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91.
目的研究梗死前心绞痛(缺血预适应)与缺血后适应叠加对老年急性心肌梗死患者介入治疗后冠状动脉血流速度及预后的影响。方法选取12h内接受急症冠状动脉介入治疗的心肌梗死患者106例,35例有梗死前心绞痛症状并接受缺血后适应者为预适应与后适应叠加组(IPC+Postcon),37例单纯接受缺血后适应干预者为后适应组(Postcon),其余34例为单纯再灌注组(IR),测定校正TIMI帧数(CTFC)、血肌酸磷酸激酶(CK)、肌酸磷酸激酶同工酶(CK-MB)、丙二醛,术后8w测定室壁运动记分。结果IPC+Postcon组与Postcon组CTFC明显快于IR组(27.12±5.84,26.98±5.76vs.31.53±7.41,P<0.05),CK峰值与CK-MB峰值明显低于IR组(1243.35±801.31U/L,1238.67±817.26U/Lvs.1697.76±965.63U/L,P<0.05;120.97±78.28U/L,117.94±75.81U/Lvs.174.45±92.67U/L,P<0.05),IPC+Postcon组与Postcon组间无统计学差异;3组患者入院时MDA均高于对照组,术后各时点IPC+Postcon组与Postcon组均低于IR组。术后8wIPC+Postcon组与Postcon组室壁运动恢复优于IR组(1.16±0.12,1.17±0.11vs.1.31±0.15,P<0.05)。结论缺血后适应与预适应一样可以改善介入治疗后冠状动脉血流速度,减少自由基的生成,改善心功能。预适应与后适应叠加对上述功能的改善并无增强作用。  相似文献   
92.
炎症因子在急性冠状动脉综合征预后中的作用   总被引:1,自引:1,他引:1  
为探讨C-反应蛋白、纤维蛋白原和肿瘤坏死因子α等炎症因子在急性冠状动脉综合征患者预后中的作用,连续观察了76例急性冠状动脉综合征患者入院时上述指标的变化,随访7~12个月,记录住院期间和出院后新发生的心血管事件.结果发现,随访期内发生心血管事件者C-反应蛋白和纤维蛋白原浓度高于未发生者,而肿瘤坏死因子α在对照组和急性冠状动脉综合征患者的浓度无差别;多因素Logistic回归分析发现,C-反应蛋白和纤维蛋白原是心血管事件的独立危险因素.表明C-反应蛋白和纤维蛋白原是判断急性冠状动脉综合征患者短期预后的有用指标,肿瘤坏死因子α对判断急性冠状动脉综合征患者的预后无价值.  相似文献   
93.
Persons with advanced human immunodeficiency virus type one (HIV-1) infection seek medical advice for a wide range of neurological disorders including, but not limited to, peripheral neuropathy, toxoplasmosis, cryptococcal meningitis, cytomegalovirus retinitis progressive multifocal leukoencephalopathy, lymphoma and dementia. The diagnosis of HIV-1-associated dementia (HAD) induced as a direct consequence of HIV infection of the brain comes commonly by exclusion. Diagnostic decisions can often be clouded by concomitant depression, motor impairments, and lethargy that follow debilitating immune suppression and weight loss. Indeed, cognitive, motor and behavior abnormalities underlie a variety of neurological dysfunctions associated with advanced HIV-1 infection. Thus, even combinations of clinical, laboratory and neuroimaging tests [for example, magnetic resonance imaging (MRI), computed tomography (CT), single photon emission computed tomography (SPECT) and positron emission tomography (PET)] often fail to provide conclusive diagnostic information. Nonetheless, the recent development of quantitative MR spectroscopic imaging has improved diagnostic possibilities for HAD. We are pleased to discuss these developments as well as taking a forward look into what will soon be made available to improve neuroimaging diagnostic precision. New MR and SPECT testing are being developed in our laboratories and elsewhere both for animal model systems and in humans with HIV-1 disease. Such tests can facilitate dynamic measures of HIV-1 neuropathogenesis providing information for disease events that even 2 years ago were unattainable.  相似文献   
94.
Abstract

In this work, the expression of secreted frizzled related protein 2 (SFRP2) in rheumatoid arthritis (RA) model rats and the mechanisms of SFRP2 on the RA pathogenesis were investigated. Data suggested that SFRP2 was significantly down-regulated in RA model rats compared with normal control, and overexpression of SFRP2 suppressed the RA pathogenesis and the canonical Wnt signaling in fibroblast-like synovial cells (FLS) from RA model rats, whereas knockdown of SFRP2 got an opposite observation. Interestingly, 5-azadC treatment up-regulated the SFRP2 expression, inhibited the FLS proliferation, suppressed the expression of IL-6 and IL-8 and the fibronectin production, suggesting that the decreased SFRP2 in RA model rats was due to the DNA methylation. Furthermore, DNMT1 knockdown up-regulated the SFRP2 expression, DNMT1 overexpression inhibited the SFRP2, and the quantitative methylation-specific PCR (qMSP) confirmed that the DNMT1 has direct methylation roles for the SFRP2 promoter, leading to a regulation of FLS proliferation and fibronectin expression in RA model rats. In addition, up-regulated MeCP2 was involved in the SFRP2 regulation and the pathogenesis of RA model rats, and MeCP2 and DNMT1 have synergistic inhibition roles in the SFRP2 expression. Combination of DNMT1 and DNA methylation may be a promising treatment strategy for individuals with RA in which SFRP2 is down-regulated.  相似文献   
95.
