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121.
Wang B Feng WY Wang M Shi JW Zhang F Ouyang H Zhao YL Chai ZF Huang YY Xie YN Wang HF Wang J 《Biological trace element research》2007,118(3):233-243
It has been demonstrated that inhaled fine (d < 2.5 μm) and ultrafine (d < 100 nm) particles produce more severe toxicity than coarse particles. Some recent data support the concept that the central
nervous system (CNS) may be a target for the inhaled fine particulates. This work describes initial observation of the transport
of intranasally instilled fine ferric oxide (Fe2O3) particles in animal brain. The iron micro-distribution and chemical state in the mice olfactory bulb and brain stem on day
14 after intranasal instillation of fine Fe2O3 particle (280 ± 80 nm) suspension at a single dose of 40 mg/kg body weight were analyzed by synchrotron radiation x-ray fluorescence
and x-ray absorption near-edge structure (XANES). The micro-distribution map of iron in the olfactory bulb and brain stem
shows an obvious increase of Fe contents in the olfactory nerve and the trigeminus of brain stem, suggesting that Fe2O3 particles were possibly transported via uptake by sensory nerve endings of the olfactory nerve and trigeminus. The XANES
results indicate that the ratios of Fe (III)/Fe (II) were increased in the olfactory bulb and brain stem. The further histopathological
observation showed that the neuron fatty degeneration occurred in the CA3 area of hippocampus. Such results imply an adverse
impact of inhalation of fine Fe2O3 particles on CNS. 相似文献
122.
Huang JC Lei ZL Shi LH Miao YL Yang JW Ouyang YC Sun QY Chen DY 《Biochemical and biophysical research communications》2007,354(1):77-83
Histone modifications are thought to play important roles in various cellular functions. In this article, the distribution patterns of acetylation on histone H4, methylation on histone H3 lysine 9, and phosphorylation on histone H3 serine 10 were examined in in vivo and in vitro fertilization (IVF) preimplantation mouse embryos by using indirect immunofluorescence and scanning confocal microscopy. We desired to know whether the IVF, which has been widely used as a routine assisted reproductive technology in animal and human, was safe at the epigenetic level. As results, we found that there was no difference in these histone modification patterns in in vivo and IVF mouse embryos from zygote to blastocyst stage. Moreover, these histone modifications had different distributions at all examined stages, but they were consistent with the mouse embryo developmental stages. 相似文献
123.
Zhu ZY Jiang MX Yan LY Huang JC Lei ZL Jiang Y Ouyang YC Zhang HX Sun QY Chen DY 《Molecular reproduction and development》2007,74(5):655-663
In this study, somatic cell nuclear transfer (SCNT) and intracytoplasmic sperm injection (ICSI) are used as models of agamogony and syngamy, respectively. In order to elucidate the reasons of low efficiency of somatic cell cloning, cytoskeletal and nuclear organization in cloned mouse embryos was monitored before and during the first cell cycle, and compared with the pattern of ICSI zygote. A metaphase-like spindle with alignment of condensed donor chromosomes was assembled within 3 hr after NT, followed by formation of pronuclear-like structures at 3-6 hr after activation, indicating that somatic nuclear remodeling depends on microtubular network organization. The percentage of two (pseudo-) pronuclei in cloned embryos derived from delayed activation was greater than that in immediate activation group (68.5% vs. 30.8%, P<0.01), but similar to that of ICSI group (68.5% vs. 65.5%, P>0.05). The 2-cell rate in NT embryos was significantly lower than that in zygotes produced by ICSI (64.8% vs. 82.5%, P<0.01). Further studies testified that the cloned embryos reached the metaphase of the first mitosis 10 hr after activation, whereas this occurred at 18 hr in the ICSI zygotes. Comparision of the pattern of microfilament assembly in early NT embryos with that in syngamic zygotes suggested that abnormal microfilamental pattern in cloned embryos may threaten subsequent embryonic development. In conclusion, agamogony, in contrast to syngamy, displays some unique features in respect of cytoskeletal organization, the most remarkable of which is that the first cell cycle is initiated ahead distinctly, which probably leads to incomplete organization of the first mitotic spindle, and contributes to low efficiency of cloning. 相似文献
124.
Nan CL Ouyang YC Zhao ZJ Jiang Y Lei ZL Huang JC Song XF Sun QY Chen DY 《Molecular reproduction and development》2007,74(9):1072-1080
This study attempted to investigate the time course of meiotic progression after transferring primary spermatocyte (PS) into ooplasm at different maturing stages. In present experiments, PSs were introduced into maturing ooplasts or oocytes by electrofusion. Higher fusion rate was obtained by phytohemagglutinin (PHA) agglutination than by perivitelline space (PVS) insertion. When the ooplasms prepared at 0, 2, 5, and 8.5 hr of in vitro maturation (IVM) were used as recipients and PSs were used as donors, the reconstructed cells extruded the first polar body (PB1) approximately 8.5, 7, 5.5, and 3 hr after electrofusion, respectively. Especially, when ooplasm cultured for 8.5 hr in vitro after GV removal was fused with PS, the PB1 was emitted 7-11 hr after electrofusion. Additionally, the PB1 extrusions of GV and pro-MI oocytes fertilized with PSs were 2.5 hr earlier than control oocytes. The results suggest that (1) PSs undergo the first meiosis in different time courses when introduced into ooplasm at different maturing stages; (2) GV material plays an important role in determining the timing of PB1 extrusion; and (3) first meiotic division of GV and pro-MI oocytes can be accelerated by introducing PS. 相似文献
125.
