全文获取类型
收费全文 | 6414篇 |
免费 | 351篇 |
国内免费 | 48篇 |
专业分类
耳鼻咽喉 | 32篇 |
儿科学 | 172篇 |
妇产科学 | 127篇 |
基础医学 | 921篇 |
口腔科学 | 32篇 |
临床医学 | 570篇 |
内科学 | 1635篇 |
皮肤病学 | 116篇 |
神经病学 | 879篇 |
特种医学 | 141篇 |
外科学 | 501篇 |
综合类 | 10篇 |
一般理论 | 1篇 |
预防医学 | 324篇 |
眼科学 | 66篇 |
药学 | 497篇 |
中国医学 | 14篇 |
肿瘤学 | 775篇 |
出版年
2023年 | 40篇 |
2022年 | 113篇 |
2021年 | 170篇 |
2020年 | 105篇 |
2019年 | 150篇 |
2018年 | 171篇 |
2017年 | 141篇 |
2016年 | 177篇 |
2015年 | 174篇 |
2014年 | 237篇 |
2013年 | 303篇 |
2012年 | 444篇 |
2011年 | 461篇 |
2010年 | 290篇 |
2009年 | 272篇 |
2008年 | 429篇 |
2007年 | 414篇 |
2006年 | 409篇 |
2005年 | 422篇 |
2004年 | 415篇 |
2003年 | 332篇 |
2002年 | 293篇 |
2001年 | 63篇 |
2000年 | 46篇 |
1999年 | 66篇 |
1998年 | 93篇 |
1997年 | 70篇 |
1996年 | 55篇 |
1995年 | 55篇 |
1994年 | 43篇 |
1993年 | 40篇 |
1992年 | 30篇 |
1991年 | 36篇 |
1990年 | 31篇 |
1989年 | 29篇 |
1988年 | 20篇 |
1987年 | 20篇 |
1986年 | 14篇 |
1985年 | 23篇 |
1984年 | 25篇 |
1983年 | 15篇 |
1982年 | 10篇 |
1981年 | 8篇 |
1980年 | 12篇 |
1979年 | 5篇 |
1978年 | 11篇 |
1977年 | 13篇 |
1976年 | 3篇 |
1975年 | 3篇 |
1966年 | 3篇 |
排序方式: 共有6813条查询结果,搜索用时 772 毫秒
991.
Gambacciani M Monteleone P Vitale C Silvestri A Fini M Genazzani AR Rosano GM 《Maturitas》2002,43(2):117-123
OBJECTIVES: The purpose of this study was to evaluate endothelium-dependent flow-mediated dilation (FMD) in the brachial artery and the plasma levels of endothelin-1 in postmenopausal women at risk for coronary artery disease before and after treatment with both estradiol and estradiol plus dydrogesterone. METHODS: Sixteen postmenopausal women (PMW) (mean age 58+/-9 years) with more than two risk factors for coronary artery disease, were randomized to receive either oral estradiol (2 mg) for 28 days or oral estradiol (2 mg) for 14 days and oral estradiol (2 mg) and dydrogesterone (10 mg) for 14 days, in a double-blind, placebo-controlled, single cross-over study. Patients were crossed-over the complementary treatment 7 days after completing the first treatment. The study of forearm blood flow and the measurement of plasma endothelin-1 levels was carried out before and after each treatment. RESULTS: Estradiol significantly increased FMD as compared to baseline; the addition of dydrogesterone did not affect the effect of estradiol on FMD. Similarly reactive hyperemic flow increased after estradiol alone or in association with dydrogesterone compared to baseline. Plasma levels of endothelin-1 were significantly reduced by estradiol both when administered alone or in association with dydrogesterone. CONCLUSIONS: Hormone replacement therapy with estradiol and dydrogesterone improves endothelial function and reduces plasma levels of endothelin-1 in PMW at risk for coronary artery disease. 相似文献
992.
Luca Mascaretti Laura Baggi Mariarosa Riva Patrizia Proserpio Maria Dassi Filippo Varallo Gianalfredo Sciorelli Cinzia Quarti 《Transfusion and apheresis science》2002,26(3):167-174
Lymphocyte subsets were determined in 20 packed red blood cell units (PRC) before and after filtration (FPRC) with the Pall Leukotrap RC inline filter system; 10 units were prepared by low spin and platelet rich plasma (PRP) removal (Group A) and 10 with high spin, plasma and buffy-coat (BC) removal (Group B). Flow cytometry was employed for white blood cell (WBC) enumeration and phenotype analysis. Median WBCs in prefiltered units was 2.08 x 10(9) (Group A) vs. 0.8 x 10(9) (Group B) (p < 0.0001). Five Group A and three Group B filtered units had WBC counts above the limit of detection (LD), median values being 25.59 and 3.08 x 10(3), respectively. Whereas CD3+, CD3+CD4+ and CD3+CD8+ lymphocyte subsets were assessable in 20-40% of Group A units, inline filtration of Group B units lowered lymphocytes below the LD of the present study. Post-filtration CD19+ lymphocytes were below the LD in all the 20 units. 相似文献
993.
