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41.
目的:探讨磷脂酶Cε1(phospholipase C epsilon-1,PLCE1)在口腔鳞状细胞癌(OSCC)组织中的表达及其与临床病理特征和患者预后的关系。方法:应用免疫组织化学方法检测PLCE1在83例OSCC组织和20例正常口腔黏膜组织中的表达,并分析 PLCE1表达与OSCC临床病理特征的关系;采用Kaplan-Meier法进行生存分析,Cox 风险比例回归模型分析影响OSCC患者预后的独立因素。结果:PLCE1在OSCC组织与口腔正常黏膜组织中高表达率分别为53.01%和15.00%,差异有统计学意义(P=0.002)。PLCE1的表达与患者年龄、性别、吸烟无相关性,而与肿瘤分化程度、T分期、临床分期、N分期有密切关系。单变量分析显示临床分期、PLCE1、T分期、N分期是影响OSCC预后的因素,双变量分析显示PLCE1是其独立预后因素。结论:PLCE1过表达与OSCC的发生、发展密切相关,可作为判断OSCC恶性程度和不良预后的参考指标。  相似文献   
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Background and objectives: Laminin is a significant basement membrane (BM) glycoprotein, the expression ofwhich reflects BM integrity more precisely than do other ECM proteins. The present study aimed to evaluate lamininexpression in oral squamous cell carcinomas OSCC and to determine any associations with clinico-pathologicalparameters (surgical margin status, lymph node involvement, survival and recurrence). Methods: Laminin expression wasevaluated in 31 cases of biopsy-proven OSCC by immunohistochemical staining and its association with prognosticatorsand the Brynes grading system was determined by appropriate statistical analysis. Results: We observed a significantincrease in linear staining pattern (p<0.001) at the tumour-host interface in well-differentiated OSCC cases, in contrastto poorly differentiated lesions which exhibited intense cytoplasmic expression within tumour cells. Higher cytoplasmiclaminin expression was seen in 33.3% of cases with involved surgical margins and 69.2% of cases with lymph nodemetastasis (along with weak/absent staining of laminin around the tumour-host interface – Basement membrane aroundtumour islands). Similarly, in 60% of the cases who died and in 81.8% of cases with tumour recurrence, moderatelyintense cytoplasmic laminin expression was seen within tumour cells. On comparing variables of the Brynes gradingsystem, significant cytoplasmic expression of laminin was linked with mild inflammation (p<0.0016) and increasedmitotic activity (p<0.008). Conclusion: Based on these observations, immunohistochemical expression of lamininmight be useful to evaluate histological differentiation and aggressiveness of OSCCs.  相似文献   
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Introduction: Abnormal cell proliferation appears to be a possible predictor of tumorigenesis, Ki-67 proteinexpression is closely related to the cell proliferation and could be used as a biomarker for the growth in the most ofhuman tumors. The aim of the study: Investigating of Ki-67 expression in the pathological grades of oral epithelialdysplasia and oral