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911.
Megumi Saito Kazuhiro Okumura Ikuo Miura Shigeharu Wakana Ryo Kominami Yuichi Wakabayashi 《Experimental Animals》2014,63(3):339-348
Genome-wide association studies have revealed that many low-penetrance cancer
susceptibility loci are located throughout the genome; however, a very limited number of
genes have been identified so far. Using a forward genetics approach to map such loci in a
mouse skin cancer model, we previously identified strong genetic loci conferring
resistance to chemically induced skin papillomas on chromosome 4 and 7 with a large number
of [(FVB/N × MSM/Ms) F1 × FVB/N] backcross mice. In this report, we describe a
combination of congenic mapping and allele-specific alteration analysis of the loci on
chromosome 4. We used linkage analysis and a congenic mouse strain,
FVB.MSM-Stmm3 to refine the location of Stmm3 (Skin
tumor modifier of MSM 3) locus within a physical interval of about 34 Mb on distal
chromosome 4. In addition, we used patterns of allele-specific imbalances in tumors from
N2 and N10 congenic mice to narrow down further the region of
Stmm3 locus to a physical distance of about 25 Mb. Furthermore,
immunohistochemical analysis showed papillomas from congenic mice had less proliferative
activity. These results suggest that Stmm3 responsible genes may have an
influence on papilloma formation in the two-stage skin carcinogenesis by regulating
papilloma growth rather than development. 相似文献
912.
Kazuhiro Ohara Hideaki Unno Yasuhiro Oshima Miho Hosoya Naoto Fujino Kazutake Hirooka Seiji Takahashi Satoshi Yamashita Masami Kusunoki Toru Nakayama 《The Journal of biological chemistry》2014,289(35):24499-24510
To investigate the mechanism for low pH adaptation by a carboxylesterase, structural and biochemical analyses of EstFa_R (a recombinant, slightly acidophilic carboxylesterase from Ferroplasma acidiphilum) and SshEstI (an alkaliphilic carboxylesterase from Sulfolobus shibatae DSM5389) were performed. Although a previous proteomics study by another group showed that the enzyme purified from F. acidiphilum contained an iron atom, EstFa_R did not bind to iron as analyzed by inductively coupled plasma MS and isothermal titration calorimetry. The crystal structures of EstFa_R and SshEstI were determined at 1.6- and 1.5-Å resolutions, respectively. EstFa_R had a catalytic triad with an extended hydrogen bond network that was not observed in SshEstI. Quadruple mutants of both proteins were created to remove or introduce the extended hydrogen bond network. The mutation on EstFa_R enhanced its catalytic efficiency and gave it an alkaline pH optimum, whereas the mutation on SshEstI resulted in opposite effects (i.e. a decrease in the catalytic efficiency and a downward shift in the optimum pH). Our experimental results suggest that the low pH optimum of EstFa_R activity was a result of the unique extended hydrogen bond network in the catalytic triad and the highly negatively charged surface around the active site. The change in the pH optimum of EstFa_R happened simultaneously with a change in the catalytic efficiency, suggesting that the local flexibility of the active site in EstFa_R could be modified by quadruple mutation. These observations may provide a novel strategy to elucidate the low pH adaptation of serine hydrolases. 相似文献
913.
This study involved mice that received 4 days of ethanol (EtOH) vapor inhalation and then were assessed for type 1 inositol 1,4,5‐trisphosphate receptor (IP3Rs‐1) expression and the development of EtOH‐induced place preference at various time points in withdrawal. IP3R‐1 protein was found to be significantly increased in the nucleus accumbens (NAcc) of mice immediately after 4‐day EtOH vapor inhalation, while it significantly reduced to the control level during the next 3 days of withdrawal from EtOH inhalation. EtOH (2 g/kg, i.p.)‐induced place preference after 3 days of withdrawal from EtOH vapor inhalation increased dose dependently for 4 days, which was significantly inhibited by 2‐aminophenoxyethane‐borate, an antagonist for IP3Rs. EtOH conditioning significantly increased, compared to alcohol‐naïve control mice, both IP3R‐1 protein and the release of dopamine in the NAcc of mice after 3 days of withdrawal from EtOH vapor inhaled for 4 days, and this increase of IP3R‐1 protein was completely abolished by intracerebroventricular injection of FK506, an inhibitor for calcineurin. These results indicate that the sensitization of EtOH‐induced place preference is due to up‐regulated IP3R‐1 via calcineurin‐mediated pathway after enhanced release of dopamine in the NAcc on EtOH administration during EtOH conditioning.
914.
