全文获取类型
收费全文 | 2760篇 |
免费 | 177篇 |
国内免费 | 33篇 |
专业分类
耳鼻咽喉 | 28篇 |
儿科学 | 66篇 |
妇产科学 | 65篇 |
基础医学 | 403篇 |
口腔科学 | 20篇 |
临床医学 | 195篇 |
内科学 | 735篇 |
皮肤病学 | 73篇 |
神经病学 | 344篇 |
特种医学 | 93篇 |
外科学 | 266篇 |
综合类 | 6篇 |
预防医学 | 127篇 |
眼科学 | 14篇 |
药学 | 234篇 |
中国医学 | 4篇 |
肿瘤学 | 297篇 |
出版年
2024年 | 7篇 |
2023年 | 33篇 |
2022年 | 80篇 |
2021年 | 131篇 |
2020年 | 92篇 |
2019年 | 87篇 |
2018年 | 119篇 |
2017年 | 74篇 |
2016年 | 111篇 |
2015年 | 107篇 |
2014年 | 155篇 |
2013年 | 170篇 |
2012年 | 219篇 |
2011年 | 228篇 |
2010年 | 132篇 |
2009年 | 132篇 |
2008年 | 179篇 |
2007年 | 196篇 |
2006年 | 180篇 |
2005年 | 118篇 |
2004年 | 120篇 |
2003年 | 89篇 |
2002年 | 80篇 |
2001年 | 20篇 |
2000年 | 15篇 |
1999年 | 15篇 |
1998年 | 7篇 |
1997年 | 9篇 |
1995年 | 4篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1991年 | 5篇 |
1990年 | 7篇 |
1989年 | 6篇 |
1988年 | 4篇 |
1987年 | 6篇 |
1985年 | 4篇 |
1984年 | 4篇 |
1983年 | 4篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 3篇 |
1977年 | 2篇 |
1973年 | 2篇 |
1972年 | 2篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有2970条查询结果,搜索用时 62 毫秒
81.
Luisa Marracino Angela Punzo Paolo Severi Rosane Nganwouo Tchoutang Celia Vargas-De-la-Cruz Francesca Fortini Francesco Vieceli Dalla Sega Alessia Silla Emanuele Porru Patrizia Simoni Valentina Rosta Alessandro Trentini Achille Wilfred Ouambo Talla Silvana Hrelia Carlo Cervellati Paola Rizzo Cristiana Caliceti 《Nutrients》2022,14(8)
Accumulating evidence suggests that high consumption of natural antioxidants promotes health by reducing oxidative stress and, thus, the risk of developing cardiovascular diseases. Similarly, fermentation of natural compounds with lactic acid bacteria (LAB), such as Lactiplantibacillus plantarum, enhances their beneficial properties as regulators of the immune, digestive, and cardiovascular system. We investigated the effects of fermentation with Lactiplantibacillus plantarum on the antioxidant and immunomodulatory effects of Pushgay berries (Vaccinium floribundum, Ericaceae family) in human umbilical vein endothelial cells (HUVECs) and macrophage cell line RAW264.7. Polyphenol content was assayed by Folin–Ciocalteu and HPLC-MS/MS analysis. The effects of berries solutions on cell viability or proliferation were assessed by WST8 (2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium, monosodium salt and Lactate dehydrogenase (LDH) release, Trypan blue exclusion test, and Alamar blue assay. Antioxidant activity was evaluated by a cell-based chemiluminescent probe for the detection of intracellular H2O2 production in HUVECs. Heme oxygenase-1 (HO-1) expression levels were investigated by RT-qPCR. Glutathione reductase (GR), glutathione peroxidase (Gpx), superoxide dismutase (SOD), and catalase (CAT) activities, as markers of intracellular antioxidant defense, were evaluated by spectrophotometric analysis. The immunomodulatory activity was examined in RAW 264.7 by quantification of inducible nitric oxide synthase (iNOS) and Tumor Necrosis Factor—alpha (TNFα) by RT-qPCR. Data showed that fermentation of Pushgay berries (i) enhances the content of quercetin aglycone, and (ii) increases their intracellular antioxidant activity, as indicated by the reduction in H2O2-induced cell death and the decrease in H2O2-induced HO-1 gene expression in HUVECs treated for 24 h with fermented berries solution (10 µg/mL). Moreover, treatment with Pushgay berries for 72 h (10 µg/mL) promotes cells growth in RAW 264.7, and only fermented Pushgay berries increase the expression of iNOS in the same cell line. Taken together, our results show that LAB fermentation of Pushgay berries enhances their antioxidant and immunomodulatory properties. 相似文献
82.
