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81.
82.
该文旨在对小唾液腺癌的治疗进行回顾。小唾液腺癌可发生在头颈部很多位置,通常表现为黏膜下肿块。影像学检查是对肿瘤发病部位及病变范围内解剖结构的关系进行评估的基础。切取活检或穿吸活检可以决定肿瘤的病理类型和分级。随着分子生物学技术的不断进步,小唾液腺癌的诊断  相似文献   
83.

Background

Factors influencing survival in children with HCC have not been studied. The objective of this study was to identify prognostic factors in pediatric HCC, and to determine whether regional lymphadenectomy is associated with improved survival.

Methods

We performed a retrospective cohort study using the Surveillance, Epidemiology and End Results (SEER) registry. All patients < 20 years old diagnosed with HCC from 1973–2009 were included. Disease-specific survival was compared using Kaplan-Meier statistics and Cox proportional-hazards regression.

Results

We identified 238 patients (139 Male: 99 Female). Overall, 112 (47%) received an operation (resection/transplantation). Observed mortality and adjusted hazard of disease-specific death was greater for females (HR = 2.07, p = 0.013) and older children. Among operative patients, 44% were documented to have a regional lymphadenectomy. Although demographic factors did not differ between lymphadenectomy and non-lymphadenectomy groups, patients who underwent lymphadenectomy had a greater proportion of metastatic disease (24% vs. 15%) and fibrolamellar HCC (53% vs. 31%). Five-year survival for lymphadenectomy patients was superior to non-lymphadenectomy (70% vs. 57%). Adjusted mortality for lymphadenectomy was also improved relative to non-lymphadenectomy (HR = 0.26, p = 0.013).

Conclusions

HCC in children is associated with poor survival, especially among children older than 4 years and girls. In surgical candidates, regional lymphadenectomy may be associated with improved survival.  相似文献   
84.

Background

Several strategies for the treatment of pathologic proximal femur fractures are practiced but treatment outcomes have not been rigorously compared.

Questions/purposes

Major variations in the use of intramedullary fixation, extramedullary/plate-screw fixation, and endoprosthetic reconstruction techniques for pathologic proximal femur fractures in patients with skeletal metastases are reported. The clinical and surgical variables that influence this choice differ among treating surgeons. To characterize the technique preferences and to identify areas of consensus regarding specific clinical presentations, we administered an online survey to the Musculoskeletal Tumor Society (MSTS) membership. We also tested whether responses correlated with the respondents’ years in practice and asked about the indications for wide tumor resection and the role of tumor debulking and adjuvant cementation.

Methods

A 10-minute, web-based survey was sent via email to 244 MSTS members. The survey queried participants’ musculoskeletal oncology training and experience and presented case scenarios illustrating different combinations of four variables that influence decision-making: cancer type, estimated patient survival, fracture displacement, and anatomic region of involvement.

Results

Forty-one percent (n = 98) of MSTS members completed the survey. Intramedullary nail fixation (IMN; 45%) and proximal femur resection and reconstruction (34%) were the most commonly recommended techniques followed by long-stem cemented hemiarthroplasty/cemented hemiarthroplasty (15%) and open reduction and internal fixation (7%). Most respondents (56%) recommended use of cementation with IMN. Differences of opinion on recommended treatment were associated with variations in cancer type, fracture displacement, and anatomic region of involvement.

Conclusions

Our online survey showed a trend among MSTS members for selecting IMN and arthroplasty-related techniques to treat pathologic fractures of the proximal femur, but major differences in preferred operative technique exist. Prospective studies are needed to develop consistent, evidence-based treatment recommendations.  相似文献   
85.
There are more than 200,000 Canadians living with permanent pacemakers or implantable defibrillators, many of whom will require surgery or invasive procedures each year. They face potential hazards when undergoing surgery; however, with appropriate planning and education of operating room personnel, adverse device-related outcomes should be rare. This joint position statement from the Canadian Cardiovascular Society (CCS) and the Canadian Anesthesiologists' Society (CAS) has been developed as an accessible reference for physicians and surgeons, providing an overview of the key issues for the preoperative, intraoperative, and postoperative care of these patients. The document summarizes the limited published literature in this field, but for most issues, relies heavily on the experience of the cardiologists and anesthesiologists who contributed to this work. This position statement outlines how to obtain information about an individual's type of pacemaker or implantable defibrillator and its programming. It also stresses the importance of determining if a patient is highly pacemaker-dependent and proposes a simple approach for nonelective evaluation of dependency. Although the document provides a comprehensive list of the intraoperative issues facing these patients, there is a focus on electromagnetic interference resulting from electrocautery and practical guidance is given regarding the characteristics of surgery, electrocautery, pacemakers, and defibrillators which are most likely to lead to interference. The document stresses the importance of preoperative consultation and planning to minimize complications. It reviews the relative merits of intraoperative magnet use vs reprogramming of devices and gives examples of situations where one or the other approach is preferable.  相似文献   
86.

