全文获取类型
收费全文 | 1081篇 |
免费 | 46篇 |
出版年
2023年 | 11篇 |
2022年 | 13篇 |
2021年 | 20篇 |
2020年 | 24篇 |
2019年 | 25篇 |
2018年 | 32篇 |
2017年 | 24篇 |
2016年 | 35篇 |
2015年 | 45篇 |
2014年 | 57篇 |
2013年 | 73篇 |
2012年 | 94篇 |
2011年 | 71篇 |
2010年 | 51篇 |
2009年 | 48篇 |
2008年 | 65篇 |
2007年 | 61篇 |
2006年 | 50篇 |
2005年 | 37篇 |
2004年 | 42篇 |
2003年 | 38篇 |
2002年 | 37篇 |
2001年 | 8篇 |
2000年 | 5篇 |
1999年 | 3篇 |
1998年 | 4篇 |
1996年 | 4篇 |
1994年 | 4篇 |
1993年 | 4篇 |
1992年 | 11篇 |
1991年 | 10篇 |
1990年 | 7篇 |
1989年 | 12篇 |
1988年 | 8篇 |
1987年 | 5篇 |
1986年 | 8篇 |
1985年 | 8篇 |
1984年 | 6篇 |
1983年 | 6篇 |
1982年 | 5篇 |
1981年 | 7篇 |
1980年 | 4篇 |
1979年 | 3篇 |
1978年 | 5篇 |
1977年 | 5篇 |
1976年 | 4篇 |
1974年 | 5篇 |
1973年 | 9篇 |
1968年 | 2篇 |
1966年 | 2篇 |
排序方式: 共有1127条查询结果,搜索用时 15 毫秒
31.
Neethu Robinson Ali Danish Zaidi Mohit Rana Vinod A. Prasad Cuntai Guan Niels Birbaumer Ranganatha Sitaram 《PloS one》2016,11(7)
Recently, studies have reported the use of Near Infrared Spectroscopy (NIRS) for developing Brain–Computer Interface (BCI) by applying online pattern classification of brain states from subject-specific fNIRS signals. The purpose of the present study was to develop and test a real-time method for subject-specific and subject-independent classification of multi-channel fNIRS signals using support-vector machines (SVM), so as to determine its feasibility as an online neurofeedback system. Towards this goal, we used left versus right hand movement execution and movement imagery as study paradigms in a series of experiments. In the first two experiments, activations in the motor cortex during movement execution and movement imagery were used to develop subject-dependent models that obtained high classification accuracies thereby indicating the robustness of our classification method. In the third experiment, a generalized classifier-model was developed from the first two experimental data, which was then applied for subject-independent neurofeedback training. Application of this method in new participants showed mean classification accuracy of 63% for movement imagery tasks and 80% for movement execution tasks. These results, and their corresponding offline analysis reported in this study demonstrate that SVM based real-time subject-independent classification of fNIRS signals is feasible. This method has important applications in the field of hemodynamic BCIs, and neuro-rehabilitation where patients can be trained to learn spatio-temporal patterns of healthy brain activity. 相似文献
32.
33.
34.
Ming-Shan Kao Jen-Ho Yang Arun Balasubramaniam Supitchaya Traisaeng Albert Jackson Yang John Jackson Yang Benjamin Prethiviraj Salamon Deron R. Herr Chun-Ming Huang 《Microbial biotechnology》2022,15(7):1984-1994
Infection by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can trigger excessive interleukin (IL)-6 signalling, leading to a myriad of biological effects including a cytokine storm that contributes to multiple organ failure in severe coronavirus disease 2019 (COVID-19). Using a mouse model, we demonstrated that nasal inoculation of nucleocapsid phosphoprotein (NPP) of SARS-CoV-2 increased IL-6 content in bronchoalveolar lavage fluid (BALF). Nasal administration of liquid coco-caprylate/caprate (LCC) onto Staphylococcus epidermidis (S. epidermidis)-colonized mice significantly attenuated NPP-induced IL-6. Furthermore, S. epidermidis-mediated LCC fermentation to generate electricity and butyric acid that promoted bacterial colonization and activated free fatty acid receptor 2 (Ffar2) respectively. Inhibition of Ffar2 impeded the effect of S. epidermidis plus LCC on the reduction of NPP-induced IL-6. Collectively, these results suggest that nasal S. epidermidis is part of the first line of defence in ameliorating a cytokine storm induced by airway infection of SARS-CoV-2. 相似文献
35.
In Vitro Cellular & Developmental Biology - Plant - In vitro culture in combination with aeroponics is observed to be an efficient means for mass propagation of Sarcostemma acidum in the... 相似文献
36.
37.
