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991.
992.
Yuri Miura Noritaka Hashii Yuki Ohta Yoko Itakura Hiroki Tsumoto Junya Suzuki Daisuke Takakura Yukiko Abe Yasumichi Arai Masashi Toyoda Nana Kawasaki Nobuyoshi Hirose Tamao Endo 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(6):1462-1471
Background
Glycosylation is highly susceptible to changes of the physiological conditions, and accordingly, is a potential biomarker associated with several diseases and/or longevity. Semi-supercentenarians (SSCs; older than 105?years) are thought to be a model of human longevity. Thus, we performed glycoproteomics using plasma samples of SSCs, and identified proteins and conjugated N-glycans that are characteristic of extreme human longevity.Methods
Plasma proteins from Japanese semi-supercentenarians (SSCs, 106–109?years), aged controls (70–88?years), and young controls (20–38?years) were analysed by using lectin microarrays and liquid chromatography/mass spectrometry (LC/MS). Peak area ratios of glycopeptides to corresponding normalising peptides were subjected to orthogonal projections to latent structures discriminant analysis (OPLS-DA). Furthermore, plasma levels of clinical biomarkers were measured.Results
We found two lectins such as Phaseolus vulgaris, and Erythrina cristagalli (ECA), of which protein binding were characteristically increased in SSCs. Peak area ratios of ECA-enriched glycopeptides were successfully discriminated between SSCs and controls using OPLS-DA, and indicated that tri-antennary and sialylated N-glycans of haptoglobin at Asn207 and Asn211 sites were characterized in SSCs. Sialylated glycans of haptoglobin are a potential biomarker of several diseases, such as hepatocellular carcinoma, liver cirrhosis, and IgA-nephritis. However, the SSCs analysed here did not suffer from these diseases.Conclusions
Tri-antennary and sialylated N-glycans on haptoglobin at the Asn207 and Asn211 sites were abundant in SSCs and characteristic of extreme human longevity.General significance
We found abundant glycans in SSCs, which may be associated with human longevity. 相似文献993.
Genetic characterization of hemagglutinin protein of measles viruses in Hokkaido district,Japan, 2006–2015
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Masahiro Miyoshi Rika Komagome Hiroki Yamaguchi Setsuko Ishida Hideki Nagano Motohiko Okano 《Microbiology and immunology》2018,62(6):411-417
994.
In vivo effect of a TLR5 SNP (C1205T) on Salmonella enterica serovar Typhimurium infection in weaned,specific pathogen‐free Landrace piglets
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Yoshihiro Muneta Nobuo Arai Yoko Yakabe Masahiro Eguchi Tomoyuki Shibahara Akiko Sakuma Hiroki Shinkai Hirohide Uenishi Kensuke Hirose Masato Akiba 《Microbiology and immunology》2018,62(6):380-387
995.
Hidenobu Murafuji Hiroki Sakai Megumi Goto Yoshiaki Oyama Seiichi Imajo Hajime Sugawara Toshiyuki Tomoo Tsuyoshi Muto 《Bioorganic & medicinal chemistry letters》2018,28(8):1371-1375
A novel series of 1,3,6-trisubstituted 1,4-diazepan-7-ones were investigated as human kallikrein 7 (KLK7, stratum corneum chymotryptic enzyme) inhibitors. Based on the X-ray co-crystal structure of compound 1 bound to human KLK7, the derivatives of this scaffold were designed, synthesized, and evaluated. Through structure-activity relationship studies focused on the side chain located in the prime site region of the enzyme, representative compounds 15, 33a, and 35a were identified as highly potent and selective inhibitors of human KLK7. 相似文献
996.
Shoi Shi Hiroki R. Ueda 《BioEssays : news and reviews in molecular, cellular and developmental biology》2018,40(1)
Although we are beginning to understand the neuronal and biochemical nature of sleep regulation, questions remain about how sleep is homeostatically regulated. Beyond its importance in basic physiology, understanding sleep may also shed light on psychiatric and neurodevelopmental disorders. Recent genetic studies in mammals revealed several non‐secretory proteins that determine sleep duration. Interestingly, genes identified in these studies are closely related to psychiatric and neurodevelopmental disorders, suggesting that the sleep‐wake cycle shares some common mechanisms with these disorders. Here we review recent sleep studies, including reverse and forward genetic studies, from the perspectives of sleep duration and homeostasis. We then introduce a recent hypothesis for mammalian sleep in which the fast and slow Ca2+‐dependent hyperpolarization pathways are pivotal in generating the SWS firing pattern and regulating sleep homeostasis, respectively. Finally, we propose that these intracellular pathways are potential therapeutic targets for achieving depolarization/hyperpolarization (D/H) balance in psychiatric and neurodevelopmental disorders. 相似文献
997.