83.
Non‐invasive measurement of right atrial pressure by near‐infrared spectroscopy: preliminary experience. A report from the SICA‐HF study 下载免费PDF全文
84.
85.
Lea Regolo Licia Galli Gianfranco Petrolo Elisabetta Scoccia Alessia De Simone Susanna Fissi Alberto Zambelli Angela Amato Vittorio Zanini 《Breast (Edinburgh, Scotland)》2013,22(1):96-97
Lipofilling is becoming part of the breast reshaping after quadrantectomy or mastectomy in breast cancer patients, but there are open questions of its safety. 相似文献
86.
Rucci N Ricevuto E Ficorella C Longo M Perez M Di Giacinto C Funari A Teti A Migliaccio S 《BONE》2004,34(4):697-709
Mouse bone marrow cells cultured with human breast cancer MCF-7 cell-conditioned media showed osteoclastogenesis with an increment of bone resorption, although conditioned media from an adriamycin-selected MCF-7 clone (MCF-7ADR) had no effect. Consistently, MCF-7 cells induced 5-fold more in vivo experimental osteolytic bone metastases, with no soft tissue lesions, compared to MCF-7ADR cells. Paracrine factors stimulating (interleukin (IL)-6, IL-1beta, tumor necrosis factor-alpha (TNF-alpha)) or inhibiting (IL-12, IL-18, granulocyte macrophage-colony stimulating factor (GM-CSF)) osteoclastogenesis were significantly increased in MCF-7ADR relative to MCF-7 cells, suggesting that the inhibitory cytokines could selectively overwhelm the effects of the stimulatory ones. Treatment of osteoblast primary cultures with MCF-7-conditioned medium induced a selective upregulation of IL-6 expression, suggesting an indirect stimulation of osteoclastogenesis via the osteoblasts. MCF-7 and MCF-7ADR showed no difference in proliferation rate. However, a higher ability to migrate and invade gelatin and matrigel was observed in MCF-7ADR. Enhanced invasiveness might result from increased metalloproteinase (MMP) activity and cytoskeleton rearrangement. MCF-7ADR cells expressed higher levels of c-Src, focal adhesion kinase (FAK), and protein tyrosine kinase 2 (PYK2) involved in cell adhesion and motility. MCF-7 and MCF-7ADR expressed high and faint levels of functional estrogen receptor alpha (ERalpha), respectively. MCF-7ADR also showed significantly higher levels of the protein kinase C (PKC) alpha and beta2 and a selective activation of PKC compared to MCF-7, where the most abundant isoforms were beta1 and delta. Heat shock protein 27 (Hsp27) was more abundant in MCF-7 cells, but failed to translocate to the nucleus in response to heat shock. In conclusion, we have demonstrated that despite the fact that MCF-7ADR cells showed a more invasive phenotype relative to MCF-7, they have low potential to induce osteolytic bone lesions and stimulate osteoclastogenesis and osteoclast activity. Therefore, we believe that reduced aggressiveness of breast carcinomas could correlate with a greater osteolytic activity featuring their bone metastases. 相似文献
87.
Decreased intracellular degradation and increased secretion of apo B-100 in Hep G2 cells after inhibition of cholesteryl ester synthesis 总被引:1,自引:0,他引:1
Chiara Ooyen Alessia Zecca Tiziano Zanelli Alberico L. Catapano 《Atherosclerosis》1997,130(1-2):143-152
Control of apolipoprotein B (apo B) secretion in hepatocytes occurs partly at the post-translational level. The key step in this process appears to be intracellular degradation of newly synthesized apo B. The aim of this paper was to investigate the mechanisms that regulate apo B secretion by Hep G2 cells, in response to the inhibition of Acyl-CoA Acyltransferase (ACAT) by the compound Sandoz 58035 (S-58035). S-58035 (20 μM) reduced cholesteryl ester synthesis from [14C]oleate by 95%, and increased significantly, in a dose-dependent manner, (2–100 μM) apo B secretion, either in control conditions (from 78±4.3 to 126±6.1 ng apo B-100/mg cell protein/4 h) or upon stimulation of apo B secretion by oleate (from 134±4.23 to 177±4.3 ng apo B/mg cell protein/4 h). This increased secretion of newly synthesized apo B-100 was confirmed by pulse experiments and by gradient ultracentrifugation of the media. Moreover pulse-chase experiments showed that the addition of S-58035 reduced intracellular degradation of apo B-100, both in control conditions and in the presence of oleate. S-58035 (20 μM) did not affect total cellular cholesterol content, but free cholesterol increased with a concomitant decrease of cholesteryl ester (−20%). S-58035 increased cellular triglyceride mass, which was observed in basal conditions (from 12.8±1.09 to 22.7±2.7 μg TG/mg cellular protein) and also in presence of oleate (from 48±0.53 to 59±6.3 μg TG/mg cellular protein). This effect is due to a stimulation of triglyceride synthesis, as determined by incorporation of [3H]glycerol into cellular triglycerides. From these data we conclude that, under our experimental conditions, triglyceride synthesis and/or availability is likely to control intracellular degradation of apo B. 相似文献
88.
