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   1185篇
  免费   106篇
  国内免费   27篇
耳鼻咽喉   12篇
儿科学   51篇
妇产科学   17篇
基础医学   156篇
口腔科学   30篇
临床医学   117篇
内科学   375篇
皮肤病学   18篇
神经病学   37篇
特种医学   124篇
外科学   123篇
综合类   13篇
预防医学   54篇
眼科学   10篇
药学   126篇
中国医学   3篇
肿瘤学   52篇
  2021年   10篇
  2020年   7篇
  2019年   12篇
  2018年   20篇
  2017年   8篇
  2016年   14篇
  2015年   18篇
  2014年   19篇
  2013年   31篇
  2012年   43篇
  2011年   36篇
  2010年   27篇
  2009年   33篇
  2008年   54篇
  2007年   56篇
  2006年   44篇
  2005年   44篇
  2004年   30篇
  2003年   43篇
  2002年   31篇
  2001年   31篇
  2000年   27篇
  1999年   29篇
  1998年   46篇
  1997年   47篇
  1996年   58篇
  1995年   46篇
  1994年   40篇
  1993年   38篇
  1992年   24篇
  1991年   27篇
  1990年   24篇
  1989年   31篇
  1988年   23篇
  1987年   18篇
  1986年   23篇
  1985年   19篇
  1984年   21篇
  1983年   16篇
  1982年   11篇
  1981年   12篇
  1980年   12篇
  1979年   9篇
  1978年   7篇
  1977年   11篇
  1976年   12篇
  1975年   13篇
  1974年   9篇
  1968年   8篇
  1966年   8篇
排序方式: 共有1318条查询结果,搜索用时 15 毫秒
61.
62.
A patient with progressive osteolysis of the carpal and tarsal bones with glomerulonephritis of unusual severity is described. There was a notable absence of osteodystrophy in this and other reported cases who had chronic renal failure.  相似文献   
63.
Surgery remains the treatment of choice for massive and recurrent hemoptysis. In some instances, however, immediate surgical intervention is contraindicated. In these situations, bronchial artery embolization (BAE) has proved to be a successful definitive treatment for non-surgical candidates and a palliative therapy in patients requiring hemodynamic stabilization prior to surgery. The most serious complication of BAE is spinal cord ischemia. This relates directly to the potential anastomotic connections between the bronchial circulation and the anterior spinal artery. Somatosensory evoked potentials (SSEPs) have been used in the past to monitor spinal cord ischemia during procedures that threaten the vascularity of the spinal cord. The authors report two cases in which SSEPs were employed to monitor spinal cord ischemia during bronchial artery embolization.  相似文献   
64.

Context

The purpose of this report is to review immunotherapies under investigation for patients with renal cell carcinoma (RCC), the most common form of kidney cancer, for which the incidence and mortality rate continue to increase.

Objective

To summarize and evaluate current data on immunotherapies for RCC and discuss issues to be resolved before integration into the RCC treatment paradigm.

Evidence acquisition

A search of Medline, clinicaltrials.gov, and congress abstracts/treatment guidelines was performed in May 2012 using the following terms (and variations): metastatic renal cell carcinoma, practice guidelines, response/resistance to current treatments, immunotherapy, novel immunotherapeutic strategies, T-cell modulation, immune priming, innate immunity, and combination therapy.

Evidence synthesis

Prior to the advent of novel agents targeting the vascular endothelial growth factor and mechanistic target of rapamycin pathways, interleukin-2 (IL-2) and interferon-α were the mainstays of RCC treatment. IL-2 remains one of the only treatments capable of curing advanced RCC, albeit in few patients. Despite recent advances, unmet need still exists for patients in the adjuvant setting, those with poor prognostic factors, and those who have progressed on prior targeted therapies. Improved understanding of host–tumor immune interactions has led to development of novel immunotherapeutic agents, including antibodies against immune checkpoint proteins (eg, programmed death-1 and cytotoxic T-lymphocyte antigen-4), and various vaccines. Because many of these compounds are in development, clinical experience with them is limited, although some have demonstrated activity in preliminary studies.

Conclusions

It is not yet clear where these new immunotherapies will fit into RCC treatment paradigms, but they may provide new options for patients whose current choices are limited. Furthermore, predictive biomarkers are needed to identify patients who will derive the greatest benefit from immunotherapy.  相似文献   
65.

