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   2850篇
  免费   162篇
  国内免费   22篇
耳鼻咽喉   10篇
儿科学   122篇
妇产科学   12篇
基础医学   377篇
口腔科学   59篇
临床医学   151篇
内科学   775篇
皮肤病学   53篇
神经病学   263篇
特种医学   82篇
外科学   402篇
综合类   17篇
预防医学   64篇
眼科学   103篇
药学   218篇
中国医学   8篇
肿瘤学   318篇
  2023年   12篇
  2022年   40篇
  2021年   51篇
  2020年   36篇
  2019年   41篇
  2018年   59篇
  2017年   51篇
  2016年   59篇
  2015年   61篇
  2014年   75篇
  2013年   114篇
  2012年   184篇
  2011年   189篇
  2010年   94篇
  2009年   82篇
  2008年   142篇
  2007年   181篇
  2006年   181篇
  2005年   177篇
  2004年   172篇
  2003年   174篇
  2002年   181篇
  2001年   24篇
  2000年   28篇
  1999年   43篇
  1998年   46篇
  1997年   36篇
  1996年   46篇
  1995年   30篇
  1994年   33篇
  1993年   43篇
  1992年   25篇
  1991年   26篇
  1990年   32篇
  1989年   27篇
  1988年   15篇
  1987年   18篇
  1986年   26篇
  1985年   17篇
  1984年   13篇
  1983年   11篇
  1982年   10篇
  1980年   10篇
  1978年   8篇
  1977年   8篇
  1976年   7篇
  1974年   12篇
  1973年   8篇
  1972年   8篇
  1966年   8篇
排序方式: 共有3034条查询结果,搜索用时 15 毫秒
81.
Recently, an aortic valve area (AVA) index (AVAI) <0.6 cm(2)/m(2) was proposed as an indicator of severe aortic stenosis. The purpose of the present study was to clarify the prognostic value of the AVAI. We identified 103 consecutive asymptomatic patients (mean age 72 ± 11 years) with severe aortic stenosis, defined by an AVA of <1.0 cm(2), who had not undergone aortic valve replacement on initial evaluation. During follow-up (median 36 ± 27 months), 31 aortic valve replacements and 20 cardiac deaths occurred. Multivariate analysis revealed that an AVAI <0.6 cm(2)/m(2) (hazard ratio 2.6, 95% confidence interval 1.1 to 6.3; p = 0.03) and peak aortic jet velocity (Vp) >4.0 m/s (hazard ratio 2.6, 95% confidence interval 1.2 to 5.8; p = 0.02) were associated with cardiac events but that an AVA <0.75 cm(2) was not. The event-free survival of patients with an AVAI of ≥0.6 cm(2)/m(2) was better than that for those with an AVAI <0.6 cm(2)/m(2) (86% vs 41% at 3 years, p <0.01). Furthermore, patients with an AVAI of ≥0.6 cm(2)/m(2) and Vp of ≤4.0 m/s showed an excellent prognosis, but those without these findings had poorer outcomes. In conclusion, AVAI is a powerful predictor of adverse events in asymptomatic patients with severe aortic stenosis. Furthermore, the combination of AVAI and Vp provides additional prognostic information. Watchful observations are required for timely aortic valve replacement in patients with an AVAI of <0.6 cm(2)/m(2) or a Vp >4.0 m/s.  相似文献   
82.
83.
84.
85.
We retrospectively investigated the ability of adalimumab (ADA) to reduce disease activity, improve physical function, and retard the progression of structural damage in 167 patients with rheumatoid arthritis. Clinical and functional outcomes were compared between patients with or without prior biologic treatment and those with or without concomitant methotrexate (MTX) treatment. At week 52, 38.3% achieved clinical remission: 42.4 and 28.6% of patients achieved remission in those without and with previous biologics, respectively, while 42.7 and 12.5% of patients achieved remission in those with and without concomitant MTX, respectively. ADA treatment significantly reduced the rate of radiographic progression from 27.1 ± 46.0 (median 13.6; 25th-75th percentiles 8.3 to 28.9) at baseline to 0.8 ± 5.0 (median 0.0; 25th-75th percentiles -0.9 to 2.0) at week 52 (P < 0.0001). Radiographic progression was absent in 59.8% of patients. Sixty adverse events (34.21/100 patient-years) were reported, 16 of which were serious (9.12/100 patient-years). ADA therapy is highly effective for reducing disease activity, improving physical function, and limiting radiographic progression. It is generally safe and well tolerated by Japanese RA patients in routine clinical practice.  相似文献   
86.
The treatment of rheumatoid arthritis (RA) has improved dramatically with the advent of the latest generation of disease-modifying antirheumatic drugs. Despite these advances, in some patients inflammation is not diminished sufficiently to prevent irreversible musculoskeletal damage, thereby necessitating surgical intervention to reduce pain and improve function. For RA treatment, Japanese orthopedic surgeons also prescribe medication. In this study, we examined whether this Japanese system is effective for RA treatment. We analyzed the clinical condition of RA patients treated by rheumatologists and those treated by orthopedists in a linked registry study using information from a large observational cohort of RA patients followed every half year from 2000 to 2010 (the IORRA cohort). Two groups of patients were compared: patients treated by rheumatologists (rheumatologic group) and patients treated by orthopedists (orthopedic group). The results revealed that patients in the orthopedic group were older, more likely to be female, and had a longer disease duration than patients in the rheumatologic group. The proportion of patients with a history of joint surgery was also much higher in the orthopedic group than in the rheumatologic group. The average scores on the Japanese version of the Health Assessment Questionnaire, and the remission ratio determined using a Boolean-based definition gradually increased from 2000 until 2010, and these findings were consistently better in the rheumatologic group than in the orthopedic group. These data suggest that patients treated primarily by orthopedists are more likely to have long-standing RA compared to patients treated by rheumatologists. Therefore, it is critical for rheumatologists and orthopedists to complement each other medically in the treatment of RA patients.  相似文献   
87.
88.

