全文获取类型
收费全文 | 2482篇 |
免费 | 234篇 |
国内免费 | 74篇 |
专业分类
耳鼻咽喉 | 33篇 |
儿科学 | 64篇 |
妇产科学 | 2篇 |
基础医学 | 372篇 |
口腔科学 | 7篇 |
临床医学 | 105篇 |
内科学 | 144篇 |
皮肤病学 | 91篇 |
神经病学 | 479篇 |
特种医学 | 101篇 |
外国民族医学 | 2篇 |
外科学 | 335篇 |
综合类 | 272篇 |
预防医学 | 18篇 |
眼科学 | 61篇 |
药学 | 68篇 |
1篇 | |
中国医学 | 4篇 |
肿瘤学 | 631篇 |
出版年
2024年 | 2篇 |
2023年 | 38篇 |
2022年 | 75篇 |
2021年 | 107篇 |
2020年 | 74篇 |
2019年 | 81篇 |
2018年 | 75篇 |
2017年 | 76篇 |
2016年 | 89篇 |
2015年 | 134篇 |
2014年 | 121篇 |
2013年 | 179篇 |
2012年 | 126篇 |
2011年 | 136篇 |
2010年 | 102篇 |
2009年 | 105篇 |
2008年 | 123篇 |
2007年 | 109篇 |
2006年 | 92篇 |
2005年 | 111篇 |
2004年 | 78篇 |
2003年 | 74篇 |
2002年 | 80篇 |
2001年 | 54篇 |
2000年 | 68篇 |
1999年 | 45篇 |
1998年 | 63篇 |
1997年 | 36篇 |
1996年 | 38篇 |
1995年 | 42篇 |
1994年 | 35篇 |
1993年 | 30篇 |
1992年 | 30篇 |
1991年 | 25篇 |
1990年 | 19篇 |
1989年 | 10篇 |
1988年 | 15篇 |
1987年 | 10篇 |
1986年 | 11篇 |
1985年 | 15篇 |
1984年 | 10篇 |
1983年 | 7篇 |
1982年 | 13篇 |
1981年 | 10篇 |
1980年 | 4篇 |
1979年 | 5篇 |
1978年 | 3篇 |
1977年 | 3篇 |
1976年 | 2篇 |
排序方式: 共有2790条查询结果,搜索用时 15 毫秒
21.
对经手术病理证实,CT资料完善的114例脑膜瘤进行回顾性分析,研究脑膜瘤的部位、大小、组织学类型及其它的生物学特性与瘤周水肿的相关性。通过CT确定瘤周水肿的有无及程度,对各种参数采用χ2、秩和等统计学检验方法进行分析。脑膜瘤瘤周水肿的发生与肿瘤的病理组织学类型有关,而与肿瘤的大小、钙化、病人的年龄和性别无关,上皮型、血管型及恶性脑膜瘤较其它组织学类型更易发生瘤周水肿。颅内压增高与瘤周水肿的发生密切相关,矢状窦旁、大脑凸面、镰旁、蝶骨嵴、前颅窝及嗅沟部脑膜瘤较幕下及其它部位脑膜瘤易发生瘤周脑水肿,但上述各部位间瘤周水肿的发生率比较无统计学差异。性别、年龄、病程与瘤周水肿的发生无关 相似文献
22.
cDNA arrays are a powerful tool for the identification of differentially expressed genes in malignant tumors. We used this technique to study the gene expression profiles of anaplastic large cell lymphoma (ALCL) and Hodgkin's disease (HD). Gene expression of 11 lymphoma cell lines was analyzed covering 1176 cDNA sequences. Comparing these data to the expression profiles of B- and T-lymphocytes, we identified 27 genes that were deregulated in all cell lines or in a particular entity. For the establishment of gene expression profiles the 27 genes were assigned to four groups composed of genes deregulated in (i) all lymphoma cell lines, (ii) ALCL and HD, (iii) only HD, and (iv) ALCL exclusively. Our results indicate that ALCL and HD share the differential expression of at least five genes. In addition, both entities are characterized by the differentially deregulated expression of four genes in HD and seven genes in ALCL. Because the expression profiling was performed on cell lines, further studies are needed to clarify the biological significance of the differentially expressed genes. 相似文献
23.
