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Objective To explore the effect of Fufangkushen on gastric cancer cell killing by human γδT cells. Methods Isopentenyl pyrophosphate method was used to amplify human peripheral blood γδT cells in vitro. Fufangkushen at various concentrations was used to induce γδT cells and gastric cancer cell lines SGC-7901 for 24 hours, MTr assays was used to detect inhibitory effect of Fufangkushen on these cell lines, LDH assays was used to measure the cytotoxic activity of γδT cells, and flow cytometry was used to detect apoptosis of γδT cells and SGC-7901 before and after the treatment. Results Ten days after cultivation, proliferation ra-tio of γδT cells increased from 4.21% to 70.35% and CD44 was up to 94.0%. Inhibitory rate of Fufangkush-en on SGC-7901 at various concentrations was significantly higher than that on γδT cells (22.3% vs-22.4%, P<0.05). The negative inhibitory ratio on γδT cells showed a dose-dependent manner with Fufangkushen's concentrations ranging from 1/5 to 1/400. γδT cells cytotoxic activity to SGC-7901 induced by Fufangkushen for 24 h was higher than control group, (83.6% vs 71.2%, P<0.05). Apoptotic rate was significantly lower in γδT cells than in SGC-7901 (4.64% vs49.23%, P<0.05). Conclusion Fufangkushen, within routine concentration ranges, can promote γδT cells' proliferation, inhibit tumor cell growth and enhance γδT cells' cytotoxic activity. This may be beneficial to tumor adoptive immunotherapy and provide evidence for the appli-cation of Fufangkushen in the treatment of tumors.  相似文献   
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Summary The in vitro growth requirements of three human embryonal carcinoma cell lines (H 12.7, 2102 EP, 1428 A) were investigated. The basal medium DME/F12 supplemented with insulin, transferrin, and low-density and high-density lipoproteins was sufficient to support substantial multiplication of all three lines. The most efficient attachment factor was either fibronectin (for 2102 EP and 1428 A) or collagen type I (H 12.7). In a serum-free system the influence of epidermal growth factor (EGF), insulin-like growth factor I, multiplication stimulating activity (MSA), a platelet extract, and the glucocorticoids dexamethasone and hydrocortisone, as determined by the DNA synthesis rate of the cells, was generally minimal. However, the DNA synthesis rate of cell lines H 12.7 and 2102 EP was increased by MSA, and the line with the highest potential to differentiate (H 12.7) was stimulated by EGF. All three cell lines secreted growth factors in a heterologous stimulation assay. Insulin-like growth factors I and II were not part of the growth promoting activity. The inhibitory effect of a monoclonal anti-EGF antibody on the 3H-thymidine incorporation of cell line 2102 EP might indicate autocrine secretion of EGF or an EGF-like factor by this cell line.  相似文献   
75.
Recent studies have shown the presence of receptors for granulocyte colony-stimulating factor (G-CSF) on lymphoid leukemic cells. To determine the effect of G-CSF on chemotherapeutic activity of cytosine arabinoside (Ara-C) on lymphoid as well as myeloid leukemic cells, we evaluated cell counts, apoptosis, and growth inhibition in HL-60, KG-1, Molt-4, Jijoye, and CCRF-CEM cell lines after incubation with Ara-C (0.1 and 1 micromol/L) and/or 5 ng/mL G-CSE G-CSF potentiated the effect of Ara-C on 2 of 3 lymphoid leukemic cell lines (Molt-4 and Jijoye), whereas it decreased the apoptosis and the effect of Ara-C on myeloid cell lines (HL-60 and KG-1).  相似文献   
76.
目的 研究异硫氰酸苄酯对人胶质瘤U87MG细胞体外侵袭和凋亡的影响,并初步探讨其作用机制。方法 采用MTS实验考察异硫氰酸苄酯对肿瘤细胞体外增殖的抑制作用;2,5 μmol·L-1异硫氰酸苄酯作用24 h后,采用Transwell实验、黏附实验和划痕实验观察异硫氰酸苄酯对人胶质瘤细胞侵袭、黏附和迁移能力的影响;应用Real-time-PCR和Western blot法检测相应浓度异硫氰酸酯处理后人胶质瘤U87MG细胞中MMP-2、MMP-9、CD44、Survivin、Bcl-2、Net1、RohA、caspase-3、caspase-8和p-AKT的表达变化;应用报告基因技术检测NF-κB转录活性的变化;采用ELISA法测定胞内8-OH-dG含量;10,20 μmol·L-1异硫氰酸酯作用24 h后,采用流式细胞术观察其对细胞凋亡的作用。结果 异硫氰酸苄酯可显著抑制人胶质瘤U87MG细胞体外增殖;与0 μmol·L-1组相比,2,5 μmol·L-1异硫氰酸苄酯对人胶质瘤细胞U87MG侵袭、黏附和迁移能力有明显的抑制作用;不同浓度异硫氰酸苄酯处理后,肿瘤细胞MMP-2、MMP-9、CD44、Survivin、Bcl-2、NET1和RhoA的mRNA和蛋白表达、AKT磷酸化水平和NF-κB转录活性明显下调,caspase-3和caspase-8表达以及8-OH-dG含量显著上调;10,20 μmol·L-1异硫氰酸苄酯可显著诱导细胞凋亡。结论 异硫氰酸苄酯抑制人胶质瘤细胞U87MG的侵袭能力,诱导细胞凋亡,其机制可能与抑制AKT/NF-κB信号转导途径,进而调节侵袭和凋亡相关基因表达有关。  相似文献   
77.