Patrizia Paolicelli Felice Cerreto Stefania Cesa Michelle Feeney Federica Corrente Carlotta Marianecci 《Journal of microencapsulation》2013,30(4):355-364
A system composed by solid lipid nanoparticles (SLN) entrapped into a chemical hydrogel of dextran was recently proposed for the controlled release of lipophilic drugs in oral formulations. This study reports now an extension of such study focused on the investigation of how the nature and the amount of the formulation components are able to modify the properties of the system. In particular the concentration of the two surfactants used for the nanosuspension stabilization, the nature of the lipid phase used for the nanoparticles preparation, as well as the concentration and the derivatization degree of the polymer employed for the gel preparation were investigated. The effects of these variables on the physicochemical properties of the nanoparticles and/or on the release profiles of the model drug (S)-(+)-2-(4-isobutylphenyl)-propionic acid (ibuprofen) were reported and discussed. Rheological experiments on samples of SLN, dextran hydrogel, and SLN-dextran hydrogel were also performed. 相似文献
994.
Luigi Stella Maria Redenta Vitelli Enza Palazzo Patrizia Oliva Vito De Novellis Annalisa Capuano 《Journal of psychoactive drugs》2013,45(4):507-512
Abstract This article describes three cases o f Datura stramonium intake o n two nonconsecutive days. In the first case, the patient took a small amount of D. stramonium seeds without showing any symptoms of intoxication. The other two patients had taken a considerable amount of seeds and reported a sudden surge in strength and energy, with some aggressive compulsion towards their peers. They showed delirium as well as confusion and disorientation. The absence of any specific legislation makes D. stramonium a tempting alternative to other psychoactive substances. Thus, it is extremely important to be able to recognize its symptoms so as to be able to diagnose any signs of intoxication properly. 相似文献
995.
Rosario Pignatello Davide Amico Santina Chiechio Concetta Spadaro Giovanni Puglisi Paolo Giunchedi 《Drug delivery》2013,20(1):35-45
Two different techniques, the quasi-emulsion solvent diffusion method and spray drying that provide polar and nonpolar preparation environments, were used to prepare microspheres from Eudragit RS100® (RS) (acrylic/methacrylic copolymer) incorporating the nonsteroidal anti-inflammatory drug diflunisal. The effects of pH on the preparation medium and drug/polymer ratio on production yield and drug incorporation, as well as on the in vitro drug release at pH 1.2 and 6.8 from tabletted microparticles, were evaluated. The drug-polymer interactions and the effect of diflunisal incorporation in the polymer matrix on drug crystallinity have been evaluated by using differential scanning calorimetry, IR and ultraviolet spectroscopy, x-ray diffraction, and microscopy analysis. A preliminary biological assay confirmed that diflunisal maintains its analgesic activity after intraperitoneal administration to rats. 相似文献
996.
Ilaria Plantamura Patrizia Casalini Erica Dugnani Marianna Sasso Elvira D'Ippolito Monica Tortoreto Matilde Cacciatore Carla Guarnotta Cristina Ghirelli Isabella Barajon Francesca Bianchi Tiziana Triulzi Roberto Agresti Andrea Balsari Manuela Campiglio Claudio Tripodo Marilena V. Iorio Elda Tagliabue 《Molecular oncology》2014,8(5):968-981
Triple negative breast cancer (TNBC) is a very aggressive subgroup of breast carcinoma, still lacking specific markers for an effective targeted therapy and with a poorer prognosis compared to other breast cancer subtypes.In this study we investigated the possibility that TNBC cells contribute to the establishment of tumor vascular network by the process known as vasculogenic mimicry, through endothelial cell differentiation.Vascular‐like functional properties of breast cancer cell lines were investigated in vitro by tube formation assay and in vivo by confocal microscopy, immunofluorescence or immunohistochemistry on frozen tumor sections. TNBCs express endothelial markers and acquire the ability to form vascular‐like channels in vitro and in vivo, both in xenograft models and in human specimens, generating blood lacunae surrounded by tumor cells. Notably this feature is significantly associated with reduced disease free survival. The impairment of the main pathways involved in vessel formation, by treatment with inhibitors (i.e. Sunitinib and Bevacizumab) or by siRNA‐mediating silencing, allowed the identification of PDGFRβ and FGFR2 as relevant players in this phenomenon. Inhibition of these tyrosine kinase receptors negatively affects vascular lacunae formation and significantly inhibits TNBC growth in vivo.In summary, we demonstrated that TNBCs have the ability to form vascular‐like channels in vitro and to generate blood lacunae lined by tumor cells in vivo. Moreover, this feature is associated with poor outcome, probably contributing to the aggressiveness of this breast cancer subgroup. Finally, PDGFRβ and FGFR2‐mediated pathways, identified as relevant in mediating this characteristic, potentially represent valid targets for a specific therapy of this breast cancer subgroup. 相似文献
997.
