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991.
Background:Aging is a phenomenon that human''s physiology and psychology is progressive decline for natural environment. Health Qigong, as a convenient and effective exercise therapy,is widely used for anti-aging. However, there are no systematic reviews or meta-analysises to evaluate the efficacy and safety of Health Qigong on anti-aging.Methods:We will systematically search for 7 English databases(PubMed, Excerpta Medica Database, MEDLINE, Web of Science, Cochrane Library, SpringerLink, and WHO International Clinical Trials Registry Platform) and 4 Chinese databases(namely the China National Knowledge Infrastructure Database, the Wanfang Database, the Chinese Scientific Journal Database, and the Chinese BioMedical Literature Database) from their inceptions to August 2020. Randomized controlled trials (RCTs) using Health Qigong to anti-aging will be included. After the selection and extraction of eligible studies, a meta-analysis will be undertaken to assess the efficacy and safety of Health Qigong on anti-aging. Moreover, study selection, data extraction, and the evaluation of the methodological quality of trials will each be independently completed by at least 2 researchers. The Review Manager Software V.5.3 will be employed for meta-analysis to assess the risk of bias, data synthesis, and subgroup analysis.Results:This review will provide the latest knowledge and evidence on the efficacy and safety of Health Qigong for anti-aging through the analysis of various evaluation scales.Conclusion:The conclusion of this review will help clinicians provide effective exercise therapy for anti-aging.Registration number:INPLASY202090017  相似文献   
992.
On the basis of endocrine therapy for patients with low burden metastatic prostate cancer (LBMP), the clinical efficacy and quality of life were compared between prostate-only directed radiotherapy (PODT) and prostate and metastasis radiotherapy (PMRT).From November 2009 to November 2015, total 91 patients newly diagnosed with LBMP were retrospectively analyzed, of which 52 patients received PODT and 39 patients received PMRT. The biochemical failure free interval (IBF), prostate specific survival (PCSS), and overall survival (OS) time were compared between the 2 groups, and expanded prostate cancer index composite (EPIC) scale was used to evaluate the difference in quality of life between the 2 groups.The median IBF of the PODT group was 31 months, which was significantly lower than the 39 months of the PMRT group (P < .05); the 5-year OS and PCSS were 58.9%, 65.3% in PODT group, and 58.9%, 71.79% in PMRT group, respectively. There was no significant between the 2 groups (P > .05); the side effects of acute radiotherapy in PMRT group were significantly higher than PODT group (P < .05), especially in bone marrow suppression and gastrointestinal reactions; The scores of urinary system function and intestinal system function in PMRT group were significantly higher than PODT group at the end of radiotherapy, 3 months after radiotherapy, and 6 months after radiotherapy (P < .05). The score of sexual function in PMRT group was significantly lower than that in PODT group after radiotherapy (P < .05), and higher than that in PORT group at other follow-up time points (P < .05). The hormone function was decreased at each follow-up time point in 2 groups, and there was no significant difference between the 2 groups (P > .05).Patients with LBMP receiving PMRT can improve IBF, but cannot increase PCSS and OS, and increase the incidence of acute radiation injury.  相似文献   
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Nanomedicines (NMs) offer new solutions for cancer diagnosis and therapy. However, extension of progression-free interval and overall survival time achieved by Food and Drug Administration-approved NMs remain modest. To develop next generation NMs to achieve superior anticancer activities, it is crucial to investigate and understand the correlation between the physicochemical properties of NMs (particle size in particular) and their interactions with biological systems to establish criteria for NM optimization. Here, we systematically evaluated the size-dependent biological profiles of three monodisperse drug–silica nanoconjugates (NCs; 20, 50, and 200 nm) through both experiments and