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MASAYA YAGO TAKASHI YOKOCHI MARIKO KONDO MICHAEL F. BRABY BAKHTIAR YAHYA DJUNIJANTI PEGGIE MIN WANG MARK WILLIAMS SADAYUKI MORITA REI UESHIMA 《Zoological Journal of the Linnean Society》2012,164(2):304-327
Adults of the Euthalia phemius complex, which is composed of three South‐East Asian nymphalid species, Euthalia phemius, Euthalia ipona, and Euthalia euphemia, were genetically analysed by examining mitochondrial and nuclear genes. The E. phemius complex was also examined morphologically, with particular emphasis on wing markings and male genitalia. No significant differences amongst the three species in the complex were detected with respect to either genetic distance or genital morphology. We therefore conclude that the three currently recognized Euthalia species belong to a single species. Accordingly, E. ipona is synonymized with E. phemius. Euthalia euphemia is treated as a subspecies of E. phemius. Type specimens of all taxa and a synonymic list for the E. phemius complex are also given. In addition, we briefly discuss the evolution and biogeography of the species complex. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 164 , 304–327. 相似文献
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SEAN J. BLAMIRES CHUN‐LIN WU TODD A. BLACKLEDGE I‐MIN TSO 《Biological journal of the Linnean Society. Linnean Society of London》2012,106(3):580-588
Many spiders use silk to construct webs that must function for days at a time, whereas many other species renew their webs daily. The mechanical properties of spider silk can change after spinning under environmental stress, which could influence web function. We hypothesize that spiders spinning longer‐lasting webs produce silks composed of proteins that are more resistant to environmental stresses. The major ampullate (MA) silks of orb web spiders are principally composed of a combination of two proteins (spidroins) called MaSp1 and MaSp2. We expected spider MA silks dominated by MaSp1 to have the greatest resistance to post‐spin property change because they have high concentrations of stable crystalline β‐sheets. Some orb web spiders that spin three‐dimensional orb webs, such as Cyrtophora, have MA silks that are predominantly composed of MaSp1. Hence, we expected that the construction of three‐dimensional orb webs might also coincide with MA silk resistance to post‐spin property change. Alternatively, the degree of post‐spin mechanical property changes in different spider silks may be explained by factors within the spider's ecosystem, such as exposure to solar radiation. We exposed the MA silks of ten spider species from five genera (Nephila, Cyclosa, Leucauge, Cyrtophora, and Argiope) to ecologically high temperatures and low humidity for 4 weeks, and compared the mechanical properties of these silks with unexposed silks. Using species pairs enabled us to assess the influence of web dimensionality and MaSp composition both with and without phylogenetic influences being accounted for. We found neither the MaSp composition nor the three‐dimensionality of the orb web to be associated with the degree of post‐spin mechanical property changes in MA silk. The MA silks in Leucauge spp. are dominated by MaSp2, which we found to have the least resistance to post‐spin property change. The MA silk in Argiope spp. is also dominated by MaSp2, but has high resistance to post‐spin property change. The ancestry of Argiope is unresolved, but it is largely a tropical genus inhabiting hot, open regions that present similar stressors to silk as those of our experiment. Ecological factors thus appear to influence the vulnerability of orb web spider MA silks to post‐spin property change. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 106 , 580–588. 相似文献
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利用内蒙古锡林浩特国家气候观象台1994~2009年牧草生长季逐月实测资料,对CENTURY模型进行检验,模拟内蒙古典型草原1953~2010年间地上净初级生产力(ANPP)动态,并与26个气象因子进行相关性分析。模型检验结果显示,模拟值与观测值之间的相关系数为R2=0.66,斜率b=0.95,误差平方根值为50.51 g·m-2,平均绝对百分比误差为44.19%。结果表明:(1)CENTURY模型能比较准确地模拟这类草原的季节动态和年际变化;在过去的58年中,内蒙古典型草原温度增加,降水减少,ANPP下降;ANPP变化趋势与降水量相似。(2)用实际气象观测资料模拟获得的ANPP随气温和降水的变化呈现出明显的变化规律,生长季内地上生物量对降水和温度的季节性分布也非常敏感;相关分析进一步表明,ANPP对生长季内降水量和极端高温非常敏感,而与年极端最低气温、平均地面温度、日照时数、平均风速和最大积雪深度无显著相关关系;过去58年研究区ANPP下降是降水减少、温度升高以及干旱事件频发共同作用的结果。(3)根据预测,在SRES B2情景下,未来50~100年内蒙古典型草原生长季平均最高气温和最低气温都将呈升高趋势,2080s分别升高4.01℃、4.35℃,每10年增加速率分别为0.35℃和0.38℃;降水量略呈增加,2020s、2050s和2080s研究区生长季将分别增加3.17%、5.13%和7.03%,每10年增加速率为0.09 mm;ANPP呈下降趋势年际间波动较大,2020s、2050s和2080s研究区将分别下降5.76%、7.52%和11.42%,每10年下降速率为0.76 g·m-2。 相似文献
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冯婉娟徐子静孟令锋张蓉颖 《现代生物医学进展》2012,12(13):2582-2584
细胞内各个细胞器之间通过囊泡的膜转运是真核细胞存在的基本。Rab蛋白确保了转运蛋白被运输至正确的目的地。Rab蛋白是小GTP酶中的一大家族,它通过募集其效应物蛋白,其中包括接头蛋白,栓系因子,激酶,磷酸酶以及动力蛋白等,调控了细胞膜的选取,囊泡出芽,去包被,转运以及膜融合等过程。本文主要从Rab蛋白循环着手,依次论述了Rab蛋白在囊泡出芽,去包被,转运和膜融合等过程中起到的作用,从而使读者对Rab蛋白能有一个更加系统的了解。 相似文献
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Survivin是近年来发现的一种凋亡抑制因子,属于凋亡抑制蛋白(inhibitor of apoptosis proteins,IAP)家族的新成员;主要通过抑制caspase-3和caspase-7的活性而阻断细胞凋亡过程. Survivin选择性地表达于胚胎发育组织和大多数肿瘤组织,而正常成人终末分化组织中不表达. Survivin参与了细胞周期调控,与肿瘤的发生、发展和预后密切相关,可作为肿瘤治疗的新靶点. 相似文献
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Human fibrinogen-related protein-1/liver fibrinogen-related protein-1 (HFREP-1/LFIRE-1), a liver-specificprotein, is a member of fibrinogen superfamily that exerts various biological activities. However, the func-tion of HFREP-1/LFIRE-1 in liver remains unknown. Here we isolated its mouse ortholog gene-mousefibrinogen-related protein-1 (mfrep-1), which encoded 314 amino acids, exhibiting 80.4% similarity toHFREP-1/LFIRE-1. Northern blot analysis revealed that 1.2-kb mfrep-1 mRNA was detected selectivelyin mouse liver. To explore the function of MFREP-1, we examined the levels of mfrep-1 mRNA duringregeneration after 70% partial hepatectomy (PHx) in mice. mfrep-1 mRNA increased in the regeneratingliver and reached the first shoulder peak at 2-4 h after PHx. Cycloheximide pretreatment could suppress theinduction of mfrep-1, indicating the up-regulation of this gene need de novo protein synthesis. Its mRNAcontinued to elevate at 6 h thereafter and reached the second peak at 24 h. The enhanced expression ofmfrep-1 maintained high until 72 h and then declined slowly to the basal level. Immunohistochemistryassessment confirmed the up-regulated expression of MFREP-1 protein in parenchymal cells during liverregeneration. These data suggested that MFREP-1 might play an important role in liver regeneration andbe involved in the regulation of cell growth. 相似文献