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991.
Forty-eight female detoxified alcoholics and 36 female nonalcoholic controls were administered a short computerized neuropsychological test battery; accuracy and speed were assessed for each item. The accuracy and speed scores were used to create summary efficiency ratios (accuracy/speed) for each test. Alcoholics had significantly lower efficiency ratios than controls on each of the tests, and this deficit was maintained across instructional conditions (emphasizing speed, accuracy, or speed and accuracy equally) and level of task difficulty. In addition, alcoholics and controls manifested similar types of relationships between response speed and correctness of the response, with these relationships varying as a function of type of task. The results of this study illustrate the benefits of including speed of response as a performance variable, and provide further support for the use of efficiency as a measure sensitive to alcoholic neuropsychological impairment. 相似文献
992.
G A Rogers S M Parsons D C Anderson L M Nilsson B A Bahr W D Kornreich R Kaufman R S Jacobs B Kirtman 《Journal of medicinal chemistry》1989,32(6):1217-1230
Eighty-four analogues and derivatives of the acetylcholine-storage-blocking drug trans-2-(4-phenylpiperidino)-cyclohexanol (vesamicol) were synthesized, and their potencies were evaluated with the acetylcholine active-transport assay utilizing purified synaptic vesicles from Torpedo electric organ. The parent drug exhibits enantioselectivity, with (-)-vesamicol being 25-fold more potent than (+)-vesamicol. The atomic structure and absolute configuration of (+)-vesamicol were determined by X-ray crystallography. The absolute configuration of (-)-vesamicol is 1R,2R. Structure-activity evidence indicates that (-)-vesamicol does not act as an acetylcholine analogue. Alterations to all three rings can have large effects on potency. Unexpectedly, analogues locking the alcohol and ammonium groups trans-diequatorial or trans-diaxial both exhibit good potency. A potent benzovesamicol family has been discovered that is suitable for facile elaboration of the sort useful in affinity labeling and affinity chromatography applications. A good correlation was found between potencies as assessed by the acetylcholine transport assay and LD50 values in mouse. 相似文献
993.
Systemically administered 4-S-cysteaminylphenol (4-S-CAP) and N-acetyl-4-S-CAP inhibited the growth of xenografts of a human melanoma cell line but not of an ovarian tumour cell line. No selective cytotoxicity for melanoma cells was observed in culture, however. Further study of the in vitro mechanism of 4-S-CAP toxicity showed minimal inhibition of tyrosinase activity or DNA, RNA and protein synthesis, and there was no phase-specific arrest of the cell cycle. However, expression of an 80 kD melanosomal antigen was decreased. Cytotoxicity of 4-S-CAP in culture was decreased by simultaneous treatment with a monoamine oxidase inhibitor. An affinity column prepared from 4-S-CAP retained several proteins from a melanoma cell lysate. One protein, found also in HeLa cells, was identified by N-terminal sequencing as protein disulphide isomerase, a molecule which has multiple roles in the modification of secretory proteins. These results identify a protein target for 4-S-CAP as one possible mechanism of cytotoxicity. 相似文献
994.
Urinary retention in men after total hip arthroplasty 总被引:1,自引:0,他引:1
T R Redfern D G Machin K F Parsons R Owen 《The Journal of bone and joint surgery. American volume》1986,68(9):1435-1438
A prospective study of sixty-four men was conducted before they underwent a total hip arthroplasty to try to identify the factors that are predictive of postoperative urinary retention. Although neither the urological history nor the physical examination provided information that was helpful in accurately identifying the patients who were at risk, those whose peak urinary flow rate was less than seventeen milliliters per second did have a statistically significant likelihood of the development of urinary retention. A system of management that we hope will reduce the incidence of this complication is proposed. 相似文献
995.
Min J. Song Gerald Kornatowski Donald F. Parsons Murray Vernon King 《Cancer investigation》1987,5(5):429-441
A new method for detecting bloodborne TMT-081 rat mammary tumor cells in buffy coat has revealed dose-dependent variations in the latency period after inoculation of tumor cells, the concentration of circulating tumor cells, and the incidence of metastases. Cells isolated from buffy coat of right ventricular blood were more tumorigenic than tryptically dispersed cells from solid tumors. With the new method circulating tumor cells can be detected at concentrations as Low as 3 cells/μl of buffy coat, or approximately 60 cells/ml of whole blood. The morphologic and ultrastructural features of the primary tumor were generally retained in both the circulating and tryptically dispersed cells, us shown by light and electron microscopy. A sparse distribution of intermediate filaments was revealed by high-voltage electron microscopy, although the filaments were not evident in conventional transmission electron micrographs. They were identified as keratin by immunofluorescence studies. 相似文献
996.
作为医生,你必须时时警惕自己在工作中可能遇到的风险,不是警察或者救火队员可能遇到的那类物理风险,而是经济风险--诸如医药费无法收回之类的,在更糟糕的情况下,你可能要用自己的名誉或职业生涯作为代价的--假如你被控医疗失当的话.如果你是初级保健诊所的医生,那更应该小心,因为你会遇见各种各样的病人,他们将带来各种各样的危险. 相似文献
997.