mathematical modeling and aimed to identify the optimal size for the most effective anticancer drug delivery. Among the three NCs investigated, the 50-nm NC shows the highest tumor tissue retention integrated over time, which is the collective outcome of deep tumor tissue penetration and efficient cancer cell internalization as well as slow tumor clearance, and thus, the highest efficacy against both primary and metastatic tumors in vivo.Over the last two to three decades, consensus has been reached that the size of anticancer nanomedicines (NMs) plays a pivotal role in determining their biodistribution, tumor penetration, cellular internalization, and clearance from blood plasma and tissues as well as excretion from body, and thus, it has significant impact on overall therapeutic efficacy against cancers (17). Although most clinically approved anticancer NMs have size ranging from 100 to 200 nm (8, 9), recent studies showed that anticancer NMs with smaller sizes exhibited enhanced performance in vivo, such as greater tissue penetration and enhanced tumor inhibition, particularly those with size around or smaller than 50 nm (57, 1012). As such, there has been a major push recently in the field of anticancer NM to miniaturize nanoparticle (NP) size using novel chemistry and engineering design (1317). One unanswered question, however, is whether additional miniaturization of NM size would be necessary and result in additional improved anticancer efficacy. Widely evaluated small molecular therapeutics (<1,500 Da and <2 nm) can traverse most tumor tissues freely (18). However, they diffuse away from tumor tissues rapidly and get cleared primarily into tumor blood capillaries, leading to minimal tumor accumulation (18). Macromolecules of relatively low molecular masses (<40,000 Da and <10 nm) were also shown to have low overall tumor retention because of both rapid permeation into and clearance from tumor tissues, behaving to some extent like small molecule drugs (18, 19). In conjunction with the renal clearance threshold (<10–15 nm) (20, 21) and interstitial/lymphatic fenestration (<20 nm) (22) for NPs, it becomes essential to carefully and comprehensively evaluate the in vivo behavior and anticancer efficacy of NMs in the size range of 20–50 nm to determine the optimal size of NM for cancer therapy.In this study, we used monodisperse drug–silica nanoconjugates (NCs) that have identical physiochemical properties, except for size, to investigate the size-dependent biodistribution and tumor tissue penetration and clearance as well as the overall efficacy. We focused on the NCs of 20 and 50 nm in this particularly interesting size range as well as the NC of 200 nm, the upper size limit of systemic NM to extravasate leaky tumor vasculature, which has a cutoff pore size larger than 200 nm for most tumors (23). Among these three representative sizes, the 50-nm NC showed the optimal balance of deep tissue penetration and high retention in tumors, which is in contrast with its larger counterpart (the 200-nm NC) of limited tumor tissue penetration and smaller counterpart (the 20-nm NC) of fast clearance from tumors, leading to overall low tumor retention for both. Therefore, 50 nm could be or could be close to the optimal size of NCs in the studied size range of 20–200 nm, ensuring not only the efficient distribution in, but also the protracted availability of drug-containing NC to the tumor tissues, resulting in superior anticancer efficacy against both primary and metastatic tumors.  相似文献   
996.
目的 了解中国鼠疫耶尔森菌不同分离株之间的染色体结构差异,探索染色体重排在鼠疫菌中发生的原因及用于菌株遗传特征识别和亲缘关系分析的可能性.方法 以完成全基因组测序的首株鼠疫菌株CO92(美国)为参考株,以从中国分离出的已完成全基因组测序的4株鼠疫菌株(内蒙古91001、云南剑川D182038、云南玉龙D106004、西藏那曲Z176003)为对比株,根据美国国立生物技术信息中心网站(http://www.ncbi.nlm.nih.gov/genome)上公布的这5株鼠疫菌的染色体序列及染色体上所有编码基因序列间的相似性,将鼠疫菌染色体人为的划分成多个大的DNA节段(染色体板块),确定这些板块在不同鼠疫菌株间排列方式的差异以及板块之间的断裂区片段的基因组成;根据菌株两两比较所得的重排差异结果,分析菌株间的亲缘关系.结果 除Z176003菌株外,CO92、D182038、D106004、91001菌株可被分成44个相对独立的染色体板块,板块内部基因组成和排列高度稳定,板块之间可以相对移动.与参考株CO92菌株比较,D182038、D106004菌株染色体均存在13处重排,Z176003菌株染色体存在14处重排,91001菌株染色体存在37处板块排列顺序的改变.菌株间两两比较,D106004与Z176003菌株之间仅有8处染色体板块排列方式不同,表明二者的亲缘关系最为接近.CO92菌株染色体上的相邻板块之间存在43个断裂区,有39个断裂区的DNA片段含有插入序列,其中25个插入序列为IS100.结论 鼠疫菌基因组具有一定的流动性,不同菌株间的染色体结构存在较大差异,染色体重排事件发生的原因与其拥有的插入序列密切相关.菌株间染色体的重排差异,能用于菌株遗传特征的识别和亲缘远近关系的分析.  相似文献   
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Background

