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161.
Takada T Shitara H Matsuoka K Kojima E Ishii R Kikkawa Y Taya C Karasuyama H Kohno K Yonekawa H 《Transgenic research》2008,17(6):1155-1162
Current mouse models for atopic dermatitis (AD) have a serious drawback, being the existence of dense hair on the body. Thus,
a hairless animal model on an AD-prone genetic background will be a powerful tool to investigate the basis of and therapy
for this complex disease. We applied the Toxin Receptor-mediated Cell Knockout (TRECK) method to generate a hairless transgenic
(Tg) mice on the NC/Nga background, an AD-prone inbred strain. A minigene with the mouse Keratin71 (Krt71) promoter and human diphtheria toxin receptor, which intrinsically functions as the heparin-binding EGF-like growth factor,
was introduced into the pronucleus of NC/Nga oocytes. Unexpectedly NCN24, one NC/Nga Tg line, showed a dominant hairless phenotype
without diphtheria toxin administration. Furthermore, the atopic dermatitis-like predisposition and IgE elevation was observed
in both NCN24 and the NC/Nga wildtype strain. NCN24 mice, which we have newly developed, will be useful to assess drugs for
AD therapy, being able to monitor skin inflammation without shaving.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
162.
163.
Kuroki A Toda T Matsui K Uotsu-Tomita R Tomita M Itaya M 《Journal of biochemistry》2008,143(1):97-105
The genome of Bacillus subtilis 168 was modified to yield a genome vector for the cloning of DNA several Mb in size. Unlike contemporary plasmid-based vectors, this 4.2 Mb genome vector requires specific in vivo handling protocols because of its large size. Inversion mutagenesis, a method to modify local genome structure without gain or loss of genes, was applied intensively to the B. subtilis genome; this technique made possible both exchange and translocation of designated regions of the genome. This method not only reshuffles the genome of B. subtilis, but can provide insight into the biologic principles underlying genome plasticity. 相似文献
164.
Kondou Y Higuchi M Takahashi S Sakurai T Ichikawa T Kuroda H Yoshizumi T Tsumoto Y Horii Y Kawashima M Hasegawa Y Kuriyama T Matsui K Kusano M Albinsky D Takahashi H Nakamura Y Suzuki M Sakakibara H Kojima M Akiyama K Kurotani A Seki M Fujita M Enju A Yokotani N Saitou T Ashidate K Fujimoto N Ishikawa Y Mori Y Nanba R Takata K Uno K Sugano S Natsuki J Dubouzet JG Maeda S Ohtake M Mori M Oda K Takatsuji H Hirochika H Matsui M 《The Plant journal : for cell and molecular biology》2009,57(5):883-894
Ectopic gene expression, or the gain-of-function approach, has the advantage that once the function of a gene is known the gene can be transferred to many different plants by transformation. We previously reported a method, called FOX hunting, that involves ectopic expression of Arabidopsis full-length cDNAs in Arabidopsis to systematically generate gain-of-function mutants. This technology is most beneficial for generating a heterologous gene resource for analysis of useful plant gene functions. As an initial model we generated more than 23 000 independent Arabidopsis transgenic lines that expressed rice fl-cDNAs (Rice FOX Arabidopsis lines). The short generation time and rapid and efficient transformation frequency of Arabidopsis enabled the functions of the rice genes to be analyzed rapidly. We screened rice FOX Arabidopsis lines for alterations in morphology, photosynthesis, element accumulation, pigment accumulation, hormone profiles, secondary metabolites, pathogen resistance, salt tolerance, UV signaling, high light tolerance, and heat stress tolerance. Some of the mutant phenotypes displayed by rice FOX Arabidopsis lines resulted from the expression of rice genes that had no homologs in Arabidopsis . This result demonstrated that rice fl-cDNAs could be used to introduce new gene functions in Arabidopsis. Furthermore, these findings showed that rice gene function could be analyzed by employing Arabidopsis as a heterologous host. This technology provides a framework for the analysis of plant gene function in a heterologous host and of plant improvement by using heterologous gene resources. 相似文献
165.
166.
Rie Miyauchi Katsuhiro Kawakami Masao Ito Norikazu Matsuhashi Hitoshi Ohki Hiroaki Inagaki Hisashi Takahashi Makoto Takemura 《Bioorganic & medicinal chemistry》2009,17(19):6879-6889
A series of novel 6-desfluoro [des-F(6)] and 6-fluoro-1-[(1R,2S)-2-fluorocyclopropan-1-yl]-8-methoxyquinolones bearing 3-(1-aminocycloalkyl)pyrrolidin-1-yl substituents at the C-7 position (1–6) was synthesized to obtain potent drugs for nosocomial infections caused by Gram-positive pathogens. The des-F(6) compounds 4–6 exhibited at least four times more potent activity against representative Gram-positive bacteria than ciprofloxacin or moxifloxacin. Among the derivatives, 7-[(3R)-3-(1-aminocyclopropan-1-yl)pyrrolidin-1-yl] derivative 4, which showed favorable profiles in preliminary toxicological and non-clinical pharmacokinetic studies, exhibited potent antibacterial activity against clinically isolated Gram-positive pathogens that had become resistant to one or more antibiotics. 相似文献
167.
