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61.
Cells of the human tumor cell line RMG-1, derived from a clear-cell adenocarcinoma of the ovary, were injected intraperitoneally into nude mice, and the cells obtained from the tumor nodules in the mesenterium were found to form a larger number of, and larger-sized, tumor nodules than the original RMG-1 cells. The RMG-1-h cells, transferred into culture from the tumor nodules after a 4th in vivo passage, showed a dissemination potential as high as that of cells disseminating directly from the tissues, and exceedingly higher than that of RMG-1 cells. To assess the molecular bases of the different biological properties of RMG-1 and RMG-1-h cells, we compared the content and expression of various carbohydrate antigens in both cells. The chromosomal profile of RMG-1-h cells revealed their human origin and was identical to that of the original RMG-1 cells. In contrast to the broad histogram for the Lex-bearing cells among RMG-1 cells in flow cytometry, the weakly and moderately positive cells toward anti-Lex antibody were found to be eliminated from the histogram for the RMG-1-h cells, resulting in the enrichment of cells strongly expressing Lex, which may account for the high dissemination potential. In addition, the adhesion of RMG-1 cells to mesothelial cells was found to be significantly inhibited by pretreatment of the cells with anti-Lex antibody, indicating Lex-mediated cell-to-cell interaction between ovarian cancer cells and mesothelial cells. By TLC-immunostaining, two Lex-glycolipids, III3Fucα-nLc4Cer and V3Fucα-nLc6Cer were detected in both RMG-1 and RMG-1-h cells, and their total concentrations were not significantly different from each other. However, the hydrophobic moieties of Lex-glycolipids in RMG-1-h cells were different from those in RMG-1 cells, suggesting that a difference in the structure of the hydrophobic moieties of Lex is partly involved in the enhanced reactivity of RMG-1-h cells toward anti-Lex antibody. Thus, the high dissemination potential of ovarian cancer cells was shown to be mediated by the Lex-determinant and the Lex-bearing cells are enriched by repeated in vivo passage of the cells into nude mice.  相似文献   
62.
In the present study, we found that inostamycin increased the ability of paclitaxel to induce apoptosis in Ms-1 cells. A considerably higher concentration of paclitaxel was required for the induction of apoptosis in Ms-1 cells than in other cell lines tested. Treatment of Ms-1 cells with inostamycin, an inhibitor of phosphatidylinositol (PI) synthesis, reduced the dosage of paclitaxel required to induce cell death by apoptosis. This effect of inostamycin is specific to Ms-1 cells, and inostamycin did not increase the cytotoxicity of other antitumor drugs such as adriamycin, vinblastine, methotrexate, cisplatin, etoposide, or camptothecin in Ms-1 cells. Addition of inostamycin to paclitaxel-treated cells caused a significant increase in the sub G1 peak, representing apoptosis, which was accompanied by a decrease in the G2/M peak seen in paclitaxel-treated Ms-1 cells, without affecting paclitaxel-inhibited tubulin depolymerization. Moreover, paclitaxel did not enhance inostamycin-inhibited PI synthesis. The expression levels of Bcl-2, Bax, and Bcl-XL were not changed following the co-treatment with inostamycin plus paclitaxel, whereas the activated form of caspase-3 was markedly increased. Thus, inostamycin is a chemosensitizer of paclitaxel in small cell lung carcinoma Ms-1 cells.  相似文献   
63.
尖吻蝮蛇毒中一种新类凝血酶的分离纯化   总被引:6,自引:1,他引:6  
用阴离子交换色谱和凝胶过滤色谱技术,从尖吻蝮蛇毒中纯化得到一个具有凝血活性的组分.经Superdex 75 HR10/30预装柱检测,纯度达99.91%.SDS-PAGE显示为单一条带,还原、非还原条件下分子量分别为59.25k、52.58k.该组分的凝血酶比活为41.5u/mg,精氨酸酯酶比活为14.29u/mg,但不激活血浆凝血因子ⅩⅢ.EDTA不能抑制其凝血活性,而苯甲磺酰氟则产生不可逆抑制作用.结果表明该酶是一种新尖吻蝮蛇毒类凝血酶.  相似文献   
64.
广州地区2001年~2003年抗高血压药物利用调查分析   总被引:2,自引:0,他引:2  
目的:了解广州地区抗高血压药物的应用情况.方法:采用DDD分析法和金额排序法,对广州地区医院2001年~2003年间抗高血压药购入数据进行综合统计分析.结果:3年来,钙通道阻滞剂所占比例最大,平均为38.98%.其次是血管紧张素转换酶抑制剂(ACEI),平均为31.6%.合资药氨氯地平在DDDs排序及金额排序中均居首位.结论:钙通道阻滞剂、ACEI类药物为抗高血压的主流药,氨氯地平占有重要的临床地位.  相似文献   
65.
目的:分析与总结苏州大学附属儿童医院临床试验机构质控中发现的问题。 方法:按照国家药品监督管理局食品药品 审核查验中心最新发布的核查要点对 2021 年 1 月-2023 年 6 月机构质控报告中的问题进行整理与归类。 结果:本机构临床试 验项目质控中发现的问题主要集中在研究人员资质文件收集、知情同意书签署、异常值评判、试验数据记录等方面。 结论:临床 试验机构、伦理委员会、研究者和申办方均应履行各自职责,对试验质量全程把关,保障受试者的权益与安全、保证临床试验数 据的真实性。  相似文献   
66.
