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91.

Objective

This randomized double-blind clinical trial compared the performance of posterior composite restorations with or without bevel, after 1-year follow-up.

Material and Methods

Thirteen volunteers requiring at least two posterior composite restorations were selected. Twenty-nine cavities were performed, comprising 14 without bevel (butt joint) and 15 with bevel preparation of the enamel cavosurface angle. All cavities were restored with simplified adhesive system (Adper Single Bond) and composite resin (Filtek P60). A halogen light curing unit was used through the study. Restorations were polished immediately. Analysis was carried out at baseline, after 6 months and after 1 year by a calibrated evaluator (Kappa), according to the FDI criteria. Data were statistically analyzed by Mann-Whitney test (p<0.05).

Results

Beveled and non-beveled cavities performed similarly after 1 year follow-up, regarding to fractures and retention, marginal adaptation, postoperative hypersensitivity, recurrence of caries, surface luster and anatomic form. However, for surface and marginal staining, beveled cavities showed significantly better performance (p<0.05) than butt joint restorations.

Conclusions

It was concluded that the restorations were acceptable after 1 year, but restorations placed in cavities with marginal beveling showed less marginal staining than those placed in non-beveled cavities.  相似文献   
92.
Disseminated sporotrichosis occurs in individuals with impaired cellular immunity, such as in cases of neoplasia, transplantation, diabetes, and especially, acquired immunodeficiency syndrome. This report presents a 32-year-old Brazilian human immunodeficiency virus (HIV)-infected patient who developed a protracted condition of disseminated sporotrichosis with endocarditis, bilateral endophthalmitis, and lymphatic involvement. He needed cardiac surgery to replace the mitral valve. Sporothrix brasiliensis isolates were recovered from cultures of subcutaneous nodules and mitral valve fragments. Species identification was based on classical and molecular methods. The patient received amphotericin B for 52 days and subsequently, oral itraconazole. He remains asymptomatic, and he is on maintenance therapy with itraconazole. Despite his positive clinical outcome, he developed bilateral blindness. To our knowledge, this case is the first report of endocarditis and endophthalmitis caused by S. brasiliensis.  相似文献   
93.
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95.
Metals capped with organochalcogenides have attracted considerable interest due to their practical applications, which include catalysis, sensing, and biosensing, due to their optical, magnetic, electrochemical, adhesive, lubrication, and antibacterial properties. There are numerous reports of metals capped with organothiol molecules; however, there are few studies on metals capped with organoselenium or organotellurium. Thus, there is a gap to be filled regarding the properties of organochalcogenide systems which can be improved by replacing sulfur with selenium or tellurium. In the last decade, there has been significant development in the synthesis of selenium and tellurium compounds; however, it is difficult to find commercial applications of these compounds because there are few studies showing the feasibility of their synthesis and their advantages compared to organothiol compounds. Stability against oxidation by molecular oxygen under ambient conditions is one of the properties which can be improved by choosing the correct organochalcogenide; this can confer important advantages for many more suitable applications. This paper reports the successful synthesis and characterization of gold nanoparticles functionalized with organochalcogenide molecules (dibutyl-disulfide, dibutyl-diselenide and dibutyl-ditelluride) and evaluates the oxidation stability of the organochalcogenides. Spherical gold nanoparticles with diameters of 24 nm were capped with organochalcogenides and were investigated using X-ray photoelectron spectroscopy (XPS) to show the improved stability of organoselenium compared with organothiol and organotellurium. The results suggest that the organoselenium is a promising candidate to replace organothiol because of its enhanced stability towards oxidation by molecular oxygen under ambient conditions and its slow oxidation rate. The observed difference in the oxidation processes, as discussed, is also in agreement with theoretical calculations.

This study presents the improved stability against oxidation by molecular oxygen under ambient conditions of organoselenium compared with organothiol, and organotellurium.  相似文献   
96.
AimsTo evaluate the spatio-temporal variables of gait and the isometric muscle strength component of the ankle in patients with peripheral diabetic neuropathy. Also, verify the relationship between these variables and gait parameters.MethodsThis study involved 25 diabetic peripheral neuropathy (DPN) participants (62.4 ± 8.36 years) and 27 age-matched healthy control individuals (64.48 ± 6.21 years). The assessment of the spatio-temporal parameters of gait was performed using an electronic baropodometry treadmill. Prior to the collection data, each participant was instructed to walk on the treadmill in her/his habitual self-selected speed.ResultsDiabetic neuropathy group showed impairment of gait, with a smaller stride and length speed of the cycle, and increased duration of support time. Restricted dorsiflexion mobility and increased plantarflexion mobility were found, with a decrease in muscle strength of the dorsiflexors and plantiflexors. There was a significant relationship between plantiflexor muscle strength and the length and speed of the gait cycle. Also the muscle strengths of the plantiflexors and dorsiflexors, and the range of motion of dorsiflexion were predictors of gait performance.ConclusionsThe ankle, muscle strength and ankle mobility variables could explain changes in gait speed and range of motion in patients with DPN, allowing for the application of preventive strategies.  相似文献   
97.

Background

The aim of this study was to describe the access and factors associated with kidney transplantation for children in different regions of Brazil.

