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51.
52.
王凤 《吉林农业科技学院学报》2013,(3):69-71
张家山汉墓竹简刊发以来,学术界便掀起了对其研究的热潮,近些年来,关于张家山汉简的研究取得了丰硕的成果,其中在法律思想、制度方面的成果最为突出,同时在研究方法上也有所突破,但相关的语言研究却很滞后. 相似文献
53.
Rumesh Ranjan Ashish Kumar Swarupa Nanda Mandal 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(7):588-595
ABSTRACT Nitrogen uptake being part of nitrogen use efficiency (NUE) is largely decided by root traits. Root traits variability has hardly been explored by breeders mainly because of difficulties in scoring. The hydroponic system requiring lesser space for precise phenotyping of large numbers of genotypes independently of the growing season can be a suitable alternative. However, the effectiveness of hydroponic screening methods needs to be verified under the soil condition of the field or pot. In the present study, root traits and NUE were investigated in 19 genotypes under two conditions (hydroponic and pipe filled with soil). Both environments revealed large variability for root traits and NUE under high and low N conditions establishing the absence of any direct selection for these traits in the past. Under both sets of experimentation, NUpE was largely responsible for improved nitrogen efficiency mainly because of higher root biomass. The significant association between the two screening methods i.e. hydroponic and pot filled with soil under both low and high N condition support large scale screening for root traits under hydroponic condition. 相似文献
54.
20世纪20年代末30年代初,中国历史上形成了一次大规模的"乡村建设运动"。作为"足以代表这个运动的整个方面之较早者"——中华职业教育社"鉴于农村的衰落,与一般农业学校造就的人材,不合实际的需要,并且不能担当挽救农村衰落的重任,主张改变方向,把职业教育的范围扩大,深入到农村里去",(1)积极投入到乡村建设运动中,在长江三角洲地区展开了一系列的乡村建设活动。 相似文献
55.
The productivity and financial performance of dairy farms in New Zealand and Japan (Hokkaido) were analyzed. By recomposing the official statistics on the dairy industry relative to Japan, New Zealand has low milk yield productivity per cow, but higher per hectare performance because of their seasonal breeding and pasture grazing systems. In the revenue and expenses analysis, New Zealand had a high cash surplus ratio compared with Hokkaido. In the cost analysis, for expenses on a “per kg of raw milk” basis, New Zealand milk production costs are 29% of those in Hokkaido. More than 60% of the production costs were attributable to feed, interest charges and wages in New Zealand. In Hokkaido, the feed cost alone accounted for 73% of the total cost. There is also a remarkably high interest expenditure in New Zealand caused by non‐subsidized fund procurement from finance organizations. In the financial analysis, New Zealand dairy farms have only approximately 50% of the total assets per cow compared with farms in Hokkaido. But total liabilities per cow in Hokkaido are twofold to threefold greater than in New Zealand. The difference between total assets and total liabilities shows that Hokkaido dairy farmers have an equity that is 50–200% greater than New Zealand dairy farmers. In the management analysis, New Zealand has a low turnover ratio of gross assets caused by the seasonal breeding system. In conclusion, New Zealand has higher per hectare production performance than Hokkaido, but has a low utilization of gross assets caused by a seasonal breeding system based on pasture grazing. 相似文献
56.
Pedersen HD Häggström J Falk T Mow T Olsen LH Iversen L Jensen AL 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1999,13(1):56-64
Observer variation in diagnosing mild mitral regurgitation in dogs by cardiac auscultation was assessed by having 6 veterinarians with different levels of experience examine 57 Cavalier King Charles Spaniels. Comparisons with color Doppler echocardiography and phonocardiography were made, and the effects of 2 physical maneuvers on the auscultatory findings were evaluated. Using mildly diseased dogs, interobserver agreement in diagnosing the presence or absence of left-sided murmurs ranged from 63% to 88%. The agreement with phonocardiography (range, 53-91%) increased with the amount of observer experience. The 2 most experienced observers could discern soft ejection murmurs from regurgitant murmurs and were able to diagnose 89% of the dogs with regurgitant jets larger than 30% of the left atrial area. In general, less experienced observers diagnosed most jets larger than 50%. In many dogs with small jets, no murmur was found by auscultation and phonocardiography. The audibility of mild regurgitation was significantly reduced in dogs that were difficult to auscultate. Early systolic murmurs were typical of mild regurgitation, whereas holosystolic murmurs typified severe regurgitation. In a few dogs, late systolic murmurs alternated with holosystolic murmurs. Systolic clicks were found phonocardiographically in 18 dogs with mild to moderate regurgitation, but the audibility apparently was low. In many mildly affected dogs, physical maneuvers increased murmur intensity. Thus, some form of dynamic auscultation might facilitate the diagnosis of mild regurgitation. Auscultatory findings in mild regurgitation appear to depend on observer experience, circulatory status, and how difficult the dog is to auscultate. 相似文献
57.
