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81.
BACKGROUND & AIMS: Hepatitis B virus (HBV) genotypes may be related to severity of liver disease and treatment response. The aims of this nationwide study were to determine the prevalence of HBV genotypes in the United States and the association between HBV genotypes and patient demographics, mode of infection, and clinical status. METHODS: A total of 694 consecutive chronic HBV-infected patients seen in 17 U.S. liver centers during a 1-year period were enrolled. Demographic, clinical, and laboratory data were collected. Sera were tested for HBV genotyping, precore, and core promoter variants by line-probe assays. RESULTS: All 7 HBV genotypes (A-G) were found, with genotypes A and C the most common. The prevalence of HBV genotypes was different in different regions of the United States. A strong correlation was found between HBV genotypes and ethnicity. HBV genotype A was prevalent among white and black patients, whereas genotypes B and C were most common among Asian patients. The predominant genotype among patients born in the United States, Europe, the Far East, and Southeast Asia were A, D, C, and B, respectively. Genotypes A and C were associated with a higher prevalence of hepatitis B e antigen. Precore variant was detected in 27% of patients and core promoter variant in 44% of patients. CONCLUSIONS: Our study suggests that the epidemiology of HBV infection in the United States may have changed over time as a result of immigration from countries with a high prevalence of HBV infection. HBV genotypes may account for the heterogeneity in disease manifestations among patients with chronic HBV infection.  相似文献   
82.
Liver Transplantation for Uncontrollable Variceal Bleeding   总被引:1,自引:0,他引:1  
Objectives: A small number of liver transplant candidates experience variceal bleeding that cannot be controlled by standard medical therapy. The objective of this study was to analyze the role of urgent liver transplantation for this subset of patients with acute, refractory, portal hypertensive bleeding. Methods: Retrospective review of data from 416 patients undergoing 449 liver transplantations between March, 1988 and February, 1993 revealed seven patients (1.7%) with endstage liver disease who underwent transplantation for uncontrollable variceal bleeding. All patients failed therapy with intravenous pitressin, endoscopic sclerotherapy, balloon tamponade, and/or transjugular intrahepatic portosystemic shunt and continued to bleed. Patients ranged in age from 6 months to 56 years. All patients were Child's class C. Two patients were listed for transplantation with the United Network for Organ Sharing as status 3, and five patients were listed as status 4. Results: All patients underwent successful liver transplantation with immediate control of bleeding. One patient expired on the 26th postoperative day from multiple organ failure, and another patient expired with recurrent hep-atocellular carcinoma on the 110th postoperative day. No patients experienced late rebleeding from varices after transplantation. Conclusions: Urgent liver transplantation is effective and feasible for the small subset of patients with uncontrollable variceal bleeding and endstage liver disease. Prompt and complete evaluation of the potential recipient and availability of a donor organ are critical to the success of this approach.  相似文献   
83.
OBJECTIVES: Assessment of health-related quality of life (HRQOL) outcomes in studies of liver disease and liver transplantation is necessary. Reliable and valid disease-targeted HRQOL measures are thus needed. The objective of this study was to develop a reliable and valid self-report HRQOL instrument for ambulatory adults with chronic liver disease. METHODS: The Liver Disease Quality of Life instrument, LDQOL 1.0 (an HRQOL measure that uses the SF-36 as a generic core and 12 disease-targeted multi-item scales) was administered in a multicenter, cross-sectional field test to 221 ambulatory adults with advanced, chronic liver disease referred for primary liver transplantation evaluation. Disease-targeted scales included liver disease-related symptoms, liver disease-related effects on activities of daily living, concentration, memory, sexual functioning, sexual problems, sleep, loneliness, hopelessness, quality of social interaction, health distress, and self-perceived stigma of liver disease. We estimated the internal consistency reliability (Cronbach's alpha) for multi-item scales and construct validity. RESULTS: Interial consistency reliability coefficients were excellent, ranging from 0.62 to 0.95, with 19 of 20 scales >0.70. Multitrait scaling analysis provided strong support for item discrimination across scales, and exploratory factor analysis demonstrated distinguishable physical, mental, and social health dimensions. Significant associations were found between worse HRQOL and worse Child-Pugh class, worse self-rated liver disease severity, and increased number of disability days. CONCLUSIONS: The results of this multicenter field test provide support for the reliability and validity of the LDQOL 1.0 as an HRQOL outcome measure for individuals with chronic liver disease.  相似文献   
84.
Erythroid failure in Diamond-Blackfan anemia is characterized by apoptosis   总被引:2,自引:4,他引:2  
Perdahl  EB; Naprstek  BL; Wallace  WC; Lipton  JM 《Blood》1994,83(3):645-650
Programmed cell death, also known as apoptosis, is frequently initiated when cells are deprived of specific trophic factors. To investigate if accelerated apoptosis contributes to the pathogenesis of Diamond- Blackfan anemia (DBA), a rare pure red blood cell aplasia of childhood, we studied the effect of erythropoietin (epo) deprivation on erythroid progenitors and precursors from the bone marrow of DBA patients as compared with hematologically normal controls. Apoptosis in response to epo deprivation was evaluated by enumeration of colony-forming unit- erythroid (CFU-E)- and burst-forming unit-erythroid (BFU-E)-derived colonies in plasma clot semisolid culture and by the identification of typical DNA oligosomes by gel electrophoresis from marrow mononuclear cells in liquid culture. In all DBA patients there was a marked decrease in CFU-E- and BFU-E-derived colony formation compared with normal controls at comparable time points of epo deprivation, with a complete loss of CFU-E-derived colonies in semisolid culture by 9 hours of epo deprivation versus 48 hours in controls. The BFU-E-derived colony response to epo deprivation displayed a similar pattern of decrement. Apoptotic changes assessed by the presence of characteristic DNA fragmentation began in the absence of epo deprivation and were readily detected within 3 hours of epo deprivation in DBA cultures versus 9 hours in controls. We conclude that DBA is characterized by accelerated apoptosis as measured by the loss of erythroid progenitor clonogenicity and increased progenitor and precursor DNA fragmentation leading to the formation of characteristic oligosomes, consistent with an intrinsic erythroid-progenitor defect in which increased sensitivity to epo deprivation results in erythroid failure.  相似文献   
85.
BACKGROUND & AIMS: Constitutive expression of cyclooxygenase 2 (COX-2) has been found in 85% of colorectal cancers. Ras mutations are found in 50% of colorectal adenocarcinomas. The aim of this study was to determine the role of COX-2 in ras-induced transformation in rat intestinal epithelial (RIE) cells. METHODS: Cell growth was determined by cell counts. The expression of COX-2 was examined by Northern and Western analyses. For tumorigenicity assays, cells were inoculated into dorsal subcutaneous tissue of athymic nude mice. DNA-fragmentation assays were performed to detect apoptosis. RESULTS: The expression of COX-2 was increased in RIE-Ras cells at both messenger RNA (9-fold) and protein (12-fold) levels. Prostaglandin I2 levels were elevated 2.15-fold in RIE-Ras cells. Serum deprivation further increased COX-2 expression 3.8-fold in RIE-Ras cells. Treatment with a selective COX-2 antagonist (SC58125) inhibited the growth of RIE-Ras cells through inhibition of cell proliferation and by induction of apoptosis. SC-58125 treatment reduced the colony formation in Matrigel by 83.0%. Intraperitoneal administration of SC-58125 suppressed RIE-Ras tumor growth in nude mice by 60.3% in 4 weeks. SC-58125 treatment also induced apoptosis in RIE-Ras cells as indicated by increased DNA fragmentation. CONCLUSIONS: Overexpression of COX-2 may contribute to tumorigenicity of ras-transformed intestinal epithelial cells. Selective inhibition of COX-2 activity inhibits growth of ras-transformed intestinal epithelial cells and induces apoptosis. (Gastroenterology 1997 Dec;113(6):1883-91)  相似文献   
86.
Damage-control surgery and open-abdomen is an acceptable—and often lifesaving—approach to the treatment of patients with severe trauma, abdominal compartment syndrome, necrotizing soft tissue catastrophes, and other abdominal disasters, when closing the abdomen is not possible, ill advised, or will have serious sequelae. However, common consequences of open-abdomen management include large abdominal wall defects, enterocutaneous fistulas (ECFs), and enteroatmospheric fistulas (EAFs). Furthermore, in such patients, a frozen and hostile abdomen (alone or combined with ECFs) is not uncommon. Adding biologic mesh to our surgical armamentarium has revolutionized hernia surgery.  相似文献   
87.

