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31.
The most common method of treating the arthrotic distal radioulnar joint (DRUJ) is resection of the entire ulnar head (Darrach procedure). Complications related to instability of the distal forearm resulting from loss of the ulnar head are usually manifested by pain and weak grip strength and have remained the drawbacks of this procedure. In an attempt to mechanically stabilize the distal forearm, an endoprosthesis was developed to replace the ulnar head after Darrach resection. The purpose of this study was to: 1) evaluate the dynamic effects of the Darrach procedure on radioulnar convergence; and 2) evaluate the mechanical efficacy of two soft tissue stabilizing techniques (Pronator quadratus advancement flap and ECU/FCU tenodesis) for the unstable distal ulnar stump and 3) the stability after the implantation of an ulnar head endoprosthesis following a Darrach resection on radioulnar convergence. With a dynamic PC-controled forearm simulator the rotation of 7 fresh-frozen cadaver upper extremities was actively and passively performed while loading relevant muscles. Resultant total forearm torque and the 3-dimensional kinematics of the ulna, radius and third metacarpal were recorded simultaneously. The implantation of the ulnar head endoprosthesis effectively restored the stability of the DRUJ. There were significantly better results after the implantation of the prosthesis compared with the Darrach and the soft tissue stabilization procedures. This study provides laboratory validity to the option of implanting an ulnar head endoprosthesis as an attempt to stabilize the distal forearm after Darrach resection in lieu of performing soft tissue stabilization techniques.  相似文献   
32.
The hypothenar hammer syndrome (HHS) is a rare form of secondary Raynaud's phenomenon in workers who frequently use the ulnar side of the palm as a hammer. Clinically the patient with HHS shows neurologic symptoms such as paresthesia, numbness and pain and signs of vascular insufficiency such as coldness, pallor, discoloration and blanching of the affected ulnar sided fingers. The diagnosis is verified by angiography, showing thrombosis or aneurysm of the distal ulnar artery.We report on the treatment and outcome of 5 patients with HHS. All patients were painfree after treatment. But with the ongoing working habit of using the hand as a hammer there is always the risk of a recurrence. Therefore the job environment has to be changed considerably and the most effort should go into prevention and prophylaxis. If the change of the working habit is not possible, the job is clearly at stake.  相似文献   
33.
BACKGROUND AND AIMS OF THE STUDY: Extended experiences of the Carpentier-Edwards Supra-Annular Valve (CE-SAV) and the Hancock II (H II) porcine bioprostheses were evaluated to determine the freedom from structural valve deterioration (SVD) by reoperation in the aortic position. METHODS: Between 1981 and 1994, 1,524 procedures (mean patient age 67.6+/-11.2 years) with the CE-SAV, and 670 procedures (mean patient age 65.2+/-12.1 years) with the H II were conducted at the University of British Columbia and University of Toronto, respectively. The patient populations were differentiated by mean age, gender and valve size, but not by concomitant coronary artery bypass. The analyses included actuarial and actual freedom from SVD and evaluation of predictors of SVD. RESULTS: Actuarial freedom from SVD at 15 years for patients aged > or =65 years was 91.5+/-2.9% for CE-SAV, and 100% for H II (p = NS), while the actual freedom was 96.4+/-1.0% and 100%, respectively. For the patient population aged 66-70 years, the actuarial freedom from SVD was 87.0+/-6.0% for CE-SAV and 100% for H II (p = NS), while the actual rates were 93.6+/-2.3% and 100%, respectively. For the population aged >70 years, the actuarial freedom from SVD was 96.9+/-1.5% for CE-SAV, and 100% for H II (p = NS), while the actual freedom was 98.8+/-0.5% and 100%, respectively. In the patient population aged <65 years, the actuarial freedom from SVD at 15 years favored the H II (p = 0.04), and the actual freedom showed the same outcome. The valve type was not predictive of SVD for age groups < or =60 years, >60 years, 61-70 years and >70 years, but was predictive for the overall population (p = 0.03), as was age and previous valve replacement. CONCLUSION: The CE-SAV and Hancock II both provide satisfactory clinical performances, with a low incidence of SVD, and no significant difference in SVD was shown in patients aged > or =65, 66-70, or >70 years. There is a trend to less SVD by actual analysis for the Hancock II in patients aged <65 years. This evaluation must be considered as work-in-progress because of the limited number of patients at risk at 15 years, especially with the Hancock II prosthesis.  相似文献   
34.
Summary We determined the nucleotide sequence of the SH gene and its flanking regions over a range of 380 nucleotides for three distinct mumps virus (MUV) isolates. Two isolates from the 1992 mumps epidemic in Western Switzerland and one MUV isolated in 1995 in the same geographic area have been analyzed and compared to 16 recently published SH nucleotide sequences and their presumed amino acid sequences. The nucleotide sequences from the 1992 MUV isolates were identical and closely related to two MUV strains from Eastern Switzerland and strains from the U.K. The MUV isolated in 1995 is clearly different from all other strains.  相似文献   
35.
A report on first findings of quantitative investigations of beta activity in the frequency domain is presented. Spectral analysis techniques were applied in three parallel still ongoing clinical studies, i.e. (1) an exploration of beta activities in a broad clinical material, (2) a study of the possible use of quantitative beta assessment in antiepileptic drug therapy, and (3) an investigation of special patterns with harmonic components in the beta band. Several clearly distinguishable types of spectral shapes, different coherence characteristics, significant alterations by changes of drug composition and a rich variation of harmonic patterns indicate a large and fascinating new field for clinical EEG research.  相似文献   
36.