58.
Gene Wunderlich 《Agriculture and Human Values》2002,19(1):81-85
The American Country LifeAssociation was heir to Theodore Roosevelt'sCountry Life Commission, which examined thegeneral conditions of farming life in the opencountry, and...its larger problems. In1919, Kenyon Butterfield, a member ofRoosevelt's Commission, met withrepresentatives from 30 states and 25 nationalorganizations to form the American Country LifeAssociation. In that year, Butterfield, ACLA'sfirst president, published a book, TheFarmer and the New Day, whose defining chapterwas The Making of Communities: The CommunityIdea. The ACLA was educator created and led.Solutions to rural problems were seen aseducational matters. But educational philosophywas undergoing scrutiny and new educationalconcepts were arising from the bustling,industrializing, urbanizing times of late19th century. The experimental,unconstrained spirit of the nation at the turnof the century was formalized as pragmatism. Aleading pragmatist and educator of the time wasJohn Dewey, a contemporary of Butterfield.The communitarianism of Butterfield and Deweycarried throughout the life of ACLA in avariety of forms. Even after ACLA ended as anorganization in 1976, the concerns and idealscontinued in successor organizations, and canbe found in environmental, sustainableagriculture, and rural life organizationstoday. This paper traces one of continuingthemes of the ACLA, the community idea as a wayof adding a social dimension to agriculture'seconomic policies and development. The ACLAstory is a metaphor for country life throughmuch of 20th century America. ACLA is alsoa lesson in how organizations come into being,flourish, falter, die, and leave their legaciesto future generations. 相似文献
59.
本文主要对麦盖提羊体重与脂肪指标的相关性进行研究分析,并对体重与尾脂重.网油重和肾油重的相关性进行研究分析,认为麦盖提羊活重与胴体重.胴体重与尾脂重,网油重和肾油重之间有不同程度的正相关关系,周岁公母羊活重与胴体重的相关系数分别为0.914和0.997胴体重与尾脂重的相关系数分别为0.56和0.75而且差异极显著.成年公母羊胴体重与尾脂重的相关系数分别为0.73和0.70而且差异极显著.同时指出降低油脂含量和尾脂比重的具体做法,这对麦盖提羊现代育种提供科学的依据. 相似文献
60.
Prognostic significance of serum alkaline phosphatase activity in canine appendicular osteosarcoma 总被引:3,自引:0,他引:3
Garzotto CK Berg J Hoffmann WE Rand WM 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2000,14(6):587-592
Sixty-one dogs with appendicular osteosarcoma were treated with amputation and chemotherapy of cisplatin and doxorubicin. Serum samples were obtained before and after treatment for determination of total alkaline phosphatase (TALP) activity as well as the activities of the constituent bone (BALP), liver (LALP), and corticosteroid-induced (CALP) isoenzymes. The relationship between alkaline phosphatase activities and survival was examined by Cox proportional hazards regression analysis and Kaplan-Meier log rank analysis. Mean activity of TALP, BALP, and LALP decreased significantly after treatment (P < .001). TALP and LALP activities before treatment were significantly correlated with survival (P = .006 and .001, respectively). The correlation between BALP activity before treatment and survival approached significance (P = .054). CALP activity and TALP, BALP, and LALP activities after treatment were not significantly correlated with survival. Dogs with normal pretreatment TALP and BALP activities survived significantly longer than dogs with increased pretreatment activities (P = .001 and .003, respectively). Median survival times for dogs with normal or increased TALP activities before treatment were 12.5 and 5.5 months, respectively; and median survival times for dogs with normal or increased BALP activities before treatment were 16.6 and 9.5 months, respectively. In the design of future clinical trials involving dogs with osteosarcoma, consideration should be given to stratifying the randomization according to alkaline phosphatase activity. In addition, alkaline phosphatase activity should be a factor considered by clinicians attempting to tailor the aggressiveness of adjuvant chemotherapy to the needs of individual patients or owners. 相似文献