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排序方式: 共有76条查询结果,搜索用时 62 毫秒
1.
Benson Janette B.; Cherny S. S.; Haith Marshall M.; Fulker David W. 《Canadian Metallurgical Quarterly》1993,29(3):434
Assessed infant predictors of adult IQ with same-sex infant twins (114 pairs) and their parents. The midtwin–midparent design permits the rapid assessment of infant measures to predict later behavior, because the midparent score serves as a proxy for the infant's potential score at maturity. At 5, 7, and 9 mo, Ss were observed on the Fagan Test of Infant Intelligence, hand preference, vocalizations, selected Bayley Scales of Infant Development items, and a modified Bayley Infant Behavior Record. At 8 mo, Ss received the Visual Expectation Paradigm and an auditory discrimination task. Their parents received the Wechsler Adult Intelligence Scale—Revised (WAIS—R). Some infant measures, indicative of information processing, language ability, and temperament, predicted midparent IQ. This study extended and partially replicated findings from a previous midtwin–midparent cohort (L. F. DiLalla et al; see record 1991-04066-001). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
Thomas Janette A.; Arnold John R.P.; Basran Jaswir; Andrews Julie; Roberts Gordon C.K.; Birdsall Berry; Feeney James 《Protein engineering, design & selection : PEDS》1994,7(6):783-792
A mutant of Lactobacillus casei dihydrofolate reductase hasbeen constructed in which Thr63, a residue which interacts withthe 2'-phosphate group of the bound coenzyme, is replaced byalanine. This substitution does not affect kcat, but producesan 800-fold increase in the Km for NADPH, which reflects dissociationof NADPH from the enzyme-NADPH-tetrahydrofolate complex, anda 625-fold increase (corresponding to 3.8 kcal/mol) in the dissociationconstant for the enzyme-NADPH complex. The difference in magnitudeof these effects indicates a small effect of the substitutionon the negative cooperativity between NADPH and tetrahydrofolate.Stopped-flow studies of the kinetics of NADPH binding show thatthe weaker binding arises predominantly from a decrease in theassociation rate constant. NMR spectroscopy was used to comparethe structures of the mutant and wild-type enzymes in solution,in their complexes with methotrexate and with methotrexate andNADPH. This showed that only minimal structural changes resultfrom the mutation; a total of 47 residues were monitored fromtheir resolved 1H resonances, and of these nine in the binarycomplex and six in the ternary differed in chemical shift betweenmutant and wild-type enzyme. These affected residues are confinedto the immediate vicinity of residue 63. There is a substantialdifference in the 31P chemical shift of the 2'-phosphate ofthe bound coenzyme, reflecting the loss of the interaction withthe side chain of Thr63. The only changes in nuclear Overhausereffects (NOEs) observed were decreases in the intensity of NOEsbetween protons of the adenine ring of the bound coenzyme andthe nearby residues Leu62 and Ile102, showing that the substitutionof Thr63 does cause a change in the position or orientationof the adenine ring in its binding site. 相似文献
3.
In collaboration with the Armed Forces Institute of Pathology's Department of Defense DNA Registry, the National Institute of Standards and Technology recently evaluated the performance of a short tandem repeat multiplex with dried whole blood stains on four different commercially available identification card matrixes. DNA from 70 stains that had been stored for 19 months at ambient temperature was extracted or directly amplified and then processed using routine methods. All four storage media provided fully typeable (qualitatively identical) samples. After standardization, the average among-locus fluorescence intensity (electropherographic peak height or area) provided a suitable metric for quantitative analysis of the relative amounts of amplifiable DNA in an archived sample. The amounts of DNA in Chelex extracts from stains on two untreated high-purity cotton linter pulp papers and a paper treated with a DNA-binding coating were essentially identical. Average intensities for the aqueous extracts from a paper treated with a DNA-releasing coating were somewhat lower but also somewhat less variable than for the Chelex extracts. Average intensities of directly amplified punches of the DNA-binding paper were much larger but somewhat more variable than the Chelex extracts. Approximately 25% of the observed variation among the intensity measurements is shared among the four media and thus can be attributed to intrinsic variation in white blood count among the donors. All of the evaluated media adequately "bank" forensically useful DNA in well-dried whole blood stains for at least 19 months at ambient temperature. 相似文献
4.
