994 resultados para 42-378
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Planktobenthos was sampled in 1957-58 in the river Amur. A determination of the kind of organisms drifting in the mass of water of the Amur was carried out. Of special interest for the authors was the activity of drifting of benthic larvae.
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Despite the fact that it is a long time sinc e the methods of collection and quantitative estimatio n of protozoa were worked out data on the abundance of these animals in freshwaters are not very numerous. Nevertheless, Infusoria and Rhizopoda at high densities are widespread in the water and sediments of lakes and reservoirs. In order to find ou t the importance of infusoria as a food source for cyclopoids we carried out experimental investigations using C14. For this three species of cyclopoids, widely distributed in open regions of Rybinsk reservoir were selected: Cyclops vicinus, Mesocyclops oithonoides and Kesocyclops leuckarti. The data presented give evidence that the species investigated are able as predators to consume infusorian plankton arid bacteria in the form of flocs or small clumps of detritus.
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Drawing of Charles Darwin made in 1840 by George Richmond. Contents.
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Charles Darwin Foundation for the Galapagos Islands.
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The output spectrum of Yb-doped double-clad fiber superfluorescent source (SFS) is tailored by placing a broadband dichroic mirror in the pump end of conventional single-pass forward configuration, which constitutes double-pass forward configuration. The 3 dB bandwidth is increased from I I to 42 nm. A maximum output SFS power of 2.12 W and a slope efficiency of 43.2% are obtained. The double-clad fiber is 25 in and the pump power is adequate to saturate the fiber as far as the feedback-induced lasing appears. (c) 2004 Elsevier Ltd. All rights reserved.
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mtDNA genotypes of six domestic horses (three adult short horses whose heights are under 1 m and three common domestic horses) from a small region of 15 km(2) in Malipo county of Yunnan province of China were investigated by the technique of restriction fragment length polymorphism (RFLP) with restriction endonucleases which recognize 6-bp sequences. An average of fragments for an individual was obtained. Unlike other domestic animals, this population of horses exhibits high mtDNA genetic diversity. Each of the six horses has a specific mtDNA genotype showing a pattern of multiple maternal origins, as suggested by fossil and literature records. We think the population of horses is an amazing seed-resource pool of horses and hence deserves to be paid more attention from the view of conservation genetics. However it is also remarkable that we did not find any typical mtDNA genetic markers which would discriminate between short horses and common domestic horses.
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本发明涉及一种大蹼铃蟾博玛津蛋白及其基因和在制药中的应用,属于生物医学领域。大蹼铃蟾博玛津蛋白是从中国两栖类动物大蹼铃蟾皮肤分泌物中分离得到的一种单链多肽,氨基酸全序列为:NH2GFPIYEIDNRPGCYVDPAERVACAGAGVTKAECKAKGCCFISARRNTIWCFKLKESADAWKCAVPMNTRVACAGAGVTPAECKGKGCCFSSYYGTV WCFKPQE-COOH)编码大蹼铃蟾博玛津蛋白的基因的cDNA由1061个核苷酸组成,编码成熟血小板活化蛋白为第67-378位核苷酸。博玛津具有诱导血小板活化、抑制胃溃疡的作用,可作为血小板聚集诱导剂和制备胃溃疡药物的应用。
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The 4-bp deletion (-CTTT) at codon 41/42 (CD41/42) of the human beta-globin gene represents one of the most common beta-thalassemia mutations in East Asia and Southeast Asia, which is historically afflicted with endemic malaria, thus hypothetically evolvi
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本发明涉及一个脱毛相关基因及其应用,属于生物技术领域。本发明确定了一无毛基因与昆明小鼠脱毛性状的相关性。该基因被定位于小鼠14号染色体,在细胞遗传图谱上的位置是14D1,在连锁图谱上的位置是39.5cM,全长约20.281KbDNA序列,转录产物(cDNA)有4017bp,含有19个外显子,从成熟mRNA的第378位(2号外显子)开始翻译,共编码1182个氨基酸残基。通过测序,该基因第2817位无义突变(C→T)是导致昆明种犀牛小鼠KIZ脱毛的遗传基础。而且,该基因在人类基因组中也非常保守,具有相似的功能。所以该基因可以用来研究人秃头症的致病机理,以及作为设计治疗丘疹性秃头症药物的靶基因。
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青年牛(12月龄)和经产牛(7-8岁)平均卵泡数(≥2mm)及>10mm卵泡数明显高于老年牛(≥14岁)(P<0.01)。青年牛和经产牛平均卵母细胞数及平均COC数高于老年牛(P<0.05)。1和2级卵母细胞比例青年牛高于或等于经产牛高于老年牛,3和4级卵母细胞比例老年牛高于经产牛高于或等于青年牛(P<0.05)。青年牛和经产牛2级卵母细胞占优势,而老年牛3级卵母细胞居多。不同剂量外源性FSH诱导后,经产牛和老年牛平均卵泡数在各剂量组之间没有显著差异(P>0.05);但≥6mm卵泡数及2级卵母细胞比例明显增加,而2-5mm卵泡数相应减少及裸卵和老化卵比例降低(P<0.05)。在10次取卵过程中,青年牛和经产牛发情当天平均卵母细胞数均较以后各次的数量低(P<0.05)。