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991.
For confidentiality reasons, US federal death certificate data are incomplete with regards to the dates of birth and death for the decedents, making calculation of total lifetime of a decedent impossible and thus estimation of mortality incidence difficult. This paper proposes the use of natality data and an imputation‐based method to estimate age‐specific mortality incidence rates in the face of this missing information. By utilizing previously determined probabilities of birth, a birth date and death date are imputed for every decedent in the dataset. Thus, the birth cohort of each individual is imputed, and the total on‐study time can be calculated. This idea is implemented in two approaches for estimation of mortality incidence rates. The first is an extension of a person‐time approach, while the second is an extension of a life table approach. Monte Carlo simulations showed that both approaches perform well in comparison to the ideal complete data methods, but that the person‐time method is preferred. An application to Tay–Sachs disease is demonstrated. It is concluded that the imputation methods proposed provide valid estimates of the incidence of death from death certificate data without the need for additional assumptions under which usual mortality rates provide valid estimates.  相似文献   
992.
BackgroundFaculty vitality is the main ingredient to enhance professional education and competence. Enriching the faculty vitality in key domains of teaching, assessing, research, professionalism, and administration is perceived to improve educational environment significantly and enhances the academic performance of learners. Faculty development program (FDP) has been considered as a stand-alone educational pedagogy in fostering knowledge and professional skills of faculty. However, few studies have provided objective reports about the impact of such programs in a healthcare system.MethodsThis research was conducted by selecting data sources of PubMed-Medline, Wiley online library, Cochrane library, Taylor & Francis Online, CINAHL, Springer link, Proquest, ISI Web of knowledge, ScienceDirect, EJS, EBSCO, Blackwell, Emerald and ABI Inform. This search followed a step-wise approach defined by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). A total of 37 studies that explored the impact of FDPs on medical and allied health faculty’s professional development were selected.ResultsThis meta-analysis reported a mean effect size of 0.73 that reflects a significant and positive impact of FDPs in enhancing faculty’s knowledge and professional competence (z-statistics of 4.46 significant at p-value < 0.05) using the random effects model and forest plot.ConclusionThis article reiterates the incorporation of FDPs in all healthcare institutions for improving the academic performance of faculty with resultant enrichment of learners’ knowledge and skills.  相似文献   
993.
Lactogenic hormones from the placenta and pituitary are primarily responsible for the growth and function of the mammary gland during pregnancy and lactation. In the present study we describe the optimal conditions for the measurement of 125I-labeled ovine prolactin binding to mammary gland slices of pregnant and lactating rats. Prolactin binding is saturable (Kd approx. 2.36 · 10?9 M), hormone specific and destroyed by proteases. The hormonal environments of pregnancy and lacation dramatically influence the availability and measurement of prolactin binding sites. Whereas binding consistently appears to be low in mammary glands removed from rats during pregnancy, binding levels rise 7–8-fold shortly after birth and remain high during the 22 days of lactation. However, the removal of the ovaries and gravid uteri at specific times during pregnancy results in prompt 3–6-fold increase in prolactin binding. Elevated levels in potential prolactin binding capacity appear in mammary tissue coincident with the reported rise in serum rat placental lactogen between the eight and eleventh days. We suggest that high levels of this lactogenic hormone promote the appearance of prolactin binding sites during pregnancy and mask the sites such that they are not available for measurement in vitro.  相似文献   
994.
This report describes the relationship between the amount of sodium dodecyl sulfate present in a sample solution and the electrophoretic mobility of the protein-dodecyl sulfate complexes. In order to determine the extent of any conformational changes in the proteins and to establish a correlation between any of these structural changes and the electrophoretic behavior, visible absorption spectra and circular dichroism spectra were obtained for heme proteins in the presence of the same amounts of surfactants as used in electrophoresis.From the results obtained, it is apparent that the amount of sodium dodecyl sulfate present in the sample solution must be taken into consideration when performing a separation. Optimum experimental conditions are chosen for attaining enhanced separation and a maximized linear range of molecular weights of proteins that can be accurately determined.  相似文献   
995.
A competing risk model, accommodating both Type I censoring and random withdrawals, is expanded to incorporate concomitant information by allowing the parameters of the underlying distributions to be a linear function of two covariates. The model is developed for two competing risks, one following a Weibull distribution and the other a Rayleigh distribution, and random withdrawals following a Weibull distribution. A method is developed for testing the equality of the coefficients for a given covariate for each of the competing risks using MLE'.  相似文献   
996.
Purpose: The value of lactate as a screening biomarker in the emergency department is debated. We analysed all unselected patients in the emergency department with serum lactate measured with regard to different outcome parameters.

Material and Methods: In a retrospective single centre study, we analysed all digitalized patient data of a two-week period of all patients ≥18 where a serum lactate was measured. The lactate levels as well as demographic and other laboratory data were correlated in a logistic regression analysis, univariable as well as multivariable, with the outcome parameters.

