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51.
The effects of alpha-tocopherol (50 mg/d) and beta-carotene (20 mg/d) supplementation on symptoms of chronic obstructive pulmonary disease were studied among the 29,133 participants of the Alpha-Tocopherol Beta-Carotene Cancer Prevention Study undertaken to investigate the effects of these two substances in the prevention of lung and other cancers. During the follow-up the supplementations did not affect the recurrence or incidence of chronic cough, phlegm, or dyspnea. The prevalence of chronic bronchitis and dyspnea at baseline was lower among those with high dietary intake of beta-carotene (OR = 0.78 and 0.67, respectively) or vitamin E (OR = 0.87 and 0.77) and high serum beta-carotene (OR = 0.59 and 0.62) and alpha-tocopherol (OR = 0.76 and 0.82). High intake and serum levels of retinol were associated with low prevalence of dyspnea (OR = 0.84 and 0.80, respectively) but not with chronic bronchitis. The results indicate no benefit from supplementation with alpha-tocopherol or beta-carotene on the symptoms of chronic obstructive pulmonary disorders but support the beneficial effect of dietary intake of fruits and vegetables rich in these compounds.  相似文献   
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Phosphatidylethanol (Peth) is formed in biological membranes when ethanol replaces water in the transphosphatidylation reaction catalyzed by phospholipase D. This charged lipid accumulates in the presence of ethanol, and it has unusual properties that can influence membrane structure and function. We have previously shown that dimyristoylphosphatidylethanol (DMPeth) and dipalmitoylphosphatidylethanol (DPPeth) form the interdigitated gel phase in the presence of Tris-HCl [O.P. Bondar, E.S. Rowe, Biophys. J., 71 (1996) 1440-1449]. In the present investigation, differential scanning calorimetry (DSC) and fluorescence have been used to investigate the effect of cholesterol on the phase behavior of DPPeth and DMPeth. Our results show that cholesterol prevents the formation of the interdigitated phase in the presence of Tris-HCl, and that ethanol counters this influence and restores the ability of these lipids to interdigitate. Pyrene-PC fluorescence probe was used in this investigation and gave results that were in agreement with the conclusions based on the DSC study.  相似文献   
53.
CONTEXT: Multiple comprehensive, risk-adjusted studies evaluating short-term surgical mortality have been reported previously. This report analyzes short-term and long-term outcomes, both nationally and at each individual transplant program, for all solid organ transplantations performed in the United States. OBJECTIVES: To report graft and patient survival rates for all solid organ transplantations, both nationally and at each specific transplant program in the United States, and to compare the expected survival rate with the actual survival rate of each individual program. DESIGN AND SETTING: Multivariate regression analysis of donor and recipient factors affecting graft and patient survival of all kidney, liver, pancreas, heart, lung, and heart-lung transplants reported to the United Network for Organ Sharing from 742 separate transplant programs. PATIENTS: A cohort of 97587 solid organ transplantations performed on 92966 recipients in the United States from January 1988 through April 1994. MAIN OUTCOME MEASURES: Short-term and conditional 3-year national and individual transplant program graft and patient survival rates overall and from 2 separate eras (era 1, January 1988-April 1992; era 2, May 1992-April 1994); comparison of actual center-specific performance with risk-adjusted expected performance and identification of centers with better-than-expected or worse-than-expected survival rates. RESULTS: One-year graft follow-up exceeded 98% and conditional 3-year follow-up exceeded 91% for all organs. Graft and patient survival improved significantly in era 2 compared with era 1 for all cadaver organs except heart, which remained the same. One-year cadaveric graft survival ranged from 81.5% for heart to 61.9% for heart-lung and 3-year conditional graft survival ranged from 91.3% for pancreas to 74.7% for lung. The percentage of programs whose actual 1-year graft survival was not different from or was better than their risk-adjusted expected survival ranged from 98.3% for heart-lung to 75.7% for liver. Most kidney, liver, and heart programs whose actual survival was significantly less than expected performed small numbers (less than the national average) of transplantations per year. CONCLUSIONS: Graft and patient survival for solid organ transplantations showed improvement over time. Conditional 3-year graft and patient survival rates were approximately 90% for all organs except for lung and heart-lung. The conditional 3-year survival rates were better than 1-year survival rates, indicating the major risk after transplantation occurs in the first year. The majority of transplant programs achieved actual survival rates not significantly different from their expected survival rates. Center effects were most significant within the first year after transplantation and had much less influence on long-term survival outcomes.  相似文献   
54.