Background

Pulmonary vein isolation (PVI) forms the basis of catheter ablation strategies for atrial fibrillation (AF). Ablation of additional sites has been used to increase the efficacy of ablation procedures in restoring and maintaining normal sinus rhythm.

Objective

The aim of this paper was to compare the effectiveness of PVI versus PVI plus adjuvant atrial ablations (PVI+) in patients with AF.

Methods

A systematic search using bibliographic databases and gray literature was undertaken. Randomized and non-randomized controlled trials evaluating clinical efficacy, effectiveness, or safety of ablation procedures in adults with AF were included in this review.

Results

Of 3,204 potential citations identified by the original search, 21 randomized controlled trials and three non-randomized trials were included. Meta-analysis results reveal that in the first year after ablation, AF patients who underwent PVI+ strategies had a significantly higher rate of maintaining sinus rhythm than those who underwent PVI alone (RR 1.10, 95?% CI 1.02, 1.17). However, a subgroup meta-analysis was statistically significant for only PVI+ left atrial (LA) linear ablations (RR 1.16, 95?% CI 1.04, 1.29). The pooled success rates were higher in PVI+ group for both paroxysmal (RR 1.14, 95?% CI 1.06, 1.24) and non-paroxysmal AF (RR 1.53, 95?% CI 1.10, 2.14).

Conclusion

PVI+ strategies, particularly PVI+ LA ablations, appear to result in higher success rates than PVI alone in the first year after the procedure. Studies of longer duration are needed to evaluate the long-term benefits and safety of different adjunctive ablation approaches for rhythm control in AF patients.  相似文献   
87.
88.

Purpose

To conduct a systematic literature review of the reliability, construct validity, and responsiveness of the SF-36® Health Survey (SF-36) in patients with ulcerative colitis (UC).

Methods

We performed a systematic search of electronic medical databases to identify published peer-reviewed studies which reported scores from the eight scales and/or two summary measures of the SF-36 collected from adult patients with UC. Study findings relevant to reliability, construct validity, and responsiveness were reviewed.

Results

Data were extracted and summarized from 43 articles meeting inclusion criteria. Convergent validity was supported by findings that 83% (197/236) of correlations between SF-36 scales and measures of disease symptoms, disease activity, and functioning exceeded the prespecified threshold (r ≥ |0.40|). Known-groups validity was supported by findings of clinically meaningful differences in SF-36 scores between subgroups of patients when classified by disease activity (i.e., active versus inactive), symptom status, and comorbidity status. Responsiveness was supported by findings of clinically meaningful changes in SF-36 scores following treatment in non-comparative trials, and by meaningfully larger improvements in SF-36 scores in treatment arms relative to controls in randomized controlled trials. The sole study of SF-36 reliability found evidence supporting internal consistency (Cronbach’s α ≥ 0.70) for all SF-36 scales and test–retest reliability (intraclass correlation coefficient ≥0.70) for six of eight scales.

Conclusions

Evidence from this systematic literature review indicates that the SF-36 is reliable, valid, and responsive when used with UC patients, supporting the inclusion of the SF-36 as an endpoint in clinical trials for this patient population.
  相似文献   
89.
Evidence from animal and human studies suggests that ocular growth is influenced by visual experience. Reduced retinal image quality and imposed optical defocus result in predictable changes in axial eye growth. Higher order aberrations are optical imperfections of the eye that alter retinal image quality despite optimal correction of spherical defocus and astigmatism. Since higher order aberrations reduce retinal image quality and produce variations in optical vergence across the entrance pupil of the eye, they may provide optical signals that contribute to the regulation and modulation of eye growth and refractive error development. The magnitude and type of higher order aberrations vary with age, refractive error, and during near work and accommodation. Furthermore, distinctive changes in higher order aberrations occur with various myopia control treatments, including atropine, near addition spectacle lenses, orthokeratology and soft multifocal and dual-focus contact lenses. Several plausible mechanisms have been proposed by which higher order aberrations may influence axial eye growth, the development of refractive error, and the treatment effect of myopia control interventions. Future studies of higher order aberrations, particularly during childhood, accommodation, and treatment with myopia control interventions are required to further our understanding of their potential role in refractive error development and eye growth.  相似文献   
90.
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