Purpose

Hyponatremia in hospitalized patients has been reported to be associated with in-hospital mortality. We studied patients treated at our hospital for hip fracture regarding the factors related to hyponatremia at admission.

Methods

Among 580 patients aged 60 years or above who were admitted to our hospital since January 1997 for treatment of hip fracture, 512 patients (110 males, 402 females) from whom serum sodium level at admission was available were studied. In 512 patients, the age at injury ranged from 60 to 103 (mean 82.6) years. Fracture types were femoral neck fracture in 191 patients, and trochanteric fracture in 321. These patients were divided into two groups by the blood sodium level at admission: a hyponatremia group with sodium levels lower than 135 mEq/L, and a normonatremia group with sodium levels within normal range. The age, gender, fracture type, residence before injury, pre-injury walking capability, anemia at admission, liver function, kidney function, inflammatory status, urinary glucose status, lung disease, ECG abnormality, systemic chronic disease, status of dementia, treatment modality, hospital stay (days), and in-hospital death were investigated. First a univariate study was conducted to identify the factors that differ significantly between the two groups. Then multivariate analysis was conducted using the parameters with significant difference as independent variables

Results

Hyponatremia was found in 49 of 512 (9.6 %) patients. In univariate analyses, six factors (age; residence before injury; anemia; dementia; treatment modality; in-hospital death) were significantly different between the hyponatremia group and normonatremia group. Multivariate analysis identified in-hospital death [odds ratio (OR) = 3.64, p = 0.035] and age (OR = 1.05, p = 0.029) as independently associated with hypernatremia.

Conclusion

Hyponatremia at admission is prevalent in old aged patients with fracture, and is related to in-hospital death.  相似文献   
89.

Background context

Localized amyloid deposits result in a mass, that is, so-called amyloidoma; it has been reported in every anatomic site, although systemic amyloid deposition is much more common. However, primary lumbar epidural amyloidoma without bony involvement is extremely rare. To the best of our knowledge, only one case has been reported previously.

Purpose

To report and review the clinical presentations, imaging studies, and treatment of epidural and paravertebral amyloidoma.

Study design

A case report and review of the literature.

Methods

Lumbar epidural and paravertebral amyloidoma in a 75-year-old man with neurologic compromise is presented. Laminectomy with mass resection was performed.

Results

After surgery, almost complete neurologic improvement was observed. Histologically, definite diagnosis was obtained only after the specific staining of tissue. No sign of local recurrence was evident 1 year after surgery.

Conclusions

Primary amyloidoma, although rare, should be included in the differential diagnosis of epidural mass of the spine. Diagnosis before surgery is difficult as there were no characteristic findings in clinical and imaging studies. Special histologic technique and stains are useful to make a definite diagnosis.  相似文献   
90.
Phenylketonuria (PKU) and related hyperphenylalaninemia (HPA) are caused by a deficiency in hepatic phenylalanine hydroxylase (PAH). The incidence of PKU in Nagasaki prefecture is higher than that in all parts of Japan (1/15 894 vs 1/120 000). To investigate the genetic background of patients with HPA in Nagasaki prefecture, mutation analysis was done in 14 patients with PKU or mild HPA. Homozygous or compound heterozygous PAH mutations were identified in all the patients. The spectrum of PAH mutations in the cohort was broad and similar to those in all parts of Japan and East Asian countries. R53H is the most common mutation in patients with mild HPA. The present results provide further support for genotype–phenotype correlations in patients with HPA. The high incidence of PKU in Nagasaki, the westernmost part of Japan, might be due to migration of people with PAH mutations from China and Korea, and geographic factors.  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