Purpose

To report the outcomes of 47 patients with temporal bone osteoradionecrosis treated primarily with surgical resection in order to analyze whether flap type and hyperbaric oxygen use affect wound breakdown.

Materials and methods

Between January 1998 and January 2016, 47 patients were treated for temporal bone osteoradionecrosis with surgery. Some patients were also treated with hyperbaric oxygen. Resection of grossly necrotic temporal bone was followed by immediate reconstruction with local, regional, or free flaps. Minimum follow-up was 6 months. If patients had breakdown of their initial reconstructions, secondary reconstruction was performed with either a regional or free flap. During the post-operative period, wound breakdown, flap complications, and patient survival were noted.

Results

30 patients developed ORN from primary radiotherapy while 17 had post-operative radiation. It was found that wound breakdown was significantly associated with type of flap reconstruction (p = 0.02) with local flap reconstruction portending a poorer prognosis. Hyperbaric oxygen was not associated with decreased wound breakdown (p = 0.5).

Conclusions

Surgical treatment can be an effective treatment for temporal bone osteoradionecrosis, without hyperbaric oxygen providing any additional benefit. Reconstruction with regional or free flaps may be a more reliable method to resurface defects compared to local flaps.  相似文献   
66.
An adapted tensile stress methodology for the fracture of microcrystalline cellulose (MCC) tablets has been investigated and implemented. The application of the generally applied linear elastic fracture mechanic (LEFM) parameters used to describe the fracture behaviour of these porous systems has been discussed. The application of an effective crack length concept, comprising of the notch depth and a process zone length designated delta c, has enabled the localised non-linear response of the MCC tablets to be characterised in a quantified manner. The requirement of the composite value delta c is postulated to be a direct result of the internal properties of the tablet formed during the compaction process due to its strong dependence on porosity. The high compact relative density creates a greater possibility for both local small-scale plastic yielding at the crack tip, commonly found in polymer materials and microcracking ahead of the crack tip, typically observed in the fracture of ceramics. The extrapolated value of KIC0 of 0.72 MPa m0.5 found in this work lies within the range found in literature for this material indicating that the adopted procedure is acceptable for the determination of the resistance to fracture of MCC compacts.  相似文献   
67.
Thirty-five empirical studies from 25 peer-reviewed journals and one book chapter were analyzed through a content analysis for trends in publication, methodological, and research foci in telesupervision between 1990 and 2016. The most significant increase in publications occurred in the past decade. Methodological trends revealed that video-conferencing, webcam, and cybersupervision were frequent terminologies used to describe telesupervision. Studies were focused on supervisee experiences, used an individual supervision method, a videoconferencing medium of supervision delivery, and a qualitative methodology with both male-female samples. Studies examined three topics: effectiveness of telesupervision, counselor development, and supervisory relationship. Implications and future research directions are discussed.  相似文献   
68.
69.
OBJECTIVE: The purpose of this study was to assess the clinical and economic impact of the introduction of inhaled corticosteroid therapy for asthma in a cohort of children 12 years and younger who were North Carolina Medicaid enrollees.
METHODS: The North Carolina Medicaid claims database was used to retrieve clinical and economic variables for the purpose of this study. The case group, which was comprised of 84 children who started corticosteroid inhaler therapy between March 1994 and March 1995, was followed up for 1 year before and 1 year after the start of the therapy. The control group was comprised of 72 children with similar severity of asthma who remained on any other therapy other than corticosteroids for a continuous 2-year period. Paired t-tests were used to compare differences, and multiple regression analysis was used to adjust for potential confounders.
RESULTS: There was a 58% reduction in hospital visits, and a 19% reduction in physician visits in the case group after initiation of inhaled corticosteroids. In the control group, an increase of 34% in the number of outpatient visits occurred in the second year. All the decreases and increases were statistically significant. Children with regular patterns of inhaled corticosteroid refills were found to be significantly lower costing for Medicaid. However, after adjusting for potential confounders, no significant change in health care costs per asthmatic child occurred as a result of the introduction of inhaled corticosteroid therapy.
CONCLUSION: Overall, the study found that introduction of inhaled corticosteroids in a cohort of asthmatic children enrolled in Medicaid was beneficial to Medicaid because it brought about dramatic decreases in health care utilization without additionally increasing costs.  相似文献   
70.
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