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排序方式: 共有1843条查询结果,搜索用时 31 毫秒
81.
BACKGROUND: A large portion of the elderly population of the United States fails to receive an annual influenza vaccination. Minorities may receive disproportionately fewer vaccinations. The objectives of this study were to (a) estimate the levels of influenza vaccination among noninstitutionalized, U.S. citizens, 65 years and older, (b) examine the immunization levels among minority racial and ethnic groups relative to various majority groupings, and (c) explore potential factors that may contribute to disparities in vaccination levels. METHODS: We analyzed data from the 1996 Medical Expenditure Panel Survey to compare influenza vaccination levels of different racial and ethnic groups among 2,309 persons aged 65 years and older. RESULTS: Whites had 68.0% (+/- SE 1.5%) current influenza vaccination, Hispanics 61.7% (+/- SE 4.1%), and blacks 47.3% (+/- SE 4.3%). Blacks differed significantly compared to whites. Adjustment for potential confounders such as increased health risk, age distribution, perceived health status, family size, poverty level, and the number of ambulatory visits to a health care provider failed to change this difference substantially. CONCLUSIONS: In 1996, among elderly noninstitutionalized, U.S. citizens, blacks relative to whites were less likely to have current influenza vaccinations. This relationship remained significant even after adjustments for potential confounding variables. 相似文献
82.
CNN-Gd(3+) enables cell nucleus molecular imaging of prostate cancer cells: the last 600 nm 总被引:2,自引:0,他引:2
Heckl S Debus J Jenne J Pipkorn R Waldeck W Spring H Rastert R von der Lieth CW Braun K 《Cancer research》2002,62(23):7018-7024
Molecular imaging is defined as the characterization and measurement of biological processes at the cellular and molecular level. Molecular imaging, therefore, necessitates a sufficient amount of contrast agent within the cell. Consequently, we realized that the intracellular uptake and cell compartment specificity of the commonly used interstitial contrast agent gadolinium (Gd(3+)) with a cell-nucleus directed peptide module could be helpful. This modular molecule is characterized by a Gd(3+)-complex module that is bound to a transmembrane transport unit (TPU) of human origin and further to a nucleus-directed address module (nuclear localization sequence) resulting in a specific cell nucleus-directed nuclear localization sequence-conjugated Gd(3+)-complex (CNN-Gd(3+)-complex). By use of magnetic resonance imaging, Gd(3+) was detected within DU-145 prostate cancer cells after only 10 min. The nuclear localization was confirmed with confocal laser scanning microscopy. The resulting MRI signal enhancement only slightly decreased over the next 48 h compared with an absolute loss of signal enhancement after only 8 h when a random target sequence was used. Therefore, our method seems promising for in vivo application in molecular imaging. 相似文献
83.
MATERIAL: 28 stereotactic biopsies of organic brain processes (brain tumours) were performed in the years 1997-2000 in the Department of Neurosurgery, Medical University of Warsaw. In this series the lesions were located in corpus callosum in 5 patients, in basal nuclei in 9, and deeply in the white matter of cerebral hemispheres in 14. METHOD: The Baklund biopsy kit and Leksell's stereotactic frame were used, target localisation was based on the CT scan. Histological verification was based on hematoxillin--eosin staining, completed with histochemical evaluation if necessary. In 9 patients intraoperative smear evaluation was performed. RESULTS: Sensitivity of stereotactic biopsies was 86% (24/28), although the rate of conclusive biopsies was lower, being 60% (17/28). False negative results were observed in 14% of the patients (4/28). Analysis of the results revealed, that the sensitivity was not dependent on the size, neither on the location of the tumour, but was related to its morphology. The false negative results were obtained in the tumours with significant necrosis (as seen on CT scans). There were no surgical complications in this series. CONCLUSIONS: 1. Difficulties in stereotactic biopsies of brain tumours are associated mainly with tumour morphology. In tumours with marked necrosis, other degenerative changes or cystic ones, higher risk of non-conclusive biopsy may be expected. 2. Size of the tumour and its location do not affect the diagnosis based on the stereotactic biopsies. 3. In the polymorphic tumours, the policy to take biopsy material from different tumour sites, should be a rule, as different parts of the lesion may represent different stages of malignancy and histological evaluation of separate parts of the tumour may lead to inadequate oncological treatment. 相似文献
84.
