全文获取类型
收费全文 | 8439篇 |
免费 | 405篇 |
国内免费 | 471篇 |
专业分类
耳鼻咽喉 | 152篇 |
儿科学 | 117篇 |
妇产科学 | 193篇 |
基础医学 | 823篇 |
口腔科学 | 376篇 |
临床医学 | 1110篇 |
内科学 | 1194篇 |
皮肤病学 | 74篇 |
神经病学 | 409篇 |
特种医学 | 414篇 |
外国民族医学 | 4篇 |
外科学 | 1023篇 |
综合类 | 735篇 |
现状与发展 | 1篇 |
一般理论 | 1篇 |
预防医学 | 529篇 |
眼科学 | 248篇 |
药学 | 756篇 |
2篇 | |
中国医学 | 217篇 |
肿瘤学 | 937篇 |
出版年
2024年 | 1篇 |
2023年 | 229篇 |
2022年 | 255篇 |
2021年 | 389篇 |
2020年 | 437篇 |
2019年 | 283篇 |
2018年 | 243篇 |
2017年 | 217篇 |
2016年 | 216篇 |
2015年 | 372篇 |
2014年 | 612篇 |
2013年 | 551篇 |
2012年 | 767篇 |
2011年 | 764篇 |
2010年 | 600篇 |
2009年 | 524篇 |
2008年 | 433篇 |
2007年 | 485篇 |
2006年 | 364篇 |
2005年 | 291篇 |
2004年 | 231篇 |
2003年 | 173篇 |
2002年 | 170篇 |
2001年 | 147篇 |
2000年 | 127篇 |
1999年 | 101篇 |
1998年 | 91篇 |
1997年 | 42篇 |
1996年 | 42篇 |
1995年 | 19篇 |
1994年 | 18篇 |
1993年 | 31篇 |
1992年 | 32篇 |
1991年 | 15篇 |
1990年 | 16篇 |
1989年 | 15篇 |
1988年 | 7篇 |
1987年 | 3篇 |
1986年 | 2篇 |
排序方式: 共有9315条查询结果,搜索用时 476 毫秒
1.
Yuxiang Ma Wenfeng Fang Hongyun Zhao Sai Praneeth Bathena Amol Tendolkar Jennifer Sheng Li Zhang 《The oncologist》2021,26(4):e549-e566
Lessons Learned
- The overall safety profiles of ipilimumab 3 mg/kg and 10 mg/kg administered every 3 weeks, were consistent between Chinese patients with solid tumors in the current study and patients from previous U.S. ipilimumab monotherapy studies. No new safety signals were identified.
- The mean systemic exposures to ipilimumab (assessed by first dose area under the curve during the dosing interval and maximum serum concentration) were numerically lower in the Chinese patient population than in U.S. patients for both 3 mg/kg and 10 mg/kg doses; however, the range of serum concentrations in the Chinese and U.S. populations overlapped (3 mg/kg and 10 mg/kg), suggesting that ipilimumab pharmacokinetics was ethnically insensitive in this study.
2.
3.
Wang-Shu Zhu Si-Ya Shi Ze-Hong Yang Chao Song Jun Shen 《World journal of gastroenterology : WJG》2020,26(11):1208-1220
BACKGROUND Postoperative liver failure is the most severe complication in cirrhotic patients with hepatocellular carcinoma(HCC) after major hepatectomy. Current available clinical indexes predicting postoperative residual liver function are not sufficiently accurate.AIM To determine a radiomics model based on preoperative gadoxetic acid-enhanced magnetic resonance imaging for predicting liver failure in cirrhotic patients with HCC after major hepatectomy.METHODS For this retrospective study, a radiomics-based model was developed based on preoperative hepatobiliary phase gadoxetic acid-enhanced magnetic resonance images in 101 patients with HCC between June 2012 and June 2018. Sixty-one radiomic features were extracted from hepatobiliary phase images and selected by the least absolute shrinkage and selection operator method to construct a radiomics signature. A clinical prediction model, and radiomics-based model incorporating significant clinical indexes and radiomics signature were built using multivariable logistic regression analysis. The integrated radiomics-based model was presented as a radiomics nomogram. The performances of clinical prediction model, radiomics signature, and radiomics-based model for predicting post-operative liver failure were determined using receiver operating characteristics curve, calibration curve, and decision curve analyses.RESULTS Five radiomics features from hepatobiliary phase images were selected to construct the radiomics signature. The clinical prediction model, radiomics signature, and radiomics-based model incorporating indocyanine green clearance rate at 15 min and radiomics signature showed favorable performance for predicting postoperative liver failure(area under the curve: 0.809-0.894). The radiomics-based model achieved the highest performance for predicting liver failure(area under the curve: 0.894; 95%CI: 0.823-0.964). The integrated discrimination improvement analysis showed a significant improvement in the accuracy of liver failure prediction when radiomics signature was added to the clinical prediction model(integrated discrimination improvement = 0.117, P =0.002). The calibration curve and an insignificant Hosmer-Lemeshow test statistic(P = 0.841) demonstrated good calibration of the radiomics-based model. The decision curve analysis showed that patients would benefit more from a radiomics-based prediction model than from a clinical prediction model and radiomics signature alone.CONCLUSION A radiomics-based model of preoperative gadoxetic acid–enhanced MRI can be used to predict liver failure in cirrhotic patients with HCC after major hepatectomy. 相似文献
4.
5.
