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排序方式: 共有291条查询结果,搜索用时 31 毫秒
51.
Petros Katapodis Vasiliki Christakopoulou Paul Christakopoulos 《World journal of microbiology & biotechnology》2006,22(5):501-506
Summary A 32 central composite experimental design was performed with the aim of optimizing xylanase production by Thermomyces lanuginosus grown on corn cobs in submerged cultures. Xylanase production was first tested on different nitrogen sources (tomato skin,
tomato seed meal, corn steep liquor, meat peptone, bacto-tryptone and yeast extract). Tomato seed meal was the selected substrate
to test the effect of two variables on xylanase production (corn cobs and tomato seed meal concentrations). A second-order
quadratic model and a response surface method showed that the optimum condition for xylanase production was corn cobs 4.6%
(w/v) and tomato seed meal 2.1% (w/v). The optimum conditions found were transferred to 7-l bioreactors, where activities
as high as 1630 U/ml were obtained. 相似文献
52.
Anastasios Papalazarou Mary Yannakoulia Stavros A. Kavouras Vasiliki Komesidou George Dimitriadis Alexandros Papakonstantinou Labros S. Sidossis 《Obesity (Silver Spring, Md.)》2010,18(7):1348-1353
The present study was designed to evaluate the 3 year effects of a lifestyle intervention on weight loss and maintenance, dietary, and physical activity habits and eating behavior of patients following vertical banded gastroplasty (VBG). Thirty severely obese female volunteers were included in the study and they were randomly assigned to one of two intervention groups: usual care (UC) or lifestyle intervention (LS) group. Patients were followed for 3 years postoperatively. Outcome measures included weight loss, dietary habits, physical activity level (PAL), and eating behavior changes. Weight was significantly lower in the LS group after 12 months (84.4 ± 3.9 kg vs. 98.4 ± 4.4 kg, P < 0.05), 24 months (83.0 ± 3.3 vs. 101.9 ± 5.3 kg, P < 0.05), and 36 months following surgery (84.2 ± 3.3 vs. 102.5 ± 3.5 kg, P < 0.05). Repeated measures ANOVA revealed significant differences between the two groups overall and at specific time points for the PAL and TV viewing. With regard to eating behavior, the LS group scored significantly better in total Dutch Eating Behavior Questionnaire (DEBQ), Restraint Eating and External Eating scales at all postoperative time points. Similarly, significant differences were found between the two groups in dietary intake. These findings outline the importance of lifestyle intervention on weight loss and maintenance following bariatric surgery. The favorable effects of lifestyle intervention may be through adoption of healthier eating behaviors and increased physical activity. 相似文献
53.
Christodoulou V Messaritakis I Svirinaki E Tsatsanis C Antoniou M 《Experimental parasitology》2011,(3):279-284
Although macrophages have a microbicidal role in the immune system they themselves can be infected by pathogens. Often a simultaneous infection by more than one microbe may occur in a single cell. This is the first report of coinfection of macrophages with Toxoplasma gondii and Leishmania infantum, in vitro and in vivo. L. infantum does not cause severe disease in mice but T. gondii, RH strain, is lethal. Cell culture studies using THP-1 macrophages dually infected in vitro revealed that 4.3% harbored both parasites 24 h after infection. When mice were infected with both parasites on the same day 7.3% of the infected cells carried both parasites 7 days later. Yet, if mice were first infected with L. infantum and then with Toxoplasma (5 days post-infection) 18.7% of the macrophages hosted either parasite but concomitant infection could not be found and mice, already harboring L. infantum, survived Toxoplasma’s lethal effect. 相似文献
54.
Panagiotou V Love KR Jiang B Nett J Stadheim T Love JC 《Applied and environmental microbiology》2011,77(9):3154-3156
The selection of highly productive cell lines remains a key step for manufacturing therapeutic proteins. Microengraving was used to screen chemically mutagenized populations of Pichia pastoris for increased production of an Fc fragment. Clones retrieved following three rounds of mutagenesis yielded titers 2.65-fold greater than those of the parental strain. 相似文献
55.
