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991.
冯凤芝  向阳  张卫光  崔竹梅  张颖  杨秀玉 《肿瘤》2003,23(4):283-286
目的 将人肿瘤坏死因子-alpha(hTNF-α)基因导入已建立的绒癌耐药细胞系,观察hTNF-α基因转导后对绒癌细胞耐药性逆转的体外作用。方法 通过阳离子脂质体将hTNF-α基因转导绒癌耐药细胞系,用新霉素筛选含hTNF-α片段的单细胞克隆,用RT-PCR方法和细胞免疫组织化学方法,检测转导hTNF-α基因的耐药细胞中MDRl mRNA和MDRl蛋白(P-gp)表,达水平的改变。采用四甲基偶氮唑蓝比色法,检测转导hTNF-α基因的耐药细胞对足叶乙甙(VP-16)的耐药指数。结果 转导hTNF-α基因后,绒癌耐药细胞中检测出hTNF-α mRNA表达,转导hTNF-α基因在mRNA水平能一定程度的逆转绒癌耐药细胞的MDRl,而在P-gp蛋白水平几乎能完全逆转绒癌耐药细胞的MDRl。转导hTNF-α基因的细胞的耐药指数明显降低。结论 hTNF-α基因转导后,可通过调节MDRl的表达,来逆转绒癌耐药细胞系的耐药性。  相似文献   
992.
[目的]探讨胃黏膜良恶性病变幽门螺杆菌(Hp)感染与突变型p53、bcl-2、增殖细胞核抗原(PCNA)表达之间的关系。[方法]用免疫组织化学SP法对115例胃黏膜良、恶性病变[慢性浅表性胃炎(CSG)25例,慢性萎缩性胃炎(CAG)25例,异型增生(GED)25例,胃癌(GCA)40例]的胃镜活检标本进行幽门螺杆菌感染的检测和突变型p53、bcl-2、PCNA表达的研究。[结果]在CSG、CAG、GED、GCA的各病变中幽门螺杆菌感染检出率分别为36%(9/25)、48%(12/25)、72%(18/25)、58%(23/40);与20例正常胃黏膜Hp检测阳性率(20%)作比较,除了CSG无统计学意义外,其余几组均有显著性差异(P<0.05);突变型p53检出率分别为0、0、24%(6/25)、55%(22/40);胃炎、异型增生、胃癌三者之比有显著性差异(P<0.05);bcl-2检出率44%(11/25)、52%(13/25)、76%(19/25)、57.5%(23/40);PCNA在CSG、CAG、GED、GCA中的表达呈现递增性,经Ridit检验P<0.05;Hp感染与PCNA表达强级(阳性细胞>50%)、p53阳性病例均有显著相关性(P<0.01)。[结论]Hp的感染与突变型p53、bcl-2、PCNA在胃黏膜异型增生,胃  相似文献   
993.
PURPOSE: Evaluate p7 expression in human breast cancer and determine whether chemotherapy and radiation therapy effect a change in p7 expression. EXPERIMENTAL DESIGN: Using a p7-specific monoclonal antibody with immunohistochemistry and Western immunoblot analyses to assess p7 expression in archival, frozen breast cancer specimens both before and after therapy. RESULTS: A novel 7 kDa protein (p7), originally identified in multidrug-resistant ovarian and breast cancer cell lines, was found to be expressed in 21 of 64 (32%) primary, unselected human breast cancer specimens by immunohistochemistry with the use of a p7-specific monoclonal antibody, 1D7. P7 was observed in malignant cells but not in other types of cells in the breast tissue. Western blot analysis confirmed the 7 kDa polypeptide in p7-positive breast carcinomas identified by immunohistochemistry. P7 expression was significantly associated with breast cancers having distant metastasis and/or local recurrence (P = 0.027, Fisher's exact test). In addition, p7 expression was significantly increased in post-treatment breast cancer biopsy specimens compared with pretreatment breast cancer biopsy specimens in patients with locally advanced breast cancer after 5-fluorouracil chemotherapy and radiation therapy [2 of 15 (13%) pretreatment breast cancers compared with 8 of 15 (53%) post-treatment breast cancers; P = 0.016, McNemar's test]. CONCLUSIONS: These findings demonstrate that expression of p7 is associated with malignant tumor cells in primary breast cancers, especially those showing recurrent or metastatic disease. Its specific association with the malignant phenotype suggests it may have potential for novel target-based therapies. The markedly increased expression in patients with locally advanced disease after neoadjuvant therapy suggests a role for p7 in treatment outcome.  相似文献   
994.
