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991.
On average, most healthcare facilities are doing less than they should in the areas of source reduction and recycling, and will likely do so until mandated by law. The main reasons for this are ever-tightening healthcare budgets, limited staffing, and the cost of operating recycling programs compared to the cost of general solid waste disposal. Poor record keeping also may also be hampering the final decision to recycle. This article, Part II on waste abatement practices in healthcare organizations, examines what factors facilities should consider in establishing a recycling program, and analyzes cost-effective collection and disposal practices.  相似文献   
992.
The history of the Medicare program, including changes that have been enacted over the years in an effort to control spiraling costs, is reviewed. Medigap insurance and preventive medical care for the elderly are examined, as is the impact of Medicare coverage for the terminally ill. Trends indicate that the Medicare system as presently structured is not financially viable. The question is: what will replace it?  相似文献   
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  1. Evidence that nitric oxide (NO) bioactivity is altered in chronic hypertension is conflicting, possibly as a result of heterogeneity in both the nature of the dysfunction and in the disease process itself. The brain is particularly vulnerable to the vascular complications of chronic hypertension, and the aim of this study was to assess whether differences in the cerebrovascular responsiveness to the NO synthase (NOS) inhibitors, NG-nitro-L-arginine methyl ester (L-NAME) and 7-nitroindazole (7-NI), and to the NO donor 3-morpholinosydnonimine (SIN-1) might indicate one possible source of these complications.
  2. Conscious spontaneously hypertensive (SHR) and WKY rats, were treated with L-NAME (30 mg kg−1, i.v.), 7-NI (25 mg kg−1, i.p.), SIN-1 (0.54 or 1.8 mg kg−1 h−1, continuous i.v. infusion) or saline (i.v.), 20 min before the measurement of local cerebral blood flow (LCBF) by the fully quantitative [14C]-iodoantipyrine autoradiographic technique.
  3. With the exception of mean arterial blood pressure (MABP), there were no significant differences in physiological parameters between SHR and WKY rats within any of the treatment groups, or between treatment groups. L-NAME treatment increased MABP by 27% in WKY and 18% in SHR groups, whilst 7-NI had no significant effect in either group. Following the lower dose of SIN-1 infusion, MABP was decreased to a similar extent in both groups (around −20%). There was no significant difference in MABP between groups following the higher dose of SIN-1, but this represented a decrease of −41% in SHR and −21% in WKY rats.
  4. With the exception of one brain region (nucleus accumbens), there were no significant differences in basal LCBF between WKY and SHR. L-NAME produced similar decreases in LCBF in both groups, ranging between −10 and −40%. The effect of 7-NI upon LCBF was more pronounced in the SHR (ranging from −34 to −57%) compared with the WKY (ranging from −14 to −43%), and in seven out of the thirteen brain areas examined there were significant differences in LCBF.
  5. Following the lower dose of SIN-1, in the WKY 8 out of the 13 brain areas examined showed significant increases in blood flow compared to the saline treated animals. In contrast, only 2 brain areas showed significant increases in flow in the SHR. In the rest of the brain areas examined the effects of SIN-1 upon LCBF were less marked than in the WKY.
  6. Infusion of the higher dose of SIN-1 resulted in further significant increases in LCBF in the WKY group (ranging between +30% and +74% compared to saline-treated animals), but no significant effects upon LCBF were found in the SHR. As a result, there were significant differences in LCBF between SIN-1-treated WKY and SHR in six brain areas. In most brain areas examined, cerebral blood flow in SHR following the higher dose of SIN-1 was less than that measured with the lower dose of SIN-1.
  7. Despite comparable reductions in MABP (∼20%) in both groups, calculated cerebrovascular resistance (CVR) confirmed that the vasodilator effects of the lower dose of SIN-1 were significantly more pronounced throughout the brain in the WKY (ranging between −3% and −50%; median=−38%) when compared to the SHR (ranging between −10% and −36%; median=−26%). In the animals treated with the higher dose of SIN-1, CVR changes were broadly similar in both groups (median=−45% in WKY and −42% in SHR), but with the reduction in MABP in SHR being twice that found in WKY, this is in keeping with an attenuated blood flow response to SIN-1 in the SHR.