目的研究凋亡相关蛋白mdm2、bcl-2和AR(雄激素受体)之间的关系,为脑膜瘤的性激素对抗治疗提供一些新信息。方法从华西医院病理科获得04年1月-07年12月病理诊断明确的脑膜瘤共394例,计算机随机抽样60例,其中良性脑膜瘤(WH0I)41例,用LsAB法做免疫组化染色,检测mdm2、bcl-2、AR的表达。结果在良性脑膜瘤中mdm2、bcl-2、AR的表达率分别为67%、62%、33%,三者之间没有相关关系。结论(1)是否能够作为抗性激素治疗疗效的筛选和/或预测指标,bcl-2比mdm2更有潜在价值。(2)AR在脑膜瘤中的促进生长作用的相对独立性,提示AR可以作为脑膜瘤对抗激素治疗的新靶点进一步研究。 相似文献
24.
Allelic losses at 1p, 9q, 10q, 14q, and 22q in the progression of aggressive meningiomas and undifferentiated meningeal sarcomas 总被引:9,自引:0,他引:9
Lamszus K Kluwe L Matschke J Meissner H Laas R Westphal M 《Cancer Genetics and Cytogenetics》1999,110(2):310-110
Meningiomas are usually benign tumors; however, they can recur after surgical resection and occasionally show histological progression to a higher malignancy grade. Five such rare cases of aggressively recurring meningiomas were present in our departmental cohort of 923 primary meningeal neoplasms operated over a 17-year period. Four other aggressively recurring meningeal tumors with a very similar clinical and histomorphological appearance (three undifferentiated meningeal sarcomas, one hemangiopericytoma) were also included in this study. We investigated whether disease progression can be traced by genetic alterations and whether a pattern of genetic alterations is specific for meningiomas. A total of 40 specimens from primary tumors and multiple recurrences of the nine patients were analyzed with 26 polymorphic allelic markers for deletions on 1p, 1q, 9q, 10q, 14q, and 22q. Loss of heterozygosity (LOH) at 22q was observed in all meningiomas cases at the earliest time point analyzed. Allelic loss at 1p was seen in the original tumor in two cases and upon meningioma recurrence in two others. Deletion on 10q occurred during tumor progression in two cases, and on 9q and 14q in one case. While allelic loss at 22q appears to be an early event in aggressive meningioma disease, there is a clear correlation of further deletions on chromosome arms 1p, 9q, 10q, and 14q with histopathological and clinical progression, as shown in these intraindividual trackings. None of these genetic findings were present in the non-meningiomatous meningeal tumors, indicating that meningothelial cells have their own lineage-specific genetic pathways towards clinical malignancy. 相似文献
25.
间变性大细胞淋巴瘤形态学及免疫表型观察 总被引:1,自引:1,他引:1
目的:探讨间变性大细胞淋巴瘤(ALCL)的形态学和免疫表型特征。方法:对6例ALCL和2例弥温性大B细胞淋巴瘤(DLBCL)进行形态学和免疫组织化学染色(ABC法)观察。结果:6例ALCL中,普通型2例、淋巴组织细胞型2例、ALK-变型2例,均可见单型性或多形性的标志性大细胞。普通型和ALK-变型大细胞沿淋巴窦内生长,而淋巴组织细胞型大细胞则呈散在分布;2例DLBCL形态上颇似ALCL;6例ALCL均为T细胞,CD30+,儿童患者共同表达ALK+和EMA+,年长者则ALK-和EMA-。2例DLBCL均为B细胞,ALK+、CD30-和EMA-。结论:不论何型ALCL,均可见CD30+的标志性大细胞,淋巴窦内生长多见于普通型和ALK-变型。ALCK均为T细胞,儿童常有ALK和EMA共同表达,年长者则ALK和EMA-。DLBCL的免疫表型不同于ALCL。 相似文献
26.
