全文获取类型
收费全文 | 53029篇 |
免费 | 5671篇 |
国内免费 | 49篇 |
专业分类
耳鼻咽喉 | 367篇 |
儿科学 | 1609篇 |
妇产科学 | 1459篇 |
基础医学 | 7411篇 |
口腔科学 | 1058篇 |
临床医学 | 6227篇 |
内科学 | 9947篇 |
皮肤病学 | 726篇 |
神经病学 | 5030篇 |
特种医学 | 2106篇 |
外国民族医学 | 3篇 |
外科学 | 7157篇 |
综合类 | 1113篇 |
一般理论 | 57篇 |
预防医学 | 6032篇 |
眼科学 | 1152篇 |
药学 | 3732篇 |
中国医学 | 50篇 |
肿瘤学 | 3513篇 |
出版年
2021年 | 866篇 |
2020年 | 487篇 |
2019年 | 836篇 |
2018年 | 893篇 |
2017年 | 692篇 |
2016年 | 769篇 |
2015年 | 817篇 |
2014年 | 1144篇 |
2013年 | 1791篇 |
2012年 | 2479篇 |
2011年 | 2510篇 |
2010年 | 1421篇 |
2009年 | 1377篇 |
2008年 | 2257篇 |
2007年 | 2383篇 |
2006年 | 2355篇 |
2005年 | 2361篇 |
2004年 | 2265篇 |
2003年 | 2115篇 |
2002年 | 2028篇 |
2001年 | 1800篇 |
2000年 | 1844篇 |
1999年 | 1621篇 |
1998年 | 663篇 |
1997年 | 586篇 |
1996年 | 569篇 |
1995年 | 479篇 |
1994年 | 522篇 |
1993年 | 501篇 |
1992年 | 1237篇 |
1991年 | 1195篇 |
1990年 | 1172篇 |
1989年 | 1084篇 |
1988年 | 1022篇 |
1987年 | 988篇 |
1986年 | 925篇 |
1985年 | 964篇 |
1984年 | 783篇 |
1983年 | 620篇 |
1982年 | 428篇 |
1981年 | 424篇 |
1980年 | 377篇 |
1979年 | 669篇 |
1978年 | 517篇 |
1977年 | 396篇 |
1976年 | 406篇 |
1974年 | 460篇 |
1973年 | 400篇 |
1972年 | 420篇 |
1971年 | 382篇 |
排序方式: 共有10000条查询结果,搜索用时 343 毫秒
1.
2.
3.
Christopher Teng JiaDe Yu Jesse Taylor Adam I. Rubin James R. Treat 《Pediatric dermatology》2019,36(5):697-701
Erosive pustular dermatosis of the scalp (EPDS) is an uncommon chronic inflammatory response to scalp trauma that usually resolves with cicatricial alopecia. It most commonly affects elderly patients with a history of actinic damage. Herein, we describe a 16‐year‐old girl with acrofacial dysostosis type 1 presenting after surgery with crusting purulent scalp lesions, whose clinical presentation and histopathologic findings were consistent with EPDS. A review of the literature on EPDS in children is also detailed. 相似文献
4.
5.
Krishna Pillai Javid Akhter Terence C. Chua Mena Shehata Nayef Alzahrani Issan Al-Alem David L. Morris 《Medicine》2015,94(9)
Thermal ablation of liver tumors near large blood vessels is affected by the cooling effect of blood flow, leading to incomplete ablation. Hence, we conducted a comparative investigation of heat sink effect in monopolar (MP) and bipolar (BP) radiofrequency ablation (RFA), and microwave (MW) ablation devices.With a perfused calf liver, the ablative performances (volume, mass, density, dimensions), with and without heat sink, were measured. Heat sink was present when the ablative tip of the probes were 8.0 mm close to a major hepatic vein and absent when >30 mm away. Temperatures (T1 and T2) on either side of the hepatic vein near the tip of the probes, heating probe temperature (T3), outlet perfusate temperature (T4), and ablation time were monitored.With or without heat sink, BP radiofrequency ablated a larger volume and mass, compared with MP RFA or MW ablation, with latter device producing the highest density of tissue ablated. MW ablation produced an ellipsoidal shape while radiofrequency devices produced spheres.Percentage heat sink effect in Bipolar radiofrequency : Mono-polar radiofrequency : Microwave was (Volume) 33:41:22; (mass) 23:56:34; (density) 9.0:26:18; and (relative elipscity) 5.8:12.9:1.3, indicating that BP and MW devices were less affected.Percentage heat sink effect on time (minutes) to reach maximum temperature (W) = 13.28:9.2:29.8; time at maximum temperature (X) is 87:66:16.66; temperature difference (Y) between the thermal probes (T3) and the temperature (T1 + T2)/2 on either side of the hepatic vessel was 100:87:20; and temperature difference between the (T1 + T2)/2 and temperature of outlet circulating solution (T4), Z was 20.33:30.23:37.5.MW and BP radiofrequencies were less affected by heat sink while MP RFA was the most affected. With a single ablation, BP radiofrequency ablated a larger volume and mass regardless of heat sink. 相似文献
6.
