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81.
口腔鳞癌中D2-40表达的特点及临床意义 总被引:1,自引:0,他引:1
目的探讨口腔鳞癌组织中淋巴管分布、密度及其与临床病理因素之间的关系。方法应用免疫组化SP法检测口腔癌D2-40的表达情况,计数淋巴管密度(lymphatic vessel density,LVD),分析其与临床病理特征间的关系。结果口腔鳞癌中的淋巴管形态及分布在不同区域具有异质性。与肿瘤中心(肿瘤实质)及癌旁正常组织比较,肿瘤边缘区(肿瘤间质)的淋巴管LVD为(11.09±2.958),显著高于肿瘤中心(5.81±1.334)及癌旁正常组织(4.96±1.716),且形态多呈扩张状态。结论口腔鳞癌中的淋巴管主要位于肿瘤边缘区,肿瘤边缘区LVD与淋巴结转移状态相关,检测口腔癌边缘区的LVD对预测是否发生淋巴结转移可能具有重要意义。 相似文献
82.
LCM联合快速免疫组化技术——一种获取肿瘤原位血管内皮细胞的可行途径 总被引:1,自引:0,他引:1
目的肿瘤血管内皮细胞对肿瘤发生发展极为重要,是目前肿瘤研究的热点。本研究为从肿瘤组织原位获取高纯度血管内皮细胞进行基因表达研究摸索可行方法。方法获取淋巴瘤组织标本后,置于锌固定液中固定,并通过进行激光捕获显微切割(lasercapture microdissection,LCM)前操作模拟LCM环境,确定锌固定法对RNA完整性的保护作用。将组织标本制作冰冻切片,采用快速免疫组化染色方法标记血管内皮细胞,利用LCM技术获取肿瘤组织原位血管内皮细胞,并用RT-PCR方法对所获细胞进行纯度检测。结果无论是固定后直接提取组织RNA,还是经模拟LCM环境再提取RNA,均显示锌固定法对RNA完整性提供了良好保护。快速免疫组化可以明确标记血管内皮细胞,后者能够被LCM准确捕获,并经RT-PCR验证为高纯度的血管内皮细胞。结论快速免疫组化联合LCM技术可以从肿瘤组织原位获取高纯度血管内皮细胞,并保证RNA的完整性,可能为肿瘤血管内皮细胞基因表达研究奠定基础。 相似文献
83.
84.
目的探讨PDCA循环在提高肿瘤患者输液港护理依从性的应用效果。方法选取2018年2~8月我院收治的504例输液港置管的肿瘤患者按随机分配原则分为对照组240例和观察组264例,对照组给予一般治疗和常规管理,观察组在对照组基础上实施PDCA循环管理,观察两组患者的并发症发生情况、输液港护理依从性,并进行统计分析。结果观察组的并发症发生率明显低于对照组,差异有统计学意义(P<0.05);观察组的输液港护理依从性明显高于对照组,差异有统计学意义(P<0.05)。结论运用PDCA循环能优化维护流程,降低并发症,提高患者输液港护理依从性,值得临床应用。 相似文献
85.
More than 10 years have passed since the discovery of the second estrogen receptor, estrogen receptor β (ERβ). It is now evident that ERα is not the only ER in breast cancer cells; in fact, ERβ is expressed in the majority of breast cancers although at lower levels than in the normal breast. In addition, ERβ is expressed in breast cancer infiltrating lymphocytes, fibroblasts and endothelial cells, all known to influence tumor growth. By overexpressing or knocking-out ERβ in breast cancer cell lines, several researchers have investigated its function with respect to proliferation and tumor growth. It appears that ERβ is anti-proliferative, in many ways antagonising the function of ERα. Furthermore, phytoestrogens have a binding-preference for ERβ and several epidemiological studies indicate a breast cancer preventing effect of this class of compounds. Tamoxifen is one of the standard, adjuvant treatments for ERα positive breast cancer, classically thought to mediate its effect through ERα. However, in several recent studies, ERβ has been described as a potential marker for tamoxifen response. In summary, experimental, epidemiological as well as diagnostic studies point towards ERβ as an important factor in breast cancer, opening up the possibility for novel ERβ-selective therapies in the treatment of breast cancer. 相似文献
86.
A fish antimicrobial peptide, tilapia hepcidin TH2-3, shows potent antitumor activity against human fibrosarcoma cells 总被引:2,自引:0,他引:2
As part of a continuing search for potential anticancer drug candidates from antimicrobial peptides of marine organisms, tilapia (Oreochromis mossambicus) hepcidin TH2-3 was evaluated in several tumor cell lines. The results indicated that TH2-3, a synthetic 20-mer antimicrobial peptide, specifically inhibited human fibrosarcoma cell (HT1080 cell line) proliferation and migration. The way in which TH2-3 inhibited HT1080 cell growth was then studied. TH2-3 inhibited HT1080 cell growth in a concentration-dependent manner according to an MTT analysis, which was confirmed by a soft-agar assay and AO/EtBr staining. Scanning electron microscopy revealed that TH2-3 caused lethal membrane disruption in HT1080 cancer cells, and a wound healing assay supported that TH2-3 decreased the migration of HT1080 cells. In addition, c-Jun mRNA expression was downregulated after treatment with TH2-3 for 48–96 h compared to the untreated group. These findings suggest a mechanism of cytotoxic action of TH2-3 and indicate that TH2-3 may be a promising chemotherapeutic agent against human fibrosarcoma cells. 相似文献
87.
