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31.

Background

Migration is a major challenge to tuberculosis (TB) control worldwide. TB treatment requires multiple drugs for at least six months. Some TB patients default before completing their treatment regimen, which can lead to ongoing infectiousness and drug resistance.

Methods

We conducted a retrospective analysis of 29,943 active TB cases among urban migrants that were reported between 2000 to 2008 in Shanghai, China. We used logistic regression models to identify factors independently associated with treatment defaults in TB patients among urban migrants during 2005-2008.

Results

Fifty-two percent of the total TB patients reported in Shanghai during the study period were among urban migrants. Three factors increased the odds of a treatment default: case management using self-administered therapy (OR, 5.84, 95% CI, 3.14-10.86, p<0.0005), being a retreatment case (OR, 1.47, 95% CI, 1.25-1.71, p<0.0005), and age >60 years old (OR, 1.33, 95% CI, 1.05-1.67, p=0.017). The presence of a cavity in the initial chest radiograph decreased the odds for a treatment default (OR, 0.87, 95% CI, 0.77-0.97, p=0.015), as did migration from central China (OR, 0.85, 95% CI, 0.73-0.99, p=0.042), case management by family members (OR, 0.73, 95% CI 0.66-0.81, p<0.0005), and the combination of case detection by a required physical exam and case management by health care staff (OR, 0.64, 95% CI, 0.45-0.93, p=0.019).

