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   1805篇
  免费   111篇
  国内免费   20篇
耳鼻咽喉   4篇
儿科学   41篇
妇产科学   27篇
基础医学   278篇
口腔科学   24篇
临床医学   80篇
内科学   418篇
皮肤病学   50篇
神经病学   141篇
特种医学   25篇
外科学   472篇
综合类   7篇
预防医学   23篇
眼科学   20篇
药学   86篇
中国医学   1篇
肿瘤学   239篇
  2023年   18篇
  2022年   19篇
  2021年   41篇
  2020年   31篇
  2019年   38篇
  2018年   58篇
  2017年   49篇
  2016年   49篇
  2015年   63篇
  2014年   81篇
  2013年   74篇
  2012年   101篇
  2011年   129篇
  2010年   69篇
  2009年   56篇
  2008年   110篇
  2007年   107篇
  2006年   104篇
  2005年   99篇
  2004年   104篇
  2003年   80篇
  2002年   58篇
  2001年   16篇
  2000年   11篇
  1999年   36篇
  1998年   22篇
  1997年   25篇
  1996年   21篇
  1995年   13篇
  1994年   16篇
  1993年   16篇
  1992年   26篇
  1991年   28篇
  1990年   19篇
  1989年   16篇
  1988年   13篇
  1987年   16篇
  1986年   14篇
  1985年   13篇
  1984年   8篇
  1983年   9篇
  1982年   6篇
  1981年   6篇
  1980年   5篇
  1979年   6篇
  1978年   4篇
  1977年   4篇
  1973年   5篇
  1972年   4篇
  1971年   3篇
排序方式: 共有1936条查询结果,搜索用时 421 毫秒
61.
Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominantly inherited endocrine tumor syndrome characterized by tumor development in various endocrine organs such as the parathyroid, endocrine pancreas, anterior pituitary and adrenal cortex. The first extensive database for Asian patients with MEN1 was established by the MEN Consortium of Japan. Although the clinical features of Japanese patients with MEN1 are similar to those from Western countries, there are several characteristic differences between them. In particular, gastroenteropancreatic neuroendocrine tumor (GEPNET) is seen in approximately 60 % of patients with MEN1 in Japan. Although its development is the strongest prognostic factor in patients with MEN1, the characteristics of MEN1-associated GEPNET still remain unclear. This is especially true for the differences in clinical features of GEPNET with and without MEN1. Improved long-term survival is obtained by curative surgery for patients with MEN1-associated GEPNET. The current surgical indications are expanding even in patients with hepatic metastases because of the improved surgical outcome. This article reviews the clinical characteristics in these patients with a particular focus on surgery, diagnosis, surgical indications, surgical method, and surgical outcome.  相似文献   
62.

Objective

Recently, we reported that alpha 1A-adrenoceptor (AR) is the main participant in phenylephrine-induced human ureteral contraction. We therefore decided to carry out a prospective randomized study to evaluate the effects of silodosin, a selective alpha 1A AR antagonist, as a medical expulsive therapy (MET) for distal ureteral stones.

Methods

A total of 112 male patients, who were referred to our department for the management of symptomatic unilateral distal ureteral calculi of less than 10 mm, were randomly divided into two groups: group A (56 patients) who were instructed to drink 2 L of water daily and group B (56 patients) who received the same instruction and were also given silodosin (8 mg/daily) for a maximum of 4 weeks. Expulsion rate, expulsion time and need for analgesics were examined.

Results

The expulsion rate was 55.3 % (56 patients) for group A and 72.7 % (55 patients) for group B (P = 0.106). The expulsion rate for <5 mm was 92.9 % (28 patients) for group A and 69.2 % (26 patients) for group B (P = 0.053). The expulsion rate for ≥5 mm was 17.9 % (28 patients) for group A and 75.9 % (29 patients) for group B (P = 0.001). The expulsion time was 13.40 ± 5.90 and 9.29 ± 5.91 days, respectively (P = 0.012). Analgesics were required 1.5 ± 3.1 and 0.3 ± 0.9 times, respectively (P = 0.382). Stone size in expulsion cases was 3.64 ± 1.25 and 5.23 ± 2.32 mm, respectively (P = 0.003).