Background

The rehabilitation of older patients in Ireland after an acute medical event occurs at dedicated onsite hospital units or at offsite centres. Information on medical complications and outcomes is inadequate.

Aims

Enumeration of medical complications of patients admitted to a dedicated onsite rehabilitation unit for older people, and the extent of co-morbidity in the population with the effects that this had on the evolution of medical complications.

Methods

A retrospective analysis of patients admitted to a 58-bed onsite unit over a 1-year period was performed. Information collating co-morbidities, medical complications and functional outcomes was recorded.

Results

Medical complications occurred in almost 95 % of patients, where full data were available. Over one-third required intravenous therapy.

Conclusion

Twenty-four hour medical cover is required for older patients managed at onsite rehabilitation units. Further studies on offsite medical rehabilitation facilities for older patients are required.  相似文献   
88.
89.
90.
Juvenile amyopathic dermatomyositis   总被引:1,自引:0,他引:1  
We report a 15-year-old girl with a 10-year-old history of typical skin features of dermatomyositis (DM) without evidence of muscle involvement. Amyopathic dermatomyositis(ADM) is defined by the presence of biopsy confirmed classic cutaneous findings of dermatomyositis in the absence of any clinical or laboratory signs of muscle disease for at least 2 years after onset of skin pathology. To exclude muscle involvement muscle enzymes should be normal; moreover additional use of magnetic resonance imaging and muscle ultrasound is currently being proposed. It is as yet undetermined. whether early aggressive immunosuppressive treatment of ADM might prevent the development of myositis at a later date or influence the course of the skin disease. In a paediatric patient with ADM we advocate a more expectant attitude with careful and regular monitoring for possible development of muscle disease.  相似文献   
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