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1.
目的:分析T1期(肿瘤直径<2cm)原发性乳腺癌女性患者绝经前后在肿瘤大小、病理分类、淋巴结转移率和数目。方法:常规病理检验以及应用免疫组化、HE法分别测定绝经前乳腺癌患者和绝经后乳腺癌患者者的ER、PR。结果:两组患者在肿瘤大小上无明显差异,但绝经前乳腺癌患者浸润导管癌的百分比为 84. 7%,绝经后乳腺癌患者的浸润导管癌百分比为 62. 2%,经χ2 检验,P<0. 01。两组淋巴结转移率分别为 39. 3%和 25. 5%,经χ2 检验,P<0. 01。两组ER和PR阳性伴淋巴结转移的比例经χ2 检验,P<0. 05。结论:绝经前乳腺癌患者和绝经后乳腺癌患者在病理分类、淋巴结转移率及数目、ER、PR阳性伴淋巴结转移上有显著性差异。对于T1原发性乳腺癌患者不论有无淋巴结转移,均应行癌肿切除伴Ⅰ、Ⅱ级淋巴结清扫。  相似文献   
2.
THESTUDYOFESTROGENANDPROGESTERONERECEPTORINNASOPHARYNGEALCARCINOMAZhengTianrong郑天荣;LiJiancheng李建成;LiuXiuying刘秀英;(Departmentof...  相似文献   
3.
槐耳清膏治疗肝癌的实验研究   总被引:10,自引:0,他引:10  
目的 探讨槐耳清膏对人胎脐静脉内皮细胞的作用 ,以及其对裸鼠皮下接种肝癌细胞形成肝癌的抑制作用及其可能机制。方法 用不同浓度的槐耳清膏作用于人胎脐静脉血管内皮细胞 ,观察其对细胞的增殖能力、迁移能力、附壁能力及血管生成的影响 ,同时观察其对裸鼠皮下接种肝癌细胞形成肝癌过程的影响。结果 槐耳清膏≥ 2mg/ml时可显著降低肿瘤组织的血管内皮细胞增殖能力 ,减少血管形成 ,抑制血管内皮细胞的迁移、黏附 ,从而降低微血管密度。槐耳清膏 ( 3g/kg) MMC( 5 0 0 μg/kg)同时作用于裸鼠的肝癌组织 ,其抑瘤作用最强 ,后依次为MMC组 ,槐耳清膏 ( 3g/kg)组。结论 槐耳清膏对肝癌有抑制作用 ,其可能机制是作用于血管内皮细胞 ,影响血管内皮细胞的增殖能力、迁移能力、附壁能力及血管生成 ,从而抑制肝癌组织的血管生成 ,降低肝癌组织的微血管密度而发挥抑制肝癌生长的作用  相似文献   
4.
Summary At clinical presentation, the majority of malignant tumors are composed of multiple clonal subpopulations of tumor cells with different phenotypic characteristics. Using the experimental tumor model ER 15-P, a methylcholanthrene-induced pleomorphic sarcoma of the C57 Bl6J mouse, we studied a system of long-term in vivo passages of this primary tumor for cell morphological changes, and alterations in the potential for spontaneous lung metastases. Transplants from the primary after the 4th, 20th, 40th and 80th i.m. passage (referred to as T4, T20, T40, and T80 respectively) together with their lung metastases were investigated by light microscopy, immunohistochemistry, and electron microscopy. In addition, the potential for metastasis to the lungs in each group was determined and compared with that of the parent T4 tumors. T4 tumors were mainly composed of spindle-shaped tumor cells with the ultrastructural features of fibroblasts and myofibroblasts, often arranged in a storiform or fasciculated growth pattern, and intermingled with tumor giant cells. Some small areas contained polygonal or rounded tumor cells, ultrastructurally undifferentiated, and sometimes arranged in a hemangiopericytoma-like growth pattern. Although electron-microscopical findings clearly demonstrated the mesenchymal origin of these tumor cells, immunostaining with a polyclonal antibody to vimentin was unspecific in all tumor cells and normal mouse tissue. Monoclonal antibodies to vimentin from different sources were completely negative in tumor cells and murine stromal components. In contrast, myofibroblast-like tumor cells showed immunohistochemically, a moderate to strong co-expression with monoclonal antibodies to desmin, muscle actin and ER="0">-smooth muscle actin. On the basis of these morphological findings, the primary ER 15-P was classified as a pleomorphic myofibrosarcoma. The lung metastases of T4 tumors were mainly composed of undifferentiated round to polygonal tumor cells, while the number of desmin-positive, muscle- and ER="0">-smooth muscle-actin-positive cells was reduced. The morphological features of T20 tumors and their lung metastases were the same as in T4, indicating a relative stability of the phenotype up to that stage. In contrast, T40 and T80 tumors and their lung metastases were found to contain almost exclusively undifferentiated tumor cells and many tumor giant cells. While fibroblast-like tumor cells were seen only occasionally, myofibroblast-like tumor cells had almost completely disappeared. The potential for lung metastases was nearly constant in all groups, suggesting metastatic stability. Obviously, the undifferentiated tumor cells of this model are associated with a higher metastatic potential.Abbreviations T4, T20, T40, T80 transplants from the primary tumor after the 4th, 20th etc. i.m. passage - MFH malignant fibrous histiocytoma  相似文献   
5.
