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1.
Extraction of DNA from non-invasive samples (feces) has been used increasingly in genetic research on wildlife. For effective and reliable genetic analyses, knowledge about which samples should be selected in the field is essential. For this reason, we examined the process of DNA degradation in feces of deer. We collected fresh fecal pellets from three wild deer living in a warm temperate forest. We then assessed the effects of time (3, 5, and 10 days) under three environmental conditions (on the forest floor, on exposed ground, and inside the laboratory) on the rates of correct genotyping (CG), amplification failure (NA), genotyping error among positive amplification (ER), false alleles (FA), and allelic dropout (AD) of 15 microsatellite loci. The rate of CG significantly decreased, and those of NA and FA increased with increasing lapse of time. Rates of CG tended to be highest and those of NA, ER, FA, and AD to be lowest in feces kept inside, followed by those on the forest floor. Suitability of samples for DNA extraction was lowest in fecal pellets left on exposed ground, and we suspect that rain may hasten DNA degradation. NA rate could serve as a reliable indicator of the quality of fecal pellets because it was significantly positively correlated with ER rate. For efficient genetic analyses using deer feces in warm temperate zones, we recommend collecting fecal pellets within 3 days of defecation, during periods without rainfall and from under the cover of trees. 相似文献
2.
A putative GDP–GTP exchange factor is required for development of the excretory cell in Caenorhabditis elegans 下载免费PDF全文
Norio Suzuki Matthew Buechner Kiyoji Nishiwaki David H. Hall Hiroyuki Nakanishi Yoshimi Takai Naoki Hisamoto Kunihiro Matsumoto 《EMBO reports》2001,2(6):530-535
The Caenorhabditis elegans excretory cell extends tubular processes, called canals, along the basolateral surface of the epidermis. Mutations in the exc-5 gene cause tubulocystic defects in this canal. Ultrastructural analysis suggests that exc-5 is required for the proper placement of cytoskeletal elements at the apical epithelial surface. exc-5 encodes a protein homologous to guanine nucleotide exchange factors and contains motif architecture similar to that of FGD1, which is responsible for faciogenital dysplasia. exc-5 interacts genetically with mig-2, which encodes Rho GTPase. These results suggest that EXC-5 controls the structural organization of the excretory canal by regulating Rho family GTPase activities. 相似文献
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Yohei Sugano Yoshifumi Kawamura Naoki Goshima Naoki Morita Satoru Ohgiya 《Biotechnology letters》2010,32(10):1515-1521
Nucleotide sequences proximal to the initiation codon of a gene are known to affect the expression efficiency of that gene.
We screened 10-bp random sequences upstream of the initiation codon of the zeocin-resistance gene to identify sequences that
could enhance its expression in Saccharomyces cerevisiae. Of the isolated sequences, 20 sequences exhibited a common feature, i.e. ATG at the position −9 through −7, which resulted
in the incorporation of three amino acids at the N-terminus of the protein. The introduction of these sequences upstream of the initiation codon increased the expression levels
of zeocin-resistance protein by 2.2–6.5-fold. One of these sequences increased the expression levels of three out of four
human proteins, thereby suggesting that this sequence may also enhance the expression efficiency of mammalian proteins in
yeast. 相似文献
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Takumi Hiyoshi Hisanori Domon Tomoki Maekawa Kosuke Nagai Hikaru Tamura Naoki Takahashi Daisuke Yonezawa Tomohiro Miyoshi Akihiro Yoshida Koichi Tabeta Yutaka Terao 《Microbiology and immunology》2019,63(3-4):100-110
Aggregatibacter actinomycetemcomitans is considered to be associated with periodontitis. Leukotoxin (LtxA), which destroys leukocytes in humans, is one of this bacterium's major virulence factors. Amounts of neutrophil elastase (NE), which is normally localized in the cytoplasm of neutrophils, are reportedly increased in the saliva of patients with periodontitis. However, the mechanism by which NE is released from human neutrophils and the role of NE in periodontitis is unclear. In the present study, it was hypothesized that LtxA induces NE release from human neutrophils, which subsequently causes the breakdown of periodontal tissues. LtxA‐treatment did not induce significant cytotoxicity against human gingival epithelial cells (HGECs) or human gingival fibroblasts (HGFs). However, it did induce significant cytotoxicity against human neutrophils, leading to NE release. Furthermore, NE and the supernatant from LtxA‐treated human neutrophils induced detachment and death of HGECs and HGFs, these effects being inhibited by administration of an NE inhibitor, sivelestat. The present results suggest that LtxA mediates human neutrophil lysis and induces the subsequent release of NE, which eventually results in detachment and death of HGECs and HGFs. Thus, LtxA‐induced release of NE could cause breakdown of periodontal tissue and thereby exacerbate periodontitis. 相似文献
7.
