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   2114篇
  免费   138篇
  国内免费   10篇
耳鼻咽喉   18篇
儿科学   31篇
妇产科学   30篇
基础医学   319篇
口腔科学   72篇
临床医学   202篇
内科学   613篇
皮肤病学   72篇
神经病学   111篇
特种医学   60篇
外科学   234篇
综合类   2篇
一般理论   2篇
预防医学   129篇
眼科学   36篇
药学   180篇
中国医学   5篇
肿瘤学   146篇
  2023年   24篇
  2022年   34篇
  2021年   79篇
  2020年   38篇
  2019年   52篇
  2018年   69篇
  2017年   41篇
  2016年   50篇
  2015年   57篇
  2014年   74篇
  2013年   92篇
  2012年   171篇
  2011年   170篇
  2010年   107篇
  2009年   87篇
  2008年   132篇
  2007年   155篇
  2006年   112篇
  2005年   125篇
  2004年   111篇
  2003年   84篇
  2002年   92篇
  2001年   13篇
  2000年   33篇
  1999年   37篇
  1998年   10篇
  1997年   11篇
  1996年   12篇
  1995年   17篇
  1994年   13篇
  1993年   5篇
  1992年   22篇
  1991年   20篇
  1990年   12篇
  1989年   16篇
  1988年   10篇
  1987年   8篇
  1986年   10篇
  1985年   12篇
  1984年   5篇
  1983年   3篇
  1980年   4篇
  1979年   7篇
  1978年   2篇
  1976年   2篇
  1975年   2篇
  1974年   3篇
  1972年   4篇
  1971年   2篇
  1967年   4篇
排序方式: 共有2262条查询结果,搜索用时 31 毫秒
71.
72.

Objectives

The number of teeth has frequently been used as an indicator of oral health in investigations of food intake; however, this measure does not represent the efficacy of the masticatory performance. Masticatory performance may be more important for food selection and avoidance than number of remaining teeth. The aim of this study was to investigate the association of occlusal force with habitual dietary intakes in independently living older Japanese.

Methods

The study population was 757 community-dwelling people aged 69–71 years old. Bilateral maximal occlusal force in the intercuspal position was measured with pressure-sensitive sheets. Removable denture wearers kept their dentures in place during the measurements. Dietary habits during the preceding month were assessed using a brief-type self-administered diet history questionnaire that measures consumption frequencies of selected food commonly consumed and calculates energy-adjusted dietary intakes. Linear trends of food and nutrient intakes with decreasing occlusal force were tested after adjusting for gender and socioeconomic factors.

Results

After adjusting for socioeconomic status and the number of remaining teeth, decline of occlusal force was significantly associated with lower intakes of vegetables, vitamins A, C, B6, folate, and dietary fibre (P for trend < 0.05). In contrast, number of teeth was significantly associated only with calcium and zinc, controlling for occlusal force.

