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141.
Reciprocal questions often frame studies of the evolution of developmental mechanisms. How can species share similar developmental genetic toolkits but still generate diverse life forms? Conversely, how can similar forms develop from different toolkits? Genomics bridges the gap between evolutionary and developmental biology, and can help answer these evo-devo questions in several ways. First, it informs us about historical relationships, thus orienting the direction of evolutionary diversification. Second, genomics lists all toolkit components, thereby revealing contraction and expansion of the genome and suggesting mechanisms for evolution of both developmental functions and genome architecture. Finally, comparative genomics helps us to identify conserved non-coding elements and their relationship to genome architecture and development. 相似文献
142.
The spider suborder Mesothelae, containing a single extant family Liphistiidae, represents a species-poor and ancient lineage. These are conspicuous spiders that primitively retain a segmented abdomen and appendage-like spinnerets. While their classification history is nearly devoid of phylogenetic hypotheses, we here revise liphistiid genus level taxonomy based on original sampling throughout their Asian range, and on the evidence from a novel molecular phylogeny. By combining morphological and natural history evidence with phylogenetic relationships in the companion paper, we provide strong support for the monophyly of Liphistiidae, and the two subfamilies Liphistiinae and Heptathelinae. While the former only contains Liphistius Schiödte, 1849, a genus distributed in Indonesia (Sumatra), Laos, Malaysia, Myanmar, Thailand, we recognize and diagnose seven heptatheline genera, all but three removed from the synonymy of Heptathela: i) Ganthela Xu & Kuntner, gen. n. with the type species Ganthela
yundingensis Xu, sp. n. is known from Fujian and Jiangxi, China; ii) a rediagnosed Heptathela Kishida, 1923 is confined to the Japanese islands (Kyushu and Okinawa); iii) Qiongthela Xu & Kuntner, gen. n. with the type species Qiongthela
baishensis Xu, sp. n. is distributed disjunctly in Hainan, China and Vietnam; iv) Ryuthela Haupt, 1983 is confined to the Ryukyu archipelago (Japan); v) Sinothela Haupt, 2003 inhabits Chinese areas north of Yangtze; vi) Songthela Ono, 2000 inhabits southwest China and northern Vietnam; and vii) Vinathela Ono, 2000 (Abcathela Ono, 2000, syn. n.; Nanthela Haupt, 2003, syn. n.) is known from southeast China and Vietnam. 相似文献
143.
This study presents a fundamental concept of piezomagnetic biochemical sensor driven in a wireless-electrodeless manner. A stepped cylindrical rod of nickel is used as the oscillator, which traps the vibrational energy of axially-polarized surface-shear waves in the central part, where the diameter is slightly larger. A meander-line coil surrounding the oscillator with an air gap can cause and detect the resonant vibrations of the surface-shear waves via the piezomagnetic effect. The resonant frequency of the trapped-mode resonance is continuously measured to detect human immunoglobulin G (IgG). It decreased by 0.08% when a solution containing IgG was injected into the glass cell where the oscillator was placed alone. This oscillator is useful for fundamental studies of various biochemical reactions in a closed system in different environmental gases and different pressures. 相似文献
144.
Tetsuro Yoshida Kimihiko Kato Tetsuo Fujimaki Kiyoshi Yokoi Mitsutoshi Oguri Sachiro Watanabe Norifumi Metoki Hidemi Yoshida Kei Satoh Yukitoshi Aoyagi Yutaka Nishigaki Masashi Tanaka Yoshinori Nozawa Yoshiji Yamada 《Genomics》2009,93(3):221-226
The purpose of the present study was to identify genetic variants that confer susceptibility to chronic kidney disease (CKD) in Japanese individuals with metabolic syndrome. The study population comprised 2150 Japanese individuals with metabolic syndrome, including 411 subjects with CKD [estimated glomerular filtration rate (eGFR) < 50 mL/min/1.73m2] and 1739 controls (eGFR ≥ 60 mL/min/1.73m2). The genotypes for 100 polymorphisms of 80 candidate genes were determined. The chi-square test, multivariable logistic regression analysis with adjustment for covariates, as well as a stepwise forward selection procedure revealed that nine polymorphisms of APOE, ABCA1, PTGS1, TNF, CPB2, AGTR1, OR13G1, and GNB3 were associated (P < 0.05) with the prevalence of CKD. Among these polymorphisms, the ? 219G → T polymorphism of APOE (rs405509) was most significantly associated with CKD in Japanese individuals with metabolic syndrome. 相似文献
145.
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147.
The promoter of an anther tapetum-specific gene,Osg6B, was fused to a-glucuronidase (GUS) gene and introduced into rice byAgrobacterium-mediated gene transfer. Fluorometric and histochemical GUS assay showed that GUS was expressed exclusively within the tapetum of anthers from the uninucleate microspore stage (7 days before anthesis) to the tricellular pollen stage (3 days before anthesis). This is the first demonstration of an anther-specific promoter directing tapetum-specific expression in rice.Abbreviations
GUS
ßGlucuronidase 相似文献
148.
