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101.
T. Yoshimaru Y. Suzuki T. Matsui† K. Yamashita† T. Ochiai‡ M. Yamaki† K. Shimizu 《Clinical and experimental allergy》2002,32(4):612-618
BACKGROUND: Previous studies have shown that rat peritoneal mast cells and mast cell model rat basophilic leukaemia (RBL-2H3) cells generate intracellular reactive oxygen species (ROS) in response to antigen challenge. However, the physiological significance of the burst of ROS is poorly understood. OBJECTIVE: The present study was undertaken to investigate the role of superoxide anion in mediator release in rat and human cell systems. METHODS: RBL-2H3 cells were directly stimulated with anti-rat FcepsilonRI alpha-subunit monoclonal antibody (mAb). For the analysis of human cell system, leucocytes were isolated by dextran sedimentation from healthy volunteers or from patients, and challenged either with anti-human FcepsilonRI mAb or with the relevant antigens. Superoxide generation was determined by chemiluminescence-based methods. The releases of histamine and leukotrienes (LT)s were determined by enzyme-linked immunosorben assay (ELISA). RESULTS: Cross-linking of FcepsilonRI on RBL-2H3 cells or on human leucocytes from healthy donors by the anti-FcepsilonRI mAb resulted in a rapid generation of superoxide anion, as determined by chemiluminescence using superoxide-specific probes. Similarly, leucocytes from patients generated superoxide anion in response to the challenge with the relevant allergen but not with the irrelevant allergen. Furthermore, diphenyleneiodonium (DPI), a well-known inhibitor of flavoenzymes suppressed the superoxide generation and the release of histamine and LTC4 induced by the anti-FcepsilonRI mAb or by allergen in parallel. CONCLUSION: These results indicate that both RBL-2H3 cells and human basophils generate superoxide anion upon FcepsilonRI cross-linking either by antibody or by allergen challenge and that blockade of the generation prevents the release of allergic mediators. The findings strongly support the role of superoxide generation in the activation of mast cells and basophils under both physiological and pathological conditions. The findings suggest that drugs regulating the superoxide generation have potential therapeutic use for allergic disorders. 相似文献
102.
目的:观察思他宁对人胰腺癌细胞ASPC-1的生长作用.方法:细胞培养,分别加入不同浓度的思他宁.应用MTT法来观察细胞增殖程度;放免法测定细胞内cAMP含量;荧光法测定[Ca2 ]i.结果:不同浓度的思他宁(10-11~10-6mol/L)均能有效地抑制ASPC-1的生长,能抑制ASPC-1细胞内cAMP生成和细胞内钙离子水平,cAMP生成量和细胞内钙离子水平与思他宁浓度呈负相关.结论:思他宁能抑制ASPC-1细胞的生长,经过特异性受体调节. 相似文献
103.
松花粉对人肺成纤维细胞增殖活性影响的实验研究 总被引:1,自引:0,他引:1
目的 :研究松花粉对人肺成纤维细胞增殖的影响 ,探讨中药松花粉可能的作用机理。方法 :松花粉作用于人肺成纤维细胞不同时间后观察细胞生长速度 ,应用台盼蓝对细胞进行染色 ,测定细胞死亡率。松花粉浓度分别为 10 0、2 0 0、40 0、80 0mg·L-1,以未经松花粉处理的细胞为对照。结果 :松花粉作用于人肺成纤维细胞能够明显促进细胞群体倍增水平 ,降低死亡细胞数目 ,且呈剂量依赖关系。结论 :松花粉可通过促进细胞生长而影响细胞增殖。 相似文献
104.
S Lalith Talagala Frank Q Ye Patrick J Ledden Scott Chesnick 《Magnetic resonance in medicine》2004,52(1):131-140
A variety of continuous and pulsed arterial spin labeling (ASL) perfusion MRI techniques have been demonstrated in recent years. One of the reasons these methods are still not routinely used is the limited extent of the imaging region. Of the ASL methods proposed to date, continuous ASL (CASL) with a separate labeling coil is particularly attractive for whole-brain studies at high fields. This approach can provide an increased signal-to-noise ratio (SNR) in perfusion images because there are no magnetization transfer (MT) effects, and lessen concerns regarding RF power deposition at high field because it uses a local labeling coil. In this work, we demonstrate CASL whole-brain quantitative perfusion imaging at 3.0 T using a combination of strategies: 3D volume acquisition, background tissue signal suppression, and a separate labeling coil. The results show that this approach can be used to acquire perfusion images in all brain regions with good sensitivity. Further, it is shown that the method can be performed safely on humans without exceeding the current RF power deposition limits. The current method can be extended to higher fields, and further improved by the use of multiple receiver coils and parallel imaging techniques to reduce scan time or provide increased resolution. 相似文献
105.
