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81.
The diagnostic potential of MPT63‐derived HLA‐A*0201‐restricted CD8+T‐cell epitopes for active pulmonary tuberculosis 下载免费PDF全文
Zhiliang Duan Dezhou Li Qingjun Jia Juanjuan Xu Xinyu Chen Zhigang Xu Huifang Liu Bokun Chen Jinsheng Wen 《Microbiology and immunology》2015,59(12):705-715
MPT63 protein is found only in Mycobacterium tuberculosis complex, including M. tuberculosis and M. bovis. Detection of MPT63‐specific IFN‐γ‐secreting T cells could be useful for the diagnosis of tuberculosis (TB) diseases. In the present study, the HLA‐A*0201 restriction of ten predicted MPT63‐derived CD8 + T‐cell epitopes was assessed on the basis of T2 cell line and HLA‐A*0201 transgenic mice. The diagnostic potential of immunogenic peptides in active pulmonary TB patients was evaluated using an IFN‐γ enzyme‐linked immunospot assay. It was found that five peptides bound to HLA‐A*0201 with high affinity, whereas the remaining peptides exhibited low affinity for HLA‐A*0201. Five immunogenic peptides (MPT6318–26, MPT6329–37, MPT6320–28, MPT635–14 and MPT6310–19) elicited large numbers of cytotoxic IFN‐γ‐secreting T cells in HLA‐A*0201 transgenic mice. Each of the five immunogenic peptides was recognized by peripheral blood mononuclear cells from 45% to 73% of 40 HLA‐A*0201 positive TB patients. The total diagnostic sensitivity of the five immunogenic peptides was higher than that of a T‐SPOT.TB assay (based on ESAT‐6 and CFP‐10) (93% versus 90%). It is noticeable that the diagnostic sensitivity of the combination of five immunogenic peptides and T‐SPOT.TB assay reached 100%. These MPT63‐derived HLA‐A*0201‐restricted CD8 + T‐cell epitopes would likely contribute to the immunological diagnosis of M. tuberculosis infection and may provide the components for designing an effective TB vaccine. 相似文献
82.
不同林龄杉木氮素的获取策略 总被引:4,自引:0,他引:4
为了探讨不同林龄杉木人工林氮素获取策略,选择了江西千烟洲森林生态研究站红壤区的3种林龄杉木人工林(5年生幼龄林、13年生中龄林和30年生成熟林)作为研究对象,利用稳定性同位素~(15)N示踪技术研究了它们的氮素吸收策略。结果表明,杉木对硝态氮的吸收受林龄影响,成熟林的吸收速率最高,为(5.72±0.24)μg N g~(-1)干重h~(-1),而中龄林和幼龄林的吸收速率相当,分别为(1.57±0.13)μg N g~(-1)干重h~(-1)和(2.36±0.22)μg N g~(-1)干重h~(-1)。幼龄林((34.33±1.20)μg N g~(-1)干重h~(-1))和成熟林((34.18±2.32)μg N g~(-1)干重h~(-1))对铵态氮的吸收速率相似,均显著高于中龄林((23.33±1.39)μg N g~(-1)干重h~(-1))。杉木对甘氨酸的吸收不受林龄的影响。3种年龄的杉木均对铵态氮表现出强的获取能力,其中成熟林杉木对硝态氮的获取能力明显弱于对铵态氮的获取,但却强于对甘氨酸的获取。这样的结果反映了林龄能影响杉木人工林对无机氮的吸收,但未影响对有机氮的吸收;杉木偏好吸收铵态氮,对硝态氮和甘氨酸的吸收很少。如果能把氮素形态考虑进对杉木人工林的施肥管理当中,那么可能会极大地改善杉木的生产力。 相似文献
83.
