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991.
Contributions of self-reported health to adult age differences in perceptual speed and memory were assessed for 301 adults ages 20-90. Participants were asked 4 health status questions, given 3 perceptual speed tests, 2 working memory tests, and 2 memory tests. Self-reported health was found to predict speed better than it predicted memory. Covariance structural equation modeling was used to assess the relations among age, self-reported health, perceptual speed, working memory, and memory. The results support the hypothesis that any effects of self-reported health on age differences in memory are mediated by perceptual speed.  相似文献   
992.
INTRODUCTION: Iodine containing agents are used as radiologic contrast media and for the treatment of upper respiratory infections, heart diseases, thyreotoxicosis, erythema nodosum and wound disinfection. Vegetating iododerma is a rare but severe cutaneous side effect. CASE STUDY: We report a case of iododerma in a 84 year-old patient, presenting iododerma 14 months after introduction of amiodarone treatment. Despite cessation of this therapy, an important exacerbation of the skin lesions was observed 3 months later. Therapy with cyclosporine produced a marked regression of the skin lesions. DISCUSSION: We are aware of only one other reported case of amiodarone induced iododerma, which occurred after 2 years of therapy. Our patient was also exposed to iodine containing radiographic contrast media 1 and 18 years before onset of the actual skin disease. A sensitizing role of these injections is possible, but we feel that they did not directly induce the skin eruption as all reported cases occurred within a few days after exposure. CONCLUSION: Amiodarone can exceptionally be responsible for severe iododerma. Cyclosporine is, according to our experience, a valuable therapeutic option.  相似文献   
993.
BACKGROUND: The suicide gene and prodrug, herpes simplex thymidine kinase (HStk) and ganciclovir (GCV), are now in clinical trials for recurrent malignancies. METHODS: We evaluated in vitro and in vivo efficacy of HStk gene transfer and GCV treatment of colonic adenocarcinoma in a syngeneic murine model. RESULTS: In vitro analysis demonstrated that CT-26 adenocarcinoma cells transduced with LTKOSN.2 retroviral vector inhibited the proliferation of wild-type CT-26 (nontransduced) cells after GCV exposure. Cooperative killing with HStk gene therapy was shown in vivo, mixtures of HStk CT-26 transduced cells (CT-26 TK), and nontransduced (CT-26 NV) cells and tumors containing only 9% CT-26 TK cells demonstrated complete regression after GCV (100 mg/kg). CONCLUSIONS: This in vitro and in vivo demonstration suggests that metabolic cooperation permits destruction of tumors even when gene transfer is effective only to a relatively small portion of the tumor. These important results suggest new avenues can be developed for the treatment of this lethal malignancy.  相似文献   
994.
As previously reported, we have discovered that a novel compound, NO-1886 (diethyl 4-[(4-bromo-2-cyanophenyl)carbamoyl] benzylphosphonate) has a powerful lipoprotein lipase (LPL) stimulating activity. Oral administration of NO-1886 increased LPL activity in postheparin plasma of experimental animals, resulting in the reduction of plasma triglyceride with concomitant elevation of high density lipoprotein cholesterol. However, the mechanism of NO-1886 on LPL activity is not clearly understood. To address this problem, we examined the effect of NO-1886 on LPL activity in primary rat cell culture isolated from adipose and skeletal muscle tissue. NO-1886 increased total LPL activity 18% and 23% in adipocytes at a dose of 3 and 10 micrograms/ml, respectively, and 43% at a dose of 10 micrograms/ml in skeletal muscle cells. These results indicate that NO-1886 may act directly on LPL-producing cells such as adipose and skeletal muscle.  相似文献   
995.
In the process of health planning and of the evaluation of health care, there is growing interest in assessing the quality of medical care. Traditionally, quality indexes are divided into three groups: structure, process and outcome. The first two indexes can be measured more easily and quickly, but outcome indexes are more appropriate care indicators for both health planners and patients. The introduction of quality assessment means that physicians work in order to achieve the required standards even if it does not increase the real quality of care, that data are systematically biased in order to increase the quality score and, lastly, that physicians do not rely on case-mix statistical adjustment of results. All these problems have already been evaluated by the Health Department of New York State. Since 1989, outcome data of open-heart surgery have been monitored in all cardiac surgery centers in the state. It is still open to debate whether the decreased mortality in New York State is due to the quality assessment program, to the migration of sicker patients to nearby states, or to the refusal of heart surgeons to operate on high-risk patients. In Italy as well, new rules have been introduced into health legislation in order to assess the quality of health care. Even if methodological and legislative instruments to assess quality of care are still not completely reliable in terms of assessing the quality of care with simple and effective methods, this does not exclude the need to proceed in assessing the quality of health care.  相似文献   
996.