Conclusions

It is concluded that occlusal force was significantly associated with intakes of vitamins and dietary fibre rather than number of remaining teeth in independently living older Japanese.  相似文献   
73.
Achilles tendon xanthoma (ATX) is one of the typical features of familial hypercholesterolemia (FH). The morphological evaluation of ATX by X-ray radiography is widely recognized; however, the utility of other imaging modalities remains unclear. We herein report two cases of FH in which Doppler ultrasound imaging demonstrated a microvascular flow in ATX that only rarely could be observed in normal Achilles tendons. Neoangiogenesis accompanies chronic inflammation and it may play an important role in the deposition of cholesterol crystals leading to ATX. In addition to the morphological evaluation of ATX, the assessment of neoangiogenesis may therefore be essential for the evaluation of ATX.  相似文献   
74.
75.
Streptococcus thermophilus bacteria, which are widely used as fermented starter for dairy production, exert various beneficial health effects. Nevertheless, even though pro-longevity effects of various probiotics have been reported, no report has described Streptococcus thermophilus effects on longevity. This study was conducted to evaluate Streptococcus thermophilus effects on lifespan extension and to elucidate the Streptococcus thermophilus-mediated longevity mechanism using Caenorhabditis elegans worms as a model animal. They were fed standard food (Escherichia coli OP50) or Streptococcus thermophilus from the young adult stage. Feeding with Streptococcus thermophilus, compared to Escherichia coli OP50, to Caenorhabditis elegans extend the lifespan, reduced lipofuscin accumulation, and maintain vigorous locomotion. Feeding with Streptococcus thermophilus did not alter the worm growth curve or the offspring number, indicating that the Streptococcus thermophilus-mediated lifespan extension is not attributable to caloric restriction. The qRT-PCR data showed that Streptococcus thermophilus increased the expression of daf-16 and some of its downstream antioxidant genes. Furthermore, the pro-longevity effects of Streptococcus thermophilus were decreased in loss-of-function mutant of daf-16. Results show that Streptococcus thermophilus extends the lifespan of Caenorhabditis elegans through DAF-16-mediated antioxidant pathway activation.  相似文献   
76.
European Archives of Oto-Rhino-Laryngology - Papillary thyroid carcinoma frequently metastasizes to central and lateral neck lymph nodes, but metastasis to retropharyngeal lymph nodes (RPLN) is...  相似文献   
77.
We examined the relation between adalimumab and infliximab plasma trough levels, anti‐adalimumab and anti‐infliximab antibody formation. We analyzed plasma from 32 adalimumab‐treated and 20 infliximab‐treated psoriasis patients for evaluating trough levels of each drug. The presence of anti‐adalimumab and anti‐infliximab antibodies was analyzed and the severity of psoriasis was evaluated. At week 28, 25 out of 32 and at week 48, 21 out of 30 adalimumab‐treated patients maintained as more than PASI 75. At week 28, 12 out of 20 and at week 48, nine out of 18 infliximab‐treated patients were evaluated as more than PASI 75. In patients treated with 40 mg adalimumab every other week, the mean trough level was 7.62 μg/mL (range, 0.05–10.6) at week 48. In patients treated with 80 mg adalimumab every other week, the mean trough level was 8.61 μg/mL (range, 0.08–13.5) at week 48. Mean trough level of infliximab‐treated cases (4.1–5.2 mg/kg; mean, 4.6) was 4.64 μg/mL (range, 0.03–16.9) at week 48. Anti‐adalimumab antibody was detected in five out of 32 cases and anti‐infliximab antibody was detected in six out of 20 cases, respectively, at weeks 24 and 48. The optimal cut‐off values of adalimumab and infliximab concentration for more than PASI 75 were more than 7.84 μg/mL and more than 0.92 μg/mL, respectively. The trough levels of adalimumab and infliximab in psoriasis patients were positively associated with clinical response and were significantly lower in cases having anti‐adalimumab or anti‐infliximab antibodies.  相似文献   
78.
79.
Ellagic acid (EA), a natural polyphenol found in berries, has high antioxidant capacity. This study aimed to improve EA solubility by complex formation with urea (UR) using solvent evaporation method and evaluate its solubility, antioxidant capacity, and physical properties. The solubility test (25 °C, 72 h) showed that the solubility of EVP (EA/UR = 1/1) was approximately two-fold higher than that of EA (7.13 µg/mL versus 3.99 µg/mL). Moreover, the IC50 values of EA and EVP (EA/UR = 1/1) (1.50 µg/mL and 1.30 µg/mL, respectively) showed higher antioxidant capacity of EVP than that of EA. DSC analysis revealed that the UR peak at 134 °C disappeared, and a new endothermic peak was observed at approximately 250 °C for EVP (EA/UR = 1/1). PXRD measurements showed that the characteristic peaks of EA at 2θ = 12.0° and 28.0° and of UR at 2θ = 22.0°, 24.3°, and 29.1° disappeared and that new peaks were identified at 2θ = 10.6°, 18.7°, and 26.8° for EVP (EA/UR = 1/1). According to 2D NOESY NMR spectroscopy, cross-peaks were observed between the -NH and -OH groups, suggesting intermolecular interactions between EA and UR. Therefore, complexation was confirmed in EA/UR = 1/1 prepared by solvent evaporation, suggesting that it contributed to the improvement in solubility and antioxidant capacity of EA.  相似文献   
80.
BACKGROUND: DISC1 has been suggested as a causative gene for psychoses in a large Scottish family. We recently identified FEZ1 as an interacting partner for DISC1. To investigate the role of FEZ1 in schizophrenia and bipolar disorder, case-control association analyses were conducted in Japanese cohorts. METHODS: We performed a mutation screen of the FEZ1 gene and detected 15 polymorphisms. Additional data on informative polymorphisms were obtained from public databases. Eight single nucleotide polymorphisms (SNPs) were analyzed in 119 bipolar disorder and 360 schizophrenic patients and age- and gender-matched control subjects. All genotypes were determined with the TaqMan assay, and selected samples were confirmed by sequencing. RESULTS: The two adjacent polymorphisms displayed a nominally significant association with schizophrenia (IVS2+ 1587G>A, p = .014; 396T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