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We describe the physiological characteristics of amateur outrigger canoe paddlers. Twenty-one paddlers (13 males, 8 females) were evaluated for body stature, aerobic power, muscular strength and endurance, peak paddle force, flexibility and 250 m sprint paddle performance at the end of the outrigging season. The mean variables (+/- s) for the males were: age 27 +/- 9 years, height 175 +/- 5 cm, body mass 80 +/- 5 kg, arm span 178 +/- 7 cm, sitting height 100 +/- 2 cm, aerobic power 3.0 +/- 0.4 l x min(-1), maximum bench press strength 85 +/- 19 kg, right peak paddle force 382 +/- 66 N and left peak paddle force 369 +/- 69 N. For the females, these were: age 26 +/- 6 years, height 168 +/- 5 cm, body mass 70 +/- 8 kg, arm span 170 +/- 5 cm, sitting height 97 +/- 3 cm, aerobic power 2.3 +/- 0.51 l x min(-1), maximum bench press strength 47 +/- 10 kg, right peak paddle force 252 +/- 63 N and left peak paddle force 257 +/- 60 N. Analysis of variance revealed differences (P < 0.05) between the dominant and non-dominant sides of the body for peak paddle force, isokinetic internal and external rotation, and flexion and extension torque of the shoulder joint. The outrigger canoe paddlers were generally within the range of scores found to describe participants of other water craft sports. Outrigger canoeists should be concerned with the muscular strength imbalances associated with paddling technique.  相似文献   
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可持续农业     
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Copy number variants (CNVs) are pieces of genomic DNA of 1000 base pairs or longer which occur in a given genome at a different frequency than in a reference genome. Their importance as a source for phenotypic variability has been recognized only in the last couple of years. Chromosomal deletions can be seen as a special case of CNVs where stretches of DNA are missing in certain lines when compared to the reference genome of the mouse line C57BL/6, for example. Based upon more than 8 million single nucleotide polymorphisms (SNPs) in the fifteen inbred mouse lines which were determined in a whole genome chip based resequencing project by Perlegen Sciences, we detected 20166 such long chromosomal deletions. They cover altogether between 4.4 million and 8.8 million base pairs, depending on the mouse line. Thus, their extent is comparable to that of SNPs. The chromosomal deletions were found by searching for clusters of missing values in the genotyping data by applying bioinformatics and biostatistical methods. In contrast to isolated missing values, clusters are likely the consequence of missing DNA probe rather than of a failed hybridization or deficient oligos. We analyzed these deletion sites in various ways. Twenty-two percent of these deletion sites overlap with exons; they could therefore affect a gene's functioning. The corresponding genes seem to exist in alternative forms, a phenomenon that reminds of the alternative forms of mRNA generated during gene splicing. We furthermore detected statistically significant association between hundreds of deletion sites and fat weight at the age of eight weeks.  相似文献   
45.
This prospective study examined the effects of maternal characteristics, social support, and risk factors on infant-mother attachment in a heterogeneous sample. Two hundred and six women between the ages of 18 and 40 were interviewed during their last trimester of pregnancy and 1 year postpartum. Structural equation modeling revealed that maternal attachment experiences were significantly related to prenatal representations of the infant and of the self as a mother, which were significantly related to infant-mother attachment assessed by the Strange Situation. Maternal risk factors were significantly related to prenatal representations, and social support from other women predicted infant-mother attachment. The overall model indicated a good fit. Thus, both individual and contextual factors were important in explaining infant attachment security.  相似文献   
46.
传统的临床试验方法可能延误救命治疗方法的利用,目前食品药物管理局的管理人员正在试图使速度与误差的风险相平衡。  相似文献   
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太阳能     
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48.
NONLINEAROPTICSINQUANTUMWIRES¥ChenRei-min(DepartmentofPhysicsandAstronomy,StateUniversityofNewYorkatBuffaloBuffalo,NewYork142...  相似文献   
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基因疗法     
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