目的:通过体表测量计算胸腔容积评价肺发育、胸廓缩小程度及漏斗胸畸形程度。方法将90只健康4周龄SD大鼠分成实验组和对照组,实验组70只,对照组20只。实验组从胸骨旁切断下位3对肋软骨制作漏斗胸大鼠模型。分别于术前,术后2、4、8、12周测量胸部多条径线,并进行组间比较。胸腔容积大小用数学公式计算,利用阿基米德原理测量及C T三维重建所得,采用SPSS17.0进行 t检验及直线回归分析。结果实验采用多条径线测量结果,经过数学计算,阿基米德原理测量,以及CT三维重建所得结果实验组与对照组比较,差异有统计学意义(P<0.05)。结论通过体表测量计算胸腔容积的方法是可行的,该方法可替代CT检查对于评估漏斗胸形成过程中的胸腔容积的改变。  相似文献   
78.
张桃  谢铭  贺新媛  杨雪峰 《重庆医学》2015,(2):155-157,160
目的:建立人结肠癌鸡胚移植模型,研究龙葵碱对其血管生成的影响。方法将鸡胚分为对照组和低剂量组、中剂量组、高剂量组(均n=10),将培养的人结肠癌细胞系HT‐29细胞株接种到鸡胚绒毛尿囊膜(CAM)上,通过立体显微镜、Image‐proplus6.0图像分析软件及免疫组织化学苏木精‐伊红(HE)染色法,观察移植瘤在CAM上血管生成的特点,及不同龙葵碱剂量对血管生成的影响。结果HT‐29细胞接种到CAM第3~5天,大量血管向瘤体集中,长入或跨越瘤体表面,肿瘤迅速生长。给药后第5天进行拍照,图像分析,定量计算血管新生面积明显低于对照组,且呈剂量依赖性,各组间差异有统计学意义(P<0.01)。免疫组织化学检测表明不同剂量龙葵碱的微血管密度明显低于对照组,与血管新生面积相一致;ki‐67抗原表达指数逐渐下降,实验组低于对照组,且各组间差异有统计学意义(P<0.01)。结论龙葵碱能明显抑制人结肠癌HT‐29细胞株诱导的血管生成,从而抑制肿瘤的生长,为抗肿瘤血管生成的治疗方面提供了重要依据。  相似文献   
79.
Summary The BoLA phenotypes of lymphocytes from seven cattle have been compared with those of 19 lymphoblastoid cell lines derived from them by infection in vitro with either Theileria parva or T. annulata. Two long-established lines were also studied. In all cases except one, the BoLA phenotypes of the lymphoblastoid lines were identical with those of the original animal from whose lymphocytes they were derived. The one exception was a chimeric twin where a minor population appeared to have been transformed by T. parva. The antigens present on this line were present in the parents of the chimera, but not detectable in its own peripheral blood. The implications of these results as they relate to the use of these cell lines in immunizing cattle against East Coast fever and tropical theileriosis are discussed.  相似文献   
80.
Neoangiogenesis is essential for tumor and metastasis growth, but this complex process does not follow the same activation pathway, at least in tumor cell lines originated from different murine mammary adenocarcinomas. LMM3 cells were the most potent to stimulate new blood vessel formation. This response was significantly reduced by preincubating cells with indomethacin and NS-398, non-selective cyclooxygenase (COX) and COX-2 selective inhibitors, respectively. COX-1 and COX-2 isoenzymes were both highly expressed in LMM3 cells, and we observed that indomethacin was more effective than NS-398 to inhibit prostaglandin E2 (PGE2) synthesis. In addition, nitric oxide synthase (NOS) inhibitors, Nomega monomethyl L-arginine and aminoguanidine, also reduced LMM3-induced angiogenesis and nitric oxide (NO) synthesis as well. NOS2 > NOS3 proteins and arginase II isoform were detected in LMM3 cells by Western blot. The latter enzyme was also involved in the LMM3 neovascular response, since the arginase inhibitor, Nomega hydroxy L-arginine reduced the angiogenic cascade. On the other hand, parental LM3 cells were able to stimulate neovascularization via COX-1 and arginase products since only indomethacin and Nomega hydroxy L-arginine, which diminished PGE2 and urea synthesis, respectively, also reduced angiogenesis. In turn, LM2 cells angiogenic response could be due in fact to PGE2-induced VEGF liberation that stimulated neoangiogenesis at very low levels of NO.  相似文献   
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