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861.
Needlestick transmission of hepatitis C 总被引:9,自引:0,他引:9
Hepatitis C virus (HCV) transmission following a needlestick is an important threat to health care workers. We present the case of a 29-year-old medical intern who sustained a needlestick injury from a source patient known to be infected with both human immunodeficiency virus and HCV. The case patient subsequently developed acute HCV infection. The optimal strategy for diagnosing HCV infection after occupational exposures has not been defined. At a minimum, HCV antibody and alanine aminotransferase testing should be done within several days of exposure (to assess if the health care worker is already infected with HCV) and 6 months after percutaneous, mucosal, or nonintact skin exposure to blood or infectious body fluids from an HCV-infected patient. Currently, it is not possible to prevent HCV infection after exposure. However, recent data suggest that early treatment of acute HCV infection with interferon alpha may be highly effective in preventing chronic HCV infection. These data underscore the importance of identifying persons with acute HCV infection and promptly referring them to experienced clinicians who can provide updated counseling and treatment. 相似文献
862.
Improving quality of care for acute myocardial infarction: The Guidelines Applied in Practice (GAP) Initiative 总被引:17,自引:4,他引:13
Mehta RH Montoye CK Gallogly M Baker P Blount A Faul J Roychoudhury C Borzak S Fox S Franklin M Freundl M Kline-Rogers E LaLonde T Orza M Parrish R Satwicz M Smith MJ Sobotka P Winston S Riba AA Eagle KA;GAP Steering Committee of the American College of Cardiology 《JAMA》2002,287(10):1269-1276
Context Quality of care of patients with acute myocardial infarction (AMI) has received intense attention. However, it is unknown if a structured initiative for improving care of patients with AMI can be effectively implemented at a wide variety of hospitals. Objective To measure the effects of a quality improvement project on adherence to evidence-based therapies for patients with AMI. Design and Setting The Guidelines Applied in Practice (GAP) quality improvement project, which consisted of baseline measurement, implementation of improvement strategies, and remeasurement, in 10 acute-care hospitals in southeast Michigan. Patients A random sample of Medicare and non-Medicare patients at baseline (July 1998June 1999; n = 735) and following intervention (September 1December 15, 2000; n = 914) admitted at the 10 study centers for treatment of confirmed AMI. A random sample of Medicare patients at baseline (JanuaryDecember 1998; n = 513) and at remeasurement (MarchAugust 2001; n = 388) admitted to 11 hospitals that volunteered, but were not selected, served as a control group. Intervention The GAP project consisted of a kickoff presentation; creation of customized, guideline-oriented tools designed to facilitate adherence to key quality indicators; identification and assignment of local physician and nurse opinion leaders; grand rounds site visits; and premeasurement and postmeasurement of quality indicators. Main Outcome Measures Differences in adherence to quality indicators (use of aspirin, -blockers, and angiotensin-converting enzyme [ACE] inhibitors at discharge; time to reperfusion; smoking cessation and diet counseling; and cholesterol assessment and treatment) in ideal patients, compared between baseline and postintervention samples and among Medicare patients in GAP hospitals and the control group. Results Increases in adherence to key treatments were seen in the administration of aspirin (81% vs 87%; P = .02) and -blockers (65% vs 74%; P = .04) on admission and use of aspirin (84% vs 92%; P = .002) and smoking cessation counseling (53% vs 65%; P = .02) at discharge. For most of the other indicators, nonsignificant but favorable trends toward improvement in adherence to treatment goals were observed. Compared with the control group, Medicare patients in GAP hospitals showed a significant increase in the use of aspirin at discharge (5% vs 10%; P<.001). Use of aspirin on admission, ACE inhibitors at discharge, and documentation of smoking cessation also showed a trend for greater improvement among GAP hospitals compared with control hospitals, although none of these were statistically significant. Evidence of tool use noted during chart review was associated with a very high level of adherence to most quality indicators. Conclusions Implementation of guideline-based tools for AMI may facilitate quality improvement among a variety of institutions, patients, and caregivers. This initial project provides a foundation for future initiatives aimed at quality improvement. 相似文献
863.
[目标]:研究不同和相同读片人对息肉直径进行体外自动测量时所得结果的一致性。[方法]:用16排CT扫描两个模型(QRM和Whiting模型),两个模型都包含有直径和体积已知的模拟息肉。两位读片人用三种方式来估计息肉的直径:软件测量(手工)、手工边界识别(半自动)及自动软件分割(全自动)。[结果]:对同一读片人,当使用全自动方法时,95%一致性极限范围最小(QRM范围:0.39mm~0.48mm;Whiting范围:0.24mm~0mm)。手工估计测量的极限范围大约比全自动方法要大10倍(QRM范围:3.57mm~3.21mm,Whiting范围:3.2mm~2.02mm)。全自动方法对体积的估计范围最小(范围:24.2mm^3~24.1mm^3;而半自动测量的范围为97.9mm^3~102.9mm^3.对不同读片人,当使用全自动方法时,测得直径的一致性范围最小(QRM范围:0.12mm;Whiting范围:0.16mm),而使用手工方法的一致性范围大约是全自动方法的18倍(QRM范围2.87mm;Whiting范围:2.18mm)。[结论]:通过全自动方法来测量息肉直径和体积在技术上是可行的,可使不同和相同读片人的测量结果实现更高的一致性。 相似文献
864.
