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941.
Matsuda S Niidome T Nonaka H Goto Y Fujimura K Kato M Nakanishi M Akaike A Kihara T Sugimoto H 《Biochemical and biophysical research communications》2008,368(4):971-976
Microglia are believed to play an important role in the regulation of phagocytosis, neuronal survival, neuronal cell death, and inflammation. Recent studies have demonstrated that microglia are multipotential stem cells that give rise to neurons, astrocytes, and oligodendrocytes. However, the functional properties of neurons derived from microglia are poorly understood. In this study, we investigated the possibility that microglia differentiate into functional neurons. Immunocytochemical study demonstrated that microtubule-associated protein 2 (MAP2)-positive cells were derived from microglia under differentiation conditions. Intracellular Ca2+ imaging study demonstrated that KCl caused no significant changes in [Ca2+]i in microglia, whereas it caused a remarkable increase in [Ca2+]i in microglia-derived cells. Furthermore, electrophysiological study demonstrated that the spike waveform, firing rate, and tetrodotoxin sensitivity of extracellular action potentials evoked by 4-aminopyridine from microglia-derived MAP2-positive cells were nearly identical to those from cultured cortical neurons. These results suggest that microglia-derived MAP2-positive cells possess properties of functional neurons. 相似文献
942.
Effects of experimental warming on shoot developmental growth and biomass production were preliminarily investigated in two evergreen dwarf shrubs Empetrum nigrum and Loiseleuria procumbens, using the International Tundra Experiments open-top chamber (OTC) method, in the Tateyama Range, central Japan. An OTC was installed over shrub (E. nigrum and L. procumbens) -dominated vegetation and over shrub-forb (such as Anemone narcissiflora var. nipponica and Solidago virga-aurea ssp. leiocarpa) mixed vegetation, and stem samples of the evergreen shrubs were obtained at 26 months after installing the OTC. The OTC increased the daily mean temperature by 0.1°C to 1.8°C, on average, during the growing season. Shoot developmental growth and biomass production were considerably different between species of different vegetation types. The boreal species E. nigrum generally showed better growth inside the OTC than the arctic and subarctic species L. procumbens. Both species showed significantly larger shoot elongation and biomass production inside the OTC over shrub-dominated vegetation, whereas smaller or reduced growth was detected inside the OTC over shrub-forb mixed vegetation. The variations of growth responses to warming between species of different vegetation types are discussed, especially in relation to interspecific competition under a simulated environmental change. 相似文献
943.
Teramoto K Kontani K Fujita T Ozaki Y Sawai S Tezuka N Fujino S Itoh Y Taguchi O Kannagi R Ogasawara K 《Cancer immunology, immunotherapy : CII》2007,56(3):331-342
We reported previously that pigeon cytochrome c-derived peptides (Pan-IA), which bind broad ranges of MHC class II molecules efficiently, activate T helper (Th) function in mice. In an experimental model, Pan-IA DNA vaccines augmented antitumor immunity in tumor antigen-immunized mice. To elicit more potent antitumor immunity and to eradicate tumors in a therapeutic setting, Pan-IA-loaded dendritic cells (DCs) were inoculated in combination with vaccines including ovalbumin (OVA) antigen DNA in tumor-bearing mice. Seventy percent of the immunized mice survived tumor-free for at least 4 months after treatment. In contrast, mice vaccinated with OVA DNA, either with or without naïve DCs, did not eliminate the tumors and died within 5 weeks. Only in mice vaccinated with OVA DNA and Pan-IA-loaded DCs were both cytotoxic and helper responses specific for OVA induced at the spleen and tumor sites as well as at the vaccination sites. Furthermore, accumulation of OVA-specific CD4+ and CD8+ T lymphocytes and interferon-gamma-mediated anti-angiogenesis were observed in the tumors of these mice. Thus, the combined vaccination primed both tumor-specific cytotoxicity and helper immunity resulting in augmented tumor lysis ability and anti-angiogenic effects. This is the first report to show that most established tumors were successfully eradicated by collaboration of potent antitumor immunity and anti-angiogenic effects by vaccination with tumor antigens and helper-activating analogs. This novel vaccination strategy is broadly applicable, regardless of identifying helper epitopes in target molecules, and contributes to the development of therapeutic cancer vaccines. 相似文献
944.
