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The smoking habits of 48 patients with malignant hypertension were compared with those of 92 consecutive patients with non-malignant hypertension. Thirty-three of the patients with malignant and 34 of the patients with non-malignant hypertension were smokers when first diagnosed. This difference was significant, and remained so when only men or black and white patients were considered separately. Results suggest that malignant hypertension is yet another disease related to cigarette smoking. 相似文献
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Hypertension is perceived to be an important problem among native people in Canada, but specific prevalence data have not been accumulated. A study was carried out to determine community levels of blood pressure and to document the prevalence of hypertension, obesity and cigarette smoking in nonurban Indians in three communities in northwestern Ontario. Of the 678 people present in the communities at the time of the survey 668 (98.5%) participated. Age- and sex-specific mean diastolic and systolic blood pressure readings are presented. The overall prevalence rate of hypertension was 13%; in 9.6% of those with hypertension the condition had previously been diagnosed. Blood pressure generally rose with increasing age, but diastolic pressure declined after age 50 in both sexes. The rate of obesity increased with increasing age; 70% of women aged 35 to 64 years and 50% of men aged 35 to 44 years were obese. Over half (56.4%) of the study population smoked, and most smokers were less than 35 years old. 相似文献
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Testing Heterozygote Excess and Deficiency 总被引:30,自引:2,他引:30
Currently used tests of Hardy-Weinberg proportions do not take into account the nature of the alternative hypothesis, which is generally a heterozygote deficiency. Different exact tests, appropriate for small sample size and large number of alleles, are proposed in this perspective, and their properties are evaluated by power comparisons. Some tests are found to be close to optimal for the detection of inbreeding or heterozygote excess, one of which is a score test closely related to Robertson and Hill's estimator of the inbreeding coefficient. This test is also easily applied to multiple samples. Such tests are not always the most appropriate if alternative hypotheses differ from those considered here. 相似文献
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R G Rawbone 《BMJ (Clinical research ed.)》1980,281(6235):309-310
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Observations on "excess mortality" from influenza, carried out in the Moldavia area between 1957 and 1973, are presented in the paper. They made it possible to assess in time and space as well as in severity the knowledge on influenza epidemics. "Excess mortality" proved to be a valuable indicator of increase in influenza mortality, especially, on the occurrence of big epidemics the existence of which was closely related to the appearance of new types and variants of influenza viruses. Though "excess mortality" showed the highest values when death from acute pneumopathies recorded in the preepidemic and postepidemic periods was included in the calculation, it also pointed to the strong effect of influenza on all causes of death, especially chronic diseases of the respiratory and cardio-vascular systems. 相似文献
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Excess dietary methionine and pregnancy in the rat 总被引:1,自引:0,他引:1
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In a simulated hydrothermal environment allowing fluid circulation between hot and cold regions repeatedly, D- and L-alanine molecules were racemized differently depending upon the concentration of alanine, whether D or L, present in the solution. In particular, the relative population of L-alanine was slightly more enhanced compared to that of D-alanine when the concentration of alanine increased. Enantiomeric excess of L-alanine was also observed when metallic ions such as zinc were sufficiently present in the environments. Hydrothermal environments in the primitive ocean could have maintained the capacity of selectively retaining enantiomeric excess in favor of L-amino acids once the concentration of amino acids could reach a sufficiently high level. 相似文献
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The effect of excess macronutrients in the root environment on mannitol and sucrose metabolism was investigated in celery (Apium graveolens L. var dulce [Mill.] Pers.). Plant growth was inhibited progressively as macronutrient concentration in the media, as measured by electrical conductivity (E.C.), increased from 1.0 to 11.9 decisiemens m-1. Plants grown for 35 d at higher E.C. had a lower water content but similar dry weight in their roots, leaves, and petioles compared to plants grown at lower E.C. Macronutrient concentrations of leaves, roots, and petioles were not affected by the imposed stress, indicating that the macronutrient stress resulted in a water-deficit stress response rather than a salt-specific response. Mannitol accumulated in sink tissues and was accompanied by a drastic decrease in activity of mannitol-1-oxidoreductase. Sucrose concentration and activities of sucrose-metabolizing enzymes in sink tissues were not affected by the macronutrient stress. Mature leaves exhibited increased concentrations of both mannitol and sucrose, together with increased activity of mannose-6-phosphate reductase and sucrose phosphate synthase, in response to macronutrient stress. Thus, mannitol accumulation in osmotically stressed celery is regulated by diminished catabolism in sink tissues and increased capacity for mannitol biosynthesis in source leaves. 相似文献
