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排序方式: 共有72条查询结果,搜索用时 203 毫秒
11.
S Lindeberg E Berntorp P Nilsson-Ehle A Terént B Vessby 《Canadian Metallurgical Quarterly》1997,66(4):845-852
This study examined cross-sectional age relations of blood pressure, anthropometric indexes, serum lipids, and hemostatic variables in 203 subsistence horticulturists aged 20-86 y in Kitava, Trobriand Islands, Papua New Guinea. The population is characterized by extreme leanness (despite food abundance), low blood pressure, low plasma plasminogen activator inhibitor 1 activity, and rarity of cardiovascular disease. Tubers, fruit, fish, and coconut are dietary staples whereas dairy products, refined fat and sugar, cereals, and alcohol are absent and salt intake is low. Although diastolic blood pressure was not associated with age in Kitavans, systolic blood pressure increased linearly after 50 y of age in both sexes. Body mass index decreased with age in both sexes. Serum total cholesterol, triacylglycerol, low-density-lipoprotein cholesterol, and apolipoprotein B increased in males between 20 and 50 y of age, whereas high-density-lipoprotein cholesterol and apolipoprotein A-I decreased. There were no significant differences in these indexes with age in the few females studied. A slight linear age-related increase of lipoprotein(a) was present in males. Plasma fibrinogen, factor VII clotting activity, factor VIII clotting activity, and von Willebrand factor antigen increased with age in both sexes but plasminogen activator inhibitor 1 activity did not. The modest or absent relations between the indexes measured and age are apparently important explanations of the virtual nonexistence of stroke and ischemic heart disease in Kitava. 相似文献
12.
In this study we analysed the changes in the properties of rat cerebral cortex Na+K(+)-ATPase in streptozotocin induced diabetes (STZ-diabetes). Special attempt was made to determine whether insulin treatment of diabetic animals could restore the altered parameters of this enzyme. Na+/K(+)-ATPase activity was found to be decreased by 15% after 2 weeks, and by 37% after 4 weeks in diabetic rat brains with a parallel decrease in maximal capacity of low affinity ouabain binding sites. There was no significant change in the high affinity ouabain binding sites. The Kd values did not change significantly. Western blot analysis of brain Na+/K(+)-ATPase isoforms indicated a 61 +/- 5.8% and 20 +/- 2.8% decrease of the alpha 1 and alpha 3 isoforms, respectively in 4 weeks diabetic animals. Change in the amount of the alpha 2 isoform proved to be less characteristic. Both types of beta subunit isoform showed a significant decrease in four weeks diabetic rats. Our data indicate a good correlation in diabetic rats between changes in Na-/K(+)-ATPase activity, low affinity ouabain binding capacity and the level of alpha 1 isoform. While insulin treatment of diabetic animals restored the blood glucose level to normal, a complete reversal of diabetes induced changes in Na+/K(+)-ATPase activity, ouabain binding capacity and Na+/K(+)-ATPase isoform composition could not be achieved. 相似文献
13.
Hausmann Markus; Slabbekoorn Ditte; Van Goozen Stephanie H. M.; Cohen-Kettenis Peggy T.; Güntürkün Onur 《Canadian Metallurgical Quarterly》2000,114(6):1245
The aim of this study was (a) to show that different measures of spatial cognition are modulated by the menstrual cycle and (b) to analyze which steroid is responsible for these cognitive alterations. The authors collected blood samples in 3-day intervals over 6 weeks from 12 young women with a regular menstrual cycle to analyze concentrations of estradiol, progesterone, testosterone, luteinizing hormone, and follicle-stimulating hormone. The performance on 3 spatial tests was measured during the menstrual and the midluteal phases. A significant cycle difference in spatial ability as tested by the Mental Rotation Test was found, with high scores during the menstrual phase and low scores during the midluteal phase. Testosterone had a strong and positive influence on mental rotation performance, whereas estradiol had a negative one. These results clearly indicate that testosterone and estradiol are able to modulate spatial cognition during the menstrual cycle. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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A dry, batch anaerobic digestion (DBAD) process was tested on two sewage sludge types with different methanogenic seed fractions under laboratory conditions. The aim was to indicate optimal sludge:seed mixing ratios and analyse process performance based on degradation rate and reactor-specific methane production. The attained results were compared with the performance of a liquid-state, laboratory-scale stirred reactor (SR). A mixing ratio of at least 1:1.25 (sludge:seed) yielded processes free from significant inhibitions. Further seeding increments resulted in slightly better performances, but much lower sludge fractions treated in the reactors. Compared with the SR process, the DBAD reactors produced comparable degradation rates albeit in a significantly longer process and with somewhat lower reactor-specific methane production rates. These findings indicate that the DBAD method may provide a viable alternative to liquid-state processes if sludge drying is already applied and reactor volume requirements are of importance. 相似文献
17.
离子色谱在乙二醛电氧化过程中的应用 总被引:4,自引:0,他引:4
基于离子色谱原理,成功地研发出一种适用于乙二醛电氧化过程主要物种快速检测的新技术。研究表明,该技术不仅具有设备简便,检测快速灵敏和选择性高等优势,而且还能实现同时测定多种组分的目的。检测灵敏度小于0 5mg/L,保留时间、峰高、峰面积的变异系数均小于2%;对各物种回收率的检测结果为97%~103%。离子色谱电导检测技术的成功研发为乙二醛电氧化过程物种的实时、快速检测提供了便捷的分析手段,这对电合成体系的生产指导和过程评价具有重要意义。 相似文献
18.
Le Coënt Adrien Alexandre dit Sandretto Julien Chapoutot Alexandre 《Software and Systems Modeling》2021,20(3):711-724
Software and Systems Modeling - In this paper, we tackle the problem of guaranteed simulation of cyber-physical systems, an important model for current engineering systems. Their is always... 相似文献
19.
F Szántó 《Canadian Metallurgical Quarterly》1998,139(44):2639-2642
The author reports on the up to date view of the hormone replacement therapy of women with postmenopausal complaints. The benefits of the hormone replacement therapy in the treatment of vasomotor symptoms and bleeding disorders and in the prevention of cardiovascular disease and postmenopausal osteoporosis are discussed. The connection between hormone replacement therapy, thromboembolism and cancer are reported. In the authors opinion, the hormone replacement therapy must be available for all the most women suffering from climacteric complaints. A strong cooperation between the menopausal care units and GP-s is advisable. 相似文献
20.
We reviewed microbiology and infection control records at a Memphis children's hospital from 1982 to 1990 to obtain epidemiologic, clinical, and microbiologic data on group A streptococcal (GAS) bacteremia. Varicella was the underlying condition in 8 of 37 (22%) patients identified and was often associated with severe GAS disease, including toxic shock-like syndrome. Twenty-one of 31 (68%) available blood isolates made GAS pyrogenic exotoxin (SPE) B by Ouchterlony immunodiffusion; gene probes identified speC and speA in 18 (58%) and 8 (26%) isolates, respectively. The B/C toxin profile, identified in 11 (35%) isolates, was the most common profile in this population, and the overall rate for speC was higher than rates recently reported from other areas. Although the clinical significance of the toxin profiles in our population is unclear, these data emphasize the geographic and temporal variability in the microbiologic properties of GAS disease. 相似文献