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911.
BACKGROUND: Ureteral stent placement at kidney transplantation may reduce stenosis or leakage (S/L) complication rates. However, stent placement may also increase risk for early urinary tract infection (early UTI; <3 months after transplant) and BK virus allograft nephropathy (BKVAN). In children, the usefulness of stent placement is not well defined. METHODS: We analyzed retrospective data from children transplanted at our center for the three above outcomes in relation to stents. At our center, stent placement decision is driven by surgeon preference. RESULTS: Among 129 transplants from 1996 to 2006, early UTI was seen in 9.3% and S/L in 4.6%. By univariate analyses, stent placement was a significant risk factor for early UTI (P=0.0399) but not protective for S/L (P=0.23). In multivariate analyses, stent placement, human leukocyte antigen match, and bladder augmentation increased the odds ratio for early UTI. Only deceased donor source increased the odds ratio for S/L. In a truncated data set from 1999 to 2006, BKVAN occurred in 9 of 93 (9.6%). Per minute increase in warm ischemia time was the only significant risk factor for BKVAN by both univariate and Cox regression analyses. Stent placement did not improve graft survival (P=0.5726) but required general anesthesia for removal in the operating room, leading to additional cost and potential risk. CONCLUSION: Routine stent placement in children in this era of low urological complication rates and BKVAN needs reevaluation.  相似文献   
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913.
Anonymous screening of lymphoreticular tissues removed during routine surgery has been applied to estimate the UK population prevalence of asymptomatic vCJD prion infection. The retrospective study of Hilton et al (J Pathol 2004; 203: 733-739) found accumulation of abnormal prion protein in three formalin-fixed appendix specimens. This led to an estimated UK prevalence of vCJD infection of ~1 in 4000, which remains the key evidence supporting current risk reduction measures to reduce iatrogenic transmission of vCJD prions in the UK. Confirmatory testing of these positives has been hampered by the inability to perform immunoblotting of formalin-fixed tissue. Animal transmission studies offer the potential for 'gold standard' confirmatory testing but are limited by both transmission barrier effects and known effects of fixation on scrapie prion titre in experimental models. Here we report the effects of fixation on brain and lymphoreticular human vCJD prions and comparative bioassay of two of the three prevalence study formalin-fixed, paraffin-embedded (FFPE) appendix specimens using transgenic mice expressing human prion protein (PrP). While transgenic mice expressing human PrP 129M readily reported vCJD prion infection after inoculation with frozen vCJD brain or appendix, and also FFPE vCJD brain, no infectivity was detected in FFPE vCJD spleen. No prion transmission was observed from either of the FFPE appendix specimens. The absence of detectable infectivity in fixed, known positive vCJD lymphoreticular tissue precludes interpreting negative transmissions from vCJD prevalence study appendix specimens. In this context, the Hilton et al study should continue to inform risk assessment pending the outcome of larger-scale studies on discarded surgical tissues and autopsy samples.  相似文献   
914.
Reading difficulties are both heritable and stable; however, little is known about the etiology of this stability. Results from a preliminary analysis of data from 56 twin pairs who participated in the Colorado Longitudinal Twin Study of Reading Disability (Astrom et al., Twin Res Hum Genet 10:434–439, 2007) suggested that about two-thirds of the proband deficit at follow-up was due to genetic factors that also influenced deficits at their initial assessment. Although our proband sample is now nearly twice as large, it is still relatively small; thus, to increase power, we subjected data from probands, co-twins and their nontwin siblings to a novel extension of DeFries–Fulker analysis (DeFries and Fulker, Behav Genet 15:467–473, 1985; DeFries and Fulker, Acta Genet Med Gemellol, 37, 205–216, 1988). In addition to providing estimates of univariate and bivariate heritability, this analysis facilitates a test of the difference between shared environmental influences for twins versus siblings. Longitudinal composite reading performance scores at 10.6 and 15.5 years of age, on average, were analyzed from 33 MZ and 64 DZ twin pairs in which at least one member of each pair had reading difficulties, and from 44 siblings of the probands. Scores were highly stable (.86 ± .03, across probands, co-twins and siblings) and heritability of the group deficit at initial assessment was .67 ± .22. Longitudinal bivariate heritability was .59 ± .21, suggesting that nearly 60% of the proband reading deficit at follow-up is due to genetic factors that influenced reading difficulties at the initial assessment. However, tests for special twin environmental influences were nonsignificant.  相似文献   
915.
Golfers most frequently report injuries to the low back, nondominant shoulder, and elbow. Injury patterns differ between elite and recreational golfers; professional and elite golfers tend to experience golf injury related to overuse while amateur golfers may experience injury related to adverse swing technique and overuse. Therapeutic interventions should include assessment and treatment of deficiencies in the kinetic chain and professional instruction to modify swing technique. Changes in the swing may include instruction in a more efficient technique or shortening the swing to decrease biomechanical forces affecting the injured area.  相似文献   
916.
Objectives: Examine the relationship between early age at first birth and mental health among women in their fifties.

Methods: Analysis of data on women from a British 1946 birth cohort study and the U.S. Health and Retirement Study birth cohort of 1931–1941.

Results: In both samples a first birth before 21 years, compared to a later first birth, is associated with poorer mental health. The association between early first birth and poorer mental health persists in the British study even after controlling for early socioeconomic status, midlife socioeconomic status and midlife health. In the U.S. sample, the association becomes non-significant after controlling for educational attainment.

Conclusions: Early age at first birth is associated with poorer mental health among women in their fifties in both studies, though the pattern of associations differs.  相似文献   

917.
918.
919.
Cancer screening is recommended for select cancers worldwide. Cancer screening has become increasingly effective and accessible and often increases overall survival. However, the mental health effects of cancer screening, such as its impact on depression, anxiety, and post-traumatic stress disorder, are largely unknown. Conflicting available literature indicates the negative, neutral, and positive mental health effects of cancer screening across cancer types. There are a limited number of randomized controlled trials measuring the mental health effects of cancer screening. Overall, the more negative and life-threatening the screening results, the greater the mental health effects. Screening for cancer without a known precursor, for example, due to family history, can have positive impacts such as decreased worry and increased quality of life. However, receiving a cancer diagnosis often has negative mental effects that increase with the life-threatening potential of malignancy. In this study, we review the existing literature and provide recommendations for future research to determine if and when cancer screening is the best practice.  相似文献   
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