全文获取类型
收费全文 | 7912篇 |
免费 | 292篇 |
国内免费 | 26篇 |
专业分类
耳鼻咽喉 | 368篇 |
儿科学 | 275篇 |
妇产科学 | 374篇 |
基础医学 | 1045篇 |
口腔科学 | 53篇 |
临床医学 | 466篇 |
内科学 | 1909篇 |
皮肤病学 | 116篇 |
神经病学 | 674篇 |
特种医学 | 163篇 |
外科学 | 743篇 |
综合类 | 39篇 |
一般理论 | 2篇 |
预防医学 | 423篇 |
眼科学 | 286篇 |
药学 | 982篇 |
中国医学 | 10篇 |
肿瘤学 | 302篇 |
出版年
2023年 | 32篇 |
2022年 | 113篇 |
2021年 | 270篇 |
2020年 | 97篇 |
2019年 | 163篇 |
2018年 | 250篇 |
2017年 | 183篇 |
2016年 | 173篇 |
2015年 | 171篇 |
2014年 | 283篇 |
2013年 | 416篇 |
2012年 | 551篇 |
2011年 | 652篇 |
2010年 | 326篇 |
2009年 | 199篇 |
2008年 | 432篇 |
2007年 | 471篇 |
2006年 | 527篇 |
2005年 | 479篇 |
2004年 | 525篇 |
2003年 | 462篇 |
2002年 | 415篇 |
2001年 | 165篇 |
2000年 | 162篇 |
1999年 | 90篇 |
1998年 | 41篇 |
1997年 | 25篇 |
1996年 | 21篇 |
1995年 | 15篇 |
1994年 | 18篇 |
1993年 | 13篇 |
1992年 | 14篇 |
1991年 | 14篇 |
1990年 | 13篇 |
1989年 | 12篇 |
1988年 | 14篇 |
1987年 | 12篇 |
1985年 | 21篇 |
1984年 | 11篇 |
1983年 | 11篇 |
1982年 | 19篇 |
1980年 | 17篇 |
1979年 | 11篇 |
1978年 | 14篇 |
1977年 | 22篇 |
1975年 | 29篇 |
1974年 | 16篇 |
1973年 | 11篇 |
1955年 | 29篇 |
1954年 | 99篇 |
排序方式: 共有8230条查询结果,搜索用时 31 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.
5.
Agata Cieślik-Bielecka Paweł Reichert Rafał Skowroński Tomasz Bielecki 《Platelets》2019,30(6):728-736
The current literature suggests that the antibacterial effect of leukocyte- and platelet-rich plasma (L-PRP) is directly related to platelet and leukocyte concentrations. The aim of this study was twofold: first, to evaluate the antimicrobial effect of L-PRP against selected bacterial strains in vitro, and second, to correlate this effect with leukocyte and platelet content in the final concentration. Blood was collected from 20 healthy males, and L-PRP, acellular plasma (AP), and autologous thrombin were consecutively prepared. Flow cytometry analysis of the blood, L-PRP, and AP was performed. The L-PRP gel, liquid L-PRP, and thrombin samples were tested in vitro for their antibacterial properties against seven selected bacterial strains using the Kirby–Bauer disk-diffusion method. There was notable antimicrobial activity against selected bacterial strains. No statistically significant correlations between antimicrobial activities and the platelet concentration in L-PRP were observed. Statistically significant positive correlations between selected leukocyte subtypes and antimicrobial activity were noted. A negative correlation was found between elevated monocyte count and antimicrobial activity of L-PRP against one bacterial strain studied. L-PRP possesses antimicrobial activity and can be potentially useful in the fight against certain postoperative infections. The bactericidal effect of L-PRP is caused by leukocytes, and there exists a relationship among selected leukocyte subtypes and L-PRP antimicrobial activity. 相似文献
6.
7.
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
8.
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
9.
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
10.
Kamil Torres Anna Torres Grzegorz J. Staśkiewicz Andrzej Chrościcki Tadeusz Łoś Ryszard Maciejewski 《Surgical endoscopy》2009,23(9):2117-2123
Background Surgical procedures enhance production of pro- and anti-inflammatory cytokines and angiogenic factors that play a pivotal
role in the immunological response to surgical trauma and take part in the pathogenesis of tumor growth and adhesions formation.
The purpose of the study was to access the influence of low-pressure CO2 pneumoperitoneum on the inflammatory and angiogenic responses during the postoperative period after laparoscopy.
Methods The study group consisted of 40 patients, operated on due to cholelithiasis using standard-pressure (n = 20) and low-pressure (n = 20) CO2 pneumoperitoneum. Serum concentration of interleukin (IL)-6, IL-8, IL-10, vascular endothelial growth factor (VEGF)-A, and
endostatin were measured before and at 6, 24, and 48 h after surgery with commercially available enzyme-linked immunosorbent
assay (ELISA).
Results Concentrations of IL-6 increased significantly after the operations in both groups. No differences were observed between the
groups in regards to IL-6, IL-8, and IL-10 levels. Concentrations of VEGF-A measured at 6 and 48 h were significantly lower
in patients who underwent laparoscopies performed with low-pressure pneumoperitoneum. No significant variations were observed
in endostatin serum concentration. Concentrations of the studied parameters were not influenced by duration of surgery or
by age, gender, or body mass index (BMI) of the patients.
Conclusions The results obtained in our study do not show any significant differences between studied operative procedures with regards
to systemic inflammatory response. Changes in the concentrations of VEGF-A and endostatin observed in the studied population
may suggest this technique is more favorable with regards to angiogenesis process intensity, along with all its consequences
and implications. 相似文献