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991.
Lysosomal heterogeneity between and within cells with respect to resistance against oxidative stress 总被引:5,自引:0,他引:5
The prevailing opinion on lysosomal endurance is that, as long as the cells are still alive, these organelles are generally
quite stable and, thus, do not induce cell damage by leaking their numerous powerful hydrolytic enzymes to the cytosol. We
suggest that this opinion is basically wrong and consider that many lysosomes are quite vulnerable, especially to oxidative
stress. Moreover, we suggest that cellular degeneration, including apoptosis as well as necrosis, follows upon lysosomal disruption.
We have found differing stability of lysosomal membranes to oxidative stress, not only among different cell types, but also
between cells of the same type and between lysosomes of individual cells. We suggest that cellular resistance to oxidative
stress is mainly a function of three parameters: (i) the capacity to degrade hydrogen peroxide before it reaches, and may
diffuse into, the acidic vacuolar compartment; (ii) the resistance to reactive oxygen species of lysosomal membranes; and
(iii) the intralysosomal amounts of redox-active, low molecular weight iron. Iron-catalysed intralysosomal reactions, if pronounced
enough, result in peroxidation and destabilization of the lysosomal membrane. Owing to differences in the cellular synthesis
of hydrogen peroxide-degrading enzymes, degree of autophagocytotic degradation of iron-containing metalloproteins, lysosomal
localization within the cytoplasm and intralysosomal iron chelation, the above three parameters may vary between both different
and similar cells and between lysosomes of individual cells as well, explaining their observed variability with respect to
resistance against oxidative stress
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
992.
Maria Keramida John M. Matsoukas Dimitris Panagiotopoulos Kostas Alexopoulos Elizabeth Matsoukas John Cladas Vasilis A. Tzingounis Emmanuel Cardamakis Hernâni L. S. Maia Debanaba Pati Hamid R. Habibi 《Letters in Peptide Science》1996,3(4):257-262
Summary Gonadotropin-releasing hormone (GnRH) stimulates the release and synthesis of gonadotropin hormones (GtH) and is the key regulator of reproduction. The present study was carried out to design a potent GnRH analogue containing Tyr(OMe) at position 5 and ad-amino acid at position 6. This was based on a previous study in which [Tyr(OMe)5]GnRH was shown to have reduced potency compared to GnRH. A novel GnRH peptide containing Tyr(OMe)5 andd-Glu6 in combination with other substitutions at positions 9 and 10 was synthesized in the present study and tested for binding to the rat pituitary as well as potency in terms of gonadotropin (GtH) release in the goldfish pituitary and ovulation in sea bass. The results demonstrate that the replacement of the glycine residue at position 6 with ad-Glu in combination with the substitution of proline at position 9 with azetidine (Aze) increased the binding and biological activity of [Tyr(OMe)5]GnRH. The observed increased potency is likely to be related to the improved resistance to degradation. The present findings may lead to the development of a more potent GnRH agonist for inducing ovulation in fish. 相似文献
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Morteza Djamali Matthew D. Jones Jérémy Migliore Silvia Balatti Marianela Fader Daniel Contreras Sébastien Gondet Zahra Hosseini Hamid Lahijani Abdolmajid Naderi Lyudmila S. Shumilovskikh Margareta Tengberg Lloyd Weeks 《Vegetation History and Archaeobotany》2016,25(3):255-269
Ancient Persia witnessed one of its most prosperous cultural and socio-economic periods between 550 bc and ad 651, with the successive domination of the Achaemenid, Seleucid, Parthian and Sassanian Empires. During this period agricultural activities increased on the Iranian plateau, as demonstrated by a remarkable arboricultural expansion. However, available data are not very informative about the spatial organization of agricultural practices. The possible links between climate conditions and agricultural activities during this millennium of continuous imperial domination are also unclear, due to the lack of parallel human-independent palaeoclimatic proxies. This study presents a new late Holocene pollen-based vegetation record from Lake Parishan, SW Iran. This record provides invaluable information regarding anthropogenic activities before, during and after the empires and sheds light on (i) spatial patterning in agricultural activities and (ii) possible climate impacts on agro-sylvo-pastoral practices during this period. Results of this study indicate that arboriculture was the most prominent form of agricultural activity in SW Iran especially during the Achaemenid, Seleucid and Parthian periods. Contrary to the information provided by some Greco-Roman written sources, the record from Lake Parishan shows that olive cultivation was practiced during Achaemenid and Seleucid times, when olive cultivation was significant, at least in this basin located close to the capital area of the Achaemenid Empire. In addition, pollen from aquatic vegetation suggests that the period of the latter centuries of the first millennium bc was characterized by a higher lake level, which might have favoured cultural and socio-economic prosperity. 相似文献
998.
George Japoshvili Hamid Rakhshani Jahangir Khajehali 《Zoology in the Middle East.》2016,62(3):261-264
Copidosoma isfahan Japoshvili sp. n. (Hymenoptera: Chalcidoidea: Encyrtidae), a parasitoid of Altenia mersinella (Staudinger, 1879) (Lepidoptera: Gelechiidae) on pistachio (Pistacia vera L.) is described and illustrated from Iran.
http://www.zoobank.org/urn:lsid:zoobank.org:pub:F1BCFE50-AD05-40BB-A2AC-2AF86956FE5F 相似文献
999.
Justin T. Page Zach S. Liechty Rich H. Alexander Kimberly Clemons Amanda M. Hulse-Kemp Hamid Ashrafi Allen Van Deynze David M. Stelly Joshua A. Udall 《PLoS genetics》2016,12(5)
Allotetraploid cotton species are a vital source of spinnable fiber for textiles. The polyploid nature of the cotton genome raises many evolutionary questions as to the relationships between duplicated genomes. We describe the evolution of the cotton genome (SNPs and structural variants) with the greatly improved resolution of 34 deeply re-sequenced genomes. We also explore the evolution of homoeologous regions in the AT- and DT-genomes and especially the phenomenon of conversion between genomes. We did not find any compelling evidence for homoeologous conversion between genomes. These findings are very different from other recent reports of frequent conversion events between genomes. We also identified several distinct regions of the genome that have been introgressed between G. hirsutum and G. barbadense, which presumably resulted from breeding efforts targeting associated beneficial alleles. Finally, the genotypic data resulting from this study provides access to a wealth of diversity sorely needed in the narrow germplasm of cotton cultivars. 相似文献
1000.
Mahboobeh Ziaei Mostafa Motallebi Mohammad Reza Zamani Nasim Zarin Panjeh 《Biotechnology letters》2016,38(6):1021-1032