Familial Aggregation and Segregation Analysis of Snoring and Symptoms of Obstructive Sleep Apnea 总被引:1,自引:0,他引:1
Catharine J. Holberg Ph.D. Sunil Natrajan M.D. Martha G. Cline M.S. Stuart F. Quan M.D. 《Sleep & breathing》2000,4(1):23-31
To investigate possible modes of inheritance that would explain familial aggregation in obstructive sleep apnea (OSA), familial correlation and segregation analyses were performed on data derived from 584 pedigrees with 2019 cases enrolled in the Tucson Epidemiologic Study of Obstructive Airways Disease (TESOAD) who were at least 10 years of age and who had information pertaining to snoring and daytime sleepiness. Data were obtained from the 9th (May 1984 to October 1985) and 12th (February 1990 to October 1992) surveys of the TESOAD, which is a random, stratified sample of the non-Hispanic Caucasian population of Tucson, Arizona. A snoring phenotype was considered present if it occurred on at least some nights. A sleep apnea phenotype was constructed if participants snored and experienced daytime sleepiness. Familial correlations for snoring showed significant mother-child and sibling correlations but not father-child correlations. For sleep apnea, significant parent-daughter but not parent-son or sibling correlations were observed. Segregation analyses for snoring with regressive familial effects and sibling, age, and obesity covariates showed no evidence for mendelian transmission. However, additional familial effects were present that suggested phenotype aggregation from polygenic or environmental factors, or both. For the sleep apnea phenotype, similar segregation analyses indicated that mendelian dominant or codominant models were possible. However, the analyses also suggested that a nongenetic model fit the data as well. In addition, consistent with the familial correlations, specific maternal- and sibling-related effects remained even after inclusion of age, gender, and obesity covariates. These data support the concept that inheritable or shared environmental factors contribute to the development of OSA and that maternal components may be more important than paternal ones.Presented in part at the Annual Meeting of the American Thoracic Society, May 21, 1997, San Francisco, California Respiratory Sciences and Sleep Disorders Centers, Department of Medicine, University of Arizona College of Medicine, Tucson, Arizona 相似文献
865.
Tumor growth is the net result of cell proliferation and cell death. To investigate the relationship between these phenomena in ductal carcinoma in situ (DCIS), we studied proliferation index (PI) in DCIS in relation to the expression of two proteins involved in the regulation of cell death, bcl-2 and p53. Thirty-nine consecutive cases of DCIS were studied. PI was determined using immunolabeling with the monoclonal antibody MIB-1. The proportion of MIB-1-positive nuclei among 500 tumor cell nuclei was determined for each case and constituted the PI. All cases were also assessed immunohistochemically for bcl-2 and p53 protein expression. DCIS cases were graded using the criteria of Holland et al. PI ranged from 0 to 57% (mean 11.2%, median 4.6%). PI was significantly lower in well-differentiated and intermediately differentiated DCIS cases (mean 7.3% and 4.8%, respectively) than in poorly differentiated lesions (mean 24%, p = 0.01). PI was significantly lower in bcl-2-positive cases than in bcl-2-negative cases (mean PI for bcl-2-positive cases 6% and for bcl-2-negative cases 26%, p = 0.01). PI was higher in lesions expressing the p53 protein than in p53 negative cases (19% versus 8.3%), but this difference did not reach statistical significance. PI was also examined in relation to combinations of bcl-2 and p53 expression. Twenty-five of the DCIS lesions (64%) showed the bcl-2-positive/p53-negative phenotype which is similar to that seen in normal breast tissue and benign lesions and can be considered the "physiologic" combination. Among these cases the mean PI was 6.4%. In contrast, 14 cases showed "aberrant" combinations of bcl-2 and p53 expression suggesting dysregulated control of apoptosis. Among these cases the mean PI was 19.6% (p = 0.03). The highest mean PI was in cases with the bcl-2-negative/p53-positive phenotype (PI = 29.7%). DCIS lesions with the physiologic bcl-2-positive/p53-negative phenotype have low PI. In contrast, DCIS lesions with "aberrant" bcl-2/p53 phenotypes have high PI. This combination may favor tumor growth and progression in DCIS. 相似文献
866.