C.S. Hernández-Rodríguez A. Boets J. Van Rie J. Ferré 《Journal of applied microbiology》2009,107(1):219-225
Aims: To identify known vip genes and to detect potentially novel vip genes in a collection of 507 strains of Bacillus thuringiensis .
Methods and Results: Following a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) strategy, four restriction patterns were found within the vip1 family: vip1Aa1 , vip1Ba1 / vip1Ba2 and vip1Ca . In the screening of vip2 genes, patterns similar to those of vip2Aa1 , vip2Ba1 / vip2Ba2 and vip2Ac1 genes were observed. Patterns for vip3Aa1 , vip3Ae2 and vip3Af1 were found among vip3 genes. Two new patterns revealed novel vip1 and vip3A genes. The observed frequency of genes belonging to vip1 and vip2 families was around 10%, whereas 48·9% of the strains showed amplification of vip3 genes. A tendency of vip and cry genes to occur together has been observed in this collection of B. thuringiensis strains.
Conclusions: Ten different patterns of vip genes belonging to the three vip families and two novel vip genes have been identified in this study.
Significance and Impact of the Study: This is the first time that vip1 and vip2 genes have been identified by PCR-RFLP. Furthermore, the results show that the strategy used in this study can lead to the classification of known vip genes as well as the identification of novel vip genes. 相似文献
Methods and Results: Following a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) strategy, four restriction patterns were found within the vip1 family: vip1Aa1 , vip1Ba1 / vip1Ba2 and vip1Ca . In the screening of vip2 genes, patterns similar to those of vip2Aa1 , vip2Ba1 / vip2Ba2 and vip2Ac1 genes were observed. Patterns for vip3Aa1 , vip3Ae2 and vip3Af1 were found among vip3 genes. Two new patterns revealed novel vip1 and vip3A genes. The observed frequency of genes belonging to vip1 and vip2 families was around 10%, whereas 48·9% of the strains showed amplification of vip3 genes. A tendency of vip and cry genes to occur together has been observed in this collection of B. thuringiensis strains.
Conclusions: Ten different patterns of vip genes belonging to the three vip families and two novel vip genes have been identified in this study.
Significance and Impact of the Study: This is the first time that vip1 and vip2 genes have been identified by PCR-RFLP. Furthermore, the results show that the strategy used in this study can lead to the classification of known vip genes as well as the identification of novel vip genes. 相似文献
168.
Yusuke Iwasaki Yusuke Saito Yuki Nakano Keisuke Mochizuki Osamu Sakata Rie Ito Koichi Saito Hiroyuki Nakazawa 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2009,877(28):3309-3317
Biological thiol compounds are classified into high-molecular-mass protein thiols and low-molecular-mass free thiols. Endogenous low-molecular-mass thiol compounds, namely, reduced glutathione (GSH) and its corresponding disulfide, glutathione disulfide (GSSG), are very important molecules that participate in a variety of physiological and pathological processes. GSH plays an essential role in protecting cells from oxidative and nitrosative stress and GSSG can be converted into the reduced form by action of glutathione reductase. Measurement of GSH and GSSG is a useful indicator of oxidative stress and disease risk. Many publications have reported successful determination of GSH and GSSG in biological samples. In this article, we review newly developed techniques, such as liquid chromatography coupled with mass spectrometry and tandem mass spectrometry, for identifying GSH bound to proteins, or for localizing GSH in bound or free forms at specific sites in organs and in cellular locations. 相似文献
169.
Kurihara K Shinei R Tanabe K Tabata Y Kurata Y Hoshiko S Okonogi T 《Bioorganic & medicinal chemistry》2006,14(14):4862-4878
The human progesterone receptor (PR) binding affinity and the PR agonistic or antagonistic potency of tetrahydronaphthofuranone derivatives were shown previously to be markedly influenced by substituents at the 6- and 7-positions. Here, we synthesized tetrahydrobenzindolones possessing a lactam ring, which enabled us to modify the 6- and 7-positions more freely, since tetrahydrobenzindolones are chemically more stable than tetrahydronaphthofuranones. The tetrahydrobenzindolone derivatives generally showed higher PR binding affinity than the corresponding tetrahydronaphthofuranones. We also succeeded in separating the agonistic and antagonistic activities by choosing suitable substituent groups at the 6- and/or 7-position(s) of the tetrahydrobenzindolone. The effects of representative agonists, 12c (CP8668), and 14a (CP8816), and a representative antagonist, 15f (CP8661), were confirmed in in vivo tests. In this report, we mainly describe the synthesis and structure-activity relationships (SAR) of tetrahydrobenzindolone derivatives, as new nonsteroidal PR ligands. 相似文献
170.
Indirect reciprocity is one mechanism that allows for unilateral resource giving among n-persons. Using analytical methods and computer simulations, previous studies have examined a number of strategies that make indirect reciprocity possible. In particular, previous investigations have concentrated on whether differentiating between justified and unjustified not-giving is important. However, whether or not a given strategy is ESS depends on the type of perceptual errors that are assumed. When errors are objective, regarding those who do not give to "bad" as "good" is critical. When perceptual errors are subjective, however, regarding those who give to "bad" as "bad" is critical. Since we believe that there is no guarantee that perceptual errors are shared among all individuals in a society, we argue that the latter moral principle may play a more important role in human interactions. 相似文献