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51.
An adequate child hygiene program includes activities directed toward
maintaining the health of l;,oth mother and child from the prenatal period
to the end of adolesence. In China, for convenience in administration, the
"maternity ancl child heah:h" work extends onIy through the pre-school period.
while school health work is considered a separalie though related field. 相似文献
52.
Reactive oxygen species (ROS) are products of normal cellular metabolism and are known to act as second messengers. Under physiological conditions, ROS participate in maintenance of cellular 'redox homeostasis' in order to protect cells against oxidative stress through various redox-regulatory mechanisms. Overproduction of ROS, most frequently due to excessive stimulation of either reduced nicotinamide adenine dinucleotide phosphate by cytokines or the mitochondrial electron transport chain and xanthine oxidase, results in oxidative stress. Oxidative stress is a deleterious process that leads to lung damage and consequently to various disease states. Knowledge of the mechanisms of ROS regulation could lead to the pharmacological manipulation of antioxidants in lung inflammation and injury. 相似文献
53.
Chronic wounds, particularly venous ulcerations, are notoriously difficult to heal. Because current therapies are variable in their ability to induce complete healing, there remains a need to develop adjunctive treatments that can improve or accelerate the healing process. The use of low-energy lasers to stimulate wound healing has been pursued over many decades in studies of varying quality. This form of treatment has had high appeal due to its novelty, relative ease, and low morbidity profile. The authors reviewed the available published literature on low-level laser technology in an attempt to provide cumulative insight on the effect of this treatment for wound healing. 相似文献
54.
电磁噪声阻断极低频磁场对细胞缝隙连接功能的抑制效应 总被引:7,自引:3,他引:4
目的 探讨电磁噪声对 5 0Hz磁场诱导的细胞缝隙连接通讯功能 (GJIC)抑制的干预作用。方法 小鼠成纤维细胞 (NIH 3T3)受 5 0Hz 0 .4mT极低频磁场或磁场加同等强度的电磁噪声联合作用 2 4h后 ,在激光共聚焦显微镜下 ,采用荧光光漂白后恢复技术 (FRAP)测定细胞的GJIC功能。结果 0 .4mT磁场单独作用明显抑制细胞的GJIC ,其荧光恢复率为 2 7.6 7%± 5 .12 % ,与对照组(45 .5 7%± 9.72 % )相比 ,差异有显著性 (P <0 .0 1) ;而磁场与电磁噪声联合作用 (5 2 .6 1%± 8.30 % )明显拮抗磁场对GJIC的抑制作用 ,与 0 .4mT磁场组的差异有显著性 (P <0 .0 1) ,并与对照组的差异无显著性 (P >0 .0 5 )。结论 电磁噪声对极低频磁场诱导的GJIC的抑制具有阻断作用 相似文献
55.
Background and objective: Activated bronchial epithelial cells exert considerable potential to maintain a microenvironment in the airway wall that promotes airway inflammation and remodelling. Cysteinyl leucotrienes (CysLT) and transforming growth factor‐β1 (TGF‐β1) are both increased in asthmatic airways and may influence the pathophysiology of disease. However, the consequences of activation of bronchial epithelial cells by these mediators are not fully understood. A proteomic‐based approach was used to characterize the inflammatory pathways in bronchial epithelial cells after stimulation with CysLT and TGF‐β1. Methods: Human bronchial epithelial cells (BEAS‐2B) were stimulated with 1 ng/mL TGF‐β1 and 50 nmol/L leucotriene E4 (LTE4) for 48 h and whole‐cell lysates were subjected to two‐dimensional gel electrophoresis. Proteins showing statistically significant differential expression were identified by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry and database searching. Results: Stimulation with LTE4 increased the expression of three proteins and five proteins showed decreased expression. Of the latter group, two were definitively identified as heat shock protein (Hsp90α) and stress‐70 protein. Hsp90α forms a heterocomplex with the glucocorticoid receptor (GR) and a significant decrease in GR following LTE4 stimulation was confirmed. TGF‐β1 downregulated 18 intracellular proteins, including lamin A/C, glyceraldehyde‐3‐phosphate dehydrogenase, protein DJ‐1, voltage‐dependent calcium channel gamma‐7 subunit, heterogeneous nuclear ribonucleoprotein A2/B1 and stress‐70 protein. Conclusions: The current findings suggest that by downregulating GR and Hsp90α, CysLT may interfere with the action of glucocorticoids. Overall, the results confirm the complex role of bronchial epithelium in aspects of airway inflammation and remodelling. 相似文献
56.
