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The interaction between age at menopause and postmenopausal body composition development was tested with in 178 Viennese women aged 47 to 68 years (x=55.4 yr). Postmenopausal body composition was described using dual energy x-ray absorptiometry by absolute fat and lean mass and bone mineral content of the whole body, the arms, legs, the trunk and the head. Upper and lower amount of body fat, the fat percentages of the individual body compartments and the fat distribution index were calculated. Postmenopausal body fat and lean soft tissue mass and postmenopausal bone mineral content were significantly associated with the age at menopause. Women whose menopause occurred late showed the highest amount of body fat (31.2+/−7.7kg) and lean body mass (41.2+/−4.4 kg) postmenopausally, while women with an early menopause exhibited the lowest amount of body fat (27.5+/−8.9kg) and lean body mass (38.4+/−5.4 kg) during the postreproductive phase of life (p<0.05). Women whose menopause occurred later than 51 had a significant higher postmenopausal bone mass (2.26+/−0.9kg versus 2.09+/−0.3 kg; p<0.05). A late menopause was associated with a significantly higher value in fat mass, lean body mass and in bone mineral content. Therefore age at menopause may be assumed as an indicator for body fat and bone mineral content during postmenopause and postmenopausal fat distribution patterns.  相似文献   

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The biological basis underlying the increased risk of nondisjunction in offspring of women of advanced maternal age is not understood. We sought to test the hypothesis that maternal reproductive age (distance in time from approaching menopause) rather than chronological age is pivotal in the etiology of nondisjunction. Our results found no difference in age of menopause between women 30 years old at delivery of a child with trisomy 21 (i.e., age-related nondisjunction) compared to controls. Among women <30 years of age at delivery of a child with trisomy 21, none underwent premature menopause. Therefore, our findings fail to support the theory that reproductive age plays a major role in the etiology of nondisjunction.  相似文献   

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When an autophagosome or an amphisome fuse with a lysosome, the resulting compartment is referred to as an autolysosome. Some people writing papers on the topic of autophagy use the terms “autolysosome” and “autophagolysosome” interchangeably. We contend that these words should be used to denote 2 different compartments, and that it is worthwhile maintaining this distinction—the autophagolysosome has a particular origin in the process of xenophagy that makes it distinct from an autolysosome.  相似文献   

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《Autophagy》2013,9(4):549-551
When an autophagosome or an amphisome fuse with a lysosome, the resulting compartment is referred to as an autolysosome. Some people writing papers on the topic of autophagy use the terms “autolysosome” and “autophagolysosome” interchangeably. We contend that these words should be used to denote 2 different compartments, and that it is worthwhile maintaining this distinction—the autophagolysosome has a particular origin in the process of xenophagy that makes it distinct from an autolysosome.  相似文献   

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The objective of the present study was to investigate physiological effects of a marginal copper and iron supply on pigs. Therefore an experiment was conducted with 4 × 12 growing pigs of the crossbreed Pietrain × Deutsche Landrasse. The animals were fed for a period of 119 days with a diet poor of copper (1.5 mg Cu/kg diet) and/or poor of iron (35 mg Fe/kg diet). Control animals were supplied adequately with copper (4.8 mg Cu/kg diet) and iron (85 mg Fe/kg diet). The diet was given according to weight. After reaching an average weight of 102.6 ± 3.5 kg the animals were slaughtered. Due to the activity of the coerulplasmin and katalase enzyme and the haematological parameters, the supply of copper and iron could be classified as marginal. There was no interaction between copper deficiency and iron metabolism. The protein metabolism was unchanged. Low copper intake reduced the copper concentrations in serum, liver, muscle and backfat, and low iron intake reduced the iron concentration in serum, liver and muscle. Marginal copper and iron supply had no relevant effect on either food intake and growth performance or carcass characteristics and meat quality.  相似文献   

