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21.
A novel enzymatic ligand binding assay for biotin and its benzodiazepine conjugate is based on their binding to horseradish peroxidase-avidin conjugate (A-P) followed by the uptake of biotin-unsaturated A-P onto polystyrene beads coated with biotin-BSA. The detection limit is 1.3 x 10(-16) mol per tube (300 microL) with a 3.3 x 10(-12) M A-P solution and varies with the conjugate concentration employed. The coefficient of variation for 10 repetitive assays of 10(-15) mol of biotin is 6.22%. 相似文献
22.
Shigenori Goto Sumitaka Sakai Jiro Kera Yukie Suma Gen-Ichiro Soma Shoshichi Takeuchi 《Cancer immunology, immunotherapy : CII》1996,42(4):255-261
Lipopolysaccharide (LPS) has been recognized as a potent antitumor agent in animal tumor models; however, its use in human
cancer therapy has been limited to only one trial, in which LPS from Salmonella was given intravenously. It was not very successful because of poor tumor response and was also toxic. We originally developed
LPS prepared from Pantoea agglomerans (LPSp), and this was a well-purified, small-molecular-mass (5 kDa) agent. We chose intradermal rather than intravenous administration
in the hope that the former would release LPS slowly into the bloodstream, and thus be less toxic while preserving antitumor
activity. In our animal tumor models, intradermal administration was indeed less toxic and more beneficial for tumor regression
than intravenous administration. We made a pilot study with intradermal administration of LPSp on the treatment of ten advanced
cancer patients. Five of them had evaluable tumor, which had failed earlier to respond to conventional chemotherapy. Cyclophosphamide
was also administered in this trial, in anticipation of its synergistic effect with LPSp. In this study LPSp was injected
intradermally into each patient twice a week, starting with an initial dose of 0.4 ng/kg, and raising it to 600 or 1800 ng/kg.
A 400-mg/m2 dose of cyclophosphamide was given intravenously every 2 weeks. After completion of the dose escalation, the treatment was
continued for at least 4 months, and it was found that 1800 ng/kg LPSp was well tolerated. A significant level of cytokines
was observed in the sera for at least 8 h. These results indicate higher tolerable doses and remarkably more continuous induction
of the cytokines than were reported in a previous study by others using intravenous administration. Three of the five evaluable
tumors showed a significant response to our combined therapy. Intradermally administered, LPS was less toxic and elicited
a tumor response in combination with cyclophosphamide; it can thus can be applied to cancer treatment even in humans.
Received: 3 August 1995 / Accepted: 2 April 1996 相似文献
23.
Takeuchi Yuichi; Murakami Mina; Nakajima Nobuyoshi; Kondo Noriaki; Nikaido Osamu 《Plant & cell physiology》1996,37(2):181-187
Photoinduced lesions in DNA, namely, cyclobutane pyrimidinedimers (CPDs) and pyrimidine-(6-4)-pyrimidone photoproducts[(6-4)photoproducts], in cucumber cotyledons that had been irradiatedwith naturally occurring levels of UV-B (290320 nm) werequantitated by enzyme-linked immunosorbent assays with monoclonalantibodies specific to each type of photolesion. Induction ofthese photolesions was dependent on temperature and their extentwas reduced by simultaneous irradiation with white light. Thedark repair of both types of photolesion was undetectable. Light-dependentremoval of (6-4)photoproducts was very slow, with 50% removalin 4 h. By contrast, 50% of initial CPDs were removed within15 min. Both photorepair processes were dependent on the intensityof white light and were sensitive to temperature. These resultsindicate that high photolyase activity is present in cucumbercotyledons and that repair activities in cucumber cotyledonsare different from those reported in Arabidopsis, in which (6-4)photoproductsare photorepaired more rapidly than CPDs. (Received October 13, 1995; Accepted December 28, 1995) 相似文献
24.