Dae Keun Kim Kyo Chul Koo Ali Abdel Raheem Ki Hong Kim Byung Ha Chung Young Deuk Choi Koon Ho Rha 《PloS one》2016,11(3)
Purpose/Objectives
To investigate pN1 prostate cancer (PCa) patients treated surgically without immediate adjuvant treatment.Materials and Methods
We analyzed the database of 2316 patients at our institution who underwent robot-assisted radical prostatectomy (RARP)/radical prostatectomy (RP) between July 2005 and November 2012. 87 patients with pN1 PCa and received no neoadjuvant and immediate adjuvant therapy were included in the study. Included pN1 PCa patients were followed up for median of 60 months. Biochemical recurrence (BCR)-free survival, metastasis-free survival (MFS), cancer specific survival (CSS), and overall survival (OS) rates were determined by using Kaplan-Meier analysis. Cox regression analysis was performed to investigate the impact of prostate-specific antigen (PSA) level, Gleason score, extraprostatic extension, seminal vesicle invasion, perineural invasion, lymphovascular invasion, positive surgical margin, tumor volume, early post-operative PSA(6 weeks), PSA nadir, lymph node yield, and number of pathologically positive lymph nodes on survival.Results
The 5-year OS rate of patients was 86.1%, while the CSS rate was 89.6%. The metastasis-free and BCR-free survival rates were 71% and 19.1%, respectively, and each was significantly correlated with the number of positive lymph nodes on log rank tests (p = 0.004 and p = 0.039, respectively). The presence of 2 or more pathologically positive LNs (HR:2.20; 95% CI 1.30–3.72; p = 0.003) and a Gleason score ≥8 (HR: 2.40;95% CI: 1.32–4.38; p = 0.04) were significant negative predictors of BCR free survival on multivariable regression analysis. Furthermore, the presence of 2 or more positive lymph nodes (HR: 1.06; 95% CI 1.01–1.11; p = 0.029) were significant negative predictors of metastasis-free survival on multivariable regression analysis. Additionally, in the patients who had no BCR without adjuvant treatment 9 patients out of 10 (90%) had single positive LN and 5 patients out of 10 (50%) had Gleason score 7. Therefore, single positive LN, and Gleason scores ≤7 have significantly low risk of disease progression.Conclusions
pN1 PCa patients have heterogenous clinical courses. Patients with single positive LN, and Gleason scores ≤7 have low risk of recurrence. Close observation with delayed adjuvant hormone therapy can be considered in these patients. 相似文献945.
A variety of alpha,beta-unsaturated ketones were evaluated for their effect on the jack bean urease. Of 35 compounds tested, 2-cyclohepten-1-one (1), 2-cyclohexen-1-one (2), 2-cyclopenten-1-one (3), and 5,6-dihydro-2H-pyran-2-one (4) showed potent inhibitory activities against the enzyme. The most potent compound (1) (IC50=0.16 mM) showed similar inhibitory potency to hydroxyurea (IC50=0.095 mM). The inhibitory effects of 1, 2, 3, and 4 were significantly reduced by 2-mercaptoethanol or dithiothreitol. These data suggest that alpha,beta-unsaturated ketones inhibited the urease activity, possibly by a Michael-like addition of a protein SH group to the double bond of the alpha,beta-unsaturated carbonyl group. 相似文献
946.
