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961.
Chizuko Yatome Hiroki Matsufuru Toru Taguchi Toshihiko Ogawa 《Applied microbiology and biotechnology》1993,39(6):778-781
4-Dimethylaminoazobenzene-2-carboxylic acid (DMBC) was utilized as a necessary carbon and nitrogen source by Pseudomonas stutzeri IAM 12097. o-Aminobenzoic acid (o-ABA), N,N-dimethyl-p-phenylenediamine (DMPA) and cathecol were identified as intermediates of DMBC degradation. DMBC was degraded at a concentration below 70 mol dm–3. The ability to utilize DMBC in P. stutzeri was lost spontaneously to some extent. When P. stutzeri was cured of plasmid DNA (approximately 8 MDal) by treatment with mitomycin C, acridine orange, and chloramphenicol, DMBC was not utilized by the resultant strain. These facts suggest that the degradative ability on DMBC in P. stutzeri is controlled by plasmid DNA.
Correspondence to: C. Yatome 相似文献
962.
The regeneration of pioneer tree species under browsing pressure of Sika deer in an evergreen oak forest 总被引:4,自引:0,他引:4
The effects of Sika deer (Cervus nippon) browsing on the regeneration of pioneer species were studied in relation to canopy gaps in a warm temperate evergreen oak
forest in Kasugayama, Nara City. Four study sites, three in canopy gaps and one under a closed canopy, were selected and each
divided into fenced and unfenced plots. Under the closed canopy, seedlings of all the pioneer species died irrespective of
browsing pressure. However, in the canopy gap sites, seedlings of the pioneer species could establish and grow well. The seedling
survival ratio in the fenced plots in the canopy gaps was >60% 1 year after germination. However, in the unfenced plots, only
<20% of the seedlings survived 1 year, with all dying within 3 years after germination. Thus, the regeneration of pioneer
trees in this forest was strongly inhibited by deer browsing. Successful regeneration of a pioneer,Zanthoxylum ailanthoides, occurred for several years even after two major wind disturbances during the past 90 years. This may be due to less browsing
pressure from the deer. 相似文献
963.
964.
965.
Veena Prasad Asish Ray Chaudhuri Matthew Curcio Isao Tomita Fukutaro Mizuhashi Kyoji Murata Richard F. Ludue?a 《Journal of Protein Chemistry》1998,17(7):663-668
Tubulin, the subunit protein of microtubules, undergoes a time-dependent loss of functional properties known as decay. We
have previously shown that the drug 2-(4-fluorophenyl)-1-(2-chloro-3,5-dimethoxyphenyl)-3-methyl-6-phenyl-4(1H)-pyridinone (IKP104) accelerates decay, but that in the presence of colchicine, IKP104 becomes a stabilizer of tubulin. To
see if this is due to conformational effects specific to colchicine or simply to occupancy at the colchicine site, we examined
the effects of nocodazole and podophyllotoxin, two well-known competitive inhibitors of colchicine for binding to tubulin,
on IKP104’s acceleration of decay. We found that podophyllotoxin abolished IKP104’s accelerating effect and, like colchicine,
turned it into a stabilizer of tubulin. Nocodazole’s effects were similar to those of podophyllotoxin and colchicine, in that
it abolished IKP104-induced enhancement of decay; however, in the presence of nocodazole, IKP104 caused little or no stabilization
of tubulin. Since colchicine, nocodazole, and podophyllotoxin have very different interactions with tubulin, but all inhibit
the IKP104-induced enhancement of decay, our findings suggest that this inhibition arises from occupancy of the colchicine
site rather than from a direct conformational effect of these two drugs. 相似文献
966.
Determination of the Nucleotide Sequence of Bombyx mori Cytoplasmic Polyhedrosis Virus Segment 9 and Its Expression in BmN4 Cells 总被引:13,自引:0,他引:13
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Kyoji Hagiwara Masahiro Tomita Kenta Nakai Jun Kobayashi Shigetoshi Miyajima Tetsuro Yoshimura 《Journal of virology》1998,72(7):5762-5768
Cloning and sequencing of segment 9 of Bombyx mori cytoplasmic polyhedrosis virus (BmCPV) strains H and I were performed. The segment consisted of 1,186 bp harboring 5′ and 3′ noncoding regions and an open reading frame from positions 75 to 1037, encoding a protein with 320 amino acids, termed NS5. Comparison of the nucleotide sequences of NS5 for the two strains indicated 37 point differences resulting in only six amino acid replacements. Homology search showed that NS5 has localized similarities to human poliovirus RNA-dependent RNA polymerase and human rotavirus NS26. By Western blot analysis, NS5 was found in BmCPV-infected midgut cells, but not in polyhedra or virus virions, and was mainly detectable in the nucleus in BmCPV-infected BmN4 cells. Immunoblot analysis with anti-NS5 and antipolyhedrin antibodies displayed marked differences in the period of expression of NS5 and polyhedrin: the polyhedrin molecule was first detected 2 or 3 days after infection with BmCPV, whereas the expression of NS5 was initiated within a few hours. In addition, the level of polyhedrin increased as the infection developed, whereas the amount of NS5 remained essentially constant. When segment 9 was expressed with a baculovirus expression system, the resulting NS5 protein possessed the ability to bind to the double-stranded RNA genome. These results suggest that NS5 is expressed in early stages of infection and contributes to regulation of genomic RNA function. 相似文献
967.