The effects of conditions that either increase or decrease heart rate on the pharmacological properties of adenosine receptors in cultured rat myocytes were examined. Levels of A1 adenosine receptors, following prolonged treatment with electrical stimulation (ES) or the antiarrhythmic drug amiodarone, were determined using radioligand binding with the specific A1 receptor antagonist [3H]1,3-dipropyl-8-cyclopentylxanthine (CPX). The effects of lowering temperature were also explored. Exposure to amiodarone for 4 days reduced the density of A1 receptors by 19% (from 24.7 +/- 0.4 to 20.09 +/- 0.3 fmol/dish) and inhibited the rate of contraction by 60% (from 188 +/- 16 to 76 +/- 30 beats/min), without changing the receptor affinity, protein content, creatine kinase (CK) activity or cell number. Electrical stimulation at 25 degrees C elevated the density of A1 adenosine receptors by 185% (from 4.1 +/- 0.4 to 11.69 +/- 2.1 fmol/dish). Four days of reduced temperature (from 37 degrees C to either 30 or 25 degrees C) lowered the density of A1 adenosine receptors by 69 or 86%, respectively (from 24.1 +/- 1.2 to 7.4 +/- 0.4 or 3.4 +/- 0.3 fmol/dish), with no significant change in the receptor affinity, activity of CK, or lactate dehydrogenase (LDH), protein content or cell number. The observed up- and down-regulation of A1 adenosine receptors in primary myocyte cultures in response to conditions that exogenously alter the rate of contraction, is indicative of the role of adenosine receptors in adaptation of heart cells to stress.  相似文献   
997.
BACKGROUND: Detailed information regarding the spectrum and predictors of infection after heart transplantation in children is limited because of relatively small numbers of patients at any single institution. We therefore used combined data obtained from the Pediatric Heart Transplant Study Group to gain additional information regarding infectious complications in the pediatric population. METHODS: To determine the time-related risk of infection and death related to infection in a large pediatric patient population, we analyzed data related to 332 pediatric patients (undergoing heart transplantation between January 1, 1993, and December 31, 1994) from 22 institutions in the Pediatric Heart Transplant Study Group. RESULTS: Among the 332 total patients, 276 infections were identified in 136 patients. Of those patients with development of infection, a single infection episode was reported in 54% of patients, 21% had two infections, and 25% had three or more infections. Of the 276 infections, 164 (60%) were bacterial, 51 (18%) were due to cytomegalovirus, 35 (13%) were other viral (noncytomegalovirus) infections, 19 (7%) were fungal, and 7 (2%) were protozoal. Bacterial infections were more common in infants younger than 6 months of age at time of transplantation, comprising 73% of all infections as compared with 49% in patients older than 6 months of age. The incidence of bacterial infection peaked during the first month after transplantation, with the actuarial likelihood of a bacterial infection among all patients reaching 25% at 2 months. The most common sites of bacterial infection were blood and lung (74% of bacterial infections). Cytomegalovirus accounted for 59% of viral infections, with a peak hazard occurring at 2 months after transplantation. Among all infections, cytomegalovirus was less common in infants younger than 6 months of age (8% of all infections) than in older patients (25%). By multivariate analysis, risk factors for early infection included younger recipient age (p = 0.05), mechanical ventilation at time of transplantation (p = 0.0002), positive donor cytomegalovirus serologic study result with negative recipient result (p = 0.004), and longer donor ischemic time (p = 0.04). The overall mortality rate from infection was 5%, with an actuarial freedom from death related to infection of 92% at 1 year after transplantation. The mortality rate was high in patients with fungal infections (52%), yet was low for those with cytomegalovirus infection (6%). Infections accounted for 27% of the overall mortality rate in infants younger than 6 months of age, compared with 16% for older patients. CONCLUSIONS: Although most infections in pediatric heart transplant recipients are successfully treated, infection remains an important cause of posttransplantation morbidity and death, especially in infants. Bacterial infections predominate within the first month after transplantation, whereas the peak hazard for viral infections occurs approximately 2 months after transplantation. Cytomegalovirus infections are common in the pediatric transplant population, but death related to cytomegalovirus is low.  相似文献   
998.