Feng En Lo Po Jung Lu Min Kuang Tsai June Han Lee Christopher Wen Chi Pang Wen Jackson Pui Man Wai Chwen Keng Tsao Po Huang Chiang Shu Yu Lyu Ko Lu Ma Ying-Chen Chi Chu-Shiu Li Chwen-Chi Liu Xifeng Wu 《PloS one》2016,11(4)
ObjectiveTo assess the benefits of regular exercise in reducing harms associated with betel quid (BQ) chewing.MethodsThe study cohort, 419,378 individuals, participated in a medical screening program between 1994 and 2008, with 38,324 male and 1,495 female chewers, who consumed 5–15 quids of BQ a day. Physical activity of each individual, based on “MET-hour/week”, was classified as “inactive” or “active”, where activity started from a daily 15 minutes/day or more of brisk walking (≥3.75 MET-hour/week). Hazard ratios for mortality and remaining years in life expectancy were calculated.ResultsNearly one fifth (18.7%) of men, but only 0.7% of women were chewers. Chewers had a 10-fold increase in oral cancer risk; and a 2-3-fold increase in mortality from lung, esophagus and liver cancer, cardiovascular disease, and diabetes, with doubling of all-cause mortality. More than half of chewers were physically inactive (59%). Physical activity was beneficial for chewers, with a reduction of all-cause mortality by 19%. Inactive chewers had their lifespan shortened by 6.3 years, compared to non-chewers, but being active, chewers improved their health by gaining 2.5 years. The improvement, however, fell short of offsetting the harms from chewing.ConclusionsChewers had serious health consequences, but being physically active, chewers could mitigate some of these adverse effects, and extend life expectancy by 2.5 years and reduce mortality by one fifth. Encouraging exercise, in addition to quitting chewing, remains the best advice for 1.5 million chewers in Taiwan. 相似文献
84.
Lifang Zou Guihua Tu Wei Xie Shiyao Wen Qiuyu Xie Shuangmei Liu Guilin Li Yun Gao Hong Xu Shouyu Wang Yun Xue Bing Wu Qiulan Lv Mofeng Ying Xi Zhang Shangdong Liang 《Purinergic signalling》2016,12(1):127-137
Adenosine triphosphate (ATP) acts on P2X receptors to initiate signal transmission. P2X7 receptors play a role in the pathophysiological process of myocardial ischemic injury. Long noncoding RNAs (lncRNAs) participate in numerous biological functions independent of protein translation. LncRNAs are implicated in nervous system diseases. This study investigated the effects of NONRATT021972 small interference RNA (siRNA) on the pathophysiologic processes mediated by P2X7 receptors in stellate ganglia (SG) after myocardial ischemic injury. Our results demonstrated that the expression of NONRATT021972 in SG was significantly higher in the myocardial ischemic (MI) group than in the control group. Treatment of MI rats with NONRATT021972 siRNA, the P2X7 antagonist brilliant blue G (BBG), or P2X7 siRNA improved the histology of injured ischemic cardiac tissues and decreased the elevated concentrations of serum myocardial enzymes, creatine kinase (CK), CK isoform MB (CK-MB), lactate dehydrogenase (LDH) and aspartate aminotransferase (AST) compared to the MI rats. NONRATT021972 siRNA, BBG, or P2X7 siRNA treatment in MI rats decreased the expression levels of P2X7 immunoreactivity, P2X7 messenger RNA (mRNA), and P2X7 protein, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and phosphorylated p38 mitogen-activated protein kinase (p38 MAPK) in the SG compared to MI rats. NONRATT021972 siRNA treatment prevented the pathophysiologic processes mediated by P2X7 receptors in the SG after myocardial ischemic injury. 相似文献
85.
Jing Zhang Donghui Wen Cui Zhao Xiaoyan Tang 《Applied microbiology and biotechnology》2014,98(2):863-873
Bioaugmentation with degrading bacteria is an effective method to improve the treatment of refractory industrial wastewater; nevertheless there were controversial opinions about the fate of inoculated bacteria and microbial community dynamics. In this study, two lab-scale sequencing batch reactors filled with modified zeolite were used to treat a coking wastewater with pyridine and quinoline shock load, and a bacterial consortium containing three degrading strains was added in one reactor for bioaugmentation. During 120-day operation, the bioaugmented reactor removed over 99 % pyridine, 99 % quinoline, 85 % TOC, 65 % COD, and 95 % NO3 ?-N with higher resistance to the shock load than the non-bioaugmented reactor. Based on the terminal restriction fragment length polymorphism of 16S rDNA, bacterial community diversity increased in the bioaugmented reactor. Principal component analysis revealed that, to cope with the shock load, the indigenous bacterial community recovered to the initial structure by acclimatizing itself constantly to the inhospitable environment; but bioaugmentation accelerated the shift of whole bacterial community, resulting in a far different structure from the initial one. Canonical correspondence analysis indicated that the environmental parameters of pyridine, quinoline, TOC, and NO3 ?-N had close negative correlations with bioaugmentation; and NH3-N and COD were the main parameters to impact on the bacterial community changes and treatment efficiency. 相似文献
86.
