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We examined the biodiversity of bacteria associated with oyster-shell waste during a 1-year storage period using 16S ribosomal DNA analysis. Temperature variation and structural changes of oyster shell were observed during storage. Initial and final temperatures were at 16-17 degrees C, but a high temperature of about 60 degrees C was recorded after approximately 6 months of storage. The crystal structure and nanograin of the oyster shell surface were sharp and large in size initially and became gradually blunter and smaller over time. Phylogenetic analysis revealed that Firmicutes were dominant in the oyster-shell waste initially, during the high-temperature stage, and after 1 year of storage (making up >65% of the biodiversity at all three sampling times). Bacillus licheniformis was presumed as the predominate Firmicutes present. These bacteria are likely to have important roles in the biodegradation of oyster shell. 相似文献
874.
Lian Hua Luo Pil-Soo Seo Jeong-Woo Seo Sun-Yeon Heo Dae-Hyuk Kim Chul Ho Kim 《Biotechnology letters》2009,31(12):1867-1871
To investigate the effect of cellular fatty acids composition on ethanol tolerance in Escherichia coli, we overexpressed either des, encoding fatty acid desaturase from Bacillus subtilis, or fabA, encoding β-hydroxydecanoyl thio-ester dehydrase from E. coli, or both genes together, into E. coli. Recombinant E. coli harboring fabA had elevated tolerance against ethanol compared to wild type strain. In contrast, des decreased resistance to ethanol. Co-expression of both genes together complemented ethanol tolerance of E. coli. This result indicates how to engineer bacterial strains to be resistant to higher concentrations of ethanol. 相似文献
875.
Moon Her Sung-Il Kang Dong-Hee Cho Yun-Sang Cho In-Yeong Hwang Young-Ran Heo Suk-Chan Jung Han-Sang Yoo 《BMC microbiology》2009,9(1):230
Background
A Brucella eradication program has been executed in Korea. To effectively prevent and control brucellosis, a molecular method for genetic identification and epidemiological trace-back must be established. As part of that, the MLVA typing assay was evaluated and applied to B. abortus isolates for analyzing the characteristics of the regional distribution and relationships of foreign isolates. 相似文献876.
Y-R Heo K Claycombe B H Jones P Wright G E Truett M Zemel W Banz M Maher N Moustaid-Moussa 《Hormones et métabolisme》2002,34(11-12):686-690
Leptin is an adipocyte-secreted hormone that binds hypothalamic receptors and potently decreases food intake. Leptin receptor defects in homozygous mutant Zucker fatty ( fa/fa) rats lead to massive obesity, hyperphagia, decreased energy expenditure, and insulin resistance, while the phenotype of heterozygous ( Fa/fa) lean rats lies between lean ( Fa/Fa) and obese ( fa/fa) rats. Whether heterezygotes exhibit specific changes in lipid metabolism in a diet-responsive manner is not clear. Thus, the specific aim of this study was to test whether the presence of one fa allele modulates lipid metabolism and leptin, and whether these effects are exacerbated by high-fat diet. We demonstrate that the presence of one fa allele significantly increases lipogenesis in adipose tissue assessed by glycerol-3-phosphate dehydrogenase (GPDH) and fatty acid synthase (FAS) activities. FAS is more responsive to high-fat diets than GPDH in Fa/fa rats. Adipose tissue leptin levels are significantly higher in fat pads of Fa/fa compared to Fa/Fa rats. Moreover, Fa/fa rats fed high-fat diet show an additional two-fold increase in leptin levels compared to wild type rats on the same diet. Collectively, these results indicate that the presence of one fa allele increase adipocyte lipogenic enzyme activities, which results in hyperleptinemia concurrent with increased adiposity. 相似文献
877.
Jiwon Ahn Misun Won Jeong-Hae Choi Yong Sung Kim Cho-Rock Jung Dong-Su Im Mi-Lang Kyun Kyeong Lee Kyung-Bin Song Kyung-Sook Chung 《Apoptosis : an international journal on programmed cell death》2013,18(7):870-881
Shikonin derivatives exert powerful cytotoxic effects, induce apoptosis and escape multidrug resistance in cancer. However, the diverse mechanisms underlying their anticancer activities are not completely understood. Here, we demonstrated that shikonin-induced apoptosis is caused by reactive oxygen species (ROS)-mediated activation of Akt/ASK1/p38 mitogen-activated protein kinase (MAPK) and downregulation of p21Cip1. In the presence of shikonin, inactivation of Akt caused apoptosis signal-regulating kinase 1 (ASK1) dephosphorylation at Ser83, which is associated with ASK1 activation. Shikonin-induced apoptosis was enhanced by inhibition of Akt, whereas overexpression of constitutively active Akt prevented apoptosis through modulating ASK1 phosphorylation. Silencing ASK1 and MKK3/6 by siRNA reduced the activation of MAPK kinases (MKK) 3/6 and p38 MAPK, and apoptosis, respectively. Antioxidant N-acetyl cysteine attenuated ASK1 dephosphorylation and p38 MAPK activation, indicating that shikonin-induced ROS is involved in the activation of Akt/ASK1/p38 pathway. Expression of p21Cip1 was significantly induced in early response, but gradually decreased by prolonged exposure to shikonin. Overexpression of p21Cip1 have kept cells longer in G1 phase and attenuated shikonin-induced apoptosis. Depletion of p21Cip1 facilitated shikonin-induced apoptosis, implying that p21Cip1 delayed shikonin-induced apoptosis via G1 arrest. Immunohistochemistry and in vitro binding assays showed transiently altered localization of p21Cip1 to the cytoplasm by shikonin, which was blocked by Akt inhibition. The cytoplasmic p21Cip1 actually binds to and inhibits the activity of ASK1, regulating the cell cycle progression at G1. These findings suggest that shikonin-induced ROS activated ASK1 by decreasing Ser83 phosphorylation and by dissociation of the negative regulator p21Cip1, leading to p38 MAPK activation, and finally, promoting apoptosis. 相似文献
878.
