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991.
笔者2001年3月~2004年12月,用中医按摩手法,在辨证论治的基础上治疗泄泻105例,疗效满意,现报告如下。  相似文献   
992.
Molecular and traditional epidemiology studies have indicated a possible relationship between in utero environmental exposures and increased risk for childhood cancers, especially acute leukemias. Chromosomal aberrations have been associated with environmental exposures and cancer risk in adults. In order to more clearly define the association between prenatal exposures to carcinogenic polycyclic aromatic hydrocarbons (PAH) and chromosomal aberrations, chromosomal aberration frequencies were measured in a subset of 60 newborns from the Columbia Center for Children's Environmental Health (CCCEH) Prospective Cohort Study. The subset was composed of African American and Dominican, nonsmoking mother-newborn pairs residing in low-income neighborhoods of New York City, who were exposed to varying levels of airborne PAHs. Prenatal exposure was assessed by questionnaire, personal air monitoring during the third trimester, and PAH-DNA adducts in umbilical cord blood. Chromosomal aberrations were measured in cord blood lymphocytes by fluorescence in situ hybridization. PAH-DNA adducts were not associated with chromosomal aberrations. However, airborne PAHs were significantly associated with stable aberration frequencies in cord blood (P < 0.01). Moreover, stable aberration frequencies were significantly higher among African American newborns compared with Dominican, despite no significant differences in PAH exposure. These results show for the first time an association between prenatal exposure to airborne carcinogenic PAHs and chromosomal aberrations in cord blood, suggesting that such prenatal exposures have the potential to cause cytogenetic damage that has been related to increased cancer risk in other populations. If confirmed, this finding may open new avenues for prevention.  相似文献   
993.
PURPOSE AND EXPERIMENTAL DESIGN: The etiologic association and prognostic significance of mismatch repair gene/protein alterations have never been examined in nonsmoking lung cancer. Therefore, we investigated protein expression and promoter hypermethylation of hMLH1 and hMSH2 genes in the tumor specimens from 105 nonsmoking female non-small cell lung cancer (NSCLC) patients. Immunohistochemistry and restriction enzyme-based multiplex PCR were used to examine the protein expression and promoter hypermethylation, respectively. The occurrence of gene/protein alteration for each gene was compared with the patients' clinicopathologic variables as well as the overall survival and cancer-specific survival rates. RESULTS: Protein expression alteration and promoter hypermethylation were observed in 66% to 67% and 30% to 34% of tumor specimens for hMLH1 and hMSH2 genes, respectively. Loss of hMLH1 and hMSH2 protein expression was significantly associated with their promoter hypermethylation (P < 0.0001 and P = 0.049). The overall survival and cancer-specific survival rates were significantly lower in patients with promoter hypermethylation of hMSH2 gene than in those without hypermethylation (P = 0.038 and P = 0.004). The poor prognosis was still especially significant in adenocarcinoma (P = 0.035 and P = 0.061) and early-stage NSCLC patients (P = 0.067 and P = 0.041). CONCLUSION: Our data suggest that hMLH1 is the major altered mismatch repair gene involved in nonsmoking NSCLC tumorigenesis and that promoter methylation is the predominant mechanism in hMLH1 and hMSH2 deregulation. In addition, promoter methylation of the hMSH2 gene may be a potential prognostic factor in nonsmoking female lung cancer.  相似文献   
994.
曹漫明  张积仁  周媛  孙海  李工 《肿瘤》2005,25(6):555-558
目的研究核糖体蛋白基因在人卵巢癌顺铂耐药细胞中的表达.方法以顺铂为诱导剂,采用中等剂量、间歇作用法建立人卵巢癌顺铂耐药细胞系COC1/DDP,然后以其亲本细胞COC1为对照,应用cDNA微阵列检测COC1/DDP细胞的核糖体蛋白基因表达.结果与COC1细胞相比,COC1/DDP细胞对顺铂有6.2倍耐药性,细胞倍增时间延长了8.9 h,S期细胞减少了(27.4±2.13)%,而G1和G2期细胞分别增加了(19.6±3.71)%和(8.3±1.95)%.在143个表达水平发生改变的基因中,有12个核糖体蛋白基因表达下调,多个凋亡抑制基因表达上调,凋亡诱导基因CASP2表达下调.结论 COC1/DDP细胞对顺铂具有耐药性,耐药性的产生可能与部分核糖体蛋白基因的表达下调有关.  相似文献   
995.
乳腺癌survivin和TK1的表达及其与腋窝淋巴结转移的关系   总被引:3,自引:0,他引:3  
目的 探讨乳腺癌survivin蛋白的表达及其与肿瘤细胞增生和腋窝淋巴结转移的关系。方法收集乳腺癌60例,其中有腋窝淋巴结转移的28例,用免疫组化染色检测survivin和胞质胸腺嘧啶核苷激酶(cytosolic thymidinekinase,TK1)蛋白的表达情况。结果 ①乳腺癌组织中有survivin蛋白的表达,其阳性表达率为64.9‰②survivin蛋白表达阳性的乳腺癌细胞TK1的标记指数明显高于survivin蛋白表达阴性者。③无腋窝淋巴结转移的乳腺癌survivin蛋白阳性表达率明显低于有腋窝淋巴结转移者。结论 乳腺癌组织中有survivin蛋白的表达,且其表达与肿瘤细胞增生和腋窝淋巴结转移有关。  相似文献   
996.
