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991.
992.
Rhodamine 123 (R123) is a permeant, cationic, fluorescent dye that localizes preferentially within mitochondria of living carcinoma cells. MGH-U1 human bladder carcinoma cells incubated in vitro with 10 microM R123 for 30 min and then irradiated at 514.5 nm with an argon ion laser underwent selective, phototoxic injury to mitochondria. Ultrastructurally, treatment with R123 plus irradiation with 10 J/cm2 caused selective, progressive mitochondrial alterations consisting of disruption of cristae, vacuolization, swelling, increasing numbers of ring-shaped and angulated mitochondria at 4 to 8 h after irradiation, and obliteration of many mitochondria at 24 to 48 h. Confocal laser scanning microscopy after treatment with R123 plus irradiation with 10 to 30 J/cm2 demonstrated altered uptake and localization of subsequently administered R123, accompanied by striking mitochondrial fragmentation. Irradiation caused a dose-dependent depletion of extractable R123, due to a photosensitized efflux that began immediately and progressed by 4 h after irradiation with 10 to 30 J/cm2; further uptake after reincubation in the presence of R123 was also quantitatively impaired in cells previously irradiated with 30 J/cm2.  相似文献   
993.
994.
Breast cancer is the number one cause of cancer death among women in the United States Virgin Islands. Consequently, the Bureau of Health has identified breast cancer as a priority health concern. Within the medical community, increasing emphasis is being placed on the importance of hereditary, familial, environmental, and behavioral risk factors to breast cancer control. Little research has been conducted regarding these factors, however, to explore their influence on breast cancer detection and breast cancer risk management. This report highlights the outcomes of a study undertaken to explore the associations between breast cancer risk, risk assessment, risk communication, screening, and receptivity to the management of breast cancer risk among women from the United States Virgin Islands. Results of this study suggest a need within the territory to expand the systems that are responsible for monitoring and reporting breast cancer trends; forums to discuss concerns of women relative to breast health; forums to discuss communication with health-care providers; and, research efforts that address breast cancer detection and control among women in the United States Virgin Islands.  相似文献   
995.
Magnetic resonance appearance of peripheral nerve sheath tumors   总被引:6,自引:0,他引:6  
Magnetic resonance imaging (MRI) was used to evaluate 22 histologically proven peripheral nerve sheath tumors, approximately two-thirds of which arose in the lower extremity. The histologic distribution was as follows: 12 schwannomas, 7 neurofibromas, and 3 malignant peripheral nerve sheath tumors (2 of which occurred in patients with neurofibromatosis). Most lesions demonstrated an intermediate to moderately bright signal on T1-weighted images and were minimally inhomogeneous. All lesions were moderately bright on proton-density-weighted images and bright on T2-weighted images, again with variable inhomogeneity. The extent of the tumor was best assessed on proton-density- and T2-weighted images. Smooth margins were noted in 19 lesions. Of the 3 remaining lesions, 2 were malignant (but had been subjected to biopsy prior to MRI), and the other lesion was a plexiform neurofibroma. MRI accurately determined the relationship between the lesion and the adjacent neurovascular structures and muscles, thereby assisting surgical management. On MRI, 5 lesions demonstrated coexistent subtle muscle atrophy along the longitudinal axis of surrounding or distally innervated musculature. This latter finding, together with the presence of a tumor in the vicinity of a large nerve trunk, suggests a peripheral nerve sheath neoplasm.The opinions and assertions contained herein are the private views of the authors and do not reflect the views of the Uniformed Services University of the Health Sciences, the Department of the Army, or of the Department of Defense  相似文献   
996.
Three families affected by the rare genetic disorder orofaciodigital syndrome, type I (OFD-1) were screened by computed tomography (CT) to determine the presence of cysts in the kidneys and liver, an association known to occur but not previously described in the radiologic literature. Renal cystic changes in four females with oral, facial, and digital malformations were variable and not distinguishable from other inherited cystic kidney diseases. One patient had biliary ectasia and hepatic cysts. “Polycystic” kidneys occurring only in female members of a family should suggest OFD-1, an X-linked dominant disorder that is lethal in utero in males. Patients known to have the syndrome should be screened for cystic renal disease.  相似文献   
997.
Acute postdisaster psychiatric disorders: identification of persons at risk   总被引:10,自引:0,他引:10  
This study examined the prevalence of four psychiatric disorders--posttraumatic stress disorder, major depression, generalized anxiety disorder, and alcohol abuse/dependence--in survivors of a jet plane crash into a hotel. Forty-six subjects were interviewed with the Diagnostic Interview Schedule/Disaster Supplement within 4-6 weeks of the event. More than half of the subjects met criteria for a psychiatric disorder after the disaster. More than two-thirds of the cases of acute postdisaster psychiatric disorders were predicted by identifying the subjects who had predisaster psychiatric histories. Predisaster psychiatric disorder predicted postdisaster psychopathology with a sensitivity of 72% and a specificity of 90%.  相似文献   
998.
We investigated the effectiveness of two brief psychotherapies, interpersonal psychotherapy and cognitive behavior therapy, for the treatment of outpatients with major depression disorder diagnosed by Research Diagnostic Criteria. Two hundred fifty patients were randomly assigned to one of four 16-week treatment conditions: interpersonal psychotherapy, cognitive behavior therapy, imipramine hydrochloride plus clinical management (as a standard reference treatment), and placebo plus clinical management. Patients in all treatments showed significant reduction in depressive symptoms and improvement in functioning over the course of treatment. There was a consistent ordering of treatments at termination, with imipramine plus clinical management generally doing best, placebo plus clinical management worst, and the two psychotherapies in between but generally closer to imipramine plus clinical management. In analyses carried out on the total samples without regard to initial severity of illness (the primary analyses), there was no evidence of greater effectiveness of one of the psychotherapies as compared with the other and no evidence that either of the psychotherapies was significantly less effective than the standard reference treatment, imipramine plus clinical management. Comparing each of the psychotherapies with the placebo plus clinical management condition, there was limited evidence of the specific effectiveness of interpersonal psychotherapy and none for cognitive behavior therapy. Superior recovery rates were found for both interpersonal psychotherapy and imipramine plus clinical management, as compared with placebo plus clinical management. On mean scores, however, there were few significant differences in effectiveness among the four treatments in the primary analyses. Secondary analyses, in which patients were dichotomized on initial level of severity of depressive symptoms and impairment of functioning, helped to explain the relative lack of significant findings in the primary analyses. Significant differences among treatments were present only for the subgroup of patients who were more severely depressed and functionally impaired; here, there was some evidence of the effectiveness of interpersonal psychotherapy with these patients and strong evidence of the effectiveness of imipramine plus clinical management. In contrast, there were no significant differences among treatments, including placebo plus clinical management, for the less severely depressed and functionally impaired patients.  相似文献   
999.
1000.
PURPOSE: To examine the historical, legal/ organizational, informatics, clinical, economic, and policy contexts underlying economic consequences of nursing diagnoses on patient outcomes. DATA SOURCES: Published literature, online material. DATA SYNTHESIS: Nursing diagnoses influence diagnostic-specific patient outcomes and other outcome variables such as length of hospital stay, morbidity, and mortality. CONCLUSIONS: Examination of the economic ramifications of nursing diagnosis on patient outcomes can be facilitated using standardized language and databases containing nursing-sensitive measures.  相似文献   
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