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排序方式: 共有1733条查询结果,搜索用时 31 毫秒
71.
PAN Dong DU Ya Rong LI Rong SHEN Ai Hua LIU Xiao Dong LI Chuan Yuan HU Bu Rong 《Biomedical and environmental sciences : BES》2022,35(3):194-205
Objective SET8 is a member of the SET domain-containing family and the only known lysine methyltransferase(KMT) that monomethylates lysine 20 of histone H4(H4 K20 me1). SET8 has been implicated in many essential cellular processes, including cell cycle regulation, DNA replication, DNA damage response, and carcinogenesis. There is no conclusive evidence, however, regarding the effect of SET8 on radiotherapy. In the current study we determined the efficacy of SET8 inhibition on radiotherapy of tum... 相似文献
72.
QU Pei SHAO Zhi Ang WANG Bing HE Jin Peng ZHANG Ya Nan WEI Wen Jun HUA Jun Rui ZHOU Heng LU Dong DING Nan WANG Ju Fang 《Biomedical and environmental sciences : BES》2022,35(5):437-447
Objective miR-663 a has been reported to be downregulated by X-ray irradiation and participates in radiation-induced bystander effect via TGF-β1. The goal of this study was to explore the role of mi R-663 a during radiation-induced Epithelium-to-mesenchymal transition(EMT).Methods TGF-β1 or IR was used to induce EMT. After mi R-663 a transfection, cell migration and cell morphological changes were detected and the expression levels of mi R-663 a, TGF-β1, and EMT-related factors were quantified.R... 相似文献
73.
Valerii E. Orel Marina Tselepi Thanos Mitrelias Alexander Rykhalskyi Andriy Romanov Valerii B. Orel Anatoliy Shevchenko Anatoliy Burlaka Sergey Lukin Crispin H.W. Barnes 《Nanomedicine : nanotechnology, biology, and medicine》2018,14(4):1249-1256
Modulation of reactive oxygen and nitrogen species in a tumor could be exploited for nanotherapeutic benefits. We investigate the antitumor effect in Walker-256 carcinosarcoma of magnetic nanodots composed of doxorubicin-loaded Fe3O4 nanoparticles combined with electromagnetic fields. Treatment using the magnetic nanodot with the largest hysteresis loop area (3402 erg/g) had the greatest antitumor effect with the minimum growth factor 0.49 ± 0.02 day–1 (compared to 0.58 ± 0.02 day–1 for conventional doxorubicin). Electron spin resonance spectra of Walker-256 carcinosarcoma treated with the nanodots, indicate an increase of 2.7 times of free iron (that promotes the formation of highly reactive oxygen species), using the nanodot with the largest hysteresis loop area, compared to conventional doxorubicin treatment as well as increases in ubisemiquinone, lactoferrin, NO-FeS-proteins. Hence, we provide evidence that the designed magnetic nanodots can modulate the tumor redox state. We discuss the implications of these results for cancer nanotherapy. 相似文献
74.
Małgorzata M. Dobrzyńska Ewa A. Jankowska‐Steifer Ewa J. Tyrkiel Aneta Gajowik Joanna Radzikowska Krzysztof A. Pachocki 《Environmental toxicology》2014,29(11):1301-1313
Bisphenol A (BPA) is employed in the manufacturing of epoxy, polyester‐styrene, and polycarbonate resins, which are used for the production of baby and water bottles and reusable containers, food and beverage packing, dental fillings and sealants. The study was designed to examine the effects of 8‐week exposure (a full cycle of spermatogenesis) to BPA alone and in a combination with X‐irradiation on the reproductive organs and germ cells of adult and pubescent male mice. Pzh:Sfis male mice were exposed to BPA (5, 10, and 20 mg/kg) or X‐rays (0.05 Gy) or to a combination of both (0.05 Gy + 5 mg/kg bw BPA). The following parameters were examined: sperm count, sperm motility, sperm morphology, and DNA damage in male gametes. Both BPA and X‐rays alone diminished sperm quality. BPA exposure significantly reduced sperm count in pubescent males compared to adult mice, with degenerative changes detected in seminiferous epithelium. This may suggest a higher susceptibility of germ cells of younger males to BPA action. Combined BPA with X‐ray treatment enhanced the harmful effect induced by BPA alone in male germ cells of adult males, whereas low‐dose irradiation showed sometimes protective or additive effects in pubescent mice. © 2013 Wiley Periodicals, Inc. Environ Toxicol 29: 1301–1313, 2014. 相似文献
75.
76.
Vijay K. Singh Stephen Y. Wise Oluseyi O. Fatanmi Lindsay A. Beattie Elizabeth J. Ducey Thomas M. Seed 《Journal of radiation research》2014,55(1):41-53
The purpose of this study was to elucidate the role of alpha-tocopherol succinate (TS)- and AMD3100-mobilized progenitors in mitigating combined injury associated with acute radiation exposure in combination with secondary physical wounding. CD2F1 mice were exposed to high doses of cobalt-60 gamma-radiation and then transfused intravenously with 5 million peripheral blood mononuclear cells (PBMCs) from TS- and AMD3100-injected mice after irradiation. Within 1 h after irradiation, mice were exposed to secondary wounding. Mice were observed for 30 d after irradiation and cytokine analysis was conducted by multiplex Luminex assay at various time-points after irradiation and wounding. Our results initially demonstrated that transfusion of TS-mobilized progenitors from normal mice enhanced survival of acutely irradiated mice exposed 24 h prior to transfusion to supralethal doses (11.5–12.5 Gy) of 60Co gamma-radiation. Subsequently, comparable transfusions of TS-mobilized progenitors were shown to significantly mitigate severe combined injuries in acutely irradiated mice. TS administered 24 h before irradiation was able to protect mice against combined injury as well. Cytokine results demonstrated that wounding modulates irradiation-induced cytokines. This study further supports the conclusion that the infusion of TS-mobilized progenitor-containing PBMCs acts as a bridging therapy in radiation-combined-injury mice. We suggest that this novel bridging therapeutic approach involving the infusion of TS-mobilized hematopoietic progenitors following acute radiation exposure or combined injury might be applicable to humans. 相似文献
77.