Methods

We analyzed a cohort of 1211 children enrolled on the transplant list from January 2011 to December of 2013. We fitted regression models to investigate factors associated with: (a) undergoing kidney transplantation from a deceased donor, and (b) being removed from the waiting list.

Results

The incidence of transplantation was uneven across regions, with the lowest rate at 0.4 per million age-related population (pmarp) in the Midwest and the highest incidence rate of 8.3 cases pmarp in the South. Children from the North and the Midwest regions had a 3–4 times lower probability of undergoing a deceased donor transplant (p < 0.05). Apart from the geographic region, age of recipients and GDP influenced the outcome. The likelihood of undergoing transplantation was very low in the youngest children in the North and Midwest. The number of transplant centers was not associated with either outcome.

Conclusions

Factors of inequality in transplantation in Brazil are of macroeconomic origin, but there is room to reduce inequalities. Training existing transplant center professionals in the care of children could diminish the discrepancies.
  相似文献   
98.

Introduction

The terminology for female pelvic floor prolapse (POP) should be defined and organized in a clinically-based consensus Report.

Methods

This Report combines the input of members of two International Organizations, the International Urogynecological Association (IUGA) and the International Continence Society (ICS), assisted at intervals by external referees. Appropriate core clinical categories and a sub-classification were developed to give a coding to definitions. An extensive process of fourteen rounds of internal and external review was involved to exhaustively examine each definition, with decision-making by collective opinion (consensus).

Results

A Terminology Report for female POP, encompassing over 230 separate definitions, has been developed. It is clinically-based with the most common diagnoses defined. Clarity and user-friendliness have been key aims to make it interpretable by practitioners and trainees in all the different specialty groups involved in female pelvic floor dysfunction and POP. Female-specific imaging (ultrasound, radiology and MRI) and conservative and surgical managements are major additions and appropriate figures have been included to supplement and clarify the text. Emerging concepts and measurements, in use in the literature and offering further research potential, but requiring further validation, have been included as an appendix. Interval (5–10 year) review is anticipated to keep the document updated and as widely acceptable as possible.

Conclusion

A consensus-based Terminology Report for female POP has been produced to aid clinical practice and research.
  相似文献   
99.
Pregnant women and newborns are at increased risk of vitamin D deficiency. Our objective was to create a global summary of maternal and newborn vitamin D status. We completed a systematic review (1959–2014) and meta‐analysis of studies reporting serum 25‐hydroxyvitamin D [25(OH)D] concentration in maternal and newborn populations. The 95 identified studies were unevenly distributed by World Health Organization (WHO) region: Americas (24), European (33), Eastern Mediterranean (13), South‐East Asian (7), Western Pacific (16) and African (2). Average maternal 25(OH)D concentrations (nmol L?1) by region were 47–65 (Americas), 15–72 (European), 13–60 (Eastern Mediterranean), 20–52 (South‐East Asian), 42–72 (Western Pacific) and 92 (African). Average newborn 25(OH)D concentrations (nmol L?1) were 35–77 (Americas), 20–50 (European), 5–50 (Eastern Mediterranean), 20–22 (South‐East Asian), 32–67 (Western Pacific) and 27–35 (African). The prevalences of 25(OH)D <50 and <25 nmol L?1 by WHO region in pregnant women were: Americas (64%, 9%), European (57%, 23%), Eastern Mediterranean (46%, 79%), South‐East Asian (87%, not available) and Western Pacific (83%, 13%). Among newborns these values were: Americas (30%, 14%), European (73%, 39%), Eastern Mediterranean (60%, not available), South‐East Asian (96%, 45%) and Western Pacific (54%, 14%). By global region, average 25(OH)D concentration varies threefold in pregnant women and newborns, and prevalence of 25(OH)D <25 nmol L?1 varies eightfold in pregnant women and threefold in newborns. Maternal and newborn 25(OH)D concentrations are highly correlated. Addressing vitamin D deficiency in pregnant women and newborns should be a global priority. To protect children from the adverse effects of vitamin D deficiency requires appropriate interventions during both pregnancy and childhood.  相似文献   
100.
The malaria parasite sporozoite stage develops in the mosquito vector and is transmitted to the mammalian host by bite. Sporozoites engage in multiple interactions with vector and host tissue on the journey from their oocyst origin to their final destination inside hepatocytes. Several malaria proteins have been identified that mediate sporozoite interactions with target tissues such as secreted and surface-associated ligands CSP and TRAP, which contain a thrombospondin type 1 repeat (TSR). Recently, we identified thrombospondin-related sporozoite protein (TRSP) in Plasmodium sporozoites, which exhibits a single TSR in its putative extracellular N-terminal region and is highly conserved among Plasmodium species. Here, we show using targeted gene disruption in the rodent malaria model Plasmodium berghei, that lack of TRSP has no effect on the asexual blood stage cycle, parasite transmission to the mosquito, sporozoite development and infection of mosquito salivary glands. However, analysis of TRSP knockout sporozoites in vitro and in vivo indicates that this protein has a significant role in hepatocyte entry and therefore liver infection. Thus, TRSP is an additional TSR-containing malaria parasite protein that is mainly involved in initial infection of the mammalian host.  相似文献   
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