Streptococcus pneumoniae (pneumococcus) remains a common cause of disease and death throughout the world. Despite considerable research into various aspects of this infection, there still remain a number of unresolved issues, as well as considerable ongoing controversies, particularly with regard to its optimal management. Among the risk factors for pneumococcal pneumonia, cigarette smoking has been shown to play a major role, more recently among HIV-infected individuals. Considerable recent research has focused on determining the role of the various protein virulence factors in disease pathogenesis. Among the ongoing controversies has been an appreciation of the true impact of antimicrobial resistance on the outcome of pneumococcal infections, as well an understanding of the role of combination antibiotic therapy in the more severely ill hospitalized cases. An important advance in the prevention of pneumococcal infections has been the introduction of the pneumococcal protein conjugate vaccine. 相似文献
57.
58.
Child maltreatment and the responsibility of heath care professionals to assist in prevention and diagnosis is currently center stage in the United Kingdom. This subject has a very large literature base. Anesthetists were one of the first groups to have specific guidance on this subject, and key competencies are now part of the core curriculum for our trainees. This article seeks to briefly define maltreatment and provide statistics that outline the scale of the problem, and includes discussion of risk factors and recognition. We have focused on physical abuse and have provided a separate section on abusive head trauma, which is of particular importance to anesthetists. We also discuss the process of management, with some detail around Child Death Review procedures. 相似文献
59.
极低频磁场对细胞色素氧化酶亚基1基因转录水平的影响 总被引:3,自引:1,他引:2
目的 克隆和鉴定本研究室经DD法在Daudi细胞中筛选到的一个极低频磁场的特异反应基因 (MF 1) ,并在多种磁场敏感细胞中证实该基因反应的普遍性 ,为揭示磁场所致生物学效应的作用机制提供实验依据。方法 克隆、序列分析MF 1片段 ;选择HL 6 0、L12 10和中国仓鼠肺成纤维细胞 (CHL)等细胞 ,用Northern技术观察该基因在不同条件的磁场辐照 (5 0Hz磁场 ,磁通密度分别是 0 .1mT和 0 .8mT ,辐照时间分别是 2 0min和 2 4h)后该基因转录水平的变化。结果 克隆测序及与GeneBank同源性比较表明 ,MF 1序列与细胞色素氧化酶亚基 1基因 (CO1)有 10 0 %同源性。HL 6 0、L12 10和CHL等细胞在 0 .1mT、0 .8mT磁场辐照 2 0min后 ,CO1转录水平 (分别为 0 .38± 0 .12、0 .37± 0 .0 4 )均比对照组 (0 .5 8± 0 .12 )下降 ,差异有显著性 (P <0 .0 5 ) ;辐照 2 4h后 ,3种细胞该基因转录水平 (分别为 0 .4 6± 0 .0 9、0 .4 5± 0 .0 9)亦比对照组 (0 .6 5± 0 .0 6 )下降 ,差异有显著性 (P <0 .0 5 )。结论 CO1是磁场辐照密切相关的反应基因之一。磁场可能通过影响CO1的转录水平来影响细胞色素氧化酶的活力 ,从而影响多种生物学效应 相似文献
60.
Wan C. TAN Paul SEALE Mary IP Young-Soo SHIM Chi-Huei CHIANG Tze-Pin NG John ABISHEGANADAN Suchai CHAROENRATANAKUL Teresita DeGUIA Aziah MAHAYIDDIN Hardiato MANGUNNEGORO Yong-Jian XU Nan-Shan ZHONG 《Respirology (Carlton, Vic.)》2009,14(1):90-97
Background and objective: The growing burden of COPD in the Asia‐Pacific region supports the need for more intensive research and analysis of the epidemiology of COPD to raise awareness of the disease and its causes, to ensure the development of effective national health policies and to facilitate equitable deployment of finite health‐care resources in the prevention and management of COPD. This study estimated and compared COPD mortality and hospital morbidity rates and trends in these rates over time across countries and regions of Asia‐Pacific. Methods: Data consistent with standard definitions of COPD (ICD‐9/ICD‐10) for the period 1991–2004 were obtained from national health statistics agencies. For countries/regions with complete national mortality and hospitalization data (Australia, Pacific Canada (British Columbia, Hong Kong, South Korea and Taiwan), annual age‐standardized mortality and hospitalization rates were calculated for men and women aged ≥ 40 years. Negative binomial regression modelling was used to estimate rate ratios for country/region, gender and age differences and general trends over time. Results: Mortality rates per 10 000 population ranged 6.4–9.2 in men, 2.1–3.5 in women and 3.7–5.3 overall in 2003. Corresponding ranges for morbidity were 32.6–334.7, 21.2–129 and 28.1–207.3 per 10 000. Trend analysis of data since 1997 produced annual percentage changes in mortality versus hospitalization of ?4.4% versus ?0.7% in Australia, ?3.6% versus 7.5% in Pacific Canada (British Columbia), ?7.15% versus ?5.6% in Hong Kong and ?2.9% versus ?4.2% in Taiwan. Conclusions: In Asia‐Pacific, overall mortality and morbidity rates are high and trends in mortality and morbidity vary between countries/regions. Differences in rates and trends for men and women most likely reflect the different trends in historical and prevalent smoking profiles for COPD in the different countries and regions. 相似文献