Fabio Bioletto Chiara DEusebio Fabio Dario Merlo Umberto Aimasso Marta Ossola Marianna Pellegrini Valentina Ponzo Alessia Chiarotto Antonella De Francesco Ezio Ghigo Simona Bo 《Nutrients》2022,14(4)
Teduglutide has been described as an effective treatment for parenteral support (PS) reduction in patients with short bowel syndrome (SBS). However, a quantitative summary of the available evidence is still lacking. PubMed/Medline, EMBASE, Cochrane library, OVID, and CINAHL databases were systematically searched up to July 2021 for studies reporting the rate of response (defined as a ≥20% reduction in PS) to teduglutide among PS-dependent adult patients. The rate of weaning (defined as the achievement of PS independence) was also evaluated as a secondary end-point. Ten studies were finally considered in the meta-analysis. Pooled data show a response rate of 64% at 6 months, 77% at 1 year and, 82% at ≥2 years; on the other hand, the weaning rate could be estimated as 11% at 6 months, 17% at 1 year, and 21% at ≥2 years. The presence of colon in continuity reduced the response rate (−17%, 95%CI: (−31%, −3%)), but was associated with a higher weaning rate (+16%, 95%CI: (+6%, +25%)). SBS etiology, on the contrary, was not found to be a significant predictor of these outcomes, although a nonsignificant trend towards both higher response rates (+9%, 95%CI: (−8%, +27%)) and higher weaning rates (+7%, 95%CI: (−14%, +28%)) could be observed in patients with Crohn’s disease. This was the first meta-analysis that specifically assessed the efficacy of teduglutide in adult patients with SBS. Our results provide pooled estimates of response and weaning rates over time and identify intestinal anatomy as a significant predictor of these outcomes. 相似文献
89.
Alessia Cruciata Lorenzo Volpicelli Silvia Di Bari Giancarlo Iaiani Bruno Cirillo Francesco Pugliese Daniela Pellegrino Gioacchino Galardo Gloria Taliani 《Viruses》2022,14(3)
This monocentric, retrospective, two-stage observational study aimed to recognize the risk factors for a poor outcome in patients hospitalized with SARS-CoV-2 infection, and to develop and validate a risk score that identifies subjects at risk of worsening, death, or both. The data of patients with SARS-CoV-2 infection during the first wave of the pandemic were collected and analyzed as a derivation cohort. Variables with predictive properties were used to construct a prognostic score, which was tried out on a validation cohort enrolled during the second wave. The derivation cohort included 494 patients; the median age was 62 and the overall fatality rate was 22.3%. In a multivariable analysis, age, oxygen saturation, neutrophil-to-lymphocyte ratio, C-reactive protein and lactate dehydrogenase were independent predictors of death and composed the score. A cutoff value of 3 demonstrated a sensitivity (Se), specificity (Sp), positive predictive value (PPV) and negative predictive value (NPV) of 93.5%, 68.5%, 47.4% and 97.2% for death, and 84.9%, 84.5%, 79.6% and 87.9% for worsening, respectively. The validation cohort included 415 subjects. The score application showed a Se, Sp, PPV and NPV of 93.4%, 61.6%, 29.5% and 98.1% for death, and 81%, 76.3%, 72.1% and 84.1% for worsening, respectively. We propose a new clinical, easy and reliable score to predict the outcome in hospitalized SARS-CoV-2 patients. 相似文献
90.