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1.
Farid Saad 《Asian journal of andrology》2015,17(1):58-60
It is no exaggeration to say that our conceptualization of the (patho-) physiological functions of testosterone has undergone a revolutionary development over the last three decades. The traditional thinking was that the biological functions of testosterone were restricted mainly to the area of reproduction and male sexuality. However, scientific research has clearly demonstrated that testosterone is a multi-system hormone serving a wide range of hitherto unsuspected biological functions.In line with this, it will be argued in this contribution that the physiological role of testosterone has been underestimated, while the risks of testosterone administration have been overstated. Space does not permit to elaborate extensively on all new insights of the role of testosterone in the biology of the male. Three areas will be addressed: (1) the role that testosterone can play in body weight management of hypogonadal men; (2) the role of testosterone in inflammatory processes; (3) the strategy required to let patients benefit from the recent insights that testosterone is a multi-system hormone whose use should not be limited to reproductive/sexual medicine. 相似文献
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Rubens Souza de OLIVEIRA Lanna Jamile Corrêa da COSTA Fernanda Atanaena Gon?alves de ANDRADE Wilson UIEDA Luzia Fátima Alves MARTORELLI Ana Paula de Arruda Geraldes KATAOKA Elizabeth Salbé Travassos da ROSA Pedro Fernando da Costa VASCONCELOS Armando de Souza PEREIRA Ant?nio Ismael Barros do CARMO Marcus Emanuel Barroncas FERNANDES 《Revista do Instituto de Medicina Tropical de S?o Paulo》2015,57(6):497-503
The outbreaks of rabies in humans transmitted by Desmodus rotundus in 2004 and 2005,
in the northeast of the Brazilian State of Para, eastern Amazon basin, made this a
priority area for studies on this zoonosis. Given this, the present study provides
data on this phenomenon in an urban context, in order to assess the possible
circulation of the classic rabies virus (RABV) among bat species in Capanema, a town
in the Amazon basin. Bats were collected, in 2011, with mist nets during the wet and
dry seasons. Samples of brain tissue and blood were collected for virological and
serological survey, respectively. None of the 153 brain tissue samples analyzed
tested positive for RABV infection, but 50.34% (95% CI: 45.67-55.01%) of the serum
samples analyzed were seropositive. Artibeus planirostris was the most common
species, with a high percentage of seropositive individuals (52.46%, 95% CI: 52.31
52.60%). Statistically, equal proportions of seropositive results were obtained in
the rainy and dry seasons (c2 = 0.057, d.f. = 1, p = 0.88). Significantly
higher proportions of males (55.96%, 95% CI: 48.96-62.96%) and adults (52.37%, 95%
CI: 47.35-57.39%) were seropositive. While none of the brain tissue samples tested
positive for infection, the high proportion of seropositive specimens indicates that
RABV may be widespread in this urban area. 相似文献
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Susi Elaine Dal''Belo Lorena Rigo Gaspar Patrícia Maria Berardo Gonçalves Maia Campos 《Skin research and technology》2006,12(4):241-246
BACKGROUND/PURPOSE: The polysaccharide-rich composition of Aloe vera extracts (Aloe barbadensis Miller), often used in cosmetic formulations, may impart moisturizing properties to the product. The aim of this study was to evaluate the effect of cosmetic formulations containing different concentrations of freeze-dried Aloe vera extract on skin hydration, after a single and a 1- and 2-week period of application, by using skin bioengineering techniques. METHODS: Stable formulations containing 5% (w/w) of a trilaureth-4 phosphate-based blend were supplemented with 0.10%, 0.25% or 0.50% (w/w) of freeze-dried Aloe vera extract and applied to the volar forearm of 20 female subjects. Skin conditions in terms of the water content of the stratum corneum and of transepidermal water loss (TEWL) (Corneometer CM 825 and Tewameter TM 210) were analysed before and after a single and 1- and 2-week period of daily application. RESULTS: After a single application, only formulations supplemented with 0.25% and 0.50% (w/w) of Aloe vera extract increased the water content of the stratum corneum, while after the 2-week period application, all formulations containing the extract (0.10%, 0.25% and 0.50%) had the same effect, in both cases as compared with the vehicle. TEWL was not modified after a single and after 1- and 2-week period of application, when compared with the vehicle. CONCLUSION: Our results show that freeze-dried Aloe vera extract is a natural effective ingredient for improving skin hydration, possibly through a humectant mechanism. Consequently, it may be used in moisturizing cosmetic formulations and also as a complement in the treatment of dry skin. 相似文献
