全文获取类型
收费全文 | 17961篇 |
免费 | 1501篇 |
国内免费 | 309篇 |
专业分类
耳鼻咽喉 | 20篇 |
儿科学 | 381篇 |
妇产科学 | 17篇 |
基础医学 | 2566篇 |
口腔科学 | 236篇 |
临床医学 | 1758篇 |
内科学 | 5230篇 |
皮肤病学 | 331篇 |
神经病学 | 139篇 |
特种医学 | 394篇 |
外科学 | 1933篇 |
综合类 | 2220篇 |
现状与发展 | 3篇 |
预防医学 | 501篇 |
眼科学 | 109篇 |
药学 | 2000篇 |
7篇 | |
中国医学 | 1856篇 |
肿瘤学 | 70篇 |
出版年
2024年 | 54篇 |
2023年 | 427篇 |
2022年 | 657篇 |
2021年 | 744篇 |
2020年 | 754篇 |
2019年 | 757篇 |
2018年 | 728篇 |
2017年 | 765篇 |
2016年 | 700篇 |
2015年 | 573篇 |
2014年 | 1144篇 |
2013年 | 2133篇 |
2012年 | 893篇 |
2011年 | 990篇 |
2010年 | 717篇 |
2009年 | 818篇 |
2008年 | 782篇 |
2007年 | 830篇 |
2006年 | 695篇 |
2005年 | 576篇 |
2004年 | 509篇 |
2003年 | 357篇 |
2002年 | 358篇 |
2001年 | 294篇 |
2000年 | 276篇 |
1999年 | 267篇 |
1998年 | 251篇 |
1997年 | 191篇 |
1996年 | 191篇 |
1995年 | 167篇 |
1994年 | 143篇 |
1993年 | 144篇 |
1992年 | 122篇 |
1991年 | 85篇 |
1990年 | 92篇 |
1989年 | 59篇 |
1988年 | 54篇 |
1987年 | 58篇 |
1986年 | 64篇 |
1985年 | 59篇 |
1984年 | 61篇 |
1983年 | 33篇 |
1982年 | 61篇 |
1981年 | 39篇 |
1980年 | 24篇 |
1979年 | 19篇 |
1978年 | 14篇 |
1977年 | 13篇 |
1976年 | 11篇 |
1975年 | 10篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
T. C. WASCHER J. HERMANN R. BREZINSCHEK H. P. BREZINSCHEK M. WILDERS-TRUSCHNIG F. RAINER G. J. KREJS 《European journal of clinical investigation》1994,24(1):73-75
Abstract. Cytokines are major mediators of inflammatory responses in rheumatoid arthritis. Some of them have been shown to correlate with the disease activity and thus are proposed to be used for monitoring patients. Therefore the effects of a low-dose therapy with methotrexate on serum concentrations of interleukin-6 (IL-6) and tumour-necrosis-factor-alpha (TNF-α) were examined in eight patients with seropositive rheumatoid arthritis. Serum levels of IL-6 and TNF-α were significantly elevated in patients compared to healthy controls. Before the onset of MTX treatment IL-6 concentrations were correlated to the c-reactive protein ( P < 0·05) but the correlation was abolished after treatment. For TNF-α no correlations neither before nor after treatment were observed. Both cytokines remained substantially elevated after MTX treatment despite a clear reduction in disease activity. Thus we suggest that one of the effects of MTX might be the inhibition of some of the actions of IL-6 and TNF-α. 相似文献
22.
Summary Among 38 human hybridoma-derived monoclonal rheumatoid factors (RFs) generated from patients with either rheumatoid arthritis (RA) or systemic lupus erythematosus (SLE), two groups of RFs can be identified. Monospecific RFs were derived primarily from patients with RA and are characterized by a binding specificity for IgG3 and/or IgG4. Polyreactive RFs were derived largely from patients with SLE and show a broader pattern of reactivity to all four isotypes of IgG. Neither population of RFs was exclusive to either disease. The binding specificities identified appear to be different from the RFs isolated from patients with mixed cryoglobulinemia and may reflect a different antigen selection mechanism. 相似文献
23.
类风湿性关节炎的肺部表现 总被引:1,自引:0,他引:1
本文对30例类风湿性关节炎患者中合并肺部损害的6例患者进行报道。其肺部的主要临床表现为胸痛、咳嗽、气短、长期低热及呼吸困难。体征主要为肺部干湿性罗音及胸膜摩擦音。胸部X线检查可见胸腔积液、胸膜肥厚粘连,弥漫性间质性肺纤维化、间质性肺炎。实验室检查可有嗜酸性粒细胞增高、类风湿因子阳性、血沉增快、免疫球蛋白增高等。本文并对类风湿性关节炎合并肺部病变的发生机理进行了初步探讨。 相似文献
24.