Naoki Tokuhara Kana Namiki Mai Uesugi Chihiro Miyamoto Makoto Ohgoh Katsutoshi Ido Takashi Yoshinaga Toshihiko Yamauchi Junro Kuromitsu Sadao Kimura Norimasa Miyamoto Yoshitoshi Kasuya 《The Journal of biological chemistry》2010,285(43):33294-33306
One of the family of voltage-gated calcium channels (VGCC), the N-type Ca2+ channel, is located predominantly in neurons and is associated with a variety of neuronal responses, including neurodegeneration. A precise mechanism for how the N-type Ca2+ channel plays a role in neurodegenerative disease, however, is unknown. In this study, we immunized N-type Ca2+ channel α1B-deficient (α1B−/−) mice and their wild type (WT) littermates with myelin oligodendrocyte glycoprotein 35–55 and analyzed the progression of experimental autoimmune encephalomyelitis (EAE). The neurological symptoms of EAE in the α1B−/− mice were less severe than in the WT mice. In conjunction with these results, sections of the spinal cord (SC) from α1B−/− mice revealed a reduction in both leukocytic infiltration and demyelination compared with WT mice. No differences were observed in the delayed-type hypersensitivity response, spleen cell proliferation, or cytokine production from splenocytes between the two genotypes. On the other hand, Western blot array analysis and RT-PCR revealed that a typical increase in the expression of MCP-1 in the SC showed a good correlation with the infiltration of leukocytes into the SC. Likewise, immunohistochemical analysis showed that the predominant source of MCP-1 was activated microglia. The cytokine-induced production of MCP-1 in primary cultured microglia from WT mice was significantly higher than that from α1B−/− mice and was significantly inhibited by a selective N-type Ca2+ channel antagonist, ω-conotoxin GVIA or a withdrawal of extracellular Ca2+. These results suggest that the N-type Ca2+ channel is involved in the pathogenesis of EAE at least in part by regulating MCP-1 production by microglia. 相似文献
8.
Naoki Nishizawa Yoko Kanematsu-Yamaki Masaaki Funata Hiroaki Nagai Ayako Shimizu Hisashi Fujita Junichi Sakamoto Shiro Takekawa Taiji Asami 《Bioorganic & medicinal chemistry letters》2017,27(20):4626-4629
Neuromedin U (NMU) mediates various physiological functions via NMUR1 and NMUR2 receptors. NMUR2 has been considered a promising treatment option for diabetes and obesity. Although NMU-8, a shorter peptide, has potent agonist activity for both receptors, it is metabolically unstable. Therefore, NMU-8 analogs modified with long-chain alkyl moieties via a linker were synthesized. An octadecanoyl analog (17) with amino acid substitutions [αMePhe19, Nle21, and Arg(Me)24] and a linker [Tra-γGlu-PEG(2)] dramatically increased NMUR2 selectivity, with retention of high agonist activity. Subcutaneous administration of 17 induced anorectic activity in C57BL/6J mice. Owing to its high metabolic stability, 17 would be useful in clarifying the physiological role and therapeutic application of NMU. 相似文献
9.
Naoki Nishizawa Ayumu Niida Yusuke Adachi Yasushi Masuda Satoshi Kumano Kotaro Yokoyama Tomoko Asakawa Hideki Hirabayashi Nobuyuki Amano Shiro Takekawa Tetsuya Ohtaki Taiji Asami 《Bioorganic & medicinal chemistry letters》2017,27(16):3829-3832
The gastrointestinal peptide, peptide YY3–36 (PYY3–36) and its shorter peptide analogues have been reported to reduce appetite by activating the neuropeptide Y2 receptor (Y2R), which is associated with obesity and other metabolic diseases. A 14-amino acid PYY analogue, Ac-[d-Pro24,Cha27,28,36,Aib31]PYY(23–36) (3), showed high binding affinity and agonist activity for the Y2R, similar to that of PYY3–36, but had weak anorectic activity upon continuous administration in lean mice. Three amino acid substitutions [Pya(4)26, Aib28, Lys30], which contributed to the decreased hydrophobicity of 3, efficiently increased its anorectic activity. The compound containing these three amino acids, Ac-[d-Pro24,Pya(4)26,Cha27,36,Aib28,31,Lys30]PYY(23–36) (22), exerted more potent and durable food intake suppression than that by PYY3–36 in lean mice, as well as excellent Y2R agonist activity (EC50: 0.20 nM) and good subcutaneous bioavailability (66.6%). The 11-day continuous administration of 22 at 1 mg/kg/day successfully produced antiobese and antidiabetic effects, with more than 20% body weight loss in obese and Type 2 diabetes ob/ob model mice. 相似文献
10.
Association of a reactive intermediate derived from 1′,6‐dihydroxy metabolite with benzbromarone‐induced hepatotoxicity 下载免费PDF全文
Mina Yoshida Naoki Cho Hidetaka Akita Kaoru Kobayashi 《Journal of biochemical and molecular toxicology》2017,31(10)
Treatment with benzbromarone can be associated with liver injury, but the detailed mechanism remains unknown. Our recent studies demonstrated that benzbromarone was metabolized to 1′,6‐dihydroxybenzbromarone and followed by formation of reactive intermediates that were trapped by glutathione, suggesting that the reactive intermediates may be responsible for the liver injury. The aim of this study was to clarify whether the reactive intermediates derived from 1′,6‐dihydroxybenzbromarone is a risk factor of liver injury in mice. An incubation study using mouse liver microsomes showed that the rates of formation of 1′,6‐dihydroxybenzbromarone from benzbromarone were increased by pretreatment with dexamethasone. Levels of a hepatic glutathione adduct derived from 1′,6‐dihydroxybenzbromarone were increased by pretreatment with dexamethasone. Furthermore, plasma alanine amino transferase activities were increased in mice treated with benzbromarone after pretreatment with dexamethasone. The results suggest that the reactive intermediate derived from 1′,6‐dihydroxybenzbromarone may be associated with liver injury. 相似文献