首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   4444篇
  免费   183篇
  国内免费   12篇
耳鼻咽喉   103篇
儿科学   193篇
妇产科学   213篇
基础医学   696篇
口腔科学   33篇
临床医学   266篇
内科学   999篇
皮肤病学   69篇
神经病学   388篇
特种医学   69篇
外科学   198篇
综合类   26篇
预防医学   373篇
眼科学   118篇
药学   597篇
中国医学   15篇
肿瘤学   283篇
  2024年   7篇
  2023年   31篇
  2022年   203篇
  2021年   303篇
  2020年   107篇
  2019年   134篇
  2018年   145篇
  2017年   130篇
  2016年   154篇
  2015年   154篇
  2014年   205篇
  2013年   286篇
  2012年   366篇
  2011年   373篇
  2010年   199篇
  2009年   149篇
  2008年   240篇
  2007年   313篇
  2006年   278篇
  2005年   261篇
  2004年   193篇
  2003年   186篇
  2002年   146篇
  2001年   15篇
  2000年   7篇
  1999年   4篇
  1998年   6篇
  1997年   11篇
  1996年   6篇
  1995年   5篇
  1992年   1篇
  1991年   2篇
  1990年   2篇
  1988年   1篇
  1987年   1篇
  1981年   1篇
  1978年   3篇
  1977年   1篇
  1976年   3篇
  1975年   1篇
  1974年   1篇
  1973年   1篇
  1972年   2篇
  1968年   1篇
  1965年   1篇
排序方式: 共有4639条查询结果,搜索用时 15 毫秒
81.
One of the basic rules of transfusion is to prevent alloimmunisation by highly immunogenic RhD antigen and not to transfuse RhD negative individuals with RhD positive blood. In some cases the expression of this antigen is so weak that it is undetectable in routine serological tests. The paper presents an algorithm for mass DNA testing with the purpose of identifying donors with low RhD expression. The screening is based on RHD gene detection (absent in RhD negative Caucasians) in DNA isolated from pools of 96 plasma samples from blood donors identified as RhD negative by the routine serological methods in Blood Transfusion Centers. Such procedure substantially reduces the costs. Plasma samples can be brought from the territory of the whole country, stored and accumulated for testing in one selected center. The cost would amount to approximately 25 PLN per donor. The test is performed once for each RhD negative individual. It is estimated that such persons will represent approximately 0.2% of RhD negative donors.  相似文献   
82.
Bruton's tyrosine kinase (BTK) is a central mediator of B-cell receptor (BCR) signaling essential for normal B-cell development. Ibrutinib is an oral BTK inhibitor that induces apoptosis and inhibits migration and adhesion of malignant B-cells. Updated results of this international, multicenter, phase 2 study of single agent ibrutinib in relapsed or refractory MCL will be presented.Ibrutinib 560 mg PO QD was administered continuously until disease progression. Tumor response was assessed every 2 cycles (one cycle = 28 days). The study enrolled 115 patients (65 bortezomib-naïve, 50 bortezomib-exposed); 111 patients were treated; 110 were evaluable for response. Baseline characteristics included: median age 68 years, time since diagnosis 42 months, number of prior treatments 3; bulky disease (>10 cm) 13%, prior stem cell transplant 10%, high risk MIPI 49%.Median time on treatment was 9.2 months; 53% of patients remain on therapy. Median PFS was 13.9 months and DOR has not yet been reached. Responses increased with longer treatment: comparing to previous data described at ASH 2011, the CR rate increased from 16% to 39%, and the ORR increased from 69% to 75%.  相似文献   
83.
IntroductionThe aim of the study was to evaluate the correlation between the nutritional status of patients with anorexia nervosa (AN) and levels of vaspin (VASP), neuropeptide B (NPB), neuropeptide W (NPW) and total antioxidant status (TAS).Material and methodsNinety serum samples collected from 30 teenage female patients during the acute stage of AN and 30 healthy persons (CONTR) were subjected to biochemical analysis; patients with AN were examined at the beginning of the study (AN-I) and after hospitalization (AN-II), as a result of which partial stabilization of anthropometric measurements was achieved (an increase of body mass index (BMI) by 3.5 kg/m2).ResultsVaspin levels dropped at the end of the hospitalization (compared to AN-I, p < 0.05), achieving values comparable to the CONTR; moreover there was a positive correlation between VASP level and the achieved body weight in AN-II (p < 0.05). Positive correlations were also noted with regard to VASP vs. NPB in AN-I (p < 0.02) (and AN-II, p < 0.013), as well as in the case of VASP vs. NPW in the same groups (p < 0.02 and p < 0.015, respectively). NPB concentration was higher in AN-I (p < 0.05) and AN-II (p < 0.018) than in CONTR, whereas there were no differences (p > 0.05) with regard to levels of VASP, NPW, or TAS.ConclusionsThe high level of NPB despite treatment and normalization of VASP level may suggest that there are chronic neuroendocrine disorders at play in anorexia nervosa.  相似文献   
84.
