全文获取类型
收费全文 | 742篇 |
免费 | 42篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 8篇 |
儿科学 | 22篇 |
妇产科学 | 17篇 |
基础医学 | 118篇 |
口腔科学 | 5篇 |
临床医学 | 74篇 |
内科学 | 209篇 |
皮肤病学 | 4篇 |
神经病学 | 79篇 |
特种医学 | 16篇 |
外科学 | 67篇 |
综合类 | 1篇 |
预防医学 | 88篇 |
眼科学 | 27篇 |
药学 | 24篇 |
肿瘤学 | 30篇 |
出版年
2023年 | 2篇 |
2022年 | 12篇 |
2021年 | 18篇 |
2020年 | 8篇 |
2019年 | 13篇 |
2018年 | 15篇 |
2017年 | 13篇 |
2016年 | 24篇 |
2015年 | 30篇 |
2014年 | 33篇 |
2013年 | 45篇 |
2012年 | 59篇 |
2011年 | 52篇 |
2010年 | 25篇 |
2009年 | 33篇 |
2008年 | 51篇 |
2007年 | 54篇 |
2006年 | 35篇 |
2005年 | 31篇 |
2004年 | 49篇 |
2003年 | 36篇 |
2002年 | 49篇 |
2001年 | 13篇 |
2000年 | 12篇 |
1999年 | 10篇 |
1998年 | 6篇 |
1997年 | 7篇 |
1996年 | 8篇 |
1995年 | 3篇 |
1994年 | 11篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1991年 | 3篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 4篇 |
1986年 | 5篇 |
1985年 | 4篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1973年 | 1篇 |
1971年 | 1篇 |
排序方式: 共有789条查询结果,搜索用时 31 毫秒
1.
Steve Ramcharitar Mark S Patterson Robert J van Geuns Martin van der Ent Georgios Sianos Gijs M J M Welten Ron T van Domburg Patrick W Serruys 《Catheterization and cardiovascular interventions》2007,70(5):662-668
OBJECTIVES: To directly compare the magnetic navigation system (MNS) guidewires with conventional guidewires in branching tortuous phantoms with operators of varying MNS and percutaneous coronary intervention experience. BACKGROUND: Vessel tortuosity, angulation, and side branches remain limiting factors in coronary interventions. The MNS addresses these limitations by precisely directing the tip of a magnetised guidewire in vivo aided by two permanent adjustable external magnets. METHODS: Crossing and fluoroscopy times of six operators were evaluated in five tortuous Perspex(R) phantom vessels in three consecutive attempts. Standard guidewire (SG) usage was unrestricted. Two 2nd generation magnetic guidewires (MG) were used. Failure was noted if the cross was unsuccessful within 5 min. RESULTS: The magnetic navigation was vastly superior to SG techniques with increasingly tortuous phantoms. It dramatically decreased both the crossing and fluoroscopy times with maximal reduction from 201.7 +/- 111 to 36.4 +/- 13 sec, P < 0.001 and 204.7 +/- 24 to 47.2 +/- 19 sec, P < 0.001, respectively. The MNS had a 98.8% procedural success rate compared to 68% with SG techniques. Moreover it considerably limited the amount of wire usage from 5.5 to 1.3. Operators with prior MG experience performed significantly better than those without, except in the simplest phantom where the difference was nonsignificant (33.8 +/- 13 sec vs. 41.7 +/- 17 sec, P = 0.2). CONCLUSION: MNS significantly reduces both the crossing and fluoroscopy times in tortuous coronary phantom models achieving excellent success rates with dramatic reductions in guidewire usage. Operators with prior MNS experience had an advantage over the inexperienced. 相似文献
2.
Gijs A. Kleter Jan J. M. Damen Mark J. Buijs J. M. Ten Cate 《European journal of oral sciences》1997,105(3):278-284
The Maillard reaction between carbohydrate and protein has been proposed as a cause of the browning of carious lesions. The aim of the present investigation was to determine the occurrence of this reaction in bovine dentin collagen in vitro and to establish the effect of the reaction on the proteolytic degradation of bovine dentin collagen in vitro. Slices of demineralized bovine dentin were incubated with 0.2 M glucose or buffer for 10 weeks at 37°C. The formation of initial (furosine) and advanced (pentosidine) products of the Maillard reaction in dentin exposed to glucose was confirmed by HPLC. After reduction with NaBH4 to prevent intermediate Maillard products from further reaction, slices were either degraded with collagenase for fluorescence measurement or incubated with trypsin or pepsin to assess enzymatic degradation. Fluorescence characteristic for the Maillard reaction increased in glucose-exposed slices. Degradation of collagen by pepsin, but not by trypsin, was greatly depressed following glucose pretreatment. This may indicate an altered sensitivity to proteolytic degradation; the Maillard reaction thus has a potential role in caries arrestment. 相似文献
3.