Won-Kyung Hong Anna Yu Sun-Yeon Heo Baek-Rock Oh Chul Ho Kim Jung-Hoon Sohn Ji-Won Yang Akihiko Kondo Jeong-Woo Seo 《Bioprocess and biosystems engineering》2013,36(7):959-963
The oleaginous microalga Aurantiochytrium sp. KRS101 was cultivated in enzymatic hydrolysates of alkali-pretreated empty palm fruit bunches (EFBs), without prior detoxification process. The maximal levels of lipid and docosahexaenoic acid synthesized were 12.5 and 5.4 g L?1 after cultivation for 36 h. Similar lipid levels were also obtained via simultaneous saccharification and cultivation. The results suggested that EFB is a promising source for production of useful lipids by the microalgal strain. 相似文献
879.
Yunseok Heo Naito Ishimoto Ye-Eun Jeon Ji-Hye Yun Mio Ohki Yuki Anraku Mina Sasaki Shunsuke Kita Hideo Fukuhara Tatsuya Ikuta Kouki Kawakami Asuka Inoue Katsumi Maenaka Jeremy R. H. Tame Weontae Lee Sam-Yong Park 《PLoS biology》2022,20(8)
Galanin is a neuropeptide expressed in the central and peripheral nervous systems, where it regulates various processes including neuroendocrine release, cognition, and nerve regeneration. Three G-protein coupled receptors (GPCRs) for galanin have been discovered, which is the focus of efforts to treat diseases including Alzheimer’s disease, anxiety, and addiction. To understand the basis of the ligand preferences of the receptors and to assist structure-based drug design, we used cryo-electron microscopy (cryo-EM) to solve the molecular structure of GALR2 bound to galanin and a cognate heterotrimeric G-protein, providing a molecular view of the neuropeptide binding site. Mutant proteins were assayed to help reveal the basis of ligand specificity, and structural comparison between the activated GALR2 and inactive hβ2AR was used to relate galanin binding to the movements of transmembrane (TM) helices and the G-protein interface.Galanin is a neuropeptide expressed in the central and peripheral nervous systems, where it regulates various processes including neuroendocrine release, cognition, and nerve regeneration. This cryo-electron microscopy study shows how galanin interacts with one of its three human receptor proteins, GALR2, and reveals the basis of the selectivity of this GPCR for Gq. 相似文献
880.
Yu Jung Sohn Hee Taek Kim Kei‐Anne Baritugo Seo Young Jo Hye Min Song Se Young Park Su Kyeong Park Jiwon Pyo Hyun Gil Cha Hoyong Kim Jeong‐Geol Na Chulhwan Park Jong‐Il Choi Jeong Chan Joo Si Jae Park 《Biotechnology journal》2020,15(6)
Advances in scientific technology in the early twentieth century have facilitated the development of synthetic plastics that are lightweight, rigid, and can be easily molded into a desirable shape without changing their material properties. Thus, plastics become ubiquitous and indispensable materials that are used in various manufacturing sectors, including clothing, automotive, medical, and electronic industries. However, strong physical durability and chemical stability of synthetic plastics, most of which are produced from fossil fuels, hinder their complete degradation when they are improperly discarded after use. In addition, accumulated plastic wastes without degradation have caused severe environmental problems, such as microplastics pollution and plastic islands. Thus, the usage and production of plastics is not free from environmental pollution or resource depletion. In order to lessen the impact of climate change and reduce plastic pollution, it is necessary to understand and address the current plastic life cycles. In this review, “sustainable biopolymers” are suggested as a promising solution to the current plastic crisis. The desired properties of sustainable biopolymers and bio‐based and bio/chemical hybrid technologies for the development of sustainable biopolymers are mainly discussed. 相似文献