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   296篇
  免费   13篇
耳鼻咽喉   6篇
儿科学   3篇
妇产科学   3篇
基础医学   59篇
口腔科学   4篇
临床医学   24篇
内科学   79篇
皮肤病学   12篇
神经病学   25篇
特种医学   10篇
外科学   19篇
综合类   3篇
预防医学   13篇
眼科学   10篇
药学   7篇
肿瘤学   32篇
  2023年   1篇
  2022年   7篇
  2021年   12篇
  2020年   6篇
  2019年   7篇
  2018年   13篇
  2017年   12篇
  2016年   5篇
  2015年   8篇
  2014年   16篇
  2013年   11篇
  2012年   31篇
  2011年   23篇
  2010年   16篇
  2009年   11篇
  2008年   20篇
  2007年   18篇
  2006年   7篇
  2005年   6篇
  2004年   7篇
  2003年   4篇
  2002年   5篇
  2000年   2篇
  1999年   3篇
  1998年   3篇
  1997年   1篇
  1996年   1篇
  1992年   1篇
  1991年   2篇
  1990年   1篇
  1989年   4篇
  1988年   2篇
  1987年   1篇
  1986年   2篇
  1985年   2篇
  1984年   2篇
  1983年   1篇
  1982年   1篇
  1981年   3篇
  1980年   2篇
  1979年   6篇
  1978年   7篇
  1977年   2篇
  1976年   2篇
  1974年   5篇
  1973年   2篇
  1972年   4篇
  1970年   1篇
排序方式: 共有309条查询结果,搜索用时 15 毫秒
61.
BackgroundCurrently, evidence supports the use of adjuvant endocrine therapy with aromatase inhibitors in post-menopausal patients with hormone receptor (HR)—positive breast cancer. The goal of the current study is to understand the effect of patient age and health status on oncologists' decision to recommend adjuvant treatment (endocrine therapy and chemotherapy) in older women with HR-positive breast cancer.Patients and MethodsAn online survey was conducted, with questions related to a hypothetical patient of varying age and health status with a T2 N2 HR-positive, HER2-negative breast cancer. Treatment options included chemotherapy and endocrine therapy, endocrine therapy alone, or no therapy. Respondents (n = 151) were further asked to specify use of either tamoxifen or aromatase inhibitors. A generalized linear mixed-effects model was used to determine the effect of age and health status on recommendations.ResultsAs the hypothetical patient's age increased or health status deteriorated, oncologists (n = 151) were less likely to recommend a combination of chemotherapy and endocrine therapy (P < .0001 for both). In contrast, oncologists were more likely to recommend endocrine therapy alone with advanced age and deteriorating health status (P < .0001 for both). Oncologists were more likely to choose treatment with aromatase inhibitors as opposed to tamoxifen (P < .01), irrespective of age or health status.ConclusionWith increasing age and declining health status, oncologists were more likely to recommend endocrine therapy alone as opposed to chemotherapy with endocrine therapy. Oncologists were most likely to recommend aromatase inhibitors, irrespective of age or health status.  相似文献   
62.
OBJECTIVES: Information technology is a rapidly expanding branch of science which has affected other sciences. One example of using information technology in medicine is the Electronic Medical Records system. One medical university in Iran decided to introduce such system in its hospital. This study was designed to identify the factors which influence the quality of medical documentation when paper-based records are replaced with electronic records. METHODS: A set of 300 electronic medical records was randomly selected and evaluated against eleven checklists in terms of documentation of medical information, availability, accuracy and ease of use. To get the opinion of the care-providers on the electronic medical records system, ten physicians and ten nurses were interviewed by using of semi-structured guidelines. The results were also compared with a prior study with 300 paper-based medical records. RESULTS: The quality of documentation of the medical records was improved in areas where nurses were involved, but those parts which needed physicians' involvement were actually worse. High workloads, shortage of bedside hardware and lack of software features were prominent influential factors in the quality of documentation. The results also indicate that the retrieval of information from the electronic medical records is easier and faster, especially in emergency situations. CONCLUSIONS: The electronic medical records system can be a good substitute for the paper-based medical records system. However, according to this study, some factors such as low physician acceptance of the electronic medical record system, lack of administrative mechanisms (for instance supervision, neglecting physicians and/or nurses in the development and implementation phases and also continuous training), availability of hardware as well as lack of specific software features can negatively affect transition from a paper-based system to an electronic system.  相似文献   
63.
64.
The term breast cancer covers many different conditions, whose clinical course ranges from indolent to aggressive. However, current practice in breast cancer prevention and care, and in breast cancer epidemiology, does not take into account the heterogeneity of the disease. A comprehensive understanding of the etiology and progression of different breast cancer subtypes would enable a more patient-centered approach to breast health care: assessing an individual’s risk of getting specific subtypes of the disease, providing risk-based screening and prevention recommendations, and, for those diagnosed with the disease, tailored treatment options based on risk and timing of progression and mortality. The Athena Breast Health Network is an initiative of the five University of California medical and cancer centers to prototype this approach and to enable the development of a rapid learning system—connecting risk and outcome information from a heterogeneous patient population in real time and using new knowledge from research to continuously improve the quality of care. The Network is based on integrating clinical and research processes to create a comprehensive approach to accelerating patient-centered breast health care. Since its inception in 2009, the Network has developed a multi-site, transdisciplinary collaboration that enables the learning system. The five-campus collaboration has implemented a shared informatics platform, standardized electronic patient intake questionnaires, and common biospecimen protocols, as well as new clinical programs and multi-center research projects. The Athena Breast Health Network can serve as a model of a rapid learning system that integrates epidemiologic, behavioral, and clinical research with clinical care improvements.  相似文献   
65.

