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排序方式: 共有1247条查询结果,搜索用时 78 毫秒
971.
Lynda H Powell Peter Meyer Gerson Weiss Karen A Matthews Nanette Santoro John F Randolph Miriam Schocken Joan Skurnick Marcia G Ory Kim Sutton-Tyrrell 《Women's health issues》2005,15(4):179-186
BACKGROUND: Hysterectomy for a benign condition is common, particularly in the underserved. The objective was to determine if ethnic differences could be explained by known risk factors. METHODS: A phone survey was conducted at random on 15,160 women, ages 40-55, from seven US cities. Subjects were 49.9% Caucasian, 28.1% African American, 12.3% Hispanic, and 9.8% Asian American. RESULTS: Ethnicity was associated with past hysterectomy (odds ratio [OR]: Caucasian = 1.0, African American = 1.66; confidence interval [CI] = 1.46-1.88, Hispanic = 1.64, CI = 1.29-2.07; Asian American = 0.44, CI = 0.34-0.56), after adjustment for age, education, fibroids, body mass index, marital status, smoking, geographic site, and country of education. CONCLUSION: Because the highest rates occurred in the disadvantaged African American and Hispanic subgroups, and could not be explained by known risk factors, disparity in the form of overuse in these disadvantaged groups may exist. 相似文献
972.
Pap test in a high-risk population comparison of conventional and liquid-base cytology 总被引:3,自引:0,他引:3
Utagawa ML Pereira SM Makabe S Maeda MY Marques JA Santoro CL Di Loreto C Aguiar LS Pitolli JE Das Dores GB Castelo A Longatto Filho A 《Diagnostic cytopathology》2004,31(3):169-172
Liquid‐based cytology (LBC) is believed to have better sensitivity than conventional smears (CSs) and offers the possibility to perform molecular assay. The goal of this work was to study the performance of CS and LBC in a high‐risk population and to compare the results with the hybrid capture (HC) II for high‐risk human papillomavirus (HPV). Samples were collected from selected women with clinical suspicions of low genital tract lesion at Pérola Biygnton Hospital (São Paulo, Brazil). After CS preparation, the brush was introduced in the endocervix and a new sample was collected and rinsed in the preservative medium of the system. The residual material was used to HC2. From 925 cases, LBC was unsatisfactory in 4 (1.51%) cases and CS was unsatisfactory in 100 cases (10.81%); among theses cases HC2+ reactions was observed in 54 (54%) CSs and 3 (21.4%) LBCs. Considering cases with atypia of undetermined significance (squamous and glandular), 85 (77.27%) cases from LBC and 44 (86.4%) from CS were positive for HC2 assay for high‐risk DNA‐HPV. The difference among the methods was not significant (P < 0.38). The diagnosis improvement of LBC in comparison with CS was 86% in satisfactory samples, 92.76% in undetermined atypical lesions (including glandular), 83% in positive low‐grade squamous intraepithelial lesions (LSIL+), and 86.84% in high‐grade SIL+ (HSIL+). HC2+ reactions were observed in 144 CS cases and 266 LBC cases with abnormalities. Our results have showed that LBC was superior to CS in a high‐risk population to detect lesions with high concordance with HC2+ reactions; CSs also exhibit a high concordance with HC2 assay but with inferior performance to detect lesions. Diagn. Cytopathol. 2004;31:169–172. © 2004 Wiley‐Liss, Inc. 相似文献
973.
Gerson LW Hoover R McCoy S Palmisano B 《JEMS : a journal of emergency medical services》1991,16(6):45-48
Sometimes, the only contact elderly patients have with outside medical services is through the EMS network. Find out how one city uses prehospital providers to link these patients with community services tailored to their needs. 相似文献
974.