患者,男,22岁。主因双手近端指间关节对称性肿胀1年于2006年10月20日至我科门诊就诊。患者1年前开始出现双手多个近端指间关节肿胀,无关节痛,无关节活动受限。曾至我院骨科门诊,怀疑为“类风湿性关节炎”,口服滑膜炎冲剂、非甾体类消炎止痛药物,症状持续不缓解。现仍有双手食、中、无名指近端指间关节扁梭形肿胀,中指、无名指明显。肿胀局部无压痛,各关节活动度正常。患者无晨僵,无发热及咽痛。既往患者有下意识掰动手指弄出声响的习惯。查体:一般情况良好。双手食、中、无名指近端指间关节梭形肿胀,关节两侧皮肤增厚,未见苔藓样变(图1 a)。… 相似文献
25.
Piero Volpi Luca Marinoni Corrado Bait Marco Galli Matteo Denti 《Knee surgery, sports traumatology, arthroscopy》2007,15(8):1028-1034
Lateral unicompartmental knee arthroplasty (UKA) is a valid alternative treatment in the event of arthritis confined to the
lateral compartment. This paper examines its indications, technique and short to medium-term results. A total of 159 Miller–Galante
cemented UKA prostheses (Zimmer, Warsaw, Indiana) were implanted consecutively (131 medial and 28 lateral) by the same surgeon.
This study investigates 28 lateral UKAs in 27 patients. Twenty-five implants in 24 patients (including a subject operated
bilaterally) were followed up for 12–60 months. Three patients were discarded on account of to short a follow-up period. The
Hospital for Special Surgery (HSS) knee score was used to compare the pre- and post-operative results of the lateral UKA patients.
The HSS score improved from a pre-op mean of 59.92 (range 48–68) to 88.04 (range 71–95) at the last follow-up. There was a
positive increase in the pain, function and ROM components of the score. The lateral UKA prosthesis can be regarded as a sound
alternative to total knee replacement. Correct patient selection on the basis of optimum surgical indications, however, is
essential.
No benefits of funds were received in support of the study. 相似文献
26.
PURPOSE: To evaluate the effects of dissolvable collagen punctal plugs on the symptoms, tear stability and volume in aqueous deficient dry eyes. METHODS: Sixty-two aqueous deficient dry eye patients of mixed aetiology underwent lacrimal punctal occlusion with dissolvable collagen plugs. The subjects were randomly allocated to one of two treatment groups: group I (n = 36) had their lower puncta occluded and group II (n = 26) had both their upper and lower puncta occluded. The effectiveness of this treatment was clinically assessed by (1). scoring subject symptoms and (2). measuring the tear parameters of tear thinning time (TTT) and tear meniscus height (TMH) as indicators of tear stability and volume, respectively. Following baseline measurements, patients were reviewed at time intervals of 5 and 12 days post-occlusion. A group of age- and gender-matched normals (n = 45) was recruited for comparison (group III). RESULTS: Tear volume and stability were significantly higher in group III compared with I and II at baseline. In the treated groups on both days 5 and 12: (1). symptom score reduced significantly from a median value of 7 to 3 (p = <0.001); (2). tear stability increased significantly from a median value of 3 to 5 s by day 5 (p 相似文献
27.
Debbie Ehrmann Feldman Mirella de Civita Patricia L. Dobkin Pete Malleson Garbis Meshefedjian CiarÁn M. Duffy 《Arthritis care & research》2007,57(2):226-233
Objective
To document perceived adherence to treatment (taking medications and performing exercises) in patients with juvenile idiopathic arthritis (JIA) over a 1‐year period and to identify related factors.Methods
We surveyed parents of patients with JIA at the Montreal Children's Hospital and British Columbia's Children's Hospital in Vancouver. Parents were asked to respond to a series of questionnaires every 3 months over a 12‐month period. Perceived adherence was evaluated on a 100‐mm visual analog scale (VAS) in the Parent Adherence Report Questionnaire (PARQ). Parental coping, distress, child function, disease severity and duration, perceived helpfulness of treatment, problems encountered, and sociodemographic data were also assessed.Results
The mean age of our sample of 175 children was 10.2 years; mean age at diagnosis was 6.1 years and mean disease duration was 4.1 years. Perceived adherence to medications was consistently high, with average adherence at baseline, 3, 6, 9, and 12 months being 86.1, 91.7, 90.4, 92.0, and 88.8, respectively, on the PARQ VAS. Perceived adherence to exercise was lower but remained steady, with corresponding means of 54.5, 64.1, 61.2, 63.0, and 54.3, respectively. Using generalized estimating equation analysis, factors associated with higher perceived adherence to medications included perceived helpfulness of medications and lower disease severity; those associated with higher perceived adherence to exercise were younger age of the child, child involvement in responsibility for treatment, and higher perceived helpfulness of the treatment.Conclusion
Belief in helpfulness of treatment is associated with higher parental perceived adherence to treatment. 相似文献28.
