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51.
Summary The cardiovascular effects at rest and during exercise and 1- and 2-adrenoceptor occupancy following a single dose of 1200 mg celiprolol p. o. were investigated in 8 healthy subjects with or without pretreatment with a single dose of 20 mg bisoprolol p. o., using a place-bo-controlled, 2-way cross-over design.The ergometric responses of heart rate (HR) and systolic blood pressure (SBP) after celiprolol were reduced to a similar extent as after bisoprolol, but the cardiovascular function at rest was affected in a different way: there was a rise in HR, clear enhancement of cardiac systolic performance, and a considerable drop in the estimated total peripheral vascular resistance, associated with median 1-RRA and 2-RRA occupancies of 88 and 34%, respectively. The cardiovascular effects of celiprolol were not affected by pretreatment with bisoprolol. Celiprolol thus binds extensively to 1-adrenoceptors, moderately to 2-adrenoceptors, acts as 1-adrenergic antagonist (exemplified by the ergometric effects) but has vasodilator, positive chronotropic and cardiac systolic performance enhancing properties, which do not involve either direct or indirect 1-adrenergic agonism, but which might reflect 2-adrenergic agonism.  相似文献   
52.
为建立一种检测活细胞数的方法,作者采用三磷酸腺苷(ATP)生物荧光液闪测定法检测小鼠纤维瘤细胞株L929.ATP标准曲线工作范围为10 -9~10-5mol/ml,相关系数r=0.9963(P<0.001);当活细胞数在3×1 02~106个/ml时与发光计数值有良好的线性关系,r=0.9922(P<0.001),变异系数 CV = 1%~3%.用ATP生物荧光液闪测定法检测活细胞数灵敏、简便、准确、重复性好,用液闪计数仪即可完成测定,有较大的实用价值.  相似文献   
53.
目的 研究俄歇电子发射体67Ga-EDTMP对人骨肉瘤细胞株 (HOS - 86 0 3)的辐射效应 ,探讨67Ga作为原发肿瘤和骨转移癌内照射治疗核素的可能性。方法 用成集落实验和透射电镜研究受照细胞的形态变化。结果 发现67Ga-EDTMP对肿瘤细胞有明显的杀伤和抑制增殖作用 ,并随剂量的加大 ,抑制效率增加 ;倒置显微镜下细胞集落数量减少 ,集落偏小 ,细胞稀疏。电镜下胞浆中空泡形成 ,细胞溶解、坏死 ,细胞核固缩 ,出现典型的细胞凋亡改变 ,形成凋亡小体。结论 67Ga可能是一种有前途的骨肉瘤和骨转移癌的放射性治疗核素  相似文献   
54.
胆汁泡蛋白ELISA检测法的建立与初步临床应用   总被引:1,自引:0,他引:1  
目的 建立胆汁泡蛋白快速检测法,筛选有效的胆石症防治手段。方法 获取33.5kd胆汁泡蛋白,通过微量抗原免疫法获得高效价抗体,建立ELISA标准曲线;并应用ELISA法测定正常人、胆石症患者胆汁和血清中泡蛋白含量,同时观察不同溶石防药和利胆冲剂、胆酸钠等对泡蛋白的影响。结果 建立了ELISA标准曲线,其曲线方程为Y=0.035X(r=0.99);正常人胆汁和血清中33.5kd泡蛋白含量都明显较胆固  相似文献   
55.
慢性特发性荨麻疹患者血清组胺释放活性的检测   总被引:7,自引:0,他引:7  
目的 检测慢性特发性荨麻疹患者血中组胺释放活性。方法 自身血清皮肤试验和嗜好性粒细胞组胺释放试验。结果 自身血清皮肤试验和嗜碱性组胺释放试验的阳性率分别为37.5%和43.75%。结论部分慢性特发性荨麻疹患者血中组胺释放活性增高,揭示该类病人具有特殊的肥大细胞和嗜碱性粒细胞激活机制,很可能与自身免疫有关。  相似文献   
56.
不同实体瘤体外药敏试验的可行性研究   总被引:1,自引:0,他引:1  
目的:研究体外药敏试验用于不同原代培养肿瘤细胞的可行性,方法:采用MTT比色分析法,结果:非小细胞肺癌,食管癌,贲门癌对乐铂均较敏感,不同病理类型和同一类型的不同个体对乐铂的敏感性差异较大,且其抑制作 病理类型无密切关系。结论:MTTI地操作简便,快捷,敏感,可应用于实体瘤临床个体化的药敏检测。  相似文献   
57.
MTT显色反应实验条件分析   总被引:11,自引:0,他引:11  
目的 :检验分析MTT实验方法本底高、灵敏度低、稳定性差的影响因素 ,改进实验条件提高灵敏度和稳定性 ,降低本底。方法 :用MTT比色方法 ,细胞毒试验及细胞增殖实验 ,分析比较不同条件下MTT显色反应的性能特点。结果 :比较了 13种溶剂对Formazan的溶解性能。分析检验了琥珀酸脱氢酶在细胞上的分布特点、pH值对MTT反应体系的影响、酚红和牛血清对检验结果的影响 ,提出相应对策。检测了MTT反应时间曲线和细胞活力曲线。分析了改进后的MTT实验方法的灵敏度和稳定性。结论 :以MTT为底物的酶在细胞代谢中主要分布在细胞膜表面。MTT反应体系的pH值为 6 7,比较好的Formazan溶剂是正丙醇、异丙醇和乙二醇乙醚。去掉细胞培养上清 ,检测细胞上的酶 ,用溶剂使蛋白质变性 ,经沉淀去掉蛋白质影响 ,能使MTT实验方法的本底降低 ,灵敏度提高。通常情况下该方法检测K 5 62细胞和人淋巴细胞的灵敏度分别为 10 0 0和 10 0 0 0个细胞左右。  相似文献   
58.
