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41.
In erythropoietic protoporphyria (EPP), there is excessive production of protoporphyrin, primarily in the bone marrow, resulting in increased biliary excretion of this heme precursor. Some patients will develop progressive liver disease that may ultimately require liver transplantation. However, excessive production of protoporphyrin by the bone marrow continues after transplantation, which may cause recurrent disease in the allograft. This study was performed to define post-transplant survival, the risk of recurrent disease, and specific management issues in patients transplanted for EPP liver disease. The patients studied consisted of twelve males and eight females, with an average age of 31 (range, 13-56) years at the time of transplantation. The estimated maximum MELD score prior to transplant was 21 (range, 15-29). Unique complications in the perioperative period were light induced tissue damage in four patients and neuropathy in six, requiring prolonged mechanical ventilation in four. Patient and graft survival rates were 85% at 1 year, 69% at 5 years, and 47% at 10 years. Recurrent EPP liver disease occurred in 11 of 17 patients (65%) who survived more than 2 months. Three patients were retransplanted at 1.8, 12.6, and 14.5 years after the initial transplant for recurrent EPP liver disease. In conclusion, the 5-year patient survival rate in patients transplanted for EPP liver disease is good, but the recurrence of EPP liver disease appears to diminish long term graft and patient survival.  相似文献   
42.
In October 1985, the Food and Drug Administration approved a new indication of aspirin for the secondary prevention of recurrent myocardial infarction (MI) and death in patients with MI or unstable angina. Clinical trials have demonstrated the efficacy of this drug, especially when treatment is begun soon after the initial event. The antiplatelet actions of aspirin seem to be the most plausible explanation for its efficacy in reducing mortality and the rate of reinfarction. A single daily 325-mg tablet is effective and produces side-effect incidences of only zero to two percent above those produced by placebo. This article assesses the current state of knowledge regarding the value of aspirin therapy in survivors of acute MI and the implications for clinical practice.  相似文献   
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On July 25, 1989, President Bush signed a bill declaring the 1990's to be the Decade of the Brain. This offers the clinical and basic neuroscience communities an opportunity to join with the National Institute of Neurological Disorders and Stroke in moving ahead vigorously with research aimed at preventing and treating neurological disease. Neurosurgery must be an active participant in this national endeavor; its influence, skills, and contributions are needed.  相似文献   
46.
The federal Medicare Diagnosis Related Group payment mechanism is undergoing constant change. Significant interest has been generated at the health policy level regarding reimbursement for patients with complications and comorbidities. The purpose of this study was to analyze hospital resource consumption for patients in the seventeen urology non-complicating condition (CC) stratified Diagnostic Related Groups (DRGs), currently 45 percent of urology DRGs. We analyzed 185 Medicare patients in these non-CC stratified urology DRGs and found that patients with more CCs per patient had higher total hospital costs per patient, financial risk under DRGs, a greater percentage of outliers, and a higher mortality, than patients in these same DRGs with fewer CCs per patient. These findings suggest that the current DRG system is inequitable to some patients and certain hospitals vis-a-vis non-CC stratified urology DRGs. The Health Care Financing Administration has not significantly changed the complicating condition urology DRG classification, as of its recent May, 1988 legislation. Financial disincentives to treat these patients may affect both their access and quality of care in the future.  相似文献   
47.
Inhalation of benzene produces a prolongation of mouse red blood cell glycerol hemolysis time. This was not observed in red blood cells directly incubated in benzene. Increased resistance to the hemolytic action of glycerol should be explored as a potentially useful biological monitoring procedure in the red blood cells of benzene-exposed humans.  相似文献   
48.
缺血性卒中或短暂性脑缺血发作患者的卒中预防指南   总被引:8,自引:0,他引:8  
这份新声明旨在为缺血性卒中或短暂性脑缺血发作存活者的缺血性卒中预防提供全面和及时的循证推荐,循证推荐包括对危险因素的控制,动脉粥样硬化性疾病的干预措施,心源性栓塞的抗栓治疗以及非心源性卒中抗血小板药的应用。另外,还为其他多种特殊情况下复发性卒中的预防提供了推荐、包括动脉夹层分离、卵圆孔未闭、高同型半胱氨酸血症、高凝状态、镰状细胞病、脑静脉窦血栓形成、女性卒中(特别是与妊娠和绝经后激素替代治疗相关卒中),脑出血后肮凝药的应用,以及该指南在高危人群中执行和应用的特殊措施。  相似文献   
49.
Nutritional deprivation is associated with poor growth and decreased levels of net circulating somatomedin activity, as measured by bioassay. Since somatomedin activity reflects the contributions both of somatomedins (which stimulate cartilage) and of somatomedin inhibitors (which antagonize the ability of the somatomedins to stimulate cartilage), we asked if changes in net somatomedin activity could involve progressive underlying alterations in levels of both somatomedins and somatomedin inhibitors. Groups of rats were killed during three days of fasting and 24 hours of refeeding. Fasting was associated with a rise in serum beta-hydroxybutyrate from 1.6 to 12.6 mmol/L after one day, followed by a decline to 4 mmol/L at three days. Somatomedins (low-MW) were separated from somatomedin inhibitors (high-MW) by gel permeation chromatography at acid pH on Sephadex G-50 and TSK-2000 HPLC. Somatomedins fell 35% after one day of fasting, and decreased to 59% below control levels after three days (P less than .05). Somatomedins did not change with six hours of refeeding, but then rose rapidly, reaching control levels after 24 hours. Somatomedins were correlated with change in weight (r = .41, P less than .05), but not with glucose or beta-hydroxybutyrate. Inhibitors rose to 195% above control-levels after one day of fasting, and continued to rise to 375% above control after three days (P less than .01). In contrast to the delayed change in somatomedins with refeeding, there was an abrupt fall in inhibitors (41% below three-day fasted levels after six hours), returning to control levels after 24 hours.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
50.
The comparative susceptibility of over 400 strains of aerobic and anaerobic pathogens, isolated from clinical specimens in late 1987 and early 1988, to imipenem and 15 other antimicrobial agents was studied using a uniform broth microdilution technique recommended by the National Committee for Clinical Laboratory Standards. Imipenem had the widest spectrum of activity and was consistently the most active agent tested. It was active against aerobic gram-positive cocci, aerobic gram-negative bacilli, and anaerobic bacteria.  相似文献   
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