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排序方式: 共有1568条查询结果,搜索用时 70 毫秒
1.
An experiment was conducted to investigate the effect of phytase transgenic corn (PTC) on intestinal microflora, and the fate of transgenic DNA and protein in the digesta and tissues of broilers. A total of 160 1-day-old Arbor Acres commercial male broilers were randomly assigned to 20 cages (8 chicks per cage) with 10 cages (replicates) for each treatment. Birds were fed with a diet containing either PTC (54.0% during 1–21 days and 61.0% during 22–42 days) or non-transgenic isogenic control corn (CC) for a duration of 42 days. There were no significant differences (P>0.05) between birds fed with the PTC diets and those fed with the CC diets in the quantities of aerobic bacteria, anaerobic bacteria, colibacillus and lactobacilli, or microbial diversities in the contents of ileum and cecum. Transgenic phyA2 DNA was not detected, but phyA2 protein was detected in the digesta of duodenum and jejunum of broilers fed with the PTC diets. Both transgenic phyA2 DNA and protein fragments were not found in the digesta of the ileum and rectum, heart, liver, kidney, and breast or thigh muscles of broilers fed with the PTC diets. It was concluded that PTC had no adverse effect on the quantity and diversity of gut microorganisms; Transgenic phyA2 DNA or protein was rapidly degraded in the intestinal tract and was not transferred to the tissues of broilers. 相似文献
2.
Wen-feng Xiao Yu-sheng Li Ang Deng Yun-tao Yang Miao He 《Cell biochemistry and function》2020,38(2):122-129
The hedgehog signalling pathway is one of the key regulators of metazoan development, and it plays an important role in the regulation of a variety of developmental and physiological processes. But it is aberrantly activated in many human diseases, including osteoarthritis (OA). In this study, we have reviewed the association of hedgehog signalling pathway in the development and progression of OA and evaluated the efforts to target this pathway for the prevention of OA. Usually in OA, activation of hedgehog induces up-regulation of the expression of hypertrophic markers, including type X collagen, increases production of nitric oxide and prostaglandin E2, several matrix-degrading enzymes including matrix metalloproteinase and a disintegrin and metalloproteinase with thrombospondin motifs in human knee joint cartilage leading to cartilage degeneration, and thus contributes in OA. Targeting hedgehog signalling might be a viable strategy to prevent or treat OA. Chemical inhibitors of hedgehog signalling is promising, but they cause severe side effects. Knockdown of HH gene is not an option for OA treatment in humans because it is not possible to delete HH in larger animals. Efficient knockdown of HH achieved by local delivery of small interfering RNA in future studies utilizing large animal OA models might be a more efficient approach for the prevention of OA. However, it remains a major problem to develop one single scaffold due to the different physiological functions of cartilage and subchondral bones possess. More studies are necessary to identify selective inhibitors for efficiently targeting the hedgehog pathway in clinical conditions. 相似文献
3.