STUDY DESIGN: This prospective study analyzed the influence of transpedicular instrumented on the operative treatment of patients with degenerative spondylolisthesis and spinal stenosis. OBJECTIVES: To determine whether the addition of transpedicular instrumented improves the clinical outcome and fusion rate of patients undergoing posterolateral fusion after decompression for spinal stenosis with concomitant degenerative spondylolisthesis. SUMMARY OF BACKGROUND DATA: Decompression is often necessary in the treatment of symptomatic patients who have degenerative spondylolisthesis and spinal stenosis. Results of recent studies demonstrated that outcomes are significantly improved if posterolateral arthrodesis is performed at the listhesed level. A meta-analysis of the literature concluded that adjunctive spinal instrumentation for this procedure can enhance the fusion rate, although the effect on clinical outcome remains uncertain. METHODS: Seventy-six patients who had symptomatic spinal stenosis associated with degenerative lumbar spondylolisthesis were prospectively studied. All patients underwent posterior decompression with concomitant posterolateral intertransverse process arthrodesis. The patients were randomized to a segmental transpedicular instrumented or noninstrumented group. RESULTS: Sixty-seven patients were available for a 2-year follow-up. Clinical outcome was excellent or good in 76% of the patients in whom instrumentation was placed and in 85% of those in whom no instrumentation was placed (P = 0.45). Successful arthrodesis occurred in 82% of the instrumented cases versus 45% of the noninstrumented cases (P = 0.0015). Overall, successful fusion did not influence patient outcome (P = 0.435). CONCLUSIONS: In patients undergoing single-level posterolateral fusion for degenerative spondylolisthesis with spinal stenosis, the use of pedicle screws may lead to a higher fusion rate, but clinical outcome shows no improvement in pain in the back and lower limbs.  相似文献   
999.
OBJECTIVES: To describe patterns of hypertension history in patients with various types of end-stage renal disease (ESRD) and in persons with normal kidney function; and to identify risk factors for the diagnosis 'hypertensive ESRD'. DESIGN: A case-control study. SETTING: Population-based. PARTICIPANTS: Patients with ESRD due to hypertension (n = 214), diabetes (n = 239), other specified causes (n = 181), unknown causes (n = 82) and control subjects drawn from the general population (n = 361). MAIN OUTCOME MEASURES: Participants' history of hypertension. RESULTS: The prevalence of hypertension was 90% in ESRD patients and 27% in controls. Only 6% of patients with hypertensive ESRD had a history of malignant hypertension. Patients with hypertensive ESRD were more likely to have been hospitalized because of hypertension (36%) than were other ESRD patients (18%) or controls (5%). ESRD of any cause was more strongly associated with hypertension of > or = 25 years duration (odds ratio 51.0, compared with normal blood pressure) than it was with hypertension of shorter duration (15-25 years: odds ratio 31.8, 5-15 years: odds ratio 16.0, < 5 years: odds ratio 21.2). Among patients who had both hypertension and ESRD, the diagnosis of 'hypertensive ESRD' was associated independently with a long duration of hypertension, greater severity of hypertension, the absence of diabetes, black race, and limited education. CONCLUSIONS: Hypertension is common among patients with ESRD. The risk of ESRD from any cause increases progressively with the duration of hypertension, and with indicators of severe hypertension. This result supports the hypothesis that nonmalignant hypertension of long duration may cause renal insufficiency. The criteria used to diagnose hypertensive ESRD are consistent with pathophysiologic and epidemiologic evidence.  相似文献   
1000.
OBJECTIVE: To evaluate a method for detecting thiazole orange-positive (TO+, reticulated) platelets in equine blood, using flow cytometry. ANIMALS: 16 healthy, equine infectious anemia virus (EIAV)-negative horses and ponies; 9 thrombocytopenic, EIAV-positive horses and ponies; and 2 thrombocytopenic, EIAV-negative horses. PROCEDURE: Blood from healthy and thrombocytopenic horses was collected by jugular venipuncture. Appropriate sample requirement and incubation time for the assay were evaluated, using blood anticoagulated with EDTA or sodium citrate, or platelet-rich plasma in sodium citrate. The sample of blood or platelet-rich plasma was incubated with thiazole orange, and flow cytometric analysis was performed. Percentage of circulating TO+ platelets was determined from fluorescence (FL-1) logarithmic histograms. RESULTS: Healthy ponies (n = 9) had 1.28 to 2.83% (mean +/- SD, 2.03 +/- 0.50%) and horses (n = 7) had 0.9 to 3.44% (2.12 +/- 1.14%) TO+ platelets in circulation. Thrombocytopenic ponies (n = 7) had 11.14 to 48.41% (26.51 +/- 11.99%) and thrombocytopenic horses (n = 4) had 2.33 to 8.52% (6.19 +/- 2.68%) TO+ platelets in circulation. Mean platelet counts for the thrombocytopenic ponies and horses were 24,400 +/- 20,500 and 39,300 +/- 13,500 platelets/microliters, respectively (reference range, 94,000 to 232,000 platelets/ microliters). CONCLUSION: Thiazole orange-positive platelets can be detected in equine blood and percentages of TO+ platelets are increased in thrombocytopenic horses. CLINICAL RELEVANCE: Enumeration of TO+ platelets may prove to be a helpful noninvasive clinical measurement of bone marrow platelet production and aid in the assessment of platelet kinetics in thrombocytopenic horses.  相似文献   
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