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Summary Horse urinary kallikrein was shown to hydrolyze histones from calf thymus and chicken nuclei erythrocytes. The hydrolysis is inhibited by benzamidine and hyposulfite but not by soy-bean trypsin inhibitor; horse plasma kallikrein also produces this hydrolysis.Work supported by grants from Projeto BIOQ/FAPESP (São Paulo), FINEP (Rio) and CNPq (Rio).Fellow from CNPq, from Instituto Biológico (São Paulo).  相似文献   
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This paper is drawn from PhD research funded by the Saudi government on the policy and governance of Saudi schools (Algraini 2017. A critical systemic approach to human development in education: a case study of the Ministry of Education in Saudi Arabia). The aim of this article is to address human development challenges using the Critical Systems Heuristics approach. The results show that the central policy framework limits the opportunity for teachers and learners to contribute to shaping the curriculum and the process for human development. The Saudi Ministry of Education needs to: a) develop policy that takes into account the structure and the processes that shape education outcomes and b) to represent the voices of service users and service providers who have different and overlapping views.  相似文献   
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6-烷氧基-2-烷硫基嘌呤是一类潜在的具有生理功能和药理活性的化合物。本文以2-氨基-6-氯嘌呤(1)为原料,与烯丙基溴反应得9-烯丙基-2-氨基-6-氯嘌呤(2);随后和醇钠反应,合成相应的6-位芳香亲核取代产物(3);再进一步与亚硝酸异戊酯和二甲二硫醚发生重氮-烷硫化反应,生成9-烯丙基-6-烷氧基-2-甲硫基嘌呤(4);最后经硼氢化-氧化反应可得9-(3-和2-羟基丙基)-6-烷氧基-2-甲硫基嘌呤化合物(5和6)。经过4步反应,共合成了13种新化合物,其结构经1H-NMR、13C-NMR和HRMS等表征确证。  相似文献   
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There are many handbooks on research and evaluation that are useful to read but difficult to implement in complex networked situations. This paper describes the ArtsSmarts Inquiry Model (AIM), which is founded on action research principles, and allows for networks of partners to conduct program evaluations. The AIM emerged from a special research project funded by the Canadian Council on Learning as a method of increasing research capacity within ArtsSmarts, a non-profit organization that facilitates relationships between artists and teachers in the classroom. Because ArtsSmarts is based on partnerships with distributed capacity, the research framework had to be flexible, while providing a structure with a universal core to facilitate the sharing of stories. This paper outlines the development process, the design of the framework, and some of the reflections from participating partners.  相似文献   
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Summary In spinal unanesthetized cats, pyridoxine pretreatment significantly enhanced the diazepam-induced increase in dorsal root potentials and dorsal root reflexes.Acknowledgments. This work was supported by a grant from the Lebanese National Research Council. The authors wish to thank Mr M. Shakarji for technical assistance in this investigation.  相似文献   
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A preliminary list of Diptera (Insecta) in Garf Raydah Nature Reserve (GRNR), Kingdom of Saudi Arabia (KSA) with remarks on their zoogeographic affinities is presented. This is the first in a series of planned faunal studies on different insect orders as an output of a project proposed to study the entire entomofauna of GRNR. A total number of 177 Diptera species belonging to 130 genera, representing 38 families has been listed. Some species have been identified only to genus and listed herein as genera that were not previously recorded from KSA or of a taxonomic or faunal importance. The list records five families, 11 genera and 31 species for the first time in KSA, namely: the families Acroceridae, Asteiidae, Chamaemyiidae, Heleomyzidae and Pipunculidae; the genera Acrocera (Acroceridae), Eremisca (Asilidae), Asteia (Asteiidae), Chamaemyia sp. (Chamaemyiidae), Ochthera (Ephydridae), Physoconops (Conopidae), Pseudoleria (Heleo-myzidae), Salentia (Therevidae), Sapromyza (Lauxaniidae), Sternobrithes (Stratiomyidae), Tomosvaryella (Pipunculidae); and the species Apoclea algira (Linnaeus), Apoclea femoralis (Wiedemann), Promachus rectangularis Loew, Eremisca sp. and Oligopogon nitidus Efflatoun [Asilidae]; Phycus sp., Salentia sp. and Thereva nobilitata (Fabricius) [Therevidae]; Drapetis flavipes Macquartand Platypalpus flavicornis (Meigen) [Hybotidae]; Acrocera sp.1 and Acrocera sp.2 [Acroceridae]; Aspida-cantha atra Kertesz and Sternobrithes sp. [Stratiomyidae]; Tomos-varyella sp.1 and Tomosvaryella sp.2 [Pipunculidae]; Eristalinus taeniops (Wiedemann) and Eumerus amoenus Loew [Syrphidae]; Asteia sp. [Asteiidae]; Chamaemyia sp. [Chamaemyiidae]; Physoconops sp., and Thecophora fulvipes Rubineau-Desvoidy [Conopidae]; Ochthera sp. [Ephydridae]; Pseudoleria pectinata (Loew) [Heleomyzidae]; Cestrotus megacephalus Loew and Sapromyza sp. [Lauxaniidae]; Campylocera oculata Hendel [Pyrgotidae]; Australosepsis niveipennis (Becker) [Sepsidae]; Metasphenisca transilis Munro [Tephritidae]; Anthomyia xanthopus (Hennig) [Anthomyiidae]; and Sarcophaga inaequalis Austen [Sarcophagidae]. More than 50% of the recorded fly species are of an Afrotropical affinity, whereas the Palaearctic elements did not exceed 20%. Only 7% of the species were of both Afrotropical and Palaearctic affinities, and Oriental elements were close to nil. This emphasizes the fact that the southwestern part of KSA, including the study area, belonging to Asir Province, ought to be part of the Afrotropical Region rather than the the Palaearctic Region.  相似文献   
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研究了有限生成线性群的极大抛物子群和Borel子群的正则结构.通过上述子群来计算一般有限线性群GL(n,q)的诱导特征标;并用计算机编程系统GAP来检验和推广我们的结果.  相似文献   
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