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71.
Maintaining and improving the quality of care is central to the Health Security Act, according to this in-depth analysis of the Act's intended quality reforms. The author reviews the proposal from several perspectives, including those of administrative law, hospital administration, health services research, and risk management. In the author's opinion, quality reforms involving the federal government as purchaser of medical care and as grader of the quality of its health care providers require close scrutiny. The establishment of a National Health Board and a National Quality Management Council further heightens concerns for quality standards and oversight. The article also evaluates the proposed health quality data super-highway, making several stops for contemplation and critical analysis.  相似文献   
72.
OBJECTIVE: To examine type of care, oral health status and service patterns by country of birth and language. METHODS: A random sample of public-funded patients (n = 6, 109) was surveyed in 1995-96. RESULTS: Emergency care was highest among overseas-born patients who spoke a non-English language at home; edentulism was highest among Australian-born/English only patients; while a higher percentage of Australian-born persons were in the periodontal health category (chi 2; p < 0.05). Differences in caries experience were generally small (ANOVA; p < 0.05). Service provision varied by country of birth/language after controlling for socio-demographic characteristics, type of care, and oral health status in six service areas (logistic regression; p < 0.05). CONCLUSIONS: Service patterns may reflect behavioural and cultural factors of patients or providers operating independently of socio-demographic and oral health status variables. IMPLICATIONS: Variation and potential inequality in service patterns related to cultural factors existed within a group of disadvantaged patients.  相似文献   
73.
OBJECTIVE: To identify the pathologic features of prognostic significance in patients with resectable adrenocortical carcinomas. DESIGN: Retrospective review. SETTING: Tertiary referral center. PATIENTS: Review of the Memorial Sloan-Kettering Cancer Center prospective adrenocortical carcinoma database from 1986 through 1996 identified 46 patients who underwent curative adrenalectomy for primary disease. All cases were reviewed by a single pathologist and each primary tumor was characterized by 16 separate pathologic parameters. MAIN OUTCOME MEASURE: Overall survival rates in the patient population. RESULTS: The 5-year overall survival rate for the entire cohort was 36% (median survival rate, 28 months). Of the pathologic factors analyzed, tumor size, number of mitotic figures, and the presence of intratumoral hemorrhage were independent prognostic factors. Patients presenting with primary tumors larger than 12 cm (n = 30) had a worse outcome compared with those with smaller tumors (n = 16) (5-year survival rate: 53% vs. 22%, P<.05). Mitotic count (> or =6 per 10 high-power fields) was a negative prognostic feature (n = 15) with a 5-year survival rate of 13% vs. 51% for 0 to 6 mitotic figures per 10 highpower fields (n = 31, P<.05). Intratumoral hemorrhage (n = 23) was also a negative prognostic factor compared with no evidence of intratumoral hemorrhage (n = 23) (5-year survival rate, 53% vs. 22%, P<.05). Overall survival rates were also calculated based on the number of pathologic risk factors. Patients with no risk factors had an 83% 5-year survival rate, which decreased to 42% with 1 factor, 33% with 2 factors, and 0% with all 3 risk factors. CONCLUSIONS: Tumor size, hemorrhage, and mitotic count correlate with survival rates for patients undergoing curative resection. Based on these pathologic factors, adrenocortical carcinomas may be divided into low- and high-risk groups.  相似文献   
74.
We have isolated and sequenced the mouse preprodynorphin gene (Pdyn). The Pdyn gene can encode for six biologically active dynorphin peptides. The predicted mouse preprodynorphin has 90%, 67%, and 66% identity with the predicted rat, porcine, and human preprodynorphins, respectively. Using an RT-PCR technique, we show that the Pdyn gene starts being expressed at embryonic day 12.5, with a steep increase of expression by embryonic day 14.5; in the adult mouse it is expressed in the brain, but not in liver, heart, spleen, or kidney.  相似文献   
75.
BACKGROUND: FK506 is a recently developed immunosuppressant that has been useful in improving the survival of transplanted organs. Among the numerous adverse side effects of FK506, thrombotic microangiopathy (TMA) stands out as an infrequent but severe complication. METHODS: We report two cases of FK506-associated TMA and review the 19 previous reported cases. RESULTS: From these 21 cases, the reported incidence of FK506-associated TMA is between 1% and 4.7%. It is more frequent in females, and the mean age at presentation is 47 years. Eighty-one percent of the cases occurred in patients with kidney allografts, and the remaining patients had liver, heart, or bone marrow transplants. Clinically, TMA was diagnosed at an average interval of 9.3 months from the time of transplantation. Patients may be asymptomatic or may present with the full-blown picture of hemolytic uremic syndrome. All patients had an elevated serum creatinine level but did not always show signs of hemolysis. Trough levels of FK506 were not predictive for the development of TMA, but generally a reduction of drug dose correlated with kidney function improvement and disappearance of the hemolytic picture. The renal allograft biopsy provided a conclusive diagnosis in all 17 cases in which this procedure was performed. Treatment, which mainly consisted of reduction or discontinuation of FK506, anticoagulation, and/or plasmapheresis with fresh-frozen plasma exchange, resolved TMA in most patients (57%). However, in one of these patients (5%), the graft was subsequently lost due to causes unrelated to TMA, such as acute or chronic rejection. Despite treatment, one patient (5%) lost the graft due to acute rejection and persistent TMA, and three other patients (14%) who had bone marrow, heart, and liver transplants, died of multiple organ failure, probably unrelated to TMA. In the remaining four patients (19%), response to treatment was not reported. CONCLUSIONS: TMA must be considered in organ transplant patients treated with FK506 whenever kidney function deteriorates, even in the absence of microangiopathic hemolytic anemia. Although TMA usually responds to treatment, it may, in rare cases, lead to loss of kidney function or even the patient's death.  相似文献   
76.
The D2 peptide derived from an S. aureus fibronectin-binding protein (FnBP) was expressed on the surface of the icosahedral cowpea mosaic virus (amino acids 1-30 of D2) or on the rod-shaped potato virus X (amino acids 1-38 of D2), termed CPMV-MAST1 and PVX-MAST8, respectively. Mice and rats were immunized subcutaneously with CPMV-MAST1 and mice with PVX-MAST8 in adjuvant and high titres of FnBP-specific antibody were obtained. The mouse IgG was predominantly of the IgG2a and IgG2b isotypes, which strongly bound complement component C1q, suggesting a TH1-bias in the peptide-specific responses. Sera from mice and rats immunized with CPMV-MAST1 and from mice immunized with PVX-MAST8 were shown to completely inhibit the binding of fibronectin to immobilised recombinant FnBP and rat sera against CPMV-MAST1 were able to block adherence of S. aureus to fibronectin. These studies demonstrate that the D2 peptide is highly immunogenic when expressed on 2 different plant viruses and highlight the potential of plant virus-based vaccines to protect against S. aureus infections.  相似文献   
77.
In April 1998 an outbreak of salmonellosis amongst guests at a wedding feast was investigated. Of the 58 attendees interviewed 38 (66%) subsequently developed gastrointestinal symptoms. Stool cultures from 7 cases grew Salmonella Typhimurium RDNC A045. Food samples were culture-negative for Salmonella spp. A cohort study implicated spatchcock (RR 2.5, 95% CI 1.09-5.77) and scampi (RR 2.0, 95% CI 1.05-3.89). Temperature abuse and cross-contamination within the kitchen during preparation and cooking are likely to have been the main contributing factors to this outbreak. Control measures included staff education in safe food handling and improvements in poultry processing methods to minimise carcass contamination.  相似文献   
78.
In a simulated field trial Bacillus thuringiensis var israelensis (BTI) pellet formulation exhibited an enhanced efficacy with increasing dose. A dosage of 1.0 and 1.5 ppm was most effective under simulated field conditions. In field trials persistence of BTI pellet (1.0 ppm) was observed for 35 days in moderately polluted water collection as compared to 21 days in highly polluted water bodies.KEY WORDS: Bacillus thuringiensis, Malaria, Mosquito control  相似文献   
79.
Objectives: The purpose of this study was to examine gender and ethnic differences in survival of persons receiving treatment for HIV infection to determine if differences existed, and if they did, to assess the possibility of explaining these differences by examining other factors, such as age, disease severity when beginning treatment, alcohol, illicit drugs, tobacco, educational level, living arrangements, antiretroviral treatment, PCP prophylaxis, sexually transmitted diseases, mode of transmission and opportunistic infections.