Anti-proliferation and apoptosis induced by a novel intestinal metabolite of ginseng saponin in human hepatocellular carcinoma cells 总被引:1,自引:0,他引:1
Ming YL Song G Chen LH Zheng ZZ Chen ZY Ouyang GL Tong QX 《Cell biology international》2007,31(10):1265-1273
20-O-(beta-D-glucopyranosyl)-20(S)-protopanaxadiol (IH-901), a novel intestinal bacterial metabolite of ginseng protopanaxadiol saponins, is reported to induce apoptosis in a variety of cancer cells. We purified the compound and measured its in vitro anti-tumor activity. IH-901 inhibited cell growth of human hepatocellular carcinoma SMMC7721 cells in a dose- and time-dependent manner. We also found that IH-901 induced apoptotic cell death concurrent with cell cycle arrest in G0-G1 phase in SMMC7721 cells. At the molecular level, we show that IH-901 upregulates cytochrome c, p53, and Bax expression, and downregulates pro-caspase-3 and pro-caspase-9 expressions in a dose-dependent manner, while the levels of Bcl-2 and Bcl-X(L) were unchanged in IH-901-treated SMMC7721 cells. These results provide significant insight into the anticarcinogenic action of IH-901. 相似文献
126.
Mei F Zhong J Yang X Ouyang X Zhang S Hu X Ma Q Lu J Ryu S Deng X 《Biomacromolecules》2007,8(12):3729-3735
Significant effort has been devoted to fabricating various biomaterials to satisfy specific clinical requirements. In this study, we developed a new type of guided tissue regeneration (GTR) membrane by electrospinning a suspension consisting of poly( l-lactic acid), multiwalled carbon nanotubes, and hydroxyapatite (PLLA/MWNTs/HA). MWNTs/HA nanoparticles were uniformly dispersed in the membranes, and the degradation characteristics were far improved. Cytologic research revealed that the PLLA/MWNTs/HA membrane enhanced the adhesion and proliferation of periodontal ligament cells (PDLCs) by 30% and inhibited the adhesion and proliferation of gingival epithelial cells by 30% also, compared with the control group. After PDLCs were seeded into the PLLA/MWNTs/HA membrane, cell/membrane composites were implanted into the leg muscle pouches of immunodeficient mice. Histologic examinations showed that PDLCs attached on the membranes functioned well in vivo. This new type of membrane shows excellent dual biological functions and satisfied the requirement of the GTR technique successfully in spite of a monolayer structure. Compared with other GTR membranes on sale or in research, the membrane can simplify the manufacturing process, reduce the fabrication cost, and avoid possible mistakes in clinical application. Moreover, it does not need to be taken out after surgery. PLLA/MWNTs/HA membranes have shown great potential for GTR and tissue engineering. 相似文献
127.
128.
Guo Xiaoping Sun Junming Liang Jinning Zhu Siran Zhang Mingyuan Yang Lichao Huang Xuejing Xue Kangning Mo Zhongxiang Wen Sha Hu Bing Liu Jiajuan Ouyang Yiqiang He Min 《Molecular biology reports》2022,49(10):9335-9344
Molecular Biology Reports - Lung injury caused by pulmonary inflammation is one of the main manifestations of respiratory diseases. Vasorin (VASN) is a cell-surface glycoprotein encoded by the VASN... 相似文献
129.
Yong Liang De-Yun Zhang Shuhong Ouyang Jingzhong Xie Qiuhong Wu Zhenzhong Wang Yu Cui Ping Lu Dong Zhang Zi-Ji Liu Jie Zhu Yong-Xing Chen Yan Zhang Ming-Cheng Luo Jan Dvorak Naxin Huo Qixin Sun Yong-Qiang Gu Zhiyong Liu 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2015,128(8):1617-1629
130.
Chaoyu Cui Junxi Jiang Hui Ouyang Cheng Li Dengquan Liu Ting Huang 《Journal of Phytopathology》2015,163(9):780-782
In 2013, bitter rot of grape was observed in Changbei Vineyard located in Nanchang City, Jiangxi Province, China. Greeneria species was consistently isolated from the diseased grape berries (Vitis labruscana cv. Kyoho) at approximately 91% of isolation rate in three independent experiments. The species was identified as Greeneria uvicola based on the morphological characteristics, cultural appearance and sequence analysis. Koch's postulates were fulfilled through pathogenicity tests on detached healthy Kyoho grape berries. To our knowledge, this is the first report of G. uvicola causing bitter rot of grape in China. 相似文献