Paulo Eugênio Oliveira Peter Edward Gibbs Ana Angélica Barbosa 《Plant Systematics and Evolution》2004,245(1-2):41-54
We present a survey of moth pollination in woody species of the Cerrado of Central Brazil. Although with the exception of Roupala
montana (which has simple polysepalous flowers arranged in dense cymes) all moth pollinated species in this community have tubular flowers, or a pseudo-tube formed from a single folded petal in Qualea
grandiflora, settling moth flowers (tube less than 15 mm) vs. hawkmoth flowers (tube more than 50 mm) are markedly different in size. Moths visit some 20 woody Cerrado species, but they are probably effective pollinators of only 13 species or ca.14% of the woody taxa studied, and even in these latter species they are often very sparse visitors. Nevertheless, it is notable that moths are pollinators for 21% of the 38 most commonly distributed woody Cerrado species. Moreover, the reproductive efficacy of the studied moth pollinated species was similar to that of species pollinated by other kind of vectors. 相似文献
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Exogenous enzymes can be loaded into nucleated chicken erythrocytes by hypotonic hemolysis. The hemolysed and resealed cells retain the ability to activate transport ions and to survive while circulating in the blood of chickens. It is proposed that these cells may be useful for the investigation of several aspects of cellular biochemistry. 相似文献
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Rui Liu Ting Zhu Tao Yang Zhengyan Yang Ang Ren Liang Shi Jing Zhu Hanshou Yu Mingwen Zhao 《Environmental microbiology》2021,23(2):682-695
Nitric oxide (NO) is an important signalling molecule in stress response of organisms. We previously reported that NO decreases heat stress (HS)-induced ganoderic acid (GA) accumulation in Ganoderma lucidum. To explore the mechanisms by which NO modulates GA biosynthesis under HS, the effect of NO on the reactive oxygen species (ROS) content was examined. The results showed that NO decreased the production of mitochondrial ROS (mitROS) by 60% under HS. Further research revealed that NO reduced the mitROS content by inhibiting aconitase (Acon) activity. The GA content in Acon-silenced (Aconi) strains treated with NO donor did not differ significantly from that in untreated Aconi strains. To study the mechanism by which Acon activity is inhibited, the S-nitrosylation level of Acon was determined. Biotin-switch technology and mass spectrometry analysis were used to show that Acon is S-nitrosylated at the Cys-594 amino acid residue. Substitution of Cys-594 with a Ser, which cannot be S-nitrosylated, abolished the responsiveness of Acon to the NO-induced reduction in its enzymatic activity. These findings demonstrate that NO inhibits Acon activity through S-nitrosylation at Cys-594. In summary, these findings describe mechanism by which NO regulates GA biosynthesis via S-nitrosylation of Acon under HS condition in G. lucidum. 相似文献
9.
Yun-gang Luo Ping Liu Lin Shi Yishan Luo Lei Yi Ang Li Jing Qin Pheng-Ann Heng Defeng Wang 《PloS one》2015,10(9)
Neuroimage registration is crucial for brain morphometric analysis and treatment efficacy evaluation. However, existing advanced registration algorithms such as FLIRT and ANTs are not efficient enough for clinical use. In this paper, a GPU implementation of FLIRT with the correlation ratio (CR) as the similarity metric and a GPU accelerated correlation coefficient (CC) calculation for the symmetric diffeomorphic registration of ANTs have been developed. The comparison with their corresponding original tools shows that our accelerated algorithms can greatly outperform the original algorithm in terms of computational efficiency. This paper demonstrates the great potential of applying these registration tools in clinical applications. 相似文献
10.
Véronique Ollivier Varouna Syvannarath Angèle Gros Amena Butt Stéphane Loyau Martine Jandrot-Perrus Beno?t Ho-Tin-Noé 《PloS one》2014,9(8)
Platelets are not only central actors of hemostasis and thrombosis but also of other processes including inflammation, angiogenesis, and tissue regeneration. Accumulating evidence indicates that these “non classical” functions of platelets do not necessarily rely on their well-known ability to form thrombi upon activation. This suggests the existence of non-thrombotic alternative states of platelets activation. We investigated this possibility through dose-response analysis of thrombin- and collagen-induced changes in platelet phenotype, with regards to morphological and functional markers of platelet activation including shape change, aggregation, P-selectin and phosphatidylserine surface expression, integrin activation, and release of soluble factors. We show that collagen at low dose (0.25 µg/mL) selectively triggers a platelet secretory phenotype characterized by the release of dense- and alpha granule-derived soluble factors without causing any of the other major platelet changes that usually accompany thrombus formation. Using a blocking antibody to glycoprotein VI (GPVI), we further show that this response is mediated by GPVI. Taken together, our results show that platelet activation goes beyond the mechanisms leading to platelet aggregation and also includes alternative platelet phenotypes that might contribute to their thrombus-independent functions. 相似文献