Renske Oegema George McGillivray Richard Leventer Anne‐Gaëlle Le Moing Nadia Bahi‐Buisson Angela Barnicoat Simone Mandelstam David Francis Fiona Francis Grazia M. S. Mancini Sanne Savelberg Gijs van Haaften Kshitij Mankad Maarten H. Lequin 《American journal of medical genetics. Part C, Seminars in medical genetics》2019,181(4):627-637
4.
Arjan C. Lankester Gijs M. W. Van Schijndel Pauline M. L. Rood Arthur J. Verhoeven Ren A. W. Van Lier 《European journal of immunology》1994,24(11):2818-2825
The SH2 domain-containing transforming Shc protein has been implicated in mitogenic signaling via several surface receptors through p21ras. Following tyrosine phosphorylation by either receptor or non-receptor tyrosine kinases, Shc may interact with the adaptor protein Grb2, which is linked to Sos1, a guanine nucleotide exchange factor for human ras. Ligation of the antigen receptor complex on B cells (BCR) is known to activate various intracellular signaling pathways, which may accumulate in mitogenic responses. With respect to the initial steps, the activation of BCR-associated non-receptor tyrosine kinases appears to be indispensible. In this report we show that Shc proteins become tyrosine phosphorylated after BCR ligation on both transformed and normal human B cells. This is accompanied by the association of Shc with Grb2 proteins and a yet unidentified 145-kDa tyrosine phosphorylated protein. Subcellular fractionation revealed that this activation-induced multimeric Shc complex rapidly translocates towards the plasma membrane. Co-ligation of the BCR with the CD19 molecule results in a marked increase of these events, whereas CD19 cross-linking alone does not induce Shc tyrosine phosphorylation or translocation. Thus, in B cells the Shc complex may represent a molecular junction between the BCR and the mitogenic p21ras cascade. 相似文献
5.
Identification and susceptibility testing of Enterobacteriaceae and Pseudomonas aeruginosa by direct inoculation from positive BACTEC blood culture bottles into Vitek 2 总被引:2,自引:0,他引:2
下载免费PDF全文
![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Inoculation of an automated system for rapid identification (ID) and antimicrobial susceptibility testing (AST) directly from positive blood culture bottles will reduce the turnaround time of laboratory diagnosis of septicemic patients, which benefits clinical outcome and decreases patient costs. Direct test results, however, must always be confirmed by testing a pure overnight culture, which is the "gold standard." We studied the accuracy of direct testing versus repeat testing in order to investigate the possibility of refraining from repeat testing. We also assessed the clinical risk of reporting results based on direct testing only. We inoculated Vitek 2 (bioMérieux) directly from 410 positive BACTEC 9240 (BD) blood culture bottles containing gram-negative rods and studied the ID and AST results. In a comparison of direct inoculation with the standard method, a total of 344 isolates of Enterobacteriaceae and Pseudomonas aeruginosa were tested, and 93.0% were correctly identified. Of the 39 (10.2%) samples that contained bacilli not identifiable by Vitek 2, only 1 gave a conclusive, correct result. The overall MIC agreement among 312 isolates was 99.2%, with 0.8% very major and 0.02% major error rates. Of only three (polymicrobial) samples, the direct susceptibility pattern would be reported to the clinician as too sensitive. Vitek 2 results obtained from direct inoculation of blood culture bottles containing gram-negative bacilli are safe enough for immediate reporting, provided that ID and AST are consistent. Repeat testing is not necessary, unless Gram stain or overnight subculture results raise doubt about the purity of the culture. 相似文献
6.
van Noesel Carel J. M.; Lankester Arjan C.; van Schijndel Gijs M. W.; van Lier Rene A. W. 《International immunology》1993,5(7):699-705
The complement receptor 2 (CR2 or CD21) can be found in non-covalentassociation with the Blymphocyte specific CD19 complex at thesurface of mature human B cells. Upon ligation of the B cellantigen receptor complex (BCR), members of the CR2-CD19 complexmay associate with membrane immunoglobulin (mlg). Moreover,CD19 and CD21 ligands, either murine mAb, C3d fragments or Epstein—Barrvirus, are known to have profound effects on B cell activation.We here show that CD19 is tightly linked to the non-receptorsrc kinase Lyn and that the CD19 glycoprotein itself servesas a substrate for a yet undefined serine/threonine kinase presentwithin the complex. In the process of antigen recognition, mlgand the CR2-CD19 complex may bind different sites of a complement-opsonizedantigenic particle. We hypothesize that in this process, approximationto the BCR allows CD19-associated Lyn kinase to phosphorylatepotential substrates within the antigen—receptor complex,thereby effecting its coupling to the intracellular compartment. 相似文献
7.