In this study, we aimed to evaluate the protective effect of tight glucose control during cardiopulmonary bypass on myocardium in adult nondiabetic patients undergoing isolated aortic valve replacement in a prospective and randomized trial.

Methods

Sixty-five adult nondiabetic patients undergoing selective isolated aortic valve replacement were enrolled and randomly assigned to an insulin group (patients received a continuous insulin infusion during surgery; n = 33) or a control group (patients were not administered insulin unless their blood glucose level exceeded 200 mg/dL; n = 32). Cardiac troponin I was assayed preoperatively, and then at 2, 6, 12, 24, and 48 hours after aortic cross-declamping. The pre-, intra-, and postoperative relevant data of all selected patients were analyzed.

Results

Tight glucose control reduced postoperative peak release by 48% for cardiac troponin I compared with the control group (0.48 ± 0.12 vs 0.71 ± 0.17 ng/mL; P < 0.0001). Patients with continuous insulin infusion had lower peak inotropic score during the first postoperative 24 hours and peak level of blood glucose (5.8 ± 2.2 vs 8.2 ± 3.1 μg/kg/min; P < 0.0001; 131.9 ± 23.8 vs 191.1 ± 38.5 mg/dL; P < 0.001, respectively), shorter duration of mechanical ventilation and intensive care unit stay and hospital stay compared with the control group (11.6 ± 2.9 hours vs 14.8 ± 3.5 hours; P = 0.0002; 28.4 ± 7.2 hours vs 36.5 ± 7.8 hours; P < 0.0001; 9.4 ± 3.3 days vs 11.5 ± 4.2 days; P = 0.0283, respectively).

Conclusions

Tight glucose control during cardiopulmonary bypass might provide myocardial protection in adult nondiabetic patients undergoing isolated aortic valve replacement.  相似文献   
999.
Lu  Mingming  Yuan  Fei  Zhang  Lichen  Peng  Peng  Qiao  Huiyu  Cai  Jianming  Zhao  Xihai 《Neuroradiology》2020,62(2):221-221
Neuroradiology - The above article was published online with incorrect presentation of author name. Mingming is the given name and Lu is&nbsp;the family name. The presentation of the author...  相似文献   
1000.
Because of their high efficiency and sharp emission, perovskite light-emitting diodes are a promising candidate for next-generation lighting techniques. However, the relatively poor stability of perovskite light-emitting diodes lowers their utility. Therefore, a highly stable perovskite light-emitting diode has to be developed to meet the commercial demand. Herein, we report a highly stable CsPbBr3 light-emitting diode via simple polymer treatment. The addition of 2-methyl-2-oxazoline in perovskite film assists the formation of CsPbBr3 nanocrystals, improving the quality and photoluminescence property of perovskite film. Based on such CsPbBr3 nanocrystals and polymer hybrid film, our device presents a high external quantum efficiency and luminance of around 3.0% and 16 648 cd m−2, respectively. Moreover, an excellent device half-lifetime of more than 2.4 hours has been achieved, under continuous operation at a relatively high initial luminance of 1000 cd m−2, representing one of the most stable PeLEDs operated at such high initial luminance.

The 2-methyl-2-oxazoline additive induced the formation of high-quality CsPbBr3 nanocrystals and a stable PeLED with a half-lifetime of 2.4 hours at high initial luminance of 1000 cd m−2 was demonstrated, representing one of the most stable PeLEDs.  相似文献   
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