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101.
传承、弘扬和培育优良的大学精神,是现代大学共同面临的现实间题。笔者从现代大学精神的内涵和基本功能的阐释入手,提出了现代大学精神的本质。在此基础上,分析了现代大学精神缺失的表象,进而提出要树立新的理念重构现代大学精神。  相似文献   
102.
不同鹿胎及胎盘制剂对老年雄性大鼠免疫机能影响的研究   总被引:3,自引:1,他引:3  
研究了鹿胎及胎盘制剂对老年雄性大鼠免疫器官指数、血清球蛋白含量和巨噬细胞吞噬率及吞噬指数的影响。结果表明,鹿胎及胎盘制剂对老年雄性大鼠胸腺和脾脏指数影响不显著(P>0.05);但提高了老年雄性大鼠血清球蛋白含量,其中鹿胎制剂Ⅰ号组最高,比对照组高出62.64%,与其他各组相比有显著差异(P<0.05);鹿胎制剂Ⅱ号组和人胎盘粉处理组大鼠巨噬细胞吞噬率和吞噬指数与对照组相比有极显著提高(P<0.01),说明鹿胎及胎盘制剂对老年雄性大鼠具有提高免疫机能的作用。  相似文献   
103.
The aim of this study was to research the population structure and genetic diversity of the Nova Scotia Duck Tolling Retriever (NS) and the Lancashire Heeler (LH) dog breeds. Data consisted of nearly all the worldwide registration history for both breeds, including 28 668 NS and 4 782 LH individuals. A reference population, including the females born between 1999 and 2008, was defined for genetic analyses for each breed. Average depth of the pedigrees known for the reference population dogs was 12.9 complete generation equivalents in the NS and 6.0 in the LH. Only a small fraction of the born dogs were used later for breeding. Effective number of founders was 9.8 in the NS and 15.2 in the LH. More than 50% of the genetic diversity in the reference population was explained by two ancestors in the NS and five in the LH. Average inbreeding coefficients in the reference populations were 0.26 in the NS and 0.10 in the LH. Average kinships were 0.26 and 0.08 and realised effective population sizes 18 and 28, respectively. Failure to use available genetic resources for sustainable breeding has resulted in depletion of genetic variation in both breeds. To increase genetic variation, a larger proportion of the dogs should be used in reproduction and the contributions of reproducing animals should be equalized. In the LH, it is necessary to use the unregistered farm dogs in breeding. In the NS, crosses with another breed are needed.  相似文献   
104.
ObjectiveTo determine the analgesic and systemic effects of epidural administration of ketamine, lidocaine or a combination of ketamine/lidocaine in standing cattle.Study designProspective, randomized, experimental trial.AnimalsSix healthy male cattle weighing between 335 and 373 kg.MethodsThe animals received 0.5 mg kg?1 of ketamine (K), 0.2 mg kg?1 of 2% lidocaine (L) or 0.25 mg kg?1 ketamine plus 0.1 mg kg?1 lidocaine (KL). All the drugs were injected into the dorsolumbar epidural space via a caudal approach through a non‐styletted multiple‐port catheter. Each animal received each treatment at random. Evaluations of analgesia, sedation, ataxia, heart rate, arterial pressure, respiratory rate, skin temperature and rectal temperature were obtained at 0 (basal), 5, 10, 15, 30, 45, 60, 75, 90 minutes after epidural injection, and then at 30‐minute intervals until loss of analgesia occurred. Skin temperature was taken at these intervals up to 60 minutes. All the animals received a standard noxious stimulus; a 4‐point scale was used to score the response. A second scale was used to score ataxia and a third for sedation.ResultsThe duration of analgesia in the upper and lower flanks in cattle was 140 ± 15, 50 ± 14 and 80 ± 22 minutes (mean ± SD) after dorsolumbar epidural KL, K or L, respectively. The cardiovascular changes were within acceptable limits in these clinically healthy cattle.ConclusionsDorsolumbar epidural administration of KL to cattle resulted in longer duration of analgesia of the upper and lower flanks in standing conscious cattle, than the administration of K or L alone.Clinical relevanceFurther research is necessary to determine whether this combination using this technique provides sufficient analgesia for flank surgery in standing cattle.  相似文献   
105.
西部农村饲草资源充裕,发展奶牛养殖小区有利于减少草料运输费用,有利于减轻城郊养牛环境污染,有利于改善牛奶质量。本文提出小区建设应注意的五个问题:注重奶牛质量;采用胚胎移植技术,提高小区牛群的个体产奶量:种养结合,建立与奶牛养殖业配套的饲草生产基地;改进饲养管理,推行混合日粮饲养技术;实行行业准入制度,控制小区环境污染,提高牛奶质量,生产绿色奶品。  相似文献   
106.
