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11.
Clinical trials are probably the most informative experiments to help an understanding of multiple sclerosis (MS) biology. Recent successes with CD20‐depleting antibodies have focused attention towards B cell subsets as important mediators in MS. The trial of tabalumab (NTC00882999), which inhibits B cell activation factor (BAFF), is reported and reviewed and this trial is contrasted with the trial on the inhibition of a proliferation‐inducing ligand (APRIL) and BAFF using atacicept (NCT00642902). Both tabalumab and atacicept induce depletion of mature B cells and inhibit antibody formation, but they fail to deplete memory B cells and do not inhibit relapsing MS. Atacicept is reported to augment memory B cell responses and may precipitate relapse, suggesting the importance of APRIL. However, BAFF inhibition can enhance peripheral blood memory B cell responses, which was not associated with augmented relapse. Although other interpretations are possible, these data further support the hypothesis that memory B cells may be of central importance in relapsing MS, as they are the major CD20+ B cell subset expressing APRIL receptors. They also suggest that quantitative and/or qualitative differences in B cell responses or other factors, such as an immune‐regulatory effect associated with APRIL, may be important in determining whether MS reactivates following neutralization of peripheral B cell maturation and survival factors.  相似文献   
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《Vaccine》2020,38(31):4783-4791
A novel coronavirus (CoV), Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in late 2019 in Wuhan, China and has since spread as a global pandemic. Safe and effective vaccines are thus urgently needed to reduce the significant morbidity and mortality of Coronavirus Disease 2019 (COVID-19) disease and ease the major economic impact. There has been an unprecedented rapid response by vaccine developers with now over one hundred vaccine candidates in development and at least six having reached clinical trials. However, a major challenge during rapid development is to avoid safety issues both by thoughtful vaccine design and by thorough evaluation in a timely manner. A syndrome of “disease enhancement” has been reported in the past for a few viral vaccines where those immunized suffered increased severity or death when they later encountered the virus or were found to have an increased frequency of infection. Animal models allowed scientists to determine the underlying mechanism for the former in the case of Respiratory syncytial virus (RSV) vaccine and have been utilized to design and screen new RSV vaccine candidates. Because some Middle East respiratory syndrome (MERS) and SARS-CoV-1 vaccines have shown evidence of disease enhancement in some animal models, this is a particular concern for SARS-CoV-2 vaccines. To address this challenge, the Coalition for Epidemic Preparedness Innovations (CEPI) and the Brighton Collaboration (BC) Safety Platform for Emergency vACcines (SPEAC) convened a scientific working meeting on March 12 and 13, 2020 of experts in the field of vaccine immunology and coronaviruses to consider what vaccine designs could reduce safety concerns and how animal models and immunological assessments in early clinical trials can help to assess the risk. This report summarizes the evidence presented and provides considerations for safety assessment of COVID-19 vaccine candidates in accelerated vaccine development.  相似文献   
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Many studies have shown a special interaction between LAG3 and PD-1 in T cell inhibition, while the co-expression and effect of LAG3 and PD-1 on T cells in breast cancer patients are still not very clear. Here, with strict exclusion criteria, 88 patients with breast cancer and 18 healthy controls were enrolled. The percentages of LAG3+PD-1+ T cells in their peripheral blood (PBL) and tumor infiltrating T cells (TIL) were analyzed by flow cytometry, which showed an increase in TILs but no difference in PBLs and presented differences in TILs in different molecular subtypes (P < 0.05). In triple-negative breast cancer (TNBC), the highest percentages were observed, while in ER+/PR+ breast cancer, the lowest percentages were observed; however, these percentages were not different in different clinical stages (P > 0.05). Immunohistochemical staining showed that the expression of their ligands, PD-L1, MHC class II molecular and FGL1, was inconsistent in different molecular subtypes and clinical stages. Analysis of the functions of T cells with different phenotypes showed that the proliferation and secretion capacity of LAG3+PD-1+ T cells was obviously exhausted, with more than a two-fold of decrease compared with the groups of single positive LAG3 or PD-1 (P < 0.05). Finally, in a mouse model of TNBC, the dual blockade of LAG3 and PD-1 was indicated to achieve a better anti-tumour effect than either one alone (P < 0.05), which may provide a new strategy for the immunoregulatory treatment of patients with TNBC in the future.  相似文献   
