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   2220篇
  免费   189篇
  国内免费   18篇
耳鼻咽喉   16篇
儿科学   101篇
妇产科学   108篇
基础医学   256篇
口腔科学   108篇
临床医学   290篇
内科学   384篇
皮肤病学   59篇
神经病学   159篇
特种医学   37篇
外国民族医学   1篇
外科学   159篇
综合类   56篇
现状与发展   1篇
一般理论   1篇
预防医学   195篇
眼科学   40篇
药学   251篇
中国医学   44篇
肿瘤学   161篇
  2024年   9篇
  2023年   48篇
  2022年   130篇
  2021年   160篇
  2020年   124篇
  2019年   137篇
  2018年   177篇
  2017年   135篇
  2016年   121篇
  2015年   106篇
  2014年   118篇
  2013年   165篇
  2012年   226篇
  2011年   195篇
  2010年   108篇
  2009年   67篇
  2008年   88篇
  2007年   107篇
  2006年   64篇
  2005年   47篇
  2004年   35篇
  2003年   20篇
  2002年   14篇
  2001年   2篇
  2000年   5篇
  1999年   4篇
  1998年   3篇
  1997年   4篇
  1996年   2篇
  1995年   1篇
  1994年   2篇
  1993年   1篇
  1991年   1篇
  1980年   1篇
排序方式: 共有2427条查询结果,搜索用时 0 毫秒
71.
Occlusal scheme is a controversial topic that has been linked to patient satisfaction with conventional complete dentures (CCDs). This study aimed to compare the patient satisfaction with CCDs with four different occlusal schemes namely the lingualised occlusion (LO), buccalised occlusion (BO), fully bilateral balanced occlusion (FBBO) and partially group function occlusion (PGFO). In this clinical study, new CCDs were made for 121 patients; out of which, 97 patients (mean age of 57.87 ± 9.5 years) completed the 1-year follow-up. The CCD wearers were followed up at 1 month, 3 months and 1 year after CCD delivery. Data were collected via an interview and recorded in a checklist by a blinded examiner. The checklist included the demographic variables, the 19-item version of Oral Health Impact Profile for Edentulous Patients (OHIP-EDENT), and seven 100-mm line visual analogue scales (VASs) to assess the items related to patient satisfaction. The Kruskal-Wallis and Friedman tests followed by post hoc tests were used to compare the variables among the 4 groups and between the 3 follow-ups. P-value ≤ .05 was considered statistically significant for all tests. The patients with BO presented higher satisfaction scores for comfort, stability and retention at the 1-year follow-up compared with PGFO. Both PGFO and FBBO groups had higher physical pain scores compared with BO and LO. The psychological discomfort scores of FBBO group were significantly higher than those in LO group. Pairwise comparisons revealed no significant differences in the general patient satisfaction and total OHIP-EDENT scores between the 4 groups. For most items, within-group analysis showed significant improvement of the satisfaction scores and reduction of domain scores over time.  相似文献   
72.
73.
74.
During development of the primary olfactory system, axon targeting is inaccurate and axons inappropriately project within the target layer or overproject into the deeper layers of the olfactory bulb. As a consequence there is considerable apoptosis of primary olfactory neurons during embryonic and postnatal development and axons of the degraded neurons need to be removed. Olfactory ensheathing cells (OECs) are the glia of the primary olfactory nerve and are known to phagocytose axon debris in the adult and postnatal animal. However, it is unclear when phagocytosis by OECs first commences. We investigated the onset of phagocytosis by OECs in the developing mouse olfactory system by utilizing two transgenic reporter lines: OMP‐ZsGreen mice which express bright green fluorescent protein in primary olfactory neurons, and S100β‐DsRed mice which express red fluorescent protein in OECs. In crosses of these mice, the fate of the degraded axon debris is easily visualized. We found evidence of axon degradation at embryonic day (E)13.5. Phagocytosis of the primary olfactory axon debris by OECs was first detected at E14.5. Phagocytosis of axon debris continued into the postnatal animal during the period when there was extensive mistargeting of olfactory axons. Macrophages were often present in close proximity to OECs but they contributed only a minor role to clearing the axon debris, even after widespread degeneration of olfactory neurons by unilateral bulbectomy and methimazole treatment. These results demonstrate that from early in embryonic development OECs are the primary phagocytic cells of the primary olfactory nerve. J. Comp. Neurol. 523:479–494, 2015. © 2014 Wiley Periodicals, Inc.  相似文献   
75.
