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971.
To understand the molecular mechanisms of carcinogenesis of esophagus and to isolate genes with different expression levels in esophageal cancer, suppression subtractive hybridization (SSH) was combined with PCR-based cDNA synthesis and reverse Northern on the cancer tissues and matched almost normal mucosa using 5 microgram of total RNA as starting marterial. Eight genes were found expressed differentially in esophageal cancer, in which 5 were known genes and 3 were novel ones; and 6 were down-regulated in cancer tissues, while 2 were up-regulated; 6 were of mid-high abundance and 2 were of low abundance in esophagus. The results revealed that alteration in expression level of multiple genes underlied the initiation and development of esophageal cancer. The differentially expressed genes identified in this study such as liporcotinⅠ, cystatin A, cystatin B, cytokeratin 13 may play roles in dedifferentiation, transformation and malignant proliferation of esophageal cancer. The combination of SSH with PCR-based double- strand cDNA synthesis and high throughput reverse Northern screening is an efficient way to isolate differentially expressed genes from microgram of total RNA.  相似文献   
972.
To explore cell malignant phenotype correlated changes of cell surface adhesion molecules and cell-cell communication in carcinogenesis, human stomach transformed and cancer cell lines were investigated. Expressions of E-cadherin, N-cadherin,α-catenin, β-catenin as well as gap junction (GJ) protein Cx32 were studied by utilization of immunoblotting, immunocytochemical and fluorescent dye transfer methods. Mammalian normal stomach mucosal cells expressed E-cadherin but not N-cadherin. E-cadherin im-munofluorescence was detected at cell membranous adher-ens junctions (AJ) where colocalization with immunofluo-rescent staining of inner surface adhesion plaque proteins αnd β-catenins was observed. The existence of E-cadherin/ catenin (α-, β-) protein complexes as AJ was suggested. In transformed and stomach cancer cells E-cadherin was inhibited, instead, N-cadherin was expressed and localized at membranous AJ where co-staining with α- and β-catenin fluorescence was observed. Formation of N-cadherin/catenin (α-, β-) protein complex at AJs of transformed and cancer cells was suggested. The above observations were further supported by immunoblotting results. Normal stomach muscosal and transformed cells expressed Cx32 at membranous GJ and were competent of gap junction communication (GJIC). In stomach cancer cells, Cx32 was inhibited and GJIC was defective. The results suggested that changes of signal pathways mediated by both cell adhesion and cell communication systems are associated intracellular events of stomach carcinogenesis. The alteration of cadherin isoform from E- to N-cadherin in transformed and stomach cancer cells is the first report.  相似文献   
973.
探讨Ⅰ、Ⅱ期宫颈癌淋巴结转移相关因素。回顾性地分析590例行广泛性全子宫切除及盆腔淋巴结清扫术的Ⅰ、Ⅱ期宫颈癌患者的临床分期及病理资料。将盆腔淋巴结转移与各临床参数的关系进行统计学分析。结果Ⅰ、Ⅱ期宫颈癌盆腔淋巴结总的转移率为20.34%,年龄、临床分期、肿瘤直径、肿瘤生长方式、肿瘤组织学分级、肌层浸润深度、脉管浸润、阴道切缘受累均与盆腔淋巴结转移相关,而病理类型、术前放化疗与盆腔淋巴结转移无关。结论:年龄越轻,临床期别越晚,肿瘤直径越大,浸润深度越深,溃疡型肿瘤病理分化越差,阴道切缘受累,伴有脉管浸润者,盆腔淋巴结转移率就越高。  相似文献   
974.
利用DPPH自由基清除能力与总还原能力分析,对新疆产细虫草发酵菌丝体的菌醇提物(OGPDC)的抗氧化能力进行测定.MTT分析OGPDC对肺癌A549细胞增殖的抑制作用.抗氧化结果表明OGPDC具有较好的清除DPPH自由基及总还原能力,且清除自由基和总还原能力随着醇提物浓度的升高,逐渐增强,清除DPPH自由基的IC50值为1.952 mg/mL;MTT结果显示OGPDC对肺癌A549细胞增殖有一定的抑制作用,随着浓度提高而增强,处理48 h时药物的IC50值为10.87 μg/mL.另外,利用用流式细胞仪检测OGPDC作用48 h后肺癌A549细胞周期变化及凋亡率,其总凋亡率高于仅加培养液的对照组,最高总凋亡率为34.77%,使A549细胞周期阻滞在G0/G1期.结果表明新疆产细虫草菌醇提物(OGPDC)在一定的浓度范围内具有抗氧化及抗癌活性,暗示新疆产细虫草发酵菌丝体具有重要的开发利用价值.  相似文献   
975.