M. Uhl K. H. Allmann C. Ihling M. P. Hauer W. Conca M. Langer 《Skeletal radiology》1998,27(12):677-682
Purpose. To assess the accuracy of different MR sequences for the detection of articular cartilage abnormalities in rheumatoid arthritis.
Design and patients. Ten metacarpophalangeal joints and 10 metatarsophalangeal joints (specimens from arthritis patients undergoing ablative joint
surgery) were examined with a fat-suppressed (FS) 3D FLASH, a FS 3D FISP, a FS 2D fast spin-echo T2-weighted, and a 2D FS
spin-echo T1-weighted sequence. Each cartilage lesion and each cortical lesion was graded from 0 to 4 (modified Outerbridge
staging system). Subsequently, the results of each sequence were compared with the macroscopic findings and statistically
tested against each other. Results. The study shows that 3D gradient-echo sequences with fat suppression were best for imaging and grading of cartilage lesions
in arthritis of the small joints of the hands and feet. Using 3D techniques, all grade 2, grade 3, and grade 4 lesions of
cartilage or cortical bone were detected. Conclusion. FS 3D gradient-echo techniques were best for the detection and grading of hyaline cartilage and subchondral bone lesions
in rheumatoid arthritis. MRI has a great potential as an objective method of evaluating cartilage damage and bone erosions
in rheumatoid arthritis. 相似文献
29.
A. G. TZIOUFAS D. S. BOUMBA † F. N. SKOPOULI D. A. CARSON H. M. MOUTSOPOULOS 《European journal of clinical investigation》1992,22(7):475-481
Abstract. A comparison of the presence of two idiotypes, one identified by a rabbit polyclonal anti-idiotypic antibody, first found on a cryoprecipitable IgM.± rheumatoid factor (RF) from an SS patient (3rd SS) and the 17109 idiotype, identified by a monoclonal antibody was performed in 106 sera and eight minor salivary gland biopsies of Sjögren's syndrome (SS) patients and 125 sera from age-sex matched normal controls. Of 106 of SS patients' sera 36 had immuno-globulins positive for the 3rd SS idiotype. 17109 activity was more prevalent in SS patients positive for the polyclonal anti-idiotype 3rd SS, than those with negative idiotype (9/36 VS 2/70 times2= 12.53 P <0.005). Cross inhibition studies, however, revealed that the polyclonal anti-idiotype binding was not inhibited by the 17109 moAb. 3rd SS and 17109 anti-idiotypes were reacted with immunoglobulins in the serum of 3–5% and 1.7% of normal human sera respectively. Immu-nohistologic studies demonstrated that 4/8 and 2/6 minor salivary gland biopsies had infiltrating plasma cells containing immunoglobulins bearing the 3rd SS and the 17109 idiotypes, respectively. The inheritance of both idiotypes was investigated in sera of 4 SS kindreds. In two kindreds with 3rd SS positive pro-bands, the idiotype was detected in 3 first degree relatives of the same generation. 17109 activity was detected in the serum of a sister of the positive proband who had a high RF titer. These results suggest that the 17109 moAb recognizes a different epitope of that of the 3rd SS. The idiotypes of monoclonal RFs are not inherited and probably are produced by plasma cells infiltrating the labial minor salivary glands of SS patients. 相似文献
30.
Identification and characterization of a DR4-restricted T cell epitope within chlamydia heat shock protein 60 总被引:11,自引:0,他引:11 下载免费PDF全文
K H O DEANE R M JECOCK J H PEARCE J S H GASTON 《Clinical and experimental immunology》1997,109(3):439-445
An epitope within the 60 kD Chlamydia trachomatis heat shock protein (hsp) 60, recognized by a HLA-DRB1*0401-restricted T cell clone from a reactive arthritis patient, has been characterized. Stimulatory peptides contained a nine amino acid sequence (residues 38–46) predicted by algorithm to confer strong binding to DRB1*0401, with valine in the P1 position. The overall length of the peptide was critical for efficient recognition; peptides with at least one residue N-terminal to the putative P1 position were markedly more stimulatory than a peptide whose N-terminal is the P1 valine. Optimal responses were seen with 14mer peptides having two to three amino acids N- and C-terminal to the core 9mer. The sequence of the defined epitope is identical in hsp60 from both C. trachomatis and C. pneumoniae. Since the latter is a common respiratory pathogen, patients infected with C. trachomatis may already be primed for responses to hsp60 by prior infection with C. pneumoniae. Such secondary responses are important in the pathogenesis of chlamydia-induced inflammatory diseases such as trachoma. Priming by infection with enteric organisms was considered because of the similarity of the epitope sequence in Escherichia coli hsp60. However, although an E. coli-related peptide was recognized, intact E. coli hsp60 was not, suggesting that the epitope is cryptic in E. coli hsp60. Human hsp60 has six amino acid differences from chlamydial hsp60 in the epitope sequence and was not recognized. Thus cross-reactive recognition of self hsp60 could not be implicated in the pathogenesis of chlamydia-induced reactive arthritis in this patient. 相似文献