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961.
K.-W. Cho Hwa-Young Youn Masaru Okuda Hitoshi Satoh Stanley Cevario Stephen J. O’Brien Toshihiro Watari Hajime Tsujimoto Atsuhiko Hasegawa 《Immunogenetics》1998,47(3):226-233
Molecular cloning and chromosomal mapping of the cat immunoglobulin (Ig) and T-cell receptor (TcR) genes were carried out to provide basic information for genetic analysis of immunologic diseases including leukemias and
lymphomas in cats. We cloned two Ig constant genes, IGHM and IGHG and three TcR constant genes, TRAC, TRGC, and TRDC, by polymerase chain reaction (PCR) amplification of cDNA from cat peripheral blood mononuclear cells. For chromosomal mapping
of the Ig and TcR loci including the IGK, IGL, and TRB on the cat genome, we performed PCR screening of DNAs from 37 cat × rodent somatic cell hybrids by using specific primers
for the given genes. Consequently, three loci for IGH, TRA, and TRD, and two loci for TRB and TRG were found to be syntenic and assigned to cat chromosomes (FCA) B3 and A2, respectively. Further, IGK and IGL loci were mapped on FCA A3 and D3, respectively. These findings support the notion that the genetic linkages between the
Ig and TcR genes are extensively conserved between humans and cats.
Received: 18 June 1997 / Revised: 12 August 1997 相似文献
962.
Conversion of NfsA, the Major Escherichia coli Nitroreductase, to a Flavin Reductase with an Activity Similar to That of Frp, a Flavin Reductase in Vibrio harveyi, by a Single Amino Acid Substitution 总被引:1,自引:0,他引:1
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Shuhei Zenno Toshiro Kobori Masaru Tanokura Kaoru Saigo 《Journal of bacteriology》1998,180(2):422-425
NfsA is the major oxygen-insensitive nitroreductase of Escherichia coli, similar in amino acid sequence to Frp, a flavin reductase of Vibrio harveyi. Here, we show that a single amino acid substitution at position 99, which may destroy three hydrogen bonds in the putative active center, transforms NfsA from a nitroreductase into a flavin reductase that is as active as the authentic Frp and a tartrazine reductase that is 30-fold more active than wild-type NfsA. 相似文献
963.
Ali M. Golmirzaie Rodomiro Ortiz Gary N. Atlin Masaru Iwanaga 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,97(7):1125-1128
True potato seed (TPS) may be an alternative method of potato production in developing countries. A breeding method for the
sexual propagation of this vegetatively propagated crop should consider the development of parental lines and the type of
cultivar to be released. Open-pollinated (OP) cultivars seem to be an inexpensive procedure to produce potato from true seed.
However, OP progenies are the result of selfing and outcrossing in male-fertile tetraploid potatoes. The aim of the present
research was to establish the effect of inbreeding and open pollination in TPS. Ten Andigena clones were used as parental material to derive hybrid (S0), inbred (S1 and S2), and open-pollinated (OP1 and OP2) generations. Significant differences among generations were found for pollen production, pollen viability (as determined
by its stainability with aceto-carmine glycerol), number of flowers and berries plant-1, number of seeds berry-1, weight of 1000 seeds, and tuber yield plant-1. The parental populations were significantly different for most of the traits, but not for flower production and berry weight.
The interaction of population ×generation was significant for pollen and seed production as well as for weight for 1000 seeds.
All the traits evaluated except seed weight showed a strong inbreeding depression, while the OP progenies had intermediate
values between the S0 and the S1. This demonstrates that open pollination in potatoes is not exclusively the product of selfing; it also results from outcrossing.
Received: 10 November 1997 / Accepted: 3 March 1998 相似文献
964.
Denitrification by Actinomycetes and Purification of Dissimilatory Nitrite Reductase and Azurin from Streptomyces thioluteus 总被引:1,自引:0,他引:1
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Hirofumi Shoun Mitsuyoshi Kano Ikuko Baba Naoki Takaya Masaru Matsuo 《Journal of bacteriology》1998,180(17):4413-4415
Many actinomycete strains are able to convert nitrate or nitrite to nitrous oxide (N2O). As a representative of actinomycete denitrification systems, the system of Streptomyces thioluteus was investigated in detail. S. thioluteus attained distinct cell growth upon anaerobic incubation with nitrate or nitrite with concomitant and stoichiometric conversion of nitrate or nitrite to N2O, suggesting that the denitrification acts as anaerobic respiration. Furthermore, a copper-containing, dissimilatory nitrite reductase (CuNir) and its physiological electron donor, azurin, were isolated. This is the first report to show that denitrification generally occurs among actinomycetes. 相似文献
965.
Yoshiaki Yonekawa Akihiro Harada Yasushi Okada Takeshi Funakoshi Yoshimitsu Kanai Yosuke Takei Sumio Terada Tetsuo Noda Nobutaka Hirokawa 《The Journal of cell biology》1998,141(2):431-441
The nerve axon is a good model system for studying the molecular mechanism of organelle transport in cells. Recently, the new kinesin superfamily proteins (KIFs) have been identified as candidate motor proteins involved in organelle transport. Among them KIF1A, a murine homologue of unc-104 gene of Caenorhabditis elegans, is a unique monomeric neuron– specific microtubule plus end–directed motor and has been proposed as a transporter of synaptic vesicle precursors (Okada, Y., H. Yamazaki, Y. Sekine-Aizawa, and N. Hirokawa. 1995. Cell. 81:769–780). To elucidate the function of KIF1A in vivo, we disrupted the KIF1A gene in mice. KIF1A mutants died mostly within a day after birth showing motor and sensory disturbances. In the nervous systems of these mutants, the transport of synaptic vesicle precursors showed a specific and significant decrease. Consequently, synaptic vesicle density decreased dramatically, and clusters of clear small vesicles accumulated in the cell bodies. Furthermore, marked neuronal degeneration and death occurred both in KIF1A mutant mice and in cultures of mutant neurons. The neuronal death in cultures was blocked by coculture with wild-type neurons or exposure to a low concentration of glutamate. These results in cultures suggested that the mutant neurons might not sufficiently receive afferent stimulation, such as neuronal contacts or neurotransmission, resulting in cell death. Thus, our results demonstrate that KIF1A transports a synaptic vesicle precursor and that KIF1A-mediated axonal transport plays a critical role in viability, maintenance, and function of neurons, particularly mature neurons. 相似文献
966.