Cultivated T24 cells derived from a human bladder cancer were inoculated into the chorioallantoic membrane vein of chick embryos. Hyperthermic treatment was performed following injection of anticancer agents 3 days after the inoculation of the T24 cells. DNA samples were obtained from the livers of the chick embryos, and the polymerase chain reaction technique was used to amplify a DNA fragment specific to the human -globin gene. The Southern hybridization method was used to evaluate the inhibitory effects of anticancer agents in combination with/without hyperthermia on T24 cells metastasized to the liver. The hyperthermia exerted an inhibitory effect on the growth of the T24 cells in the livers of the chick embryos, and this was dependent on the thermal dose. The antitumor effects of hyperthermia performed at 42.5° C for 20 min and at 43.0° C for 10 min were evidenced by 69.2% an 82.0% inhibition of the growth of the metastasized T24 cells, respectively, as compared with the growth of untreated T24 cell. Hyperthermia performed at 42.5° C for 10 min alone produced 26.7% tumor growth inhibition, and these conditions for hyperthermia were subsequently used as a criterion for evaluating the effects of its combination with various anticancer agents. Adriamycin (20 g/egg) alone, mitomycin C (10 g/egg) alone, carboplatin (10 g/egg) alone, and cisplatin (10 g/egg) alone produced 13.5%, 58.9%, 27.3%, and 29.1% tumor growth inhibition, respectively. Adriamycin and mitomycin C applied in combination with hyperthermia showed additive inhibitory effects on the growth of the metastasized T24 cells in this chick embryo model.  相似文献   
59.
We studied invasion-related adhesion events in vitro using three squamous carcinoma cell lines (HSC-3, poorly differentiated type; OSC-19, well-differentiated type; and KB cells, undifferentiated type). An in vitro invasion assay through matrigel in the transwell chamber revealed that HSC-3 cells were most invasive, OSC-19 cells moderately invasive and KB cells least invasive. Inhibition assay of invasion using synthetic peptides RGD, RGDV, RGDS, RGDT, IKVAV and YIGSR, showed that invasion of the three cell lines was significantly inhibited by RGDV. There were other peptides that inhibited invasion significantly including IKVAV for HSC-3, and RGDS and YIGSR for OSC-19. HSC-3 cells and OSC-19 cells adhered to fibronectin, laminin, vitronectin, and type IV collagen, and KB cells did not adhere to laminin but did to fibronectin, vitronectin and collagen type IV. Pretreatment of cells with RGDV peptide in the attachment assay reduced the ability of these cells to bind to vitronectin and fibronectin more efficiently than pretreatment with RGDS. Anti-v antibodies inhibited adhesion of HSC-3, OSC-19 and KB cells to vitronectin, but anti-1 antibodies did not inhibit adhesion. Immunofluorescent microscopic examinations showed that all cell lines were positive for anti-5 and anti-v antibodies, and only HSC-3 cells were positive for anti-3 antibody. 51 was not clearly demonstrated in any of the cell lines. RGDV was the most effective inhibitor of squamous cell carcinoma invasion among the synthetic oligopeptides used in this experiment, and it is suggested that it affects v3-and/or v5-mediated carcinoma cell invasion.Abbreviations BSA bovine serum albumin - MEM Eagle's minimal essential medium - MTT 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide - PBS phosphatebuffered saline - FITC fluorescein isothiocyanate This work supported in part by a grant from the Osaka Cancer Research Foundation  相似文献   
60.
Benzene and five of its known metabolites—muconic acid, hydroquinone, catechol, p-benzoquinone, and benzentriol—were examined for DNA damage in human lymphocytes using the alkaline Comet assay, and conditions were optimised to determine responses. Metabolic activation (S-9 mix) was included in the assay for varying times to try to enhance effects. In addition, the effects of catalase were investigated as it is known to be present in S-9 mix reducing oxidative damage, and some benzene metabolites are known to react through oxygen radical mechanisms. Effects were also examined in cycling cells to determine whether they were more sensitive to damage then noncycling cells. Comets were measured either by eye or by image analysis. Data have been presented according to length of treatments. When Comets were measured by eye after treatment with hydrogen peroxide (H2O2), the positive control, and each compound for 0.5 hr, only H lymphocytes. When comets were measured by image analysis, a 0.5-hr treatment with H2O2 and benzenetriol and catechol confirmed results analysed by eye, with S-9 mix greatly reducing responses. When treatments were increased to 1 hr in the presence and absence of S-9 mix, benzene at a 5-fold increased dose produced a significant positive response but not at the lower dose. When treatment times were increased to 2 and 4 hr, doses were also increased, and muconic acid, hydroquinone, catechol, and benzoquinone in the presence of S-9 mix showed positive time and dose-related responses, and at the highest dose of benzoquinone the morphology of the nucleus was affected. Effects tended to become more pronounced at high doses and after longer exposures, although this was not always consistent from experiment to experiment. In conclusion, benzene and all metabolites investigated gave positive responses. Where altered responses were observed, they were significantly different from the corresponding controls. © 1995 Wiley-Liss, Inc.  相似文献   
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