Elena Ardini Roberta Bosotti Andrea Lombardi Borgia Cristina De Ponti Alessio Somaschini Rosaria Cammarota Nadia Amboldi Laura Raddrizzani Andrea Milani Paola Magnaghi Dario Ballinari Daniele Casero Fabio Gasparri Patrizia Banfi Nilla Avanzi Maria B. Saccardo Rachele Alzani Tiziano Bandiera Eduard Felder Daniele Donati Enrico Pesenti Andrea Sartore-Bianchi Marcello Gambacorta Marco A. Pierotti Salvatore Siena Silvio Veronese Arturo Galvani Antonella Isacchi 《Molecular oncology》2014,8(8):1495-1507
998.
Patrizia Vici Marcella Mottolese Laura Pizzuti Maddalena Barba Francesca Sperati Irene Terrenato Anna Di Benedetto Clara Natoli Teresa Gamucci Domenico Angelucci Maria Teresa Ramieri Luigi Di Lauro Domenico Sergi Monica Bartucci Rosanna Dattilo Alfredo Pagliuca Ruggero De Maria Marcello Maugeri-Saccà 《Oncotarget》2014,5(20):9619-9625
Activation of the Hippo transducer TAZ is emerging as a novel oncogenic route in breast cancer and it has been associated with breast cancer stem cells. Additionally, TAZ expression has been linked with HER-2 positivity. We investigated the association between TAZ expression and pathological complete response in HER2-positive breast cancer patients treated with trastuzumab-based neoadjuvant therapy. TAZ was assessed in diagnostic core biopsies by immunohistochemistry. To categorize samples with low TAZ and samples with high TAZ we generated a score by combining staining intensity and cellular localization. The pathological complete response rate was 78.6% in patients with low TAZ tumors and 57.6% in patients with high TAZ tumors (p=0.082). In HER2-enriched tumors there was no significant association between TAZ and pathological complete response, whereas in the luminal B subtype the pathological complete response rate was 82.4% in tumors with low TAZ and 44.4% in tumors with high TAZ (p=0.035). This association remained statistically significant when restricting our analysis to triple-positive tumors with expression of both estrogen receptor and progesterone receptor ≥ 50% (p=0.035). Results from this exploratory study suggest that the TAZ score efficiently predicts pathological complete response in Luminal B, HER2-positive breast cancer patients who received neoadjuvant chemotherapy and trastuzumab. 相似文献
999.
Katia Bifulco Giuseppina Votta Vincenzo Ingangi Gioconda Di Carluccio Domenica Rea Simona Losito Nunzia Montuori Pia Ragno Maria Patrizia Stoppelli Claudio Arra Maria Vincenza Carriero 《Oncotarget》2014,5(12):4154-4169
The clinical relevance of the urokinase receptor (uPAR) as a prognostic marker in ovarian cancer is well documented. We have shown that the uPAR sequence corresponding to 84-95 residues, linking D1 and D2 domains (uPAR84-95), drives cell migration and angiogenesis in a protease-independent manner. This study is aimed at defining the contribution of uPAR84-95 sequence to invasion of ovarian cancer cells. Now, we provide evidence that the ability of uPAR-expressing ovarian cancer cells to cross extra-cellular matrix and mesothelial monolayers is prevented by specific inhibitors of PAR84-95 sequence. To specifically investigate uPAR84-95 function, uPAR-negative CHO-K1 cells were stably transfected with cDNAs coding for uPAR D2 and D3 regions and exposing (uPARD2D3) or lacking (uPARΔD2D3) the 84–95 sequence. CHO-K1/D2D3 cells were able to cross matrigel, mesothelial and endothelial monolayers more efficiently than CHO-K1/ΔD2D3 cells, which behave as CHO-K1 control cells. When orthotopically implanted in nude mice, tumor nodules generated by CHO-K1/D2D3 cells spreading to peritoneal cavity were more numerous as compared to CHO-K1/ΔD2D3 cells. Ovarian tumor size and intra-tumoral microvessel density were significantly reduced in the absence of uPAR84-95. Our results indicate that cell associated uPAR promotes growth and abdominal dissemination of ovarian cancer cells mainly through its uPAR84-95 sequence. 相似文献
1000.
Patrizia Ferroni Fiorella Guadagni Anastasia Laudisi Matteo Vergati Silvia Riondino Antonio Russo Giovanni Davì Mario Roselli 《The oncologist》2014,19(5):562-567