Study ObjectiveTo prospectively examine the association between sleep quality and incident cancer risk in the elderly.MethodsA total of 10,036 participants aged ≥50 years free of cancer at baseline from the English Longitudinal Study of Ageing at wave 4 (2008) were included, and followed up until 2016. The primary endpoint was new onset physician-diagnosed cancer. Sleep quality was assessed by four questions regarding the frequency of sleep problems and overall subjective feeling of sleep quality in the last month, with higher score denoting poorer sleep quality. The multivariable Cox regression model was used to calculate hazard ratio (HR) with 95% confidence interval (CI) for incident cancer risk according to sleep quality.ResultsAt 8-year follow-up, a total of 745 (7.4%) participants developed cancer. Compared with good sleep quality at baseline, HR (95% CI) for incident cancer risk was 1.328 (1.061, 1.662) for intermediate quality, 1.586 (1.149, 2.189) for poor quality. Similarly, compared with maintaining good sleep quality in the first 4 years, HR (95% CI) for incident cancer risk was 1.615 (1.208, 2.160) for maintaining intermediate quality and 1.608 (1.043, 2.480) for maintaining poor quality. The exclusion of participants with family history of cancer or abnormal sleep duration yielded consistent results.ConclusionsPoor sleep quality is positively associated with the long-term risk of developing cancer in an elderly cohort. Both medical staffs and the general public should pay more attention to improving sleep hygiene.  相似文献   
96.
97.
With the careful modulation of the relative ratio of Y3+/Eu3+and Y3+/Tb3+, two series of bimetallic RE-CPs (EuxY1−x and TbxY1−x) were successfully obtained through the isomorphous substitution method. Interestingly, the introduction of Y3+ ions does not change the fluorescence characteristic peak of 1-Eu and 1-Tb, but enhances its fluorescence lifetime and quantum yield. Experimental and theoretical simulation results show the co-doping process changes the intramolecular energy transfer process and reduces the non-radiative transition resulting from concentration quenching. Eu0.1Y0.9 and Tb0.1Y0.9 with the largest luminescence lifetime were selected as the representative research objects, their potential application for the detection of toxic metal ions and organic molecules was further investigated. Interestingly, Eu0.1Y0.9 and Tb0.1Y0.9 demonstrate high sensitivity and good selectivity towards Fe3+, Cr3+ and acetone. Besides, fine fluorescence visibility provides the necessary conditions for the preparation of simple and fast response fluorescent test papers in order to achieve real-time and convenient detection of these toxic materials.

Two series of doped coordination polymers (EuxY1−x and TbxY1−x) through isomorphous substitution method utilizing Y3+ in place of partial Eu3+/Tb3+ were obtained. The doped materials could detect Fe3+, Cr3+, and acetone selectively and sensitively.  相似文献   
98.
朱晓静  周梁 《海峡药学》2020,32(1):99-102
目的分析心房颤动(AF)患者CYP2C9、VKORC1基因多态性与华法林药物敏感度的关系。方法根据华法林给药累计剂量,将27例AF患者分为低起效剂量组和高起效剂量组;根据达标时间,分为短起效时间组和长起效时间组。比较高、低起效剂量组和长、短起效时间组CYP2C9、VKORC1不同基因型华法林的起效剂量和起效时间。结果高、低起效剂量组rs1057910(CYP2C9*3)及长、短起效时间组VKORC1 rs9923231基因构成差异有统计学意义(P<0.05)。与AA基因型比较,CYP2C9 rs1057910 AC基因型华法林起效剂量降低,VKORC1 rs9923231 GA基因型华法林起效时间缩短(P<0.05)。华法林药物敏感度可分为低度敏感、中度敏感和高度敏感3种。结论应结合临床实际对口服华法林行抗凝治疗的AF患者进行CYP2C9、VKORC1基因多态性检测,以便从基因类型角度合理分配华法林剂量。  相似文献   
99.
The effect of temperature on the toxicities of four diamide insecticides (chlorantraniliprole, cyantraniliprole, flubendiamide, tetraniliprole) against three lepidopteran insects (Helicoverpa armigera, Plutella xylostella, Athetis lepigone) were determined from 15 to 35 °C by exposing third-instar larvae to dip-treated cabbage leaf. The results indicated that increase in temperature led to an increase significantly and regularly in the toxicities of the four diamide insecticides against P. xylostella and H. armigera, but not for A. lepigone. The temperature coefficients (TCs) of the four diamide insecticides increased from 15 to 35 °C. Tetraniliprole for H. armigera (+825.83), chlorantraniliprole for P. xylostella (+315.65) and cyantraniliprole for H. armigera (+225.77) exhibited high positive TCs. For A. lepigone, temperature had a positively weak or no effect on the toxicities of most of the diamide insecticides from 20 to 30 °C, but a higher effect from 30 to 35 °C. In addition, the toxicities of chlorantraniliprole, cyantraniliprole and tetraniliprole all decreased from 15 to 20 °C. This study can guide pest managers in choosing suitable ambient field temperature when spraying diamide insecticides against lepidopteran insects.  相似文献   
100.
Existing antidepressants seem to have an onset time of several weeks. However, newly found depression-related receptors and pathways may enlighten us to find more rapid-onset antidepressants, in which ketamine is one of the most potential antidepressants. By intranasal administration, drugs can be directly delivered to the brain via olfactory nerve route, which is proved to be suitable for some antidepressants. Well-designed rapid-onset antidepressants are the urgent requirements of the patients with depression. Intranasal administration, as a potential strategy to deliver antidepressants to brain, can improve drug efficacy and largely shorten the onset time. In this article, we sorted out some new formulation approaches in treating depression with different mechanisms and pathways compared with traditional treating strategies, along with new findings in clinical studies, proving that the combination of rapid-onset antidepressants with intranasal delivery will lead a new trend in treating depression.  相似文献   
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