Rholes William S.; Blackwell Janette; Jordan Carol; Walters Connie 《Canadian Metallurgical Quarterly》1980,16(6):616
Examined susceptibility to learned helplessness among 20 children from each of kindergarten, Grade 1, Grade 3, and Grade 5 classes by exposing groups of Ss to either repeated failure or repeated success on hidden figures problems. Helplessness was measured by Ss' persistence in looking for hidden figures and their capacity to find them following repeated success or failure. It was hypothesized that younger Ss would be less susceptible to helplessness than older ones, due to age-related differences in causal attributions for success and failure. Results confirm the hypothesis in that failure, relative to success, had significantly less influence on the level of helplessness in younger Ss' behavior. It is suggested that the development of attributional capabilities during the preschool and early elementary school years has important ramifications for cognitive theories of motivation. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
Megan L. Ranney Michael J. Mello Janette B. Baird Peter R. Chai Melissa A. Clark 《Accident; analysis and prevention》2010,42(6):2057-2062
Helmets significantly decrease morbidity and mortality from motorcycle crashes, but many areas of the world lack universal helmet laws. To educate motorcyclists in areas without helmet laws, more knowledge of motorcyclists’ helmet beliefs is needed.A web-based survey was therefore designed to assess motorcyclists’ attitudes, norms and behaviors towards helmets in a U.S. state with a limited helmet law. Of 445 survey respondents, 68.4% of respondents reported always wearing a helmet. The not-always-helmeted riders were more likely than the always-helmeted to be male; to bave less education; and to have a history of previous motorcycle crashes and injuries. Although both groups had taken rider training classes, fewer of the not-always-helmeted had learned how to ride in a class. The strongest correlates of being not-always-helmeted (vs. always-helmeted) were attitudes that helmets were not protective and impaired sight/hearing; and the normative belief that they would only wear helmets if forced by law. Because attitudes are often more easily changed than normative beliefs, education may increase helmet use. However, less than half of riders in this state with a mandatory education program learned how to ride from a rider education course, and 44% of non-helmeted said they would only wear a helmet if forced by law. Legislation may therefore be a more efficient and effective strategy than education to increase helmet use. 相似文献
6.
Tara Matthews Janette Fong F. Wai-Ling Ho-Ching Jennifer Mankoff 《Behaviour & Information Technology》2006,25(4):333-351
Sounds such as co-workers chatting nearby or a dripping faucet help us maintain awareness of and respond to our surroundings. Without a tool that communicates ambient sounds in a non-auditory manner, maintaining this awareness is difficult for people who are deaf. We present an iterative investigation of peripheral, visual displays of ambient sounds. Our major contributions are: (1) a rich understanding of what ambient sounds are useful to people who are deaf, (2) a set of visual and functional requirements for a peripheral sound display, based on feedback from people who are deaf, (3) lab-based evaluations investigating the characteristics of four prototypes, and (4) a set of design guidelines for successful ambient audio displays, based on a comparison of four implemented prototypes and user feedback. Our work provides valuable information about the sound awareness needs of the deaf and can help to inform further design of such applications. 相似文献
7.
F Poulat F Girard MP Chevron C Gozé X Rebillard B Calas N Lamb P Berta 《Canadian Metallurgical Quarterly》1995,128(5):737-748
We have studied the expression of the human SRY protein (termed p27SRY) in two different cell lines by using specific antibodies. Confocal microscopy enabled us to localize p27SRY precisely in the nucleus in a discrete punctuate pattern. Furthermore, through microinjection experiments, we have demonstrated that the localization of the p27SRY protein into the nucleus was an event involving the NH2-terminal part of the high mobility group (HMG) domain. With the help of several synthetic peptides and various p27SRY mutants, we have characterized a bipartite basic motif in this part of the protein corresponding to a nuclear localization signal. This nuclear localization signal appears to be highly conserved in SRY box- and HMB box-containing proteins, suggesting common properties of nuclear targeting within the HMG box protein family. 相似文献
8.
9.
Gymnodinoid dinoflagellate symbionts, commonly referred to as zooxanthellae, are widely distributed among marine invertebrates.
It has been assumed that they represent only one species,Gymnodinium microadriaticum. The fatty acid composition of total lipids and galactolipids of zooxanthellae isolated from 8 species of corals, 3 species
of clams and a foraminiferan have been analyzed and found to vary according to the host. For example, the content of eicosapentaenoic
acid in clam zooxanthellae monogalactosyldiacylglycerol was less than 2%, whereas in the same lipid from coral zooxanthellae,
the content ranged from 9 to 22%. Corresponding values for the acid in digalactosyl-diacylglycerol were 1–8% from clam zooxanthellae
and 23–40% from coral zooxanthellae. Coral zooxanthellae monogalactosyldiacylglycerol contain higher levels of octadecatetraenoic
acid than are found in digalactosyldiacylglycerol, whereas the reverse is true in clam zooxanthellae. The fatty acid composition
of the lipids of an axenic culture of zooxanthellae isolated from the clamTridacna maxima are similar to those of cells freshly isolated from the host. The results suggest either that the host is capable of affecting
the fatty acid metabolism of the symbiont or that different strains of zooxanthellae occur in corals and clams. 相似文献
10.
Godding Phillip R.; Fitterling James M.; Schmitz Joy M.; Seville Janette L.; Parisi Sharon A. 《Canadian Metallurgical Quarterly》1992,6(1):34
Assessed the discriminative utility of a brief assessment procedure for quantifying cognitive status in alcoholics and the impact of existing cognitive status on acquisition of information presented during treatment. 112 male patients (aged 20–77 yrs), consecutively admitted to an inpatient alcohol treatment program, were assessed at admission and discharge. The 30-min assessment protocol included the Rey Auditory Verbal Learning Task (M. D. Lezak, 1983), portions of the Wechsler Memory Scale, and a brief structured interview that assessed treatment-relevant knowledge. These measures were able to differentiate performance levels related to age and drinking history. Recent drinking behavior and cognitive function may only moderately influence acquisition of treatment program content. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献