Prins JB Bos E Huibers MJ Servaes P van der Werf SP van der Meer JW Bleijenberg G 《Psychotherapy and psychosomatics》2004,73(3):174-182
BACKGROUND: Several studies suggested that the surroundings of chronic fatigue syndrome (CFS) patients are of importance in the persistence of complaints. Contrary to what was expected, participation in support groups has not led to clinical improvement. The purpose of the present study was to describe social support in CFS patients as compared with other fatigued and non-fatigued groups. Further, changes in social support and the influence of social support on the course of CFS over a period of more than 1 year were studied in patients with and without treatment. METHODS: Baseline data were assessed in 270 CFS patients, 150 disease-free breast cancer patients, 151 fatigued employees on sick-leave and 108 healthy subjects using the Social Support List and Significant Others Scale. CFS patients were followed in cognitive behaviour therapy (CBT), guided support groups and natural course at 8 and 14 months. RESULTS: CFS patients and fatigued employees reported more negative interactions and insufficiency of supporting interactions than cancer patients and healthy controls. No differences in frequency of supporting interactions were found. Negative interactions decreased significantly after treatment with CBT, but did not change in support groups or natural course. In the natural course, higher fatigue severity at 8 months was predicted by more negative interactions at baseline. CONCLUSIONS: In CFS patients and fatigued employees, social support is worse than in disease-free cancer patients and healthy controls. Lack of social support was identified as a new factor in the model of perpetuating factors of fatigue severity and functional impairment in CFS. 相似文献
8.
W. F. van Tets M.D. J. H. C. Kuijpers M.D. Ph.D. G. Bleijenberg Ph.D. 《Diseases of the colon and rectum》1996,39(9):992-994
PURPOSE: This study was undertaken to assess biofeedback treatment (active sphincter exercises under direct electromyography vision) in neurogenic fecal incontinence. METHODS: Twelve patients with neurogenic fecal incontinence have been studied prospectively. External sphincter contractions were exercised under direct electromyographic vision twice per day for 30 minutes during 12 weeks. Manometry was done at the beginning and after 12 weeks of training to evaluate objectively changes in sphincter functions. RESULTS: No patient experienced any improvement in fecal control. Mean resting pressure increased from 7 to 9 kPa and mean squeeze pressure from 3.9 to 4.9 kPA, which was of no statistical significance (P =0.20 and P =0.46, respectively). CONCLUSIONS: External sphincter contraction exercises under direct electromyographic vision are not effective in neurogenic fecal incontinence. Degree of continence does not improve, and external sphincter function is not increased significantly. 相似文献
9.
Gijs I. T. Iordens Esther M. M. Van Lieshout Bernd C. Van Es Niels W. L. Schep Roelf S. Breederveld Peter Patka Dennis Den Hartog 《Strategies in trauma and limb reconstruction (Online)》2013,8(3):141-147
Most recent studies on procedures for stabilizing the glenohumeral joint focus on arthroscopic techniques. A relatively simple open procedure is the modified Putti-Platt procedure. The aim of these retrospective case series was to evaluate the functional outcome, patient satisfaction, and quality of life of patients who underwent this procedure. After a median follow-up time of 4.7 (P25–P75 1.7–6.8) years, fifty-one patients could be enrolled with a mean age of 25 (21–39) years. Five patients (10 %) reported re-dislocations. The median Constant score for the affected side was 84 (P25–P75 75–91). Median loss of motion in abduction, elevation, external rotation, and external rotation in 90° of abduction did not exceed 10° when compared to the healthy shoulder. A median Rowe score of 92 (P25–P75 75–95) was measured. The WOSI score and SF-36 showed excellent quality of life. The VAS proved high patient satisfaction with the outcome; 7.9 (6.8–9.5). We concluded that the modified Putti-Platt procedure leads to excellent outcome scores and only marginal restriction in range of motion combined with a high patient satisfaction. Our data prove that excellent results can be obtained with a relatively simple open procedure. 相似文献
10.
Relationship Between Objectively Assessed Physical Activity and Fatigue in Patients With Rheumatoid Arthritis: Inverse Correlation of Activity and Fatigue
下载免费PDF全文
![点击此处可从《Arthritis care & research》网站下载免费的PDF全文](/ch/ext_images/free.gif)