全文获取类型
收费全文 | 2873篇 |
免费 | 150篇 |
国内免费 | 15篇 |
专业分类
耳鼻咽喉 | 17篇 |
儿科学 | 69篇 |
妇产科学 | 76篇 |
基础医学 | 426篇 |
口腔科学 | 91篇 |
临床医学 | 239篇 |
内科学 | 707篇 |
皮肤病学 | 60篇 |
神经病学 | 239篇 |
特种医学 | 42篇 |
外科学 | 286篇 |
综合类 | 12篇 |
一般理论 | 2篇 |
预防医学 | 270篇 |
眼科学 | 19篇 |
药学 | 225篇 |
中国医学 | 7篇 |
肿瘤学 | 251篇 |
出版年
2023年 | 40篇 |
2022年 | 106篇 |
2021年 | 156篇 |
2020年 | 77篇 |
2019年 | 107篇 |
2018年 | 107篇 |
2017年 | 80篇 |
2016年 | 70篇 |
2015年 | 86篇 |
2014年 | 119篇 |
2013年 | 167篇 |
2012年 | 263篇 |
2011年 | 255篇 |
2010年 | 126篇 |
2009年 | 107篇 |
2008年 | 156篇 |
2007年 | 160篇 |
2006年 | 136篇 |
2005年 | 121篇 |
2004年 | 133篇 |
2003年 | 112篇 |
2002年 | 72篇 |
2001年 | 22篇 |
2000年 | 17篇 |
1999年 | 20篇 |
1998年 | 17篇 |
1997年 | 13篇 |
1996年 | 13篇 |
1995年 | 5篇 |
1994年 | 8篇 |
1993年 | 7篇 |
1992年 | 17篇 |
1991年 | 15篇 |
1990年 | 15篇 |
1989年 | 9篇 |
1988年 | 15篇 |
1987年 | 10篇 |
1986年 | 12篇 |
1985年 | 15篇 |
1984年 | 5篇 |
1983年 | 7篇 |
1982年 | 8篇 |
1980年 | 2篇 |
1979年 | 5篇 |
1978年 | 3篇 |
1974年 | 2篇 |
1972年 | 5篇 |
1969年 | 2篇 |
1967年 | 2篇 |
1959年 | 2篇 |
排序方式: 共有3038条查询结果,搜索用时 31 毫秒
1.
Rizzo Manglio Miguel Bluthgen Mara Virginia Recondo Gonzalo Naveira Martin Perfetti Aldo Rizzi Florencia Kuzminin Alejandro Faura Victoria Cerini Matas Videla Alejandro Silva Carlos Lupinacci Lorena Minatta Nicols 《International journal of clinical oncology / Japan Society of Clinical Oncology》2021,26(6):1057-1064
International Journal of Clinical Oncology - Immune-checkpoint inhibitors (ICIs) are standard treatments for metastatic non-small cell lung cancer (NSCLC). Patients with poor performance status... 相似文献
2.
Lorena Martin-Morales Sara Manzano Maria Rodrigo-Faus Adrian Vicente-Barrueco Victor Lorca Gonzalo Núñez-Moreno Paloma Bragado Almudena Porras Trinidad Caldes Pilar Garre Alvaro Gutierrez-Uzquiza 《International journal of cancer. Journal international du cancer》2023,152(2):283-297
Matrix metalloproteinase-11 (MMP11) is an enzyme with proteolytic activity against matrix and nonmatrix proteins. Although most MMPs are secreted as inactive proenzymes and are later activated extracellularly, MMP11 is activated intracellularly by furin within the constitutive secretory pathway. It is a key factor in physiological tissue remodeling and its alteration may play an important role in the progression of epithelial malignancies and other diseases. TCGA colon and colorectal adenocarcinoma data showed that upregulation of MMP11 expression correlates with tumorigenesis and malignancy. Here, we provide evidence that a germline variant in the MMP11 gene (NM_005940: c.232C>T; p.(Pro78Ser)), identified by whole exome sequencing, can increase the tumorigenic properties of colorectal cancer (CRC) cells. P78S is located in the prodomain region, which is responsible for blocking MMP11's protease activity. This variant was detected in the proband and all the cancer-affected family members analyzed, while it was not detected in healthy relatives. In silico analyses predict that P78S could have an impact on the activation of the enzyme. Furthermore, our in vitro analyses show that the expression of P78S in HCT116 cells increases tumor cell invasion and proliferation. In summary, our results show that this variant could modify the structure of the MMP11 prodomain, producing a premature or uncontrolled activation of the enzyme that may contribute to an early CRC onset in these patients. The study of this gene in other CRC cases will provide further information about its role in CRC development, which might improve patient treatment in the future. 相似文献
3.