Design: A retrospective cohort study of all clients receiving treatment at an HIV only clinic from its opening in early 1988 until the end of May 1993. Statistical methods used to examine the data included incidence density ratios, Kaplan‐Meier survival curves, Breslow (generalized Wilcoxon) tests of equality of survival curves and Cox proportional hazards models both with and without time dependent covariates.

Results: In the cohort (37% African American, 7% Hispanic American and 25% female), 220 deaths occurred during 1223 person years of follow‐up. Compared to European American males, the following incidence density ratios were observed: European American females: 0.50, Hispanic American females: 0.70, Hispanic American males: 0.96, African American females: 1.28 and African American males: 2.38. The differences were noted above for gender/ethnicity groups were significant at the p < 0.0001 level. After adjusting for disease stage (as measured by laboratory testing of CD4 positive T‐lymphocytes), educational level, and age, no differences in survival by gender or ethnicity remained. Disease stage and educational level had the greatest prognostic significance.

Conclusions: European Americans entered treatment at a much earlier disease stage (as measured by CD4 positive T‐lymphocyte counts) and had higher educational levels (a surrogate for socioeconomic status) than African Americans. These factors may explain the longer survival in European Americans as compared to African Americans in this cohort.  相似文献   

80.
Creutzfeldt-Jacob disease manifests clinically as a form of presenile dementia. It is now known to be caused by a transmissible agent, probably a "slow virus". Rapidly progressive atrophic changes on serial computed tomograms of the brain are highly suggestive of the disease. Neuroradiographic and pathological findings in two cases of Creutzfeldt-Jacob disease are documented.  相似文献   
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