全文获取类型
收费全文 | 4562篇 |
免费 | 197篇 |
国内免费 | 22篇 |
专业分类
耳鼻咽喉 | 217篇 |
儿科学 | 126篇 |
妇产科学 | 175篇 |
基础医学 | 542篇 |
口腔科学 | 17篇 |
临床医学 | 376篇 |
内科学 | 1200篇 |
皮肤病学 | 76篇 |
神经病学 | 427篇 |
特种医学 | 87篇 |
外科学 | 489篇 |
综合类 | 42篇 |
一般理论 | 3篇 |
预防医学 | 235篇 |
眼科学 | 128篇 |
药学 | 413篇 |
中国医学 | 2篇 |
肿瘤学 | 226篇 |
出版年
2023年 | 21篇 |
2022年 | 25篇 |
2021年 | 256篇 |
2020年 | 72篇 |
2019年 | 95篇 |
2018年 | 130篇 |
2017年 | 101篇 |
2016年 | 87篇 |
2015年 | 101篇 |
2014年 | 151篇 |
2013年 | 224篇 |
2012年 | 332篇 |
2011年 | 389篇 |
2010年 | 184篇 |
2009年 | 150篇 |
2008年 | 282篇 |
2007年 | 311篇 |
2006年 | 334篇 |
2005年 | 326篇 |
2004年 | 306篇 |
2003年 | 257篇 |
2002年 | 228篇 |
2001年 | 36篇 |
2000年 | 37篇 |
1999年 | 32篇 |
1998年 | 32篇 |
1997年 | 20篇 |
1996年 | 18篇 |
1995年 | 11篇 |
1994年 | 17篇 |
1993年 | 19篇 |
1992年 | 20篇 |
1991年 | 13篇 |
1990年 | 14篇 |
1989年 | 17篇 |
1988年 | 10篇 |
1987年 | 14篇 |
1986年 | 8篇 |
1985年 | 12篇 |
1984年 | 7篇 |
1983年 | 6篇 |
1982年 | 9篇 |
1980年 | 6篇 |
1979年 | 4篇 |
1978年 | 5篇 |
1977年 | 10篇 |
1975年 | 5篇 |
1973年 | 5篇 |
1968年 | 6篇 |
1966年 | 3篇 |
排序方式: 共有4781条查询结果,搜索用时 535 毫秒
1.
Jakub Pazdrowski Aleksandra Daczak‐Pazdrowska Adriana Polaska Joanna Ka
mierska Wojciech Barczak Mateusz Szewczyk Pawe Golusiski Zygmunt Adamski Ryszard aba Wojciech Golusiski 《Skin research and technology》2019,25(6):857-861
Radiodermatitis is one of the commonest side effects of radiotherapy. They are usually assessed by semi‐quantitative clinical scores, which are not validated and may be subject to inter‐observer variability. A few previous studies suggested that high‐frequency ultrasonography (HF‐USG) is useful in the assessment of the acute phase of radiation dermatitis in breast cancer patients. (a) To monitor skin changes by HF‐USG during the course of radiotherapy due to head and neck cancers, and (b) to determine whether there is any connection between skin sonograms and the skin scoring criteria. This prospective, observational study includes patients diagnosed with head and neck cancers, treated with radiotherapy or concomitant chemoradiation. The final analysis includes six patients. In every patient, the HF‐USG as well as dermatological assessment (target lesion score—TLS and CACE v. 4.0) were performed 4×: before, in the middle, day after, and 3 months after radiotherapy. There were significant differences between non‐irradiated skin thickness and thickness of skin with clinically obvious radiodermatitis (TLS grade 1‐4; P < .0001), as well as between irradiated, unchanged skin thickness (TLS grade 0) and thickness of skin with clinically obvious radiodermatitis (TLS grade 1‐4; P = .0002). There was no significant difference between non‐irradiated and irradiated, unchanged skin thickness (TLS grade 0; P = .9318). In four patients, we demonstrated subepidermal low echogenic band (SLEB). HF‐USG can be useful tool to noninvasive and objective assessment of skin changes during radiotherapy. 相似文献
2.