John Lennon Silva Cunha Amanda Almeida Leite Thamiris de Castro Abrantes Lorena Passoni Vervloet Thayn Melo de Lima Morais Gerson de Oliveira Paiva Neto Tatiana Nayara Librio Kimura Snia Maria Soares Ferreira Ricardo Luiz Cavalcanti de Albuquerque‐Júnior Aline Corrêa Abraho Mario Jos Romaach Bruno Augusto Benevenuto de Andrade Oslei Paes de Almeida Ciro Dantas Soares 《Journal of cutaneous pathology》2021,48(1):24-33
4.
5.
6.
Susi Elaine Dal''Belo Lorena Rigo Gaspar Patrícia Maria Berardo Gonçalves Maia Campos 《Skin research and technology》2006,12(4):241-246
BACKGROUND/PURPOSE: The polysaccharide-rich composition of Aloe vera extracts (Aloe barbadensis Miller), often used in cosmetic formulations, may impart moisturizing properties to the product. The aim of this study was to evaluate the effect of cosmetic formulations containing different concentrations of freeze-dried Aloe vera extract on skin hydration, after a single and a 1- and 2-week period of application, by using skin bioengineering techniques. METHODS: Stable formulations containing 5% (w/w) of a trilaureth-4 phosphate-based blend were supplemented with 0.10%, 0.25% or 0.50% (w/w) of freeze-dried Aloe vera extract and applied to the volar forearm of 20 female subjects. Skin conditions in terms of the water content of the stratum corneum and of transepidermal water loss (TEWL) (Corneometer CM 825 and Tewameter TM 210) were analysed before and after a single and 1- and 2-week period of daily application. RESULTS: After a single application, only formulations supplemented with 0.25% and 0.50% (w/w) of Aloe vera extract increased the water content of the stratum corneum, while after the 2-week period application, all formulations containing the extract (0.10%, 0.25% and 0.50%) had the same effect, in both cases as compared with the vehicle. TEWL was not modified after a single and after 1- and 2-week period of application, when compared with the vehicle. CONCLUSION: Our results show that freeze-dried Aloe vera extract is a natural effective ingredient for improving skin hydration, possibly through a humectant mechanism. Consequently, it may be used in moisturizing cosmetic formulations and also as a complement in the treatment of dry skin. 相似文献
7.
J W Babich F Keeling M A Flower L Repetto A Whitton S Fielding A Fullbrook R J Ott V R McCready 《European journal of nuclear medicine》1988,14(1):39-44
A preliminary study of the distribution of the 99mTc complex of hexamethylpropylene amine oxime (HM-PAO) in 12 patients with brain neoplasms before, during, and after radiotherapy has been performed. Untreated brain tumors were found to exhibit a range of 99mTc-HM-PAO uptake, varying from areas of markedly increased isotope activity to photopenic areas, when compared to normal brain tissue. A ratio of 99mTc-HM-PAO tumor uptake to contralateral normal tissue uptake was calculated prior to and during radiotherapy. This ratio tended to return towards unity in lesions responding to therapy. A predictable alteration in whole brain 99mTc-HM-PAO uptake during radiotherapy was not demonstrated. Unlike the radiolabeled amines, 99mTc-HM-PAO localizes in primary tumors, probably indicating that its uptake mechanism is independent of non specific amine receptors. 99mTc-HM-PAO may be useful in the study of brain tumor physiology and response to therapy. 相似文献
8.