Conclusions

Stone size has been identified as an important predictive factor for stone expulsion. Therefore, it is important that administration of silodosin can facilitate expulsion of 1.5 mm or larger distal ureteral stones, as compared to control. We believe that silodosin might have potential as a MET for distal ureteral stones.  相似文献   
63.
Renal tubular cell injury induced by oxalate plays an important role in kidney stone formation. Water containing oxygen nano-bubbles (nanometer-sized bubbles generated from oxygen micro-bubbles; ONB) has anti-inflammatory effects. Therefore, we investigated the inhibitory effects of ONB water on kidney stone formation in ethylene glycol (EG)-treated rats. We divided 60 rats, aged 4 weeks, into 5 groups: control, the water-fed group; 100 % ONB, the 100 % ONB water-fed group; EG, the EG treated water-fed group; EG + 50 % ONB and EG + 100 % ONB, water containing EG and 50 % or 100 % ONB, respectively. Renal calcium oxalate (CaOx) deposition, urinary excretion of N-acetyl-β-d-glucosaminidase (NAG), and renal expression of inflammation-related proteins, oxidative stress biomarkers, and the crystal-binding molecule hyaluronic acid were compared among the 5 groups. In the control and 100 % ONB groups, no renal CaOx deposits were detected. In the EG + 50 % ONB and EG + 100 % ONB groups, ONB water significantly decreased renal CaOx deposits, urinary NAG excretion, and renal monocyte chemoattractant protein-1, osteopontin, and hyaluronic acid expression and increased renal superoxide dismutase-1 expression compared with the EG group. ONB water substantially affected kidney stone formation in the rat kidney by reducing renal tubular cell injury. ONB water is a potential prophylactic agent for kidney stones.  相似文献   
64.
To clarify the association between regional variations in urolithiasis incidence and nutrition intake, we evaluated associated data from Japanese national surveys. The incidence of urolithiasis in 12 regions of Japan was calculated from 2005 patient data obtained from 430 hospitals (n = 92,797). Nutrition intake data were obtained from the National Health and Nutrition Survey. We examined the association between urolithiasis incidence and average intake of various types of food or nutrients by region. Continuing surveys in Japan reveal fixed variations in urolithiasis incidence among geographic regions. The national average of patients with urolithiasis was estimated as 203.1 per 100,000 citizens. Regarding food, intake of fruit correlated negatively with the incidence of urolithiasis (r = ?0.721, p = 0.008), while intake of eggs (r = 0.537, p = 0.072) and sugar (r = 0.475, p = 0.119) tended to positively correlate with incidence. Regarding nutrients, intake of potassium (r = ?0.500, p = 0.098), vitamin K (r = ?0.562, p = 0.057), and pantothenic acid (r = ?0.560, p = 0.058) tended to negatively correlate with incidence. The incidence of urolithiasis is higher in geographic areas with populations having low fruit and high sugar intake.  相似文献   
65.

Background

We retrospectively investigated prognostic factors to be used in selecting the patients with stage IV gastric cancer (GC) who have an unfavorable prognosis after palliative gastrectomy.

Methods

A total of 146 GC patients at stage IV who had undergone palliative gastrectomy were enrolled. Various clinicopathological parameters were evaluated for prognosis.

Results

Surgical morbidity and hospital mortality occurred in 35 (23.9 %) and 4 (2.7 %) patients, respectively. The overall 5-year survival rate and the median survival time were 11.2 % and 13.2 months, respectively. Of the 146 patients, 64 had uncomfortable symptoms associated with GC and 76 had no such symptoms. Of the 64 patients with uncomfortable symptoms, 60 (93.7 %) experienced relief of these symptoms after palliative surgery. Multivariate analysis for patients without uncomfortable symptoms associated with GC revealed that the number of incurable factors and serum SPan-1 level were independent prognostic factors.

Conclusions

Patients with stage IV GC who had multiple incurable factors and a high level of serum SPan-1 might not be candidates for palliative gastrectomy for the purpose of prognostic benefit.  相似文献   
66.
67.
68.

Background

Sarcopenic dysphagia is characterized by difficulty swallowing due to a loss of whole-body skeletal and swallowing muscle mass and function. However, no study has reported on swallowing muscle mass and quality in patients with sarcopenic dysphagia.

Objective

To compare the differences in swallowing muscle mass and quality between sarcopenic and nonsarcopenic dysphagia.

Method

A cross-sectional study was performed in 55 older patients, who had been recommended to undergo dysphagia assessment and/or rehabilitation. Sarcopenic dysphagia was diagnosed using a diagnostic algorithm for sarcopenic dysphagia. The thickness and area of tongue muscle and geniohyoid muscle (coronal plane and sagittal plane), and the echo-intensity of the tongue and geniohyoid muscles were examined by ultrasound.

Results

The study participants included 31 males and 24 females (mean age of 82 ± 7 years), with 14 having possible sarcopenic dysphagia, 22 probable sarcopenic dysphagia, and 19 without sarcopenic dysphagia. The group with sarcopenic dysphagia had a significantly lower cross-sectional area and area of brightness of the tongue muscle than that observed in the group without sarcopenic dysphagia. The most specific factor for identifying the presence of sarcopenic dysphagia was tongue muscle area (sensitivity, 0.389; specificity, 0.947; cut-off value, 1536.0), while the factor with the highest sensitivity was geniohyoid muscle area brightness in sagittal sections (sensitivity, 0.806; specificity, 0.632; cut-off value, 20.1). Multivariate logistic regression analysis showed that the area of the tongue muscle and its area of brightness were independent risk factors for sarcopenic dysphagia. However, geniohyoid sagittal muscle area and area of brightness showed no significant independent association with sarcopenic dysphagia.

Conclusion

Tongue muscle mass in patients with sarcopenic dysphagia was smaller than that in patients without the condition. Sarcopenic dysphagia was also associated with increased intensity of the tongue muscle.  相似文献   
69.
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