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Beyond the energy requirement of maintenance, the assimilated energy, occurring in bioproducts, is linearly proportional to the intake of metabolizable energy in non‐underfed conditions. In contrast, resting metabolic rate is differing between individuals within a population of an animal species. As adaptability to changed environmental conditions may play a role, young bulls were exposed to thermoneutral (18°C) and low (4°C) ambient temperatures and were fed at two feeding levels (1.0 and 1.6 times energy requirement in maintenance) to produce metabolic rate differences, using the same animals, metabolic rate was altered by reducing the sympathetic outflow in each case. Expression of sulfonylurea receptors in circulating mononuclear leukocytes and cells from skeletal muscle (m. semitendinosus) was studied by flow cytom‐etry. Changes of metabolic rate at rest corresponded to the portion of cells with sulfonylurea receptors expression. The data from reducing the sympathetic outflow and those from sulfonylurea receptors expression are useful to explain metabolic rate differences among individuals of an animal population.  相似文献   

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Many health effects can be attributed to the Mediterranean herb oregano (Origanum vulgare L.) and several studies demonstrated the improving effect on performance, changes in blood count, antibacterial, antifungal and immunmodulating abilities. The majority of these investigations were carried out with processed essential oil, while whole plant material was only used in a few studies. Thus, the aim of the present experiment was to test the effect of increasing proportions of dried oregano in piglet feed on health and performance, with a special focus on immune modulation. A total of 80 male castrated weaned piglets (body weight [BW] 7.9 kg ±1.0 kg) were used in a feeding experiment lasting 5 weeks. They were assigned to 4 experimental groups: a control diet, and three diets with an oregano supplementation at 2 g, 4 g and 8 g per kg feed, respectively, corresponding to 23.5 mg, 46.9 mg and 93.9 mg carvacrol/kg DM. After 3 weeks, half of each group was challenged with 5 µg lipopolysaccharides (LPS) per kg BW. Blood samples were collected 2 h after LPS stimulation and analysed for T-cell phenotypes, granulocyte activity, clinical-chemistry as well as white and red blood count. The results indicate no effects of oregano on performance. In contrast, oregano altered the lymphocyte proportion and the ratio of CD4+ and CD8+ T-cells as well as the triglyceride concentration in the serum of non-stimulated and in LPS-stimulated piglets. In conclusion, whole plant supplementation of oregano to piglet feed altered immune-related parameters, but did not modulate the acute inflammatory response induced by LPS stimulation.  相似文献   

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Stereocontrol in bakers' yeast reduction can be achieved by introduction of a sulfur functional group into substrates. α-Methylthio-β-keto esters are reduced to give exclusively (3S)-3-hydroxy esters. α-Substituted β-keto thiol esters and dithioesters afford (2R,3S)-3-hydroxy esters with high diastereo-and enantioselectivity. Ketones possessing 1,3-dithiane, phenylsulfenyl, or phenylsulfonyl groups at the α-position are transformed also into the corresponding (S)-secondary alcohols. Optically pure (S)-(phenylsulfinyl)acetones can be obtained by kinetic resolution of racemic derivatives with the yeast. Diastereo- and enantioselective reduction of 1,2-diketones leading into (1S,2S)-1,2-diol derivatives can be also achieved by introduction of 1,3-dithiane, phenylsulfenyl or phenylsulfonyl groups into the α-position. Reductions of carbon-carbon double bond of sulfur-functionalized prenyl derivatives provide both chiral (R)- and (S)-C5-building blocks for terpenoid synthesis. The utility of the reduction products as chiral building blocks is demonstrated in the synthesis of biologically active natural products such as pheromones, sugars, antibiotics etc. by functional group transformation and carbon-carbon bond formation reactions with the aid of sulfur functional groups.  相似文献   

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人口、食物、资源、环境与生物学钱燕文(中国科学院动物研究所北京100080)人家都说下一个世纪是生物学的世纪,人口、食物、资源、环境也是近20年来的热门话题,因为这四个方面关系到我们人类的未来。为什么下个世纪是生物学的世纪?也得从人口、食物、资源、环...  相似文献   

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Barley, probably the oldest cultivated cereal, is widely grown in cooler areas of the world. The annual world production of nearly two and a half billion bushels exceeds that of rye but is less than that of rice, wheat, corn and oats, respectively. Most of the annual 300 million dollar crop of the U.S. is fed to livestock, but about one- third is manufactured into malt.  相似文献   

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Liu YX 《生理科学进展》2005,36(2):97-101
刘以训教授是我国著名的生物学家,中国科学院院士。他致力于生殖生物学研究,在排卵、黄体萎缩、精子发生和胚胎植入等系列研究上,成绩卓著,享有国际声誉。读罢此文,钦敬之情油然而生。  相似文献   

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