目的探讨1 470 nm激光剜除治疗高危前列腺增生的手术技巧及临床效果。
方法回顾分析2018年6月至2018年9月中山大学附属第三医院泌尿外科采用1 470 nm激光治疗共89例高危前列腺增生患者的临床资料,年龄平均(68±3)岁,前列腺体积(57.4±2.6)ml。所有患者均采用"寻找层面,先易后难,剜切结合"的层面递进法思路行激光腔内前列腺剜除术,比较患者术中及术后情况。
结果89例均顺利完成手术,与术前相比,术后3个月患者最大尿流率明显增加,[(6.9±2.1) ml/s vs(19.8±3.6) ml/s]。国际前列腺症状评分显著好转,[(24.6±1.7) vs(8.0±1.2)]。术中无输血、无电切综合征、无直肠和膀胱穿孔病例,无输尿管损伤、大出血、心脑血管意外等严重并发症发生。
结论层面递进法激光剜除技术构想对于高危前列腺增生外科包膜层面的寻找、减少术后并发症有独到优势,且易于掌握,或可为业界同行提供一个新的思路。 相似文献
6.
7.
《Biomaterials》2015
Neural crest stem cells (NCSCs), a population of multipotent cells that migrate extensively and give rise to diverse derivatives, including peripheral and enteric neurons and glia, craniofacial cartilage and bone, melanocytes and smooth muscle, have great potential for regenerative medicine. Non-human primates provide optimal models for the development of stem cell therapies. Here, we describe the first derivation of NCSCs from cynomolgus monkey embryonic stem cells (CmESCs) at the neural rosette stage. CmESC-derived neurospheres replated on polyornithine/laminin-coated dishes migrated onto the substrate and showed characteristic expression of NCSC markers, including Sox10, AP2α, Slug, Nestin, p75, and HNK1. CmNCSCs were capable of propagating in an undifferentiated state in vitro as adherent or suspension cultures, and could be subsequently induced to differentiate towards peripheral nervous system lineages (peripheral sympathetic neurons, sensory neurons, and Schwann cells) and mesenchymal lineages (osteoblasts, adipocytes, chondrocytes, and smooth muscle cells). CmNCSCs transplanted into developing chick embryos or fetal brains of cynomolgus macaques survived, migrated, and differentiated into progeny consistent with a neural crest identity. Our studies demonstrate that CmNCSCs offer a new tool for investigating neural crest development and neural crest-associated human disease and suggest that this non-human primate model may facilitate tissue engineering and regenerative medicine efforts. 相似文献
8.
Queen Garnet plum (QGP), known for its high levels of anthocyanins, is a hybrid of the Japanese plum developed in Queensland, Australia. Anthocyanins provide the red, blue, and purple pigments in plants with demonstrated beneficial health effects. This study hypothesized that low-dose anthocyanin QGP intake will have a significant positive effect on cognition, blood pressure, and gut microbiota in healthy older adults. A randomized crossover trial was conducted to determine the effect and within subject variance on cognition and 24 hr. ambulatory blood pressure in older adults without cognitive impairment following daily consumption of 200 mL low-dose anthocyanin (5 mg/100 g) QGP nectar (intervention) or raspberry cordial (control). Secondary outcomes included inflammatory markers (C-reactive protein), nerve growth factor (BDNF), and gut microbiota (16S rRNA gene sequencing). Twenty-eight participants (55+ years) were recruited. Each randomized treatment arm lasted for 8 weeks with a 4-week washout period. Cognition, blood pressure, and urine samples were measured at each visit (5 total) while blood and fecal samples were collected at baseline, 8 weeks, and 20 weeks. Repeated-measures ANOVA was used to analyze the data. Across the treatments, no significant difference was observed for the different domains of cognition, blood pressure, or anti-inflammatory biomarkers. No intervention effect was found for genera or class of gut microbes. Low anthocyanin nectar derived from the QGP did not have any significant effects on cognition, blood pressure, or gut microbiota in healthy older adults. 相似文献
9.
10.
《Ultrasound in medicine & biology》2019,45(9):2317-2327
The aim of our study was to compare strain elastography (SE), acoustic radiation force impulse-inducing Virtual Touch Imaging ([VTI] Siemens Medical Solutions, Mountain View, CA, USA), Virtual Touch Imaging Quantification ([VTIQ] Siemens Medical Solutions) and combined methods in the evaluation of ultrasound (US) Breast Imaging-Reporting and Data System (BI-RADS) category 4 lesions to explore an applicable way to reduce unnecessary biopsy by reducing false positives of conventional US without yielding false-negative cases. A total of 267 patients with 278 BI-RADS category 4 lesions (151 benign and 127 malignant) were evaluated with conventional B-mode US, SE, VTI and VTIQ implemented on a Siemens Acuson S2000 US system. Diagnostic performance, including area under the receiver operating characteristic curve, sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) were evaluated. Overall, VTI alone exhibited the highest NPV (91.74%), although combined elastic methods exhibited higher NPV than single methods, with the highest NPV at 100% when the VTI, SE and VTIQ methods were combined. Compared with conventional US, PPV increased from 45.7% (127 of 278) to 63.18% (127 of 201) when adding combined elastography (VTI + SE +VTIQ). In addition, 52.5% (63/120) and 50.8% (61/120) of BI-RADS 4 A lesions were downgraded when using combined methods (VTI + SE and VTI + SE + VTIQ, respectively) without missing any cancer. However, 2 intraductal papillomas and 1 phyllodes tumor were not identified. In conclusion, the combination of different elastic methods have the potential to downgrade BI-RADS 4A lesions to reduce false-positive biopsies without increasing the risk of missing cancers. 相似文献