Lukic B Zapanta CM Khalapyan T Connell J Pae WE Myers JL Wilson RP Undar A Rosenberg G Weiss WJ 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2007,53(3):379-384
Penn State is currently developing a 12-mL, pulsatile, pneumatically driven pediatric ventricular assist device intended to be used in infants. After extensive in vitro testing of the pump in a passive-filling, mock circulatory loop, an acute animal study was performed to obtain data with a contracting ventricle. The objectives were to determine the range of pneumatic pressures and time required to completely fill and empty the pediatric ventricular assist device under various physiologic conditions, simulate reductions in ventricular contractility and blood volume, and provide data for validation of the mock circulatory loop. A 15-kg goat was used. The cannulation was achieved via left thoracotomy from the left ventricle to the descending aorta. The pump rate and systolic duration were controlled manually to maintain complete filling and ejection. The mean ejection time ranged from 280 ms to 382 ms when the systolic pressure ranged from 350 mm Hg to 200 mm Hg. The mean filling time ranged from 352 ms to 490 ms, for the diastolic pressure range of -60 mm Hg to 0 mm Hg. Esmolol produced a decrease in left ventricular pressure, required longer pump filling time, and reduced LVAD flow. 相似文献
975.
Serum leptin concentration, adiposity, and body fat distribution in Mexican-Americans 总被引:1,自引:0,他引:1
Peltz G Sanderson M Pérez A Sexton K Ochoa Casares D Fadden MK 《Archives of medical research》2007,38(5):563-570
BACKGROUND: Leptin is strongly associated with adiposity and few studies have investigated its role in Mexican-Americans. The aims of this study were to examine the association of serum leptin concentration with adiposity and body fat distribution in Mexican-Americans and to develop a predictive model of serum leptin concentration for this ethnic group. METHODS: Three hundred fifty-two college students (242 women, 110 men; age 18-30 years) were evaluated in this cross-sectional study. Body fat content was assessed using bioelectrical impedance analysis. Correlation between serum leptin levels and several markers of adiposity and body fat distribution were examined in both men and women. Multiple regression analysis was performed to create the predictive model. RESULTS: Women had higher serum leptin concentrations than men for the same levels of adiposity. After controlling for gender and body fat, only fat mass (FM) expressed in kg, was significantly correlated with serum leptin concentration in men (partial rho = 0.811, p <0.001), whereas body mass index (BMI), hip circumference (HC), and FM expressed in kg, were significantly correlated with serum leptin concentration in women (partial rho = 0.214, p <0.001; partial rho = 0.201, p <0.01; and partial rho = 0.818, p <0.001, respectively). Percent body fat (PBF) was the only significant predictor of serum leptin concentration among men, explaining 42% of the variance in serum leptin concentration. In addition to PBF, waist circumference (WC) and HC were significant predictors of serum leptin concentration among women explaining 65% of the variance in serum leptin concentration. CONCLUSIONS: Serum leptin concentration is a function of adiposity as determined by PBF in both Mexican-American men and women. HC and WC are associated with serum leptin concentration in Mexican-American women but not in men. BMI alone should not be used in evaluating the association of serum leptin concentration with body fatness in Mexican-Americans. 相似文献
976.
Lauren B Gerson George Triadafilopoulos Peyman Sahbaie Winston Young Sheldon Sloan Malcolm Robinson Philip B MinerJr Jerry D Gardner 《BMC gastroenterology》2008,8(1):15
Background
A Stanford University study reported that in asymptomatic GERD patients who were being treated with a proton pump inhibitor (PPI), 50% had pathologic esophageal acid exposure. 相似文献977.
978.
Tse W Libow LS Neufeld R Lesser G Frank J Dolan S Tarshish C Gracies JM Olanow CW Koller WC Hälbig TD 《Archives of gerontology and geriatrics》2008,46(3):359-366
We studied the prevalence of movement disorders in a large nursing home population (397 patients, mean age 86 years) in New York City. Patients were first evaluated by specially trained research coordinators and final clinical diagnoses were confirmed by a movement disorder specialist. A movement disorder was identified in 21% of patients (83/397). The most frequent movement disorders were essential tremor (ET) (8.8%) and parkinsonism (7.1%). Only half of those admitted with a diagnosis of parkinsonism were confirmed in their diagnosis by the movement disorder specialists. Three percent of patients exhibited drug-induced tremor, 1.3% had dystonia, 0.5% had myoclonus and 0.3% had generalized dyskinesias. Overall, our findings underline the high frequency of movement disorders in a nursing home population. The discrepancy between our findings and the prevalence rates for parkinsonism reported on the initial transfer diagnosis emphasizes the difficulty of accurate diagnosis of movement disorders and in particular parkinsonism. 相似文献
979.
