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151.
Intra-sexual dimorphism is found in the weapons of many male beetles. Different behavioral tactics to access females between
major and minor males, which adopt fighting and alternative tactics, respectively, are thought to maintain the male dimorphism.
In these species major males have enlarged weapons that they use in fights with rival males. Minor males also have small weapons
in some of these species, and it is unclear why these males possess weapons. We examined the hypothesis that minor males might
adopt a fighting tactic when their status was relatively high in comparison with that of other males (e.g., ownership of a
territory). We observed the behavioral tactics of major and minor males of the beetle Librodor japonicus, whose males have a dimorphism of their mandibles. Major males fought for resources, whereas minor males adopted two status-dependent
tactics, fighting and sneaking, to access females, depending on their ownership of a sap site. We suggest that ownership status-dependent
mating tactics in minor males may maintain the intra-sexual dimorphism in this beetle. 相似文献
152.
Inamori Y Ota M Inoko H Okada E Nishizaki R Shiota T Mok J Oka A Ohno S Mizuki N 《Human genetics》2007,122(2):151-157
The collagen type Ι alpha Ι (COL1A1) gene encodes the extracellular matrix component, collagen, and resides in candidate MYP5
for high myopia on the chromosome 17q22–q23.3. This locus has recently been implicated in playing an important role in the
pathogenesis of experimental myopia. We investigated the association of disruptions of COL1A1 gene with high myopia by analyzing the frequency of ten SNPs in a Japanese population of 330 subjects with high myopia of
−9.25 D or less and 330 randomized controls without high myopia. Two SNPs (rs2075555 and rs2269336) were significantly associated
with high myopia (P < 0.05, Pc < 0.1). Two different haplotype blocks in COL1A1 were observed by the pair-wise linkage disequilibrium between the SNPs. The frequency of GGC/GGC diplotype constructed by
the three SNPs (rs2075555, rs2269336, rs1107946) was significantly high (OR = 1.6) and associated with high myopia (P = 0.028, Pc< 0.084). Together our results provide the first evidence for COL1A1 as a gene associated with high myopia. 相似文献
153.
Maruyama T Yamamoto Y Kano Y Kurazono M Matsuhisa E Takata H Takata T Atsumi K Iwamatsu K Shitara E 《Bioorganic & medicinal chemistry》2007,15(19):6379-6387
A new series of 1beta-methyl carbapenems possessing a 6,7-disubstituted imidazo[5,1-b]thiazol-2-yl group directly attached to the C-2 position of the carbapenem nucleus was prepared, and the activities of these compounds against methicillin-resistant Staphylococcus aureus (MRSA) were evaluated. To study the effect of basic moieties on anti-MRSA activity, we introduced an amino, or imino, or amidino group at the 6-position of imidazo[5,1-b]thiazole in place of the carbamoylmethyl moiety of CP5068. Anti-MRSA activities of almost all basic group-substituted carbapenems were improved, though some of the compounds showed stronger acute toxicity in mice than IPM. In order to decrease the toxicity without decreasing the activity, we introduced various additional functionalities around the basic moiety. Finally, we obtained CP5484, which has excellent anti-MRSA activity and low acute toxicity. 相似文献
154.
Kawai A Nishida-Umehara C Ishijima J Tsuda Y Ota H Matsuda Y 《Cytogenetic and genome research》2007,117(1-4):92-102
Recent progress of chicken genome projects has revealed that bird ZW and mammalian XY sex chromosomes were derived from different autosomal pairs of the common ancestor; however, the evolutionary relationship between bird and reptilian sex chromosomes is still unclear. The Chinese soft-shelled turtle (Pelodiscus sinensis) exhibits genetic sex determination, but no distinguishable (heteromorphic) sex chromosomes have been identified. In order to investigate this further, we performed molecular cytogenetic analyses of this species, and thereby identified ZZ/ZW-type micro-sex chromosomes. In addition, we cloned reptile homologues of chicken Z-linked genes from three reptilian species, the Chinese soft-shelled turtle and the Japanese four-striped rat snake (Elaphe quadrivirgata), which have heteromorphic sex chromosomes, and the Siam crocodile (Crocodylus siamensis), which exhibits temperature-dependent sex determination and lacks sex chromosomes. We then mapped them to chromosomes of each species using FISH. The linkage of the genes has been highly conserved in all species: the chicken Z chromosome corresponded to the turtle chromosome 6q, snake chromosome 2p and crocodile chromosome 3. The order of the genes was identical among the three species. The absence of homology between the bird Z chromosome and the snake and turtle Z sex chromosomes suggests that the origin of the sex chromosomes and the causative genes of sex determination are different between birds and reptiles. 相似文献
155.
Journal of Ethology - Males of the Japanese scorpionfly, Panorpa japonica, often perform male–male competitions for food to offer to females as a nuptial gift. Previous studies have suggested... 相似文献
156.
Journal of Ethology - Circadian rhythm is an important factor for long-distance movement in insect species. Previous studies have shown the relationship between movement and circadian rhythm,... 相似文献
157.
158.
159.
The molecular interaction of a protein in highly concentrated solution investigated by Raman spectroscopy
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We used Raman spectroscopy to investigate the structure and interactions of lysozyme molecules in solution over a wide range of concentrations (2.5–300 mg ml?1). No changes in the amide‐I band were observed as the concentration was increased, but the width of the Trp band at 1555 cm?1 and the ratios of the intensities of the Tyr bands at 856 and 837 cm?1, the Trp bands at 870 and 877 cm?1, and the bands at 2940 (CH stretching) and 3420 cm?1 (OH stretching) changed as the concentration was changed. These results reveal that although the distance between lysozyme molecules changed by more than an order of magnitude over the tested concentration range, the secondary structure of the protein did not change. The changes in the molecular interactions occurred in a stepwise process as the order of magnitude of the distance between molecules changed. These results suggest that Raman bands can be used as markers to investigate the behavior of high‐concentration solutions of proteins and that the use of Raman spectroscopy will lead to progress in our understanding not only of the basic science of protein behavior under concentrated (i.e., crowded) conditions but also of practical processes involving proteins, such as in the field of biopharmaceuticals. © 2014 Wiley Periodicals, Inc. Biopolymers 103: 237–246, 2015. 相似文献
160.
Influence of Prostate Stem Cell Antigen Gene Polymorphisms on Susceptibility to Helicobacter pylori‐associated Diseases: A Case‐control Study
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