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991.
大肠癌是最常见的消化系恶性肿瘤之一,近年来其发病率有逐年上升趋势。大肠癌的治疗关键在于早期诊断,而目前惟一的根治方法是早期切除肿瘤。癌相关基因(CAGE)是2002年发现的与癌症有关的基因,其在多种癌组织及肿瘤细胞系中呈高表达,在除睾丸组织外的正常组织中均无表达。现回顾性分析大肠癌、大肠腺瘤及正常黏膜组织中CAGE的表达及其启动子低甲基化情况。  相似文献   
992.
大肠癌目前的治疗手段仍是以手术切除为主的综合治疗 ,术后 5年生存率约 5 0 %左右 ,约半数的患者在术后出现转移和复发 ;除部分早期患者外 ,晚期和手术切除后的患者均需接受化疗。大肠癌患者的化疗 ,主要适用于 :1术前化疗 ,又称新辅助化疗 ,其目的在于术前用药使肿瘤细胞变性坏死 ,缩小肿瘤体积 ,纤维化 ,减少肿瘤与周围组织的侵犯粘连 ,提高切除率 ;杀灭入侵血道、淋巴道的游离癌细胞 ,预防术后发生转移 ;彻底杀灭手术难以发现与清除的亚临床病灶 ,减少复发。2根治术后辅助化疗 ,预防术后复发和转移 ,延长生存期。3晚期姑息化疗 ,用于晚…  相似文献   
993.
中国大肠癌研究进展   总被引:14,自引:14,他引:14  
大肠癌(colorectal cancer,CRC)是我国位居第4位的常见恶性肿瘤,其发病率和死亡率有逐年增高的趋势,发病年龄也明显提高。大规模的人群普查研究表明,35岁以上的人群中,大肠癌的发病率约为24~32例/10万人口。随着分子生物学、遗传学和生物技术的发展,近几年来我国在大肠癌的基础、临床和预防方面的研究取得了较大的进展,现简单介绍如下。 1 基础研究 1.1 发生机制目前已明确,大肠癌的发生受到遗传和环境因素的作用,涉及多个癌基因和抑癌基因的改  相似文献   
994.
大肠侧向发育型肿瘤临床意义及诊治   总被引:4,自引:0,他引:4  
背景:火肠侧向发育型肿瘤(LST)是指起源于人肠粘膜的一类隆起型病变,这类病变极少向肠壁深层垂直侵犯,而主要沿枯膜表面呈侧向浅表扩散,故称之为侧向发育型肿瘤。大肠侧向发育型肿瘤(LST)其病变形态和发生发展上有一定的特殊性,不同于一般的腺瘤,LST与大肠癌的关系密切,并已有动态观察表明LST病变可以在3年内发展为进展期大肠癌。方法:应用放大内镜及粘膜染色方法在近一年共共检查2920名患。结果:发脱25例侧向发育型肿瘤,共26个病变。其中颗粒均一型11例,结节混合型15例,粘膜内确3例,锯齿状肿瘤2例;病变最大为60X72mm,最小为llXl2ram:11~20mm有6个:21-30mm:9个:31mm以上有11个病变。在26例病变中,腺管开口类型主要以Ⅳ型腺管开口为主,占61.54%(16/26);表现为VA型腺管开口的LST的3例患,病理诊断为粘膜内癌,7例表现为ⅢL型腺管开口类型的病例,病理诊断为管状绒毛状腺瘤;26例病变全部在发现病变的同时或择期进行EMR或EPMR切除治疗。全部病例未发生任何出血或穿孔等并发症。结论:对LST的临床检出必须应用粘膜染色技术和放大内镜,对有肠道粘膜发红或粗糙、血管网不清或消失的征象必须进行粘膜染包,以发现病变。LST的腺管开口大多数表现为Ⅳ型或ⅢL型,而Ⅳ型腺管开口多为绒毛状腺瘤,ⅢL型腺管开口多为管状腺瘤,一但出现Ⅴ型腺管开口则已经表明有癌变变发生。  相似文献   
995.
AIM: To evaluate the efficacy and the safety of combined 5-Fluorouracil, irinotecan, bevacizumab and sirolimus in refractory advanced colorectal carcinoma. METHODS: We initiated a regimen with at day 1 an injection (iv) of bevacizumab at 5 mg/kg, followed by 180 mg/m^2 irinotecan, followed by Leucovorin 400 mg/m^2, followed by a 5-Fluorouracil bolus 400 mg/m^2 and a 46-h infusion 2400 mg/m^2. Sirolimus was given orally as continuous administration of 2 mg twice a day every days. This treatment was repeated every 14 d. RESULTS: A total of 12 patients were enrolled. All patients presented with metastatic disease that had failed at least three lines of chemotherapy that contained oxaliplatin, irinotecan and bevacizumab. Cetuximab failure was also observed in all K-Ras wildtype patients. The median number of cycles was 8.5 (range 2-20) and clinical benefit was observed in eight patients. The median time to progression was 5 mo and the median survival was 8 too. Grade 3 neutropenia developed in four patients, and grade 3 diarrhea and stomatitis in two.CONCLUSION: The combination regimen of 5-Fluorouracil,irinotecan, bevacizumab and sirolimus in advanced colorectal carcinoma after failure of dassical be.absent is feasible and promising. Further evaluation of this combination is required.  相似文献   
996.