Wojciech Szychta M.D. Ph.D. Gheorghe Cerin M.D. Ph.D. F.E.S.C. Bogdan Adrian Popa M.D. Armienti Felice M.D. Guido Lanzillo M.D. Ph.D. Marco Diena M.D. Grzegorz Opolski M.D. Ph.D. F.E.S.C. 《Echocardiography (Mount Kisco, N.Y.)》2015,32(6):1040-1043
Sinus venosus atrial septal defect (SV‐ASD) usually coexists with partial anomalous pulmonary vein connection (PAPVC). It is a difficult diagnosis in transthoracic echocardiography (TTE) due to eccentric position of defects. We present a rare case of atypical anatomical variation in PAPVC, which was never described before. Two right pulmonary veins drained into superior vena cava, which overrode SV‐ASD and interatrial septum, a third pulmonary vein into the right atrium. Complete diagnosis could not be set after TTE, nor transesophageal echocardiography, whereas angio‐CT was finally conclusive. This diagnostic approach allowed the surgical planning. 相似文献
3.
4.
Jaros?aw Felu? Wojciech Rad?o Bart?omiej Kowalczyk 《Chirurgia narzadów ruchu i ortopedia polska》2006,71(2):107-112
Nine wrists in eight patients were treated surgically between 1988 and 2003 for symptomatic Madelung's deformity. The pain of involved wrist followed by forearm deformation fulfilled criteria for surgery. Closing wedge osteotomy of the distal radius were carried out eight times accompanied by shortening of the ulna (four patients), excision of the distal ulna (one patient), and no ulnar surgery (three patients). Pain relieved after surgery. The follow up period ranged from 1 to 9.5 years. No pour results were stated in subjective patient's estimation during final check up. Wrist appearance were stated to be satisfactory. Limitation of the range of motion concerning supination and pronation of the forearm were stated invariably. X-ray retrospective assessment of the inclination angle, lunate coverage and presence of arthritic changes were conducted. Time and method of surgical treatment for Madelung's deformity should be considered individually. 相似文献
5.
Wojciech Krzysztof Czerwinski 《Macromolecular chemistry and physics.》1991,192(6):1285-1296
Initiation constant 2kd · f, dissociation constant kd, and efficiency factor f of AIBN were measured at 60°C for two model homopolymerization systems: methyl methacrylate (MMA) in N-methyl-2-pyrrolidone (NMP) and N-vinyl-2-pyrrolidone (NVP) in methyl isobutyrate (MiB) as the solvent. The stable Banfield radical was used as inhibitor. A pronounced solvent effect was observed on the side reaction of the inhibitor with the monomers. Particular solvent sensitivity of monomers in this reaction was identified, whereby opposite solvent properties of NMP and MiB as well as of MMA and NVP were found. The initiation constant 2 kd · f depends mainly on the dissociation constant of the initiator kd in regard to its solvent dependence. The efficiency factor f is influenced by monomer concentration, stability (reactivity) of primary radicals and by viscosity of the reaction medium (solvent cage effect). 相似文献
6.
Pawel Kaluzny Remigiusz Tarnecki Wojciech Zmyslowski 《Journal of neuroscience methods》1991,40(2-3):149-153
The principal-component approach is applied to the analysis of sequences of neuronal action potentials (spike trains). Multiple spike trains are represented as a sequence of vectors of mutual interspike intervals and are considered to be part of the trajectory of a dynamic system. The trajectory matrix is decomposed into a number of ‘basic spike patterns’ and their relative magnitudes by singular-value decomposition. The representation provides a convenient framework for analysis of dynamic relations and cooperation between neurons in an observed network. Examples of applications to simulated and cerebellar data are presented. 相似文献
7.
8.
9.
Fix Joseph A. Alexander Jose Cortese Margot Engle Karen Leppert Paula Repta A. J. 《Pharmaceutical research》1990,7(4):384-387
Short-chain alkyl esters of L-dopa were administered to rats and mice via oral and rectal routes. Plasma L-dopa esters and L-dopa were determined in the systemic and portal circulation by HPLC. A comparison of isopropyl, butyl, and 4-hydroxybutyl esters of L-dopa demonstrated significantly higher levels of the esters in both systemic and portal blood samples following rectal administration than following oral administration. In most cases, oral administration resulted in nondetectable (<0.01 µg/ml) levels of the esters in plasma. Correspondingly, the plasma levels of L-dopa itself were consistently higher following rectal administration. At very high oral doses (500 mg L-dopa equivalents/kg body weight), systemic plasma levels of the butyl ester could be detected (1.25 µg/ml at 10 min), which might indicate saturation of the esterase activity of the small intestine. These studies indicate that the systemic availability of L-dopa from short-chain alkyl esters of L-dopa may be best optimized by rectal administration, which avoids the relatively high esterase activity characteristic of the small intestine. 相似文献
10.