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71.
随着家电行业国际化竞争的加剧,家电企业纷纷将注意力转向"创新"这个时下热门的词汇以期在竞争中能够取得领先。 相似文献
72.
Brook trout (Salvelinus fontinalis) are found throughout Lake Superior, Lake Nipigon, and their tributaries. Lacustrine and adfluvial life history variants were historically popular with anglers and were called coasters; coaster brook trout populations are now severely reduced and are of conservation concern. Coasters were known to grow larger and mature later than their stream resident counterparts. This study compared movement patterns, age, size, condition, and relative weight of wild coaster and resident brook trout from the Hurricane River, Pictured Rocks National Lakeshore, Michigan. Wild brook trout ≥ 100 mm from the Hurricane River downstream from Hurricane Falls were tagged with passive integrated transponder tags and monitored for stream-lake movement behavior from May 2003 to November 2007. During 2006 and 2007, brook trout were scale sampled and aged to construct a regression that was then used to calculate the age of all brook trout tagged from 2003 to 2007. Most brook trout movement took place in the fall with October the peak month of emigration with a secondary peak in late spring/early summer and some activity nearly year round. There were no differences found in age structure, size or condition between coasters and residents while in the stream. Our data suggest that a priori growth differences are not determining the expression of coaster outmigration and that stream-lake movements made by coasters, likely driven by habitat requirements, may be highly flexible and facultative. 相似文献
73.
As our elderly population increases in proportion with respect to the rest of society, age-related driving impairments are increasing in importance as a public health concern. In this context, health professionals play an important role in identifying impaired drivers. This situation is complicated for two reasons: discussion of driving cessation is a sensitive topic for both health professionals and the elderly, and physicians have limited familiarity with the current American Medical Association (AMA) screening guidelines or mandated reporting laws. 相似文献
74.
Fetal alcohol syndrome (FAS) is the leading birth defect in the United States, yet few treatment options exist for children afflicted with this disorder. Although play therapy has demonstrated its efficacy with numerous special populations, as of today, no research has been conducted on its use with FAS. This article presents an overview of current data on FAS, an argument for the use of child-centered play therapy for children diagnosed FAS, and suggests areas of research needs. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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77.
Lower task persistence in smokers with schizophrenia as compared to non-psychiatric control smokers.
Steinberg Marc L.; Williams Jill M.; Gandhi Kunal K.; Foulds Jonathan; Brandon Thomas H. 《Canadian Metallurgical Quarterly》2010,24(4):724
One contributing factor to difficulty in quitting smoking may be task persistence, which can be viewed as a behavioral manifestation of distress tolerance, and describes the act of persisting in a difficult or effortful task. Task persistence was assessed in smokers with schizophrenia and schizoaffective disorder (SZ/SA; N = 71) and non-psychiatric controls (N = 78) before a quit attempt. These data support the hypothesis that smokers with SZ/SA display less task persistence than do non-psychiatric controls when persistence is measured via mirror tracing and a 2-item persistence measure. Lower persistence may partially explain the reduced smoking cessation successes of smokers with SZ/SA as compared to the general population. These data also replicate findings regarding relationships between histories of ability to quit smoking and task persistence and expand them to a new population of smokers. The absence of a diagnostic status by length of previous abstinence interaction suggests that the contribution of task persistence to smoking cessation is similar for smokers with and without schizophrenia. Future studies should evaluate the ability of task persistence to predict abstinence from cigarettes prospectively among smokers with schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
Short communication: relationship between body growth and mammary development in dairy heifers 总被引:1,自引:0,他引:1
Silva LF VandeHaar MJ Whitlock BK Radcliff RP Tucker HA 《Journal of dairy science》2002,85(10):2600-2602
Our objective was to determine if prepubertal rate of body weight (BW) gain, independent of diet, was related to mammary development of dairy heifers. Data from two studies recently conducted at Michigan State University were used to identify factors, within a dietary treatment group, that would account for variation in first lactation milk production or amount of mammary parenchymal DNA at the time of puberty. Factors analyzed for variation in milk production during first lactation were: postpartum BW, prepubertal BW gain, gestational BW gain, postpartum BW gain, body condition score (BCS) at breeding, and BCS at calving. Factors analyzed for variation in mammary parenchymal DNA at puberty were: BW at slaughter, age at puberty, prepubertal BW gain and body protein and body fat content at slaughter. For both analyses, prepubertal BW gain did not account for any of the variation in mammary development. The only significant covariate for the milk production model (r2 = 0.44) was BCS at breeding. Similarly, the only significant covariate in the parenchymal DNA model (r2 = 0.22) was body fat content at slaughter. These results suggest that, within a dietary treatment, heifers that grow faster do not have impaired mammary development, and increased body fatness may be a better predictor of impaired mammary development than BW gain. 相似文献
79.
The electrode response time and the measured concentrations during dynamic catecholamine changes were compared using constant potential amperometry and fast-scan cyclic voltammetry. The amperometric response to a rectangular pulse of catecholamine is more rectangular than the cyclic voltammetric response; however, the response times are very similar when, during cyclic voltammetry, the temporal lag due to adsorption and desorption of catecholamine to the electrode is removed by deconvolution. Deconvolution of cyclic voltammetry data was applied to stimulated dopamine release in vivo, allowing for modeling of release and uptake kinetics and to measure catecholamine release from single cells, resulting in better resolution of peaks from single vesicles. In vitro postcalibrations were performed to calculate concentrations of catecholamine measured with cyclic voltammetry and amperometry. The addition of 600 microM ascorbic acid to the postcalibration buffer, allowing a catalytic reaction to regenerate dopamine, resulted in similar calculated concentrations for stimulated release of dopamine using amperometry and cyclic voltammetry. Using deconvoluted cyclic voltammetry to remove the response time lag and adding ascorbic acid to the calibration buffer, the shape and concentration of dynamic catecholamine changes are very similar when measured with constant potential amperometry and cyclic voltammetry. 相似文献
80.
Grimes Jill M.; Ricci Lesley A.; Melloni Richard H. Jr. 《Canadian Metallurgical Quarterly》2006,120(1):115
In hamsters, adolescent anabolic-androgenic steroid (AAS) exposure facilitates offensive aggression, in part by altering the development and activity of anterior hypothalamic arginine vasopressin (AH-AVP). This study assessed whether these effects were lasting by examining aggression and AH-AVP during AAS withdrawal. Adolescent hamsters administered AAS were tested as adults for aggression at 1, 4, 11, 18, or 25 days of withdrawal, sacrificed the following day, and examined for AH-AVP afferent innervation using immunohistochemistry. Through Day 12 of withdrawal, aggression and AVP were significantly higher in AAS-treated hamsters than in controls. These differences were no longer observable by Day 19 of withdrawal, at which point the behavior and neurobiology of AAS-treated hamsters reverted to that observed in controls. These data indicate that adolescent AAS exposure has short-term, reversible effects on both aggression and AH-AVP, correlating AH-AVP with the aggressive/nonaggressive behavioral phenotype during AAS withdrawal. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献