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排序方式: 共有6615条查询结果,搜索用时 15 毫秒
91.
92.
Janie Canty-Mitchell Joan K. Austin Susan M. Perkins Rong Amy Qi Nancy Swigonski 《Children's Health Care》2005,34(1):1-18
Our objective was to examine health-related quality of life (HRQOL) in publicly insured children with special health care needs (CSHCN). Data were obtained from 183 caregivers of CSHCN (M = 10 years; 54% African American) in urban health clinics. CSHCN had poorer physical and psychosocial HRQOL than children in a normative sample. In regression analysis, children who had more health problems and more health visits in the previous 12 months had poorer physical HRQOL. Poorer psychosocial HRQOL was associated with more health problems and urban life stressors. Implications for practice and policy are discussed. 相似文献
93.
94.
Austin PN 《Air medical journal》2000,19(3):90-97
Air medical personnel in the United States have used neuromuscular blocking agents to facilitate endotracheal intubation in the field for more than a decade. This literature review examines 15 studies to investigate their experience and explores the following specific areas: the intubation success rate in patients who did or did not receive these agents, the intubation success rate of air medical personnel before and after they incorporated these agents into their practice, the neuromuscular blocking agents and adjunct medications used by air medical personnel, and the disposition of patients who could not be intubated after an agent was given. The data suggest that, overall, air medical personnel use these agents safely and effectively. Suggestions are offered for future studies, including examining ground time when agents are used to facilitate intubation, complications of their use in this setting, and the use of simulators to train personnel in the administration of these medications. 相似文献
95.
Austin JW 《The Journal of extra-corporeal technology》2000,32(1):49-53
Multiple variables must be analyzed during cardiopulmonary bypass in order to judge the adequacy of perfusion. Variables when viewed singly can be confusing and lead to inaccurate representation of the physiological status of the patient. Communication between the perfusionist and members of the surgical team requires accuracy and complete presentation of pertinent data. Toward this goal of improving the assimilation and processing of information during cardiopulmonary bypass, a multivariable computer-aided "Heads-up Display" (HUD) was developed. Modern jet pilots use heads-up display for rapid assimilation of information when making judgments about the performance of their aircraft and weapons systems. Heads-up display is an electronically generated display that is superimposed upon a pilot's forward field of view. An analogy between a jet pilot and a perfusionist can be made. A geometric form, a hexagon, is used as part of the heads-up display for cardiopulmonary bypass (CPB-HUD). The polygon represents a performance evaluation graph. Each of the six "spokes of a wheel" represents a physiological parameter. The represented variables are: cardiac index, peripheral vascular resistance, hematocrit, dynamic operating blood level, venous saturation, and mean arterial pressure. The perfusionist inputs target values. Target values are then compared to actual values and expressed as a percentage. If all targeted values are achieved, the graphical representation is a hexagon. The surgical team rapidly recognizes abnormal patterns that are outside individual target values. They include, but are not limited to, patterns of: vasoconstriction, vasodilatation, hypovolemia, decreased oxygen carrying capacity, and several others. The CPB-HUD has proved to be of value for planning, real time evaluation, retrospective analysis of cardiopulmonary bypass benchmark data, and as an aid in the teaching of new personnel concerned with cardiopulmonary bypass. 相似文献
96.
Differences in survival by histologic type of pancreatic cancer. 总被引:3,自引:0,他引:3
Megan Dann Fesinmeyer Melissa A Austin Christopher I Li Anneclaire J De Roos Deborah J Bowen 《Cancer epidemiology, biomarkers & prevention》2005,14(7):1766-1773
OBJECTIVE: Although pancreatic cancer has an extremely high case fatality rate, little is known about differences in mortality by histologic types. We examined median survival and risk of mortality for endocrine pancreatic tumors and two types of exocrine tumors, adenocarcinomas, and mucinous tumors. METHOD: This analysis included 35,276 pancreatic cancer cases reported to the nine population-based cancer registries participating in the Surveillance, Epidemiology, and End Results program from 1973 to 2000. Survival among cases with pancreatic adenocarcinomas, mucinous tumors, and endocrine tumors were compared using Kaplan-Meier plots. Comparative risks of mortality were evaluated using multivariate adjusted Cox regression models. RESULTS: Endocrine pancreatic cancer cases had a median survival of 27 months compared with a median survival of 4 months for adenocarcinoma and mucinous tumor cases. Compared with adenocarcinoma cases, endocrine tumor cases had a 0.28-fold lower risk of mortality [95% confidence interval (95% CI), 0.26-0.30], and mucinous tumor cases had a 0.88-fold lower risk (95% CI, 0.84-0.91). These results were similar for men and women. Within histologic types, advanced tumor stage, older diagnosis age, surgery, and Black race were associated with increased risks of mortality, whereas female sex and more recent year of diagnosis were associated with decreased risks. CONCLUSION: This study confirms the clinical observation that patients with endocrine pancreatic cancer survive longer than patients with exocrine tumors. A better understanding of these differences could contribute to identifying the underlying causes of pancreatic cancer and to improving survival rates across all histologic types. 相似文献
97.