The International Journal of Cardiovascular Imaging - Anthracycline agents are routinely used for treatment of many types of malignancy, while imposing the risk for cardiotoxicity (AT-CMP)....  相似文献   
76.
77.
Ultrasound treatment has been shown to enhance the uptake of both hydrophilic and hydrophobic compounds into PC3 and Huvec cell lines using an insonation regimen of a single 10-s burst of high-frequency (4 MHz), moderate intensity (32 W/cm(2)) ultrasound. The purpose of this work was to evaluate the effect of this ultrasound regimen on the cellular accumulation of paclitaxel (PTX) loaded in copolymer micellar of methoxy poly(ethylene glycol)-block-poly(D,L-lactide) (MePEG-b-PDLLA) in both drug-sensitive (MDCKII and MCF-7) and P-glycoprotein (Pgp)-expressing (MDCKII-MDR and NCI-ADR) cell lines. There were no effects of ultrasound on hydrodynamic diameters of micelles and the release of FRET pairs, indicating the integrity of micelles was maintained. There was a two-fold increase in intracellular PTX for all ultrasound-treated drug-sensitive cell lines and their respective drug-resistant counterparts compared with no ultrasound. Significant decreases in drug efflux rates were observed at 20, 40 and 60 min for both drug-sensitive and -resistant cell lines receiving ultrasound. The enhanced accumulation and retention of PTX by ultrasound resulted in greater cytotoxicity in both MDCKII and MDCKII-MDR cell lines, as indicated by the MTS assay. These data suggest that ultrasound may facilitate the uptake of intact paclitaxel-loaded micelles into cells, allowing greater retention of drug in both Pgp and non-Pgp-expressing cells.  相似文献   
78.
A traditional belief in Iranian culture indicates that parental consumption of chicory leaves (Chicorium intybus L.) affects the gender of newborns. The aim of this study was to investigate the effect of aqueous extract of chicory on offspring sex ratio in rat. All rats in experimental groups 1 and 2 were i.p. injected with either 1.0 or 0.7 g/kg body weight (LD50 = 2.244 g/kg) of an aqueous extract of chicory leaves for 30 days at 72 h intervals. The control rats were injected with distilled water in the same manner. After the 8th injection, blood pH, and Na+, K+, Ca2+ and Mg2+ serum levels, were measured in all groups. On day 30, all the rats were mated within and between groups. The results revealed that in comparison with the control group, there were significant increases (p < 0.01) in Na+ and K+ levels, as well as the sex ratio of male to female offspring (10.23%) in experimental group 1. Therefore, it can be concluded that the administration of chicory leaf extract has a significant effect on the sex ratio of the rat offspring. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
79.
BACKGROUND: A parental history of cardiovascular disease has a strong relationship with risk factor clusters in the offspring. This study was performed to identify major cardiovascular risk factors in middle school-aged children and their parents in both high and low-risk families. DESIGN: A school-based, cross-sectional study. METHODS: The middle schools of the 6th district of Tehran were divided randomly into two groups. A total of 169 high-risk children with their families were recruited from the first group and 105 low-risk children with their families were recruited from the second group of schools. Anthropometric and metabolic measurements were performed. RESULTS: The means of the waist circumference and waist-to-hip ratio were significantly higher in high-risk fathers. The means of total and low-density lipoprotein (LDL) cholesterol were significantly higher in both parents and children of the high-risk group. The means of the fasting plasma glucose were significantly higher in fathers and offspring of high-risk families. More fathers in high-risk families were smokers. The prevalence of increased total cholesterol, LDL-cholesterol and hyperglycemia (> or = 100 mg/dl) were higher in high-risk parents and children. The prevalence of increased body mass index (> or = 25 kg/m for parents and 85th percentile for children) was higher in fathers and children of high-risk families. CONCLUSIONS: Cardiovascular risk factors are more prevalent and clustered in high-risk families. The screening of high-risk families is essential to prevent the progression of atherosclerosis from childhood and reduce the burden of cardiovascular disease in adulthood.  相似文献   
80.
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