A. Le Tourneau J. Audouin J. Diebold 《Virchows Archiv : an international journal of pathology》1988,413(3):215-222
Summary The ultrastructural morphology of 4 cases of large anaplastic cell malignant lymphoma (Ana ML) is reported. Three cases were primary Ana ML and one pleomorphic large T cell lymphoma with some Ki-1 positive cells. All were confirmed by immunohistochemistry on frozen and paraffin sections. The Ki-1 and EMA positive tumour cells had an abundant cytoplasm, with no differentiation and large pale nuclei with multiple compact or dispersed nucleoli. The morphology is that of an activated cell engaged in protein synthesis and/or in the mitotic cycle. These tumour cells resemble to the Hodgkin's and monolobated Reed-Sternberg cells described in Hodgkin's disease. 相似文献
27.
Geriatric cancer patients present special challenges for clinicians. Few large series have been published in the last 20 years on the types of neoplasms that involve the central nervous system (CNS) in older individuals. To review types of neoplasms involving the central CNS that are currently being encountered by pathologists and neurosurgeons, we identified from our databases for the years 1992-2002, inclusive, patients 75 years or older who had symptomatic lesions requiring neurosurgical interventions. Retrospective characterization of tumors by immunohistochemistry, in situ hybridization, and fluorescence in situ hybridization was performed whenever possible and relevant to tumor type. Neurosurgical procedures (n=125) on 119 patients were identified; 90 patients were diagnosed as having neoplasms, with clot evacuation or infections being the most frequent non-neoplastic conditions necessitating surgery. Tumor types included glioblastomas (36 patients), meningiomas (16), pituitary adenomas (12), lymphomas or other hematological malignancies (8), anaplastic gliomas (5), metastases (6), head and neck malignancies with direct intracranial extension (3), and other miscellaneous tumor types (4). Compared with older literature series, we encountered a larger number of elderly patients with CNS lymphomas and fewer who came to surgery for CNS metastatic disease. In the "older old", glioblastomas are the most frequent symptomatic tumors necessitating surgical intervention. Glioblastomas in this aged cohort display the signature features of the small cell phenotype (62%), high cell cycle labeling indices (mean MIB-1-labeling index=25.1%), and either amplification of epidermal growth factor receptor or gain of chromosome 7 by fluorescence in situ hybridization (93% of assessable cases). 相似文献
28.
目的:研究脊索样脑膜瘤的临床与病理特征,以提高其早期诊断率。方法:运用组织病理学及免疫组化标记(S-P法)对3例脊索样脑膜瘤进行临床病理学和组化(PAS)、免疫组化(EMA、Vim、S-100、CK)及电镜观察。结果:组织学瘤细胞胞浆内外均见粘液,在粘液基质背景中有成簇或成行的类液滴样细胞,瘤组织中有典型的脑膜上皮漩涡结构,组化及免疫组化示PAS(+)、EMA(+)、Vim(+)、S-100(+) 相似文献
29.
Psammomatoid (juvenile) ossifying fibroma of the orbit 总被引:2,自引:0,他引:2
30.
目的;探讨不同部位鞍隔脑膜瘤(DSM)的分型以及手术方法的选择与治疗结果的关系。方法:CT扫描提示为垂体瘤和鞍结节脑膜瘤并向后发展者,用MRI复查筛选共发现DSM20例,其中9例为A型(居鞍隔上垂体柄前),5例B型(居鞍隔上垂体柄后),2例为C型(居鞍隔下蝶鞍内),4例为混合型(累及鞍隔上下和垂体柄前后)。结果:20例均行手术治疗,17例全切除,3例大部切除,无手术死亡和严重功能障碍。结论:MRI是诊断DSM的最好方法,有助于鉴别诊断、分型和手术方法的选择。鞍隔脑膜瘤的手术较鞍结节脑膜瘤的手术更为困难。 相似文献