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981.
BACKGROUND: To ascertain disease and functional capacity in community-resident disabled older women in the Women's Health and Aging Study (WHAS), a prospective investigation of the causes and course of disability, a home-based standardized physical examination and performance test battery were developed. Thirty-nine tests were administered, 9 by a lay interviewer and 30 by a nurse. This scope and intensity of testing had not been performed previously in a home environment or on such a functionally limited population. Thus, substantial developmental work was required. This report describes the administrative procedures and field experience for each exam component, highlighting innovations pertinent to home administration. METHODS: Exclusion criteria, safety issues, administration time, completion rates, and reasons for incomplete data are reported. Administration time is based on 30 exams conducted over a 3-week period 90% of the way through baseline data collection. Completion status was determined using all 1,002 participants and is categorized as follows: complete; partial; not done, health; not done, other; and refused. RESULTS: Seventy-two percent of the screened, eligible respondents completed the 30-min interviewer-administered physical assessment and the 2-hr, 10-min nurse examination. Classifiable data were obtained for 90% of participants on 36 examination items. Lower completion rates were obtained on the other three tests primarily due to exclusions for health-related conditions; environmental constraints and participant refusal were minimal. CONCLUSION: Extensive, research-oriented physical evaluation can be successfully and safely performed in a home setting. In future studies, home-based examination may be preferable, as participation in the WHAS examination substantially exceeded rates for clinic-based exams in similar populations.  相似文献   
982.
Recent studies have shown that the brain is not a barrier to successful active immunotherapy that uses gene-modified autologous tumor cell vaccines. In this study, we compared the efficacy of two types of vaccines for the treatment of tumors within the central nervous system (CNS): dendritic cell (DC)-based vaccines pulsed with either tumor extract or tumor RNA, and cytokine gene-modified tumor vaccines. Using the B16/F10 murine melanoma (B16) as a model for CNS tumor, we show that vaccination with bone marrow-generated DCs, pulsed with either B16 cell extract or B16 total RNA, can induce specific cytotoxic T lymphocytes against B16 tumor cells. Both types of DC vaccines were able to protect animals from tumors located in the CNS. DC-based vaccines also led to prolonged survival in mice with tumors placed before the initiation of vaccine therapy. The DC-based vaccines were at least as effective, if not more so, as vaccines containing B16 tumor cells in which the granulocytic macrophage colony-stimulating factor gene had been modified. These data support the use of DC-based vaccines for the treatment of patients with CNS tumors.  相似文献   
983.
Digoxin, a cardiac glycoside, is a substrate of the multidrug transporter P-glycoprotein (Pgp), and in rats has also been identified as a substrate for cytochrome P450 3A (CYP3A). Ketoconazole, an antifungal agent, was shown to inhibit Pgp in a multidrug-resistant cell line, and is known to be a potent inhibitor of CYP3A. Here, we determined the effects of ketoconazole on digoxin absorption and disposition in rats. Digoxin was administered intravenously or orally with or without a concomitant oral dose of ketoconazole. When given intravenously, digoxin AUC increased from 93 +/- 22 to 486 +/- 26 microg x h/l with ketoconazole administration. Similarly, ketoconazole raised the AUC of orally administered digoxin from 63 +/- 17 to 411 +/- 50 microg x h/l. Concomitant ketoconazole administration prolonged digoxin elimination, yielding a nonlinear pharmacokinetic profile. Using time-averaged values, digoxin bioavailability increased from 0.68 +/- 0.18 to 0.84 +/- 0.10, while mean absorption time was reduced from 1.1 +/- 0.4 to 0.3 +/- 0.1 h. Thus, in rats, ketoconazole increases digoxin plasma concentrations, rate of absorption and bioavailability. Although the effects of ketoconazole on AUC could be explained by inhibition of both CYP3A and Pgp, which cannot be differentiated in this study, the decreased mean absorption time can only be explained by inhibition of Pgp in the intestine.  相似文献   
984.
985.
The surface EMG area often exhibits progressive enlargement during a submaximal fatiguing contraction, but the underlying reasons still remain uncertain. Fatigue-induced changes in the surface-detected motor unit action potentials (S-MUAPs) of 10 human thenar motor units (MUs) with widely differing physiological properties were examined. After 2 min of repetitive 40-Hz stimulation, the size of the S-MUAPs of all MUs increased, the magnitude of which was negatively correlated with their tetanic tension changes. These findings suggest that during muscle fatigue, in addition to reflecting recruitment of new MUs and increases in firing rates of the active MUs, the surface EMG may also be markedly influenced by changes in the S-MUAPs, especially in fast fatigable muscles.  相似文献   
986.