Anu Davaasuren Temuulen Dorjsuren Tetsuya Yanagida Yasuhito Sako Kazuhiro Nakaya Abmed Davaajav Gurbadam Agvaandaram Tsatsral Enkhbat Battsetseg Gonchigoo Nyamkhuu Dulmaa Gantigmaa Chuluunbaatar Akira Ito 《The Korean journal of parasitology》2014,52(2):211-214
Epidemiological situation of taeniasis in Mongolia was assessed based on mitochondrial DNA identification of the parasite species. Multiplex PCR was used on a total of 194 proglottid specimens of Taenia species and copro-PCR and loop-mediated isothermal amplification (LAMP) assays were utilized for detection of copro-DNA of 37 fecal samples from taeniasis patients submitted to the Mongolian National Center for Communicable Diseases (NCCD) from 2002 to 2012. In addition, 4 out of 44 calcified cysts in beef kept in formalin since 2003 were evaluated for histopathological confirmation of cattle cysticercosis. All proglottid specimens and stool samples were confirmed to be Taenia saginata by multiplex PCR and by copro-PCR and LAMP, respectively. Cysts collected from cattle were morphologically confirmed to be metacestodes of Taenia species. T. saginata taeniasis was identified from almost all ages from a 2-year-old boy up to a 88-year-old woman and most prominently in 15-29 age group (37%, 74/198) followed by 30-44 age group (34.8%, 69/198 ) from 15 of Mongolia''s 21 provinces, while cattle cysticerci were found from 12 provinces. The highest proportion of taeniasis patients was in Ulaanbaatar, the capital of Mongolia. 相似文献
915.
Hiroaki Egashira Akira Kuwashima Hiromi Ishiguro Kazuhiro Fukushima Takashi Kaya Shigeru Imanishi 《Acta Physiologiae Plantarum》2000,22(3):324-326
Tomato gray mold (Botrytis cinerea Pers.) is a common disease worldwide, and often causes serious production loss by infecting leaves, stems, flowers and fruits.
Presently, no resistant cultivars are available. To find new breeding materials for gray mold resistance, assessment for resistance
of the leaflet and stem in six tomato cultivars, 44 wild tomato accessions and a Solanum lycopersicoides accession was performed. Although no correlation was observed (r=−0.127ns) between resistance of the leaflet and the stem, L. peruvianum LA2745, L. hirsutum LA2314 and L. pimpinellifolium LA1246 showed high resistance both in the leaflet and in the stem. Particularly, in the leaves of LA2745, no lesions were
observed even more than two weeks after the inoculation with conidia, and F1s between a cultivated tomato and LA2745 also
showed high resistance as observed in LA2745. From these results, LA2745 is thought to be a promising material for breeding
gray-mold resistant cultivars. 相似文献
916.
A mercury removal-recovery system was developed for collection of elemental mercury volatilized by biological mercuric ion reduction. Using the mercury removal-recovery system, removal of mercuric chloride from mercury-containing buffer without nutrients by resting cells of mercury-resistant bacterium, Pseudomonas putida PpY101/pSR134 was tested. Optimum temperature, pH, thiol compounds and cell concentration on removal of mercuric chloride were determined, and 92 to 98% of 40 mg Hg l–1 was recovered in 24 h. The efficiency of mercuric chloride removal from river water and seawater was as high as that observed when using a buffered solution. 相似文献
917.
Apristurus platyrhynchus and four related species were reviewed taxonomically.A. sibogae from Indonesia andA. micropterygeus from the South China Sea were valid species.A. verweyi from the Philippines andA. acanutus from the South China Sea were junior synonyms ofA. platyrhynchus. A. platyrhynchus was re-described, and its new biological information was provided. 相似文献
918.
919.
920.
In vitro phosphorylation of the tumor suppressor gene RB protein by mitosis-specific histone H1 kinase 总被引:19,自引:0,他引:19
Y Taya H Yasuda M Kamijo K Nakaya Y Nakamura Y Ohba S Nishimura 《Biochemical and biophysical research communications》1989,164(1):580-586
The major components of the mitosis-specific histone H1 kinase are CDC2 kinase and cyclin and the consensus amino acid sequence for phosphorylation by this enzyme has been proposed. We have noted the presence of such sequences in six sites of the tumor suppressor gene RB protein and determined whether or not RB protein is in fact phosphorylated by this kinase. Highly purified enzyme was used for this purpose. HeLa cell extracts immunoprecipitated with anti-RB antiserum as well as RB proteins expressed in E. coli cells were shown to be phosphorylated by this kinase in vitro. Synthetic peptides for the six expected sites were also phosphorylated. These results suggest the possibility that the function of RB protein is regulated by CDC2 kinase. 相似文献