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991.
Cloning of cDNA encoding steroid 11 beta-hydroxylase (P450c11).   总被引:6,自引:3,他引:6       下载免费PDF全文
We have isolated bovine and human adrenal cDNA clones encoding the adrenal cytochrome P-450 specific for 11 beta-hydroxylation (P450c11). A bovine adrenal cDNA library constructed in the bacteriophage lambda vector gt10 was probed with a previously isolated cDNA clone corresponding to part of the 3' untranslated region of the 4.2-kilobase (kb) mRNA encoding P450c11. Several clones with 3.2-kb cDNA inserts were isolated. Sequence analysis showed that they overlapped the original probe by 300 base pairs (bp). Combined cDNA and RNA sequence data demonstrated a continuous open reading frame of 1509 bases. P450c11 is predicted to contain 479 amino acid residues in the mature protein in addition to a 24-residue amino-terminal mitochondrial signal sequence. A bovine clone was used to isolate a homologous clone with a 3.5-kb insert from a human adrenal cDNA library. A region of 1100 bp was 81% homologous to 769 bp of the coding sequence of the bovine cDNA except for a 400-bp segment presumed to be an unprocessed intron. Hybridization of the human cDNA to DNA from a panel of human-rodent somatic cell hybrid lines and in situ hybridization to metaphase spreads of human chromosomes localized the gene to the middle of the long arm of chromosome 8. These data should be useful in developing reagents for heterozygote detection and prenatal diagnosis of 11 beta-hydroxylase deficiency, the second most frequent cause of congenital adrenal hyperplasia.  相似文献   
992.

Background

This article examines the incidence of venous thromboembolism (VTE) in combat wounded, identifies risk factors for pulmonary embolism (PE), and compares the rate of PE in combat with previously reported civilian data.

Methods

A retrospective review was performed of all U.S. military combat casualties in Operation Enduring Freedom and Operation Iraqi Freedom with a VTE recorded in the Department of Defense Trauma Registry from September 2001 to July 2011. The Military Amputation Database of all U.S. military amputations during the same 10-y period was also reviewed. Demographic data, injury characteristics, and outcomes were evaluated.

Results

Among 26,634 subjects, 587 (2.2%) had a VTE. This number included 270 subjects (1.0%) with deep venous thrombosis (DVT), 223 (0.8%) with PE, and 94 (0.4%) with both DVT and PE. Lower extremity amputation was independently associated with PE (odds ratio [OR], 1.70; 95% confidence interval [CI], 1.07–2.69). A total of 1003 subjects suffered a lower extremity amputation, with 174 (17%) having a VTE. Of these, 75 subjects (7.5%) were having DVT, 70 (7.0%) were having PE, and 29 (2.9%) were found to have both a DVT and a PE. Risk factors found to be independently associated with VTE in amputees were multiple amputations (OR, 2; 95% CI, 1.35–3.42) and above the knee amputation (OR, 2.11; 95% CI, 1.3–3.32).

Conclusions

Combat wounded are at a high risk for thromboembolic complications with the highest risk associated with multiple or above the knee amputations.  相似文献   
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BackgroundChlamydia trachomatis is the most commonly diagnosed bacterial sexually transmitted infection in Britain. Present standards specify treatment within 14 days of testing positive; point-of-care testing (POCT) can eliminate this delay and potentially reduce loss to follow-up; its greater convenience might increase testing. 90-min nucleic acid amplification tests are the best available POCTs for chlamydia, with alternatives under development. However, cost-effectiveness depends on cost-per-test, sensitivity and specificity, and the effect of POCT on transmission.MethodsWe developed a user-friendly web-based method, based on a transmission-dynamic model for chlamydia, to assess the epidemiological impact and cost-effectiveness of introducing POCT in different local settings. The model uses behavioural and prevalence data from the National Survey of Sexual Attitudes and Lifestyles, and Public Health England surveillance data; these data inform on local-level variation, which is represented by sampling parameter values from within their ranges of uncertainty and selecting parameter sets that reproduce local coverage and diagnosis rates. The user can select different local settings, and vary sensitivity and specificity for the tests, specify costs (fixed and unit costs, including staff time), and then assess the effect of introducing POCT in different clinical services by comparison with a situation with no POCT. In the model, presumptive treatment is represented, which we expect to be reduced with the introduction of POCT because test results would be rapidly available to guide treatment.FindingsChanges in numbers of infections and diagnoses occurring under different scenarios (including conventional testing) were estimated, with uncertainty ranges, allowing calculation of total costs, and cost per infection (and serious sequelae) averted, while accommodating the considerable variation in chlamydia testing coverage, positivity, and diagnosis rates. Potential changes in sexual behaviour between test and treatment could determine the relative contribution of increased treatment rates and reduced treatment delay to the reduction in prevalence as a consequence of POCT.InterpretationThe effect of POCT was dependent on both the test performance characteristics and the assumptions about the implementation of the test across local services. Exploration of many uncertainties surrounding chlamydia epidemiology and screening implementation is possible with this model. This method can complement local and national knowledge, and contribute to local-level management of chlamydia infection.FundingInnovate UK (Technology Strategy Board), UK Medical Research Council, and the National Institute for Health Research. The Electronic Self-Testing Instruments for Sexually Transmitted Infection (eSTI2) Consortium eSTI2 is Funded under the UKCRC Translational Infection Research (TIR) Initiative supported by the Medical Research Council (Grant Number G0901608) with contributions to the Grant from the Biotechnology and Biological Sciences Research Council, the National Institute for Health Research on behalf of the Department of Health, the Chief Scientist Office of the Scottish Government Health Directorates, and the Wellcome Trust  相似文献   
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Children with sickle cell anemia have a higher‐than‐expected prevalence of poor educational attainment. We test two key hypotheses about educational attainment among students with sickle cell anemia, as measured by grade retention and use of special education services: (1) lower household per capita income is associated with lower educational attainment; (2) the presence of a silent cerebral infarct is associated with lower educational attainment. We conducted a multicenter, cross‐sectional study of cases from 22 U.S. sites included in the Silent Infarct Transfusion Trial. During screening, parents completed a questionnaire that included sociodemographic information and details of their child's academic status. Of 835 students, 670 were evaluable; 536 had data on all covariates and were used for analysis. The students' mean age was 9.4 years (range: 5–15) with 52.2% male; 17.5% of students were retained one grade level and 18.3% received special education services. A multiple variable logistic regression model identified that lower household per capita income (odds ratio [OR] of quartile 1 = 6.36, OR of quartile 2 = 4.7, OR of quartile 3 = 3.87; P = 0.001 for linear trend), age (OR = 1.3; P < 0.001), and male gender (OR, 2.2; P = 0.001) were associated with grade retention; silent cerebral infarct (P = 0.31) and painful episodes (P = 0.60) were not. Among students with sickle cell anemia, household per capita income is associated with grade retention, whereas the presence of a silent cerebral infarct is not. Future educational interventions will need to address both the medical and socioeconomic issues that affect students with sickle cell anemia. Am. J. Hematol. 89:E188–E192, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
996.
Women and men share similar as well as different strategies in developing their spirituality as part of their overall 12-Step experience. Special attention is paid to gender differences to account for a variety of spiritual experiences in recovery. The language and use of metaphors as women and men work the 12 Steps in achieving a “spiritual awakening” is explored, recognizing the predominantly male ethos of Alcoholics Anonymous since its inception. The influence of age in expressions of spirituality, distinguishing between young adults, middle-age adults, and older adults, is referenced. Need for further understanding of gender differences, with a focus on the spiritual dimensions of recovery, is recommended.  相似文献   
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