  8. The results of this study indicate that NO-dependent vasodilator capacity is reduced in the cerebrovasculature of SHR. In addition, the equal responsiveness to a non-specific NOS inhibitor but an enhanced effectiveness of a specific neuronal NO inhibitor upon LCBF in the SHR could be consistent with an upregulation of the neuronal NO system.
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996.
The Cardiovascular Health Study (CHS) is an observational study of heart disease and stroke designed to evaluate risk factors and noninvasive measures and to describe and predict atherosclerotic events in older adults. Five thousand two hundred one individuals ages 65 or older were recruited from a stratified random sample of Medicare recipients from 4 US communities. This review of cross-sectional data from the CHS baseline examination describes the cigarette smoking habits of elderly persons and the relationships of smoking to lung function (spirometry) and atherosclerosis, as noninvasively measured by the ankle-arm index (AAI) and carotid ultrasonography. Only 10% of the men and 13% of the women were current smokers, and about half were former smokers. Forced expiratory flow (FEV1) was about 20% lower in current smokers when compared with never smokers. Current and former smoking were strongly associated with an increased risk for an abnormal AAI. Common and internal carotid artery walls were thicker and stenosis more common in current smokers and former smokers, when compared with never smokers. Analysis of long-term follow-up morbidity and mortality data from the CHS cohort should provide even stronger evidence of the effects of smoking in the elderly. Vigorous efforts should be made to persuade elderly smokers to quit.  相似文献   
997.
The Sugiura operation has been reported to have low operative mortality, rebleeding, and encephalopathy rates when carried out in a predominantly nonalcoholic Japanese population with good liver function. A literature review of reports of the Sugiura procedure outside Japan reveals a high complication and mortality rate when it is used as an emergency procedure in patients with advanced liver disease, especially in those with alcoholic cirrhosis. Uncontrolled studies report results that differ little from the Japanese series when the operation is confined to good-risk patients in the elective situation. Our experience with the Sugiura operation supports its role in these circumstances, especially in patients with portal vein thrombosis and normal liver function. The only good prospective controlled trial has been carried out in patients with schistosomiasis and suggests that the Sugiura operation is far superior to total shunt and may have a slight advantage over the Warren shunt because of its low incidence of postoperative encephalopathy. More controlled trials are required to establish its role in good-to moderate-risk patients with alcoholic cirrhosis.
Resumen Se ha informado que la operación de Sugiura se asocia con bajas tasas de mortalidad, de hemorragia recurrente y de encefalopatía cuando se la ejecuta en poblaciones no alcohólicas, predominantemente japonesas y con buena función hepática. Una revisión de la literatura sobre los resultados del procedimiento por fuera del Japón, revela elevadas tasas de mortalidad y de morbilidad cuando se la practica como operación de emergencia en pacientes con enfermedad hepática avanzada, especialmente en los cirróticos alcohólicos. Estudios no controlados informan resultados que no difieren grandemente de las series japonesas cuando el uso de la operación es confinado a pacientes de buen riesgo y en condiciones electivas. Nuestra experiencia con la operación de Sugiura da apoyo al rol que quede desempeñar en estas circunstancias, especialmente en pacientes con trombosis de la vena porta y función hepática normal. El único buen ensayo prospectivo y controlado ha sido realizado en pacientes con esquistosomiasis, el cual sugiere que la operación de Sugiura es superior al shunt total y que parece tener una ligera ventaja sobre el shunt de Warren en virtud de su may baja incidencia de encefalopatía postoperatoria. Se requieren ensayos clínicos controlados adicionales para definir y dejar establecido su papel en pacientes de riesgo bueno y moderado con cirrosis alcohólica.

Résumé L'opération de Sugiura est réputée pour avoir une mortalité opératoire, un taux de récidive hémorragique et d'encéphalopathie réduites lorsqu'il s'agit d'une population japonaise, non-alcoolique avec une bonne fonction hépatique. Une revue de la littérature sur l'opération de Sugiura en dehors du Japon montre des taux de complications et de mortalité lorsqu'elle est utilisée pour les cas opérés en urgence, chez les patients ayant une maladie hépatique avancée et surtout d'origine alcoolique. Des études non contrôlées ont rapporté des résultats qui ne diffèrent que peu des séries japonaises lorsque l'intervention est pratiquée uniquement chez les patients à bon risque et dans un climat non urgent. Notre expérience de l'opération de Sugiura soutient ces notions, surtout lorsqu'il s'agit de patients ayant une thrombose portale et une bonne fonction hépatique. Par ailleurs, dans la seule étude prospective et contrôlée accomplie jusqu'à présent chez le patient ayant une bilharziose, il a été démontré que l'opération de Suguira était très supérieure à l'anastomose portocave complète et pourrait être même supérieure à celle de Warren en raison d'une incidence extrêmement basse d'encéphalopathie postopératoire. D'autres études contrôlées sont nécessaires pour établir son rôle chez le patient cirrhotique et alcoolique, à risque opératoire modéré.
