全文获取类型
收费全文 | 1663篇 |
免费 | 117篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 51篇 |
儿科学 | 36篇 |
妇产科学 | 50篇 |
基础医学 | 270篇 |
口腔科学 | 20篇 |
临床医学 | 135篇 |
内科学 | 421篇 |
皮肤病学 | 27篇 |
神经病学 | 163篇 |
特种医学 | 28篇 |
外科学 | 97篇 |
综合类 | 17篇 |
一般理论 | 1篇 |
预防医学 | 154篇 |
眼科学 | 27篇 |
药学 | 173篇 |
中国医学 | 1篇 |
肿瘤学 | 117篇 |
出版年
2024年 | 2篇 |
2023年 | 36篇 |
2022年 | 124篇 |
2021年 | 179篇 |
2020年 | 71篇 |
2019年 | 80篇 |
2018年 | 90篇 |
2017年 | 63篇 |
2016年 | 81篇 |
2015年 | 78篇 |
2014年 | 73篇 |
2013年 | 110篇 |
2012年 | 153篇 |
2011年 | 144篇 |
2010年 | 65篇 |
2009年 | 52篇 |
2008年 | 81篇 |
2007年 | 70篇 |
2006年 | 73篇 |
2005年 | 59篇 |
2004年 | 36篇 |
2003年 | 34篇 |
2002年 | 24篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1990年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有1788条查询结果,搜索用时 0 毫秒
961.
Protein kinase Cε (PKCε) is a representative member of a family of novel PKC isoforms that are independent of calcium, but can be activated by phorbol esters, diacylglycerol (DAG) and phosphatidylserine (PS). This kinase is capable of modulating crucial cell functions, including proliferation, differentiation and survival. These activities depend on enzyme translocation to subcellular compartments upon binding DAG, PS or exogenous stimulators. PKCε initiates malignant transformation of cells through its effects on the Ras/Raf/MAPK pathway and displays the greatest carcinogenic potential of all PKC isoforms. PKCε also promotes tumor metastatic capacity and resistance to anti-cancer therapy. Overexpression of PKCε is found in numerous cancers including colon, breast, stomach, prostate, thyroid and lung and is considered an important marker of negative disease outcome. Although overexpression of PKCε is observed in tumors, it is not found in healthy tissues hence it has been suggested as a diagnostic marker or a putative target for specific inhibitors used for treatment of cancer. Research on selective inhibition of PKCε is under way and diverse approaches may become clinically applicable anti-tumor strategies. Suppression of the PKCε-encoding gene achieved through the antisense cDNA, suppression of PKCε with RNAi and inhibition achieved with translocation-inhibitory peptides may provide novel treatment strategies for cancer. 相似文献
962.
Cross-sectional study developed to relate the international normalized ratio (INR), used as a parameter to monitor the levels of blood clotting, stability to adherence, age, level of education, socioeconomic level, interaction with other drugs, comorbidities, vitamin K intake, anticoagulation time and drug cost. 156 patients were included, mean age 57 ± 13 years, (53.8%) male, 61 (39.1%) had high adherence, 91 (58.3%) medium and 4 (2.6%) low adherence to treatment, 117 (75%) had INR stability up to 50% and 39 (25%) > 75%, patients with shorter time of anticoagulation presented higher stability, those who spent less on the drug remained more stable and had better adherence. It was concluded that more than 90% of patients had high and medium adherence and that the anticoagulation time and drug cost were the factors related to the anticoagulation stability. 相似文献
963.
Nägler DK Lechner AM Oettl A Kozaczynska K Scheuber HP Gippner-Steppert C Bogner V Biberthaler P Jochum M 《Journal of immunological methods》2006,308(1-2):241-250
The human lysosomal cysteine-type carboxypeptidase cathepsin X is mainly present in monocytes and macrophages and may be released into the circulation due to constitutive and/or regulated secretion by (activated) immune cells. To define its potential diagnostic value as an inflammatory marker, we have developed a highly sensitive and specific sandwich-type immunoassay (ELISA) for cathepsin X permitting both intra- and extracellular detection and quantification. The dynamic range of the cathepsin X ELISA was determined to be 100 (detection limit) to 8000 pg/ml. Reproducibility of both within and between runs yielded coefficients of variation (CVs) of 2.7-3.5% and 6.3-7.3%, respectively. Cross-reactivity with other members (cathepsin B, L) of the thiol-dependent cathepsin family was not observed. The ELISA was used to quantify cathepsin X in leukocytes as well as in plasma of healthy volunteers and patients with multiple trauma. During the first 72 h after trauma, plasma levels of cathepsin X increased significantly, particularly in patients who died during the posttraumatic period. In comparison to the well-known inflammation marker neutrophil elastase, cathepsin X levels predicted survival with a higher significance in the later posttraumatic phase. In conclusion, this report provides the first evidence of cathepsin X immunoreactivity not only in cell lysates but also in plasma samples. We suggest that the newly developed highly reproducible ELISA will be of great value for further evaluation of this protease as a diagnostic and/or prognostic marker in inflammatory diseases. 相似文献
964.