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In addition to a working knowledge of general complications such as thromboembolism and infective endocarditis, optimal care of the patient with a prosthetic valve requires specific knowledge concerning the characteristics of a given patient's prosthesis. This may need to include the ability to identify the valve roentgenographically when history and records are unavailable. A 53-year-old woman with mitral stenosis secondary to rheumatic heart disease and status post a reported Bjork-Shiley mitral valve (MV) replacement 17 years prior to hospital admission was referred for evaluation of severe hemolytic anemia. Previous cinefluoroscopy in 1986 at the time of a cerebrovascular accident revealed a normally functioning caged disc prosthesis and not the tilting disc of a Bjork-Shiley prosthetic valve. The valve was not further characterized and she continued receiving warfarin therapy until May 1989 when she presented with laboratory findings showing a marked hemolytic anemia with a hemoglobin of 6.5 mg/dl and lactate dehydrogenase (LDH) value of 2100 IU. Echocardiography revealed normal valvular function without evidence of perivalvular leak. The patient was referred for further evaluation with chest roentgenogram at the time of hospital admission revealing a valve configuration characteristic of the Beall model 103/104 series that has been found to manifest progressive disc variance with a high degree of hemolytic anemia (despite normal noninvasive evaluation of MV function), disc tilting with intermittent regurgitation, and catastrophic disc embolization in extreme cases. The precise identification of valvular prosthesis in patients after valve replacement is crucial for optimal management. As in our case, the mere identification of a particular valve may necessitate certain management and therapy based on the natural history of that valve. In the absence of reliable history and/or records, the roentgenographic examination should lead to the precise identification. 相似文献
9.
R C de Oliveira A Gon?alves 《Revista do Instituto de Medicina Tropical de S?o Paulo》1991,33(3):233-239
In Brazil, Public Health specialization courses with the characteristics presently adopted by the National School of Public Health, i.e., short duration and great amplitude, are relatively recent, having started approximately fifteen years ago. In Brasília, nine such courses have been already completed, having, six of them, directive and/or teaching involvement by the authors. Results on a final assessment of one the courses are herewith presented in order to introduce our experience as a contribution to future analogous initiatives. The assessment was applied to a random sample of students, teachers and coordinators, with the objective of identifying positive and negative appreciations about methodological, operational, administrative and institutional aspects. Answers were quite variable, with the highest frequencies scored to field work and to the apprehension on admitting graduates to the Health System. Such aspects deserve final differentiated discussion. 相似文献
10.
Raquel Carreira Ana Duarte Pedro Monteiro Maria Sancha Santos Ana Cristina Rego Catarina R Oliveira Lino M Gon?alves Luís A Providência 《Revista portuguesa de cardiologia》2004,23(11):1447-1455
Ischemia negatively affects mitochondrial function by inducing the mitochondrial permeability transition (MPT). The MPT is triggered by oxidative stress, which occurs in mitochondria during ischemia as a result of diminished antioxidant defenses and increased reactive oxygen species production. It causes mitochondrial dysfunction and can ultimately lead to cell death. Therefore, drugs able to minimize mitochondrial damage induced by ischemia may prove to be clinically effective. We analyzed the effect of carvedilol, a beta-blocker with antioxidant properties, on mitochondrial dysfunction. Carvedilol decreased levels of TBARS (thiobarbituric acid reactive substances), an indicator of oxidative stress, which is consistent with its antioxidant properties. Regarding cell death by apoptosis, although ischemia did increase caspase-8-like activity, there were no changes in caspase-3-like activity, which is activated downstream of caspase-8; this may indicate that the apoptotic cascade is not activated by 60 minutes of ischemia. We conclude that carvedilol protects ischemic mitochondria by preventing oxidative mitochondrial damage, and, by so doing, it may also inhibit the formation of the MPT pore. 相似文献