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71.
Yu-Jue Wang Wen Liu Chi Chen Li-Meng Yan Jun Song Kun-Yuan Guo Gang Wang Qing-Hong Wu Wei-Wang Gu 《PloS one》2013,8(3)
Background
The radiation-induced energy metabolism dysfunction related to injury and radiation doses is largely elusive. The purpose of this study is to investigate the early response of energy metabolism in small intestinal tissue and its correlation with pathologic lesion after total body X-ray irradiation (TBI) in Tibet minipigs.Methods and Results
30 Tibet minipigs were assigned into 6 groups including 5 experimental groups and one control group with 6 animals each group. The minipigs in these experimental groups were subjected to a TBI of 2, 5, 8, 11, and 14 Gy, respectively. Small intestine tissues were collected at 24 h following X-ray exposure and analyzed by histology and high performance liquid chromatography (HPLC). DNA contents in this tissue were also examined. Irradiation causes pathologic lesions and mitochondrial abnormalities. The Deoxyribonucleic acid (DNA) content-corrected and uncorrected adenosine-triphosphate (ATP) and total adenine nucleotides (TAN) were significantly reduced in a dose-dependent manner by 2–8 Gy exposure, and no further reduction was observed over 8 Gy.Conclusion
TBI induced injury is highly dependent on the irradiation dosage in small intestine and inversely correlates with the energy metabolism, with its reduction potentially indicating the severity of injury. 相似文献72.
Hongxing Zhang Fang Zhou Chen Li Min Kong He Liu Peng Zhang Song Zhang Junli Cao Licai Zhang Hong Ma 《PloS one》2013,8(2)
Background
Dexmedetomidine (DEX) has been used under perioperative settings as an adjuvant to enhance the analgesic property of local anesthetics by some anesthesiologists. However, the analgesic mechanisms and neurotoxicity of DEX were poorly understood. This study examined the effect of DEX alone on inflammatory pain, and it also examined the underlying molecular mechanisms of DEX in the spinal cord. Furthermore, in vivo and in vitro experiments were performed to investigate the neurotoxicity of DEX on the spinal cord and cortical neurons.Methods
This study used adult, male Kunming mice. In the acute inflammatory model, the left hind-paws of mice were intradermally injected with pH 5.0 PBS while chronic constrictive injury (CCI) of the sciatic nerve was used to duplicate the neuropathic pain condition. Thermal paw withdrawal latency and mechanical paw withdrawal threshold were tested with a radiant heat test and the Von Frey method, respectively. Locomotor activity and motor coordination were evaluated using the inverted mesh test. Western blotting examined spinal ERK1/2, p-ERK1/2, caspase-3 and β-actin expressions, while spinal c-Fos protein expression was realized with immunohistochemical staining. Hematoxylin eosin (HE) staining was used to examine the pathological impacts of intrathecal DEX on the spinal cord. DAPI (4′,6-diamidino-2-phenylindole) staining was used to observe cell death under an immunofluorescence microscope.Results
Intra-plantar pH 5.0 PBS-induced acute pain required spinal ERK1/2 activation. Inhibition of spinal ERK1/2 signaling by intrathecal injection of DEX displayed a robust analgesia, via a α2-receptor dependent manner. The analgesic properties of DEX were validated in CCI mice. In vivo studies showed that intrathecal DEX has no significant pathological impacts on the spinal cord, and in vitro experiments indicated that DEX has potential protective effects of lidocaine-induced neural cell death.Conclusion
Intrathecal injection of DEX alone or as an adjuvant might be potential for pain relief. 相似文献73.
Chuanfu Zhang Shaofu Qiu Yong Wang Lihua Qi Rongzhang Hao Xuelin Liu Yun Shi Xiaofeng Hu Daizhi An Zhenjun Li Peng Li Ligui Wang Jiajun Cui Pan Wang Liuyu Huang John D. Klena Hongbin Song 《PloS one》2013,8(6)
Multidrug resistant microbes present in the environment are a potential public health risk. In this study, we investigate the presence of New Delhi metallo-β-lactamase 1 (NDM-1) producing bacteria in the 99 water samples in Beijing City, including river water, treated drinking water, raw water samples from the pools and sewage from 4 comprehensive hospitals. For the bla
NDM-1 positive isolate, antimicrobial susceptibility testing was further analyzed, and Pulsed Field Gel Electrophoresis (PFGE) was performed to determine the genetic relationship among the NDM-1 producing isolates from sewage and human, as well as the clinical strains without NDM-1. The results indicate that there was a higher isolation of NDM-1 producing Acinetobacter baumannii from the sewage of the hospitals, while no NDM-1 producing isolates were recovered from samples obtained from the river, drinking, or fishpond water. Surprisingly, these isolates were markedly different from the clinical isolates in drug resistance and pulsed field gel electrophoresis profiles, suggesting different evolutionary relationships. Our results showed that the hospital sewage may be one of the diffusion reservoirs of NDM-1 producing bacteria. 相似文献
74.