R. Austin Hicklin Linda Eisenhart Nicole Richetelli Meredith D. Miller Peter Belcastro Ted M. Burkes Connie L. Parks Michael A. Smith JoAnn Buscaglia Eugene M. Peters Rebecca Schwartz Perlman Jocelyn V. Abonamah Brian A. Eckenrode 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(32)
Forensic handwriting examination involves the comparison of writing samples by forensic document examiners (FDEs) to determine whether or not they were written by the same person. Here we report the results of a large-scale study conducted to assess the accuracy and reliability of handwriting comparison conclusions. Eighty-six practicing FDEs each conducted up to 100 handwriting comparisons, resulting in 7,196 conclusions on 180 distinct comparison sets, using a five-level conclusion scale. Erroneous “written by” conclusions (false positives) were reached in 3.1% of the nonmated comparisons, while 1.1% of the mated comparisons yielded erroneous “not written by” conclusions (false negatives). False positive rates were markedly higher for nonmated samples written by twins (8.7%) compared to nontwins (2.5%). Notable associations between training and performance were observed: FDEs with less than 2 y of formal training generally had higher error rates, but they also had higher true positive and true negative rates because they tended to provide more definitive conclusions; FDEs with at least 2 y of formal training were less likely to make definitive conclusions, but those definitive conclusions they made were more likely to be correct (higher positive predictive and negative predictive values). We did not observe any association between writing style (cursive vs. printing) and rates of errors or incorrect conclusions. This report also provides details on the repeatability and reproducibility of conclusions, and reports how conclusions are affected by the quantity of writing and the similarity of content.Forensic science is under scrutiny, particularly for pattern-based disciplines in which source conclusions are reported. The National Research Council report Strengthening Forensic Science in the United States: A Path Forward (1) stated that “The scientific basis for handwriting comparisons needs to be strengthened” and noted that “there has been only limited research to quantify the reliability and replicability of the practices used by trained document examiners.” The President’s Council of Advisors on Science and Technology (PCAST) report Forensic Science in Criminal Courts: Ensuring Scientific Validity of Feature-Comparison Methods (2) expressed concerns regarding the validity and reliability of conclusions made by forensic examiners, and called for empirical testing: “The only way to establish the scientific validity and degree of reliability of a subjective forensic feature-comparison method—that is, one involving significant human judgment—is to test it empirically by seeing how often examiners actually get the right answer. Such an empirical test of a subjective forensic feature-comparison method is referred to as a ‘black-box test.’” The National Commission on Forensic Science also called for such testing (3). Although the accuracy and reliability of conclusions made by forensic document examiners (FDEs) have been the focus of multiple studies over the years (4–10), the designs of those studies are notably different from this study (and from PCAST’s recommendations), and therefore the resulting rates are not directly comparable (in particular, when comparing open-set to closed-set studies, comparing studies based on one-to-one vs. one-to-many examinations, and comparing studies that use notably different conclusion scales; see SI Appendix, Appendix B for a summary).This study was conducted to provide data that can be used to assess the scientific validity of handwriting comparisons, for use by policy makers, laboratory managers, the legal community, and FDEs. This study follows the approach used in the previous FBI Laboratory–Noblis latent print black box study (11) and later recommended by the PCAST report. The design utilizes open-set, one-to-one document comparisons to evaluate the conclusions reached by practicing FDEs when comparing writing samples selected to be broadly comparable to casework. The primary purposes of the study are to measure the accuracy of conclusions by FDEs when comparing handwriting samples and to assess reliability by measuring the reproducibility (interexaminer variability) and repeatability (intraexaminer variability) of those conclusions. Secondary purposes include reporting any associations between the accuracy of the decisions in this study, factors related to the participants (such as training or experience), and factors related to the samples (such as quantity of writing, comparability of content, limitations, or style of writing). 相似文献
98.