本组有168例大肠腺瘤,癌变18例,癌变率为10.7%。本文将临床与病理结合起来,并联系文献分析大肠腺瘤与大肠癌之间的内在关系,以寻求一条早期诊断及治疗大肠癌的途径。 1 对象和方法 本文调查了我院近10年来行结肠镜检查的2051例患者,发现癌变18例。癌变病例中,男6例,女12例,年龄30—67岁,左半结肠17例,右半结肠(横结肠)1例。瘤体大小:>2cm 16例,<2cm 3例。将2051病例分为腺瘤性息肉组168例和非腺瘤性息肉组264例。根据年龄影响腺瘤的非典型增生率,又将腺瘤性息肉组病例分为35岁以下及  相似文献   
997.
Tumor-host interaction at the invasive front of colorectal cancer represents a critical interface encompassing a dynamic process of de-differentiation of colorectal carcinoma cells known as epithelial mesenchymal transition (EMT). EMT can be identified histologically by the presence of "tumor budding", a feature which can be highly specific for tumors showing an infiltrating tumor growth pattern. Importantly, tumor budding and tumor border configuration have generated considerable interest as additional prognostic factors and are also recognized as such by the International Union Against Cancer. Evidence seems to suggest that the presence of tumor budding or an infiltrating growth pattern is inversely correlated with the presence of immune and inflammatory responses at the invasive tumor front. In fact, several tumor-associated antigens such as CD3, CD4, CD8,CD20, Granzyme B, FOXP3 and other immunological or inflammatory cell types have been identified as potentially prognostic in patients with this disease. Evidence seems to suggest that the balance between pro-tumor(including budding and infiltrating growth pattern) and anti-tumor (immune response or certain inflammatory cell types) factors at the invasive front of colorectal cancer may be decisive in determining tumor progression and the clinical outcome of patients with colorectal cancer. On one hand, the infiltrating tumor border con-figuration and tumor budding promote progression and dissemination of tumor cells by penetrating the vascular and lymphatic vessels. On the other, the host attempts to fend off this attack by mounting an immune response to protect vascular and lymphatic channels from invasion by tumor buds. Whereas standard pathology reporting of breast and prostate cancer involves additional prognostic features, such as the BRE and Gleason scores, the ratio of pro- and anti-tumor factors could be a promising approach for the future development of a prognostic score for patients with colorectal cancer which could complement tumor node metastasis staging to improve the clinical management of patients with this disease.  相似文献   
998.
Colorectal cancer (CRC) is the second most freq uent malignant disease in Europe. Every year, 412 000 people are diagnosed with this condition, and 207 000 patients die of it. In 2003, recommendations for screening programs were issued by the Council of the European Union (EU), and these currently serve as the basis for the preparation of European guidelines for CRC screening. The manner in which CRC screening is carried out varies significantly from country to country within the EU, both in terms of organization and the screening test chosen. A screening program of one sort or another has been implemented in 19 of 27 EU countries. The most frequently applied method is test - ing stool for occult bleeding (fecal occult blood test, FOBT). In recent years, a screening colonoscopy has been introduced, either as the only method (Poland) or the method of choice (Germany, Czech Republic).  相似文献   
999.
AIM: To evaluate the efficacy and complications of stereotactic body radiotherapy in localized paraaortic lymph node recurrence from colorectal cancer. METHODS: From 2003 to 2009, 7 patients with paraaortic lymph node recurrence (1-3 lesions) from colorectal cancer were treated with stereotactic body radiotherapy. Total gross tumor volumes ranged from 4 to 40 mL. The doses were escalated from 36 Gy/patient to 51 Gy/patient and were delivered in 3 fractions. RESULTS: One and 3 year overall survival rates were 100% and 71.4%, respectively, and median survival was 37 mo. Grade Ⅳ intestinal obstruction was reported in 1 of 7 patients. This patient received 48 Gy in 3 fractions with a maximum point dose to the intestine of 53 Gy and V_(45Gy) = 3.6 mL. However, 6 patients received an intestinal maximum point dose of < 51 Gy and V_(45Gy) of < 1 mL, and did not develop any severe complications. CONCLUSION: This pilot study suggests selected paraaortic lymph node recurrence (1-3 closed lesions) that failed to respond to chemotherapy can be potentially salvaged by stereotactic body radiotherapy.  相似文献   
1000.
分子靶向治疗为大肠癌的治疗提供了新的手段,它能够特异性地作用于肿瘤发生发展中起关键作用的靶分子及其调控的信号传导通路,从而达到治疗肿瘤的目的。在肿瘤分子靶向治疗的临床试验中,表皮生长因子受体(EGFR)拮抗剂对大肠癌的药物治疗已经显示出了潜在的疗效和良好的发展前景。本文拟就其理论基础及临床研究进展做一回顾。  相似文献   
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