995.
PURPOSE: C-Jun NH(2)-terminal kinase (JNK) has been implicated in numerous functions including stress responses, apoptosis,and transformation. The role in transformation is based largely on studies of isolated cell types with little indication of whether JNK plays a general role in a specific human tumor type or whether this occurs in vivo. EXPERIMENTAL DESIGN: We examined 9 human prostate carcinoma cell lines in vitro and a representative line in vivo. RESULTS: For all of the cell lines proliferation is highly correlated with serum-supported JNK activity (r(Pearson) = 0.91; P = 0.004), whereas no relationship was observed for 10 human breast cancer cell lines (r(Pearson) = -0.32). Treatment with characterized antisense oligonucleotides complementary to sequences common to either the JNK1 or JNK2 family of isoforms showed that, whereas antisense JNK1 inhibited growth by a maximum of 57%, antisense JNK2 inhibited proliferation up to 80%. Sense and scrambled control oligonucleotides had little effect (average 3.7 +/- 1.5%). Moreover, systemic treatment of mice bearing established xenografts of PC3 prostate carcinoma cells with antisense JNK1 and JNK2 led to inhibition tumor growth by 57% (P < 0.002) and 80% (P < 0.001), respectively. The difference is significant (P < 0.012). Combined antisense treatment led to a significant increase in frequency of tumor regression (P = 0.022). CONCLUSION: These results indicate that JNK is required for growth of prostate carcinoma cells in vitro and in vivo, and additionally indicate that JNK2 plays a dominant role. The JNK pathway is a novel target in the treatment of prostate carcinoma.  相似文献   
996.
PURPOSE: We conducted this study because the duration of excess lung cancer risk among former smokers has been inconsistently reported, doubt has been raised regarding the population impact of smoking cessation, and differential risk reduction by histologic cell type after smoking cessation needs to be confirmed. METHODS: The Iowa Women's Health Study is a prospective cohort study of 41,836 Iowa women aged 55 to 69 years. In 1986, mailed questionnaires were used to collect detailed smoking history. Age-adjusted lung cancer incidence through 1999 was analyzed according to years of smoking abstinence. Relative risks were estimated using Cox regression analysis. RESULTS: There were 37,078 women in the analytic cohort. Compared with the never smokers, former smokers had an elevated lung cancer risk (relative risk, 6.6; 95% confidence interval, 5.0 to 8.7) up to 30 years after smoking cessation for all former smokers. However, a beneficial effect of smoking cessation was observed among recent and distant former smokers. The risk of adenocarcinoma remained elevated up to 30 years for both former heavier and former lighter smokers. CONCLUSION: The risk for lung cancer is increased for both current and former smokers compared with never smokers and declines for former smokers with increasing duration of abstinence. The decline in excess lung cancer risk among former smokers is prolonged compared with other studies, especially for adenocarcinoma and for heavy smokers, suggesting that more emphasis should be placed on smoking prevention and lung cancer chemoprevention.  相似文献   
997.
PURPOSE: This study was conducted to determine whether relatives of gastric cancer patients (GCF) showed greater gastric cycloxygenase-2 (COX-2) expression or a greater incidence of precancerous lesions after Helicobacter pylori infection and whether H. pylori eradication could reduce COX-2 expression. EXPERIMENTAL DESIGN: Three hundred subjects were enrolled in this study: half were relatives of 50 H. pylori-infected gastric cancer patients, and half were relatives of 50 H. pylori-infected duodenal ulcer (DU) patients (controls). Each relative underwent endoscopy to detect H. pylori infection and related gastric histology. One hundred and twenty GCFs were found to have H. pylori infection. After H. pylori eradication, 90 of the 120 GCFs were followed up with annual endoscopy examinations over the next 2 years. Gastric COX-2 intensity in all of the specimens collected from these patients was immunochemically stained and graded from 0 to 4. RESULTS: H. pylori infection, gastric atrophy, and intestinal metaplasia (IM) were more prevalent in GCFs than in relatives of H. pylori-infected patients with DUs (P < 0.05). H. pylori-infected GCFs also showed a greater COX-2 intensity than H. pylori-infected relatives of patients with DUs (89.1% versus 62.7%, P < 0.001; relative risk: 4.9; 95% confidence interval: approximately 2.34-10.29). Among the H. pylori-infected GCFs, COX-2 intensity correlated with atrophy and IM (P < 0.001). After H. pylori eradication, gastric COX-2 expression disappeared only in those relatives without IM (P < 0.001). CONCLUSIONS: GCFs are more likely to show greater gastric COX-2 expression and a higher incidence of precancerous lesions after H. pylori infection than the relatives of H. pylori-infected patients with only DUs. H. pylori eradication can reverse gastric COX-2 expression in patients without IM but not in patients with IM.  相似文献   
998.