Erin C. Strumpf Nichole Austin Ariella Lang Shelley Derksen James Bolton Marni Brownell Patricia Gregory Dan Chateau Maureen Heaman 《Health services research》2022,57(4):786
ObjectiveTo evaluate the effects of early pregnancy loss on subsequent health care use and costs.Data SourcesLinked administrative health databases from Manitoba, Canada.Study DesignThis was a population‐based cohort study. The exposure of interest was first recorded ectopic pregnancy or miscarriage (EPM). Outcomes included visits to all ambulatory care providers, family physicians (FPs), specialists, and hospitals, as well as the costs associated with these visits. We also assessed the impact of EPM on a global measure of health service utilization and the incidence and costs of psychotropic medications.Data Collection/Extraction MethodsWe identified women who experienced their first recorded loss (EPM) from 2003–2012 and created a propensity score model to match these women to women who experienced a live birth, with outcome measures available through 31 December 2014. We used a difference in differences approach with multivariable negative binomial models and generalized estimating equations (GEE) to assess the impact of EPM on the aforementioned health care utilization indicators.Principal FindingsEPM was associated with a short‐term increase in visits to, and costs associated with, certain ambulatory care providers. These findings were driven in large part by increased visits/costs to FPs (rate difference [RD]: $19.92 [95% CI: $16.33, $23.51]) and obstetrician‐gynecologists (OB‐GYNs) (RD $9.41 [95% CI: $8.42, $10.40]) in the year immediately following the loss, excluding care associated with the loss itself. We also detected an increase in hospital stays and costs and a decrease in the use of psychotropic medications relative to matched controls.ConclusionPregnancy loss may lead to subsequent increases in certain types of health care utilization. While the absolute costs associated with post‐EPM care are relatively small, the observed patterns of service utilization are informative for providers and policy makers seeking to support women following a loss. 相似文献
99.
Wingo PA Austin H Marchbanks PA Whiteman MK Hsia J Mandel MG Peterson HB Ory HW 《Obstetrics and gynecology》2007,110(4):793-800
OBJECTIVE: To examine the relationship between the use of oral contraceptives and the risk of death from breast cancer. METHODS: We used interview data from the Cancer and Steroid Hormone Study, linked to cancer registry data from the Surveillance, Epidemiology, and End Results Program, to examine the 15-year survival and prior use of oral contraceptives among 4,292 women aged 20 to 54 years when diagnosed with breast cancer from December 1, 1980, to December 31, 1982. Cox proportional hazard models were used to estimate the relative rate of death from breast cancer by oral contraceptive use. RESULTS: Duration of oral contraceptive use, time since first use, age at first use, and use of specific pill formulations were not associated with survival. For time since last use, the risk of death from breast cancer decreased significantly with increasing time since last use of oral contraceptives, but a consistent gradient effect was not observed. Adjusted hazard ratios ranged from 0.86 to 1.41 and were 1.00 or less for all recency categories except during 13 to 24 months before diagnosis; none was statistically significant. Women who were currently using oral contraceptives had an adjusted hazard ratio of 0.90 (0.68, 1.19). CONCLUSION: Overall, oral contraceptive use had neither a harmful nor a beneficial effect on breast cancer mortality. The differences between pill users and nonusers were slight, and the risk estimates were usually reduced with confidence limits that nearly always included 1.0. 相似文献
100.
Role of antibiotic therapy for bacterial vaginosis and intermediate flora in pregnancy 总被引:1,自引:0,他引:1
Ugwumadu A 《Best practice & research. Clinical obstetrics & gynaecology》2007,21(3):391-402
Bacterial vaginosis and intermediate flora are associated with late miscarriage and preterm delivery. The mechanisms involved are not yet fully understood. Clinical trials of antibiotic therapy to reduce these complications have yielded conflicting results. These trials, however, were conducted in mixed populations of pregnant women with variable risk profiles for preterm delivery. Furthermore, investigators used different criteria for diagnosis, treated with different antibiotics at different doses and via different routes, and initiated treatment at different gestational ages. Over 80% of pregnant women with abnormal vaginal flora have a good outcome, and in some populations the presence of bacterial vaginosis is not associated with preterm delivery, suggesting that other host factors may modify the risk. Recent studies have examined the roles of genetic regulation of host immune response, bacterial pathogenic factors, and enzymes in the vagina, and how these factors interact to drive a given outcome. These markers have the potential to better define the women at maximal risk and therefore guide future interventions. This chapter aims to appraise the current state of treatment of abnormal vaginal flora in pregnancy and suggest appropriate management based on the available evidence. 相似文献