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1.
Dipeptidyl peptidase IV (DPP-IV) is a cell surface ectopeptidase that has been implicated in cell-extracellular matrix interactions, lymphocyte growth and the regulation of biological peptides. Previous studies have shown that immunostaining for DPP-IV and DPP-IV enzyme levels is decreased in hepatoma cells and levels have been correlated with the ability of such cells to adhere in vitro. The aim of this paper was to measure DPP-IV enzyme levels in rat hepatoma cells and to examine whether changes were associated with alterations at the mRNA level. The results indicate a greater than 90% reduction in DPP-IV enzyme levels in two rat hepatoma cell lines, HTC and H35, compared with rat hepatocytes. Enzyme levels of the control enzyme leucine aminopeptidase (LAP) were not decreased. mRNA studies indicated that these changes were associated with similar reductions in rat DPP-IV mRNA. It is concluded that DPP-IV is markedly reduced at the protein, enzyme and mRNA levels in rat hepatoma cells. The significance of these changes is unclear but may lead to decreased extracellular matrix interactions by such cells.  相似文献   
2.
本文研究指出,Line10肝癌腹水上清具有一定的免疫抑制作用,可致巨噬细胞形态改变并降低其吞噬功能,还可使BALB/c小鼠的白细胞数量下降。应用Ouchterlony法证明Line10肝癌腹水上清中存在line10肝癌细胞的抗原成分。  相似文献   
3.
目的 探讨全身热疗法(whole body hyperthermia,WBH)治疗肝脏恶性肿瘤的疗效及其对肝功能的影响。方法 采用WBH治疗肝脏恶性肿瘤患者39例,并对治疗前、后患者肝功能指标进行动态观察,分析该疗法对肝脏功能的影响,并通过分析治疗效果,初步评估该疗法的疗效。结果 ①WBH治疗不能手术切除的晚期肝脏恶性肿瘤患者的有效率为61.5%(24/39),60.0%(9/15)的患者AFP有不同程度下降,肿瘤疼痛缓解率达100%;存活期〉2年者占12.8%(5/39),〉1年者占59.0%(23/39),〉6个月者占76.9%(30/39)。②谷丙转氨酶于治疗后1~3d出现明显升高(P〈0.05),7d后下降并接近治疗前水平;谷草转氨酶于治疗后1d明显升高(P〈0.05),3~7d则下降并接近治疗前水平;白蛋白于治疗后1d出现下降(P〈0.05),但3d即已恢复;肝功能正常组总胆红素于治疗后第1~3d出现升高(P〈0.05),而肝功能异常组未观察到同样变化;转肽酶则无明显变化。结论 WBH能改善晚期肝脏恶性肿瘤患者的预后,提高生存质量,延长生存时间,但同时可造成患者肝功能一定程度的可逆性损害。  相似文献   
4.
报告16例大肝癌手术切除治疗效果,癌块直径>7cm。其中巨块型12例,癌块>10cm9例;癌块>14cm3例,均经病理证实。Ⅱ期切除3例,均经肝固有动脉结扎加插管注药化疗,肿块缩小后再手术,术后生存1年4例,2年3例,3年4例,4年1例,全组中位生存期24.1个月,并对大肝癌的手术适应证及术式选择等进行了探讨。  相似文献   
5.
影响原发性肝癌介入治疗生存因素的Cox模型分析   总被引:2,自引:0,他引:2  
目的:了解三种介入治疗方法对原发肝癌生存因素的影响。方法:应用Cox回归模型对298例不能切除的原发性肝癌介入治疗后的预后进行多因素分析。结果:23项指标中筛选出对生存影响显著的6项因素。按其对生存影响的大小排列分别为:肿瘤大小、二步切除、肿瘤数目、动静脉瘘、门脉癌栓和介入次数。结论:二步切除和介入次数为保护因子,能延长生存期。其余4项为危险因子,可缩短生存期。  相似文献   
6.
应用HAg 18-1 ELIsA诊断药盒,对原发性肝癌(PHc)、肝炎及肝炎伴有肝硬化、其他癌(肺癌、胃癌、结肠癌)以及正常人,共400例,进行了血清学的检测。结果显示:HAg 18-1 ELISA阳性检测率,PHC为81%,肝炎及伴有肝硬化为30%,肺癌为36%,胃癌为28%,结肠癌为12%,正常人为0。PHC组HAg 18-1 ELISA检测阳性率显著高于其他各组(P<0.05)。此外PHC 80例中有56例同时伴有AFP的检测,其中AFP 17/56阴性,17例阴性中HAg 18-1 ELISA检测阳性10例(59%),故对AFP检测PHC具有明显协同和补充诊断价值。此药盒操作简便,易于推扩,对PHC的临床诊断和普查提供了新方法。  相似文献   
7.
