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Makoto Suzuki Shin Nishiumi Takashi Kobayashi Takeshi Azuma Masaru Yoshida 《Metabolomics : Official journal of the Metabolomic Society》2016,12(4):68
Introduction
The adenomatous polyposis coli (APC) gene is a tumor suppressor gene that is inactivated in the initiation of colorectal neoplasia. Apc Min/+ mice, which possess a heterozygous APC mutation, develop numerous adenomatous polyps, which are similar to those observed in familial adenomatous polyposis (FAP) in humans. However, unlike FAP patients, Apc Min/+ mice predominantly develop adenomatous polyps in the small intestine. The metabolic changes associated with the development of polyps in the small and large intestine remain to be investigated.Objectives
The objective of this study was to elucidate the metabolic changes associated with intestinal polyp formation.Methods
We compared the metabolite levels of pairs of polyp and non-polyp tissues obtained from the small intestines (n = 12) or large intestines (n = 7) of Apc Min/+ mice. To do this, we analyzed the tissue samples using two methods, liquid chromatography-tandem mass spectrometry (1) with a pentafluorophenylpropyl column for cation analysis, and (2) with a C18 reversed phase column coupled to an ion-pair reagent for anion analysis.Results
Pathway mapping of the metabolites whose levels were significantly altered revealed that the polyp tissue of the small intestine contained significantly higher levels of intermediates involved in glycolysis, the pentose phosphate pathway, nucleotide metabolism, or glutathione biosynthesis than in the equivalent non-polyp tissue. In addition, significantly higher levels of methionine cycle intermediates were detected in the polyp tissues of both the large and small intestines. Organ-dependent (small vs. large intestine) differences were also detected in the levels of most amino acids and urea cycle intermediates.Conclusion
Our results indicate that various metabolic changes are associated with polyp development, and understanding these alterations could make it possible to evaluate the treatment response of colorectal cancer earlier.254.
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Efficient modification of the myostatin gene in porcine somatic cells and generation of knockout piglets
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257.
Jaeho Shin Dong Shin Choi Hyeon Jeong Lee Yousung Jung Jang Wook Choi 《Liver Transplantation》2019,9(14)
Aqueous zinc ion batteries (AZIBs) are steadily gaining attention based on their attractive merits regarding cost and safety. However, there are many obstacles to overcome, especially in terms of finding suitable cathode materials and elucidating their reaction mechanisms. Here, a mixed‐valence vanadium oxide, V6O13, that functions as a stable cathode material in mildly acidic aqueous electrolytes is reported. Paired with a zinc metal anode, this material exhibits performance metrics of 360 mAh g?1 at 0.2 A g?1, 92% capacity retention after 2000 cycles, and 145 mAh g?1 at a current density of 24.0 A g?1. A combination of experiments and density functional theory calculations suggests that hydrated intercalation, where water molecules are cointercalated with Zn ions upon discharge, accounts for the aforementioned electrochemical performance. This intercalation mechanism facilitates Zn ion diffusion throughout the host lattice and electrode–electrolyte interface via electrostatic shielding and concurrent structural stabilization. Through a correlation of experimental data and theoretical calculations, the promise of utilizing hydrated intercalation as a means to achieve high‐performance AZIBs is demonstrated. 相似文献
258.
Shafket Rasool Doan Van Vu Chang Eun Song Hang Ken Lee Sang Kyu Lee Jong‐Cheol Lee Sang‐Jin Moon Won Suk Shin 《Liver Transplantation》2019,9(21)
The room temperature (RT) processability of the photoactive layers in polymer solar cells (PSCs) from halogen‐free solvent along with their highly reproducible power conversion efficiencies (PCEs) and intrinsic thickness tolerance are extremely desirable for the large‐area roll‐to‐roll (R2R) production. However, most of the photoactive materials in PSCs require elevated processing temperatures due to their strong aggregation, which are unfavorable for the industrial R2R manufacturing of PSCs. These limiting factors for the commercialization of PSCs are alleviated by synthesizing random terpolymers with components of (2‐decyltetradecyl)thiophen‐2‐yl)naphtho[1,2‐c:5,6‐c′]bis[1,2,5]thiadiazole and bithiophene substituted with methyl thiophene‐3‐carboxylate (MTC). In contrast to the temperature‐dependent PNTz4T polymer, the resulting random terpolymers (PNTz4T‐MTC) show better solubility, slightly reduced crystallinity and aggregation, and weaker intermolecular interaction, thus enabling PNTz4T‐MTC to be processed at RT from a halogen‐free solvent. Particularly, the PNTz4T‐5MTC‐based photoactive layer exhibits an excellent PCE of 9.66%, which is among the highest reported PCEs for RT and ecofriendly halogen‐free solvent processed fullerene‐based PSCs, and a thickness tolerance with a PCE exceeding 8% from 100 to 520 nm. Finally, large‐area modules fabricated with the PNTz4T and PNTz4T‐5MTC polymer have shown 4.29% and 6.61% PCE respectively, with an area as high as 54.45 cm2 in air. 相似文献
259.
Shin H. Haga J. H. Kosawada T. Kimura K. Li Y. S. Chien S. Schmid-Schönbein G. W. 《Biomechanics and modeling in mechanobiology》2019,18(1):5-16
Biomechanics and Modeling in Mechanobiology - Recent experimental evidence points to the possibility that cell surface-associated caveolae may participate in mechanotransduction. The particular... 相似文献
260.
Fiona C. Lewis‐McDougall Prashant J. Ruchaya Eva Domenjo‐Vila Tze Shin Teoh Larissa Prata Beverley J. Cottle James E. Clark Prakash P. Punjabi Wael Awad Daniele Torella Tamara Tchkonia James L. Kirkland Georgina M. Ellison‐Hughes 《Aging cell》2019,18(3)
Aging leads to increased cellular senescence and is associated with decreased potency of tissue‐specific stem/progenitor cells. Here, we have done an extensive analysis of cardiac progenitor cells (CPCs) isolated from human subjects with cardiovascular disease, aged 32–86 years. In aged subjects (>70 years old), over half of CPCs are senescent (p16INK4A, SA‐β‐gal, DNA damage γH2AX, telomere length, senescence‐associated secretory phenotype [SASP]), unable to replicate, differentiate, regenerate or restore cardiac function following transplantation into the infarcted heart. SASP factors secreted by senescent CPCs renders otherwise healthy CPCs to senescence. Elimination of senescent CPCs using senolytics abrogates the SASP and its debilitative effect in vitro. Global elimination of senescent cells in aged mice (INK‐ATTAC or wild‐type mice treated with D + Q senolytics) in vivo activates resident CPCs and increased the number of small Ki67‐, EdU‐positive cardiomyocytes. Therapeutic approaches that eliminate senescent cells may alleviate cardiac deterioration with aging and restore the regenerative capacity of the heart. 相似文献