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991.
The changes in nasal function which occur after septorhinoplasty for obstruction were investigated by anterior rhinomanometry in 15 subjects. Objective and subjective measures of outcome were compared. Anterior rhinomanometry was performed after nasal decongestion. These data were mathematically transformed to determine the amount of airflow asymmetry through the nostrils and the stiffness of the nasal valve. The results suggested that the presence of gross airflow asymmetry (> +/- 80%) in patients prior to surgery was a bad prognostic indicator for post-operative satisfaction with the airway. Patient satisfaction with function and cosmetic appearance post-operatively was correlated with the presence of symmetrical nasal airflow. Nasal valve stiffness did not seem to be affected by septorhinoplasty.  相似文献   
992.
Oil emulsion and raw and cooked tissue homogenates were used to determine the mechanisms of various iron forms on the catalysis of lipid peroxidation. Flax oil (0.25 g) was blended with 160 mL maleate buffer (0.1 M, pH 6.5) to prepare an oil emulsion. Raw or cooked turkey leg meat was used to prepare meat homogenates. Samples were prepared by adding iron from each of the various sources, reactive oxygen species, or enzyme (xanthine oxidase and superoxide dismutase) systems into the oil emulsion or meat homogenates. In oil emulsion and cooked-meat homogenates, ferrous iron and hemoglobin had strong prooxidant effects, but ferritin became prooxidant only when ascorbate was present. Hemoglobin and ferritin had no prooxidant effect in raw-meat homogenates. The status of heme iron and the released iron from hemoglobin had little effect on the prooxidant effect of hemoglobin in oil emulsion and cooked meat homogenate systems. The prooxidant effect of ferrous iron in oil emulsion and cooked-meat homogenates disappeared in the presence of superoxide (.O2-), H2O2, or xanthine oxidase systems. In raw-meat homogenates, however, ferrous had strong prooxidant effects even in the presence of .O2-, or H2O2. The status of free iron was the most important factor in the oxidation of oil emulsion and cooked-meat homogenates but the impact in raw-meat homogenates was small.  相似文献   
993.
Apoptosis or programmed cell death is the physiologic, natural form of cell death, exhibiting characteristic morphological and biochemical features. Apoptosis occurs upon developmental processes and represents an important defense mechanism. Defective apoptosis can result in a variety of diseases. Rapidly growing knowledge upon this mode of cell death, especially the identification of genes involved in the regulation of apoptosis raise the hope for new therapies in the treatment of cancer, autoimmune and neurodegenerative disorders, as well as viral infections.  相似文献   
994.
Increasing emphasis is now being placed on the assessment of patient outcomes, both in evaluating medical interventions and in quality assurance initiatives. Clinicians, purchasers, managers and researchers need outcome measures that are valid, reliable and responsive. This paper describes the theory and practice underlying the development of outcome measures for two chronic conditions, asthma and diabetes, for application in ambulatory settings. Existing generic and condition-specific health status and health-related quality-of-life measures were administered to almost 1300 patients. The psychometric properties of these measures were examined to identify those that were of adequate validity and reliability in these population groups. Step-wise regression procedures were then used to identify a core set of scales that best predicted patients' general health perceptions, which could be used in measuring general health outcomes for each of these groups. These core sets consist of up to 40 items, spanning physical function, energy and vitality, emotional well-being and condition-specific aspects of health such as symptom control. Further analysis is being carried out to assess the responsiveness to change of these core item sets.  相似文献   
995.
996.
Ten protein and enzyme polymorphic systems, viz. haemoglobin, albumin, transferrin, adenosine deaminase, adenylate kinase phosphoglucomutase, esterase-D, glyoxalase, alkaline phosphatase and amylase were studied in numigall (guinea fowl x chicken hybrids) to assess structural gene expression and regulatory gene divergence between the parental species. The investigation revealed presence of both the maternal and paternal electrophoretic components in case of adenosine deaminase, alkaline phosphatase, amylase, albumin and transferrin although no clear differences could be identified for haemoglobin and glyoxalase. Esterase-D and adenylate kinase phenotypes showed a dominance of the chicken type.  相似文献   
997.