本文应用抗癌基因ras表达产物P21ras蛋白的大鼠单克隆抗体建立的双抗体夹心ELISA法,检测了肝癌及癌病变前病人血清中p21ras蛋白的浓度。所获阳性检出率分别为:慢性乙型肝炎为13.0%(12/92),肝硬化为27.8%(10/36)和肝癌为50.0%(8/16)。另外,对试验方法的敏感性、特异性及稳定性,以及检测P21ras蛋白与AFP的关系进行了评价。结果表明,P21ras蛋白的过高表达发生在肝细胞癌变之前。提示在慢性乙型肝炎及肝硬化病人血清中检出P21ras蛋白,是预测肝细胞癌变的危险信号。  相似文献   
8.
Rat ascites hepatoma AH7974 cells strongly expressed antilaminin antibody-reactive substances (laminin-like substances) andGriffonia simplicifolia isolectin B4 (GS)-reactive carbohydrate (alpha)-d-galactose; alpha-Gal) on their cell surface. The alpha-Gal expression was not apparently influenced by the pretreatment of cells with methanol. The cell membrane laminin-like substances had approximate molecular weights of 150, 62 and 56 kDa in denaturating reducing conditions, of which the 62 and 56 kDa bands were stained with GS. The cell membrane molecules bearing alpha-Gal were 62 and 56 kDa and were stained with antilaminin antibody. Therefore, the major molecules bearing alpha-Gal residues of AH7974 cell membrane are considered to be laminin-like substances. To determine the role of the substances in metastasis, we selected four cell lines (74AD, 74AD-f, 74FL, 74FL-a) from AH7974 in culture. 74AD and 74FL-a are adherent lines and 74AD-f and 74FL are floating lines. All of these cell lines strongly expressed laminin-like substances, but a marked difference was found in expression of alpha-Gal, which was most strongly expressed by 74FL, followed by 74AD, and rarely by 74AD-f and 74FL-a; the staining intensity was positively correlated with their experimental lung-colonizing potential. Cell membrane laminin-like substances were 200, 97, 62, 56 and 46 kDa and among them 62 and 56 kDa molecules were glycosylated with alpha-Gal. The pretreatment of 74FL cells with antilaminin antibody or with human type A serum (containing natural antibody to alpha-Gal epitope) depressed remarkably the lung-colonizing potential of the cells. These results suggest that the expression of 62 and 56 kDa laminin-like substances with alpha-Gal residues on tumor cell surfaces is one of the determinants associated with lung-colonizing potential of these cells.  相似文献   
9.
A simple technique for controlling cell adhesion on glass substrates by surface modification using a commercially available poly(ethylene glycol) (PEG) disilane, which can bind directly to glass in a single step, in combination with photolithographic micropatterning, was developed, characterized, and evaluated for patterning of HepG2 hepatoma cells and 3T3 fibroblasts. The optimal concentration of PEG-disilane for surface modification was 5 mM, and patterning of strongly adherent cells such as HepG2 required the chelation of divalent metal cations in order to inhibit nonspecific binding and cell aggregation. Whereas the average thickness of the PEG-disilane layer was 18±3.5 nm, the perimeters of patterned areas of exposed glass exhibited ridges of average height 857±50 nm, which may have aided in constraining cell spreading and migration. Although unpatterned PEG-treated substrates were hydrophilic (contact angle 46±1°), micropatterned surfaces behaved as if they were somewhat hydrophobic (contact angle 90°), necessitating special protocols for preventing deleterious dewetting of cells. For optimized protocols, the probability of adhesion of HepG2 cells to a patterned area of exposed glass was almost 15 times higher than the probability of adhesion to a PEG-treated background region of equal area. Our technique is useful for short- to intermediate-term patterning of cell or tissue morphology, e.g., for investigation of the effects of cell–cell interactions or cell geometry.  相似文献   
10.
In the cirrhotic and precirrhotic liver, there may be small foci with increased cellularity and amphophilic cytoplasm. These are microscopic lesions that do not form macroscopically detectable nodules, which differ from the macroscopically apparent nodules of dysplastic nodules. In the present study, we assessed the proliferating activity of 12 hyperplastic foci in 11 patients with cirrhosis or chronic hepatitis, by staining for agyrophilic nucleolar organizing regions (AgNOR). The mean AgNOR count per nucleus in the hyperplastic foci ranged from 0.96 to 1.36 (mean, 1.13; SD 0.12), and from 0.81 to 1.06 (mean, 0.94; SD 0.08) in the controls. The AgNOR count In the hyperplastic foci was significantly higher than that In the controls (P> 30.01). Small hyperplastic foci show Increased proliferative activity. Further study on these foci is required to clarify their relation to hepatocarcinogenesis.  相似文献   
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