PurposeCurrent clinical guidelines are unclear regarding the association of cardiovascular medication with the risk of acute exacerbation (AE) in patients with asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO).MethodsWe conducted a retrospective cohort study by interrogating the claims database of Taipei Veterans General Hospital. Patients with coexistent fixed airflow limitation and asthma were enrolled as an ACO cohort between 2009 and 2017. Exposure to cardiovascular medications, including angiotensin converting enzyme inhibitors (ACEIs), angiotensin II receptor blockers (ARBs), non-selective beta-blockers, cardioselective beta-blockers, dihydropyridine (DHP) calcium channel blockers (CCBs), and non-DHP CCBs, in 3-month period each served as time-dependent covariates. Patients receiving a cardiovascular medication ≥ 28 cumulative daily doses were defined as respective cardiovascular medication users. Patients were followed up until December 31, 2018. The primary endpoint was severe AE, defined as hospitalization or emergency department visit for either asthma, COPD, or respiratory failure. The secondary outcome was moderate AE.ResultsThe final study cohort consisted of 582 ACO subjects, with a mean follow-up period of 2.98 years. After adjustment, ARB (hazard ratio [HR], 0.64, 95% confidence interval [CI], 0.44–0.93, P = 0.019), cardioselective beta-blocker (HR, 0.29, 95% CI, 0.11–0.72, P = 0.008) and DHP CCB (HR, 0.66, 95% CI, 0.45–0.97, P = 0.035) therapies were associated with lower risks of severe AE. ARB (HR, 0.42, 95% CI, 0.30–0.62, P < 0.001) and DHP CCB (HR, 0.55, 95% CI, 0.38–0.80, P = 0.002) therapies were associated with lower risks of moderate AE. Cardioselective beta-blockers, ARBs, and DHP CCBs were associated with lower risks of severe AE in frequent exacerbators. ACEI, non-selective beta-blocker, or non-DHP CCB use did not change the risk of severe AE.ConclusionsARB, cardioselective beta-blocker, and DHP CCB therapies may lower the risk of AE in patients with ACO.  相似文献   
67.
ACE2基因多态性与原发性高血压的关系   总被引:2,自引:1,他引:1  
目的 研究血管紧张素转化酶2(angiotensin converting enzyme 2,ACE2)基因多态性与广东地区原发性高血压的相关性.方法 高血压组选择门诊与住院的汉族无血缘关系的原发性高血压369例,男194例,女175例;对照组为同期体检的广东地区健康汉族居民199例,男101例,女98例.排除冠心病、高血压、糖尿病、脑血管病及肝功能不良、肾功能不良.按照性别分为两组,采用病例对照的原则,应用聚合酶链反应和限制性内切酶片段长度多态性(polymerase chain reaction and restriction fragment length polymorphism,PCR-RFLP)的方法检测ACE2基因G9570A多态性,并随机抽取20份标本进行基因测序以核实基因分型.在分析各亚组的年龄、体重指数、血压及生化指标的基础上综合分析ACE2基因多态性与原发性高血压的关系.结果 高血压组G等位基因频率:男75.3%,对照组男60.4%,差异有统计学意义(χ2=7.0086,P=0.0081),高血压组,女57.4%,对照组45.4%,差异有统计学意义(χ2=6.9443,P=0.0084);女高血压组GG基因型的频率明显高于对照组(χ2=12.9499,P=0.0015);G等位基因人群发生高血压的风险高于A等位基因人群,男OR:1.9945,95% CI:1.1916~3.3385,P=0.0082;女OR:1.603,95% CI:1.1274~2.2792,P=0.0085.结论 ACE2-G9570A多态性与原发性高血压相关;携带G等位基因的男性和仅仅携带G基因的女性人群发生高血压的危险性相对较大,提示ACE2基因可作为原发性高血压的候选易感基因.  相似文献   
68.
中药黄曲霉毒素B1的含量考察   总被引:6,自引:0,他引:6  
匡佩琳 《中成药》2000,22(7):478-479
为制定中药AF-B1含量限度提供依据。方法:间接竞酶联免疫吸附法。结果:样品AF-B1含量在1.14-3.72μg/kg之间。结论:制定中药AF-B1含量限度是必要的。  相似文献   
69.
围绕慢性乙肝这一严重影响人类公共卫生的重大社会问题,开展中医药治疗的研究与探索,首先应肯定中医药治疗CHB具有临床疗效及优势,使其成为治疗CHB的主要方法;继而采用健康教育与药物治疗相结合,运用正确的中医认识和思维方法,结合生物医学的最新研究进展,根据病证结合的方法进行分阶段治疗;并选择宏观症状的改善和微观检查指标的应答及生存质量的提高为观察指标,合理而有效的评价其临床疗效。  相似文献   
70.
中药饮片质量标准是中药炮制研究的重要内容,也是整个中药标准化体系的关键环节。尽管中药饮片有了国家标准,但是中药饮片标准化水平仍然处于较低水平。在中药饮片质量标准研究中,还存在一些实际问题需要我们加以重视和思考。本文结合作者长期的研究和生产实践,提出在中药饮片质量标准研究中要更加注重和传统炮制理论、炮制机理研究与药效物质研究的结合,努力构建更加全面、科学、合理的中药饮片质量标准。  相似文献   
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