在20名正常人前臂内侧涂以4种以清凉油为基质含不同浓度地塞米松(0.1、0.05、0.025、0.0125%)的皮炎速灵油膏,并以清凉油作阴性对照,地塞米松软膏作阳性对照。采用改良的Mckenzie和Stoughton法,将六种药剂涂于同一个体,以消除个体间反应差异。涂药后3h拭去药物,再经2、3、4、5、7、9及21h进行观察并打分,在双盲条件下根据用药部位发白情况由3名评估者对每名受试者独立打分,应用Wilcoxon等经典秩和试验法进行统计分析,结果显示清凉油和所有含地塞米松的制剂之间存在着非常显著的差异,并对受试者反应和评估者打分的变异系数进行了计算。我们的体会是血管收缩试验在黄种人也是可行的,而这种打分系统只要提供足够数量的受试者,特别适宜于应用Wilcoxon等统计方法。 相似文献
106.
本文应用HPV-PCR技术和DNA杂交技术对76例宫颈鳞癌标本进行了HPV-DNA的研究,发现HPV-DNA存在率为90.79%(69/76),主要类型为HPV16和18。多酶切SouthernBlot杂交证实在宫颈癌中92.56%的HPV-DNA发生变异,说明HPV-DNA的基因变异与其致癌作用密切相关。PCR结果证实HPV-E6片段在宫颈癌组织中常可出现,推测可能是致癌的关键片段之一。因此,检测宫颈癌组织中HPV-DNA的完整性、关键基因片段的存在与否,可能对于病变恶变的预测有一定的意义 相似文献
107.
报告1100名35岁以上农民冠心病患病率及易患因素的调查结果。全组中检出冠心病15例,其中陈旧心肌梗塞3例、心绞痛7例、心律失常及不典型心绞痛伴有心电图缺血型改变者5例,冠心病现患率为1.36%。另有单纯ST-T 缺血型改变84例,各种严重心律失常36例,未计入冠心病现患率之内.经单变量线性相关及多变量Logistic 函数分析结果,选出有意义的冠心病易患因素有甘油三酯、年龄及收缩期血压增高,以及血浆高密度脂蛋白胆固醇的降低。 相似文献
108.
Nucleic acid spot hybridization with nonradioactive labeled probes in screening for human papillomavirus DNA sequences 总被引:1,自引:0,他引:1
We examined 161 human tissue samples using the spot hybridization technique with nonradioactive labeled DNA probes of human papillomavirus (HPV). Whole cells were spotted on nitrocellulose filters; DNA of the cells was denatured and fixed to the filter. Then the DNA spots were hybridized to nonradioactive labeled DNA and monitored by a sandwich immunoenzymatic reaction. This technique is simple, sensitive, specific, requires no special equipment, and can be used in clinical settings. HPV DNA was found in 92% of samples in which, on the basis of histologic and colposcopic criteria, its presence was suspected, as well as in 31 samples where it was not suspected. 相似文献
109.
报告2687例血清甲状腺球蛋白抗体和甲状腺微粒体抗体的放射免疫测定结果,九类病人的抗体阳性率如下:甲状腺正常病人12.6(30/239)、孤立甲状腺结节16.9%(62/383)、弥漫性甲状腺肿35.4%(226/638)、多结节甲状腺肿54.7%(104/190)、甲亢未治疗77.7%(404/520)、甲亢治疗中67.2%(218/345)甲亢临床已治愈60.3(102/169),原发性甲减80.8%(118/146)、亚急性甲状腺炎35.1%(20/57)。各种甲状腺疾病的总阳性率为51.2%(1254/2448)。对甲状腺自抗体阳性在甲状腺疾病的诊断、治疗、和预后判断上的意义进行了讨论。 相似文献
110.
Two strains of T. rubrum and one strain of T. mentagrophytes were inoculated into human skin grafted onto BALB/c nude mice by the needle puncture method. Infection was established in 1 of the 10 animals inoculated with fluffy colony type T. rubrum, 2 of the 10 animals inoculated with powdery colony type T. rubrum, and 7 of the 10 animals inoculated with granular colony type T. mentagrophytes, suggesting that the skin grafts are infectible by anthropophilic and zoophilic strains of dermatophytes. T. rubrum infection continued for a maximum of 9 weeks and T. mentagrophytes infection for more than 11 weeks. In the animals inoculated with T. mentagrophytes, fungal elements were localized in the stratum corneum of the human skin grafts. In the acute stage, microabscesses consisting of neutrophils were observed under the stratum corneum in contact with fungal elements; in the chronic stage, epidermal thickening and infiltration, mainly consisting of histiocytes and a smaller number of lymphocytes, was noted in the upper and middle dermis. Ultrastructural findings from the parasites were similar to those of dermatophytosis in man. This experimental system should be useful as a model of chronic dermatophyte infection in the human skin. 相似文献