Yukihiro Terada Seiichiro Nagai Tadashi Mabuchi Shuji Hirata Tomoko Shoda Tsuyoshi Kasai Kazuhiko Hoshi Sadaki Yokota Hiroshi Shitara Hiromichi Yonekawa Kaoru Yanagida Hideh Saito Koji Nakagawa Satoshi Kawachiya Wakako Iwasaki Mami Sato Megumu Ito Gabriera M. Ishida Yuji Takahashi Naoki Takeshita 《Human cell》2004,17(2):27-32
967.
Yasuo Shinohara Mohamad Radwan Almofti Takenori Yamamoto Taro Ishida Fumiyo Kita Hideki Kanzaki Masakatsu Ohnishi Kikuji Yamashita Shigeomi Shimizu Hiroshi Terada 《European journal of biochemistry》2002,269(21):5224-5230
To examine whether valinomycin induces a mitochondrial permeability transition (PT), we investigated its effects on mitochondrial functions under various conditions. The acceleration of mitochondrial respiration and swelling, induced by valinomycin, were found to be insensitive to inhibitors of the ordinary PT, indicating that valinomycin does not induce the ordinary PT. Results of experiments using mitochondria isolated from transgenic mice expressing human bcl-2 also supported this conclusion. Furthermore, evidence for induction of PT pores by valinomycin was not obtained by either electron microscopic analysis of mitochondrial configurations or by measurement of the permeability of the inner mitochondrial membrane by use of polyethylene glycol. However, valinomycin did induce a significant release of cytochrome c, and thus it may be a nice tool to study the processes of mitochondrial cytochrome c release. 相似文献
968.
Robert Shiurba Tatsuo Hirabayashi Masaru Masuda Akinori Kawamura Yuta Komoike William Klitz Keiichi Kinowaki Takashi Funatsu Shunzo Kondo Shin Kiyokawa Toshiro Sugai Kosuke Kawamura Hideo Namiki Toru Higashinakagawa 《Photochemical & photobiological sciences》2006,5(9):799-807
Infrared rays from sunlight permeate the earth's atmosphere, yet little is known about their interactions with living organisms. To learn whether they affect cell structure and function, we tested the ciliated protozoan, Tetrahymena thermophila. These unicellular eukaryotes aggregate in swarms near the surface of freshwater habitats, where direct and diffuse solar radiation impinge upon the water-air interface. We report that populations irradiated in laboratory cultures grew and mated normally, but major changes occurred in cell physiology during the stationary phase. Early on, there were significant reductions in chromatin body size and the antibody reactivity of methyl groups on lysine residues 4 and 9 in histone H3. Later, when cells began to starve, messenger RNAs for key proteins related to chromatin structure, intermediary metabolism and cellular motility increased from two- to nearly nine-fold. Metabolic activity, swimming speed and linearity of motion also increased, and spindle shaped cells with a caudal cilium appeared. Our findings suggest that infrared radiation enhances differentiation towards a dispersal cell-like phenotype in saturated populations of Tetrahymena thermophila. 相似文献
969.
K Haruta A Iguchi T Matsubara K Itoh C L Chen S Yoshida R Terada M Kanashiro O Suzuki H Nishimura 《Life sciences》1992,50(6):427-433
The injection of neostigmine into the hippocampus of anesthetized rats increased the mean arterial blood pressure (17% of baseline after 60 min injection) and decreased the heart rate (24% of baseline after 60 min injection). These changes were blocked by the co-administration of methylatropine into the hippocampus. Intrahippocampal injection of neostigmine stimulated the secretion of epinephrine and norepinephrine. Adrenodemedullation did not suppress the increase in blood pressure and the decrease in heart rate. It is concluded that the stimulation of muscarinic cholinoceptive neurons in the hippocampus evokes a hypertensive response via an increase in sympathetic drive to the heart and peripheral vasculature, with bradycardia possibly mediated via the parasympathetic system. 相似文献
970.
Katsuyuki Terada 《Mycoscience》1998,39(1):77-84
Six carabidicolous species of Laboulbeniales are reported as new for the Japanese mycoflora. They areDixomyces stomonaxi, Laboulbenia picardii, L. tenera, L. slackensis, L. aristata andL. kwangjuensis. Two forms ofD. stomonaxi are distinguished, one form of which resemblesD. nigromarginatus. A remarkable ornamentation consisting of a coillike pattern occurs on the receptacle ofL. picardii. InL. tenera andL. slackensis, the outer appendage has somewhat constricted, blackened septa near the base.Laboulbenia aristata andL. kwangjuensis have spirally arranged outer wall cells. Antheridia were observed inL. tenera, L. slackensis, L. aristata andL. kwangjuensis. 相似文献