全文获取类型
收费全文 | 1605篇 |
免费 | 143篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 8篇 |
儿科学 | 59篇 |
妇产科学 | 41篇 |
基础医学 | 257篇 |
口腔科学 | 41篇 |
临床医学 | 280篇 |
内科学 | 321篇 |
皮肤病学 | 10篇 |
神经病学 | 117篇 |
特种医学 | 42篇 |
外科学 | 125篇 |
综合类 | 4篇 |
一般理论 | 2篇 |
预防医学 | 186篇 |
眼科学 | 14篇 |
药学 | 152篇 |
肿瘤学 | 90篇 |
出版年
2024年 | 2篇 |
2023年 | 6篇 |
2022年 | 14篇 |
2021年 | 22篇 |
2020年 | 35篇 |
2019年 | 45篇 |
2018年 | 41篇 |
2017年 | 44篇 |
2016年 | 54篇 |
2015年 | 53篇 |
2014年 | 50篇 |
2013年 | 91篇 |
2012年 | 108篇 |
2011年 | 110篇 |
2010年 | 67篇 |
2009年 | 73篇 |
2008年 | 108篇 |
2007年 | 122篇 |
2006年 | 107篇 |
2005年 | 119篇 |
2004年 | 109篇 |
2003年 | 106篇 |
2002年 | 97篇 |
2001年 | 21篇 |
2000年 | 8篇 |
1999年 | 17篇 |
1998年 | 9篇 |
1997年 | 9篇 |
1996年 | 10篇 |
1995年 | 11篇 |
1994年 | 3篇 |
1993年 | 7篇 |
1992年 | 5篇 |
1991年 | 4篇 |
1990年 | 5篇 |
1989年 | 4篇 |
1988年 | 3篇 |
1986年 | 4篇 |
1985年 | 2篇 |
1984年 | 4篇 |
1983年 | 3篇 |
1982年 | 4篇 |
1980年 | 3篇 |
1979年 | 7篇 |
1978年 | 5篇 |
1977年 | 2篇 |
1976年 | 3篇 |
1974年 | 3篇 |
1965年 | 1篇 |
1927年 | 3篇 |
排序方式: 共有1749条查询结果,搜索用时 10 毫秒
1.
2.
3.
4.
Marja Hilska Yrj? Collan Peter J Roberts Jari Ovaska Jyrki K?ssi Hannu Paajanen Matti Laato 《Acta chirurgica》2002,168(2):84-90
OBJECTIVE: To compare the ability of various methods of staging and grading to predict survival in proximal colon cancer. DESIGN: Retrospective study. SETTING: University hospital, Finland. SUBJECTS: 153 patients with primary proximal colon cancer. MAIN OUTCOME MEASURES: Staging by four classification systems, grading by two grading systems, and survival analysis based on Kaplan-Meier survival curves. RESULTS: In all staging systems the survival curves of different stages differed significantly from each other. The modified Dukes' classification was still the best predictor of survival. Grade of tumours had no significant effect on long term survival, but short term survival was affected adversely by the presence of anaplastic tissue. Tumours with no mucin had a worse prognosis than those that produced mucin. All staging methods were superior to either of the histological grading systems tested as prognosticators. Tumour depth correlated with the operator's clinical impression of radicality of operation, and also predicted survival. CONCLUSION: The clinicopathological modified Dukes' staging system was the most powerful prognosticator in proximal colonic cancer and its use in clinical practice should continue. Even a small amount of anaplastic tissue (> or = 5%) had an adverse effect on short term survival. 相似文献
5.
6.
Depression-executive dysfunction syndrome in stroke patients. 总被引:6,自引:0,他引:6
Risto Vataja Tarja Pohjasvaara Riitta M?ntyl? Raija Ylikoski Maarit Leskel? Hely Kalska Marja Hietanen Hannu Juhani Aronen Oili Salonen Markku Kaste Antero Lepp?vuori Timo Erkinjuntti 《The American journal of geriatric psychiatry》2005,13(2):99-107
OBJECTIVE: It has been suggested that executive dysfunction could be the core defect in patients with geriatric or vascular depression, and that this depression-dysexecutive syndrome (DES) might be related to frontal-subcortical circuit dysfunction. The authors tested this hypothesis in 158 poststroke patients, of whom 21 had both depression and executive dysfunction. Methods: In this cross-sectional cohort study, a neurological, psychiatric, and neuropsychological examination was carried out 3 months after ischemic stroke, and brain infarcts, white-matter changes, and brain atrophy were recorded by MRI. RESULTS: The 21 patients with DES had significantly more brain infarcts affecting their frontal-subcortical circuit structures than the 137 patients without DES, or the 41 patients with depression but without executive dysfunction. Patients with DES also had more severe depressive symptoms and worse psychosocial functioning, and they coped less well in complex activities of daily living. CONCLUSIONS: DES is a valid concept and may define a subgroup of poststroke patients with frontal-subcortical pathology and with distinct prognosis and treatment options. 相似文献
7.
