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41.
Min Huang Shengliang Fang Fangbo Cao Jiana Chen Shuanglü Shan Yu Liu Tao Lei Alin Tian Zui Tao Yingbin Zou 《The Annals of applied biology》2020,176(3):308-313
High seed sowing rates have shortened seedling age in conventional machine-transplanted rice, which has become a challenge for intensive rice production in China. This study aimed to test our hypothesis that prolonging seedling age may not lead to reduced yield in machine-transplanted early-season rice under precision sowing. Field experiments were conducted with two cultivars in 2 years to determine the effect of prolonging seedling age on seedling traits, grain yield, and yield attributes in machine-transplanted early-season rice with printed sowing (a new precision sowing method). All tested seedling traits, including height, basal width, leaf and root number, and shoot and root biomass, were significantly increased when seedling age was prolonged from 20 days (a commonly recommended seedling age for conventional machine transplanting) to 30 days. The prolonged seedling age did not significantly affect grain yield, yield components, or biomass production and translocation. These results support our hypothesis and suggest that adopting precision sowing is a feasible way to prolong seedling age of machine-transplanted early-season rice. 相似文献
42.
Veenakumari Kamalanathan Ovidiu Alin Popovici Elijah J. Talamas Prashanth Mohanraj 《Journal of Asia》2018,21(2):571-577
A new scelionine genus Indiscelio Veenakumari, Popovici and Talamas is described from India with type species Indiscelio aulon Veenakumari, Popovici and Talamas. Both sexes are described and imaged. Affinities with morphologically similar genera are discussed. 相似文献
43.
羊草种群生态和演化形态学特性的比较研究 总被引:17,自引:0,他引:17
对单优种羊草种群的演普及演化规律的分析表明,黑钙土型羊草植物体结构简单,盐碱土型羊草结构复杂,演化出进化程度较高的通气组织、保护组织、薄壁组织及输导组织等.研究结果表明,不同土壤型羊草具有明显的种内差异. 相似文献
44.
The primary structure of the class Mu glutathione transferase 4-4 from rat liver was determined. The structural data characterize a class Mu protein within an enzyme family for which three classes have been distinguished (Alpha, Mu, Pi). The structure was determined by analysis of peptides obtained after treatment with trypsin. Glu-specific protease and CNBr. The protein is composed of two identical subunits, each with 217 amino acid residues. No evidence for microheterogeneity or for the presence of modified residues was encountered. The primary structure was found to be strictly homologous with corresponding parts in known regions of other class Mu enzymes of rat, mouse, human and bovine origin. Relationships to the cytosolic enzyme of other classes (Pi and Alpha) are considerably more distant. A comparison with the entire chain of the class Alpha subunit 1 from rat liver was carried out by three methods, alignment of amino acid sequences, correlation of hydrophilicity plots and predictions of secondary structures. All methods reveal weak similarities but also large differences. The overall positional identity is only 26%. Combined, the results establish the first complete class Mu structure, show distant inter-class relationships, and relate subunit 4 (class Mu) and subunit 1 (class Alpha) in a family of enzymes rather than in a group of isoenzymes. 相似文献
45.
Single-step purification and h.p.l.c. analysis of glutathione transferase 8-8 in rat tissues. 总被引:1,自引:1,他引:0
D J Meyer E Lalor B Coles A Kispert P Alin B Mannervik B Ketterer 《The Biochemical journal》1989,260(3):785-788
GSSG selectively elutes two GSH transferases from a mixture of rat GSH transferases bound to a GSH-agarose affinity matrix. One is a form of GSH transferase 1-1 and the other is shown to be GSH transferase 8-8. By using tissues that lack this form of GSH transferase 1-1 (e.g. lung), GSH transferase 8-8 may thus be purified from cytosol in a single step. Quantitative analysis of the tissue distribution of GSH transferase 8-8 was obtained by h.p.l.c. 相似文献
46.
