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221.
Adamson Lauren B.; Bakeman Roger; Smith Connie B.; Walters Anne S. 《Canadian Metallurgical Quarterly》1987,23(3):383
Adults are often viewed as skilled interpreters who understand infants' acts even when they are unconventional and diffuse. The first step in interpretation—the selection of acts from the stream of behavior—is examined here. One hundred forty adults (mothers and fathers and other men and women) viewed videotapes of 9-, 15-, and 21-month-old infants. One half of the subjects were asked to note times when they thought the baby performed a meaningful act; the other half of the subjects were asked to note an intentionally communicative act. Times were recorded by a microcomputer. Parents selected more meaningful acts than nonparents and agreed more about selection of all acts. All subjects agreed more about intentionally communicative than about meaningful acts, at least for older infants. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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F Cima MG Marin V Matozzo L Da Ros L Ballarin 《Canadian Metallurgical Quarterly》1998,37(14-15):3035-3045
One of the most harmful groups of coastal pollutants is the organotin compounds (OTCs) which have severe effects on both aquatic organisms and mammals including humans. The immunotoxic effects of OTCs were studied in the cultivated clam Tapes philippinarum by determining the immunosuppressant role on in vitro yeast phagocytosis at low doses (0.01, 0.05, 0.1 microM). The phagocytic index was significantly reduced in an irreversible non-lethal manner depending on concentration and lipophilic affinity. The order of inhibition was TBT > or = DBT > MBT for butyltins and TPTC > TPTA > or = TPTH for triphenyltins. 相似文献
224.
BM Fraga P González R Guillermo MG Hernández 《Canadian Metallurgical Quarterly》1998,61(10):1237-1241
Biotransformations of jhanol (18-hydroxymanoyl oxide) (2), jhanidiol (1beta,18-dihydroxymanoyl oxide) (3), and 1-oxo-jhanol (1-oxo-18-hydroxymanoyl oxide) (4) by the fungus Mucor plumbeus have been studied. In the incubation of 2 there exists a preference for hydroxylation at C-2(alpha) (8) and C-6(beta) (9-11) and, to a lesser degree, at C-1(alpha) (7), C-11(alpha) (6), and C-11(beta) (5 and 10). In the second substrate (3), the presence of a 1beta-hydroxyl group inhibits 6beta- or 11-hydroxylation. Epoxidation of the vinyl group constitutes the main reaction, with the positions 2alpha (14) and 3beta (15) being hydroxylated. In the incubation of 4, there was a preference for 6beta-hydroxylation (21) or epoxidation of the vinyl group (22). Other hydroxylations observed were at the 2alpha (19), 2beta (20), 3alpha (23), 3beta (24), and 11beta (18) positions. 相似文献
225.
MG Tvorogova VP Lupanov EIu Nuraliev TM Za?tseva VV Kukharchuk VN Titov 《Canadian Metallurgical Quarterly》1998,70(8):17-21
AIM: Evaluation of effectiveness of hypolipidemic action of probucol in doses 500 and 1000 mg/day and comparison of probucol blood concentrations on the treatment month 3 and 6. MATERIALS AND METHODS: Probucol (Akrikhin, Russia) was given to 41 patients with primary hypercholesterolemia in a dose 500 mg/day. 3 months later the patients were divided into two groups. Group 1 patients exhibited a > 10% decrease in cholesterol levels and continued to take probucol in the dose 500 mg/day. Group 2 patients were crossed over to higher cholesterol dose--up to 1000 mg/day. Lipids levels were measured by enzyme tests, apoproteins--by immunoturbidimetry and immunodiffusion, probucol concentrations--by high-performance liquid chromatography. RESULTS: After 3 months of treatment, cholesterol lowered by 14.3 and 9.2% in groups 1 and 2, respectively. After 6 months, by 19.7 and 12.9%, respectively. Probucol concentrations in blood were higher after 6 months of treatment than after 3 months in both groups. No significant differences existed between the groups by probucol concentrations in 3 and 6 months. CONCLUSION: Hypolipidemic effect of probucol depended on the individual features of lipoproteins metabolic disorders rather than the drug blood concentration. Larger probucol doses fail to reduce cholesterol further. 相似文献
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JH Son JH Chung SO Huh DH Park C Peng MG Rosenblum YI Chung TH Joh 《Canadian Metallurgical Quarterly》1996,37(1-2):32-40