An unusual case of autoimmune hemolytic anemia with reticulocytopenia, erythroid dysplasia, and an IgG2 autoanti-U 总被引:1,自引:0,他引:1
GR Roush ; NS Rosenthal ; SL Gerson ; EM Toy ; P McCarthy ; NV Hirschler ; R Yomtovian 《Transfusion》1996,36(6):575-580
BACKGROUND: Autoantibodies with anti-U specificity, usually in combination with autoantibodies of other specificities, have occasionally been identified in association with autoimmune hemolytic anemia. A case of life-threatening autoimmune hemolytic anemia, characterized by several atypical features, including apparent intravascular hemolysis associated with an IgG2 anti-U, reticulocytopenia, and bone marrow dyserythropoiesis is described. CASE REPORT: A 36-year-old man with a severe case of acute-onset autoimmune hemolytic anemia was admitted to another hospital; he had a hematocrit of 15 percent, elevated bilirubin and lactate dehydrogenase, and positive direct and indirect antiglobulin tests. He received 7 units of incompatible red cells without improvement in hematocrit, and he was transferred to University Hospitals of Cleveland (OH). He was jaundiced and became syncopal in the sitting position. His serum was reddish pink; he had a hematocrit of 11.8 percent and a reticulocyte count of 2.5 percent. No spherocytes were observed in the peripheral blood smear. Shortly after admission, the hematocrit fell to 6.9 percent. He was given 3 units of “least-incompatible” red cells and was started on prednisone, with little improvement. An IgG2 autoanti-U was detected in his serum. Seven units of U- red cells were transfused over the next 4 days. The hematocrit improved to 23 percent and continued to rise without further transfusion. A bone marrow examination, initially revealing erythroid hyperplasia accompanied by dyserythropoiesis, became morphologically normal. Drug studies failed to show evidence of drug-related hemolysis. He remains well 2 years after discharge without evidence of recurrent hemolysis. CONCLUSION: Severe life-threatening autoimmune hemolytic anemia, in this instance induced by an autoanti-U, may be associated with IgG2 autoantibody and characterized by apparent intravascular hemolysis and bone marrow dyserythropoiesis. Early treatment with U- blood, in addition to steroids, may be beneficial. 相似文献
980.
Human mesenchymal stem cells (hMSC)-nonhematopoietic cells within the bone marrow microenvironment that can be culture expanded to a uniform population of fibroblastic cells-have been shown to support long-term hematopoiesis of CD34+ cells. Because direct contact between stromal elements and CD34+ cells enhances long-term engraftment, we postulated that hMSC would be a good alternative to the more heterogeneous stroma currently used in gene transfer studies. We used hMSC to support retroviral gene transfer of the G156A MGMT (deltaMGMT) gene encoding an alkyltransferase (AGT), which confers drug resistance to a combination of O6-benzylguanine (BG) plus the alkylating agents BCNU and temozolomide (TMZ) in human hematopoietic progenitors. In the presence of IL-3, IL-6, SCF, or leukemia inhibitory factor (LIF) and Flt-3 ligand, hMSC facilitated expansion and retroviral transduction of human peripheral blood-mobilized CD34+ cells. Furthermore, the transduced cells expressed AGT in 29% of hematopoietic cells and were 5-fold more resistant to BCNU and TMZ than were untransduced cells. Unirradiated hMSC present as support cells were simultaneously transduced and expressed AGT in 26% of the cells. Thus, the homogeneous nature of hMSC, and their ability to support gene transfer and be transduced themselves suggest they may be useful in clinical gene transfer protocols and have broad therapeutic applications. 相似文献