摘要: 目前,对癌症的治疗除采取手术和化疗方法外,还没有发现可靠的治疗方法。科学研究表明,CTLA-4 和 PD-1是体内的两种蛋白,他们能抑制免疫系统发挥免疫攻击能力,从而导致肿瘤的形成。通过针对这两种蛋白制 备的单克隆抗体,可以破坏他们的抑制作用从而激活免疫系统,发挥抗肿瘤生长作用。此外,通过对 T 细胞进行基 因修饰可以使其将肿瘤细胞作为靶细胞。这种免疫疗法可被用于癌症的治疗并且已经取得了初步的成功。本文对以上两种方法的基本情况作了简要论述。为该领域的研究实践提供一定的参考。  相似文献   
976.
介绍了最优分类超平面的概念和构建最优分类超平面的方法,并将其应用于乳房肿瘤的分类问题,还给出了相应的计算结果.  相似文献   
977.
目的研究参术胶囊对脾虚胃癌转移鼠动物模型胃癌细胞形态的影响,探讨参术胶囊抗脾虚胃癌转移的作用机理。方法在建立裸鼠脾虚胃癌转移病证结合动物模型基础上,采用HE染色方法研究参术胶囊对脾虚胃癌转移鼠动物模型癌细胞分化的影响。结果参术胶囊对胃癌组织细胞分化有明显调控作用。结论参术胶囊具有改善瘤细胞的异型性,诱导胃癌组织细胞重新分化的作用,这可能是参术胶囊抗脾虚胃癌转移的作用机制之一。  相似文献   
978.
探讨Sp1调控转录因子FoxM1在卵巢癌中的表达。免疫组织化学染色验证FoxM1在卵巢癌组织中高表达,Spearman'rho秩相关分析Sp1与FoxM1在卵巢癌组织中的表达相关性;双荧光素酶报告系统检测Sp1对FoxM1的调控作用;Real-time quantitative RT-PCR和蛋白免疫印迹技术验证Sp1对FoxM1的调控作用。FoxM1在大于60%的卵巢癌组织中呈阳性表达(阳性率33/42≈79%),并且与Sp1的表达显著相关(r=0.809,P0.01);Sp1可以结合并激活Foxm1启动子(P0.05);上调Sp1表达可以激活FoxM1在卵巢癌中的表达(P0.05),而干扰Sp1后可以下调FoxM1的表达(P0.05)。Sp1参与调控增殖相关转录因子FoxM1在卵巢癌中的表达。  相似文献   
979.
为了提高诊断正确率,大量医学研究集中于探讨肿瘤标志物正常值与非正常值的合适划分,即确定分割点。为此,该文提出了一种肿瘤标志物多分割点设置算法。通过正交实验和缩小搜索空间的方法,进一步提高了诊断正确率和优化收敛速度。在结直肠癌实际诊断数据中的应用效果表明,该算法能有效地提高诊断正确率,其诊断结果优于医学上的单分割点的诊断结果。  相似文献   
980.
Methoxyl poly (ethylene glycol) (mPEG-OH) was successfully grafted onto branched polyethyleneimine (hy-PEI) to yield a water soluble graft copolymer mPEG-g-PEI. This copolymer may package superparamagnetic iron oxide (SPIO) by ligand exchange. The SPIO weight percentage in the polymer coated nanoparticles was determined to be 55%, the size and zeta potential of nanoparticles was 50 nm and 12 mV respectively. Antibody fixation onto the complex (mPEI-g-PEG-SPIO) surface layer was achieved by activated single chain monoclonal antibody against prostate stem cell antigen (PSCA). Our study showed that the single chain antibody functionalized nanoprobe (scAbpscA-PEI-g-PEG-SPIO) with a small size can specifically enter the prostate cancer cells, decreasing MRI T2-weighted signal intensity of prostate cancer cells to 44.76%, Our results revealed that the potential of this magnetic nanoparticulate system promised as a novel MRI nanoprobe for early diagnosis of prostate cancer (PCa).  相似文献   
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