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941.
Kenichi Nonaka Hidetoshi Miyazaki Masato Iwatsuki Kazuro Shiomi Hiroshi Tomoda Satoshi ōmura Rokuro Masuma 《Mycoscience》2012,53(4):312-318
Staphylotrichum boninense, a new hyphomycete classified in the Chaetomiaceae (Ascomycota), was isolated from soils in the Bonin Islands, Japan. It is characterized morphologically by the production of yellow-orange colonies and subglobose holoblastic conidia. Morphologically the species is similar to S. coccosporum, but it is significantly different from S. coccosporum in phylogeny and also differs with respect to its secondary metabolite profile. 相似文献
942.
Koilkonda P Sato S Tabata S Shirasawa K Hirakawa H Sakai H Sasamoto S Watanabe A Wada T Kishida Y Tsuruoka H Fujishiro T Yamada M Kohara M Suzuki S Hasegawa M Kiyoshima H Isobe S 《Molecular breeding : new strategies in plant improvement》2012,30(1):125-138
Large-scale development of expressed sequence tag simple sequence repeat (EST-SSR) markers was performed in peanut (Arachis hypogaea L.) to obtain more informative genetic markers. A total of 10,102 potential non-redundant EST sequences, including 3,445 contigs and 6,657 singletons, were generated from cDNA libraries of the gynophore, roots, leaves and seedlings. A total of 3,187 primer pairs were designed on flanking regions of SSRs, some of which allowed one and two base mismatches. Among the 3,187 markers generated, 2,540 (80%) were trinucleotide repeats, 302 (9%) were dinucleotide repeats, and 345 (11%) were tetranucleotide repeats. Pre-polymorphic analyses of 24 Arachis accessions were performed using 10% polyacrylamide gels. A total of 1,571 EST-SSR markers showing clear polymorphisms were selected for further polymorphic analysis with a Fluoro-fragment Analyzer. The 16 Arachis accessions examined included cultivated peanut varieties as well as diploid species with the A or B genome. Altogether 1,281 (81.5%) of the 1,571 markers were polymorphic among the 16 accessions, and 366 (23.3%) were polymorphic among the 12 cultivated varieties. Diversity analysis was performed and the genotypes of all 16 Arachis accessions showed similarity coefficients ranging from 0.37 to 0.97. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11032-011-9604-8) contains supplementary material, which is available to authorized users. 相似文献
943.
944.
Autophagy is a bulk degradation system in all eukaryotic cells and regulates a variety of biological activities in higher eukaryotes. Recently involvement of autophagy in the regulation of the secretory pathway has also been reported, but the molecular mechanism linking autophagy with the secretory pathway remains largely unknown. Here we show that Atg16L1, an essential protein for canonical autophagy, is localized on hormone-containing dense-core vesicles in neuroendocrine PC12 cells and that knockdown of Atg16L1 causes a dramatic reduction in the level of hormone secretion independently of autophagic activity. We also find that Atg16L1 interacts with the small GTPase Rab33A and that this interaction is required for the dense-core vesicle localization of Atg16L1 in PC12 cells. Our findings indicate that Atg16L1 regulates not only autophagy in all cell types, but also secretion from dense-core vesicles, presumably by acting as a Rab33A effector, in particular cell types. 相似文献
945.
Takahashi A Imai Y Yamakoshi K Kuninaka S Ohtani N Yoshimoto S Hori S Tachibana M Anderton E Takeuchi T Shinkai Y Peters G Saya H Hara E 《Molecular cell》2012,45(1):123-131
Both the DNA damage response (DDR) and epigenetic mechanisms play key roles in the implementation of senescent phenotypes, but very little is known about how these two mechanisms are integrated to establish senescence-associated gene expression. Here we show that, in senescent cells, the DDR induces proteasomal degradation of G9a and GLP, major histone H3K9 mono- and dimethyltransferases, through Cdc14B- and p21(Waf1/Cip1)-dependent activation of APC/C(Cdh1) ubiquitin ligase, thereby causing a global decrease in H3K9 dimethylation, an epigenetic mark for euchromatic gene silencing. Interestingly, induction of IL-6 and IL-8, major players of the senescence-associated secretory phenotype (SASP), correlated with a decline of H3K9 dimethylation around the respective gene promoters and knockdown of Cdh1 abolished IL-6/IL-8 expression in senescent cells, suggesting that the APC/C(Cdh1)-G9a/GLP axis plays crucial roles in aspects of senescent phenotype. These findings establish a role for APC/C(Cdh1) and reveal how the DDR integrates with epigenetic processes to induce senescence-associated gene expression. 相似文献
946.