squamous cell carcinomas. Materials and Methods: The sample consisted of 30 formalin-fixed,paraffin-embedded specimens of oral epithelial dysplasia (OED), 30 other of oral squamous cell carcinomas (OSCC), and10 normal oral epithelium (NOE) were conventionally stained with hematoxylin and eosin and immunohistochemicallystained with Ki-67 monoclonal antibody. Results: Expression of Ki-67 was restricted to the basal layers in the normaloral epithelium whereas Ki-67 positive cells in oral epithelial dysplasia (OED) were located in the basal, suprabasaland spinous layers, Ki-67 expression was increased in high-risk cases. Ki-67 positive cells in well-differentiated(OSCC) were located mainly in the periphery of the tumor nests, in moderately-differentiated (OSCC) were locatedin both peripheral and part of a center of the tumor nests whereas it was diffused in most of the Poorly-differentiated(OSCC). Statistical analysis indicated a significant difference between the expression in (OED) and (NOE), (OSCC)and (NOE), and no differences between (OED) and (OSCC). Conclusion: This study has concluded that Ki-67 antigencould be used as a marker for the histological grading of OED and OSCC, Expression of Ki 67 increased according tothe severity of oral epithelial dysplasia.  相似文献   
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目的 探讨凋亡相关基因caspase-3、caspase-9、Bax、Bcl-2在中国地鼠口腔正常黏膜、上皮单纯增生、上皮异常增生和鳞状细胞癌组织中的表达及其意义。方法 采用免疫组织化学法、RT-PCR检测正常中国地鼠口腔黏膜上皮、单纯增生上皮、异常增生上皮和鳞癌组织中caspase-3、caspase-9、Bax、Bcl-2蛋白及mRNA的表达。结果 在口腔黏膜癌变过程中,鳞癌组织中抑制凋亡蛋白Bcl-2表达明显高于口腔正常黏膜、上皮单纯增生、上皮异常增生(P<0.05);异常增生上皮caspase-3、caspase-9、Bax表达均明显高于正常组(P<0.05),但随着增生程度的加重,caspase-3、caspase-9、Bax表达明显降低(P> 0.05)。相关性分析显示,鳞癌组织中Bcl-2与Bax、caspase-3、caspase-9呈负相关(P< 0.05)。RT-PCR结果表明,与正常组织相比,鳞癌组织中Bcl-2高表达,而caspase-3、caspase-9、Bax的mRNA表达显著下调(P<0.05)。结论 本实验在中国地鼠鳞癌组织中caspase-3、caspase-9、Bax表达降低而Bcl-2表达上升,揭示了caspase-3、caspase-9、Bax、Bcl-2表达与口腔鳞癌的发生、发展密切相关,可以为口腔颊囊黏膜癌的基因治疗提供一些线索或并为评价OSCC的生物学特征及预后提供参考。  相似文献   
45.
PTEN、p27在口腔粘膜白斑和口腔癌组织中的表达及意义   总被引:1,自引:0,他引:1  
目的 探讨抑癌基因PTEN、p2 7在口腔粘膜白斑 (oralleukoplakia ,OLK)和口腔癌 (oralsquamouscellcancer,OSCC)组织中的蛋白表达及意义。方法 应用免疫组化S -P法检测 10例正常口腔粘膜、2 5例口腔粘膜白斑 (其中白斑伴上皮异常增生 15例 ,白斑不伴上皮异常增生 10例 )及 32例口腔癌组织中抑癌基因PTEN和p2 7的蛋白表达情况。结果 正常口腔粘膜和白斑不伴上皮异常增生组织中PTEN和 p2 7蛋白全部阳性表达 ;白斑伴上皮异常增生组织中PTEN和 p2 7蛋白阳性表达率分别为93.3%、73.3%。OSCC组织中PTEN蛋白阳性表达率为71.9% ,其中高、中、低分化OSCC组织中PTEN蛋白阳性表达率分别为 85 .7%、75 %和 33.3% ,统计学分析表明PTEN在OSCC组织中的蛋白表达与组织分化程度明显相关 (P <0 .0 5 )。OSCC组织中 p2 7蛋白的阳性表达率为4 0 .6 % ,其中高、中、低分化OSCC组织中p2 7蛋白的阳性表达率分别为 4 2 .9%、4 1.7%和 33.3% ,统计学分析表明p2 7在OSCC组织中的蛋白表达与组织分化程度无明显相关 (P >0 .0 5 )。结论 OSCC组织中PTEN和 p2 7蛋白的阴性表达率较高 ,说明PTEN和 p2 7基因突变或缺失在OSCC的发生发展过程中起重要作用。  相似文献   
46.