Photocarcinogenesis in human adult skin grafts. 总被引:2,自引:0,他引:2
Carola Berking Richelle Takemoto Robert L Binder Scott M Hartman Dirk J Ruiter Patricia M Gallagher Stuart R Lessin Meenhard Herlyn 《Carcinogenesis》2002,23(1):181-187
It has been demonstrated previously that the exposure to 7,12-dimethyl[a]benzanthracene (DMBA) and UVB radiation leads to the development of epidermal cysts, squamous cell carcinomas (SCC), melanocytic hyperplasia and melanoma in human foreskins from newborns grafted to immunodeficient mice. Improved techniques in grafting full-thickness skin from adults have enabled us to study photocarcinogenesis in human skin from different body sites and from older donors. One hundred and fifty-five normal white skin specimens from the trunk and face of 53 adult individuals were grafted onto severe combined immunodeficient (SCID) and recombinase activating gene-1 (Rag-1) knockout mice and irradiated two to three times weekly with 40 mJ/cm(2) UVB or solar-simulated UV (SSUV) over a period of up to 10 months with or without one prior topical application of DMBA. Over an observation period of 2-22 months, histopathological and immunohistochemical analyses of 134 specimens revealed actinic keratoses in 30% of the DMBA- + UV-treated grafts, in 18% of the grafts exposed to SSUV only, and in 10% of the grafts exposed to UVB only. Actinic keratoses were absent in grafts treated with DMBA only. One SCC was found in an abdominal skin graft 3 months after exposure to DMBA followed by UVB. Point mutations in codon 61 of the human Ha-ras gene were detected in the SCC, five of six analyzed actinic keratoses and in non-lesional epidermis of DMBA- and UVB-treated grafts, indicating that DMBA as well as UVB alone can induce these mutations in human skin. In contrast to the previous experience with neonatal foreskin grafts, melanocytic lesions were not found except for mild hyperplasia in few cases. The data suggest that melanocytes from young individuals are more susceptible to the transforming effects of genotoxic agents than melanocytes from adults. 相似文献
867.
Charlotta Enerb?ck Dale A Porter Pankaj Seth Dennis Sgroi Justine Gaudet Stanislawa Weremowicz Cynthia C Morton Stuart Schnitt Robert L Pitts Jason Stampl Kerry Barnhart Kornelia Polyak 《Cancer research》2002,62(1):43-47
We determined, by serial analysis of gene expression (SAGE) analysis of normal and DCIS (ductal carcinoma in situ) mammary epithelial cells, that psoriasin and several other genes implicated in psoriasis are aberrantly expressed in high-grade, comedo DCIS. Real-time PCR, mRNA in situ hybridization, and immunohistochemical analysis of breast carcinomas confirmed that psoriasin is frequently overexpressed in estrogen receptor-negative tumors. To gain insight into regulatory pathways that control psoriasin expression, we developed polyclonal and monoclonal antibodies and investigated mechanisms that may account for elevated levels of psoriasin in DCIS. Here, we report that loss of attachment to extracellular matrix, growth factor deprivation, and confluent conditions dramatically up-regulate psoriasin expression in MCF10A mammary epithelial cells. All of these conditions are characteristic of high-grade DCIS and psoriatic skin lesions; therefore, the same mechanisms may be responsible for increased expression of psoriasin in vitro and in vivo. 相似文献
868.
Event-related brain potentials (ERPs) in schizophrenia for tonal and phonetic oddball tasks. 总被引:9,自引:0,他引:9
J Kayser G E Bruder C E Tenke B K Stuart X F Amador J M Gorman 《Neuropsychopharmacology》2001,49(10):832-847
BACKGROUND: Prior studies using simple target detection ("oddball") tasks with pure tones have reported asymmetric reduction of the P3 event-related potential (ERP). This study investigated the time course and topography of ERPs recorded during both tonal and phonetic oddball tasks. METHODS: Event-related potentials of 66 patients (14 unmedicated) diagnosed with schizophrenia (n = 46) or schizoaffective disorder (n = 20) and 32 healthy adults were recorded from 30 scalp electrodes during two oddball tasks using consonant-vowel syllables or complex tones. Overlapping ERP components were identified and measured by covariance-based principal components analysis. RESULTS: Schizophrenic patients showed marked, task-independent reductions of early negative potentials (N1, N2) but not reduced P3 amplitude or abnormal P3 asymmetry. Task-related hemispheric asymmetries of the N2/P3 complex were similar in healthy adults and schizophrenic patients. Poorer task performance in patients was related to ERP amplitudes, but could not account for reductions of early negativities. CONCLUSIONS: The findings suggest that both patients and control subjects activated lateralized cortical networks required for pitch (right frontotemporal) and phoneme (left parietotemporal) discrimination. Task-independent reductions of negativities between 80 and 280 msec after stimulus onset suggest a deficit of automatic stimulus classification in schizophrenia, which may be partly compensated by later effortful processing. 相似文献
869.
870.