Unexpected adverse preclinical findings (APFs) are not infrequently encountered during drug development. Such APFs can be functional disturbances such as QT prolongation, morphological toxicity or carcinogenicity. The latter is of particular concern in conjunction with equivocal genotoxicity results. The toxicologic pathologist plays an important role in recognizing these effects, in helping to characterize them, to evaluate their risk for man, and in proposing measures to mitigate the risk particularly in early clinical trials. A careful scientific evaluation is crucial while termination of the development of a potentially useful drug must be avoided. This first part of the review discusses processes to address unexpected APFs and provides an overview over typical APFs in particular classes of drugs. If the mode of action (MoA) by which a drug candidate produces an APF is known, this supports evaluation of its relevance for humans. Tailor-made mechanistic studies, when needed, must be planned carefully to test one or several hypotheses regarding the potential MoA and to provide further data for risk evaluation. Safety considerations are based on exposure at no-observed-adverse-effect levels (NOAEL) of the most sensitive and relevant animal species and guide dose escalation in clinical trials. The availability of early markers of toxicity for monitoring of humans adds further safety to clinical studies. Risk evaluation is concluded by a weight of evidence analysis (WoE) with an array of parameters including drug use, medical need and alternatives on the market. In the second part of this review relevant examples of APFs will be discussed in more detail.  相似文献   
107.
五种牧草及三种草坪草种子寄藏真菌检测初探   总被引:4,自引:0,他引:4  
龚月娟  李健强 《草业学报》2004,13(5):116-120
采用PDA平皿法和滤纸法检测了市售5个牧草品种和3个草坪草品种种子样品寄藏真菌的情况,并就分离获得的真菌对种子出苗及幼苗生长的影响进行了初步研究.结果表明,供试种子样品带菌率为0~70.5%,分离获得的35个真菌分离物大多属于镰刀菌(Fusarium spp.)、链格孢菌(Alternaria spp.)、蠕孢菌(Helminthosporium spp.)、小核菌(Sclerotium sp.)、匍柄霉菌(Stemphylium spp.)和曲霉菌(Aspergillus spp.).供试样品中假俭草和波多马各(鸭茅)种子带菌率较高,在PDA平皿检测中其未经表面消毒处理的种子带菌率分别为48.4%和70.5%,表面消毒处理种子带菌率分别为40.8%和28.8%,分离获得的种子寄藏真菌对假俭草和波多马各种子出苗及幼苗生长的影响较小.圣地亚哥(南苜蓿)和菊苣种子带菌率较低,但分离获得的真菌对其种子出苗和幼苗生长的影响较大.以镰刀菌与匍柄霉菌接种过的南苜蓿种子出苗率分别比未经表面消毒且未接种真菌的对照低44.0%和21.7%,出苗后的病苗率分别为22.7%和29.7%;以链格孢菌与曲霉菌接种过的菊苣种子的出苗率分别比未经表面消毒且未接种真菌的对照低22.0%和27.5%,出苗后的病苗率分别为2.3%和29.3%.  相似文献   
108.
从北京两个主要牛场共采得187头中国荷斯坦奶牛的血样,提取基因组DNA,通过PCR-RFLP方法对Kappa酪蛋白、Beta乳球蛋白(βlg)和Alpha乳白蛋白(α-la)进行了基因型的鉴定,并结合产奶性状进行统计分析,结果表明,牛群中上述3种乳蛋白基因的基因频率分别为K-cnA79%,K-caB21%,β-lgA43%,β-lgB57%,α-lgB100%,K-CN和β-lg基因位眯对产奶量没  相似文献   
109.
通过克隆的家蚕核多角体病毒解旋酶基因DNA与重组救活可线性化的苜蓿尺蠖核多角体病毒基因工程载体病毒 (BacPAK6 )DNA在昆虫细胞中发生重组 ,经累代筛选获得了既可感染家蚕又可感染秋粘虫细胞Sf 2 1的宿主域扩大的昆虫杆状病毒表达载体 (HyBacPAK6 )。HyBacPAK6DNA经Bsu36Ⅰ酶切后与含植酸酶基因的转移载体pVL1393 phy在家蚕细胞中重组后 ,通过蓝白斑筛选发现重组率可达 90 %以上。然而以杂交病毒为载体的外源基因表达量仅为以BmNPV为载体病毒的表达量的 2 0 %左右。分析认为HyBacPAK6可用于表达一些对蚕体有害的外源基因。  相似文献   
110.
星星草对碱化土壤物理性质的影响   总被引:17,自引:2,他引:17  
孙国荣  阎秀峰  李晶 《草地学报》2002,10(2):118-123
研究不同生长年限的星星草对碱化土壤及对应碱斑土壤的机械组成、土壤孔隙度、容重和含水量的影响。结果表明,星星草生长1、2和3年后,粘粒和细砂所占比例减小,而粗粉和细粉所占比例增大。土壤总孔隙度、毛管孔隙度和非毛管孔隙度随着生长年数的增加呈不同程度的增加,而土壤容重则越来越小,>0.25mm的水稳定性团聚体随之增加。星星草地土壤含水量和田间持水量均高于碱斑土壤。星星草改善了碱化土壤结构、通透性、保水性和土壤物理环境。  相似文献   
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