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161.
International Journal of Peptide Research and Therapeutics - Bioactive peptides have emerged as promising therapeutic alternatives in pharmaceutical industry, especially to fight cancer. Here we...  相似文献   
162.
Zhang  Peng  Yang  Chao  Ao  Yulong 《Cluster computing》2021,24(2):935-951
Cluster Computing - In large-scale atmospheric simulations, microphysics parameterization often takes a large portion of simulation time and usually consists of dozens of parameterization schemes....  相似文献   
163.
Nie  Hongtao  Zheng  Mengge  Wang  Zhengxing  Xu  Qiaoyue  Yin  Zhihui  Zhang  Yanming  Yan  Xiwu 《Functional & integrative genomics》2021,21(3-4):341-353
Functional & Integrative Genomics - Growth is one of the most important traits of aquaculture breeding programs. Understanding the mechanisms underlying growth differences between individuals...  相似文献   
164.
You  Tingting  Gao  Yukun  Chen  Huaxiang  Yin  Penggang 《Plasmonics (Norwell, Mass.)》2021,16(4):1231-1239
Plasmonics - Tunable local surface plasmon resonance (LSPR) enhancement properties of cavity-nanoparticle scaffold-based clusters were investigated via finite-difference time-domain (FDTD)...  相似文献   
165.
目的探讨大连地区分泌型和非分泌型母亲哺乳期间母乳菌群的主要差异。方法于大连市妇幼保健院纳入42名志愿者产妇,收集其产后第6天的母乳样本。提取母乳样本DNA,并对包含rs601338和rs1047781单核酸位点多态性(SNP)的片段用聚合酶链式反应(polymerase chain reaction,PCR)检测并加以测序,以检测受试母亲岩藻糖基转移酶2基因(FUT2)的类型。采用16S rRNA高通量测序法对不同母乳样本中微生物的多样性进行分析,并且对不同母乳样本中的微生物丰度及类型展开探讨。结果母亲分泌型分布情况分析:42名志愿者中,36名母亲是分泌型,6名母亲是非分泌型。母乳菌群多样性分析:分泌型与非分泌型组母亲母乳菌群比较,发现反映组内差异的Alpha多样性指数(包括Ace、Chao1以及Shannon等)在2组间差异无统计学意义;通过使用主坐标分析,发现分泌型组和非分泌型组的距离相对较远,母乳菌群组内菌群结构类似,组间差异性较显著,说明母乳中的蛋白核心岩藻糖基化水平可明显改变母乳中菌群结构。乳汁菌群物种构成分析:从门水平分析,变形菌门与厚壁菌门为主要优势菌;从属水平分析,2组母乳菌群中的双歧杆菌属丰度差异较显著。相关性分析:分泌型母乳的菌群中相关基因的表达更强,说明分泌型母乳对菌群基因的表达有促进作用。结论母乳菌群构成在一定程度上受到母体FUT2基因类型,即母亲分泌型和非分泌型的影响。  相似文献   
166.
167.
Shells of calcifying foraminifera play a major role in marine biogeochemical cycles; fossil shells form important archives for paleoenvironment reconstruction. Despite their importance in many Earth science disciplines, there is still little consensus on foraminiferal shell mineralization. Geochemical, biochemical, and physiological studies showed that foraminiferal shell formation might take place through various and diverse mineralization mechanisms.In this study, we contribute to benthic foraminiferal shell calcification through deciphering crystallite organization within the shells. We base our conclusions on results gained from electron backscattered diffraction (EBSD) measurements and describe microstructure/texture characteristics within the laminated shell walls of the benthic, symbiontic foraminifera: Ammonia tepida, Amphistegina lobifera, Amphistegina lessonii. We highlight crystallite assembly patterns obtained on differently oriented cuts and discuss crystallite sizes, morphologies, interlinkages, orientations, and co-orientation strengths.We show that: (i) crystals within benthic foraminiferal shells are mesocrystals, (ii) have dendritic-fractal morphologies and (iii) interdigitate strongly. Based on crystal size, we (iv) differentiate between the two layers that comprise the shells and demonstrate that (v) crystals in the septa have different assemblies relative to those in the shell walls. We highlight that (vi) at junctions of different shell elements the axis of crystal orientation jumps abruptly such that their assembly in EBSD maps has a bimodal distribution. We prove (vii) extensive twin-formation within foraminiferal calcite; we demonstrate (viii) the presence of two twin modes: 60°/[0 0 1] and 77°/~[6 –6 1] and visualize their distributions within the shells.In a broader perspective, we draw conclusions on processes that lead to the observed microstructure/texture patterns.  相似文献   
168.
