摘要：选用21±1日龄、平均体重405.23±80.56g的新西兰白兔96只,按完全随机区组设计分为4组,每组24只(公母各半),研究日粮中分别添加0%、0.05%、0.10%和0.20%的L-丙氨酰-L-谷胺酰胺对21～35日龄仔兔生长性能的影响。结果表明:仔兔日粮中添加0.05%～0.20%L-丙氨酰-L-谷胺酰胺可提高断奶仔兔日增重(P<0.05),降低仔兔腹泻率,提高饲料报酬。第0～7d各试验组增重均显著高于对照组,平均日增重分别比对照组高出62.06%、60.93%、62.19%(P<0.01);第7～14d,试验组的增重效果与对照组相比未体现出优势。试验期试验Ⅰ组、试验Ⅱ组的增重成本分别比对照组降低19%和6%,试验Ⅲ组增重成本比对照组高出42.4%。综合增重、腹泻发生率和增重成本,L-丙氨酰-L-谷胺酰胺的适宜添加量为0.05%～0.1%。

摘要：为达到林木速生丰产的目的,而采用高度集约的营林措施,是当前林业发展的趋势,为了进一步了解和明确针阔混交林在本地区的生长效应,以及由于受树种生物学特性和林地土壤养分条件差异影响,不同阔叶树与针叶树混交生长效应不一至,因此为探讨选择合理的阔叶树种与针叶树种混交,提高林分的生长抗性及营林效益,达到事半功倍的目的,为此我场于1993年在管店林场进行马尾松与阔叶树(枫香、麻栎)混交试验,以马尾松纯林作为对照区。经过14年观察试验,混交林及马尾松纯林生长效应优劣明显,现将试验结果总结如下:1试验方法1.1试验地概况试验地设置在管店林场14林班16、17两小班,林地为丘陵岗地,海拔78m左右,年平均降水量为972·5mm,年平均气温15度。千枚岩黄棕壤,土壤厚度在30-60cm,pH值为6·7,肥力一般。该地为1992年马尾松采伐迹地。1.2试验设计本试验采用8马2栎、8马2枫两种带状混交方式及对照区马尾松纯林作为不同的处理,每个处理重复两次,试验面积25亩。2营林管理2.1造林造林前采用明穴整地,穴规格为50×50×30cm,株行距1·0×1·5m,每亩445株,于1993年3月选用马尾松、枫香、麻栎等一级苗造林,严把造...

摘要：Objective: Our objective was to determine whether slow fetal growth rates and twin growth patterns from 20 weeks’gestation to delivery are associated with very preterm delivery. Study design: Available charts were reviewed for twin pregnancies, delivered between 1979 and 2002, at 4 U.S. medical centers. The sample of 1612 pregnancies delivered at 28 week’s gestation or greater and had at least 2 ultrasound evaluations of fetal size from 20 to 28 weeks or from 28 weeks to delivery for estimation of fetal growth rates (grams per week). Slow fetal growth (below the 10th percentile) was defined as less than 90 grams per week at 20-28 weeks and 168 g/week from 28 weeks to delivery. The main outcome measure was the timing of delivery. Results: Of the women delivering twins, 5.3%delivered extremely preterm (28-30 weeks), 8.5%very preterm (31-32 weeks), and 40.1%preterm (33-36 weeks). Patterns of growth for the pair were highly associated with very preterm delivery. Compared with neither growing slowly (1.7%), 4.9%delivered very preterm if only 1 twin grew slowly. Very preterm was 14.6%(adjusted odds ratio 9.81; 95%confidence interval, 3.50-27.48) with both growing slowly from 28 weeks on and 20.0%(adjusted odds ratio 15.04; 95%confidence interval 5.13-44.11) with both growing slowly over both intervals. Survival analyses indicated that twins with normal growth in both intervals remained undelivered for a significantly longer number of days (P < .0001) than pairs in which one or both twins were growing slowly. Conclusion: Very preterm delivery of twins seems to be preceded by slowed or compromised fetal growth for the pair.

摘要：红松、杉木、楠木是大自然中间常见的3种树。3种树材质不同，生长速度也不同，用途也不尽相同。

摘要：21世纪,全球城市化进程加速,愈趋现代化的都市同时遭受人工造物"全新式样永久性垃圾"对自然景观的破坏,材料和工艺流程选择对住民赖以生存的空气的污染。如何逆转都市混乱状况?作壁上观还是从眼前的设计做起?美国设计理论家维克多·帕帕奈克认为,设计师要站出来为混乱都市担责;建立理想的生态城市,从建设一个好的设计生态开始。

摘要：在探究根生长方向的实验中选用菜豆、黄豆、小麦、玉米等材料进行实验，结果这些材料的根系不发达，生长缓慢，且根系较软，从培养基质中取出后生长方向性不明显，实验效果不理想。后来选用大蒜作实验材料，其优点是根生长速度快，且一旦根向一个方向生长再从培养基中取出，根系定型好，实验效果明显。

摘要：豆芽菜是一种生长速度极快的植物,一夜之间便能长六七厘米,且外表看起来壮硕饱满,然而众所周知,在快速生长的同时,豆芽莱的质地非常脆弱,稍遇外力便会折断。在一些发展快的新兴行业,如互联网、IT、游戏动漫业,一些新员工受重用快速升迁,其自身能力却无法胜任新职位。

摘要：言几又 言几又取自繁体字“設”。言,即语言、沟通方式;几,即差异、别致;又,即多元递进。言几又文化集团创立于2006年,是一个以实体文化空间为载体,集合生活方式、多元业态、文化资源的平台。2006年,言几又的前身“今日阅读”诞生,那时还主营书籍和杂志,后来逐渐尝试多元化经营,倡导业态融合理念,希望彼此突破与超越独立单向的板块,共同建构基于相同的创意语言而碰撞形成的城市文化空间。