Surgical treatment of idiopathic postmenopausal osteoarthrosis of the trapeziometacarpal joint with the Epping resection arthroplasty was performed in 57 cases in 49 women. Data show good pain relief (between 58% and 76%), very good subjective results with 89% patient satisfaction and Disability of Arm, Shoulder, Hand (DASH) scores in the lower third of the scale after 35 months' follow-up. Good functional results with respect to radial abduction (51 degrees) and palmar flexion (45 degrees), as well as improvement in strength measurements, could be achieved. Some patients (13%) reported remaining problems with occasional pain during performance of activities of daily life and work. A significant proximal metacarpal migration (31%) without correlation to objective or subjective outcome was found.The Epping procedure has proven to be a valuable alternative procedure to treat idiopathic postmenopausal trapeziometacarpal arthrosis after a midterm follow-up period. Still, careful patient selection is important and sufficient preoperative information necessary.  相似文献   
37.
The pathology of chronic dermal ulcers is characterized by excessive proteolytic activity which degrades extracellular matrix. The transforming growth factor-beta (TGF-beta) has been identified as an important component of wound healing. Recent developments in molecular therapy offer exciting prospects for the modulation of wound healing, specifically those targeting TGF-beta. We investigated the effect of TGF-beta antisense oligonucleotides on the mRNA expression of matrix metalloproteinases in cultured human keratinocytes, fibroblasts and endothelial cells using multiplex RT-PCR. The treatment of keratinocytes and fibroblasts with TGF-beta antisense oligonucleotides resulted in a significant decrease of expression of mRNA of MMP-1 and MMP-9 compared to controls. Accordingly, a decreased expression of MMP-1 mRNA in endothelial cells was detectable. Other MMPs were not affected. Affecting all dermal wound-healing-related cell types, TGF-beta antisense oligonucleotide technology may be a potential therapeutic option for the inhibition of proteolytic tissue destruction in chronic wounds. Pharmaceutical intervention in this area ultimately may help clinicians to proactively intervene in an effort to prevent normal wounds from becoming chronic.  相似文献   
38.
Periprosthetic capsular contracture is a common problem associated with implant-based breast reconstruction. The purpose of this study was to determine if bacterial colonization of the tissue expander contributes to contracture of the permanent implant. Medical records were reviewed for 86 patients (124 tissue expanders) between 1997 and 2001 in 1 institution. Three specimens taken from the expander were cultured. The overall incidence of colonization was 42.7%; 49.4% (38.8-60.0) of immediate and 28.2% (14.1-42.3) of delayed expanders had at least 1 positive culture site (P = 0.043). The most common organisms were Propionibacterium acnes (57.6%), Staphylococcus epidermidis (31.0%), and Peptostreptococcus (5.8%). Statistical analysis revealed no significant difference between colonization of the expander and capsular contracture of the permanent prosthesis (P = 0.59). 45.8% (25.9-65.8) of breasts irradiated preoperatively developed contracture versus 14% (7.2-20.8) with no irradiation (P = 0.0013). These results suggest that colonization of the expander occurs frequently, irradiation predisposes to contracture, and colonization did not contribute to secondary implant contracture in this study population.  相似文献   
39.
The present study describes the concepts of arteriovenous (A-V) loupes prior to microsurgical free flap transfer in a selected high-risk group of patients. A one-stage concept was employed in 26 patients; 5 patients underwent two-stage flap transfer. Seven thrombotic occlusions of the A-V fistula or flap vessels were recorded; 6 patients underwent successful revision. Overall flap survival was 96.8% and compared favorably to reports in the literature. Defect coverage could be achieved in all but one case. It can be concluded from the data that in selected high-risk patient groups, i.e., following radiation, compound trauma, chronic infection, or multiple comorbidities, the creation of an A-V fistula prior to flap transfer may facilitate innovative reconstructive solutions.  相似文献   
40.
PURPOSE: To evaluate if information campaigns and introduction of information leaflets lead to an improvement in patient satisfaction with anesthesia care. METHODS: In 2000, we carried out an assessment of patient satisfaction with anesthesia care. "Information/involvement in decision making" was identified as the worst problem area. The three hospitals involved in this study introduced strategies to improve this dimension of patient satisfaction by launching information campaigns, producing or improving information brochures (particularly in hospitals A and C), and by expanding the preanesthetic care unit (hospital B). In 2002, a second survey was carried out. Each of the hospitals sent questionnaires to 600 elective surgery patients after discharge. We compared the total problem scores (the percentage of patients who responded that a problem was present) and the problem scores for the dimension 'information/involvement in decision making' between 2000 and 2002. RESULTS: The total problem score (mean in %, 95% confidence interval) for all three hospitals together remained unchanged [19% (1)], as well as the problem scores for each hospital [hospital A 16% (1), hospital B 21% (1), hospital C 20% (1)]. The problem score for 'information/involvement in decision making' remained unchanged also: 31% (29-33) in 2000 compared to 28% (26-30) in 2002. CONCLUSION: Information campaigns and the introduction of information leaflets alone do not improve patient satisfaction with anesthesia care.  相似文献   
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