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11.
Nocardia ignorata is a recently described species identified on the basis of a single isolate of unknown origin. Here we describe the epidemiological, phenotypic, and phylogenetic characteristics of this new species, based on five new clinical and soil isolates.  相似文献   
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A quartz crystal microbalance has been used to check the purity of glycerol. The experimental procedure involves no derivatization or other preliminary step except determination of water content. The protocol consists of the direct reading of the frequency of a quartz crystal with one face in contact with an aqueous solution of the glycerol to be tested. The method is inexpensive, simple, rapid, and highly sensitive; diethylene glycol contamination at the 3.61% level could be detected.  相似文献   
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OBJECTIVES: To identify if older adults have equitable access to health services in four major Latin American cities and to determine if the inequities that are found follow the patterns of economic inequality in each of the four nations studied. METHODS: Data from persons age 60 and over in the cities of S?o Paulo, Brazil (n = 2,143); Santiago, Chile (n = 1,301); Mexico City, Mexico (n = 1,247); and Montevideo, Uruguay (n = 1,450) were collected through a collaboration led by the Pan American Health Organization. For our study, three process indicators of access (availability, accessibility, and acceptability) and one indicator of actual health services use (visit to a medical doctor in the past 12 months) were analyzed by wealth quintiles, health insurance type, education, health status, and demographic characteristics. RESULTS: Each of the four cities had a different level of access to care, and those levels of access were only weakly related to per capita national wealth. Given the relatively high level of wealth inequality in Brazil and the lower level in Uruguay, older persons in S?o Paulo had better-than-expected equity in access to care, while older persons in Montevideo had less equity than expected. Inequity in Mexico City was driven primarily by low levels of health insurance coverage. In Santiago, inequity followed socioeconomic status more than it did health insurance. CONCLUSIONS: In the four cities studied, health insurance and the operation of health systems mediate the link between economic inequality and inequitable access to health care. Therefore, special attention needs to be paid to equity of access in health services, independent of differences in economic inequality and national wealth.  相似文献   
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Matrix metalloproteinases (MMPs) are proteolytic enzymes related to a proinflammatory environment in several diseases, including diabetes, which can be activated by reactive nitrogen species. This work aimed to determine MMP-2 and MMP-9 activities and nitration in term placentas from type 2 diabetic patients and verify the hypothesis that peroxynitrites are positive regulators of placental MMP-2 and MMP-9 activities. For this purpose, term placentas from healthy and type 2 diabetic patients were analyzed for MMP-2 and MMP-9 levels and activities, protein nitration, and nitration of MMP-2 and MMP-9. Villous explants were cultured in the presence of peroxynitrites for further evaluation of MMP-2 and MMP-9 activities. We found that MMP-2 and MMP-9 activities were increased in term placentas from diabetic patients. These changes were found even when MMP-2 protein concentrations were diminished and MMP-9 protein concentrations were not changed in the diabetic group. Increased protein nitration and specific nitration of MMP-2 and MMP-9 were found in term placentas from diabetic patients. Peroxynitrites were able to increase the activity of placental MMP-2 and MMP-9. Taken together, this study has shown for first time that peroxynitrites can nitrate and activate MMP-2 and MMP-9 in the placenta, a nitrative pathway possibly related to MMPs overactivity in the placentas from type 2 diabetic patients.  相似文献   
15.
Ts65Dn mice (TS), the most commonly used model of Down syndrome (DS), exhibit phenotypic characteristics of this condition. Both TS mice and DS individuals present cognitive disturbances, age‐related cholinergic degeneration, and increased brain expression of β‐amyloid precursor protein (AβPP). These neurodegenerative processes may contribute to the progressive cognitive decline observed in DS. Melatonin is a pineal indoleamine that has been reported to reduce neurodegenerative processes and improve cognitive deficits in various animal models. In this study, we evaluated the potentially beneficial effects of long‐term melatonin treatment on the cognitive deficits, cholinergic degeneration, and enhanced AβPP and β‐amyloid levels of TS mice. Melatonin was administered for 5 months to 5‐ to 6‐month‐old TS and control (CO) mice. Melatonin treatment improved spatial learning and memory and increased the number of choline acetyltransferase (ChAT)‐positive cells in the medial septum of both TS and CO mice. However, melatonin treatment did not significantly reduce AβPP or β‐amyloid levels in the cortex or the hippocampus of TS mice. Melatonin administration did reduce anxiety in TS mice without inducing sensorimotor alterations, indicating that prolonged treatment with this indoleamine is devoid of noncognitive behavioral side effects (e.g., motor coordination, sensorimotor abilities, or spontaneous activity). Our results suggest that melatonin administration might improve the cognitive abilities of both TS and CO mice, at least partially, by reducing the age‐related degeneration of basal forebrain cholinergic neurons. Thus, chronic melatonin supplementation may be an effective treatment for delaying the age‐related progression of cognitive deterioration found in DS.  相似文献   
16.
The Statement by the Spanish Society of Family and Community Medicine (SemFYC) on access to scientific information, highlights the need for providing digital libraries with certain resources in Autonomous Regions.The primary goal is to study the evidence-based medicine (EBM) coverage that SemFYC recommends regional virtual libraries. The regional health virtual libraries were identified and the access provided to health professionals, Internet presence, remote access and resources were studied.The results suggest there is ample coverage in 8 Autonomous Regions. At the top of the list was, Health Sciences Virtual Library of Navarre, the Balearic Islands Health Sciences Virtual Library, and Virtual Library of the Andalusian Public Health System.The present study needs to be extended to the other biomedical sciences, in order to obtain more accurate results.  相似文献   
17.
Prosthetic valve endocarditis is a major diagnostic challenge in clinical practice, due to the lower sensitivity of the modified Duke criteria and a higher percentage of cases with negative or inconclusive echocardiography results. The delay in establishing medical and surgical treatment increases the morbidity/mortality rate. New imaging techniques and 18F-FDG PET/CT in particular have meant a significant advance in cases of high clinical suspicion and negative or inconclusive echocardiography, increasing the overall sensitivity of the modified Duke criteria.We report the case of a male patient with prosthetic valve endocarditis, where 18F-FDG PET/CT provided the diagnostic key, determining the origin of the endocarditis and avoiding treatment delay.  相似文献   
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