Conclusion

Among TB patients who were urban migrants in Shanghai, case management using self-administered therapy was the strongest modifiable risk factor that was independently associated with treatment defaults. Interventions that target retreated TB cases could also reduce treatment defaults among urban migrants. Health departments should develop effective measures to prevent treatment defaults among urban migrants, to ensure completion of therapy among urban migrants who move between cities and provinces, and to improve reporting of treatment outcomes.  相似文献   
32.
We sought to determine whether the extrapulmonary origin of fibroblasts derived from bone marrow (BM) progenitor cells is essential to lung fibrosis in bronchopulmonary dysplasia (BPD). Neonate mice were durably engrafted with BM isolated from transgenic reporter mice that expressed green fluorescent protein (GFP). Such chimera mice were subjected to 60% O(2) exposure for 14 days. A large number of fibroblast-specific protein-1 (FSP1) and GFP-positive fibroblasts were identified in active fibrotic lesions. More surprisingly, however, FSP1(+) fibroblasts also arose in considerable numbers from BM-derived alveolar type II cells (AT2) through epithelial-mesenchymal transition (EMT) during lung fibrogenesis. Cultured lung fibroblasts could express the CXC chemokine receptor (CXCR4) and responded chemotactically to their cognate ligand, chemokine (C-X-C motif) ligand 12 (CXCL12), which were elevated in the serum of BPD mice. These data suggest that lung fibroblasts in BPD fibrosis could variably arise from BM progenitor cells. This finding, which suggests the pathophysiological process of fibrosis, could contribute to a therapy for BPD that is characterized by extensive interstitial fibrosis.  相似文献   
33.
In this contribution, a simple, rapid, colorimeteric and selective assay for lysine was achieved by a controllable end-to-end assembly of gold nanorods (AuNRs) in the presence of Eu(3+) and lysine. This one-pot end-to-end assembly of 11-mercaptoundecanoic acid (MUA) modified AuNRs was occurred in Britton-Robinson buffer of pH 6.0, which involves the coordination binding between Eu(3+) and COO(-) groups as well as the electrostatic interaction of the COO(-) groups of MUA with the -NH(3)(+) group of lysine. As monitored by absorption spectra, scanning electron microscopic (SEM) images and dynamic light scattering (DLS) measurement, the end-to-end chain assembly results in large red-shift in the longitudinal plasmon resonance absorption (LPRA), giving red-to-blue color change of AuNRs. Importantly, it was found that the red-shift of LPRA is linearly proportional to the concentrations of lysine in the range of 5.0×10(-6)-1.0×10(-3)M with the limit of detection (LOD) being 1.6×10(-6)M (3σ/k). This red-shift of LPRA is highly selective, making it possible to develop a rapid, selective and visual assay for lysine in food samples.  相似文献   
34.
Low-cost, robust, and user-friendly diagnostic capabilities at the point-of-care (POC) are critical for treating infectious diseases and preventing their spread in developing countries. Recent advances in micro- and nanoscale technologies have enabled the merger of optical and fluidic technologies (optofluidics) paving the way for cost-effective lensless imaging and diagnosis for POC testing in resource-limited settings. Applications of the emerging lensless imaging technologies include detecting and counting cells of interest, which allows rapid and affordable diagnostic decisions. This review presents the advances in lensless imaging and diagnostic systems, and their potential clinical applications in developing countries. The emerging technologies are reviewed from a POC perspective considering cost effectiveness, portability, sensitivity, throughput and ease of use for resource-limited settings.  相似文献   
35.
Cypripediumlichiangense S.C.Chen & P.J.Cribb (Orchidaceae),endemic to China,is an endangered species according to I UCN Red List criteria (IUCN,2001:I UCN Red List Categories and Criteria,Version  相似文献   
36.
An integro-differential equation is proposed to model a general relapse phenomenon in infectious diseases including herpes. The basic reproduction number R(0) for the model is identified and the threshold property of R(0) established. For the case of a constant relapse period (giving a delay differential equation), this is achieved by conducting a linear stability analysis of the model, and employing the Lyapunov-Razumikhin technique and monotone dynamical systems theory for global results. Numerical simulations, with parameters relevant for herpes, are presented to complement the theoretical results, and no evidence of sustained oscillatory solutions is found.  相似文献   
37.
Reactive oxygen species (ROS) modulate aging and aging-related diseases. Dietary composition is critical in modulating lifespan. However, how ROS modulate dietary effects on lifespan remains poorly understood. Superoxide dismutase 1 (SOD1) is a major cytosolic enzyme responsible for scavenging superoxides. Here we investigated the role of SOD1 in lifespan modulation by diet in Drosophila. We found that a high sugar-low protein (HS-LP) diet or low-calorie diet with low-sugar content, representing protein restriction, increased lifespan but not resistance to acute oxidative stress in wild-type flies, relative to a standard base diet. A low sugar-high protein diet had an opposite effect. Our genetic analysis indicated that SOD1 overexpression or dfoxo deletion did not alter lifespan patterns of flies responding to diets. However, sod1 reduction blunted lifespan extension by the HS-LP diet but not the low-calorie diet. HS-LP and low-calorie diets both reduced target of rapamycin (TOR) signaling and only the HS-LP diet increased oxidative damage. sod1 knockdown did not affect phosphorylation of S6 kinase, suggesting that SOD1 acts in parallel with or downstream of TOR signaling. Surprisingly, rapamycin decreased lifespan in sod1 mutant but not wild-type males fed the standard, HS-LP, and low-calorie diets, whereas antioxidant N-acetylcysteine only increased lifespan in sod1 mutant males fed the HS-LP diet, when compared to diet-matched controls. Our findings suggest that SOD1 is required for lifespan extension by protein restriction only when dietary sugar is high and support the context-dependent role of ROS in aging and caution the use of rapamycin and antioxidants in aging interventions.  相似文献   
38.
唐剑  李峥 《蛇志》2015,(2):123-125
目的探讨颅脑损伤后血清S-100B蛋白、神经元特异性烯醇化酶(NSE)水平变化及其在损伤程度的临床意义。方法采用酶联免疫测定法检测90例颅脑损伤患者入院时及入院后6、12、24h和3、7天血清S-100B蛋白、NSE水平,并分析其与颅脑损伤严重程度的关系。同时选择30例健康体检者作为对照组进行比较分析。结果颅脑损伤后血清S-100B蛋白、NSE水平较对照组明显升高(P0.05或P0.01);重型组患者的血清S-100B蛋白和NSE水平明显高于轻、中型组患者(P0.05或P0.01);动态检测结果显示,血清S-100B蛋白在伤后12h达峰值(P0.05),NSE含量在伤后24h达峰值(P0.05),然后缓慢下降。GCS评分与S-100B、NSE浓度呈负相关(分别为r=-0.814,P0.01;r=-0.726,P0.05)。结论颅脑损伤后血清S-100B蛋白、NSE水平升高,其与脑损伤程度有较好的相关性,2种标记物水平对颅脑损伤程度有较高的评估价值。  相似文献   
39.
40.
桉树幼苗对难溶性磷的吸收及其根系对低磷胁迫的响应   总被引:2,自引:0,他引:2  
以‘广林9号’桉树幼苗为试验材料,采用水培和土培试验方法研究了桉树幼苗对难溶性磷酸盐的吸收及其在低磷胁迫下的根构型和根系的生理反应,以揭示桉树高效吸收磷素的机制。结果显示:(1)桉树幼苗在含磷酸铝的缺磷培养液中吸收的磷达4.24mg/株,与供应水溶性磷和磷酸钙处理的相当。(2)土壤缺磷或仅在上土层(0~20cm)施磷肥处理均有利于桉树幼苗浅层根的分布,使根表面积及根数在上土层与下层(20~40cm)比值明显增高。(3)桉树幼苗根尖的H+-ATPase活性在缺磷处理15d后显著提高,其根尖周围的溴甲酚紫指示剂变黄,根基环境明显酸化;根尖分泌的酸性磷酸酶活性在低磷胁迫也显著提升,且随着处理时间(10、15、20d)的延长而进一步提高;铝和低磷胁迫能明显诱导桉树根系分泌草酸,其分泌量显著高于对照和缺磷处理。研究结果表明,桉树幼苗具有较强的难溶性磷吸收能力,而在缺磷及磷铝胁迫下根系的浅层化、根尖酸化及根分泌的酸性磷酸酶及草酸量增加可能是桉树幼苗适应酸性土壤铝毒和缺磷环境的重要机制。  相似文献   
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