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71.
"Hyperacute" renal-homograft rejection in man   总被引:25,自引:0,他引:25  
  相似文献   
72.
PURPOSE: To assess internal medicine and general surgery residents' attitudes about the effects of the Accreditation Council for Graduate Medical Education duty hours regulations on medical errors, quality of patient care, and residency experiences. METHOD: In 2005, the authors surveyed 200 residents who trained both before and after duty hours reform at six residency programs (three internal medicine, three general surgery) at five academic medical centers in the United States. Residents' attitudes about the effects of the duty hours regulations on the quality of patient care, residency education, and quality of life were measured using a survey instrument containing 19 Likert scale questions on a scale of 1 to 5. Survey responses were compared using the Student's t-test. RESULTS: The response rate was 80% (159 residents). Residents reported that whereas fatigue-related errors decreased slightly, errors related to reduced continuity of care significantly increased. Additionally, duty hours regulations somewhat decreased opportunities for formal education, bedside learning, and procedures, but there was no consensus that graduates would be less well trained after duty hours reform. Residents, particularly surgical trainees, reported improvements in quality of life and reduced burnout. CONCLUSIONS: Residents in medicine and surgery had similar opinions about the effects of duty hours reform, including improved quality of life. However, resident opinions suggest that reduced fatigue-related errors have been offset by errors related to decreased continuity of care and that the quality of the educational experience may have declined. Quantifying the degree to which regulating duty hours affected errors related to discontinuity of care should be a focus of future research.  相似文献   
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Nucleotide sequence of the geminivirus chloris striate mosaic virus   总被引:6,自引:0,他引:6  
The genome of chloris striate mosaic virus (CSMV) comprises a single circular DNA as determined by analyses on virion single-stranded (ss) DNA and virus-specific covalently closed circular (ccc) DNA isolated from infected plants. The nucleotide sequence of CSMV DNA was determined from cccDNA and the data were accommodated into one DNA circle of 2750 nucleotides. Comparison of the nucleotide sequence with those of maize streak virus (MSV), wheat dwarf virus (WDV), and digitaria streak virus (DSV) showed 49, 47, and 48% DNA homology, respectively. The sequence has four potential open reading frames for proteins of greater than 10,000 mol wt, two in the viral (+) sense and two in the complementary (-) sense. Three of these potential coding regions have homologous counterparts, by comparison of the amino acid sequences, among the open reading frames reported for MSV, WDV, and DSV. CSMV encapasidates primer molecules able to prime the synthesis in vitro of a complementary strand to virion DNA, initiating this reaction at one site on the genome. The CSMV primer comprising approximately 88 nucleotides was located within the smaller of two intergenic or noncoding regions.  相似文献   
78.
The incidence of HL-A8 was significantly increased in 64 Caucasian patients with thyrotoxicosis compared with 700 Australian blood donors (42% versus 24%). No significant correlation was observed between HL-A8 and autoantibodies to thyroid components in thyrotoxic patients; thus the association of HL-A8 must be either with the disease itself, or possibly with immune responses not tested for this study.  相似文献   
79.
Brain matrix metalloproteinase 1 levels are elevated in Alzheimer's disease   总被引:3,自引:0,他引:3  
Several lines of evidence indicate that there may be an inflammatory component to the pathology of Alzheimer's disease (AD), the major form of degenerative dementia in the elderly. Activity of inflammatory cells, and the elaboration of toxic molecules by such cells may be a significant factor in disease progression. In peripheral inflammatory states, the increased activity of matrix metalloproteinase (MMP) enzymes are a major cause of tissue breakdown and secondary damage in diseases such as rheumatoid arthritis. The activity of such enzymes in the normal or diseased central nervous system is, however, not well characterized. We have therefore determined the levels of MMP 1 (collagenase) in the normal human brain and in AD. MMP1 levels were relatively low though were significantly elevated by approximately 50% in AD in all cortical areas examined. Given the activity towards collagen of MMP1, it is possible that enhanced MMP1 activity in AD, may contribute to the blood-brain barrier dysfunction seen in AD.  相似文献   
80.
Hereditary canine spinal muscular atrophy (HCSMA) is a dominantly inherited motor neuron disease that produces muscle weakness and atrophy. Immunocytochemical and computer-imaging morphometric methods were used to compare early changes that occurred in dogs with HCSMA (n = 4) versus controls (n = 2). The size and number of neurons in the ventral horn and the number of motor neurons expressing choline acetyltransferase were quantitated. The density of all ventral horn neurons per micrometer squared in dogs with HCSMA was greater than controls, and there were more small neurons than in controls. Immunocytochemical methods revealed more small cholinergic neurons and fewer large cholinergic neurons in HCSMA than in controls, suggesting growth arrest in HCSMA or a shift in size class from large cholinergic neurons to small ones. The density of cholinergic neurons per micrometer squared was not significantly different between the two groups. Analysis of predicted distributions of cholinergic and noncholinergic neurons revealed that HCSMA cholinergic neurons were smaller and that, in some size classes, fewer neurons expressed choline acetyltransferase. These observations indicate that in HCSMA the motor neuron fails to achieve normal size and/or undergoes atrophy.  相似文献   
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