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998.
Age as a prognostic factor in the malignant melanoma population   总被引:3,自引:0,他引:3  
Background: The incidence of malignant melanoma is increasing faster than any other cancer, and the state of Florida has one of the highest incidence of melanoma in the United States. This increased incidence is thought to be due to the intense sunlight exposure and ultraviolet radiation exposure in the elderly population. With the increased emphasis on issues of aging, it is appropriate to study the role of age as a prognostic factor for malignant melanoma in the Florida population. Methods: A retrospective, computer-aided search identified 442 consecutively registered patients with malignant melanoma at the Cutaneous Oncology Program. All patients had stage 1 or 2 disease (cutaneous disease only) at diagnosis. Prognostic variables analyzed included the most powerful factors for stage 1 and 2 melanoma, tumor thickness, ulceration, and Clark level of invasion. Other prognostic variables included in the analysis were the clinical variables of sex and primary site (axial vs. extremity). The population was divided into patients 65 and >65 years of age. Results: Significant disease-free survival differences were encountered in the older population, with only 55% of the elderly population being disease free at 5 years compared with 65% for the younger population (p=0.0073). However, a greater percentage of patients with melanoma who were >65 years of age had ulcerated lesions (17.5% vs. 12.9%) and a greater percentage of thick lesions at diagnosis (67.2% vs. 62.7%). Both of these prognostic factors would bias the older population with a poorer survival. A stepwise regression analysis of the entire population was performed, treating age as a continuous variable. Surprisingly, increasing age along with tumor thickness were the only significant predictors for disease-free survival. After inclusion of these two prognostic variables, none of the other prognostic factors, including Clark level, ulceration, sex, and primary site, added to the prognostic model. Conclusions: From this analysis, it is apparent that geriatric patients with melanoma have a worse prognosis than a younger control population, even after the correction for the more commonly cited prognostic factors. This information should be used in mathematical modeling to identify high-risk populations who are candidates for perhaps more aggressive primary or adjuvant therapies.Presented at the 46th Annual Cancer Symposium of The Society of Surgical Oncology, Los Angeles, California, March 18–21, 1993.  相似文献   
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PURPOSE: A retrospective analysis of 48 patients treated over a 20-year period (March 1973–April 1993) was undertaken to assess the results of our practice of early surgical intervention in suppurative complications of perianal Crohn's disease. METHODS: All patients were either seen in the office within the last six months or contacted by phone. RESULTS: The average age of our patients was 30 years at initial diagnosis. Thirty-four patients (71 percent) initially presented with intestinal disease and four (8 percent) with only perianal disease. Thirteen patients (27 percent) initially presented with simultaneous intestinal and perianal disease. The various fistulas at initial presentation included 8 intersphincteric (17 percent), 14 transphincteric (29 percent), 11 complex or multiple (23 percent), 5 rectovaginal (10 percent), and 2 unclassified, for a total of 40 patients. Eight patients (17 percent) presented with only an abscess. Eighty five percent of our patients healed after their first procedure, with an average time to heal of 2.8 months. Thirteen (27 percent) patients had recurrences after initial healing of their wounds. The mean time to recurrence after healing was 5.25 years. Fifty-four percent of our recurrences (7 patients) were treated by incision and drainage of an abscess only. Seven of 13 recurrences healed after the second procedure (54 percent), and 5 of 6 healed after a third procedure (83 percent). Only seven (14 percent) of our patients underwent a proctocolectomy during the study period, through September, 1993. Our overall probability of avoiding proctectomy and healing perineal wounds of 86 percent is consistent with published literature. CONCLUSIONS: Early aggressive surgical management of suppurative complications of perianal Crohn's disease before complex management problems ensue results in a high incidence of healing and a low risk of subsequent proctectomy.  相似文献   
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