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71.
本文对青海地区1204例口腔颌面部肿瘤、囊肿、瘤样病变的病变部位、性质、年龄及性别进行分析。结果为良性肿瘤634例(52.66%),以血管瘤和涎腺混合瘤最多见。恶性肿瘤232例(1.27%),以鳞状细胞癌居第一位,平均患病年龄48岁,随年龄增长,逐年递增。囊肿306例(25.41%),多发生在去下腺。瘤样病变32例(2.66%),多为牙龈瘤。本组良性肿瘤女性高于男性,血管瘤居第一位。良恶性肿瘤之比为2.73∶1,与国内有关报道略有不同。  相似文献   
72.
Background: High concentrations of propidium iodide (PI), in combination with fluorescein isothiocyanate (FITC) and R-phycoerythrin (RPE) used for multiparameter DNA flow cytometry (FCM), cause spectral cross-talk into the green fluorescence channel (FL1). We have evaluated the use of post-acquisition software compensation (N-Color Compensation) in order to correct this spectral cross-talk caused by PI. Method: Cell mixtures were prepared consisting of keratin 8/18 FITC labeled, keratin 8/18 RPE labeled, and unlabeled MCF-7 breast carcinoma cells. DNA was stained with PI (100 μM). Post-acquisition software compensation was applied to correct the spectral cross-talk of PI fluorescence. Secondly, the distribution of the Ki-67 (FITC) protein during the cell cycle (PI) of SiHa cervical carcinoma cells (no software compensation) was compared to the Ki-67 expression pattern of SiHa cells, simultaneously stained for keratin 8 (RPE), after applying software compensation. Finally, software compensation was used to compare the relative levels of PCNA and p53 expression in two clinical ovarian cancer ascites specimens, stained for PCNA or p53 (FITC), keratin 8/18 (RPE), and DNA (PI), with a known p53 status (positive and negative, respectively). Results: The Ki-67 cell cycle-dependent pattern of a triply stained sample (Ki-67 (FITC), keratin 8 (RPE), and DNA (PI)) is restored after software compensation and the results are comparable to the Ki-67 distribution of a sample stained solely for Ki-67 and DNA. P53 expression could only be resolved after using software compensation in the p53 positive ovarian ascites (OA) sample. Conclusions: We conclude that software compensation is a robust and reliable post-acquisition method for the correction of RPE/PI spectral cross-talk, permitting better identification of weakly expressed proteins in heterogeneous clinical tumor samples stained for multiple cellular antigens and DNA using PI.  相似文献   
73.
目的 探讨脑囊虫病患者各期脑脊液中的一氧化氮 (NO)、肿瘤坏死因子α(TNF α)的变化规律及它们在脑囊虫病中的作用机制。方法 检测 4 9例明确诊断并依据MR分期 ,单发脑实质内囊虫的脑囊虫病患者和 2 0名对照者脑脊液中NO、TNF α水平。结果 NO在脑囊虫病的Ⅰ期显著降低而TNF α水平呈显著升高 ,NO、TNF α于Ⅱ期、Ⅲ期 (整个退变死亡期 )均表现为高水平 ,Ⅳ期恢复正常 ,NO和TNF α存在高度正相关关系。结论 在单发脑实质内囊虫病中NO、TNF α可能参与杀虫作用 ,其免疫调节与杀虫机制存在着动态平衡 ,参与感染控制  相似文献   
74.
胆囊结石及癌变过程中肿瘤坏死因子可溶性受体的变化   总被引:1,自引:1,他引:0  
目的 探讨可容性肿瘤坏死因子受体 (sTNFR)在胆囊结石及癌变过程中的变化。方法 用双抗体夹心酶联免疫法对 5 3例胆囊结石 ,9例胆囊癌及 11例正常对照者血清及胆法中的sTNFR水平进行检测。结果 血清及胆汁中sTNFR水平胆囊癌组为 (2 .63± 0 .5 6) μg/L、(10 .0 2± 3 .2 3 ) μg/L较胆石症组 (1.2 5± 0 .3 6) μg/L、(2 .81± 0 .93 ) μg/L及对照组 (0 .95± 0 .19)μg/L、(1.83± 0 .5 4) μg/L均显著升高 (P <0 .0 1)。胆囊黏膜从典型增生、非典型增生到胆囊癌的发展过程中sTNFR在血清 (1.11± 0 .2 8、1.5 3± 0 .3 2、2 .63± 0 .5 6)及胆汁中 (2 .5 0± 0 .81、3 .42±0 .87、10 .0 2± 3 .2 3 )逐级增高 (各组间P <0 .0 5 )。胆汁中sTNFR水平在胆囊癌Ⅰ~Ⅲ期 (8.3 6±2 .60 )与Ⅳ~Ⅴ期 (13 .3 3± 4.46)间差异有显著性 (P <0 .0 0 1) ,肿瘤直径≥ 2cm组 (12 .10± 2 .3 2 )与 <2cm组 (7.42± 2 .10 )间差异有显著性 (P <0 .0 5 )。胆汁中TNFR水平明显高于其对应的血清水平 ,两者之间呈正直线相关 (r =0 .875 ,P <0 .0 0 1)。胆囊癌术后血清sTNFR水平显著下降。结论 sTNFR参与胆囊结石致癌的过程 ,与胆囊癌的临床生物学特点密切相关。  相似文献   
75.
