全文获取类型
收费全文 | 945篇 |
免费 | 68篇 |
国内免费 | 5篇 |
出版年
2023年 | 6篇 |
2022年 | 4篇 |
2021年 | 17篇 |
2020年 | 21篇 |
2019年 | 11篇 |
2018年 | 28篇 |
2017年 | 24篇 |
2016年 | 30篇 |
2015年 | 54篇 |
2014年 | 66篇 |
2013年 | 71篇 |
2012年 | 83篇 |
2011年 | 55篇 |
2010年 | 50篇 |
2009年 | 34篇 |
2008年 | 60篇 |
2007年 | 46篇 |
2006年 | 57篇 |
2005年 | 40篇 |
2004年 | 48篇 |
2003年 | 48篇 |
2002年 | 23篇 |
2001年 | 26篇 |
2000年 | 19篇 |
1999年 | 19篇 |
1998年 | 6篇 |
1997年 | 7篇 |
1996年 | 5篇 |
1995年 | 5篇 |
1994年 | 5篇 |
1993年 | 2篇 |
1992年 | 9篇 |
1991年 | 9篇 |
1990年 | 2篇 |
1989年 | 3篇 |
1988年 | 6篇 |
1987年 | 1篇 |
1986年 | 3篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1981年 | 4篇 |
1980年 | 1篇 |
1979年 | 3篇 |
1978年 | 3篇 |
1975年 | 1篇 |
排序方式: 共有1018条查询结果,搜索用时 15 毫秒
991.
Yoosik Youm Junsol Kim Seyul Kwak Jeanyung Chey 《Proceedings. Biological sciences / The Royal Society》2021,288(1944)
To avoid polarization and maintain small-worldness in society, people who act as attitudinal brokers are critical. These people maintain social ties with people who have dissimilar and even incompatible attitudes. Based on resting-state functional magnetic resonance imaging (n = 139) and the complete social networks from two Korean villages (n = 1508), we investigated the individual-level neural capacity and social-level structural opportunity for attitudinal brokerage regarding gender role attitudes. First, using a connectome-based predictive model, we successfully identified the brain functional connectivity that predicts attitudinal diversity of respondents'' social network members. Brain regions that contributed most to the prediction included mentalizing regions known to be recruited in reading and understanding others’ belief states. This result was corroborated by leave-one-out cross-validation, fivefold cross-validation and external validation where the brain connectivity identified in one village was used to predict the attitudinal diversity in another independent village. Second, the association between functional connectivity and attitudinal diversity of social network members was contingent on a specific position in a social network, namely, the structural brokerage position where people have ties with two people who are not otherwise connected. 相似文献
992.
K. H. Jung S. S. Kwak S. W. Kim C. Y. Choi G. S. Heo J. R. Liu 《Biotechnology Techniques》1992,6(4):305-308
Summary To produce economically important indole alkaloids by cell culture, we have selected protoclones ofCatharanthus roseus for high yields of catharanthine and ajmalicine. Protoplasts were enzymatically isolated from suspension-cultured cells.
Protoclone VPC-10 produced catharanthine at 5.9 μg/g fresh wt of cells after 10 days of culture, although the original cell
line did not produce it at a level detectable by HPLC. Under the same conditions, protoclone VPC-15 produced ajmalicine at
133.6 μg/g, which was about 3 times the productivity of the original cell line. In addition, the indole alkaloids were qualitatively
confirmed by LC-MS. 相似文献
993.
Sungjong Kwak Elana Brief Denis Langlais Neil Kitson Michel Lafleur Jenifer Thewalt 《生物化学与生物物理学报:生物膜》2012,1818(5):1410-1419
Ethanol is used in a variety of topical products. It is known to enhance the permeability of the skin by altering the ability of the stratum corneum (SC) intercellular membranes to form an effective barrier. In addition, ethanol and other alcohols are key components of antiseptic gels currently used for hand wash. Using infrared and deuterium NMR spectroscopy as well as calorimetry, we have investigated the effect of ethanol on a model membrane composed of lipids representing the three classes of SC lipids, an equimolar mixture of N-palmitoylsphingosine (ceramide), palmitic acid and cholesterol. Ethanol is found to influence the membrane in a dose dependent manner, disrupting packing and increasing lipid motion at low concentrations and selectively extracting lipids at moderate concentrations. 相似文献
994.
Brenda R. Kwak Paolo Silacci Nikos Stergiopulos Daniel Hayoz Paolo Meda 《Cell communication & adhesion》2005,12(5):261-270
Hemodynamic forces play a critical role in atherogenesis, as evidenced by the focal pattern of development of atherosclerotic lesions. Whereas disturbed flow in the branches and curved regions of large arteries is proatherogenic, laminar flow in the straight parts of vessels is atheroprotective. In addition, hypertension and age-related changes in arterial stiffness are important risk factors of the disease. Hemodynamic forces induce various changes in the structure and function of vascular endothelium, many of which reflect alterations in gene expression. Endothelial cells are linked by gap junctions, which facilitate the propagation of electrical and chemical signals along the vascular wall. Using an in vitro perfusion system, we investigated the effects of pulsed unidirectional and oscillatory flows in combination with different levels of hydrostatic pressure and circumferential stretch on the expression of Cx43 in endothelial cells. Our results show that shear stress and circumferential stretch, but not pressure, modulate the expression of Cx43. In view of the distribution of this protein along the vascular tree, our findings provide new insights into the role of mechanical forces on gap junctional communication in regions prone to the development of atherosclerosis. 相似文献
995.