Production and Extracellular Secretion of Aqualysin I (a Thermophilic Subtilisin-Type Protease) in a Host-Vector System for Thermus thermophilus 总被引:1,自引:0,他引:1
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Nami Touhara Hayao Taguchi Yoshinori Koyama Takahisa Ohta Hiroshi Matsuzawa 《Applied microbiology》1991,57(11):3385-3387
Aqualysin I is synthesized as a large precursor, processed, and secreted into the culture medium by Thermus aquaticus YT-1. An expression plasmid for the aqualysin I gene in T. thermophilus HB27 was constructed. T. thermophilus cells harboring the recombinant plasmid produced correctly processed aqualysin I, and the mature enzyme was secreted into the culture medium. 相似文献
968.
K. Sakomoto T. Taguchi 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1991,81(4):509-513
Summary Mesophyll protoplasts of tomato (Lycopersicon esculentum) and pepino (Solanum muricatum) were fused by using an electrofusion method and cultured in modified MS medium supplemented with naphthaleneacetic acid and kinetin, in which only pepino and somatic hybrid protoplasts could divide. Somatic hybrid plants showing intermediate characteristics in morphology were regenerated from the calli exhibiting vigorous growth in contrast with those of pepino. The hybrid nature of these plants was confirmed by cytological observation and biochemical analyses of phosphoglucomutase isozymes and the fraction-1-protein. The regenerated somatic hybrids grew to flowering stage and set fruits. 相似文献
969.
Distributions of 29 vegetation types in China as a function of climatic humidity or aridity were analysed using Thornthwaite's
system, by employing meteorological records from 671 stations in China. The annual potential evapotranspiration and the humidity/aridity
indices were calculated for every station, and distribution maps of water deficiency, water surplus and moisture index (Im)
were constructed. The Im map showed that arid areas (Im<0) occupied about 56% of the country. The effect of the difference
in soil water storage capacity on Thornthwaite's indices was examined, and Im values were found to differ little, although
some differences were observed in actual annual evapotranspiration, water deficiency and water surplus values. Correlations
between Im values and distributions of 29 vegetation types, identified from a vegetation map with a scale of 1/4000000, were
investigated. The distributions of desert, steppe, woodland, deciduous forest and evergreen forest corresponded to Im values
of below −40, −40–−20, −20-0, 0–60 and over 60, respectively. In addition, climatic factors delimiting the northern distribution
of evergreen broadleaf forest were investigated, and it was clarified that the northern limit was restricted by combined hydrothermal
conditions, and not by the low temperature in winter. 相似文献
970.
O Taguchi Y Kikuchi W Hida N Iwase M Satoh T Chonan T Takishima 《Journal of applied physiology》1991,71(6):2183-2190
To determine whether the intensity of dyspnea at a given level of respiratory motor output differs between bronchoconstriction and the presence of an external resistance, we compared the sensation of difficulty in breathing during isocapnic voluntary hyperventilation in six normal subjects. An external resistance of 1.9 cmH2O.1-1.s was applied during both inspiration and expiration. To induce bronchoconstriction, histamine aerosol (5 mg/ml) was inhaled until airway resistance (Raw) increased to a level approximately equal to the subject's control Raw plus the added external resistance. To clarify the role of vagal afferents on the genesis of dyspnea during both forms of obstruction to airflow, the effect of airway anesthesia by lidocaine aerosol inhalation was also examined after histamine and during external resistive loading. The sensation of difficulty in breathing was rated at 30-s intervals on a visual analog scale during isocapnic voluntary hyperpnea, in which the subjects were asked to copy an oscilloscope volume trace obtained previously during progressive hypercapnia. Histamine inhalation significantly increased the intensity of the dyspneic sensation over the equivalent external resistive load at the same levels of ventilation and occlusion pressure during voluntary hyperpnea. Inhaled lidocaine decreased the sensation of dyspnea during bronchoconstriction with no change in Raw, but it did not significantly change the sensation during external resistive loading. These results suggest that afferent vagal activity plays a role in the genesis of dyspnea during bronchoconstriction. 相似文献