参附注射液对肠缺血-再灌注大鼠肿瘤坏死因子α的影响   总被引:5,自引:0,他引:5  
目的观察肿瘤坏死因子α(TNF-α)在大鼠肠缺血-再灌注损伤过程中的作用及参附注射液对TNF-α的影响,探讨参附注射液防治肠缺血-再灌注损伤机制。方法 SD大鼠随机分为肠缺血-再灌注组(IR组)、参附注射液预处理组(SF组)和假手术组(C组)。采用阻断肠系膜上动脉(SMA)的方法制造肠缺血-再灌注模型。分别测定各组动物血浆、肠组织TNF-α含量及血液动力学变化;光镜观察肠粘膜损伤情况。结果IR组再灌注后MAP下降,与C组和SF组比有显著性差异(P<0.01);SF组肠粘膜损伤程度减轻,与IR组比有显著性差异(P<0.01);SF组血浆及肠组织TNF-α水平降低,与IR组比有显著性差异(P<0.01)。结论参附注射液可明显防治大鼠肠缺血-再灌注导致的肠粘膜损伤,这种作用可能是通过抑制TNF-α的释放实现的。  相似文献   
76.
Our previous study demonstrated that pro-gastrin-releasing peptide(31–98), or ProGRP, is a specific tumor marker in patients with small cell lung carcinoma (SCLC). Using a newly developed, highly sensitive enzyme-linked immunosorbent assay (ELISA) for ProGRP, we analyzed 1,446 samples including those obtained from 478 lung cancer patients to evaluate the clinical usefulness of this ELISA. Several properties indicated that ProGRP is a useful tumor marker for SCLC. First, ProGRP was specifically elevated in SCLC patients. In non-SCLC patients and patients with non-tumorous lung diseases, its serum level was very rarely elevated. Secondly, ProGRP was a reliable marker, in terms of the marked elevation of serum ProGRP levels in SCLC patients. Thirdly, serum ProGRP levels were elevated in SCLC patients even at a relatively early stage of this disease. Fourthly, changes in the serum ProGRP level showed an excellent correlation with the therapeutic responses in SCLC patients. Neuron-specific enolase (NSE) is accepted as a tumor marker of SCLC patients. With the aim of comparing ProGRP and NSE as tumor markers for SCLC patients, we measured serum NSE levels in all samples collected in the present study. We found that ProGRP was superior to NSE in terms of sensitivity, specificity and reliability. Therefore, we consider that ProGRP can play a major role as a clinical tumor marker for SCLC patients.  相似文献   
77.
本文采用S-100蛋白为免疫学标记,对34例恶性肿瘤局部淋巴结内树突状细胞进行免疫组化定量研究。结果按S-100蛋白阳性细胞数目多少分为增多(7例)、减少(20例)及正常(7例)3组,统计学分析增多组均值(164.4个/mm^2)明显高于对照组(58.3个/mm^2);减少组均值(16.5个/mm^2)组显低于对照组;而正常组均值(69.8个/mm^2)与对照组无显著差异。  相似文献   
78.
Anti-tumor necrosis factor (TNF) antibodies inhibit passively transferred experimental allergic encephalomyelitis (EAE) in SJL mice. The possibility that this occurs through interference in TNF's upregulation of endothelial cell adhesion molecules was investigated. Expression of both vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) on spinal cord vessels increased during EAE. The upregulation of VCAM-1 was markedly reduced or prevented by anti-TNF treatment. Leukocytic infiltration was 15-fold lower in anti-TNF-treated than diseased animals. Spinal cord endothelial expression of VCAM-1, though not ICAM-1 or fibronectin, positively correlated with the extent of T cell, B cell or monocyte infiltration in each animal.  相似文献   
79.
本文应用L929细胞杀伤法,对注射旋毛虫肌肉期幼虫分泌物(L1ES)的小鼠血清进行了检测,发现L1ES对已注射卡介苗(BCG)或感染旋毛虫的小鼠,均能诱生肿瘤细胞毒因子(TCF),而正常对照鼠则不能发生,表明L1ES诱生TCF需要首先激活巨噬细胞(Mφ)这一基本条件。将L1ES置37℃、1h,56℃、30min或100℃、2min处理后,其诱生TCF的能力均明显高于对照组(P<0.05)。L1ES  相似文献   
80.
The properties of [3H]dihydropyridine (DHP), nitrendipine and (+)-PN 200-110, binding to rat cerebral membranes were investigated. In normotensive Wistar-Kyoto (WKY) adult rats, the highest densities of [3H]DHP binding sites were found in the hippocampus. Frontal cerebral cortex and hypothalamus had intermediate levels and no specific binding of [3H]DHP and [125I]iodipine could be detected in the brainstem membranes and more precisely in the nucleus tractus solitarius and in the locus coeruleus. Changes in the maximal number of DHP binding sites (Bmax) were observed in spontaneously hypertensive rats (SHR) and in old Sprague-Dawley rats. In adult SHR, there was a significant increase in theBmax values of [3H](+)-PN 200-110 binding in the hippocampus when compared to the values obtained in WKY. There was no difference in theBmax values between young (3 weeks) prehypertensive SHR and age-matched WKY. In senescent (26 months) Sprague-Dawley rats, theBmax values of [3H](+)-PN 200-110 binding were significantly reduced (30%) in the frontal cerebral cortex and the hippocampus, as compared with the number of DHP binding sites found in mature Sprague-Dawley rats (15 weeks).  相似文献   
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