Tokumura A Taira S Kikuchi M Tsutsumi T Shimizu Y Watsky MA 《Prostaglandins & other lipid mediators》2012,97(3-4):83-89
We previously found that lysophosphatidic acid (LPA)-like activity eliciting Cl(-) currents in Xenopus oocytes is increased in rabbit aqueous humor (AH) following corneal freeze wounds. The purpose of this study was to examine whether actual levels of LPA in AH from wounded eyes are higher than those from control eyes, and to determine the sources and enzymatic pathways of AH LPA in control and wounded conditions. Lysophospholipase D (lysoPLD) activity was measured by the enzymatic determination of choline following incubation of AH samples with exogenous lysophosphatidylcholines (LPCs). The molecular species compositions of LPA and LPC in fresh and incubated AH were determined by liquid chromatography-tandem mass spectrometry. A high, but similar activity of lysoPLD in the samples from both control and freeze-wounded eyes was detected. Its enzymatic properties resemble those of plasma lysoPLD, identified as autotaxin. Levels of LPCs, predominant substrates of lysoPLD in AH, were several times higher in the AH samples from injured eyes than those from the control eyes. Our results suggest that lysoPLD is constitutively released from corneal tissues and/or ciliary body into the AH, with no injury-induced increase in release following freeze-wounding. They also suggest that wound-induced increases in LPA-like biological activity are due to linoleoyl species-rich molecular composition in AH from wounded eyes. A possible mechanism of the altered molecular composition is an increase in the AH concentrations of LPCs, linoleoyl species of which are preferentially converted to corresponding unsaturated LPA by the constitutively active lysoPLD. 相似文献
947.
This paper reports an experimental study of the formation of a mixed O3+ O2+ CO2 hydrate and its frozen storage under atmospheric pressure, which aimed to establish a hydrate-based technology for preserving ozone (O3), a chemically unstable substance, for various industrial, medical and consumer uses. By improving the experimental technique that we recently devised for forming an O3+ O2+ CO2 hydrate, we succeeded in significantly increasing the fraction of ozone contained in the hydrate. For a hydrate formed at a system pressure of 3.0 MPa, the mass fraction of ozone was initially about 0.9%; and even after a 20-day storage at −25°C and atmospheric pressure, it was still about 0.6%. These results support the prospect of establishing an economical, safe, and easy-to-handle ozone-preservation technology of practical use. 相似文献
948.
Background
Many patients with chronic kidney disease (CKD) suffer from fatigue caused by anemia, but that anemia can be reversed. Successful treatment can be measured as a decrease in fatigue and an increase in energy or vitality, particularly on the vitality (VT) subscale of the SF-36. Changes in VT scores are most commonly interpreted in terms of minimally important differences or standardized effect sizes, but neither a minimally important difference nor a standardized effect size provides information about how patients’ activities are affected. Therefore, we analyzed the association between differences in VT scores and a variable that is meaningful to patients and to society the frequency of going out.Study Design
Questionnaire survey. Analyses of differences among participants at bseline, and analyses of differences within participants over time.Setting and Participants
CKD patients who were not on dialysis and were involved in a study of anti-anemia therapy.Predictor
VT scores.Outcome
Frequency of going out.Measurements
VT scores and the frequency of going out.Results
At baseline, higher VT scores and younger age were associated with going out more often, while sex and the presence of diabetic nephropathy were not associated with the frequency of going out. Greater changes in VT scores over time were associated with greater changes in the frequency of going out, in univariate and multivariate analyses.Conclusions
At baseline, VT was associated with the frequency of going out. Increases in VT were also associated with increases in the frequency of going out. These results show how VT scores can be linked to daily activities that are important to individual patients and to society. 相似文献949.
Colostomy is conventionally the only treatment for anal dysfunction. Recently, a few trials of anorectal transplantation in animals have been published; however, further development of this technique is required. Moreover, it is crucial to perform this research in dogs, which resemble humans in anorectal anatomy and biology. We designed a canine anorectal transplantation model, wherein anorectal autotransplantation was performed by anastomoses of the rectum, inferior mesenteric artery (IMA) and vein, and pudendal nerves. Resting pressure in the anal canal and anal canal pressure fluctuation were measured before and after surgery. Graft pathology was examined three days after surgery. The anal blood supply was compared with that in three beagles using indocyanine green (ICG) fluorescence angiography. The anorectal graft had sufficient arterial blood supply from the IMA; however, the graft's distal end was congested and necrotized. Functional examination demonstrated reduced resting pressure and the appearance of an irregular anal canal pressure wave after surgery. ICG angiography showed that the pudendal arteries provided more blood flow than the IMA to the anal segment. This is the first canine model of preliminary anorectal autotransplantation, and it demonstrates the possibility of establishing a transplantation model in dogs using appropriate vascular anastomoses, thus contributing to the progress of anorectal transplantation. 相似文献
950.
Albino and hooded (or piebald) rats are one of the most frequently used laboratory animals for the past 150 years. Despite this fact, the origin of the albino mutation as well as the genetic basis of the hooded phenotype remained unclear. Recently, the albino mutation has been identified as the Arg299His missense mutation in the Tyrosinase gene and the hooded (H) locus has been mapped to the ~460-kb region in which only the Kit gene exists. Here, we surveyed 172 laboratory rat strains for the albino mutation and the hooded (h) mutation that we identified by positional cloning approach to investigate possible genetic roots and relationships of albino and hooded rats. All of 117 existing laboratory albino rats shared the same albino missense mutation, indicating they had only one single ancestor. Genetic fine mapping followed by de novo sequencing of BAC inserts covering the H locus revealed that an endogenous retrovirus (ERV) element was inserted into the first intron of the Kit gene where the hooded allele maps. A solitary long terminal repeat (LTR) was found at the same position to the ERV insertion in another allele of the H locus, which causes the so called Irish (h(i)) phenotype. The ERV and the solitary LTR insertions were completely associated with the hooded and Irish coat patterns, respectively, across all colored rat strains examined. Interestingly, all 117 albino rat strains shared the ERV insertion without any exception, which strongly suggests that the albino mutation had originally occurred in hooded rats. 相似文献