Kerstin M. Reinschmidt Nicolette I. Teufel-Shone Gail Bradford Rebecca L. Drummond Emma Torres Floribella Redondo Jo Jean Elenes Alicia Sanders Sylvia Gastelum Martha Moore-Monroy Salvador Barajas Lourdes Fernandez Rosy Alvidrez Jill Guernsey de Zapien Lisa K. Staten 《The journal of primary prevention》2010,31(1-2):69-83
Diabetes health disparities among Hispanic populations have been countered with federally funded health promotion and disease prevention programs. Dissemination has focused on program adaptation to local cultural contexts for greater acceptability and sustainability. Taking a broader approach and drawing on our experience in Mexican American communities at the U.S.–Mexico Border, we demonstrate how interventions are adapted at the intersection of multiple cultural contexts: the populations targeted, the community- and university-based entities designing and implementing interventions, and the field team delivering the materials. Program adaptation involves negotiations between representatives of all contexts and is imperative in promoting local ownership and program sustainability. 相似文献
998.
Purpose: Magnetoencephalography (MEG)/magnetic source imaging (MSI) is a noninvasive functional neuroimaging procedure used to localize language-specific regions in the brain. The Wada test, or intracarotid amobarbital procedure (IAP), is the gold standard in determining speech/language lateralization for presurgical planning, although it is invasive and associated with morbidity. The purpose of this study is to provide further validation on the use of MSI for presurgical language lateralization by comparing results against the IAP.
Methods: The sample consisted of 35 patients with epilepsy and/or brain tumor undergoing presurgical evaluation at the Minnesota Epilepsy Group. All patients received both an IAP and MSI to determine hemispheric language dominance. For MSI, a 148-channel MEG system was used to record activation of language-specific cortex by an auditory word-recognition task.
Results: The MSI and IAP were concordant in determining language in the hemisphere to be treated in 86% of the cases with sensitivity and specificity values of 80% and 100%, respectively.
Conclusions: The results from this study are consistent with prior research findings comparing functional neuroimaging procedures to the IAP in determining language lateralization in presurgical patients. The current study provides an important replication and support for Papanicolaou et al.'s findings in 2004 using a consecutive clinical sample from a different institution. An unusually high rate of atypical IAP language cases in this sample and differences between the two procedures are believed to explain the noted discrepancies. MSI is a viable noninvasive alternative to the IAP in the presurgical determination of language lateralization. 相似文献
Methods: The sample consisted of 35 patients with epilepsy and/or brain tumor undergoing presurgical evaluation at the Minnesota Epilepsy Group. All patients received both an IAP and MSI to determine hemispheric language dominance. For MSI, a 148-channel MEG system was used to record activation of language-specific cortex by an auditory word-recognition task.
Results: The MSI and IAP were concordant in determining language in the hemisphere to be treated in 86% of the cases with sensitivity and specificity values of 80% and 100%, respectively.
Conclusions: The results from this study are consistent with prior research findings comparing functional neuroimaging procedures to the IAP in determining language lateralization in presurgical patients. The current study provides an important replication and support for Papanicolaou et al.'s findings in 2004 using a consecutive clinical sample from a different institution. An unusually high rate of atypical IAP language cases in this sample and differences between the two procedures are believed to explain the noted discrepancies. MSI is a viable noninvasive alternative to the IAP in the presurgical determination of language lateralization. 相似文献
999.
Family data are useful for estimating disease risk in carriers of specific genotypes of a given gene (penetrance). Penetrance is frequently estimated assuming that relatives' phenotypes are independent, given their genotypes for the gene of interest. This assumption is unrealistic when multiple shared risk factors contribute to disease risk. In this setting, the phenotypes of relatives are correlated even after adjustment for the genotypes of any one gene (residual correlation). Many methods have been proposed to address this problem, but their performance has not been evaluated systematically. In simulations we generated genotypes for a rare (frequency 0.35%) allele of moderate penetrance, and a common (frequency 15%) allele of low penetrance, and then generated correlated disease survival times using the Clayton‐Oakes copula model. We ascertained families using both population and clinic designs. We then compared the estimates of several methods to the optimal ones obtained from the model used to generate the data. We found that penetrance estimates for common low‐risk genotypes were more robust to model misspecification than those for rare, moderate‐risk genotypes. For the latter, penetrance estimates obtained ignoring residual disease correlation had large biases. Also biased were estimates based only on families that segregate the risk allele. In contrast, a method for accommodating phenotype correlation by assuming the presence of genetic heterogeneity performed nearly optimally, even when the survival data were coded as binary outcomes. We conclude that penetrance estimates that accommodate residual phenotype correlation (even only approximately) outperform those that ignore it, and that coding censored survival outcomes as binary does not substantially increase the mean‐square errror of the estimates, provided the censoring is not extensive. Genet. Epidemiol. 34: 373–381, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
1000.
An emerging role for nurses is that of expert witness for medical liability cases that involve nursing care. Medical liability cases require that the trier of evidence (judge or jury) have an understanding of the facts and the relevant standards of the case for equitable resolution. The attorney, judge, or jury member may not possess the information necessary to understand the issues. Someone with the requisite knowledge and skills to review the information, interpret facts, offer an opinion about whether or not the standard of care was met, and explain this to the appropriate people is crucial for the legal system to work. If nursing care is at issue, that expert is a nurse with the appropriate knowledge, experience, and education. This report explores the role, qualifications, and expectations for nurses who serve as expert witnesses. Personal insights from the authors will provide practical information for nurses who are interested in the role. Copyright © 2001 by W.B. Saunders Company 相似文献