Tryptophan hydroxylase (TPH) is the first enzyme in both serotonin and melatonin biosynthesis in neuroendocrine cells of the pineal gland. The lack of immortalized neuroendocrine pineal cell lines has been a major obstacle to the study of the tissue-specific and circadian regulation of TPH gene expression in the pineal gland. Previously, we demonstrated that a 6.1 kb 5' upstream region of the mouse TPH gene directs the restricted expression of a lacZ reporter gene to the pineal gland and the raphe nuclei of transgenic mice. Therefore, to develop TPH-expressing pineal cell lines we first established transgenic mice carrying a construct consisting of 6.1 kb of 5' flanking region fused to the SV40 T-antigen. These animals developed highly invasive pineal tumors and died at 12-15 weeks of age. The pineal tumors obtained from the transgenic mice were utilized to establish the immortalized pinealocyte-derived cell lines. These cells express two marker enzymes, TPH and serotonin N-acetyltransferase (NAT). In pineal gland TPH and NAT expressions have been known to be regulated during circadian cycle. The two established cell lines therefore promise to be a valuable in vitro model system for the study of the rhythmic nature of the pineal function at molecular level in mammal. 相似文献
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229.
For about a quarter of a century, concerns have been expressed about published biomedical research. It became more acute after some published research and broad dissemination was found fraudulent. With the emphasis now being placed on scientifically validated or evidence-based practice, it has become more imperative that clinical guidelines be based on credible information in our textbooks and research literature. Since the early 1990s, it has been found that much of the research in our electronic databases does not meet quality standards and often is irrelevant, calling into questions problems with peer review, including the selection and publication process of our journals. This column is devoted to calling attention to these problems not only to CRNAs and other researchers, but also to the consumers of research who often use it to make changes in their practice. It also calls attention to the CRNA community about the movement toward calls for greater accountability in practice, both as to quality and cost, from which the movement toward evidence-based practice, the identification and benchmarking of best practices, and the development and implementation of clinical practice guideline has evolved. To feel ownership in anesthesia-related clinical practice guidelines, CRNAs must become involved in their development and implementation. 相似文献
230.
L Ridder F Briganti MG Boersma S Boeren EH Vis A Scozzafava C Veeger IM Rietjens 《Canadian Metallurgical Quarterly》1998,257(1):92-100
Dot-immunoblotting assay (DIA) using five monoclonal antibodies (MAbs) to infectious bronchitis virus (IBV) was used to detect and classify the viruses propagated in embryonated chicken eggs. Using a group-specific MAb 3F5, 10 reference strains and 12 Korean isolates of IBV were successfully detected by DIA, and the lowest virus titer of IBV detected by DIA was approximately less than 10(3.8) mean embryo infective dose/ml. For evaluating the diagnostic efficiency, DIA was compared with the conventional infectious bronchitis (IB) diagnostic method. IBV antigens in allantoic fluid from embryonated eggs inoculated with IB-suspected field samples were specifically detected by DIA within only one or two egg passages, whereas the conventional embryonated egg inoculation method required four to seven egg passages for confirming IBV infection. These results indicated that DIA could significantly reduce time and cost for IB diagnosis. For examining the possibility of classifying IBV by DIA, four strain-specific MAbs, 3A4, 2A3, 6F7, and 2C6, were used. According to the MAb reacting patterns to the IBV antigens, the 10 IBV reference strains were classified into six groups; seven strains belonged to three different groups, and the other three strains each belonged to an individual group. In the case of 12 Korean isolates of IBV, they were classified in six groups. Among the six groups, the MAb reacting patterns of three groups matched those of the IBV reference strains, but the others did not. These data suggest that at least three variant serotypes of IBV exist in Korea. 相似文献