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991.
应用抗巨噬细胞表面分子Mac-1单克隆抗体(M1/70和M18/2)处理巨噬细胞,观察M1/70和M18/2对杜氏利曼原虫前鞭毛体入侵巨噬细胞的抑制作用。结果,经上述单抗处理后巨噬细胞,对杜氏利什曼原虫的易感性明显降低,其原虫感染率和受染巨噬细胞内入侵的原虫数量减低,原虫对巨噬细胞的入侵过程及速度也减慢。M1/70和M18/2两种单抗同时应用,则对原虫侵入巨噬细胞的抑制作用更为显著,巨噬细胞受染率为13.8%,且受染巨噬细胞内入侵的原虫数量大多仅有1~2个。提示,M1/70和M18/2单克隆抗体可以通过与巨噬细胞表面Mac-1的结合,干扰巨噬细胞表面分子上与利什曼原虫相结合的连接位点,抑制利什曼原虫对巨噬细胞的入侵。 相似文献
992.
目的 分析儿童学习困难的影响因素,为提高儿童的学习状况提供有效的依据。方法 采用整群随机抽样的方法,对在江苏省昆山市抽取的5 132名6~12岁儿童(其父母、老师等)进行学习困难及其影响因素的问卷调查。结果 本研究调查发现昆山市儿童学习困难发生率为16.29%。多因素Logistic回归分析发现:年龄每增加1岁,学习困难的发生风险降低18%;女性与男性相比,学习困难发生风险相对较低,OR(95%CI)值为0.56(0.42~0.76);与主要照顾者为母亲的相比,主要照顾者为祖辈或其他可增加儿童学习困难发生风险,OR(95%CI)值为1.73(1.23~2.43);与民主的教养方式相比,保护式的教养方式可以增加儿童学习困难的发生风险,OR(95%CI)值为1.65(1.12~2.41);与家庭和睦的相比,不断争吵的家庭可以增加儿童学习困难的发生风险,其OR(95%CI)值为2.59(1.07~6.25)。结论 昆山市儿童学习困难的发生率仍较高,应从学校、家庭、主要照顾者等多个方面来提高儿童的学习状况。 相似文献
993.
目的:分析不同年龄层次人工流产孕妇的心理状态,进行有针对性的心理护理干预及避孕宣教,从而预防人工流产并发症的发生、降低人工流产率。方法:对本院2013年1月-2014年1月收治的1200例孕妇进行术前心理状态分析,并进行术前、术中、术后护理干预及术后中医艾灸应用和避孕宣教,统计护理干预结果。结果:干预后,1200例患者中,人工流产综合症72例(6.0%),子宫穿孔6例(0.5%),人流不全12例(1.0%),感染4例(0.3%)。其中初产妇52例(4.3%),未婚24例(2.0%),经产妇18例(1.5%)。人工流产的并发症发生率为7.8%,明显低于国内报道13.5%(P〈0.05)。干预前后,患者的心理状态评分的比较差异有统计学意义(P〈0.05)。结论:有效的心理护理可以减少人工流产并发症的发生率,提高孕妇心理应激能力;另外,避孕宣教可降低人工流产率及未婚妊娠的发生率,这些措施均值得在临床中推广应用。 相似文献
994.
目的研究无纺布手术衣及敷料与棉织布手术衣及敷料对层流手术室动态下空气质量的影响,为提高层流手术间动态空气质量措施提供科学依据。方法选取医院2013年2-10月骨科全髋关节置换手术患者100例,随机分成A、B两组,每组各50例,A组用无纺布手术衣及敷料,B组用棉织布手术衣及敷料;采用沉降法和浮游法对两组手术间动态空气质量进行监测,并将监测结果进行比较。结果沉降法监测中A、B两组手术间平均空气沉降菌菌落数整体比较差异有统计学意义(t=3.12,P<0.01),在不同时点比较中,麻醉前A、B两组手术间空气沉降菌菌落数比较差异无统计学意义,在切皮前、手术中、缝合前及手术结束后各时点两组比较差异均有统计学意义(P<0.05);浮游法监测中A、B两组手术间平均空气浮游菌菌落数整体比较差异有统计学意义(t=3.78,P<0.01),在不同时点比较中,麻醉前A、B两组手术间空气浮游菌菌落数比较差异无统计学意义,在切皮前、手术中、缝合前、手术结束后各时点两组比较差异均有统计学意义(P<0.05)。结论使用无纺布手术衣及敷料的手术其手术间动态空气质量明显优于使用传统棉织布手术衣及敷料。 相似文献
995.
Jingfu Cui Mo Zhu Shijun ZhuGuixian Wang MM Yaozeng XuDechun Geng MD PhD 《The Journal of surgical research》2014
Background
Wear particle-induced periprosthetic osteolysis that results in aseptic loosening is the most common cause of long-term failure after total joint replacement.Materials and methods
Icariin (ICA), a flavonoid isolated from Epimedium pubescens, inhibits osteoclast formation, but its effects on wear particle-induced inflammatory osteoclastogenesis remains unclear. We investigated the role of ICA in the regulation of osteoclast differentiation in a murine macrophage cell line (RAW264.7), which is stimulated by titanium (Ti) particles and the receptor activator of NF-κB ligand.Results
ICA effectively inhibited osteoclast formation and bone resorption in the differentiation medium. ICA (10−7 mol/L) significantly reduced the number of tartrate-resistant acid phosphatase-positive cells compared with the control, and significantly reduced the percentage of the surface covered by resorption lacunae. Quantitative real-time polymerase chain reaction analysis showed that ICA inhibited messenger RNA expression for the receptor activator of nuclear factor-κB, cathepsin K, tartrate-resistant acid phosphatase-positive, and matrix metalloproteinase-9 in RAW264.7 cells stimulated by Ti particles and receptor activator of NF-κB ligand. ICA also reduced pro-inflammatory cytokine expression of interleukin-1β and tumor necrosis factor-α in RAW264.7 cells cultured with Ti particles. In addition, incubation with cholecystokinin-8 showed that ICA had no toxic effects on RAW264.7 cells.Conclusions
ICA possibly elicited inhibitory effects on inflammatory osteoclastogenesis induced by Ti particles, indicating that ICA may be useful for the prevention and treatment of wear particle-induced osteolysis. 相似文献996.
