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   2912篇
  免费   201篇
  国内免费   17篇
耳鼻咽喉   32篇
儿科学   85篇
妇产科学   85篇
基础医学   298篇
口腔科学   75篇
临床医学   264篇
内科学   605篇
皮肤病学   86篇
神经病学   165篇
特种医学   73篇
外国民族医学   1篇
外科学   650篇
综合类   85篇
一般理论   4篇
预防医学   150篇
眼科学   99篇
药学   200篇
中国医学   23篇
肿瘤学   150篇
  2024年   4篇
  2023年   48篇
  2022年   84篇
  2021年   146篇
  2020年   89篇
  2019年   127篇
  2018年   154篇
  2017年   101篇
  2016年   101篇
  2015年   79篇
  2014年   130篇
  2013年   137篇
  2012年   242篇
  2011年   209篇
  2010年   121篇
  2009年   99篇
  2008年   138篇
  2007年   140篇
  2006年   143篇
  2005年   131篇
  2004年   92篇
  2003年   95篇
  2002年   81篇
  2001年   56篇
  2000年   56篇
  1999年   47篇
  1998年   17篇
  1997年   14篇
  1996年   9篇
  1995年   13篇
  1994年   6篇
  1993年   7篇
  1992年   24篇
  1991年   21篇
  1990年   26篇
  1989年   14篇
  1988年   15篇
  1987年   9篇
  1986年   15篇
  1985年   7篇
  1983年   4篇
  1980年   5篇
  1979年   10篇
  1978年   8篇
  1976年   5篇
  1975年   4篇
  1970年   4篇
  1969年   6篇
  1967年   4篇
  1966年   5篇
排序方式: 共有3130条查询结果,搜索用时 15 毫秒
31.
32.
Background and purposeThe incidence of retrosternal goiter (RSG) varies from 2% to 26% of all thyroidectomies, depending on the defining criteria. There are no clear guidelines to identify patients that require an intrathoracic approach. So, we tried to correlate, between the size and/or anatomical site of the RSG based on preoperative CT findings and the surgical approaches used, aiming at defining those patients with RSG who are in need for thoracic approach.Patients and methodsOut of 1481 patients underwent thyroidectomy at the National Cancer Institute (NCI), Cairo University, between January 2000 and December 2009, only 73 (4.93%) of them had retrosternal extension. Demographic, clinical, operative, anatomical, and pathological data of patients with RSG were recorded and analyzed.ResultsThe intraoperative extension of the goiter correlated with the extension seen in the CT in all except two patients. Laterality and longitudinal extension found in preoperative CT, correlated well with the surgical findings. The approach used was cervical in 66 cases (90.4%); combined approach in six patients (8.2%). Pure thoracic (full sternotomy) was used alone in one case (1.4%). Extension of the RSG down to or below the arch was associated with an increased risk of using a thoracic approach p < 0.0001.ConclusionPreoperative CT, can be used effectively to guide the indications for using a thoracic approach. Reaching the aortic arch or beyond and loss of fat planes in CT, recurrent and malignant disease, are significant risk factors for using a thoracic approach.  相似文献   
33.
Thyroid hormone (TH) receptors are present in the myocardium and vascular tissue, and minor alterations in TH concentration can affect cardiovascular (CV) physiology. The potential mechanisms that link CV disease with thyroid dysfunction are endothelial dysfunction, changes in blood pressure, myocardial systolic and diastolic dysfunction, and dyslipidemia. In addition, cardiac disease itself may lead to alterations in TH concentrations (notably, low triiodothyronine syndrome) that are associated with higher morbidity and mortality. Experimental data and small clinical trials have suggested a beneficial role of TH in ameliorating CV disease. The aim of this review is to provide clinicians dealing with CV conditions with an overview of the current knowledge of TH perturbations in CV disease.  相似文献   
34.
A 52 year old male presented with peripheral ulcerative keratitis in the right eye. Patient’s history included retinitis pigmentosa, pseudophakia (right eye), cataract (left eye), bilateral partial deafness, ischemic heart disease, hypertension, type 1 diabetes mellitus, depression, hyperparathyroidism, hypertriglycemia and renal failure. The patient was on weekly hemodialysis. The peripheral corneal ulceration remained stable until he developed sudden and rapid thinning after eight months of regular follow up and management.Laboratory investigations including immunological studies were negative and we had to rely on treatment based on clinical signs, including the visual acuity, size, depth and staining of the ulcer and perilimbal, episcleral, scleral, corneal and anterior chamber reactions. The patient was treated with medical and conservative approaches and the eye was protected with a plastic shield to avoid injury. Despite our efforts, the patient perforated his eye due to a trivial trauma during sleep. He was managed successfully with cyanoacrylate glue and a bandage contact lens. The anterior chamber reformed after the perforation was sealed and the patient is on a regular follow up with a multidisciplinary approach.  相似文献   
35.
The purpose of this study was to investigate the mediating effect of spiritual well-being (SWB) on depressive symptoms (DS) and health-related quality of life (HRQOL) among Taiwanese elders. A convenience sample of 150 Taiwanese elders completed self-administrated questionnaires participated in this cross-sectional study. This study revealed that SWB was positively related to HRQOL but negatively correlated with DS. Results of hieratical regression analyses suggested that SWB significantly mediated the relationship between DS and mental components of HRQOL. Findings from this study suggest that nurses and health care providers should develop strategies to enhance spiritual well-being when caring for elders to maintain good health and promote quality of life.  相似文献   
36.