ObjectivesTo examine different immunophenotypes of cancer-associated fibroblasts (CAFs) in tongue squamous cell carcinoma (TSCC) and to investigate how they related to clinical outcomes.MethodsSerial sections from 54 cases of TSCC were immunohistochemically stained with α-smooth muscle actin (αSMA, CAF marker) to determine CAF density, and double-immunostained with αSMA combined with CD80 and CD86 (myeloid/monocytic-derived cell markers), Nanog (mesenchymal stem cell marker) and CD133 (hematopoietic/endothelial stem cell marker). Density of cells co-expressing these marker combinations was semi-quantitatively assessed in 5 randomly selected high power fields within the tumor area and scored as 1 – one-to-five stained cells in each field, 2 – more than 5 stained cells in each field; any finding less than score 1, was allocated a score of 0.ResultsThere were 26 CAF-poor, 16 CAF-rich and 12 CAF-intermediated cases. CD86+αSMA+ cells were the most frequent (80.4%) followed by CD80+αSMA+ (72%) and Nanog+αSMA+ cells (56%). The CD133+αSMA+ phenotype was found only in association with blood vessels. High density of αSMA+ CAFs was associated with disease recurrence and poor survival (p < 0.05). Increased density of CD86+αSMA+ cells was significantly associated with CAF-rich tumors and with poor survival (p < 0.05).ConclusionIn TSCC, CAFs demonstrate heterogeneous and overlapping phenotypes with the myeloid/monocytic type being the most frequent and having an impact on the clinical outcomes. Further studies are needed in order to further characterize CAF phenotypes in carcinomas of various oral sites, as this may open new frontiers for personalized medicine.  相似文献   
47.
Cisplatin (DDP) is a first-line chemotherapeutic drug applied for the treatment of oral squamous cell carcinoma (OSCC). The anticancer activity of DDP is tightly linked to its intracellular uptake. It is unwise to increase the DDP intake by increasing the dose or shortening the dosing interval because of the severe systemic toxicity (nephrotoxicity, ototoxicity and neurotoxicity) in DDP application. The main uptake pathways of DDP include passive diffusion and active transporter transport. Therefore, finding additional uptake pathways that can improve the effective intracellular concentration of DDP is critical. Macropinocytosis, an endocytic mechanism for extracellular material absorption, contributes to the intracellular uptake of anticancer drugs. No research has been conducted to determine whether macropinocytosis can augment the intracellular uptake of DDP in OSCC cells or not. Based on that, we proved for the first time that silmitasertib (previously CX-4945) could trigger macropinocytosis, which may increase the intracellular uptake of DDP and enhance apoptosis via in vivo and in vitro experiments. We hope that our findings will inspire a new approach for the application of DDP in cancer treatment.  相似文献   
48.
口腔黏膜癌变过程中中心体的扩增及其意义   总被引:11,自引:0,他引:11       下载免费PDF全文
目的 了解口腔黏膜癌变过程中中心体的状况,探讨中心体的异常在口腔鳞状细胞癌(OSCC)发生发展中的作用及其在口腔黏膜癌变过程中的意义。方法 选取正常口腔黏膜(12例)、轻度上皮异常增生(2例)、中度上皮异常增生(8例)、重度上皮异常增生(12例),口腔高分化鳞癌(10例)、中分化鳞癌(15例)、低分化鳞癌(7例)的石蜡包埋组织,采用间接免疫荧光双重染色(γ-微管蛋白单克隆抗体及细胞角蛋白多克隆抗体)显示上皮细胞中的中心体,分析其在口腔黏膜癌变过程中的变化趋势及在各组间的差异。结果 正常口腔黏膜上皮表现为大小数目正常的中心体,但在72·73%(16/22)的上皮异常增生及84·38%(27/32)OSCC组织中观察到部分上皮或肿瘤细胞中出现异常中心体,表现为中心体直径的增加或数目的增多。具有异常中心体的细胞数目随上皮异常增生程度的增加及肿瘤分化程度的降低而增加,二者存在明显的正相关关系(P<0·01)。结论 中心体的扩增是口腔黏膜癌变过程中的早期事件并与口腔癌发生发展进程有关,口腔黏膜癌变过程中的细胞形态学改变与中心体扩增之间可能存在直接机制上的联系。从调控中心体循环入手治疗口腔癌前病损及OSCC,有可能成为口腔癌预防和治疗的新途径。  相似文献   
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