IntroductionImmunoglobulin A nephropathy (IgAN) may lead to end stage renal disease and severely affect patient functioning and wellbeing. The aim of the study was to evaluate health-related quality of life (HRQoL) in children and adolescents with IgAN, and compare HRQoL in relation to the disease course, social status and psychological factors, such as expressing anger and perceived personal competence.Material and methodsThe multicentre cross-sectional study included 51 patients ≥ 8 years from 7 paediatric nephrology centres in Poland. Psychometric analysis was performed using the Kidscreen-52 questionnaire to evaluate HRQoL, the Anger Expression Scale to evaluate the severity of anger and the Personal Competence Scale to measure general perception of personal competence.ResultsMean age of patients was 14.54 ±3.69 years; duration since the diagnosis of IgAN was 4.98 ±3.9 years. Patients with IgAN rated their psychological wellbeing as significantly worse compared to healthy peers (p < 0.05). The presence of proteinuria was associated with significantly worse physical wellbeing (58.72 ±18.45 vs. 74.44 ±22.97; p < 0.05). Current therapy (steroids/immunosuppressive drugs) had no effect on HRQoL in the study group. Perceived personal competence was rated high by 49% of children in the study group. Children with IgAN were characterized by lower intensity of expressed anger (p < 0.001) and significantly higher intensity of suppressed anger (p < 0.01) compared to reference ranges. Severity of expressed anger correlated positively with the parent relations and school environment dimensions of HRQoL.ConclusionsWe found lower HRQoL in regard to physical and psychological wellbeing in a group of Polish children with IgAN compared to healthy peers. HRQoL should be monitored in this patient group.  相似文献   
85.
IntroductionPrimary arthroplasty of the hip joint is currently one of the most commonly performed procedures in orthopedics. In Poland we are observing significant changes in the age structure. With the prolonged life more and more elderly patients require musculoskeletal surgery to maintain comfortable and painless mobility. Reducing the duration of the procedure reduces the costs of anesthesiology, surgical and instrument teams, as well as the operating room technical team. The aim of the study was to compare the time required to perform hip joint arthroplasty by the direct anterior approach (DAA) with the postero-lateral approach (PLA) in our hospital.Material and methodsA retrospective analysis of 559 total and bipolar cemented and cementless hip replacement procedures based on two operative approaches – the minimally invasive DAA over the course of 2 years, and the standard PLA over the course of 3 years – was performed.ResultsStatistically significant differences were observed between the approaches used for cementless total arthroplasty with regard to the mean treatment times: 51.9 min for the 272 DAA cases, and 78.3 min for the 190 PLA cases (p < 0.0001). For the cementless hemi-arthroplasty procedure, the mean treatment times were 46.9 min in 36 patients for DAA, and 48.2 min for 61 patients for PLA (p = 0.57).ConclusionsMinimally invasive DAA significantly shortens the time of the procedure in elderly patients compared to PLA. Further study is needed to analyze other aspects of those two approaches.  相似文献   
86.
IntroductionThe misbalance between a family of inhibitor of apoptosis proteins (IAP), regulated by the nuclear factor kappa B (NF-κB) and their natural antagonist second mitochondrial-derived activator of caspases/direct IAP binding protein with low pI (Smac/DIABLO) are important to biology of acute myeloid leukemia (AML).Material and methodsThe aim of the study was to assess NF-κB and Smac/DIABLO proteins expression in blasts of 109 newly diagnosed AML patients using the multicolor flow cytometry and evaluate their influence on AML patients outcome.ResultsExpression of NF-κB and of Smac/DIABLO proteins were found in 95% and 98% of the patients, respectively. A negative correlation between Smac/DIABLO and NF-κB was observed. Age < 60 years old as well as higher Smac/DIABLO expression were associated with a higher probability of complete response achievement in the multivariate analysis. Longer overall survival (OS) in the univariate and multivariate analyses was influenced by age < 60 years old, a favorable or intermediate-risk karyotype and high Smac/DIABLO expression. Additionally, in the survival analysis of the subgroups, the patients aged < 60 years old, with high Smac/DIABLO expression, lower NF-κB expression and < 50% of bone marrow blasts who were treated with standard treatment had better OS.ConclusionsLower NF-κB and higher Smac/DIABLO expression may influence AML patients outcome.  相似文献   
87.
88.
89.
Over the last decade, great progress has been made in the field of organic electronics. Advancements in organic syntheses as well as in device engineering enabled preparation of polymer solar cells with power conversion efficiency (PCE) exceeding 8%–9%. In search for new polymers suitable for photovoltaic applications, push–pull polymers containing thieno[3,4‐c]pyrrole‐4,6‐dione (TPD) motif as an electron deficient (pull) unit emerged as very promising candidates. This Trend Article summarizes research on TPD‐based polymers with a special emphasis on the structure–property relationships.  相似文献   
90.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号