Fission yeast cut3 and cut14, members of a ubiquitous protein family, are required for chromosome condensation and segregation in mitosis. 总被引:22,自引:1,他引:21 下载免费PDF全文
Y Saka T Sutani Y Yamashita S Saitoh M Takeuchi Y Nakaseko M Yanagida 《The EMBO journal》1994,13(20):4938-4952
Fission yeast temperature-sensitive mutants cut3-477 and cut14-208 fail to condense chromosomes but small portions of the chromosomes can separate along the spindle during mitosis, producing phi-shaped chromosomes. Septation and cell division occur in the absence of normal nuclear division, causing the cut phenotype. Fluorescence in situ hybridization demonstrated that the contraction of the chromosome arm during mitosis was defective. Mutant chromosomes are apparently not rigid enough to be transported poleward by the spindle. Loss of the cut3 protein by gene disruption fails to maintain the nuclear chromatin architecture even in interphase. Both cut3 and cut14 proteins contain a putative nucleoside triphosphate (NTP)-binding domain and belong to the same ubiquitous protein family which includes the budding yeast Smc1 protein. The cut3 mutant was suppressed by an increase in the cut14+ gene dosage. The cut3 protein, having the highest similarity to the mouse protein, is localized in the nucleus throughout the cell cycle. Plasmids carrying the DNA topoisomerase I gene partly suppressed the temperature sensitive phenotype of cut3-477, suggesting that the cut3 protein might be involved in chromosome DNA topology. 相似文献
25.
Yoshihito Suzuki Noboru Murofushi Yun-Hui Zhang Yasutomo Takeuchi 《Journal of Plant Growth Regulation》1994,13(2):63-67
Endogenous gibberellins were analyzed from a parasitic plant, clover broomrape (Orobanche minor Smith), and its host, clover (Trifolium repens L.). Members of both the early-13- and the early-non-hydroxylation pathways were identified from both the parasite and the host (GA12, GA24, GA9 GA4, GA44, GA19, GA20, and GA1 from clover broomrape; GA9, GA4, GA44, GA19, GA20, and GA1 from clover). Quantitative analyses showed that GA44 was present at high levels in both host and parasite. The similarity in the gibberellins suggests the possibility that the major gibberellins in clover broomrape are transported from clover. However gibberellins such as GA58, GA38, and notably GA47 which was identified from a plant for the first time were detected only from clover broomrape, suggesting that the parasite may have the ability to produce at least those gibberellins 相似文献
26.
Kawarabayasi Yutaka; Tanaka Ayako; Ohara Osamu; Arakawa Taku; Oka Masanori; Kato Hisako; Morita Miyo; Fujisawa Hisao 《DNA research》1994,1(6):289-296
To sequence a DNA segment inserted into a cosmid vector underthe directed sequencing strategy, we established a simple andrapid method for generating nested deletions which uses thein vitro packaging system of bacteriophage T3 DNA. The principleis based on the previous finding that this system can translocateany linear double-stranded DNA up to 40 kb into the phage capsidin a time-dependent manner and the encapsulated DNA becomesDNase-resistant. For this purpose, we constructed a cosmid vectorthat carries two different antibiotic selection markers at bothsides of the multiple cloning site, and after insertion of aDNA segment, the clone was linearized by -terminase at the cossite. After the packaging reaction in vitro followed by DNasetreatment, the encapsulated DNA was introduced into Escherichiacoli cells to give clones with unidirectional deletions by differentialantibiotic selection. Restriction and sequence analyses of deletionclones demonstrated that an ordered set of clones with nesteddeletions, ranging from less than 1 kb to 25 kb, was createdfrom either the end of the DNA segment. Thus, nested deletionclones that cover the entire region of a 40-kb cosmid insertcan be obtained by a single packaging reaction, and its restrictionmap can be simultaneously obtained. 相似文献
27.
28.