Nirmaljeet Kaur Prachi Gupta Vikram Saini Sandeep Sherawat Sanjeev Gupta Anita Dua Vinod Kumar Elisha Injeti Ashwani Mittal 《Journal of cellular physiology》2019,234(5):6194-6208
Skeletal muscle atrophy/wasting is associated with impaired protein metabolism in diverse physiological and pathophysiological conditions. Elevated levels of reactive oxygen species (ROS), disturbed redox status, and weakened antioxidant defense system are the major contributing factors toward atrophy. Regulation of protein metabolism by controlling ROS levels and its associated catabolic pathways may help in treating atrophy and related clinical conditions. Although cinnamaldehyde (CNA) enjoys the established status of antioxidant and its role in ROS management is reported, impact of CNA on skeletal muscle atrophy and related pathways is still unexplored. In the current study, the impact of CNA on C2C12 myotubes and the possible protection of cultured cells from H 2O 2-induced atrophy is examined. Myotubes were treated with H 2O 2 in the presence and absence of CNA and the changes in the antioxidative, proteolytic systems, and mitochondrial functions were scored. Morphological analysis showed significant protective effects of CNA on length, diameter, and nuclei fusion index of myotubes. The evaluation of biochemical markers of atrophy; creatine kinase, lactate dehydrogenase, succinate dehydrogenase along with the study of muscle-specific structural protein (i.e., myosin heavy chain-fast [MHCf] type) showed significant protection of proteins by CNA. CNA pretreatment not only checked the activation of proteolytic systems (ubiquitin-proteasome E3-ligases [MuRF1/Atrogin1]), autophagy [Beclin1/LC3B], cathepsin L, calpain, caspase), but also prevented any alteration in the activities of antioxidative defense enzymes (catalase, glutathione- S-transferase, glutathione-peroxidase, superoxide dismutase, glutathione reductase). The results suggest that CNA protects myotubes from H 2O 2-induced atrophy by inhibiting/resisting the amendments in proteolytic systems and maintains cellular redox-balance. 相似文献
38.
Morteza Mahdavi Mohammadreza Nassiri Mohammad Mahdi Kooshyar Masoume Vakili-Azghandi Amir Avan Ryan Sandry Suja Pillai Alfred King-yin Lam Vinod Gopalan 《Journal of cellular physiology》2019,234(5):5741-5750
The most important cause of developing hereditary breast cancer is germline mutations occurring in breast cancer (BCs) susceptibility genes, for example, BRCA1, BRCA2, TP53, CHEK2, PTEN, ATM, and PPM1D. Many BC susceptibility genes can be grouped into two classes, high- and low-penetrance genes, each of which interact with multiple genes and environmental factors. However, the penetrance of genes can also be represented by a spectrum, which ranges between high and low. Two of the most common susceptibility genes are BRCA1 and BRCA2, which perform vital cellular functions for repair of homologous DNA. Loss of heterozygosity accompanied by hereditary mutations in BRCA1 or BRCA2 increases chromosomal instability and the likelihood of cancer, as well as playing a key role in stimulating malignant transformation. With regard to pathological features, familial breast cancers caused by BRCA1 mutations usually differ from those caused by BRCA2 mutations and nonfamilial BCs. It is essential to acquire an understanding of these pathological features along with the genetic history of the patient to offer an individualized treatment. Germline mutations in BRCA1 and BRCA2 genes are the main genetic and inherited factors for breast and ovarian cancer. In fact, these mutations are very important in developing early onset and increasing the risk of familial breast and ovarian cancer and responsible for 90% of hereditary BC cases. Therefore, according to the conducted studies, screening of BRCA1 and BRCA2 genes is recommended as an important marker for early detection of all patients with breast or ovarian cancer risk with family history of the disease. In this review, we summarize the role of hereditary genes, mainly BRCA1 and BRCA2, in BC. 相似文献
39.
Gerardo Abbandonato Barbara Storti Ilaria Tonazzini Martin Stöckl Vinod Subramaniam Costanza Montis Riccardo Nifosì Marco Cecchini Giovanni Signore Ranieri Bizzarri 《Biophysical journal》2019,116(3):477-486
The plasma membrane of cells has a complex architecture based on the bidimensional liquid-crystalline bilayer arrangement of phospho- and sphingolipids, which in turn embeds several proteins and is connected to the cytoskeleton. Several studies highlight the spatial membrane organization into more ordered (Lo or lipid raft) and more disordered (Ld) domains. We here report on a fluorescent analog of the green fluorescent protein chromophore that, when conjugated to a phospholipid, enables the quantification of the Lo and Ld domains in living cells on account of its large fluorescence lifetime variation in the two phases. The domain composition is straightforwardly obtained by the phasor approach to confocal fluorescence lifetime imaging, a graphical method that does not require global fitting of the fluorescence decay in every spatial position of the sample. Our imaging strategy was applied to recover the domain composition in human oligodendrocytes at rest and under treatment with galactosylsphingosine (psychosine). Exogenous psychosine administration recapitulates many of the molecular fingerprints of a severe neurological disease, globoid cell leukodystrophy, better known as Krabbe disease. We found out that psychosine progressively destabilizes plasma membrane, as witnessed by a shrinking of the Lo fraction. The unchanged levels of galactosyl ceramidase, i.e., the enzyme lacking in Krabbe disease, upon psychosine treatment suggest that psychosine alters the plasma membrane structure by direct physical effect, as also recently demonstrated in model membranes. 相似文献
40.
Ralf Buettner Le Xuan Truong Nguyen Bijender Kumar Corey Morales Chao Liu Lisa S. Chen Tea Pemovska Timothy W. Synold Joycelynne Palmer Ryan Thompson Ling Li Dinh Hoa Hoang Bin Zhang Lucy Ghoda Claudia Kowolik Mika Kontro Calum Leitch Krister Wennerberg Xiaochun Yu Ching-Cheng Chen David Horne Varsha Gandhi Vinod Pullarkat Guido Marcucci Steven T. Rosen 《Journal of cellular physiology》2019,234(9):16295-16303