Unlike other members of coagulase negative staphylococci (CNS), strain warneri has proMCD operon, a homologue of sspABC proteinase operon of S. aureus. The proM and proC encode serine glutamyl endopeptidase and cysteine protease respectively, whereas proD directs homologue of SspC, putative cytoplasmic inhibitor which protects the host bacterium from premature activation of SspB. We determined whole nucleotide sequence of proMCD operon of S. warneri M, succeeded in expression of these genes, and investigated their functions by gene inactivation and complementation experiments. In gelatin zymography of the culture supernatant, a 20-kDa band corresponding to PROC cysteine protease was detected. By Western blotting, PROD was also confirmed in the cytoplasmic protein fraction. PROC and PROD showed significant similarity to SspB and SspC of S. aureus (73% and 58%, respectively). Inactivation mutants of proMCD, proCD and proD genes were established, separately. In the proMCD mutant, degradation/processing of extracellular proteins was drastically reduced, suggesting that PROM was responsible for the cleavage of extracellular proteins. By the proD mutation, the growth profile was not affected, and secretion of PROC was retained. Extracellular protein profiles of the proCD and proD mutants were not so different each other, but autolysin profiles were slightly dissimilar, around 39–48 kDa and 20 kDa bands in zymogram. Experiments in buffer systems showed that autolysis was significantly diminished in proMCD mutant, and was promoted by addition of purified PROM. The proC gene was cloned into a multicopy plasmid, and introduced into the proMCD mutant. Compared with the wild type, autolysis of the proC-complemented strain was definitely enhanced by addition of purified PROM. These results suggested that PROM and PROC affected the coccal autolysis, through processing of the autolysin. 相似文献
149.
H Takeuchi I Yokoi A Mori M Kohsaka 《Comptes rendus des séances de la Société de biologie et de ses filiales》1975,169(4):1099-1105
Effects of the following amino acids were examined on the electrical activity of the two giant neurones (PON and TAN) identified in the subesophageal ganglia of Achatina fulica Férussac : L-Asp, L-Thr, L-Ser, L-Glu, L-Pro, Gly, L-alpha-Ala, beta-Ala, L-cysteine, L-cystine, L-Val, L-Met, L-Ileu, L-Leu, L-Tyr, L-Phe, L-Lys, L-His, L-Arg, L-Cit, L-Try, GABA and GABOB. Among these substances, we observed an inhibitory effect of GABA and GABOB on the TAN excitability. GABA showed stronger effect on the TAN than GABOB. This effect of GABA was due to producing hyperpolarization on the TAN membrane. GABA showed a slight excitatory effect on the PON. The effect of GABOB on the PON was very weak and unstable. 相似文献
150.
Fumiaki Yokoi Huan-Xin Chen Mai Tu Dang Chad C. Cheetham Susan L. Campbell Steven N. Roper J. David Sweatt Yuqing Li 《PloS one》2015,10(3)
DYT1 dystonia is an inherited movement disorder caused by mutations in DYT1 (TOR1A), which codes for torsinA. Most of the patients have a trinucleotide deletion (ΔGAG) corresponding to a glutamic acid in the C-terminal region (torsinAΔE). Dyt1 ΔGAG heterozygous knock-in (KI) mice, which mimic ΔGAG mutation in the endogenous gene, exhibit motor deficits and deceased frequency of spontaneous excitatory post-synaptic currents (sEPSCs) and normal theta-burst-induced long-term potentiation (LTP) in the hippocampal CA1 region. Although Dyt1 KI mice show decreased hippocampal torsinA levels, it is not clear whether the decreased torsinA level itself affects the synaptic plasticity or torsinAΔE does it. To analyze the effect of partial torsinA loss on motor behaviors and synaptic transmission, Dyt1 heterozygous knock-out (KO) mice were examined as a model of a frame-shift DYT1 mutation in patients. Consistent with Dyt1 KI mice, Dyt1 heterozygous KO mice showed motor deficits in the beam-walking test. Dyt1 heterozygous KO mice showed decreased hippocampal torsinA levels lower than those in Dyt1 KI mice. Reduced sEPSCs and normal miniature excitatory post-synaptic currents (mEPSCs) were also observed in the acute hippocampal brain slices from Dyt1 heterozygous KO mice, suggesting that the partial loss of torsinA function in Dyt1 KI mice causes action potential-dependent neurotransmitter release deficits. On the other hand, Dyt1 heterozygous KO mice showed enhanced hippocampal LTP, normal input-output relations and paired pulse ratios in the extracellular field recordings. The results suggest that maintaining an appropriate torsinA level is important to sustain normal motor performance, synaptic transmission and plasticity. Developing therapeutics to restore a normal torsinA level may help to prevent and treat the symptoms in DYT1 dystonia. 相似文献