With the objective of characterizing the underlying conditions in younger patients with cognitive symptoms, 314 consecutive patients were studied, aged <60 years, referred to a multidisciplinary memory clinic over a period of 54 months. Fifteen percent of the patients fulfilled Diagnostic and Statistical Manual IV criteria for dementia, 17% had selective cognitive deficits, and 55% had no cognitive deficits. Cognitive symptoms in younger patients rarely reflect dementia but more often other medical and psychiatric conditions. 相似文献
85.
Morris KT Vetto JT Petty JK Lum SS Schmidt WA Toth-Fejel S Pommier RF 《American journal of surgery》2002,184(4):346-347
BACKGROUND: The purpose of this study was to develop a rapid and accurate diagnostic test for palpable breast masses in women under age 40. METHODS: Masses were evaluated utilitzing a modified triple test score (MTTS), which assigned scores of 1 point for benign, 2 points for suspicious, or 3 points for malignant findings from physical examination, ultrasonography, and fine needle aspiration. The MTTS was the sum of the three scores and was correlated with biopsy or follow-up. RESULTS: Among 113 masses, 100 scored 3 points, 8 scored 4 points; all were benign. Three scored 5 points; 1 was malignant. Two scored >or=6 points: both were malignant. CONCLUSIONS: The MTTS has 100% diagnostic accuracy when other than 5 points. Masses scoring or=6 points may proceed to definitive therapy. Masses scoring 5 points (3%) require biopsy. This approach avoids open biopsy in the majority of cases, while capturing all malignancies. 相似文献
86.
Booser DJ Perez-Soler R Cossum P Esparza-Guerra L Wu QP Zou Y Priebe W Hortobagyi GN 《Cancer chemotherapy and pharmacology》2000,46(5):427-432
Annamycin is a highly lipophilic anthracycline with the ability to bypass the MDR-1 mechanism of cellular drug resistance.
In this phase I study, annamycin entrapped in liposomes was administered by a 1- to 2-h intravenous infusion at 3-week intervals.
Thirty-six patients with relapsed solid tumors were treated and 109 courses were administered at doses ranging from 3 to 240 mg/m2. The dose-limiting toxicity was thrombocytopenia. Five patients had a probable allergic reaction, requiring discontinuation
of treatment in one. Treatment was well tolerated otherwise. No cardiac toxicity was seen on endomyocardial biopsy of four
patients studied. There was limited gastrointestinal toxicity and no alopecia. No objective tumor responses were observed.
Pharmacokinetic studies at 24, 120 and 240 mg/m2 showed a biexponential plasma concentration-versus-time profile. There was a linear relationship between the dose and the
maximal plasma concentration with relatively constant plasma clearance values. The maximum tolerated dose (MTD) for liposomal
annamycin defined in this study is 210 mg/m2. Because of a subsequent change in the formulation of the drug, future studies will use 190 mg/m2 as the MTD.
Received: 28 December 1999 / Accepted: 29 June 2000 相似文献
87.
Hackert T Werner J Uhl W Gebhard MM Büchler MW Schmidt J 《American journal of surgery》2005,189(1):92-97
BACKGROUND: Graft pancreatitis is a major complication after pancreas transplantation. Antithrombin III (AT III) is an anticoagulatory and anti-inflammatory substance. The aim of our study was to evaluate a prophylactic application of AT III in experimental pancreas transplantation. METHODS: Pancreas transplantation was performed in rats. Cold ischemia time (University of Wisconsin solution at 4 degrees C) was 12 hours. After 4 hours of reperfusion, pancreatic enzymes were assessed and the pancreas was evaluated by intravital microscopy and histologic and immunohistochemical examination. Recipients were allocated randomly to 2 groups: 1 control group (n = 6) and 1 group in which recipients received 125 IU AT III/kg 30 minutes before reperfusion (n = 6). Six animals that did not undergo transplantation served as healthy controls. RESULTS: Enzyme levels showed no differences between the 2 transplantation groups but were significantly (P <.05) higher than in the control group. Histologic damage was significantly less evident in animals that received AT III compared with transplantation animals that did not receive AT III. During intravital microscopy, animals receiving AT III showed significantly higher capillary and venular erythrocyte velocities compared with untreated transplantation animals. The leukocyte-endothelium interaction in postcapillary venules was decreased significantly in animals with AT III treatment. CONCLUSIONS: AT III pretreatment decreases tissue damage by attenuating microcirculatory disturbances and leukocyte adherence in experimental graft pancreatitis by its anti-inflammatory and anticoagulatory properties. 相似文献
88.
89.
Cocaine increases human immunodeficiency virus type 1 neuroinvasion through remodeling brain microvascular endothelial cells 总被引:2,自引:0,他引:2