Background

To our knowledge this is the first published estimate of the charges of the care of burns in Sweden. The Linköping Burn Interventional Score has been used to calculate the charges for each burned patient since 1993. The treatment of burns is versatile, and depends on the depth and extension of the burn. This requires a flexible system to detect the actual differences in the care provided. We aimed to describe the model of burn care that we used to calculate the charges incurred during the acute phase until discharge, so it could be reproduced and applied in other burn centres, which would facilitate a future objective comparison of the expenses in burn care.

Methods

All patients admitted with burns during the period 2010–15 were included. We analysed clinical and economic data from the daily burn scores during the acute phase of the burn until discharge from the burn centre.

Results

Total median charge/patient was US$ 28 199 (10th–90th centiles 4668-197 781) for 696 patients admitted. Burns caused by hot objects and electricity resulted in the highest charges/TBSA%, while charges/day were similar for the different causes of injury. Flame burns resulted in the highest mean charges/admission, probably because they had the longest duration of stay. Mean charges/patient increased in a linear fashion among the different age groups.

Conclusion

Our intervention-based estimate of charges has proved to be a valid tool that is sensitive to the procedures that drive the costs of the care of burns such as large TBSA%, intensive care, and operations. The burn score system could be reproduced easily in other burn centres worldwide and facilitate the comparison regardless of the differences in the currency and the economic circumstances.  相似文献   
37.
38.
39.
Although some bariatric guidelines reserve pre-operative trans-abdominal ultrasonography screening for symptomatic patients and those with elevated liver enzymes, there has yet to exist a general consensus regarding this issue. Some centers still employ its use as a vital step in the workup of the bariatric patient. This study aims to observe the prevalent findings on routine pre-operative trans-abdominal ultrasonography when used as a screening tool prior to laparoscopic sleeve gastrectomy (LSG). All patients undergoing LSG were screened pre-operatively with trans-abdominal ultrasonography. A retrospective study was done of the pre-operative ultrasonography results of patients who underwent LSG at Amiri Hospital from 2008 to 2012. A total of 747 patients were included in the study, with a median age of 36 (15–68). Five hundred ninety (79.0 %) patients were females while 157 (21.0 %) were males, with an overall median body mass index (BMI) of 45 (30–90). Two hundred forty patients (32.1 %) had normal pre-operative ultrasonography results, 83 (11.1 %) were found to have gallstones, 427 (57.2 %) had fatty liver, and 55 (7.4 %) had other pathologies. There was no statistically significant association between BMI and gallstones (p?=?0.545) and BMI and fatty liver (p?=?0.418). Trans-abdominal ultrasonography screening prior to LSG revealed a wide range of findings but does not add significant information to the pre-operative workup of patients undergoing the procedure and should be reserved for indicated patients.  相似文献   
40.
The present study was designed to investigate the toxico-pathological effect of cadmium (Cd) and its amelioration with silymarin (SL) and milk thistle (MT) in male Japanese quail (Coturnix japonica). A total of 144 male quail were divided into nine equal groups (A–I). Experimental feeds were offered to these groups containing different combinations of Cd chloride (Cd1: 150 and Cd2: 300?mg/kg feed), SL (250?mg/kg of feed), and MT (10?g/kg of feed). The duration of the experiment was 60 days. The physical parameters studied included feed intake and body weight. Hematobiochemical parameters included total protein, albumin, ALT, AST, creatinine, urea, hemoglobin, and hematocrit. The data were analyzed by analysis of variance (ANOVA) technique, and group means were compared by Duncan’s multiple range test. The body weight decreased significantly in Cd-treated groups while SL and MT ameliorated the toxic effects of Cd as compared to control group. The hemoglobin (Hb) concentration and hematocrit (Hct) values were decreased significantly in Cd2-treated group, while Hb and Hct decreased nonsignificantly in Cd1-treated group compared with control. Similar hematological findings were observed, when Cd was used in combinations with SL and MT. Urea, creatinine, and AST increased significantly, while ALT increased nonsignificantly in Cd-treated groups as compared to control group, while total protein, albumin, and globulin decreased significantly in Cd-treated groups as compared to control group. The SL and MT completely ameliorated these toxic effects at low dose of Cd; however, amelioration was partial at higher doses of Cd. These compounds (SL &; MT) might be used to ameliorate toxic effects of Cd in Japanese quail.  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