Samuel Q. Li Adam T. Cheuk Jack F. Shern Young K. Song Laura Hurd Hongling Liao Jun S. Wei Javed Khan 《PloS one》2013,8(10)
Rhabdomyosarcoma (RMS) is the most common childhood soft tissue sarcoma. Despite advances in modern therapy, patients with relapsed or metastatic disease have a very poor clinical prognosis. Fibroblast Growth Factor Receptor 4 (FGFR4) is a cell surface tyrosine kinase receptor that is involved in normal myogenesis and muscle regeneration, but not commonly expressed in differentiated muscle tissues. Amplification and mutational activation of FGFR4 has been reported in RMS and promotes tumor progression. Therefore, FGFR4 is a tractable therapeutic target for patients with RMS. In this study, we used a chimeric Ba/F3 TEL-FGFR4 construct to test five tyrosine kinase inhibitors reported to specifically inhibit FGFRs in the nanomolar range. We found ponatinib (AP24534) to be the most potent FGFR4 inhibitor with an IC50 in the nanomolar range. Ponatinib inhibited the growth of RMS cells expressing wild-type or mutated FGFR4 through increased apoptosis. Phosphorylation of wild-type and mutated FGFR4 as well as its downstream target STAT3 was also suppressed by ponatinib. Finally, ponatinib treatment inhibited tumor growth in a RMS mouse model expressing mutated FGFR4. Therefore, our data suggests that ponatinib is a potentially effective therapeutic agent for RMS tumors that are driven by a dysregulated FGFR4 signaling pathway. 相似文献
75.
76.
Lee Yun-Ah Kim Se-Hong Kim Ha-Na Song Sang-Wook 《Biological trace element research》2020,193(2):311-318
Biological Trace Element Research - Obesity is a risk factor for metabolic syndrome, dyslipidemia, hypertension, insulin resistance, type 2 diabetes mellitus, and cardiovascular disease. However,... 相似文献
77.
Yang Xuefang He Yingying Song Xi’E Yuan Xiangyang Li Yongfeng Sun Dasheng 《Plant and Soil》2020,448(1-2):369-381
Plant and Soil - The incidence of herbicide-resistant blackgrass is escalating in wheat fields; the development of alternatives to traditional herbicides is crucial. Allelopathic wheat can suppress... 相似文献
78.
Kumar P. S. Ling C. Y. Zhou Z. B. Dong Y. L. Sun C. L. Song Y. X. Wong N. K. Ju J. H. 《Microbiology》2020,89(4):483-492
Microbiology - Marine actinobacteria particularly from marine environments are believed to be inexhaustible sources of biologically active molecules for biomedical and industrial applications. We... 相似文献
79.
Chen Jiajia Yang Saishuai Wu Chunshuai Cui Zhiming Wan Yangyang Xu Guanhua Bao Guofeng Zhang Jinlong Chen Chu Song Dianwen 《Neurochemical research》2020,45(10):2302-2311
Neurochemical Research - Spinal cord injury (SCI) is one of the diseases with high probability of causing disability in human beings, and there is no reliable treatment at present. Neuronal... 相似文献
80.
Hong-Ge Yang Yan-Mei Jiao Hui-Huang Huang Chao Zhang Ji-Yuan Zhang Ruo-Nan Xu Jin-Wen Song Xing Fan Lei Jin Ming Shi Fu-Sheng Wang 《Microbiology and immunology》2020,64(6):458-468
HIV replication can be inhibited by CXCR5+CD8 T cells (follicular cytotoxic T cell [TFC]) which transfer into B-cell follicles where latent HIV infection persists. However, how cytokines affect TFC remain unclear. Understanding which cytokines show the ability to affect TFC could be a key strategy toward curing HIV. Similar mechanisms could be used for the growth and transfer of TFCs and follicular helper T (TFH) cells; as a result, we hypothesized that cytokines IL-6, IL-21, and transforming growth factor-β (TGF-β), which are necessary for the differentiation of TFH cells, could also dictate the development of TFCs. In this work, lymph node mononuclear cells and peripheral blood mononuclear cells from HIV-infected individuals were cocultured with IL-6, IL-21, and TGF-β. We then carried out T-cell receptor (TCR) repertoire analysis to compare the differences between CXCR5– and CXCR5+CD8 T cells. Our results showed that the percentage and function of TFC can be enhanced by stimulation with TGF-β. Besides, TGF-β stimulation enhanced the diversity of TCR and complementarity-determining region 3 sequences. HIV DNA showed a negative correlation with TFC. The use of TGF-β to promote the expression of CXCR5+CD8 T cells could become a new treatment approach for curing HIV. 相似文献