Background

Glioblastoma multiforme is the most common lethal brain tumor in human adults, with no major therapeutic breakthroughs in recent decades. Research is based mostly on human tumor cell lines deprived of their organotypic environment or inserted into immune-deficient animals required for graft survival. Here, we describe how glioblastoma specimens obtained from surgical biopsy material can be sectioned and transferred into cultures within minutes.

Methods

Slices were kept in 6-well plates, allowing direct observation, application of temozolomide, and irradiation. At the end of experiments, slice cultures were processed for histological analysis including hematoxylin-eosin staining, detection of proliferation (Ki67), apoptosis/cell death (cleaved caspase 3, propidium iodide), DNA double-strand breaks (γH2AX), and neural subpopulations. First clinical trials employed irradiation with the heavy ion carbon for the treatment of glioblastoma patients, but the biological effects and most effective dose regimens remain to be established. Therefore, we developed an approach to expose glioblastoma slice cultures to 12C and X-rays.

Results

We found preservation of the individual histopathology over at least 16 days. Treatments resulted in activation of caspase 3, inhibition of proliferation, and cell loss. Irradiation induced γH2AX. In line with clinical observations, individual tumors differed significantly in their susceptibility to temozolomide (0.4%–2.5% apoptosis and 1%–15% cell loss).

Conclusion

Glioblastoma multiforme slice cultures provide a unique tool to explore susceptibility of individual tumors for specific therapies including heavy ions, thus potentially allowing more personalized treatments plus exploration of mechanisms of (and strategies to overcome) tumor resistance.  相似文献   
66.
67.
Resection of the petrous temporal bone to various degrees provides different levels of access to lesions of the posterior fossa. However, regarding the numerous variations, precise distances of petrosal bone are not still clearly described. This may lead to serious complications during transpetrosal surgeries. Our objective was to evaluate different distances of temporal bone landmarks in order to assess their variations and the possible correlations between them. This anatomical study was performed on 60 temporal bones from 60 human cadavers in the years 2006 and 2007. All the bones contained an adequate portion of the petrous apex and attached fossa dura. Twelve landmarks were defined and 27 different distances were measured for each temporal bone using two-point caliper. Less variation was observed in the superoinferior diameter of horizontal carotid canal with the less coefficient of variation (CV) of 9.29; whereas, the most variation was detected in the inferior (axial) plane of posterior semicircular canal to superior plane of jugular bulb (CV = 57.65). There was a significant correlation between vertical intratemporal diameter of carotid in pyramidal direction, and superior–inferior diameter of horizontal carotid canal (r Pearson = 0.500, P < 0.001). Other significant correlations were also found between other distances. The variations of different distances and landmarks were evaluated and many significant correlations were demonstrated between them which could potentially aid ENT specialists and neurosurgeons in order to approach anatomical landmarks and cranial fossas more safely during otologic and neurotologic surgeries. It could also help the design of middle ear prosthesis.  相似文献   
68.
69.