It has been proposed that several nongenotoxic compounds act as hepatocarcinogens by suppressing the apoptosis that would normally act to remove damaged or potentially initiated cells from the liver. During our investigations of this hypothesis using a widely applied protocol, we have found that the stress induced by the process of gavage dosing can induce massive apoptosis in livers uniquely primed by withdrawal of the hepatomitogen cyproterone acetate from the hyperplastic rat liver. This effect of gavage dosing was not seen in livers of naive animals. Apoptosis was measured by both in situ end labeling (ISEL) of the DNA damage associated with programmed cell death and conventional hematoxylin and eosin (H&E) staining of apoptotic morphology. Apoptotic rates measured by H&E increased significantly from 0.005 +/- 0.010% on Day 11 to 0.657 +/- 0.315% of hepatocytes on Day 15, 4 days after cessation of 10 days dosing with CPA (120 mg/kg). The readministration of CPA suppressed > 89% of this Day 15 apoptosis. However, the readministration of vehicle alone (corn oil) caused a 390% increase in apoptosis to 2.56 +/- 1.31% of hepatocytes. Similar results were obtained using ISEL. Measurements of liver to body weight ratios and total DNA per liver reflected these changes in cell loss by apoptosis. In a second experiment, CPA was administered for 10 days as before then animals were subjected to readministration of CPA in corn oil, CPA in saline, corn oil, saline, or sham dosed. Again, apoptosis was dramatically suppressed by the readministration of CPA in either vehicle but was dramatically increased to around 2% of hepatocytes in all other groups, including the sham dosed group. Data on food consumption provided no evidence for a reduction in food intake as a causative agent but rather pointed to a less efficient usage of food in the stressed animals. The ability of stress to induce liver apoptosis should be borne in mind in the design and interpretation of future toxicological studies aimed at understanding the putative suppression of apoptosis by liver nongenotoxic carcinogens and other toxicants.  相似文献   
998.
The nucleotide sequences of the conjugative F plasmid transfer region genes, traV and traR, have been determined. The deduced amino acid sequence of TraV indicated that it may be a lipoprotein; this was confirmed by examining the effect of globomycin on traV-encoded polypeptides synthesized in minicells. An open reading frame that may represent a previously undetected transfer gene, now designated trbG, was identified immediately upstream of traV. The deduced product of traR was found to share amino acid similarity with proteins from the bacteriophages 186 and P2 and with the dosage-dependent dnaK suppressor DksA.  相似文献   
999.
The human neurotropic papovavirus JC, a close relative of simian virus 40, has been associated with the formation of brain tumors in humans because of its ability to induce such tumors in other primates under experimental conditions. Here we have analyzed 30 brain tumors classified as either oligodendroglioma or astrocytoma and 22 cell lines derived from human gliomas for the presence of JC viral sequences using polymerase chain reaction with two different sets of primers. None of the tumors or cell lines contained JC viral sequences. Similarly, we failed to detect expression of JC T antigen in any of 26 human glioma lines analyzed in this study. We conclude that JC virus is not a major cause of human brain tumors.  相似文献   
1000.
Japanese quail from lines that had been divergently selected for high (HL) or low (LL) plasma total cholesterol and their unselected control line (CL) were fed an all vegetable diet to which 0 or 0.5% crystalline cholesterol were added. Relationships between plasma and yolk cholesterol fractions were examined at 10, 14, and 18 wk of age, which followed 2, 6, and 10 wk consumption of the cholesterol-enriched diet, respectively. Unesterified cholesterol (UC) and cholesteryl esters (CE) in plasma and yolk were analyzed using HPLC. There were no consistent correlations between yolk and plasma for UC, individual CE, total esterified cholesterol (EC), or total cholesterol in the selected lines at ages tested, whether or not 0.5% cholesterol was added to the diet. Cholesterol concentrations in milligrams per gram of yolk and in milligrams per yolk were higher in the HL than the LL at 10 and 14, but not at 18 wk of age. Yolk weights of the HL females increased from 10 to 18 wk of age, whereas those of the LL did not. Cholesterol concentrations in the LL yolks continued to increase over time, however the increases in yolk weight in the HL were not accompanied by proportional increases in cholesterol deposition in the yolk, leading to a dilution of concentration of cholesterol fractions in the HL yolk. Dietary cholesterol increased egg production rate in the selected lines but did not increase the cholesterol content of the yolk.  相似文献   
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