全文获取类型
收费全文 | 360737篇 |
免费 | 32301篇 |
国内免费 | 15421篇 |
专业分类
耳鼻咽喉 | 4090篇 |
儿科学 | 7344篇 |
妇产科学 | 5251篇 |
基础医学 | 55994篇 |
口腔科学 | 8463篇 |
临床医学 | 30615篇 |
内科学 | 56922篇 |
皮肤病学 | 6944篇 |
神经病学 | 16934篇 |
特种医学 | 10436篇 |
外国民族医学 | 234篇 |
外科学 | 32782篇 |
综合类 | 57095篇 |
现状与发展 | 85篇 |
一般理论 | 12篇 |
预防医学 | 15362篇 |
眼科学 | 5390篇 |
药学 | 33541篇 |
107篇 | |
中国医学 | 11183篇 |
肿瘤学 | 49675篇 |
出版年
2024年 | 480篇 |
2023年 | 4768篇 |
2022年 | 6578篇 |
2021年 | 12896篇 |
2020年 | 11717篇 |
2019年 | 11730篇 |
2018年 | 11769篇 |
2017年 | 12252篇 |
2016年 | 12986篇 |
2015年 | 14267篇 |
2014年 | 21769篇 |
2013年 | 24111篇 |
2012年 | 20762篇 |
2011年 | 23062篇 |
2010年 | 19196篇 |
2009年 | 17873篇 |
2008年 | 18133篇 |
2007年 | 18667篇 |
2006年 | 17032篇 |
2005年 | 15369篇 |
2004年 | 13267篇 |
2003年 | 11697篇 |
2002年 | 9677篇 |
2001年 | 8682篇 |
2000年 | 7196篇 |
1999年 | 6433篇 |
1998年 | 5915篇 |
1997年 | 5411篇 |
1996年 | 4947篇 |
1995年 | 4344篇 |
1994年 | 3831篇 |
1993年 | 3194篇 |
1992年 | 2761篇 |
1991年 | 2509篇 |
1990年 | 2025篇 |
1989年 | 1837篇 |
1988年 | 1701篇 |
1987年 | 1347篇 |
1986年 | 1240篇 |
1985年 | 2202篇 |
1984年 | 2248篇 |
1983年 | 1645篇 |
1982年 | 1832篇 |
1981年 | 1604篇 |
1980年 | 1280篇 |
1979年 | 1074篇 |
1978年 | 799篇 |
1977年 | 614篇 |
1976年 | 622篇 |
1975年 | 404篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
《Transfusion and apheresis science》2022,61(1):103368
The endothelium is a single-layered structure that responds to physical and chemical signals with various factors it synthesizes. In the early days of its discovery, as the inner wall of the vessels, the endothelium was thought to be a simple barrier that lays on the surface. Over time it is discovered that endothelium maintains body homeostasis with the molecules it synthesizes, despite its simple single-layer structure. It has been accepted as an important organ that contributes to the maintenance of vascular tone, cell adhesion, inflammation, vascular permeability and coagulation. Any imbalance in these physiological and pathological events causes endothelial dysfunction. This can cause many diseases such as atherosclerosis, hypertension, diabetes, or it can occur because of these. Endothelial related disorders may also complicate hematopoietic stem cell transplantation (HSCT), which is used to treat various hematologic and neoplastic diseases. These life-threatening complications include graft-versus-host disease, hepatic veno-occlussive disease, transplant-associated thrombotic microangiopathy and diffuse alveolar hemorrhage. They share a similar pathophysiology involving endothelial cells with different clinical presentations. Therefore, current researche on the issue is putting the endothelium under the spotlight for novel markers and treatment options that should be used to monitor or treat at least some of these complications following HSCT. 相似文献
13.
《The British journal of oral & maxillofacial surgery》2022,60(7):890-895
Patients undergoing sentinel node biopsy (SLNB) for early oral squamous cell carcinoma (OSCC) who harbour occult metastases (pN+ve) may be at greater risk of mortality due to prolonged overall treatment times than those identified as pN+ve on elective neck dissection (ELND). A retrospective comparative survival analysis was therefore undertaken to test this hypothesis. Patients were identified from the South Glasgow multidisciplinary team (MDT) database. Group 1 comprised 38 patients identified as pN+ve, or who were false negative, on sentinel lymph node biopsy (SLNB). Group 2 comprised 146 patients staged pN+ve on ELND. The groups were compared with the Kaplan Meier method and Cox proportional hazards model. In addition, a matched-pair analysis was performed. A unique and specifically designed algorithm was deployed to optimise the pairings. No difference in disease-specific or overall survival was found between the groups. Patients undergoing SLNB as the initial neck staging modality in early OSCC and are identified as pN+ve do not appear to be at a survival disadvantage compared with those staged with ELND. 相似文献
14.
Collagens are the most abundant proteins in the extracellular matrix. They provide a framework to build organs and tissues and give structural support to make them resistant to mechanical load and forces. Several intra‐ and extracellular modifications are needed to make functional collagen molecules, intracellular post‐translational modifications of proline and lysine residues having key roles in this. In this article, we provide a review on the enzymes responsible for the proline and lysine modifications, that is collagen prolyl 4‐hydroxylases, 3‐hydroxylases and lysyl hydroxylases, and discuss their biological functions and involvement in diseases. 相似文献
15.