Thomas Zeiler MD Antti Taivainen MD PhD Marja Rytkönen PhD Jaakko Rautiainen MSc Henry Karjalainen PhD Rauno Mäntjärvi MD PhD Leena Tuomisto MD PhD Tuomas Virtanen MD PhD 《The Journal of allergy and clinical immunology》1997,100(6):721-727
Background: Lately, renewed interest has arisen in the new forms of allergen immunotherapy because they may offer alternatives for drug treatment. Objective: The purpose of this study was to develop a well-characterized preparation of the main respiratory cow dander allergen, Bos d 2, with attenuated allergenic activity. Methods: The immunologic characteristics of Bos d 2 preparations were studied by indirect IgE ELISA, ELISA inhibition, Western blotting, histamine release, skin prick tests, and the proliferation tests of allergen-specific T-cell clones. Results: The complete recombinant Bos d 2 was observed to bind effectively, IgE of cow-allergic patients in indirect ELISA. In other experiments, the IgE-binding capacity of recombinant Bos d 2 proved to be lower compared with native Bos d 2. When the two overlapping recombinant fragments of Bos d 2 (corresponding amino acids 1-131 and 81-172, respectively) covering the whole molecule were compared with the complete recombinant Bos d 2 with several methods, only a low level of residual reactivity was observed. For example, recombinant fragments could not bind antibody at all in ELISA inhibition tests retaining, however, some reactivity in skin prick tests. In contrast, the fragments were able to stimulate vigorously Bos d 2-specific T-cell clones. Conclusion: The approach we have taken may offer a simple and reproducible way to produce hypoallergenic preparations for immunotherapy, circumventing simultaneously some of the problems of other experimental methods such as individual T-cell epitope recognition in peptide-based immunotherapy. (J Allergy Clin Immunol 1997;100:721-7.) 相似文献
8.
Vascular endothelial growth factor C is required for sprouting of the first lymphatic vessels from embryonic veins 总被引:3,自引:0,他引:3
Karkkainen MJ Haiko P Sainio K Partanen J Taipale J Petrova TV Jeltsch M Jackson DG Talikka M Rauvala H Betsholtz C Alitalo K 《Nature immunology》2004,5(1):74-80
Lymphatic vessels are essential for immune surveillance, tissue fluid homeostasis and fat absorption. Defects in lymphatic vessel formation or function cause lymphedema. Here we show that the vascular endothelial growth factor C (VEGF-C) is required for the initial steps in lymphatic development. In Vegfc-/- mice, endothelial cells commit to the lymphatic lineage but do not sprout to form lymph vessels. Sprouting was rescued by VEGF-C and VEGF-D but not by VEGF, indicating VEGF receptor 3 specificity. The lack of lymphatic vessels resulted in prenatal death due to fluid accumulation in tissues, and Vegfc+/- mice developed cutaneous lymphatic hypoplasia and lymphedema. Our results indicate that VEGF-C is the paracrine factor essential for lymphangiogenesis, and show that both Vegfc alleles are required for normal lymphatic development. 相似文献
9.
Wessels MW Catsman-Berrevoets CE Mancini GM Breuning MH Hoogeboom JJ Stroink H Frohn-Mulder I Coucke PJ Paepe AD Niermeijer MF Willems PJ 《American journal of medical genetics. Part A》2004,131(2):134-143
Arterial tortuosity syndrome (ATS) is a rare condition with autosomal recessive inheritance characterized by connective tissue abnormalities. The most specific clinical findings are cardiovascular anomalies including tortuosity, lengthening, aneurysm, and stenosis formation of major arteries. Also ventricular hypertrophy is frequently present. Other anomalies are skin hyperextensibility and cutis laxa, joint laxity or contractures of the joints, and inguinal herniae. Histology shows disruption of elastic fibers of the media. These features suggest that ATS is a connective tissue disorder. A biochemical or molecular defect has not yet been identified. We describe here nine additional ATS patients from three consanguineous Moroccan families and review a total of 35 patients with this uncommon condition. 相似文献
10.
Rohde M Daugaard M Jensen MH Helin K Nylandsted J Jäättelä M 《Genes & development》2005,19(5):570-582
Whereas the stress-inducible heat-shock protein 70 (Hsp70) has gained plenty of attention as a putative target for tumor therapy, little is known about the role of other Hsp70 proteins in cancer. Here we present the first thorough analysis of the expression and function of the cytosolic Hsp70 proteins in human cancer cells and identify Hsp70-2, a protein essential for spermatogenesis, as an important regulator of cancer cell growth. Targeted knock-down of the individual family members by RNA interference revealed that both Hsp70 and Hsp70-2 were required for cancer cell growth, whereas the survival of tumorigenic as well as nontumorigenic cells depended on Hsc70. Cancer cells depleted for Hsp70 and Hsp70-2 displayed strikingly different morphologies (detached and round vs. flat senescent-like), cell cycle distributions (G2/M vs. G1 arrest) and gene expression profiles. Only Hsp70-2 depletion induced the expression of macrophage inhibitory cytokine-1 that was identified as a target of P53 tumor-suppressor protein and a mediator of the G1 arrest and the senescent phenotype. Importantly, concomitant depletion of Hsp70 and Hsp70-2 had a synergistic antiproliferative effect on cancer cells. Thus, highly homologous Hsp70 proteins bring about nonoverlapping functions essential for cell growth and survival. 相似文献