the diabetic rats by 31.7% (aqueous) and 36.1% (ethanolic) extracts. The aqueous extract did not significantly lower the glucose levels of normoglycaemic rats (maximum 6.6%), nor was any significant decrease seen in the rats administered with the hexane (maximum of 4.0% for normoglycaemic and 2.4% for diabetics) extract. The hypoglycaemic and antihyperglycaemic potentials of the aqueous and ethanolic extracts were comparable to that of glibenclamide (1mg/kg).These results further support the traditional use of the plant in the treatment of diabetes mellitus.  相似文献   
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Spin-lattice relaxation times (T1) have been measured by 13C NMR for poly(vinyl alcohol), poly(vinyl benzoate), poly(vinyl cinnamate) and poly(vinyl acetate) in dimethyl sulfoxide as a function of temperature and concentration. As expected, T1 increases with increasing temperature and decreases with increasing polymer concentration. The influence of the microstructure (tacticity) of the polymers on the relaxation times is negligible. T1 for the methine carbon of the polymer main chain is observed to serve as a measure of the rigidity and/or mobility of the chain. Assuming isotropic motion of the polymer chains, the activation energies for the protonated carbons were determined using the calculated correlation times.  相似文献   
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Berberine is an isoquinoline alkaloid, found in several plants. Diabetes induces erectile dysfunction (ED) via reduction in some hormones and enzymes implicated in sexual function. This study aimed to investigate the role of berberine on crucial biomolecules linked to penile function in diabetic rats. Sixty-three (63) adult male rats were used and distributed into nine groups (each = 7). Group I–IV normal rats administered with citrate buffer (pH 4.5), sildenafil citrate (SD, 5.0 mg/kg), 50 and 100 mg/kg of berberine, respectively, via oral gavage. Rats in groups V–IX were diabetic rat with ED treated with buffer, SD, 50 and 100 mg/kg of berberine, and acarbose (25 mg/kg ACA) respectively. The result revealed that histological architecture in penile tissues were altered in diabetic groups treated with berberine, sildenafil citrate and acarbose when compared to the diabetic control group. Treatment with berberine, increased testosterone, luteinizing hormone and follicle-stimulating hormone in diabetic rat with ED. Also, reduced prolactin level and acetylcholinesterase, angiotensin-1 converting enzyme, adenosine deaminase and arginase activities were observed in berberine treated diabetic rat with ED. Molecular docking analysis revealed that berberine had strong binding affinities for these enzymes. Thus, berberine could represent a potential therapeutic agent for diabetes-induced ED.  相似文献   
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Neoplastic involvement of the pericardium resulting in an effusion and subsequent tamponade is an emergency requiring prompt decompression, generally safely accomplished by subxiphoid pericardiectomy. However, the current case report describes a patient with florid pericardial tamponade who underwent surgical decompression with transient hemodynamic improvement, who then rapidly developed progressive, heart failure and death. This paradoxical response to pericardial decompression, similar to that seen occasionally with pericardiectomy in constrictive pericarditis, may be more frequent than currently appreciated. Its cause may relate to the sudden removal of the chronic external ventricular support from the effusion resulting in ventricular dilatation and failure.  相似文献   
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Antenatal care (ANC) utilization is lower in Nigeria than the African average. We investigated the relationship between wealth and utilization of ANC and also assessed other determinants associated with ANC utilization in Nigeria. Using data of the most recent births within 5 years prior to a 2012 nationally representative survey, we modeled predictors of ANC utilization. Respondents in the wealthiest quintile were over five times (aOR = 5.5 (95% CI: 4.2–7.2) more likely to adequately use ANC. The odds of ANC use were generally lower among the poor and the least educated women living in rural areas who need ANC the most.  相似文献   
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