E Campora C Naso M T Vitullo S Giudici A Camoirano L Repetto R Rosso 《Journal of chemotherapy (Florence, Italy)》1992,4(1):59-63
One hundred and thirty-seven breast cancer patients, 102 receiving adjuvant chemotherapy and 35 receiving palliative chemotherapy for metastatic disease underwent a 37-item quality-of-life questionnaire to evaluate the impact of disease and treatment on physical, psychological and social well being. Patient groups were designated as follows--Adj CT: patients undergoing the questionnaire during their adjuvant chemotherapy program; Post Adj CT: patients evaluated 3 to 8 months after termination of adjuvant chemotherapy; Mts CT: patients assessed during palliative chemotherapy for metastatic disease, and Post Mts CT: patients 3 to 8 months after termination of palliative chemotherapy. Physical and social activities were reported as unaltered or normal by 64 to 70% and 52 to 67% of patients, respectively. Psychological status was judged normal by 39 to 45% of patients. No significant differences were observed between the patients groups. In 83 to 90% of cases the patient normally took care of herself. In 62 to 87% of cases time dedicated to recreational activities was reported as unaltered. The majority of patients (84%) judged that their relationship with partner and/or family were good. Severe anxiety was reported in 19 to 28% of patients and severe depression was infrequent (3.9%). Information regarding disease and treatment given by health professionals was considered satisfactory by 80 to 100% of patients.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
9.
Claudio Babiloni Giovanni Frisoni Mircea Steriade Lorena Bresciani Giuliano Binetti Claudio Del Percio Cristina Geroldi Carlo Miniussi Flavio Nobili Guido Rodriguez Filippo Zappasodi Tania Carfagna Paolo M Rossini 《Clinical neurophysiology》2006,117(5):1113-1129
OBJECTIVE: A relationship between brain atrophy and delta rhythmicity (1.5-4 Hz) has been previously explored in Alzheimer's disease (AD) subjects [Fernandez A, Arrazola J, Maestu F, Amo C, Gil-Gregorio P, Wienbruch C, Ortiz T. Correlations of hippocampal atrophy and focal low-frequency magnetic activity in Alzheimer disease: volumetric MR imaging-magnetoencephalographic study. Am J Neuroradiol. 2003 24(3):481-487]. In this study, we tested the hypothesis that such a relationship does exist not only in AD patients but also across the continuum of subjects with mild cognitive impairment (MCI) and AD. METHODS: Resting, eyes-closed EEG data were recorded in 34 MCI and 65 AD subjects. EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10.5 Hz), alpha 2 (10.5-13 Hz), beta 1 (13-20 Hz), and beta 2 (20-30 Hz). EEG cortical sources were estimated by LORETA. Cortical EEG sources were correlated with MR-based measurements of lobar brain volume (white and gray matter). RESULTS: A negative correlation was observed between the frontal white matter and the amplitude of frontal delta sources (2-4 Hz) across MCI and AD subjects. CONCLUSIONS: These results confirmed for the first time the hypothesis that the sources of resting delta rhythms (2-4 Hz) are correlated with lobar brain volume across MCI and AD subjects. SIGNIFICANCE: The present findings support, at least at group level, the 'transition hypothesis' of brain structural and functional continuity between MCI and AD. 相似文献
10.
D'adda T Pizzi S Azzoni C Bottarelli L Crafa P Pasquali C Davoli C Corleto VD Delle Fave G Bordi C 《Human pathology》2002,33(3):322-329
Most foregut digestive endocrine neoplasms may be associated with the multiple endocrine type 1 (MEN-1) syndrome. In contrast, midgut/hindgut carcinoids never show such association. To investigate the pathogenetic involvement of the MEN-1 gene and of putative additional oncosuppressor gene(s) distal to it, a comparative analysis of loss of heterozygosity (LOH) at chromosome 11q13 to 11qter was performed in 27 foregut (pancreatic endocrine tumors [PETs]), 23 midgut (ileal and appendiceal), and 3 hindgut (rectal) endocrine tumors. LOH at the MEN-1 gene locus at 11q13 was observed in 52% of the 23 sporadic and in all 4 MEN-1-associated PETs and was found to consistently and continuously span to the most distal marker investigated at 11qter. In contrast, only occasional, discontinuous, and mostly interstitial LOH for 11q markers was observed in ileal (midgut) carcinoids, whereas no LOH was found in all appendiceal (midgut) and rectal (hindgut) carcinoids. The consistent extension of LOH from the MEN-1 region to 11qter in sporadic PETs suggests a mechanism of gene inactivation via chromosomal breakage and complete loss of chromosome 11q; furthermore, these results expand beyond the 11q13 region the search for additional oncosuppressor gene(s) potentially involved in the genesis of these neoplasms. The low frequency, limited extension, and discontinuous distribution of 11q deletions in midgut/hindgut carcinoids suggest that MEN-1 gene is not involved in the pathogenesis of these tumors. 相似文献