Allal Ouhtit Rajiv L. Gaur Zakaria Y. Abd Elmageed Augusta Fernando Rajesh Thouta Alison K. Trappey Mohamed E. Abdraboh Hassan I. El-Sayyad Prakash Rao Madhwa G.H. Raj 《生物化学与生物物理学报:癌评论》2009
CD146, also known as melanoma cell adhesion molecule or MCAM, is a key cell adhesion protein in vascular endothelial cell activity and angiogenesis. CD146 promotes tumor progression of many cancers including melanoma and prostate. Strikingly, its expression is frequently lost in breast carcinoma cells, and it may act as a suppressor of breast cancer progression. While upstream mechanisms regulating CD146 are well documented, our understanding of the downstream molecular events underlying its mode of action remains to be elucidated. This review aims to focus on the progress in understanding the signaling mechanisms and the functional relevance of CD146, a multifaceted molecule, in cancer with particular emphasis on its role in inhibiting breast cancer progression. 相似文献
88.
There is a growing interest in understanding the complex interactions between bone marrow-derived myeloid-lineage cells and angiogenesis in tumors. Such interest has been revived recently by the observation that tumor-infiltrating myeloid cells convey proangiogenic programs that can counteract the activity of antiangiogenic drugs in mouse tumor models. Among myeloid cells, Tie2-expressing monocytes (TEMs) appear to have nonredundant function in promoting tumor angiogenesis and growth in mouse models. The identification and functional characterization of TEMs in mice and humans may provide novel molecular targets for anticancer therapy. Moreover, TEMs may be exploited to deliver antitumor drugs specifically to the tumor microenvironment. 相似文献
89.
The genomes of many species are crowded with repetitive mobile sequences. In the case of endogenous retroviruses (ERVs) there is, for various reasons, considerable confusion regarding names assigned to families/groups of ERVs as well as individual ERV loci. Human ERVs have been studied in greater detail, and naming of HERVs in the scientific literature is somewhat confusing not just to the outsider. Without guidelines, confusion for ERVs in other species will also probably increase if those ERVs are studied in greater detail. Based on previous experience, this review highlights some of the problems when naming and classifying ERVs, and provides some guidance for detecting and characterizing ERV sequences. Because of the close relationship between ERVs and exogenous retroviruses (XRVs) it is reasonable to reconcile their classification with that of XRVs. We here argue that classification should be based on a combination of similarity, structural features, (inferred) function, and previous nomenclature. Because the RepBase system is widely employed in genome annotation, RepBase designations should be considered in further taxonomic efforts. To lay a foundation for a phylogenetically based taxonomy, further analyses of ERVs in many hosts are needed. A dedicated, permanent, international consortium would best be suited to integrate and communicate our current and future knowledge on repetitive, mobile elements in general to the scientific community. 相似文献
90.
Immunogenicity of HLA-A1-restricted peptides derived from S100A4 (metastasin 1) in melanoma patients
Valeska Hofmeister-Mueller Claudia S. Vetter-Kauczok Ramona Ullrich Katharina Meder Eugene Lukanidin Eva-Bettina Broecker Per thor Straten Mads Hald Andersen David Schrama Juergen C. Becker 《Cancer immunology, immunotherapy : CII》2009,58(8):1265-1273
S100A4 (metastasin 1) belongs to the S100 family of Ca2+ binding proteins. While not present in most differentiated adult tissues, S100A4 is upregulated in the micromilieu of tumors.
It is primarily expressed by tumor-associated macrophages, fibroblasts, and tumor endothelial cells. Due to its strong induction
in tumors S100A4 is a promising target for cancer immunotherapy. By reverse immunology, using epitope prediction programs,
we identified 3 HLA-A1-restricted peptide epitopes (S100A4 A1-1, A1-2, and A1-3) which are subject to human T cell responses
as detected in peripheral blood of melanoma patients by means of IFN-γ ELISPOT and cytotoxicity assays. In addition, IFN-γ
responses to S100A4 A1-2 can not only be induced by stimulation of T cells with peptide-loaded DC but also by stimulation
with S100A4 protein-loaded DC, indicating that this epitope is indeed generated by processing of the endogenously expressed
protein. In addition, S100A4 A1-2 reactive T cells demonstrate lysis of HLA-A1+ fibroblasts in comparison to HLA-A1− fibroblasts. In summary, this HLA-A1-restricted peptide epitope is a candidate for immunotherapeutical approaches targeting
S100A4-expressing cells in the tumor stroma. 相似文献