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   355篇
  免费   3篇
  国内免费   3篇
耳鼻咽喉   2篇
儿科学   3篇
妇产科学   16篇
基础医学   29篇
临床医学   60篇
内科学   82篇
皮肤病学   8篇
神经病学   21篇
特种医学   12篇
外科学   79篇
综合类   10篇
预防医学   12篇
眼科学   6篇
药学   14篇
肿瘤学   7篇
  2023年   10篇
  2022年   16篇
  2021年   17篇
  2020年   8篇
  2019年   13篇
  2018年   18篇
  2017年   10篇
  2016年   5篇
  2015年   10篇
  2014年   15篇
  2013年   22篇
  2012年   40篇
  2011年   30篇
  2010年   15篇
  2009年   18篇
  2008年   24篇
  2007年   24篇
  2006年   23篇
  2005年   14篇
  2004年   11篇
  2003年   8篇
  2002年   8篇
  2001年   1篇
  1993年   1篇
排序方式: 共有361条查询结果,搜索用时 15 毫秒
1.
BACKGROUND/PURPOSE: Proper alignment of the prosthesis is critical in total knee replacement (TKR) to minimize long-term wear, risk of osteolysis, and loosening of the prosthesis. This study examined the accuracy of lower limb alignment obtained using a kinematic navigation system for TKR, and the extra time needed to adopt this system. METHODS: From August 2002 to April 2003, 71 patients with knee osteoarthritis underwent 79 primary TKR operations by the same surgical team. Fifty of these operations were performed with the aid of the CT-free kinematic navigation system, and the remaining 29 were performed with conventional manual methods. Results, including operation time, radiographic alignment of the prosthesis and complications, for the two groups were compared. RESULTS: Patients in the kinematic navigation group achieved better accuracy in the coronal plane than the conventional group in terms of postoperative mechanical axis (1.89 +/- 0.63 degrees vs. 3.38 +/- 1.07 degrees ). Less variation was noted in the navigation group (femur: SD 1.88 degrees vs. 7.12 degrees ; tibia: SD 1.54 degrees vs. 2.99 degrees ), although the difference in the mean values was not significant (p = 0.475 and 0.55, respectively). The operation time (from skin to skin) in the navigation group (100.6 +/- 4.3 minutes) was longer than that in the conventional group (92.7 +/- 5.1 minutes; p = 0.027). Two perioperative fractures occurred in the navigation group, both of which were attributed to patient factors as opposed to operation procedures. No major complications such as infection or pulmonary embolism occurred during this study. CONCLUSION: Use of a kinematic navigation system in TKR provides better accuracy than conventional manual methods. The technique is easy to use, has a short learning curve, and requires an additional operation time of less than 10 minutes. Precise alignment can be achieved with the aid of navigation in most cases.  相似文献   
2.
Iron deficiency is the most common micronutrient deficiency in the world. Previous studies have shown that iron deficiency increases oxidative stress and decreases antioxidant enzymes, and studies of male infertility indicated that oxidative stress may affect male reproductive functions. The aim of this study was to investigate the effects of iron supplementation on spermatogenesis and testicular functions in iron-deficient rats. Three-week-old male Sprague Dawley (SD) rats were randomly divided into two groups: an iron-adequate control (AI group, 35 ppm FeSO4) and an iron-deficient group (ID group, <5 ppm FeSO4). After three weeks, the iron-deficient group was divided into an original iron-deficient group and five iron-supplemented groups, the latter fed diets containing different doses of FeSO4 (6, 12, 18, 24, and 35 ppm). After five weeks, blood and testis tissue were analyzed. We presented as median (interquartile range, IQR) for continuous measurements and compared their differences using the Kruskal–Wallis test followed by the Mann–Whitney U test among groups. The results showed that as compared with the AI group, the ID group had significantly lower serum testosterone and poorer spermatogenesis (The medians (QR) were 187.4 (185.6–190.8) of AI group vs. 87.5 (85.7–90.4) of ID group in serum testosterone, p < 0.05; 9.3 (8.8–10.6) of AI group vs. 4.9 (3.4–5.4) of ID group in mean testicular biopsy score (MTBS], p < 0.05); iron supplementation reversed the impairment of testis tissue. In the testosterone biosynthesis pathway, iron supplementation improved the lowered protein expressions of hydroxysteroid dehydrogenases caused by iron deficiency. Additionally, decreased activities of glutathione peroxidase and catalase, and increased cleaved-caspase 8 and caspase 3 expression, were found in the iron-deficient rats. The iron-supplemented rats that received > 12 ppm FeSO4 exhibited improvements in antioxidant levels. In conclusion, iron supplementation can abrogate testis dysfunction due to iron deficiency through regulation of the testicular antioxidant capacity.  相似文献   
3.
This study numerically investigated the deformation of titanium elastic nails prebent at various degrees during implantation into the intramedullary canal of fractured bones and the mechanism by which this prebending influenced the stability of the fractured bone. Three degrees of prebending the implanted portions of the nails were used: equal to, two times, and three times the diameter of the intramedullary canal. Furthermore, a simulated diaphyseal fracture with a 5-mm gap was created in the middle shaft portion of the bone fixed with two elastic nails in a double C-type configuration. End caps were simulated using a constraint equation. To confirm that the simulation process is able to present the mechanical response of the nail inside the intramedullary, an experiment was conducted by using sawbone for validation. The results indicated that increasing the degrees of nail prebending facilitated straightening the nails against the inner aspect of canal after implantation, with increase in stability under torsion. Furthermore, reducing nail prebending caused a larger portion of the nails to move closer to the loading site and center of bone after implantation; the use of end caps prevented the nail tips from collapsing and increased axial stability. End cap use was critical for preventing the nail tips from collapsing and for increasing the stability of the nails prebent at a degree equal to the diameter of the canal with insufficient frictional force between the nail and canal. Therefore, titanium elastic nail prebending in a double C-type configuration with a degree three times the diameter of the canal represents a superior solution for treating transverse fractures without a gap, whereas that with a degree equal to the diameter of the intramedullary canal and combined with end cap use represents an advanced solution for treating comminuted fractures in a diaphyseal long bone fracture.  相似文献   
4.
5.
Abstract:   The majority of extramedullary plasmacytomas involve the upper respiratory tract but only a few are associated with serum monoclonal gammopathy. Most extramedullary plasmacytomas respond to local radiotherapy and have a better prognosis than multiple myeloma. Solitary plasmacytomas, involving the pleura, are very rare. This case report describes a patient with a solitary extramedullary plasmacytoma involving the pleura, and no evidence of serum, urine or pleural fluid paraproteins. Diagnosis was made by strongly positive immunohistochemical stains with CD38, CD138 and MUM-1 of the pleural tumour. The response to both radiotherapy and chemotherapy was poor and the patient died shortly after diagnosis.  相似文献   
6.