Results: A total of 1157 patients contacted the emergency department of which 587 were included. The average lactate level was 2,08?mmol/l (SD ±1.51, median 1.73). A total of 313 patients were admitted to hospital, 274 treated as outpatients. Their median lactate levels were 2.0?mmol/l (min/max 0.6–18?mmol/l) and 1.5?mmol/l (min/max 0.5–7.4?mmol/l), respectively. Univariable regression analysis for hospital admission showed an odds ratio of 1756 (p?p?=?0.004). There was no correlation with admission to ICU, length of stay or a relation to a certain diagnostic group.

Conclusions: Screening lactate levels in unselected emergency department patients do not have a clinical relevance yet.  相似文献   
997.
Food consumption is one of the main routes of human exposure to organochlorine pesticide residues (OCPRs). To assess the potential health risks associated with OCPRs contaminants due to freshwater organism consumption, a number of vegetables, prawn, snail, and fish were collected from Khlong 7 (canal), Rangsit agricultural area, Pathum-Thani Province, Thailand. The samples were extracted using a multiresidue extraction method and then analyzed by gas chromatography with microelectron capture detector (μ -ECD). The results show that low concentrations of OCPRs were detected in parts per billion (ppb) levels. Based on a plausible worst-case scenario, the local population could be at risk for cancer due to consumption of fish contaminated by α -, β -HCH, heptachlor, heptachlor epoxide, aldrin, dieldrin, DDD, DDE, and DDT. Likewise, individuals may be at risk from consumption of Lanchester's freshwater prawn Macrobrachium lanchesteri, freshwater snail Filopaludina mertensi, swamp morning-glory Ipomomea aquatica, neptunia Neptunia oleracea, and water lily Nymphaea lotus because these species all contained elevated concentrations of α -, β -HCH, heptachlor, heptachlor epoxide, aldrin, and dieldrin.  相似文献   
998.
Triglyceride (TG)-lowering LPL variants in combination with genetic LDL-C-lowering variants are associated with reduced risk of coronary artery disease (CAD). Genetic variation in the APOA5 gene encoding apolipoprotein A-V also strongly affects TG levels, but the potential clinical impact and underlying mechanisms are yet to be resolved. Here, we aimed to study the effects of APOA5 genetic variation on CAD risk and plasma lipoproteins through factorial genetic association analyses. Using data from 309,780 European-ancestry participants from the UK Biobank, we evaluated the effects of lower TG levels as a result of genetic variation in APOA5 and/or LPL on CAD risk with or without a background of reduced LDL-C. Next, we compared lower TG levels via APOA5 and LPL variation with over 100 lipoprotein measurements in a combined sample from the Netherlands Epidemiology of Obesity study (N = 4,838) and the Oxford Biobank (N = 6,999). We found that lower TG levels due to combined APOA5 and LPL variation and genetically-influenced lower LDL-C levels afforded the largest reduction in CAD risk (odds ratio: 0.78 (0.73–0.82)). Compared to patients with genetically-influenced lower TG via LPL, genetically-influenced lower TG via APOA5 had similar and independent, but notably larger, effects on the lipoprotein profile. Our results suggest that lower TG levels as a result of APOA5 variation have strong beneficial effects on CAD risk and the lipoprotein profile, which suggest apo A-V may be a potential novel therapeutic target for CAD prevention.  相似文献   
999.
After cardiovascular diseases, infectious diseases are the second most common cause of death worldwide. Although these infections are caused mainly by viruses or bacteria, a systematically growing prevalence of human and animal opportunistic fungal infections is noticeable worldwide. More attention is being paid to this problem, especially due to the growing frequency of recalcitrant and recurrent mycoses. The latter are classically divided into superficial, which are the most common type, subcutaneous, and systemic. This work discusses opportunistic fungal pathogens without proven horizontal transmission between different animal species including humans and microsporidia as spore-forming unicellular parasites related to fungi; however, with a yet undetermined taxonomic position. The review also mentions aetiological agents, risk factors, epidemiology, geographical distribution, and finally symptoms characteristic for individual disease entities. This paper provides insight into fungal infections from a global perspective and simultaneously draws attention to emerging pathogens, whose prevalence is continuously increasing. Finally, this work also takes into consideration the correct nomenclature of fungal disease entities and the importance of secondary metabolites in the pathogenesis of fungal infections.  相似文献   
1000.
The interval estimation of the ratio of two binomial proportions based on the score statistic is superior over other methods. Iterative algorithms for calculating the approximate confidence interval have been provided by, e.g., KOOPMAN (1984, Biometrics 40:513–517) and GART and NAM (1988a, Biometrics 44:323–338). This note presents the analytical solutions for upper and lower confidence limits in a closed form and gives examples for numerical illustration. The non-iterative method is generally more desirable than the iterative method.  相似文献   
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