Zaida Herrador Mar Siles-Lucas Pilar Aparicio Rogelio Lopez-Velez Alin Gherasim Teresa Garate Agustín Benito 《PLoS neglected tropical diseases》2016,10(8)
BackgroundCystic echinococcosis (CE) is a parasitic disease caused by the tapeworm Echinococcus granulosus. Although present throughout Europe, deficiencies in the official reporting of CE result in under-reporting and misreporting of this disease, which in turn is reflected in the wrong opinion that CE is not an important health problem. By using an alternative data source, this study aimed at describing the clinical and temporal-spatial characteristics of CE hospitalizations in Spain between 1997 and 2012.ConclusionsHospitalizations distribution was uneven by year and autonomous region. Although CE hospitalization rates have decreased considerably due to the success of control programs, it remains a public health problem due to its severity and economic impact. Therefore, it would be desirable to improve its oversight and surveillance, since officially reported data are underestimating the real burden of CE in Spain. 相似文献
47.
Work in Xenopus laevis produced the first molecular explanation for neural specification, the default model, where inactivation of the BMP pathway in ectodermal cells changes fates from epidermal to neural. This review covers the present status of our understanding of neural specification, with emphasis on Xenopus, but including relevant facts in other model systems. While recent experiments have increased the complexity of the molecular picture, they have also provided additional support for the default model and the central position of the BMP pathway. We conclude that synergy between accumulated knowledge and technical progress will maintain Xenopus at the forefront of research in neural development. 相似文献
48.
Virtualization technology promises to provide better isolation and consolidation in traditional servers. However, with VMM (virtual machine monitor) layer getting involved, virtualization system changes the architecture of traditional software stack, bringing about limitations in resource allocating. The non-uniform VCPU (virtual CPU)-PCPU (physical CPU) mapping, deriving from both the configuration or the deployment of virtual machines and the dynamic runtime feature of applications, causes the different percentage of processor allocation in the same physical machine,and the VCPUs mapped these PCPUs will gain asymmetric performance. The guest OS, however, is agnostic to the non-uniformity. With assumption that all VCPUs have the same performance, it can carry out sub-optimal policies when allocating virtual resource for applications. Likewise, application runtime system can also make the same mistakes. Our focus in this paper is to understand the performance implications of the non-uniform VCPU-PCPU mapping in a virtualization system. Based on real measurements of a virtualization system with state of art multi-core processors running different commercial and emerging applications, we demonstrate that the presence of the non-uniform mapping has negative impacts on application’s performance predictability. This study aims to provide timely and practical insights on the problem of non-uniform VCPU mapping, when virtual machines being deployed and configured, in emerging cloud. 相似文献
49.
H Gao G Chakraborty AP Lee-Lim Q Mo M Decker A Vonica R Shen E Brogi AH Brivanlou FG Giancotti 《Cell》2012,150(4):764-779
The mechanistic underpinnings of metastatic dormancy and reactivation are poorly understood. A gain-of-function cDNA screen reveals that Coco, a secreted antagonist of TGF-β ligands, induces dormant breast cancer cells to undergo reactivation in the lung. Mechanistic studies indicate that Coco exerts this effect by blocking lung-derived BMP ligands. Whereas Coco enhances the manifestation of traits associated with cancer stem cells, BMP signaling suppresses it. Coco induces a discrete gene expression signature, which is strongly associated with metastatic relapse to the lung, but not to the bone or brain in patients. Experiments in mouse models suggest that these latter organs contain niches devoid of bioactive BMP. These findings reveal that metastasis-initiating cells need to overcome organ-specific antimetastatic signals in order to undergo reactivation. 相似文献
50.
Male Wistar rats were subjected to right-unilateral 6-hydroxydopamine (6-OHDA) (2 μg/μl) lesions of the ventral tegmental area (VTA) or the substantia nigra (SN), or were sham-operated, and their ability to acquire
the operant task was studied by means of Y-maze and shuttle-box tasks. Lesions of both the VTA and the SN resulted in an impairment
of conditioned avoidance response and increase of crossing latency tested by means of shuttle-box task, suggesting significant
effects of long-term memory. 6-OHDA significantly decreased spontaneous alternation in Y-maze task, suggesting effects on
spatial memory, especially on short-term memory. In addition, 6-OHDA lesions of the VTA and the SN induced reductions in superoxide
dismutase (SOD), glutathione peroxidase (GPX) activities and malondialdehyde (MDA) levels in the temporal lobe rather than
in the frontal lobe homogenates. Our results provide further support for the toxic effects of 6-OHDA-induced memory impairment
and oxidative stress with relevance for Parkinson’s disease. 相似文献