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排序方式: 共有423条查询结果,搜索用时 16 毫秒
1.
Cynthia J. Hines Thomas J. Lentz Lauralynn McKernan Pranav Rane Christine Whittaker 《Journal of occupational and environmental hygiene》2019,16(2):120-128
Bisphenol A is a commercially important chemical used to make polycarbonate plastic, epoxy resins, and other specialty products. Despite an extensive body of in vitro, animal and human observational studies on the effects of exposure to bisphenol A, no authoritative bodies in the U.S. have adopted or recommended occupational exposure limits for bisphenol A. In 2017, the National Institute for Occupational Safety and Health published a Draft process for assigning health-protective occupational exposure bands, i.e., an airborne concentration range, to chemicals lacking an occupational exposure limit. Occupational exposure banding is a systematic process that uses both quantitative and qualitative toxicity information on selected health effect endpoints to assign an occupational exposure band for a chemical. The Draft process proposes three methodological tiers of increasing complexity for assigning an occupational exposure band. We applied Tier 1 (based on the Globally Harmonized System of Classification and Labelling) and Tier 2 (based on authoritative sources/reviews) to assign an occupational exposure band to bisphenol A. Under both Tier 1 and 2, the occupational exposure band for bisphenol A was “E” (<0.01?mg/m3), an assignment based on eye damage. “E” is the lowest exposure concentration range, reserved for chemicals with high potential toxicity. If eye damage was excluded in assigning an air concentration exposure range, then bisphenol A would band as “D” (>0.01 to 0.1?mg/m3) under Tier 1 (based on reproductive toxicity and respiratory/skin sensitization) and under Tier 2 (based on specific target organ toxicity-repeated exposure). In summary, Tiers 1 and 2 gave the same occupational exposure band for bisphenol A when eye damage was included (“E”) or excluded (“D”) as an endpoint. 相似文献
2.
Ankur Patel Pranav Mandovra Tanveer Majeed Roy V Patankar 《Asian journal of endoscopic surgery》2019,12(2):181-184
Tailgut cyst is an uncommon developmental anomaly arising from the embryonic hindgut in the retrorectal space. The patient frequently is asymptomatic or has vague perineal complaints that pose a diagnostic dilemma. Moreover, the patient is often misdiagnosed and therefore mismanaged. MRI is the investigation of choice for diagnosis. After the diagnosis is established, complete surgical excision is required to alleviate patient discomfort and to prevent complications such as infection, malignant transformation, and recurrence. Proper clinical examination and imaging not only establish the accurate diagnosis but also help in determining the best surgical approach for the patient (anterior abdominal, posterior sacral perineal, or combined approach). We hereby report a case of recurrent tailgut cyst managed with a combined anterior laparoscopic and perineal approach. 相似文献
3.
Multiple linear regression is commonly used to test for association between genetic variants and continuous traits and estimate genetic effect sizes. Confounding variables are controlled for by including them as additional covariates. An alternative technique that is increasingly used is to regress out covariates from the raw trait and then perform regression analysis with only the genetic variants included as predictors. In the case of single-variant analysis, this adjusted trait regression (ATR) technique is known to be less powerful than the traditional technique when the genetic variant is correlated with the covariates We extend previous results for single-variant tests by deriving exact relationships between the single-variant score, Wald, likelihood-ratio, and F test statistics and their ATR analogs. We also derive the asymptotic power of ATR analogs of the multiple-variant score and burden tests. We show that the maximum power loss of the ATR analog of the multiple-variant score test is completely characterized by the canonical correlations between the set of genetic variants and the set of covariates. Further, we show that for both single- and multiple-variant tests, the power loss for ATR analogs increases with increasing stringency of Type 1 error control () and increasing correlation (or canonical correlations) between the genetic variant (or multiple variants) and covariates. We recommend using ATR only when maximum canonical correlation between variants and covariates is low, as is typically true. 相似文献
4.
Pranav Jani Krista Lowe Murray Hinder Claire Galea Daphne D’Çruz Nadia Badawi Mark Tracy 《Vox sanguinis》2020,115(8):712-721
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Simon Hsu Dena E. Rifkin Michael H. Criqui Natalie C. Suder Pranav Garimella Charles Ginsberg Antoinette M. Marasco Belinda J. McQuaide Emma J. Barinas-Mitchell Matthew A. Allison Christina L. Wassel Joachim H. Ix 《Journal of vascular surgery》2018,67(6):1855-1863.e1
Background
Chronic kidney disease (CKD) is strongly associated with peripheral artery disease (PAD). Detection of subclinical PAD may allow early interventions for or prevention of PAD in persons with CKD. Whether the presence of atherosclerotic plaque and femoral intima-media thickness (IMT) are associated with kidney function is unknown.Methods
We performed a cross-sectional observational study of 1029 community-living adults. We measured superficial and common femoral artery IMT and atherosclerotic plaque presence by ultrasound. Estimated glomerular filtration rate (eGFR; continuous) and eGFR <60 mL/min/1.73 m2 (binary) were evaluated as outcomes.Results
Mean age was 70 ± 10 years, mean eGFR was 78 ± 17 mL/min/1.73 m2, and 156 (15%) individuals had eGFR <60 mL/min/1.73 m2; 260 (25%) had femoral artery plaque. In models adjusted for demographics and cardiovascular risk factors, individuals with femoral artery plaque had mean eGFR approximately 3.0 (95% confidence interval, ?5.3 to ?0.8) mL/min/1.73 m2 lower than those without plaque (P < .01). The presence of plaque was also associated with a 1.7-fold higher odds of eGFR <60 mL/min/1.73 m2 (95% confidence interval, 1.1-2.8; P < .02). Associations were similar in persons with normal ankle-brachial index. The directions of associations were similar for femoral IMT measures with eGFR and CKD but were rendered no longer statistically significant with adjustment for demographic variables and cardiovascular disease risk factors.Conclusions
Femoral artery plaque is significantly associated with CKD prevalence in community-living individuals, even among those with normal ankle-brachial index. Femoral artery ultrasound may allow evaluation of relationships and risk factors linking PAD and kidney disease earlier in its course. 相似文献10.