997.
Chunyang Jiang Shun Zhang Hongliang Liu Zhizhong Guan Qiang Zeng Cheng Zhang Rongrong Lei Tao Xia Zhenglun Wang Lu Yang Yihu Chen Xue Wu Xiaofei Zhang Yushan Cui Linyu Yu Aiguo Wang 《Neuromolecular medicine》2014,16(1):94-105
Fluorine, a toxic and reactive element, is widely prevalent throughout the environment and can induce toxicity when absorbed into the body. This study was to explore the possible mechanisms of developmental neurotoxicity in rats treated with different levels of sodium fluoride (NaF). The rats’ intelligence, as well as changes in neuronal morphology, glucose absorption, and functional gene expression within the brain were determined using the Morris water maze test, transmission electron microscopy, small-animal magnetic resonance imaging and Positron emission tomography and computed tomography, and Western blotting techniques. We found that NaF treatment-impaired learning and memory in these rats. Furthermore, NaF caused neuronal degeneration, decreased brain glucose utilization, decreased the protein expression of glucose transporter 1 and glial fibrillary acidic protein, and increased levels of brain-derived neurotrophic factor in the rat brains. The developmental neurotoxicity of fluoride may be closely associated with low glucose utilization and neurodegenerative changes. 相似文献
998.
Qian Cui Eric J. Vanman Dongtao Wei Wenjing Yang Lei Jia Qinglin Zhang 《Social cognitive and affective neuroscience》2014,9(10):1472-1480
The ability of a deceiver to track a victim’s ongoing judgments about the truthfulness of the deceit can be critical for successful deception. However, no study has yet investigated the neural circuits underlying receiving a judgment about one’s lie. To explore this issue, we used a modified Guilty Knowledge Test in a mock murder situation to simultaneously record the neural responses involved in producing deception and later when judgments of that deception were made. Producing deception recruited the bilateral inferior parietal lobules (IPLs), right ventral lateral prefrontal (VLPF) areas and right striatum, among which the activation of the right VLPF contributed mostly to diagnosing the identities of the participants, correctly diagnosing 81.25% of ‘murderers’ and 81.25% of ‘innocents’. Moreover, the participant’s response when their deception was successful uniquely recruited the right middle frontal gyrus, bilateral IPLs, bilateral orbitofrontal cortices, bilateral middle temporal gyrus and left cerebellum, among which the right IPL contributed mostly to diagnosing participants’ identities, correctly diagnosing 93.75% of murderers and 87.5% of innocents. This study shows that neural activity associated with being a successful liar (or not) is a feasible indicator for detecting lies and may be more valid than neural activity associated with producing deception. 相似文献
999.
Chen Tan Wei Han Xingpeng Liu Xuehong Hu Jianguo Liu Junyu Cui Junxia Li 《International journal of cardiology》2014
Background
Left atrial diverticulum (LAD) is not rare in patients with atrial fibrillation (AF). Recent reports focused on its morphology however data on its electrophysiological characteristics are lacking. Our study aims to investigate the electrogram and impedance features of LAD.Methods
This study included 24 patients (mean age, 58.5 ± 10.7 years) with LAD undergoing catheter ablation for AF and 24 gender-and-age-matched individuals without LAD as controls. A bipolar LAD electroanatomic map was acquired in sinus rhythm from all study participants. Points were acquired for diverticulum in the LAD group and for corresponding areas in the control group. Electrogram deflections were counted, bipolar voltage and impedance were measured for each point, and average ?impedance and highest ?impedance were calculated.Results
A total of 234 points were collected in the two groups. In the LAD vs. control group, median (Q1, Q3) of electrogram deflections was 6 (5, 7) and 4 (4, 5) (P < 0.0001), respectively, voltage was not significantly different (1.58 ± 0.68 mV vs. 1.28 ± 0.65 mV, P = 0.10), and average ?impedance was significantly higher in the LAD group (19.5 ± 9.0 Ω vs 3.9 ± 1.7 Ω, P < 0.0001). A cut-off value of 9.5 Ω for ?impedance predicted LAD with sensitivity, specificity, and positive and negative predictive values of 83.5%, 92.8%, 92.1% and 84.9%, respectively.Conclusions
Electrogram was more fractionated and impedance was higher at LAD than in corresponding areas without LAD, which might help to differentiate LAD during catheter ablation for AF. 相似文献1000.
Zuo-Ming Zhang Yibaina Wang Rong Huang Yu-Peng Liu Xia Li Fu-Lan Hu Lin Zhu Fan Wang Bin-Bin Cui Xin-Shu Dong Ya-Shuang Zhao 《Journal of cancer research and clinical oncology》2014,140(12):2119-2127