Hiroki Maeda Takeshi Hatta Daigo Tsubokawa Fusako Mikami Toshiyuki Nishimaki Takeshi Nakamura Makoto Matsubayashi Motoyuki Ogawa Clarissa Prazeres da Costa Naotoshi Tsuji 《Parasitology international》2018,67(5):609-611
Parasite-induced behavioral changes in their hosts favor to complete the lifecycle of parasites. Schistosome infection is also known to cause physiological changes in infected freshwater snail intermediate hosts. Here, we report, a novel phenomenon in which Schistosoma mansoni, a highly debilitating worm affecting millions of people worldwide, alters the phototropic behavior of Biomphalaria glabrata, the vector snail. S. mansoni-infection enhanced positive phototropism of vector snails and infected snails spent significantly more time in light. Possibly, these behavioral changes help the parasite to be released efficiently from the infected intermediate hosts, and to infect mammalian hosts. 相似文献
998.
999.
Summary The populations of cells which produce immunoreactive growth hormone (GH) and thyroid stimulating hormone (TSH) in the rat
pituitary gland do not occur in fixed percentages but vary greatly under different physiological and experimental conditions.
These variations can be directly correlated to the levels of stimulation and/or inhibition of the specific secretory activity.
In both types of cell, sustained stimulation with trophic hormones or blockage of the feedback mechanisms induces remarkable
growth in the specific cell population. Conversely, the interruption or inhibition of the stimulus thwarted the hormonal secretion
and caused a massive degeneration of redundant cells. The stimulation of both GH and TSH cells is accompanied by an enhanced
secretory activity as judged by their higher concentrations in serum and hypertrophy of the cytoplasmic organelles involved
in synthesis and intracellular processing of the hormones. By contrast, interruption of the stimulus is followed by a variable
degree of disruption of the cytoplasmic organization, including a sizable degeneration of cells. In stimulated rats, the concentrations
of both GH and TSH decreased significantly in pituitary tissue due to mobilization of the hormonal stores contained in secretory
granules. On the other hand, the withdrawal of stimuli blocked the hormonal release; this is reflected by the accumulation
of both hormones and secretory granules in pituitary tissue. The strict correlation between the size of the GH and TSH populations
with stimulation and inhibition of hormonal secretory activity reported in this investigation further supports the critical
role played by the cell renewal process in endocrine secretion. 相似文献
1000.
A new cis-acting element for RNA replication within the 5' noncoding region of poliovirus type 1 RNA. 总被引:4,自引:2,他引:2
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Mouse cells expressing the human poliovirus receptor (PVR-mouse cells) as well as human HeLa cells are susceptible to poliovirus type 1 Mahoney strains and produce a large amount of progeny virus at 37 degrees C. However, the virus yield is markedly reduced at 40 degrees C in PVR-mouse cells but not in HeLa cells. The reduction in virus yield at 40 degrees C appears to be due to a defective initiation process in positive-strand RNA synthesis (K. Shiroki, H. Kato, S. Koike, T. Odaka, and A. Nomoto, J. Virol. 67:3989-3996, 1993). To gain insight into the molecular mechanisms involved in this detective process, naturally occurring heat-resistant (Hr)-mutants which show normal growth ability in PVR-mouse cells even at 40 degrees C were isolated from a virus stock of the Mahoney strain and their mutation sites that affect the phenotype were identified. The key mutation was a change from adenine (A) to guanine (G) at nucleotide position (nt) 133 within the 5' noncoding region of the RNA. This mutation also gave an Hr phenotype to the viral plus-strand RNA synthesis in PVR-mouse cells. Mutant Mahoney strains with a single point mutation at nt 133 (A to G, C, or T or deletion) were investigated for their ability to grow in PVR-mouse cells at 40 degrees C. Only the mutant carrying G at nt 133 showed an Hr growth phenotype in PVR-mouse cells. These results suggest that a host cellular factor(s) interacts with an RNA segment around nt 133 of the plus-strand RNA or the corresponding region of the minus-strand RNA, contributing to efficiency of plus-strand RNA synthesis. 相似文献