OBJECTIVE

To determine if baseline subgroups in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial can be identified for whom intensive compared with standard glycemia treatment had different effects on all-cause mortality.

RESEARCH DESIGN AND METHODS

Exploratory post hoc intention-to-treat comparisons were made between intensive and standard glycemia groups on all-cause mortality by subgroups defined by baseline characteristics.

RESULTS

There were few significant interactions between baseline characteristics and effects of intensive versus standard glycemia treatment on mortality: self-reported history of neuropathy (hazard ratio [HR] 1.95, 95% CI 1.41–2.69) versus no history of neuropathy (0.99, 0.79–1.26; P value for interaction 0.0008), higher A1C (A1C >8.5%: HR 1.64, 95% CI 1.22–2.22; A1C 7.5–8.4%: 1.00, 0.75–1.34; A1C <7.5%: 1.00, 0.67–1.50; P value for interaction 0.04), and aspirin use (HR 1.45, 95% CI 1.13–1.85, compared with 0.96, 0.72–1.27, in nonusers; P value for interaction 0.03).

CONCLUSIONS

We found a remarkable similarity of effect from intensive compared with standard glycemia treatment on mortality across most baseline subgroups. No differential effect was found in subgroups defined by variables anticipated to have an interaction: age, duration of diabetes, and previous history of cardiovascular disease. The three baseline characteristics that defined subgroups for which there was a differential effect on mortality may help identify patients with type 2 diabetes at higher risk of mortality from intensive regimens for glycemic control. Further research is warranted.Numerous epidemiological studies have demonstrated a relationship between elevated A1C and a greater risk of cardiovascular (CVD) events and mortality in type 2 diabetes (13). Therefore, it has been hypothesized that a reduction to near-normal levels of A1C in patients with type 2 diabetes would reduce the risk of these adverse outcomes. Three large randomized controlled clinical trials testing this hypothesis in individuals with longstanding type 2 diabetes reported their main results in the past 2 years (46).The Data Safety Monitoring Board of the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial discontinued the intensive glycemia arm because of an increase in all-cause mortality in the intensive glycemia arm compared with the standard glycemia arm. The finding of excess mortality in the intensive arm of the ACCORD trial has led to controversy about implementation of intensive glucose control in patients with type 2 diabetes (7,8). Adding to the controversy were results of the Action in Diabetes and Vascular Disease: Preterax and Diamicron MR Controlled Evaluation (ADVANCE) and Veterans Affairs Diabetes Trial (VADT), demonstrating that although there was no significant reduction in the primary end point of CVD events, there was no increase in mortality with the intensive glycemia arm compared with the standard glycemia arm (4,6), which has raised questions about reasons for these discrepancies (912).A critical question relates to the applicability and generalizability of the conclusions of the ACCORD trial to the broader population or to specific subgroups of patients with type 2 diabetes. Indeed, prespecified subgroup analyses in ACCORD did suggest a significant benefit of intensive glycemic control on CVD events in those participants with lower A1C at entry or absence of CVD event by history, but there was no suggestion of a differential effect on mortality (5). However, these observations are based on only a few subgroup analyses at the time of the primary publication. The effect on mortality of intensive compared with standard glycemia treatment may have been modified by other possible characteristics of patients at entry. We have therefore carried out exploratory post hoc analyses of the effects of intensive compared with standard glycemia treatment in ACCORD participants categorized by various baseline characteristics on all-cause mortality at the time of discontinuation of the intensive glycemia treatment of ACCORD, with the goal to determine if particular subgroups at higher or lower risk from the intensive intervention can be identified.  相似文献   
70.
Twenty-four magnetic resonance (MR) imaging–guided percutaneous adrenal biopsies performed between April 2009 and October 2016 were reviewed retrospectively. Epidemiologic, procedural, and histopathologic data were retrospectively collected. Mean size of tumors was 4.3 cm (range, 1.5–16.0 cm). Mean procedure time was 49 min (range, 24–95 min). Mean needle angulation was 27.7° (range, 0°–60°). Mean depth was 9.6 cm (range, 5.8–13.7 cm). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of MR imaging–guided biopsy were 95.5%, 100%, 100%, 66.7%, and 95.8%, respectively. There were no immediate or delayed complications. MR imaging guidance seems safe and accurate to target adrenal-gland masses.  相似文献   
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