A number of metabolites of 17beta-estradiol were tested for their estrogenic activity using the ER-CA-LUX assay based on the increased expression of luciferase in exposed T47D breast cancer cells. E2beta and estrone showed similar potencies in the test, whereas E2alpha was 100 times less active. Incubation of cells with estrone (0.35 microM) resulted in the formation of E2beta, whereas the reverse reaction was observed for E2beta. The resulting equilibrium may explain the similar estrogenic potency of estrone in the test. The synthetic 17-hydroxy benzoate ester of E2beta was 3 times less active than the parent compound. The 17-hydroxy palmitate and oleate esters of E2beta, were respectively 25 and 200 times less active than the parent compound. The 2-hydroxy metabolites of E2beta and estrone showed a 5,000 to 10,000 fold lower activity. The 4-hydroxy metabolites were more potent than the 2-hydroxy metabolites, showing only a 20-200 times lower activity. The 2- and 4-methoxyesters of estrone were 700 times less active. It is concluded that the estrogenic potency of metabolites formed in cattle after treatment with E2beta, like estrone, E2alpha and especially the esters of E2beta, may be significant with respect to the potential risk of the use of estradiol for growth promotion in domestic animals in certain countries.  相似文献   
6.
ER chaperone functions during normal and stress conditions   总被引:8,自引:0,他引:8  
  相似文献   
7.
Mice expressing transgenic T cell receptors (TCR) are used to explore important questions in immunity. However, transgene expression may have unexpected effects. We previously reported a B cell immunodeficiency, comprising decreased B cell numbers and diminished antibody responses, in mice that express a transgenic TCR specific for nicotinic acetylcholine receptor; the mice were generated using cassette vectors designed specifically for transgenic TCR expression [see Kouskoff et al. J. Immunol. Methods 1995. 180: 273-280]. We now show data suggesting that this defect is due to the expression and accumulation of TCR alpha and beta chains inside B cells and induction of an endoplasmic reticulum stress response, causing apoptosis at the pre B-I and later B cell stage. Thus, inappropriate transgene expression can profoundly affect B cells, leading to a previously undescribed mechanism of immunodeficiency.  相似文献   
8.
目的:对比氨氯地平与非洛地平缓释剂治疗轻中度原发性高血压的疗效和安全性;每日1次服药对24小时动态血压的影响;并对比药物漏服对血压控制的影响。方法:76例轻、中度高血压患者被随机、双盲分成两组,分别每日口服1次氨氯地平5~10mg(Ⅰ组)或非洛地平缓释剂5~10mg(Ⅱ组),治疗12周,并用24小时动态血压监测评价用药前后24小时血压变化情况及漏服48小时的血压变化。结果:氨氯地平治疗组舒张压降低15.1mmHg(治疗末为84.8mmHg),非洛地平缓释剂治疗组舒张压降低15.3mmHg(治疗末为85.0mmHg)。总有效率Ⅰ组病人为83.8%,Ⅱ组为87.9%(P=NS)。在药物的初始剂量下即能达到有效血压控制的病人数Ⅰ组为76%,Ⅱ组为52%(P<0.01)。药物漏服24和48h后,Ⅰ组临床血压仍低于140/90mmHg,24小时动态血压与漏服前相比无显著性差异,而Ⅱ组的临床血压高于140/90mmHg,临床血压和24小时动态血压与漏服前相比具有显著性差异。两治疗组的副作用发生率均较低。结论:氨氯地平与非洛地平缓释剂均能有效降低轻、中度高血压病人的血压,安全、疗效可靠,病人耐受性好,但漏服试验表明漏服24与48h氨氯地平仍能较好的控制血压。Ⅰ组的血压波动明显低于Ⅱ组。  相似文献   
9.
胃癌及癌前病变组织中雌激素受体和P21ras的表达及意义   总被引:1,自引:0,他引:1  
目的 探讨雌激素受体(ER)和ras原癌基因蛋白-P2ras的表达在胃癌发生、发展中的作用及与胃癌生物学行为的关系。方法 采用免疫组化SP法。结果 ER在慢性浅表性胃炎(20例)、异型增生(21例)中均为阴性,胃癌(40例)的表达阳性率为40%,三组比较有显著性差异(I〈0.05)。P21^ras在慢性浅表性胃炎、异型增生、胃癌的表达阳性率分别为10%、23.8%、47.5%,三组比较差异有显著性  相似文献   
10.
目的 探讨促性腺激素释放激素激动剂(GnRHa)对子宫肌瘤内雌、孕激素受体(ER、PR)、表皮生长因子受体(EGF-R)的影响。方法 测定13例子宫肌瘤患者经GnRHa治疗3月后肌瘤内雌、孕激素受体和EGF-R水平,并以28例未用药肌瘤作对照。结果  GnRHa治疗组肌瘤内ER、PR、EGF-R水平明显低于对照组。结论 GnRHa除减少肌瘤内ER、PR外,使肌瘤内EGF-R的水平下降可能是GnRHa治疗子宫肌瘤的一个重要机制。  相似文献   
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