7.
Weiyu Ye Anna Olsson-Brown Robert A. Watson Vincent T. F. Cheung Robert D. Morgan Isar Nassiri Rosalin Cooper Chelsea A. Taylor Umair Akbani Oliver Brain Rubeta N. Matin Nicholas Coupe Mark R. Middleton Mark Coles Joseph J. Sacco Miranda J. Payne Benjamin P. Fairfax 《British journal of cancer》2021,124(10):1661
Background Immune checkpoint blockers (ICBs) activate CD8+ T cells, eliciting both anti-cancer activity and immune-related adverse events (irAEs). The relationship of irAEs with baseline parameters and clinical outcome is unclear.Methods Retrospective evaluation of irAEs on survival was performed across primary (N = 144) and secondary (N = 211) independent cohorts of patients with metastatic melanoma receiving single agent (pembrolizumab/nivolumab—sICB) or combination (nivolumab and ipilimumab—cICB) checkpoint blockade. RNA from pre-treatment and post-treatment CD8+ T cells was sequenced and differential gene expression according to irAE development assessed.Results 58.3% of patients developed early irAEs and this was associated with longer progression-free (PFS) and overall survival (OS) across both cohorts (log-rank test, OS: P < 0.0001). Median survival for patients without irAEs was 16.6 months (95% CI: 10.9–33.4) versus not-reached (P = 2.8 × 10−6). Pre-treatment monocyte and neutrophil counts, but not BMI, were additional predictors of clinical outcome. Differential expression of numerous gene pathway members was observed in CD8+ T cells according to irAE development, and patients not developing irAEs demonstrating upregulated CXCR1 pre- and post-treatment.Conclusions Early irAE development post-ICB is associated with favourable survival in MM. Development of irAEs is coupled to expression of numerous gene pathways, suggesting irAE development in-part reflects baseline immune activation.Subject terms: Immunotherapy, Melanoma 相似文献
8.
Sweeka Alexander Gurjeet Dulku Sharbell Hashoul Donna B Taylor 《Journal of Medical Imaging and Radiation Oncology》2019,63(4):473-478
Contrast‐enhanced spectral mammography (CESM) has a number of uses including the work‐up of inconclusive findings on mammography, assessment of breast symptoms, cancer staging, evaluation of response to neoadjuvant chemotherapy and recently as an alternative to magnetic resonance imaging (MRI) in high‐risk screening. CESM can be swiftly incorporated into the workflow of busy breast clinics. We share our experiences with CESM at a large breast assessment centre in Western Australia. 相似文献
9.
10.
O. Morris M. Fairclough J. Grigg C. Prenant A. McMahon 《Journal of labelled compounds & radiopharmaceuticals》2019,62(1):4-23
Affinity peptide and protein‐ (APP) based radiotracers are an increasingly popular class of radiotracer in positron emission tomography (PET), which was once dominated by the use of small molecule radiotracers. Radiolabelled monoclonal antibodies (mAbs) are important examples of APPs, yet a preference for smaller APPs, which exhibit fast pharmacokinetics and permit rapid PET aided diagnosis, has become apparent. 18F exhibits favourable physical characteristics for APP radiolabelling and has been described as an ideal PET radionuclide. Notwithstanding, 18F radiolabelling of APP is challenging, and this is echoed in the literature where a number of diverse approaches have been adopted. This review seeks to assess and compare the approaches taken to 18F APP radiolabelling with the intention of highlighting trends within this expanding field. Generic themes have emerged in the literature, namely the use of mild radiolabelling conditions, a preference of site‐specific methodologies with an impetus for short, automated procedures which produce high‐yielding [18F]APPs. 相似文献