Marwa Said El-Desoky Rino Takeuchi Hidekazu Katayama Naoaki Tsutsui 《Journal of peptide science》2023,29(12):e3529
The insulin superfamily comprises a group of peptides with diverse physiological functions and is conserved across the animal kingdom. Insulin-like peptides (ILPs) of crustaceans are classified into four major types: insulin, relaxin, gonadulin, and androgenic gland hormone (AGH)/insulin-like androgenic gland factor (IAG). Of these, the physiological functions of AGH/IAG have been clarified to be the regulation of male sex differentiation, but those of the other types have not been uncovered. In this study, we chemically synthesized Maj-ILP1, an ILP identified in the ovary of the kuruma prawn Marsupenaeus japonicus, using a combination of solid-phase peptide synthesis and regioselective disulfide bond formation reactions. As the circular dichroism spectral pattern of synthetic Maj-ILP1 is typical of other ILPs reported thus far, the synthetic peptide likely possessed the proper conformation. Functional analysis using ex vivo tissue incubation revealed that Maj-ILP1 significantly increased the expression of the yolk protein genes Maj-Vg1 and Maj-Vg2 in the hepatopancreas and Maj-Vg1 in the ovary of adolescent prawns. This is the first report on the synthesis of a crustacean ILP other than IAGs and also shows the positive relationship between the reproductive process and female-dominant ILP. 相似文献
29.
Łukasz Wejnerowski Ewa Poniecka Jakub Buda Piotr Klimaszyk Agnieszka Piasecka Marcin Krzysztof Dziuba Gianmarco Mugnai Nozomu Takeuchi Krzysztof Zawierucha 《Journal of phycology》2023,59(5):939-949
Cryoconite, the dark sediment on the surface of glaciers, often aggregates into oval or irregular granules serving as biogeochemical factories. They reduce a glacier's albedo, act as biodiversity hotspots by supporting aerobic and anaerobic microbial communities, constitute one of the organic matter (OM) sources on glaciers, and are a feeder for micrometazoans. Although cryoconite granules have multiple roles on glaciers, their formation is poorly understood. Cyanobacteria are ubiquitous and abundant engineers of cryoconite hole ecosystems. This study tested whether cyanobacteria may be responsible for cryoconite granulation as a sole biotic element. Incubation of Greenlandic, Svalbard, and Scandinavian cyanobacteria in different nutrient availabilities and substrata for growth (distilled water alone and water with quartz powder, furnaced cryoconite without OM, or powdered rocks from glacial catchment) revealed that cyanobacteria bind mineral particles into granules. The structures formed in the experiment resembled those commonly observed in natural cryoconite holes: they contained numerous cyanobacterial filaments protruding from aggregated mineral particles. Moreover, all examined strains were confirmed to produce extracellular polymeric substances (EPS), which suggests that cryoconite granulation is most likely due to EPS secretion by gliding cyanobacteria. In the presence of water as the only substrate for growth, cyanobacteria formed mostly carpet-like mats. Our data empirically prove that EPS-producing oscillatorialean cyanobacteria isolated from the diverse community of cryoconite microorganisms can form granules from mineral substrate and that the presence of the mineral substrate increases the probability of the formation of these important and complex biogeochemical microstructures on glaciers. 相似文献
30.
Watanabe Masao; Nou Ill Sup; Takayama Seiji; Yamakawa Seiyei; Isogai Akira; Suzuki Akinori; Takeuchi Takuji; Hinata Kokichi 《Plant & cell physiology》1992,33(4):343-351
The stigma of Brassica species contain NS-glycoproteins thatexhibit a high degree of structural homology to the S-glycoproteinsof self-incompatibility. Inheritance of and variations in theNS-glycoprotein were studied with reference to self-incompatibility.The detection of NS-glycoproteins was performed by cross-reactionwith an antiserum raised against a purified NS-glycoprotein.In B. campestris, four isoforms of the NS-glycoprotein weredifferentiated by their pI values, but their molecular weightswere identical to one another. The genes for these isoformsof NS-glycoprotein were controlled by alleles at a single locus,tentatively named the NS allele, which was independent of Salleles at both the protein and the DNA level. Segregation ofF2 plants with respect to the self-incompatibility behaviorof pollen tubes can be explained by the S allele model, butit appears not to be affected by the NS alleles. NS-glycoproteinswere found in all 21 species of Brassica and its allies examinedto date. The pI values of these glycoproteins varied among differentspecies. In addition to the isoforms of the NS alleles, maturestigmas contained other groups of proteins that reacted weaklywith the antiserum against the NS-glycoprotein. (Received July 30, 1991; Accepted February 21, 1992) 相似文献