PURPOSE: To study the course and visual outcome of Vogt-Koyanagi-Harada (VKH) syndrome in children. METHODS: The medical records of 97 consecutive patients with VKH syndrome were reviewed. Patients had been seen at King Khaled Eye Specialist Hospital in Riyadh, Saudi Arabia. The records were divided into two groups: those in whom the onset of the disease occurred at the age of 14 years or younger (pediatric group) and those in whom the disease manifested after the age of 14 years (adult group). RESULTS: Eight (61%) of the 13 children required cataract surgery compared to 14(17%) of 84 adult patients. Despite medical and surgical therapy, eight (61%) of the pediatric group had a final visual acuity of 20/200 or worse compared with 22 (26%) of the 84 adult patients (p=0.0103). CONCLUSION: The course of early-onset VKH (before the age of 14 years) appears to be aggressive. The ocular complications are more severe in children than in adults, leading to rapid deterioration in vision. Despite therapy, the final visual outcome of VKH in children is poor.  相似文献   
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Ductal carcinoma in situ (DCIS) is considered a direct precursor of invasive ductal breast cancer (IDC). We combined tissue microdissection and comparative genomic hybridization to identify genetic changes in five DCIS lesions with no invasion and in two that were adjacent to IDC. Extensive genetic changes characterized pure DCIS cases with gains of 1q, 6q, 8q, and Xq as well as losses of 17p and chromosome 22 being most often involved. Except for the Xq gain, these changes are also common to IDC. Separate analysis of DCIS and IDC components in the same tumor revealed an almost identical pattern of genetic changes in one case, whereas substantial differences were found in another. We conclude that many of the common genetic changes in IDC may take place before development of invasive growth. However, a simple linear progression model may not always account for the DCIS-IDC transition.  相似文献   
58.
OBJECTIVE: To determine the outcome of DSM-III-R schizophreniform disorder with good prognostic features. METHOD: A 6-year follow-up of 20 cases was conducted with structured interviews (comprehensive assessment of symptoms and history) and assessments of functioning scales (global assessment of functioning, Strauss-Carpenter Scale). RESULTS: Thirty-five percent of the cases had major affective disorders, 35% had schizophreniform episodes and major affective disorders, 5% had schizophreniform episodes only, 10% developed schizophrenia, and 15% had no disorders. CONCLUSION: The findings suggest an association between schizophreniform disorder with good prognostic features and affective illness.  相似文献   
59.
PURPOSE: While advanced cardiac life support (ACLS) training is widely available, it is not mandatory for all anaesthetists. We hypothesised that adherence to ACLS guidelines during resuscitation of ventricular fibrillation (VFib) as assessed in a simulator environment would be poor by anaesthetists not trained in ACLS compared with those who had received training. METHODS: With approval by the ethics review board, 89 subjects participated in the study. The simulation system consisted of a computer controlled mannequin with lifelike qualities set in a mock operating room. Each subject was given a test scenario that contained several standard anaesthetic problems. A VFib cardiac arrest occurred after approximately one hour into the simulation. A perfect score (score = A) defined complete compliance with the ACLS guidelines, whereas minor deviations (score = B) included changes in energy levels, drug doses or treatment order. The failure to discontinue the anaesthetic, defibrillate or administer epinephrine were considered major deviations (score = C). RESULTS: Eight subjects followed the ACLS guidelines (9%, score = A), while 27 subjects showed minor (30%, score = B) and 54 subjects major deviations (61%, score = C). Sixty-two of the 89 participants (70%) had taken the ACLS course and achieved higher scores than did anaesthetists without such training (P < 0.05). Forty-two participants (47%) did not discontinue the anaesthetic, 10 (11%) never gave epinephrine and 5 (6%) never used the defibrillator. CONCLUSION: Adherence to ACLS guidelines was poor. A greater proportion of subjects without previous ACLS training had deviations from protocol than did subjects who had received training. We need to consider ways to ensure that anaesthetists obtain and retain resuscitation skills according to ACLS guidelines.  相似文献   
60.
The impact of oral treatment with insulin on disease development was studied in diabetes prone BB rats. Because of the positive outcome of a prior study in non obese diabetic (NOD) mice, BB rats received insulin in combination with a bacterial adjuvant. Porcine insulin was given orally twice weekly from 35-100 days of age, the E. coli preparation OM-89 was fed on alternate days. Other groups received vehicle, the bacterial adjuvant, or insulin alone. Both insulin containing oral dosing regimens induced a transient non significant delay in diabetes onset. Insulin alone, however did not decrease the final diabetes incidence. Oral dosing with insulin plus adjuvant caused exacerbation of disease development as judged from the decreased survival rate in comparison with the insulin treated group (p < 0.05). Intra-islet infiltration also increased (p < 0.005) compared with the insulin or vehicle treated groups. The effect correlated with enhanced interferon gamma (IFNgamma) and decreased interleukin 10 (IL-10) gene expression in the gut suggesting a shift towards proinflammatory T helper 1 (Th1) reactivity (p < 0.01). Although treatment with adjuvant alone also increased the degree of insulitis, an enhanced incidence of diabetes and a shift in cytokine expression was only seen in the group receiving insulin plus adjuvant. Taken together, the data suggest that treatment with a bacterial adjuvant and oral insulin may alter the gut immunoregulatory state such that disease promoting rather than protective immune responses are induced.  相似文献   
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