996.
There is rapidly growing interest in the human microbiome because of its implication in metabolic disorders and inflammatory diseases. Consequently, understanding the biology of short chain fatty acids and their receptors has become very important for identifying novel therapeutic avenues. GPR41 and GPR43 have been recognized as the cognate receptors for SCFAs and their roles in metabolism and inflammation have drawn much attention in recent years. GPR43 is highly expressed on immune cells and has been suggested to play a role in inflammatory diseases such as inflammatory bowel disease. Both GPR41 and GPR43 have been implicated in diabetes and obesity via the regulation of adipose tissue and gastrointestinal hormones. So far, many studies have provided contradictory results, and therefore further research is required to validate these receptors as drug targets. We will also discuss the synthetic modulators of GPR41 and GPR43 that are critical to understanding the functions of these receptors. [BMB Reports 2014; 47(3): 173-178] 相似文献
997.
Seon-Yeong Kwak Hyun Jung Lee Jin-Kyoung Yang Eun Jig Lee MiRan Seo Yoon-Sik Lee 《Amino acids》2014,46(12):2777-2785
Caffeic acid (CA) is one of the antioxidants found in plants, which protects vascular cells against vascular injuries from oxidative stress. In our previous study, caffeoyl-prolyl-histidine amide (CA-L-Pro-L-His-NH2; CA-PH; a CA derivative) was synthesized, which exhibited a strong antioxidant activity with sufficient stability. In this study, we investigated the role of CA-PH in vascular smooth muscle cells (VSMCs) and confirmed the enhanced antioxidant activity of CA-PH compared with that of CA. In in vitro tube assays, CA-PH showed a higher free-radical-scavenging activity and lipid-peroxidation-inhibition activity than those of CA. In VSMCs, CA-PH significantly reduced hydrogen peroxide-induced ROS generation and increased the expression of heme oxygenase-1. Moreover, CA-PH effectively inhibited the platelet-derived growth factor-induced cellular proliferation of VSMCs, which was confirmed by a decrease in the expression of the proliferating cell nuclear antigen and the phosphorylation of Akt. 相似文献
998.
Jae Kwak Alan Willse George Preti Kunio Yamazaki Gary K. Beauchamp 《Proceedings. Biological sciences / The Royal Society》2010,277(1693):2417-2425
Mice can discriminate between chemosignals of individuals based solely on genetic differences confined to the major histocompatibility complex (MHC). Two different sets of compounds have been suggested: volatile compounds and non-volatile peptides. Here, we focus on volatiles and review a number of publications that have identified MHC-regulated compounds in inbred laboratory mice. Surprisingly, there is little agreement among different studies as to the identity of these compounds. One recent approach to specifying MHC-regulated compounds is to study volatile urinary profiles in mouse strains with varying MHC types, genetic backgrounds and different diets. An unexpected finding from these studies is that the concentrations of numerous compounds are influenced by interactions among these variables. As a result, only a few compounds can be identified that are consistently regulated by MHC variation alone. Nevertheless, since trained animals are readily able to discriminate the MHC differences, it is apparent that chemical studies are somehow missing important information underlying mouse recognition of MHC odourtypes. To make progress in this area, we propose a focus on the search for behaviourally relevant odourants rather than a random search for volatiles that are regulated by MHC variation. Furthermore, there is a need to consider a ‘combinatorial odour recognition’ code whereby patterns of volatile metabolites (the basis for odours) specify MHC odourtypes. 相似文献
999.
A Biragyn M Surenhu D Yang P A Ruffini B A Haines E Klyushnenkova J J Oppenheim L W Kwak 《Journal of immunology (Baltimore, Md. : 1950)》2001,167(11):6644-6653
Chemokine receptors are differentially expressed on immature and mature dendritic cells (DC). Herein, we demonstrate for the first time that murine antimicrobial peptides beta-defensins 2 and 3 bind murine CCR6, similarly to inflammatory chemokine macrophage-inflammatory protein 3alpha, and they chemoattract bone marrow-derived immature, but not mature DC. Using various chemokines or defensins fused with nonimmunogenic tumor Ags, we studied their capacity to delivery Ags to subsets of immune cells to elicit antitumor immunity. We demonstrate that DNA immunizations with fusion constructs with beta-defensin 2 or inflammatory chemokines that target immature DC, but not homeostatic chemokines secondary lymphoid tissue chemokine, CCL21, or stromal cell-derived factor 1, CXCL12, which chemoattract mature DC, elicit humoral, protective, and therapeutic immunity against two different syngeneic lymphomas. 相似文献
1000.
Daehwan Kim Jin-Se Kim In-Yong Park Hee-Jin Kwak Dong Ho Lee 《Animal cells and systems.》2016,20(1):48-51
A novel chitinase gene, EaChi, and its expression pattern from the earthworm, E. andrei are demonstrated. Based on a deduced amino acid sequence, in EaChi, two specific domains for GH family 18 are well conserved with two essential amino acid residues for enzyme activity. The phylogenetic analysis shows that earthworm chitinase, EaChi, is evolutionarily close to other lophotrochozoan chitinases. The expression pattern analysis of EaChi indicates that the major expression is localized at intestinal epithelium and epidermis, possibly suggesting that the prime functions of the chitinase activity could be related to not only digestive process but also self-defending immunity as a biochemical barrier to protect the invasion of chitin-containing pathogens, including fungi, nematodes and protozoa. 相似文献