Curcumin exhibits anti‐inflammatory and antioxidant activities. We investigated the protective effects of curcumin in a renal injury rat model under dry‐heat conditions. We divided Sprague‐Dawley rats into four groups: dry‐heat 0‐ (normal temperature control group), 50‐, 100‐, and 150‐minute groups. Each group was divided into five subgroups (n = 10): normal saline (NS), sodium carboxymethylcellulose (CMCNa), and curcumin pretreated low, medium, and high‐dose (50, 100, and 200 mg/kg, respectively) groups. Compared to the normal temperature group, serum creatinine, blood urea nitrogen, urinary kidney injury molecule‐1, and neutrophil gelatinase‐associated load changes in lipoprotein (NGAL) levels were significantly increased in the dry‐heat environment group (P < .05); inducible nitric oxide synthase (iNOS) and cyclooxygenase‐2 (COX‐2) expression and malondialdehyde (MDA) and related inflammatory factor levels were increased in the kidney tissue. Superoxide dismutase (SOD) and catalase (CAT) levels were decreased. However, following all curcumin pretreatment, the serum levels of kidney injury indicators and NGAL were decreased in the urine compared to those in the NS and CMCNa groups (P < .05), whereas renal SOD and CAT activities were increased and MDA was decreased (P < .05). Renal tissues of the 150‐minute group showed obvious pathological changes. Compared to the NS group, pathological changes in the renal tissues of the 100‐ and 200‐mg/kg curcumin groups were significantly reduced. Furthermore, iNOS and COX‐2 expression and inflammatory factor levels were decreased after curcumin treatment. Curcumin exerted renoprotective effects that were likely mediated by its antioxidant and anti‐inflammatory effects in a dry‐heat environment rat model.  相似文献   
169.
矿物元素在畜禽生长发育、新陈代谢、神经活动、免疫功能、内分泌等几乎所有的生命活动过程中都发挥着重要的生理作用,分为钙、磷、钠、镁等常量元素和铁、锰、钴、铜等微量元素。某种矿物元素摄入不足或在体内过量蓄积、矿物元素间比例失调,都将引起严重后果。随着畜禽养殖业的集约化规模化发展,饲用矿物元素用量迅速增加,但存在不合理使用的情况,造成了资源浪费和环境污染。因此,在满足畜禽营养需要量的前提下,合理地使用矿物元素剂型及剂量,实现降低矿物元素经畜禽粪污向环境中的排放量,不仅利于集约化畜禽养殖业的发展,同时也能有效降低畜禽粪污中的重金属含量,为种植业提供优良的有机肥来源,维护生态系统的平衡,促进种植业和养殖业的可持续健康发展。基于此,以畜禽体内含量最高的常量元素钙磷和微量元素为切入点,介绍了饲用矿物元素的应用现状、畜禽矿物元素基础需要量及合适的添加范围,着重综述了新型饲用微量元素的开发与应用进展,并探讨了矿物元素动态饲喂模式的可行性及有效性,以期为合理利用矿物元素资源及进一步解决全球生态农业研究的畜禽矿物元素导致的环境污染提供参考。  相似文献   
170.
We investigated the performance of small-caliber polyurethane (PU) small-diameter vascular prosthesis generated using the electrospinning technique. PU was electrospun into small-diameter, small-caliber tubular scaffolds for potential application as vascular grafts. We investigated the effects of electrospinning conditions (solution concentration, mandrel rotation speed) on the microstructure and porosity of the scaffolds for the purpose of preparing scaffolds with optimum microstructures and properties. We evaluated the mechanical properties of the scaffolds by tensile tests and the cytotoxicity of the PU small-diameter, small-caliber PU synthetic vascular graft by the MTT assay. The adhesion of endothelial cells to the PU scaffold was characterized by Hoechst staining and fluorescence microscopy, and we measured endothelial cell proliferation on the PU scaffold by the CCK-8 assay. We analyzed the prosthesis microstructure and endothelial cell morphology using scanning electron microscopy. With increasing PU concentration in the electrospinning solution, the fiber diameter of the vascular graft increased and the porosity decreased. In addition, with increasing electrospinning time, the wall thickness increased and the porosity decreased. We found that regular fiber orientation can be obtained by adjusting the rotation speed of the mandrel. Cell proliferation was not inhibited as the small-caliber PU synthetic vascular grafts showed little cytotoxicity. The endothelial cells had faster adherence to the PU scaffolds than to the PTFE surface during the initial contact. After prolonged cell culture, significantly higher endothelial cell proliferation rate was observed in the PU scaffold groups than the PTFE group. We obtained small-caliber PU vascular grafts with optimal fiber arrangement, excellent mechanical properties, and optimal biocompatibility by optimizing the electrospinning conditions. This study provides in vitro biocompatibility data that is helpful for the clinical application of the PU small-diameter, small-caliber PU vascular grafts.  相似文献   
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