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1.
The effect of localized hyperthermia on blood flow and cis-diamminedichloroplatinum(II) (CDDP) pharmacokinetics in 7,12-dimethylbenz[a]anthracene-induced mammary adenocarcinomas was studied. Blood flow was determined in rat tumors and normal tissue immediately and 1, 2, and 3 h after local hyperthermia treatment (43 degrees C, 1 h) as well as in unheated tumors of rats. The rate of blood flow in the tumor was increased 1.9 times at the end of treatment relative to control values and returned to the control values by 3 h after hyperthermia. Similarly, the rate of blood flow in the peripheral skin around the tumor immediately after hyperthermia was 2.2 times greater than that of unheated skin and returned to near normal values by 3 h after heating. Tumor-bearing rats received CDDP 1 h before, at the beginning of, at the end of, and 1 h after hyperthermia administration. The CDDP plasma concentration versus time profiles for rats did not vary statistically between treatment groups. Two h after CDDP administration, the mean tumor CDDP concentration of the rats which received drug at the beginning of hyperthermia was statistically greater (P less than 0.05) than tumor CDDP concentrations in rats which received drug at the end of heat treatment. The latter group was given CDDP when tumor blood flow was the greatest; however, mean tumor drug concentration was lowest of all the groups. The mean drug concentration in tumor tissues of rats which received drug 1 h after hyperthermia was comparable to rats which received drug at the beginning of hyperthermia. This suggests that drug delivery or uptake in tumors may be altered when local hyperthermia is administered concurrently or sequentially.  相似文献   
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BACKGROUND: Our aims in the present study were to estimate the influences of pain and urinary symptoms on quality of life, and to determine which of these two variables has the most predictive power with respect to quality of life in young men with chronic prostatitis-like symptoms. METHODS: Chronic prostatitis-like symptoms were measured by the National Institutes of Health-Chronic Prostatitis Symptom Index. Of the 28,841 men aged 20 years who lived in the study community, 18,495 men (a response rate 64.1%) agreed to participate in the study. A total of 1057 men who complained of symptoms indicative of chronic prostatitis were included in the study. The influences of pain and urinary symptoms on quality of life were determined using logistic regression analysis. The receiver operating characteristic (ROC) curve was used to estimate the predictive ability of each of these variables with respect to quality of life. RESULTS: Results from multivariate analysis showed that both pain and urinary symptoms were associated with an increased likelihood of impaired quality of life, although pain contributed more to a reduced quality of life than urinary symptoms. Relative to men who experienced mild pain, men who experienced moderate pain had a 3.9-fold risk of poor quality of life (odds ratio [OR], 3.87; 95% confidence interval [CI], 2.86-5.23; P < 0.001) and those who experienced severe pain had a 15.7-fold risk of reduced quality of life (OR, 15.68; 95% CI, 6.59-37.35; P < 0.001). Moderate urinary symptoms were associated with a 1.4-fold risk of bother (OR, 1.41; 95% CI, 1.01-1.99; P < 0.001) and severe urinary symptoms were associated with 2.4-fold risk (OR, 2.39; 95% CI, 1.37-4.12; P < 0.001), relative to mild urinary symptoms. Comparison of the effects of pain and urinary symptoms showed that pain severity had the most predictive power for bother, quality of life, and quality-of-life impact. The areas under the ROC curves for bother, quality of life, and quality-of-life impact were 71.3%, 69.3% and 72.5%, respectively. CONCLUSION: Urinary symptoms and pain might be associated with an increased likelihood of impaired quality of life in young men with chronic prostatitis-like symptoms. In addition, our findings suggest that pain severity is the most influential variable for determining quality of life in this population.  相似文献   
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BACKGROUND: Left ventricular assist device (LVAD) support is associated with coagulopathy, bleeding, increased blood transfusion, and increased anti-HLA antibody production. Increased anti-HLA antibody production is associated with early transplant rejection, transplant coronary artery disease (CAD), and decreased post-transplant survival rates. We asked whether bridging to transplantation with an LVAD increases the risk of transplant CAD. METHODS: We reviewed data for all adults (>18 years old) who underwent heart transplantation at our institution between 1988 and 2000. After exclusion of transplant recipients who survived <3 years, we divided the remaining cohort into 2 groups: those bridged to transplantation with LVADs (mean duration of support, 149 +/- 107 days, n = 29) and those in United Network for Organ Sharing Status 1 bridged to transplantation without LVADs (controls, n = 86). We compared groups in terms of disease cause, age, sex, donor age, panel-reactive antibody testing, crossmatching, pre- and post-transplant cholesterol concentrations, diagnosis of diabetes mellitus or treated hypertension, infections, calcium channel blocker use, transplant rejection, ischemic time, cytomegalovirus infection, pre-transplant transfusion, and incidence of transplant CAD (defined as any coronary lesion identified by coronary angiography). We considered p < 0.05 to be significant. RESULTS: The bridged and control groups were similar in all respects except mean ischemic time (217 +/- 58 minutes vs 179 +/- 67 minutes, p = 0.007), post-transplant cholesterol concentration (212 +/- 55 mg/dl vs 171 +/- 66 mg/dl, p = 0.007), and pre-transplant transfusion incidence (100% vs 22%, p < 0.001). The incidence of transplant CAD was similar in both groups during a 3-year follow-up period (28% vs 17%, p = 0.238) and during total follow-up (34% vs 35%, p = 0.969). Multivariate logistic regression analysis identified cholesterol concentration at 1 year after transplantation as a significant predictor of CAD at 3 years after heart transplantation (p = 0.0029, odds ratio = 0.984). CONCLUSIONS: Bridging to transplantation with an LVAD does not increase the risk of transplant CAD. Nevertheless, aggressive prophylactic therapy to minimize potential risk factors for transplant CAD, such as increased cholesterol concentration, is warranted in all transplant recipients.  相似文献   
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Evaluation of an on-line patient exposure meter in neuroradiology   总被引:1,自引:0,他引:1  
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Pediatric knee MR imaging: pattern of injuries in the immature skeleton   总被引:3,自引:0,他引:3  
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We have reported the case of a 19-year-old black man with sickle cell disease who had swelling over the right frontal and periorbital areas. Plain roentgenograms and CT scans were consistent with frontal sinus disease. At trephination, however, sterile liquescent blood clot was found in the frontal sinus. Awareness of the orbital apex syndrome and infarction of the orbit and sinuses in patients with sickle cell disease is necessary to prevent misdiagnosis of these conditions as suppurative sinusitis.  相似文献   
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