Amillis S Kosti V Pantazopoulou A Mikros E Diallinas G 《Journal of molecular biology》2011,411(3):567-39605
Earlier, we identified mutations in the first transmembrane segment (TMS1) of UapA, a uric acid-xanthine transporter in Aspergillus nidulans, that affect its turnover and subcellular localization. Here, we use one of these mutations (H86D) and a novel mutation (I74D) as well as genetic suppressors of them, to show that TMS1 is a key domain for proper folding, trafficking and turnover. Kinetic analysis of mutants further revealed that partial misfolding and deficient trafficking of UapA does not affect its affinity for xanthine transport, but reduces that of uric acid and confers a degree of promiscuity towards the binding of other purines. This result strengthens the idea that subtle interactions among domains not directly involved in substrate binding refine the selectivity of UapA. Characterization of second-site suppressors of H86D revealed a genetic interaction of TMS1 with TMS3, the latter segment shown for the first time to be important for UapA function. Systematic mutational analysis of polar and conserved residues in TMS3 showed that Ser154 is crucial for UapA transport activity. Our results are in agreement with a topological model of UapA built on the recently published structure of UraA, a bacterial homolog of UapA. 相似文献
56.
A computational study of the Warburg effect identifies metabolic targets inhibiting
cancer migration 下载免费PDF全文
57.
58.
Sylvia Zakkak Maria Chatzaki Nikos Karamalis Vasiliki Kati 《Journal of Insect Conservation》2014,18(4):599-611
Agricultural land abandonment is a major conservation issue when it comes to remote Mediterranean mountainous ecosystems. Although its impact on taxa such as birds or butterflies is well known, knowledge remains poor for less studied invertebrate taxa such as spiders. We sampled ground spiders (Gnaphosidae, Liocranidae, Miturgidae and Corrinidae) in 20 randomly selected sites (1 km × 1 km; 15 pitfall traps) that well depicted a land abandonment gradient, in terms of four forest encroachment classes. Our results showed a negative effect of land abandonment on ground spider species richness and diversity (Simpson index), pinpointing that forested habitats with more than 75 % woody vegetation cover are relatively poor. We also provide evidence for the beneficial role of low intensity grazing (0.4–4 livestock units/km2) for ground spider abundance. Community analysis revealed four distinct clusters of co-occurring species, while Generalized Linear Models at cluster and species level showed the definitive role of forest encroachment, and secondarily of other environmental factors such as humidity, elevation and longitude, in regulating species distribution patterns. Conservation measures for ground spider diversity maintenance should focus on promoting traditional agricultural practices, including small-scale cultivation and mild livestock grazing in order to preserve open and semi-open rural mosaics. 相似文献
59.
Y T Pan G P Kaushal G Papandreou B Ganem A D Elbein 《The Journal of biological chemistry》1992,267(12):8313-8318
The amidrazone of D-mannonolactam (see compound 5, Fig. 1) was synthesized chemically as a mimic of the mannopyranosyl cation and tested as a potential inhibitor of mannosidases. In this study compound 5 is shown to be a more general mannosidase inhibitor than other currently known compounds and exhibits properties not previously observed with any other mannosidase inhibitors. Thus D-mannonolactam amidrazone not only inhibits the Golgi mannosidase I (IC50 = 4 microM) and mannosidase II (IC50 = 90-100 nM), but it is the first inhibitor that has been shown to be a potent inhibitor of the soluble or endoplasmic reticulum alpha-mannosidase (IC50 = 1 microM). This compound also inhibited the aryl-mannosidases regardless of anomeric configuration although it was much more effective on enzymes recognizing alpha-linked mannose, i.e. jack bean and mung bean alpha-mannosidases (IC50 = 400 nM) as compared with fungal beta-mannosidase (IC50 = 150 microM). Mannonoamidrazone was tested in animal cell cultures using influenza virus-infected Madin-Darby canine kidney cells as a model system, and was found to prevent almost completely the formation of complex types of N-linked oligosaccharides with the formation of about equal amounts of Man9(GlcNAc)2 and Man8(GlcNAc)2 structures. Thus D-mannonolactam amidrazone is a potent but broad spectrum mannosidase inhibitor whose structure and properties should provide valuable insight into the design of other useful glycosidase inhibitors. 相似文献
60.
Vasiliki?Chondrou Eleana?F.?Stavrou Georgios?Markopoulos Alexandra?Kouraklis-Symeonidis Vasilios?Fotopoulos Argiris?Symeonidis Efthymia?Vlachaki Panagiota?Chalkia George?P.?Patrinos Adamantia?Papachatzopoulou Argyro?SgourouEmail author 《Human genomics》2018,12(1):45