目的 建立加替沙星制剂中加替沙星的含量及其有关物质测定的 RP- HPL C法。方法 采用Shimpack VP- ODS柱 (15 0 mm× 4 .6 mm,5 μm) ,流动相为 1%三乙胺 (磷酸调节 p H至 4 .5 ) -乙腈 (82∶ 18,体积比 ) ,检测波长 32 5 nm。结果 加替沙星在 2 .32~ 4 6 .4 8μg/ ml浓度范围内线性关系良好 ,日内及日间 RSD分别为 1.1%和 1.7%。平均回收率为 99.9% ,RSD为 0 .6 5 %。最低检测限为 0 .2 μg/ ml。结论 该方法简单 ,灵敏度高 ,结果准确 ,可用于加替沙星制剂的含量测定及有关物质检查。  相似文献   
999.
目的: 探讨一氧化氮合酶(nitric oxide synthase, NOS)抑制剂在实验性骨关节炎(osteoarthritis, OA)关节滑液中对前列腺素E2(prostaglandin E2, PGE2)的调节作用,为研制针对NO治疗OA的药物提供理论依据. 方法: 采用兔右后腿膝关节伸直位石膏管固定建立实验性OA模型,同时建立对照组,分别给予NOS抑制剂L-硝基精氨酸甲酯(L-NAME)或环氧化酶-2(COX-2)抑制剂塞来昔布, 检测各实验组关节滑液中的NO水平与PGE2的含量. 结果: L-NAME 石膏固定组的NO水平和PGE2浓度, 明显比单纯石膏固定组低,两者的差异有显著的统计意义(P<0.01),而塞来昔布 石膏固定组的NO水平,与单纯石膏固定组NO水平比较,两者的差异没有显著的统计学意义(P>0.05).结论: 实验性OA关节滑液中, NOS抑制剂L-NAME不仅能有效降低OA关节滑液中NO的水平,同时下调PGE2的浓度,而COX-2抑制剂对NO的水平无明显影响.  相似文献   
1000.
Jaffray C  Yang J  Carter G  Mendez C  Norman J 《Surgery》2000,128(2):225-231
BACKGROUND: Select pancreatic enzymes, primarily elastase, precipitate pulmonary injury similar to pancreatitis-associated adult respiratory distress syndrome and stimulate leukocyte cytokine production in vitro via nuclear factor kappa B (NF-kappaB) activation. This study explores the effect of systemic pancreatic enzymes on pulmonary NF-kappaB and inhibitory kappa B (IkappaB) proteins and their role in enzyme-induced pulmonary injury. METHODS: Mice received pancreatic elastase, amylase, lipase, or trypsin intraperitoneally. Bronchoalveolar lavage IkappaBalpha/IkappaBbeta proteins were measured by immunoblot. Pulmonary NF-kappaB activation, tumor necrosis factor (TNF) gene expression, and neutrophil infiltration (myeloperoxidase) were determined and myeloperoxidase experiments repeated in p55 TNF receptor-deficient (TNF KO) animals. Additional animals received pyrrolidine dithiocarbamate (PDTC), an inhibitor of NF-kappaB activation, and TNF protein and pulmonary microvascular permeability were measured after elastase administration. RESULTS: Pancreatic elastase induced pulmonary IkappaBalpha/IkappaBbeta degradation (30 minutes), NF-kappaB activation (60 minutes), and TNF gene expression (60 minutes) with subsequent neutrophilic inflammation (4 hours) and microvascular leakage (24 hours), whereas amylase, lipase, and trypsin did not. Furthermore, lung injury was markedly reduced in TNF KO animals and PDTC significantly attenuated TNF production and pulmonary microvascular leakage. CONCLUSIONS: Pancreatic elastase induces cytokine-mediated lung injury and this pathway involves the NF-kappaB second messenger system, further supporting elastase as a factor linking pancreatic inflammation to systemic illness during severe acute pancreatitis.  相似文献   
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