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121.
This study compares two North American time-activity data bases: the National Human Activity Pattern Survey (NHAPS) of 9386 interviewees in 1992-1994 in the continental USA with the Canadian Human Activity Pattern Survey (CHAPS) of 2381 interviewees in 1996-1997 in four major Canadian cities. Identical surveys and methodology were used to collect this data: random sample telephone selection within the identified telephone exchanges, computer-assisted telephone interviews, overselection of children and weekends in the 24-h recall diary and the same interviewers. Very similar response rates were obtained: 63% (NHAPS) and 64.5% (CHAPS). Results of comparisons by age within major activity and location groups suggest activity and location patterns are very similar (most differences being less than 1% or 14 min in a 24-h day) with the exception of seasonal differences. Canadians spend less time outdoors in winter and less time indoors in summer than their U.S. counterparts. When exposure assessments use time of year or outdoor/indoor exposure gradients, these differences may result in significant differences in exposure assessments. Otherwise, the 24-h time activity patterns of North Americans are remarkably similar and use of the combined data set for some exposure assessments may be feasible.  相似文献   
122.
Avasimibe Pfizer     
Avasimibe (also known as CI-1011 or PD-148515) is a selective acyl-coenzyme A:cholesterol O-acyltransferase (ACAT) inhibitory lipid-regulating agent under development by Pfizer (formerly Parke-Davis) for the potential treatment of hyperlipidemia and atherosclerosis. The compound is currently undergoing phase III clinical trials [371470].  相似文献   
123.
Burnett L 《Lancet》2003,362(9397):1761-1762
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124.
A 53-year-old man with human-immunodeficiency-virus infection presents with a 2-year history of nodules on the extensor surfaces of his extremities. A biopsy confirmed the diagnosis of erythema elevatum diutinum. The clinical presentation, histopathology, etiology, and treatment options are reviewed.  相似文献   
125.
A 55-year-old man with psoriasis presented with erythematous, edematous plaques, tense bullae, and erosions. Direct immunofluorescence and histopathologic examination confirmed the diagnosis of bullous pemphigoid. Both dermatologic conditions responded to azathioprine. The clinical presentation, etiology, and treatment options are reviewed.  相似文献   
126.
PURPOSE: Ischemia-reperfusion injury is a relatively common cause of renal tubular cell death and acute renal failure. While nuclear factor-kappaB has been implicated in the pathophysiology of renal ischemia-reperfusion injury, the effect of nuclear factor-kappaB inhibition on ischemia induced renal tubular cell death remains unknown. MATERIALS AND METHODS: Renal tubular cells (LLC-PK1) were exposed to simulated ischemia in the presence or absence of 10 microM. pyrrolidine dithiocarbamate (nuclear factor-kappaB inhibitor). Nuclear factor-kappaB activation (electrophoretic mobility shift assay and immunohistochemistry) and the effect of pyrrolidine dithiocarbamate on nuclear factor-kappaB activation (electrophoretic mobility shift assay) and ischemia induced apoptosis (terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling) were determined. RESULTS: Simulated ischemia induced nuclear factor-kappaB activation and renal tubular cell apoptosis versus controls (mean plus or minus standard error of mean 62 +/- 5.2 versus 0.4 +/- 0.3 apoptotic nuclei per high power field, p <0.05). In contrast, previous cellular exposure to pyrrolidine dithiocarbamate effectively inhibited nuclear factor-kappaB activation and prevented ischemia induced apoptosis (mean 14 +/- 6 apoptotic nuclei per high power field). CONCLUSIONS: Simulated ischemia induces nuclear factor-kappaB intranuclear translocation and activation in renal tubular cells. Furthermore, nuclear factor-kappaB mediates ischemia induced renal tubular cell apoptosis. Further elucidation of the complex role of nuclear factor-kappaB in inflammatory injury may lead to the development of targeted therapeutic strategies that ameliorate ischemic renal injury.  相似文献   
127.
128.
This study assessed the role of a novel fibrin sealant (Vivostat in adhesion reduction after flexor tendon surgery. The deep flexor tendons of the 2nd and 4th digits of the left paw of 20 rabbits were exposed and a standard partial injury was performed on each. The rabbits were randomized to either immediate post-injury treatment with Vivostat or no treatment. In each case active movement of the 2nd digit was prevented while the 4th digit was allowed to move normally. The two groups were assessed at 14 days for adhesion formation with a tensiometer. The right paw acted as the unoperated control. Results showed that there was no significant difference in the force needed to remove the tendon from its sheath when comparing the two Vivostat((R))-treated groups to the unoperated controls. There was, however, a highly significant difference in this force between the non-Vivostat-treated groups and the unoperated controls. This suggests a beneficial effect of Vivostat in reducing post surgical tendon adhesion formation.  相似文献   
129.
BACKGROUND: Livestock farmers are more likely to be exposed to a variety of different farming hazards than crop farmers. An analysis of occupation and industry-coded U.S. death certificate data from 26 states for the years 1984-1993 was conducted to evaluate mortality patterns among crop and livestock farmers. METHODS: Cause-specific proportionate mortality ratios (PMRs) were calculated using a National Institute for Occupational Safety and Health (NIOSH) computer program designed to calculate sex and race specific PMRs for occupations and industries in population-based data. RESULTS: Among white male (WM) livestock farmers, there was a significantly higher mortality from cancer of the pancreas, prostate and brain, non-Hodgkin's lymphoma (NHL), multiple myeloma, acute and chronic lymphoid leukemia, and Parkinson's disease. WM crop farmers showed significantly higher mortality risk for cancer of the lip, skin, multiple myeloma, and chronic lymphoid leukemia. CONCLUSIONS: These disease trends suggested that livestock farmers might be exposed to more carcinogens or agricultural chemicals than crop farmers.  相似文献   
130.
The gene causing hereditary hemochromatosis (HH), HFE is an HLA class I-like gene with no known immunological function but indirectly related to the immune functions because of its role in iron transport. It is located 6.5 Mb telomeric to HLA-A. The most common mutation of HFE, C282Y, has a Celtic origin and most patients with HH are homozygous for it in Northern European populations. While there is an enormously increased risk for hepatocellular cancer in hemochromatosis that is attributed to the toxic effects of iron, the risk for extra-hepatic cancers is also increased slightly. Recent studies have found genetic associations between several cancers and C282Y but only in the presence of a particular allele of the transferrin receptor gene. This suggests that the increased cancer risk is more likely due to the effects of iron. In childhood acute lymphoblastic leukemia (ALL), however, there is a strong association of C282Y with a gender effect in two different Celtic populations. This association does not require homozygosity for C282Y or an interaction with the transferrin receptor gene, and is male-specific. The other HFE mutation H63D does not confer increased risk to childhood ALL. Acute myeloblastic leukemia and Hodgkin's disease in adults do not have an association with HFE. Its male-specificity, occurrence in childhood and the lack of a gene-dosage effect suggest that the C282Y association in childhood ALL may reflect the involvement of another HLA-linked gene in leukemia susceptibility.  相似文献   
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