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目的研究通阳中药葱白提取物(AYMOE)对低压低氧诱导的血小板激活和促凝状态的影响。方法将42只成年雄性SD大鼠随机分为对照组(暴露于常压常氧环境)、低压低氧组(Hyp组,暴露于低压低氧环境)、Hyp+AYMOE-100组(暴露于低压低氧环境并口服AYMOE 100 mg/kg)、Hyp+AYMOE-200组(暴露于低压低氧环境并口服AYMOE 200 mg/kg)、Hyp+AYMOE-300组(暴露于低压低氧环境并口服AYMOE 300 mg/kg)、Hyp+anti-CD42c组(暴露于低压低氧环境并尾静脉注射antiCD42c 5 mg/kg)、Hyp+AYMOE-200+rh Lyn组[暴露于低压低氧环境并口服AYMOE 200 mg/kg联合尾静脉注射重组人酪氨酸蛋白激酶Lyn(rh Lyn) 4.8 mg/kg],每组6只。低压低氧暴露7 d后,ELISA检测各组大鼠血清血栓素A2(TXA2)以及血小板激活因子(PAF)含量,检测大鼠血小板的凝集率,HE染色观察大鼠肺组织病理变化,Western blot检测GPIb-Ⅸ-Ⅴ、Lyn、磷酸化的Lyn(p-Lyn)的表达。结果与对照组比较,暴露于低压低氧的各组大鼠血清TXA2、PAF水平及血小板凝集率升高,GPIb-Ⅸ-Ⅴ、Lyn、p-Lyn蛋白表达上调(P <0.05)。与Hyp组相比,Hyp+AYMOE-100组、Hyp+AYMOE-200组、Hyp+AYMOE-300组的血小板凝集率、血清TXA2、PAF的水平降低,差异均有统计学意义(P <0.05),其中以Hyp+AYMOE-200组抑制效果最明显(P <0.05)。与对照组比较,Hyp组大鼠因低氧而发生血管堵塞,肺静脉血管腔空间狭小;与Hyp组相比,Hyp+AYMOE-200组大鼠肺静脉血管栓塞明显缓解。与Hyp组相比,Hyp+anti-CD42c组和Hyp+AYMOE-200组GPIb-Ⅸ-Ⅴ、Lyn、p-Lyn蛋白表达下调,差异均有统计学意义(P <0.05)。与Hyp+AYMOE-200组比较,Hyp+AYMOE-200+rh Lyn组血小板凝集率、血清TXA2和PAF水平均较高,Lyn和p-Lyn蛋白表达均增加,差异均有统计学意义(P <0.05)。结论 AYMOE可通过抑制GPIb-Ⅸ-Ⅴ和Lyn减少低压低氧诱导的血小板激活并改善促凝状态。  相似文献   
16.
《Drug discovery today》2022,27(8):2373-2385
Autophagy, an evolutionarily highly conserved cellular degradation process, plays the Janus role (either cytoprotective or death-promoting) in colorectal cancer, so the targeting of several key autophagic pathways with small-molecule compounds may be a new therapeutic strategy. In this review, we discuss autophagy-associated cell death pathways and key cytoprotective autophagy pathways in colorectal cancer. Moreover, we summarize a series of small-molecule compounds that have the potential to modulate autophagy-associated cell death or cytoprotective autophagy for therapeutic purposes. Taken together, these findings demonstrate the Janus role of autophagy in colorectal cancer, and shed new light on the exploitation of a growing number of small-molecule compounds to target autophagy in future cancer drug discovery.  相似文献   
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Pituitary Adenylate Cyclase-Activating Polypeptide (PACAP) plays an important role in cytoprotection, inflammation and cardiovascular regulation. Thus, we studied the involvement of PACAP in atherogenesis. Differentiated human THP-1 macrophages (MΦ) were stimulated with oxidized low-density lipoproteins (oxLDL) and the influence of PACAP38 treatment on lipid content and TNF release was determined. To test the effect of PACAP deficiency (PACAP?/?) on the development of atherosclerosis under standard chow (SC) or cholesterol-enriched diet (CED) in vivo, PACAP?/? mice were crossbred with ApoE?/? to generate PACAP?/?/ApoE?/? mice. Blood cholesterol and triglyceride levels were quantified. Lumen stenosis in the brachiocephalic trunk, cellularity and amounts of pro-inflammatory as well as autophagy-, apoptosis- and necroptosis-relevant proteins were analysed in atherosclerotic plaques by quantitative immunohistochemistry. In vitro, PACAP38 inhibited oxLDL-induced intracellular lipid storage as well as TNF release in MФ. In vivo, after SC, but not under CED, PACAP?/?/ApoE?/? mice showed an increased lumen stenosis compared to ApoE?/? mice. In atherosclerotic plaques of PACAP?/?/ApoE?/? mice, the immunoreactive areas of TNF+, IL-1β+, autophagic, apoptotic and necroptotic cells were increased. In contrast, the overall cell density was decreased compared to ApoE?/? under SC, while no differences were seen under CED. Similar plasma cholesterol levels were observed in PACAP?/?/ApoE?/? and ApoE?/? mice under the respective feeding regime. Thus, PACAP?/-/ApoE?/? mice represent a novel mouse model of accelerated atherosclerosis where CED is not required. Our data indicate that PACAP acts as an endogenous atheroprotective neuropeptide. Thus, stable PACAP agonists may have potential as anti-atherosclerotic therapeutics. The specific PACAP receptor(s) mediating atheroprotection remain(s) to be identified.  相似文献   
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目的探究补肾活血组方对人流术后月经过少的临床疗效。方法将90例人流术后月经过少患者随机分为两组,观察组给予补肾活血组方治疗,对照组给予常规治疗,对比两组疗效。结果观察组有效率显著高于对照组(P0.05);治疗后,观察组行经时间显著高于对照组(P0.05);观察组子宫内膜厚度显著高于对照组(P0.05)。结论人流术后月经过少患者经补肾活血法治疗,可有效促进月经恢复,疗效显著。  相似文献   
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