Xue Gong Chao Lin Jian Cheng Jiansheng Su Hang Zhao Tianlin Liu Xuejun Wen Peng Zhao 《PloS one》2015,10(6)
Three dimensional multicellular aggregate, also referred to as cell spheroid or microtissue, is an indispensable tool for in vitro evaluating antitumor activity and drug efficacy. Compared with classical cellular monolayer, multicellular tumor spheroid (MCTS) offers a more rational platform to predict in vivo drug efficacy and toxicity. Nevertheless, traditional processing methods such as plastic dish culture with nonadhesive surfaces are regularly time-consuming, laborious and difficult to provide uniform-sized spheroids, thus causing poor reproducibility of experimental data and impeding high-throughput drug screening. In order to provide a robust and effective platform for in vitro drug evaluation, we present an agarose scaffold prepared with the template containing uniform-sized micro-wells in commercially available cell culture plates. The agarose scaffold allows for good adjustment of MCTS size and large-scale production of MCTS. Transparent agarose scaffold also allows for monitoring of spheroid formation under an optical microscopy. The formation of MCTS from MCF-7 cells was prepared using different-size-well templates and systematically investigated in terms of spheroid growth curve, circularity, and cell viability. The doxorubicin cytotoxicity against MCF-7 spheroid and MCF-7 monolayer cells was compared. The drug penetration behavior, cell cycle distribution, cell apoptosis, and gene expression were also evaluated in MCF-7 spheroid. The findings of this study indicate that, compared with cellular monolayer, MCTS provides a valuable platform for the assessment of therapeutic candidates in an in vivo-mimic microenvironment, and thus has great potential for use in drug discovery and tumor biology research. 相似文献
87.
88.
Quantum‐Dot Sensitized Solar Cells Employing Hierarchical Cu2S Microspheres Wrapped by Reduced Graphene Oxide Nanosheets as Effective Counter Electrodes 下载免费PDF全文
Hierarchical Cu2S microspheres wrapped by reduced graphene oxide (RGO) nanosheets are prepared via a one‐step solvothermal process. The amount of graphene oxide used in the synthesis process has a remarkable effect on the features of Cu2S microspheres. Compared to Pt and Cu2S electrodes, RGO‐Cu2S electrodes show better electrocatalytic activity, greater stability, lower charge‐transfer resistance, and higher exchange current density. As expected, RGO‐Cu2S electrodes exhibit superior performance when functioning as counter electrodes in CdS/CdSe quantum dot‐sensitized solar cells (QDSSCs) using a polysulfide electrolyte. A power conversion efficiency up to 3.85% is achieved for the QDSSC employing an optimized RGO‐Cu2S counter electrode, which is higher than those of the QDSSCs featuring Pt (2.14%) and Cu2S (3.39%) counter electrodes. 相似文献
89.
Artesunate exerts an anti‐immunosuppressive effect on cervical cancer by inhibiting PGE2 production and Foxp3 expression 下载免费PDF全文
90.
水资源短缺是影响黄土高原雨养农业发展的关键性因素,雨水资源开发是缓解该地区水资源短缺的有效措施.本研究利用管式 TDR 系统监测21年红富士老果园0~300 cm土层土壤含水率变化,分析了雨水集聚深层入渗(RWCI)系统下黄土高原旱作山地果园土壤水分时空分布特征.结果表明: RWCI系统能够显著增加果园土壤含水率,特别是40~80 cm土层(土壤含水率低值区)土壤含水率,在该区域,不同设计深度(40、60和80 cm)RWCI处理(RWCI40、RWCI60和RWCI80)年均土壤含水率分别较鱼鳞坑(CK)处理提高75.3%、85.4%和62.4%,分别较裸露坡地(BS)处理提高39.2%、47.2%和29.1%.RWCI40、RWCI60和RWCI80处理土壤水分入渗最大深度分别为80、120和180 cm,显著深于CK处理(60 cm),其中土壤水分变化幅度最大的土层分别主要发生在0~60、0~100和0~120 cm.在果树整个生育期内,RWCI处理土壤平均含水率(0~300 cm)以RWCI80处理最大,其次是RWCI40和RWCI60处理.总体来看,RWCI系统是黄土高原实现雨水资源化和农业高效用水的有效措施. 相似文献