Nimbus Inc. (Rancho Cordova, CA) and the University of Pittsburgh have completed the second year of development of a totally implanted axial flow blood pump under the National Institutes of Health Innovative Ventricular Assist System Program. The focus this year has been on completing pump hydraulic development and addressing the development of the other key system components. Having demonstrated satisfactory pump hydraulic and biocompatibility performance, pump development has focused on design features that improve pump manufacturability. A controller featuring full redundancy has been designed and is in the breadboard test phase. Initial printed circuit layout of this circuit has shown it to be appropriately sized at 5 x 6 cm to be compatible with implantation. A completely implantable system requires the use of a transcutaneous energy transformer system (TETS) and a diagnostic telemetry system. The TETS power circuitry has been redesigned incorporating an improved, more reliable operating topography. A telemetry circuit is undergoing characterization testing. Closed loop speed control algorithms are being tested in vitro and in vivo with good success. Eleven in vivo tests were conducted with durations from 1 to 195 days. Endurance pumps have passed the 6 month interval with minimal bearing wear. All aspects of the program continue to function under formal quality assurance.  相似文献   
987.
STUDY OBJECTIVE: To determine the efficacy of IV immunoglobulin (IVIg) in severe asthma to reduce steroid requirements. DESIGN: Pre- and posttreatment measurements were analyzed using Dunnett's multiple comparison procedure. SETTING: Hospital clinical research center. PATIENTS: Eleven adolescents and adults with severe, steroid-dependent asthma enrolled over a 14-month period. INTERVENTIONS: IVIg was administered at a dose of 2 g/kg every 4 weeks for a total of seven infusions. MEASUREMENTS AND RESULTS: Steroid requirements, pulmonary function including lung volumes, symptom scores, bone densitometry, and airway reactivity monitored by methacholine challenge were followed over the course of 7 months. A significant decrease in steroid usage was achieved. Despite substantial steroid reduction, the patients demonstrated improvement in their pulmonary function and symptom scores. The responses to methacholine challenge were unaffected by IVIg treatment. CONCLUSIONS: IVIg provides a potentially important adjunctive therapy in severe asthma, reducing oral steroid requirements and steroid side effects without deterioration of lung function.  相似文献   
988.
989.
Coronary artery surgery with cardioplegia in high risk patients carries a risk of myocardial ischaemia and, without cardiopulmonary bypass, is not always technically feasible. The authors assessed an alternative, surgery on the beating heart with haemodynamic assist by cardiopulmonary bypass in 43 consecutive patients with poor left ventricular function (mean ejection fraction: 0.26), evolving myocardial ischaemia or acute myocardial infarction, old age (mean: 79.5 years) and comorbid conditions. Results were assessed mainly on clinical criteria. In addition, 9 patients had pre- and post-cardiopulmonary bypass measurements of markers of myocardial ischaemia (troponine Ic) and systemic inflammation (interleukines 6 and 10, elastase). In 6 cases, right atrial biopsy was analysed for expression of messenger ribonucleic acid coding for heat shock protein (HSP) 70; the data were compared with those of patients operated under warm blood cardioplegia. There was one cardiac death and one myocardial infarction. Myocardial conservation was confirmed by the minimal increase in troponine Ic levels and the significant increase in HSP 70 in RNA suggesting myocardial adaptation to stress. On the other hand, the minimal concentrations of mediators of inflammation were not significantly changed. In selected high risk patients, coronary revascularisation on the beating heart under cardiopulmonary bypass could be a valuable alternative. It conserves the potentially deleterious effects of cardiopulmonary bypass but peroperative global myocardial ischaemia, an important factor in the aggressivity of cardiac surgery, is eliminated.  相似文献   
990.
We report the findings from liver biopsies of three patients with polyglandular autoimmune disease type 1. The livers in two patients had histologic features of chronic hepatitis that eventuated in bridging fibrosis and cirrhosis over a period of several years. Nonspecific lobular and portal tract inflammation was present in the liver biopsy of the third patient. Although these patients did not have liver-specific autoantibodies, the liver disease in polyglandular autoimmune disease type 1 possibly represents an expression of autoimmune hepatitis.  相似文献   
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