Yuki Hirota Shin-Ichiro Masunaga Natsuko Kondo Shinji Kawabata Hirokazu Hirakawa Hirohiko Yajima Akira Fujimori Koji Ono Toshihiko Kuroiwa Shin-Ichi Miyatake 《Journal of radiation research》2014,55(1):75-83
Ionizing radiation is applied as the standard treatment for glioblastoma multiforme (GBM). However, radiotherapy remains merely palliative, not curative, because of the existence of glioma stem cells (GSCs), which are regarded as highly radioresistant to low linear-energy-transfer (LET) photons. Here we analyzed whether or not high-LET particles can overcome the radioresistance of GSCs. Glioma stem-like cells (GSLCs) were induced from the GBM cell line A172 in stem cell culture medium. The phenotypes of GSLCs and wild-type cells were confirmed using stem cell markers. These cells were irradiated with 60Co gamma rays or reactor neutron beams. Under neutron-beam irradiation, high-LET proton particles can be produced through elastic scattering or nitrogen capture reaction. Radiosensitivity was assessed by a colony-forming assay, and the DNA double-strand breaks (DSBs) were assessed by a histone gamma-H2AX focus detection assay. In stem cell culture medium, GSLCs could form neurosphere-like cells and express neural stem cell markers (Sox2 and Musashi) abundantly in comparison with their parental cells. GSLCs were significantly more radioresistant to gamma rays than their parental cells, but neutron beams overcame this resistance. There were significantly fewer gamma-H2AX foci in the A172 GSLCs 24 h after irradiation with gamma rays than in their parental cultured cells, while there was no apparent difference following neutron-beam irradiation. High-LET radiation can overcome the radioresistance of GSLCs by producing unrepairable DNA DSBs. High-LET radiation therapy might have the potential to overcome GBM''s resistance to X-rays in a clinical setting. 相似文献
78.
79.
Scott Nugent Sebastien Tremblay Kewei W. Chen Napatkamon Ayutyanont Auttawut Roontiva Christian-Alexandre Castellano Melanie Fortier Maggie Roy Alexandre Courchesne-Loyer Christian Bocti Martin Lepage Eric Turcotte Tamas Fulop Eric M. Reiman Stephen C. Cunnane 《Neurobiology of aging》2014
The extent to which the age-related decline in regional brain glucose uptake also applies to other important brain fuels is presently unknown. Ketones are the brain's major alternative fuel to glucose, so we developed a dual tracer positron emission tomography protocol to quantify and compare regional cerebral metabolic rates for glucose and the ketone, acetoacetate. Twenty healthy young adults (mean age, 26 years) and 24 healthy older adults (mean age, 74 years) were studied. In comparison with younger adults, older adults had 8 ± 6% (mean ± SD) lower cerebral metabolic rates for glucose in gray matter as a whole (p = 0.035), specifically in several frontal, temporal, and subcortical regions, as well as in the cingulate and insula (p ≤ 0.01, false discovery rate correction). The effect of age on cerebral metabolic rates for acetoacetate in gray matter did not reach significance (p = 0.11). Rate constants (min−1) of glucose (Kg) and acetoacetate (Ka) were significantly lower (−11 ± 6%; [p = 0.005], and −19 ± 5%; [p = 0.006], respectively) in older adults compared with younger adults. There were differential effects of age on Kg and Ka as seen by significant interaction effects in the caudate (p = 0.030) and post-central gyrus (p = 0.023). The acetoacetate index, which expresses the scaled residuals of the voxel-wise linear regression of glucose on ketone uptake, identifies regions taking up higher or lower amounts of acetoacetate relative to glucose. The acetoacetate index was higher in the caudate of young adults when compared with older adults (p ≤ 0.05 false discovery rate correction). This study provides new information about glucose and ketone metabolism in the human brain and a comparison of the extent to which their regional use changes during normal aging. 相似文献
80.
Caroline Steglich Ramos Andréia Souza Gonçalves Larissa Cardoso Marinho Melissa Ameloti Gomes Avelino Vera Aparecida Saddi Aryanne Cristina Lopes Renata Toscano Simões Isabela Jubé Wastowski 《Human immunology》2014
The human leukocyte antigen G (HLA-G) is a non-classical HLA class I molecule predominantly expressed in trophoblastic placental cells to protect the fetus during pregnancy. However, evidence has shown that this molecule may be implicated in the immune escape mechanism of tumor cells. Thus, the aim of this study was to evaluate the frequency of 14-bp insertion/deletion HLA-G polymorphism, as well as the expression of this molecule in patients with invasive breast ductal carcinoma (IDC). A significant association between the expression of HLA-G and the presence of metastasis in lymph nodes (p = 0.01) was observed and the expression of HLA-G was significantly higher in patients with shorter survival time (p = 0.03). The analysis suggests that the polymorphism observed in patients with IDC may be inducing a higher expression of the HLA-G molecule, which may possibly contribute to shorter survival time and a worse clinical prognosis for such patients. 相似文献