Syed M. Gilani Muhammad Khan Andrea Barbieri Manju L. Prasad 《Diagnostic Histopathology》2021,27(6):263-271
Anaplastic thyroid carcinoma (ATC) is an aggressive thyroid malignancy with high mortality rate. This malignancy arises in thyroid follicular cells either denovo or with an associated differentiated thyroid carcinoma component. Clinically, it usually presents as a rapidly enlarging mass, pain and locally compressive symptoms. Histopathologic variability and heterogeneity often pose diagnostic challenges, especially in scant and paucicellular specimens. This article describes the clinical, histopathologic and molecular features of ATC and also addresses the associated diagnostic limitations and challenges. 相似文献
16.
The adrenal cortex gives rise to a biologically heterogenous group of neoplasms, each with a distinct morphology, antigen expression and molecular profile. Adrenal cortical adenomas have excellent prognosis and are usually cured by surgical resection alone, while adrenal cortical carcinomas are very aggressive tumors with a poor prognosis regardless of therapy. These tumors are rare and often challenging for a pathologist to diagnose, as significant overlap exists between benign and malignant lesions in some cases. In this review, we attempt to summarize most important histologic and clinical features of adrenal cortical adenomas and carcinomas, clarify the use of different grading systems, the use of special stains and the differential diagnosis for practicing pathologists. Most relevant hereditary syndromes associated with adrenal cortical tumors are listed. Updates in molecular alterations in adrenal cortical neoplasms and hyperplastic diseases as well as their clinical significance and potential therapeutic implications are also discussed. 相似文献
17.
ObjectiveEach pulmonary segment is an anatomical and functional unit. However, it is fundamentally difficult to precisely distinguish every pulmonary segment using the conventional pulmonary intersegmental planes from computed tomography images. Building arteriopulmonary segments is likely to be an effective way to identify pulmonary segments.MethodsThe thoracic computed tomography images of 40 patients were collected. The anatomic structures of interest were extracted in the transverse, sagittal, and coronal planes using the semi-automated segmentation tools provided by Amira software. The intrapulmonary vessels were subsequently segmented and reconstructed. The distributions of the pulmonary arteries, veins, and bronchi were observed. In patients with pulmonary masses, the mass was also reconstructed.ResultsThe three-dimensional reconstructed images showed the branches of the pulmonary artery ramified up to their eighth order covering the entire lung as well as evident intersegmental gaps without pulmonary arteries. The segmental artery was closely accompanied by the segmental bronchi in 486 pulmonary segments (90% of total number of segments). The size and spatial location of the pulmonary mass within a pulmonary segment were also clearly visible.ConclusionsDemarcation of arteriopulmonary segments can be used to precisely distinguish every pulmonary segment and provide its detailed anatomical structure before pulmonary segmentectomy. 相似文献
18.
Hannah C. Nordhues Anjali Bhagra Natya N. Stroud Jennifer A. Vencill Carol L. Kuhle 《Mayo Clinic proceedings. Mayo Clinic》2021,96(7):1907-1920
The coronavirus disease 2019 (COVID-19) pandemic has rapidly created widespread impacts on global health and the economy. Data suggest that women are less susceptible to severe illness. However, sex-disaggregated data are incomplete, leaving room for misinterpretation, and focusing only on biologic sex underestimates the gendered impact of the pandemic on women. This narrative review summarizes what is known about gender disparities during the COVID-19 pandemic and the economic, domestic, and health burdens along with overlapping vulnerabilities related to the pandemic. In addition, this review outlines recommended strategies that advocacy groups, community leaders, and policymakers should implement to mitigate the widening gender disparities related to COVID-19. 相似文献
19.
目的 运用CT区分脾脏血管性病变与淋巴瘤。方法 回顾性分析20例经手术、穿刺病理学检查证实的脾脏病变的发病年龄、性别、脾脏指数、病变大小、数目、有无液化、钙化、强化幅度、强化方式等特征,并进行统计学分析。结果 20例脾脏病变中,11例血管性病变(6例海绵状血管瘤,3例窦岸细胞血管瘤,2例硬化性血管瘤样结节性转化),9例淋巴瘤;两组间发病年龄、病变大小、数目、有无液化、钙化等差异无统计学意义;两组间脾脏指数、动脉期强化幅度差异具有统计学意义(P<0.05)。5例海绵状血管瘤呈不均匀性强化,1例呈渐进性填充式强化,2例窦岸细胞血管瘤呈“雀斑征”,1例硬化性血管瘤样结节性转化呈“辐轮征”;9例淋巴瘤实质部分均呈均匀、轻中度强化。结论 脾脏血管性病变与淋巴瘤CT表现不同,CT有助于明确诊断。 相似文献
20.
Her-Shyong Shiah Nai-Jung Chiang Chia-Chi Lin Chia-Jui Yen Hui-Jen Tsai Shang-Yin Wu Wu-Chou Su Kwang-Yu Chang Ching-Chiung Wang Jang-Yang Chang Li-Tzong Chen 《The oncologist》2021,26(4):e567-e579
Lessons Learned
- SCB01A is a novel microtubule inhibitor with vascular disrupting activity.
- This first‐in‐human study demonstrated SCB01A safety, pharmacokinetics, and preliminary antitumor activity.
- SCB01A is safe and well tolerated in patients with advanced solid malignancies with manageable neurotoxicity.