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排序方式: 共有3046条查询结果,搜索用时 15 毫秒
941.
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提高大学生心理健康教育实效性的关键问题是找准切入点,即从大学生感到最敏感、最脆弱、最需要、最关心、最欠缺、最容易出偏差等对心理健康影响最大的内在因素入手,选择相应的教育目标、教育内容和教育方法,只有这样才能达到促进大学生的心理成长,维护大学生心理健康的终极目的。本文从大学生心理健康教育的实践出发,基于对影响大学生心理健康教育实效性的因素分析,提出了有利于提高大学生心理健康教育实效性的五个切入点:一是以培养自信为切入点,引导大学生构建健康的自我意识;二是以阳光心态塑造为切入点,引导大学生提升情绪管理能力;三是以人格完善为切入点,引导大学生强化人际交往能力;四是以职业生涯规划为切入点,引导大学生确立合理的成才目标;五是以生命教育为切入点,引导大学生追求积极健康的人生意义。 相似文献
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Early prediction of water-holding capacity in meat by multivariate vibrational spectroscopy 总被引:3,自引:0,他引:3
This study had the dual purpose of (a) investigating the feasibility of measuring fundamental vibrational information in fresh porcine meat using infrared (IR) absorption and Raman scattering, and (b) investigating if the vibrational spectra obtained within 1 h after slaughter contained information about the water-holding capacity (WHC) of the meat. Preliminary studies performed at a research slaughterhouse revealed a high correlation between WHC and both IR (r=0.89) and Raman spectra using Partial Least Squares Regressions (PLSR). The good results were confirmed under industrial conditions using FT-IR at-line spectroscopy. However, the latter experiment yielded a somewhat lower correlation (r=0.79). This result is, however, promising for the purpose of finding a method for classification of carcasses with regard to WHC at the slaughter line. The IR region 1800-900 cm(-1) contains the best predictive information according to WHC of the porcine meat. This region covers functional group frequencies of water, protein, fat and glycogen, including the carbonyl and amide groups. 相似文献
946.
Khaitsa ML Kegode RB Bauer ML Gibbs PS Lardy GP Doetkott DK 《Journal of food protection》2007,70(2):476-481
Salmonella is one of the most frequent causes of foodborne illness worldwide, and transmission involves foods of animal origin such as beef. The objective of this study was to monitor the prevalence of Salmonella fecal shedding in feedlot cattle during the finishing period and to assess the antimicrobial resistance patterns of the isolated salmonellae. On arrival at the feedlot, 1 (0.7%) of the 144 steers was shedding Salmonella in its feces. After 28 days on feed, shedding was detected in 8 (5.6%) of the 144 steers. At the third sampling, 19 (13%) of 143 steers were shedding, and the number of shedders continued to increase to 89 (62%) of 143 at the last sampling. Salmonella shedding was significantly influenced (P < 0.0001) by sampling time but not by herd of origin. All Salmonella isolates identified belonged to serotype Typhimurium serovar Copenhagen, a type commonly isolated from Salmonella infections in humans. Antimicrobial resistance testing of the isolates revealed five multidrug resistance patterns, two of which accounted for 104 (95.4%) of 109 of the isolates. All the isolates were susceptible to ceftiofur, and all were resistant to spectinomycin, sulfathiazole, tiamulin, florfenicol, ampicillin, penicillin, chlortetracycline, oxytetracycline, and clindamycin. Data from this study indicate that a high prevalence of antimicrobial-resistant Salmonella strains can sometimes be found in feedlot cattle in North Dakota. These data will contribute to risk assessment of Salmonella shedding by cattle in feedlots and highlight the need to continue preharvest monitoring for this organism. 相似文献
947.
目的:为市售豆奶粉中镍污染风险防控提供技术支撑。方法:以浓硝酸为消解液,利用超级微波消解进行前处理,以铑元素作为内标物消除基质干扰,在动能甄别模式(KED)下利用电感耦合等离子体质谱法测定豆奶粉中镍元素的含量,并对超级微波消解条件与ICP-MS工作条件进行了优化。结果:该方法的标准曲线在0~10 μg/L的质量浓度范围内线性关系良好,相关系数为0.999 9,检出限为0.002 mg/kg,加标回收率为94.5%~100.6%,相对标准偏差为1.8%~2.3%;用豆奶粉中镍质控样(ZKQC5210)对该方法进行准确性验证,结果在证书标定范围内。结论:该方法准确可靠,适用于豆奶粉中镍含量的测定。 相似文献
948.
Effects of diet and injection of bovine somatotropin on prepubertal growth and first-lactation milk yields of Holstein cows 总被引:1,自引:0,他引:1
Radcliff RP Vandehaar MJ Chapin LT Pilbeam TE Beede DK Stanisiewski EP Tucker HA 《Journal of dairy science》2000,83(1):23-29
To determine effects of rapid prepubertal growth on first-lactation milk production, Holstein heifers were randomly assigned to one of three treatments. Thirty-five heifers were fed a standard diet to meet NRC recommendations and produce 0.8 kg of body weight (BW) gain/d (standard). Thirty-five heifers were fed a diet with higher energy (2.8 Mcal of metabolizable energy/kg) and protein (19.7% crude protein; high diet) to produce 1.2 kg of BW gain/d (high). Thirty-five heifers were fed the high diet and injected daily with bovine somatotropin (bST) (25 microg/kg of BW; high-bST). Diets were fed and bST was injected from 135 kg of BW until pregnancy was confirmed. Heifers were inseminated after BW exceeded 363 kg. Pregnant heifers were commingled and fed similar diets through gestation, parturition, and lactation. High and high-bST heifers had greater prebreeding average BW gains than standard heifers. Conversely, standard heifers had a greater average BW gain during gestation than high and high-bST heifers. High and high-bST heifers were approximately 90 d younger than standard heifers at first insemination and first parturition. Postpartum BW, body condition scores, and withers heights at parturition, and calving ease scores were not different among treatments. Standard heifers produced 14% more milk than high heifers but not more than high-bST heifers. The high-protein, high-energy diet decreased age at first parturition and first-lactation milk production, but did not affect reproduction. Injection of bST during the prepubertal growth period combined with the high diet decreased age at first parturition without reducing milk production. 相似文献
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