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The proportion of spermatozoa with elongated nuclei in ejaculates from a strain of guinea fowl was estimated, subjectively, to range from approximately 1 to 6%. It was confirmed by image analysis that in an ejaculate from one male, the distribution of nuclear lengths was bimodal, with a distinct population comprising 10% of spermatozoa having a mean nuclear length that was 52% greater than that of the remaining 90%. Furthermore, the mean DNA content of the 'large-nuclei' population was 1.85 times (not significantly different from twice) that of the main sperm population. The proportion of large-nuclei spermatozoa that was motile was less than that of normal sperm (31% versus 59%) and the velocity of motile spermatozoa was also less (24 microm/s versus 72 microm/s). The poor motility of the large-nuclei spermatozoa in vitro was reflected in their limited performance in vivo, since only 1.1% were found associated with the egg outer perivitelline layer. This is the first report to quantify the occurrence of, presumed, polyploid spermatozoa in a domestic bird. The incidence of such spermatozoa in commercial guinea fowl and other domestic poultry and the genesis and effects on fertility of such spermatozoa may be significant. 相似文献
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Excess weight and sleep-disordered breathing. 总被引:2,自引:0,他引:2
Excess weight is a well-established predictor of sleep-disordered breathing (SDB). Clinical observations and population studies throughout the United States, Europe, Asia, and Australia have consistently shown a graded increase in the prevalence of SDB as body mass index, neck girth, or other measures of body habitus increases. Clinical studies of weight loss and longitudinal population studies provide strong support for a causal association. The role of excess body weight, a modifiable risk factor, with SDB raises many questions relevant to clinical practice and public health. The topic takes on added importance with the alarming rate of weight gain in children as well as adults in industrialized nations. Among adults ages 30-69 yr, averaging over the estimated United States 2003 age, sex, and BMI distributions, we estimate that approximately 17% of adults have mild or worse SDB (apnea-hypopnea index > or = 5) and that 41% of those adults have SDB "attributable" to having a body mass index of > or =25 kg/m(2). Similarly, we estimate that approximately 5.7% of adults have moderate or worse SDB (apnea-hypopnea index > or = 15) and that 58% of those adults have SDB attributable to excess weight. Clearly, if the expanding epidemic of obesity seen in the United States continues, the prevalence of SDB will almost certainly increase, along with the proportion of SDB attributable to obesity. 相似文献
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The radioactivities of mixtures of trypsin and HB3O3 or LiCl have been measured and compared with the radioactivity of the constituents. No evidence was found for the production of heavy particles, as had been previously reported, neither were the excess counting rates of the mixtures over that of its constituents as large. The residual excess radioactivity was about four orders of magnitude smaller than that published, yet was still statistically significant, consisting mainly of electrons having a maximum energy less than about 400 keV. The excess radioactivity of a mixture of trypsin and LiCl had a probable half-life between 5 and 46 days. Possible mechanisms for these excesses are discussed. 相似文献
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Kun Zhang Yihao Zhu Xiaoyu Wang Xin Zhao Shu Li Xiaohua Teng 《Biological trace element research》2017,177(2):297-315
Methyl mercury (MeHg) is a developmental neurotoxin that causes irreversible cognitive damage in offspring of gestationally exposed mothers. Currently, no preventive drugs are established against MeHg developmental neurotoxicity. The neuroprotective effect of gestational administration of a flavanoid against in utero toxicity of MeHg is not explored much. Hence, the present study validated the effect of a bioactive flavanoid, fisetin, on MeHg developmental neurotoxicity outcomes in rat offspring at postnatal weaning age. Pregnant Wistar rats were simultaneously given MeHg (1.5 mg/kg b.w.) and two doses of fisetin (10 and 50 mg/kg b.w. in two separate groups) orally from gestational day (GD) 5 till parturition. Accordingly, after parturition, on postnatal day (PND) 24, weaning F1 generation rats were studied for motor and cognitive behavioural changes. Biochemical and histopathological changes were also studied in the cerebral cortex, cerebellum and hippocampus on PND 25. Administration of fisetin during pregnancy prevented behavioural impairment due to transplacental MeHg exposure in weaning rats. Fisetin decreased the levels of oxidative stress markers, increased enzymatic and non-enzymatic antioxidant levels and increased the activity of membrane-bound ATPases and cholinergic function in F1 generation rats. In light microscopic studies, fisetin treatment protected the specific offspring brain regions from significant morphological aberrations. Between the two doses of fisetin studied, 10 mg/kg b.w. was found to be more satisfactory and effective than 50 mg/kg b.w. The present study shows that intake of fisetin during pregnancy in rats ameliorated in utero MeHg exposure-induced neurotoxicity outcomes in postnatal weaning F1 generation rats. 相似文献