Takeshi Shimoda Takayuki Mitsunaga Masayoshi Uefune Junichiro Abe Soichi Kugimiya Koukichi Nagasaka Kota Sano Satoru Urano Yoshito Suzuki Eizi Yano Junji Takabayashi 《BioControl》2014,59(6):681-688
The limited availability of sugar sources (e.g., flowers) in greenhouses may affect biological pest control by parasitoid wasps. However, few studies have focused on feeding devices to provide parasitoids with sugar foods. We investigated the accessibility of a yellow-colored bottle-type feeding device to adult Cotesia vestalis (Halliday), a larval endoparasitoid of the diamondback moth Plutella xylostella (L.). All parasitoids died within four days in a room with no sugar source, whereas 66.7 % of individuals survived if a bottle-type feeding device providing honey solution was installed. We also investigated female longevity in response to different sugar solutions presented in a bottle-type feeding device. Honey and sugar mixtures (glucose and fructose) improved female longevity (38.4 and 39.2 days, respectively) much more than water (3.1 days), indicating these feeding devices containing sugar foods to be potentially useful for maintaining C. vestalis in greenhouses where natural food sources are limited. 相似文献
947.
Kazunari Higa Naoko Kato Satoru Yoshida Yoko Ogawa Jun Shimazaki Kazuo Tsubota Shigeto Shimmura 《Stem cell research》2013,10(2):147-155
Stem cells have a specialized microenvironment for maintaining self-renewal and multipotent capacities. It is believed that a cornea epithelial stem cell niche exists in the limbus. To characterize the niche of limbal epithelial stem cells, we observed the limbal basal epithelial layer by histological analysis.Cell clusters or cell suspensions from limbal tissue were prepared with collagenase or dispase II and fixed for cytospin sections. Adhesion assays were done to quantitate calcium-dependent cell adhesion. Limbal tissue and cytospin sections were analyzed by immunohistochemistry, transmission electron microscopy and confocal microscopy.AQP1 positive (AQP1+) cells were observed as non-epithelial cells in the subepithelial stroma. AQP1 expression did not co-localize with CD31, podoplanin, MART-1 positive cells, but were observed in vimentin positive stromal cells. When we made a thorough search of limbal basal cells by confocal microscopy, AQP1+ were observed in the proximity of N-cad, K15 and p63 positive limbal basal epithelial cells. Furthermore, electron microscope revealed stromal cells penetrating the epithelial basal membrane and forming calcium-dependent cellular adhesions with N-cad+ limbal basal epithelial cells.Although we could not clearly detect the expression of N-cad in the AQP1+ cells, AQP1+ cells immediately beneath the epithelial basement membrane may be stromal niche-like cells that directly interact with N-cad+ limbal basal epithelial progenitor cells. 相似文献
948.
Identification of a putative vacuolar serine protease gene in the rice blast fungus,Magnaporthe grisea 总被引:1,自引:0,他引:1
Fukiya S Kuge T Tanishima T Sone T Kamakura T Yamaguchi I Tomita F 《Bioscience, biotechnology, and biochemistry》2002,66(3):663-666
We identified and cloned a gene designated SPM1, encoding a serine protease from the rice blast fungus Magnaporthe grisea. SPM1 is a single-copy gene, encoding a subtilisin-like serine protease with 536 amino acids. Analyses of the deduced amino acid sequence of SPM1 suggested that SPM1 would be localized in a vacuole, an important organelle in pathogenicity. 相似文献
949.
950.
Distribution of marine birnavirus (MABV) in marine organisms from Okinawa,Japan, and a unique sequence variation of the VP2/NS region 总被引:1,自引:0,他引:1
Manami Inaba Satoru Suzuki Shin-Ichi Kitamura Norichika Kumazawa Hiroshi Kodama 《Journal of microbiology (Seoul, Korea)》2009,47(1):76-84
Distribution of marine type of Aquabirnavirus (MABV) was examined in shellfish and fish from Okinawa and Ishigaki Islands,
Japan, where water temperature is higher than 25°C through the year. Genome detection and virus isolation were performed for
shellfish and fish samples, and the results revealed the prevalent distribution of MABV in diverse species in the area, although
isolation was not frequently. Detection rate of MABV genome in bivalves was higher than gastropods, which was similar result
to former report in mainland of Japan. Furthermore, the unique five-nucleotide deletion was found with a high rate of occurrence
in the MABV genome from shellfish and fish. This study showed distribution status of MABV in organisms in subtropical waters
by wide monitoring, and discovered new genome variation in VP2/NS region of this virus. 相似文献