目的:探讨三氧化二砷(Arsenic trioxide,As2O3)诱导尤文肉瘤细胞凋亡及对融合蛋白EWS—FLi1表达的影响,.方法:应用噻唑蓝(MTF)法、形态学观察、原位末端标记法(TUNEL)、流式细胞术(FCM)观察As2O3对体外生长的尤文肉瘤RD—ES细胞系生物行为的影响:应用半定量RT—PCR测定应用As2O3前后c—mye基因mRNA水平的变化;应用免疫细胞化学及固定化蛋白印迹法(Western blot)观察用药前后EWS—FLi1融合蛋白表达水平的变化、结果:As2O3对体外生长的RD—ES细胞系具有明显抑制作用,并可诱导细胞凋亡、c-mye基因mRNA表达水平和EWS—FLil融合蛋白表达量随As2O3作用时间延长逐渐降低结论:常规治疗浓度的As2O3对体外生长的尤文肉瘤细胞具有明显的杀伤作用,其作用机制与改变线粒体膜通透性和抑制EWS—Flil融合蛋白、降低c一myc基因表达有关。  相似文献   
997.
The aims were to determine the median survival and prognostic factors of patients with central nervous system (CNS) metastases managed with whole‐brain radiation therapy (WBRT), and to explore selection criteria in recently published clinical trials using aggressive interventions in CNS metastases. A retrospective audit was performed on patients managed with WBRT for CNS metastases. Potential prognostic factors were recorded and analysed for their association with survival duration. The proportion of patients with these factors was also compared with those of patients managed under three recently reported studies investigating aggressive interventions, such as radiosurgery and chemotherapy for CNS metastases. Seventy‐three patients were treated with WBRT for cerebral metastases over a 12‐month period. The median survival of the population was 3.4 months (95% confidence interval: 2.7–4.1), with 6‐ and 12‐month survival rates of 30 and 18%, respectively. Significant prognostic factors for prolonged median survival were Eastern Cooperative Oncology Group status 0–2 (P = 0.015), Medical Research Council neurological functional status 0–1 (P = 0.006), and Recursive Partitioning Analysis Class 2 versus Class 3 (P = 0.020). On multivariate analysis, younger patient age (P = 0.02) and better performance status (P < 0.01) were associated with improved outcome. When comparing these characteristics with selected published studies, our study cohort demonstrated a higher proportion of patients with poor performance status, a greater number of metastases per patient and a higher incidence of extracranial disease. This reflects the selected nature of patients in these published studies. Central nervous system metastases confer a poor prognosis and, for the majority of patients, aggressive interventions are unlikely to improve survival. The use of potentially toxic and expensive treatments should be reserved for those few in whom these studies have shown a potential benefit.  相似文献   
998.
替加氟又名喃氟啶,为氟尿嘧啶的衍生物,在体内经肝脏活化逐渐转变为氟尿嘧啶而起抗菌瘤作用.  相似文献   
999.
目的:观察并比较泮托拉唑与奥美拉唑治疗消化性溃疡的疗效和安全性.方法:将56例经内镜确诊的消化性溃疡患者随机分为两组,治疗组28例,静脉滴注泮托拉唑钠40 mg,对照组28例,静脉滴注奥美拉唑钠40 mg,均为2次/d,疗程3~5 d,此后两药均改口服,20 mg/次,1次/d,连续4周.结果:治疗后治疗组与对照组溃疡愈合率分别为76.9%和73.9%,总有效率分别为92.9%和96.4%,组间比较无显著性差异(P>0.05);两组不良反应均轻微.结论:泮托拉唑治疗消化性溃疡具有良好的疗效,值得临床推广应用.  相似文献   
1000.
正交试验法优选D-氨基半乳糖敏化小鼠的内毒素休克模型   总被引:2,自引:0,他引:2  
目的:建立D-氨基半乳糖敏化小鼠内毒素休克的规范化模型.方法:选择对内毒素休克小鼠死亡率有影响的3个因素:D-氨基半乳糖增敏剂量、内毒素攻击剂量及其给药途径,每个因素选取3个水平,按L9(34)正交试验表安排试验.以小鼠48 h死亡率为评价指标,并通过验证试验,优化与实验要求相符的造模条件.结果:各因素对动物死亡率影响程度依次为:D-氨基半乳糖增敏剂量>内毒素给药途径>内毒素攻击剂量.采用D-氨基半乳糖600 mg·kg-1敏化小鼠,腹腔注射内毒素0.5 mg·kg-1的给药方案为佳.结论:规范内毒素休克模型的复制条件,将有利于科学评价药物的抗内毒素活性.  相似文献   
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