Background and Objectives

Patients with chronic obstructive pulmonary disease (COPD) often have poor health-related quality of life (HRQL), exercise capacity and cardiopulmonary function. Pulmonary rehabilitation (PR) is beneficial to improve exercise capacity and HRQL. However, series changes of these parameters remain unclear.

Methods

Forty-three subjects participated in a 3-months PR program. Subjects were evaluated at baseline and at 8, 16, and 24 sessions after PR.

Results

After 8 sessions, there were significant improvements in the SGRQ-symptom domain, exertional dyspnea, and oxygen pulse (all p < 0.05). Maximal VO2, SGRQ-activity and SGRQ-impact domains, and respiratory muscle strength were significantly improved after 16 and 24 sessions (all p < 0.05).

Conclusions

Eight sessions of exercise training lead to improvement of symptoms and exertional dyspnea. 16 to 24 sessions result in further improvement. We suggest patients receive 16 to 24 sessions of PR.  相似文献   
7.
Persons with Parkinson’s disease (PD) often exhibit difficulties with dexterity during the performance of activities of daily living (ADL), inter alia due to dysfunctional supplementary motor area (SMA). Combined intermittent theta-burst stimulation (iTBS) over the SMA followed by video game-based training (VBT) may therefore improve dexterity related ADL. The VBT may induce high flow levels related to high performance during the training. The aim of this study is to evaluate the feasibility of a combined iTBS-VBT intervention in persons with PD. A total of nine persons with PD (mean age 63.3?±?8.76 years) with self-reported difficulties with dexterity related ADL were included in this pilot iTBS-VBT study. All participants received either iTBS or sham stimulation over the SMA followed by a 45-min VBT, three times a week for a total of three weeks. Feasibility was measured by means of the adherence rate and the system usability (System Usability Scale). Moreover, flow was measured after the last VBT session. Adherence rate was excellent with 100%. High system usability scores (i.e., mean 80%, range 55–97.5) and a significant Spearman’s correlation with the Flow State Scale (r?=?.762, p?=?.017) further point to the high feasibility of the VBT. Neither demographic variables nor difficulties in dexterity related ADL affected the usability of the VBT. This study demonstrates the high feasibility of a combined iTBS-VBT intervention. Moreover, the level of self-reported usability was related to flow experience. Whether this kind of combined iTBS-VBT intervention improves dexterity will be evaluated in a randomized controlled trial. Trial registration clincaltrials.gov NCT04699149, date of registration 1. June 2021  相似文献   
8.
Tuberculosis (TB) is a chronic infectious disease caused by Mycobacterium tuberculosis. It is still unknown if TB, like other infectious diseases contributes a poor prognosis in cirrhotic patients. The aim of this study was to investigate the impact of TB on the mortality of cirrhotic patients.National Health Insurance Database, derived from the Taiwan National Health Insurance Program, was used to identify 434 cirrhotic patients with new diagnosis of TB between January 1, 2007 and December 31, 2007. The comparison group consisted of 4340 selected cirrhotic patients without TB in the same period by propensity score matching analysis.The 30-day, 90-day, 1-year and 3-year mortalities were 10.1%, 24.2%, 43.1%, and 63% in the TB group, and 7.9%, 15.5%, 31.2%, and 53.4% in the non-TB group. After Cox proportional hazard regression model adjusted by the patients’ gender, age, and comorbid disorders, the hazard ratios (HR) in cirrhotic patients with TB for 30-day, 30 to 90-day, 90-day to 1-year, and 1 to 3-year mortalities were 1.33 [95% confidence interval (CI) 0.97–1.83], 1.91 (95% CI 1.45–2.51), 1.46 (95% CI 1.16–1.84), and 1.10 (95% CI 0.88–1.37), compared to the non-TB group.In conclusion, TB is a risk factor for the mortality of cirrhotic patients. The effect focused on the 30-day to 1-year after diagnosis of TB.  相似文献   
9.
For patients who are suffering from neurogenic lower urinary tract dysfunction, intermittent urinary catheterization is an efficient way to empty the bladder.1 However, the method may result in various complications. Herein we present a rare complication of extraperitoneal abscess owing to intermittent urinary catheterization in a 62-year-old male who had cervical spine injury and was treated with intermittent urethral catheterization for neurogenic lower urinary tract dysfunction. Treatment and a literature review are also described.  相似文献   
10.
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