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61.
Despite repeated findings of abnormal corpus callosum structure in autism, the developmental trajectories of corpus callosum growth in the disorder have not yet been reported. In this study, we examined corpus callosum size from a developmental perspective across a 30-year age range in a large cross-sectional sample of individuals with autism compared to a typically developing sample. Midsagittal corpus callosum area and the 7 Witelson subregions were examined in 68 males with autism (mean age 14.1 years; range 3–36 years) and 47 males with typical development (mean age 15.3 years; range 4–29 years). Controlling for total brain volume, increased variability in total corpus callosum area was found in autism. In autism, increased midsagittal areas were associated with reduced severity of autism behaviors, higher intelligence, and faster speed of processing (p = 0.003, p = 0.011, p = 0.013, respectively). A trend toward group differences in isthmus development was found (p = 0.029, uncorrected). These results suggest that individuals with autism benefit functionally from increased corpus callosum area. Our cross-sectional examination also shows potential maturational abnormalities in autism, a finding that should be examined further with longitudinal datasets.  相似文献   
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Background

Multiple studies have documented a significant decrease in the general surgery workforce in the United States, both rural and urban, for the past 3 decades. This 11-year study evaluates the Texas general surgery workforce at both the state and local level in 2002 and 2012.

Methods

Data were obtained from the Texas Medical Board, the United States Census Bureau/Texas State Library and Archives Commission, and the Texas Department of State Health Services for 2002 and 2012. A benchmark target of 7 general surgeons per 100,000 population was used.

Results

During the study period, the Texas population increased 21%, and actively practicing physicians increased 44%. All surgical specialists increased by 26%. General surgeons increased 4%; however, the number of general surgeons per 100,000 population decreased 14% (from 6.7 to 5.8/105). Using the total Texas population for 2012, an additional 329 general surgeons are needed by benchmark standards. However, when analyzed by individual county population, 449 additional general surgeons are needed in the individual counties. These effects were greater in the nonmetropolitan areas of Texas where per capita general surgeons decreased by 21%.

Conclusions

The absolute increase in Texas general surgeons over the past decade has not kept pace with an increase in the Texas population. The general surgery workforce deficit based on the Texas state population underestimates the local workforce shortage, particularly in the nonmetropolitan areas of Texas.  相似文献   
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BACKGROUND: Hyperthyroidism has been associated with liver function abnormalities; however, cholestasis as the presenting feature of adolescent Graves' disease has not been previously reported. PATIENT SUMMARY: The patient was a 17-year-old girl who presented with severe cholestasis and was found to have Graves' disease. She also had a positive hepatitis A immunoglobulin M antibody but her clinical course, the liver histopathology, and her mildly elevated transaminases indicated that the acute hepatitis A infection was not dominant at the time of presentation with severe cholestasis. Other causes of cholestasis, including congestive heart failure, autoimmune hepatitis, and viral infection, were excluded. Treatment with methimazole resolved the hyperthyroidism, and the cholestasis improved, as well. CONCLUSION: Severe cholestasis is a rare presenting feature of Graves' disease. With careful monitoring, methimazole can be used to treat the hyperthyroidism in the setting of cholestasis.  相似文献   
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Cash payments to improve health outcomes have been used for many years; however, their use for HIV prevention is new and the impact not yet well understood. We provide a brief background on the rationale behind using cash to improve health outcomes, review current studies completed or underway using cash for prevention of sexual transmission of HIV, and outline some key considerations on the use of cash payments to prevent HIV infections. We searched the literature for studies that implemented cash transfer programs and measured HIV or HIV-related outcomes. We identified 16 studies meeting our criteria; 10 are completed. The majority of studies have been conducted with adolescents in developing countries and payments are focused on addressing structural risk factors such as poverty. Most have seen reductions in sexual behavior and one large trial has documented a difference in HIV prevalence between young women getting cash transfers and those not. Cash transfer programs focused on changing risky sexual behaviors to reduce HIV risk suggest promise. The context in which programs are situated, the purpose of the cash transfer, and the population will all affect the impact of such programs; ongoing RCTs with HIV incidence endpoints will shed more light on the efficacy of cash payments as strategy for HIV prevention.  相似文献   
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