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Tseng SC Arcand JL Brugger JM Finn M Olson AJ Somers S 《Library resources & technical services》1990,34(2):139-157
Serials, one of the more complicated areas of library technical endeavors, has lacked the benefit of standards for a long time. Even now, with standards beginning to be available, the majority of institutions are not working within standard serials formats. A survey to determine the use of serials standards in libraries was conducted in 1988 by the American Library Association, Resources and Technical Services Division, Serials Section, Committee to Study Serials Standards. In the spring of 1988 a survey was sent to a group encompassing the Association of Research Libraries members, CONSER participants, United States Newspaper Program participants, Microform Project libraries, and some vendors and librarians who attended the Committee meetings on a regular basis. The survey questionnaire assessed the current level of serials standards awareness of librarians and vendors. Topics included the type of serials systems used, standards relevant to serials control and union listing and whether or not they are implemented, types and levels of training staff received in the application of standards, benefits of the standards, and areas where standards are most needed. 相似文献
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在发明激光几年之后,激光曾被描述为“正在寻找的一个问题的解”。如今,它则被认为是一种能够进行切割,治疗和通讯的光。激光正日益广泛地应用于通讯、工程学的几乎全部分支,以及医药和外科手术,当然还有国防。对那些不断寻求更高精度的科学家来说,激光是极其有用的。 相似文献
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Not all young children benefit from book exposure in preschool age. It is claimed that the ability to hold information in
mind (short-term memory), to ignore distraction (inhibition), and to focus attention and stay focused (sustained attention) may have a moderating effect on children’s reactions to the home literacy environment. In a group of 228 junior kindergarten
children with a native Dutch background, with a mean age of 54.29 months (SD = 2.12 months), we explored therefore the relationship
between book exposure, cognitive control and early literacy skills. Parents filled in a HLE questionnaire (book sharing frequency
and an author recognition checklist as indicator of parental leisure reading habits), and children completed several tests
in individual sessions with the researcher (a book-cover recognition test, PPVT, letter knowledge test, the subtests categories
and patterns of the SON, and cognitive control measures namely digit span of the KABC, a peg tapping task and sustained attention
of the ANT). Main findings were: (1) Children’s storybook knowledge mediated the relationship between home literacy environment
and literacy skills. (2) Both vocabulary and letter knowledge were predicted by book exposure. (3) Short-term memory predicted
vocabulary over and above book exposure. (4) None of the cognitive control mechanisms moderated the beneficial effects of
book exposure. 相似文献
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Machado M Willardson JM Silva DR Frigulha IC Koch AJ Souza SC 《Research quarterly for exercise and sport》2012,83(2):276-281
In the current study, we examined the relationship between serum creatine kinase (CK) activity following upper body resistance exercise with a 1- or 3-min rest between sets. Twenty men performed two sessions, each consisting of four sets with a 10-repetition maximum load. The results demonstrated significantly greater volume for the 3-min condition (M = 4156 kg, SD = 867, for 3 min; vs. M = 3503 kg SD = 759, for 1 min; p < .001), with no significant differences in delta CK activity between conditions (p = .574). Nevertheless, there was a weak correlation between the delta CK activity and total volume of exercise completed (r = .55 with a 1-min rest, and r = .45 with a 3-min rest). Therefore, the volume following upper body resistance exercise correlates weakly with serum CK levels, irrespective of rest interval length between sets. 相似文献
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Dang SC Jiang DL Chen M Li D Zhang JX 《Journal of Zhejiang University. Science. B》2010,11(11):828-835
Objectives:Severe acute pancreatitis(SAP) can lead to acute lung injury(ALI) .The purpose of this paper is to investigate the protective effect of clodronate-containing liposomes on ALI in rats with SAP.Methods:The thin film method was used to prepare liposomes.Sprague-Dawley rats were randomly divided into three groups.After the SAP model was established by injecting 5%(w/v) sodium taurocholate(2 ml/kg body weight) into the subcapsular space of the pancreata,normal saline was administered to the control(C) group,phosphate buffer solution(PBS) -containing liposome to the Pgroup,and clodronate-containing liposome to the Tgroup through tail veins.Blood samples were obtained from the superior mesenteric vein at 2 and 6 h to measure the levels of amylase,interleukin-6(IL-6) ,and tumor necrosis factor-α(TNF-α) .Morphological changes in the pancreata and lung were observed using hematoxylin and eosin(HE) staining,while cell apoptosis was detected using terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling(TUNEL) .In addition,the macrophage marker cluster of differentiation 68(CD68) in lung tissue was detected with immunohistochemistry.Results:Blood levels of amylase,IL-6,and TNF-αwere significantly increased in the Pgroup compared to those in the Tgroup(P0.05) .In the Tgroup,large numbers of TUNEL-positive cells were observed,but no or few in the C and Pgroups.Gross inspection and HE staining of pancreata and lung showed dramatic tissue damage,including inflammation and necrosis in the Pgroup.Less remarkable changes were noted in the Tgroup,and the C group exhibited normal histology.The histological scores according to Kaiser's criteria were consistent with HE findings.The number of CD68-positive macrophages decreased in the Tgroup.Conclusions:Clodronate-containing liposomes have a protective effect against ALI in rats with SAP.Blockade of macrophages may represent a novel therapeutic strategy in SAP. 相似文献
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