Pulka K 《Current opinion in drug discovery & development》2010,13(6):669-684
The synthesis of biologically active heterocyclic scaffolds is one of the significant challenges of modern synthetic chemistry. The Pictet-Spengler (PS) reaction, known for approximately a century, remains a particularly popular cyclization method. This review describes recent applications of the PS reaction in the total synthesis of alkaloids and biologically active analogs of tetrahydroisoquinoline and tetrahydro-β-carboline. The utility of PS cyclization in the synthesis of a range of heterocyclic scaffolds is also described. 相似文献
965.
Fredrik Anesten Adri Dalmau Gasull Jennifer E. Richard Imre Farkas Devesh Mishra Lilly Taing Fuping Zhang Matti Poutanen Vilborg Palsdottir Zsolt Liposits Karolina P. Skibicka John‐Olov Jansson 《Journal of neuroendocrinology》2019,31(6)
Neuronal circuits involving the central amygdala (CeA) are gaining prominence as important centres for regulation of metabolic functions. As a part of the subcortical food motivation circuitry, CeA is associated with food motivation and hunger. We have previously shown that interleukin (IL)‐6 can act as a downstream mediator of the metabolic effects of glucagon‐like peptide‐1 (GLP‐1) receptor (R) stimulation in the brain, although the sites of these effects are largely unknown. In the present study, we used the newly generated and validated RedIL6 reporter mouse strain to investigate the presence of IL‐6 in the CeA, as well as possible interactions between IL‐6 and GLP‐1 in this nucleus. IL‐6 was present in the CeA, mostly in cells in the medial and lateral parts of this structure, and a majority of IL‐6‐containing cells also co‐expressed GLP‐1R. Triple staining showed GLP‐1 containing fibres co‐staining with synaptophysin close to or overlapping with IL‐6 containing cells. GLP‐1R stimulation enhanced IL‐6 mRNA levels. IL‐6 receptor‐alpha (IL‐6Rα) was found to a large part in neuronal CeA cells. Using electrophysiology, we determined that cells with neuronal properties in the CeA could be rapidly stimulated by IL‐6 administration in vitro. Moreover, microinjections of IL‐6 into the CeA could slightly reduce food intake in vivo in overnight fasted rats. In conclusion, IL‐6 containing cells in the CeA express GLP‐1R, are close to GLP‐1‐containing synapses, and demonstrate increased IL‐6 mRNA in response to GLP‐1R agonist treatment. IL‐6, in turn, exerts biological effects in the CeA, possibly via IL‐6Rα present in this nucleus. 相似文献
966.
967.
Study of top ballet school students revealed large deficiencies in their body weight and body fat 下载免费PDF全文
Elżbieta Grochowska‐Niedworok Marek Kardas Edyta Fatyga Karolina Piórkowska‐Staniek Małgorzata Muc‐Wierzgoń Teresa Kokot 《Acta paediatrica (Oslo, Norway : 1992)》2018,107(6):1077-1082
Aim
This study assessed the nutritional status and physical activity levels of 150 female students aged 10–18 from three top Polish ballet schools, where the most promising dancers go on to pursue professional ballet careers.Methods
We analysed the girls’ body composition, physical activity level (PAL) and PAL coefficient. The ballet students also completed a questionnaire.Results
The results revealed large deficiencies in the body weight and body fat of the young ballerinas. The mean body mass index (BMI) for the group was 16.8 kg/m2. Polish centile charts showed that 18% of the girls had BMIs below the norm and 54% had a lower than average body fat content, with a mean of 15.6%. The body fat content was lowest (13.8%) in the 13‐ to 15‐year age group. On average, girls aged 10–12 had 15.7% body fat, while girls aged 16–18 had 18.4%. The mean values for the anthropometric measurements were higher in older girls. The majority (72%) of the respondents reported high physical activity levels, defined as more than 15 hours of exercise per week.Conclusion
Special attention should be paid to low BMIs and body fat in young ballet school dancers aged 10–15 years. 相似文献968.
Natalia Chmielewska Janusz Szyndler Karolina Makowska Dawid Wojtyna Piotr Maciejak Adam Płaźnik 《Neurologia i neurochirurgia polska》2018,52(3):318-325
The role of blood brain barrier (BBB) is to preserve a precisely regulated environment for proper neuronal signaling. In many of the central nervous system (CNS) pathologies, the function of BBB is altered. Thus, there is a necessity to evaluate a fast, noninvasive and reliable method for monitoring of BBB condition. It seems that revealing the peripheral diagnostic biomarker whose release pattern (concentration, dynamics) will be correlated with clinical symptoms of neurological disorders offers significant hope. It could help with faster diagnosis and efficient treatment monitoring. In this review we summarize the recent data concerning exploration of potential new serum biomarkers appearing in the peripheral circulation following BBB disintegration, with an emphasis on epilepsy, traumatic brain injury (TBI) and stroke. We consider the application of well-known proteins (S100β and GFAP) as serum indicators in the light of recently obtained results. Furthermore, the utility of molecules like MMP-9, UCHL-1, neurofilaments, BDNF, and miRNA, which are newly recognized as a potential serum biomarkers, will also be discussed. 相似文献
969.
970.