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61.
Objective: To determine whether “low‐intensity” exercise (walking) and “high‐intensity” exercise (aerobic dance), when added to a weight loss diet, have different effects on coronary heart disease (CHD) risk factors and physical fitness. Research Methods and Procedures: Ninety obese women were divided into diet only (DO), diet plus walking (DW), and diet plus aerobic dance (DA) groups. DXA was used to evaluate segmental body composition. Leg‐extension strength and maximal oxygen uptake (V?o 2max) were the indicators of physical fitness. Blood pressure, lipoproteins, and fasting glucose were used as indices for CHD risk factors. These items were measured before and after a 14‐week intervention period. Results: Whole‐body plus all segmental fat masses were significantly reduced (p < 0.001). Reductions in whole‐body and lower‐limb fat‐ and bone‐free masses were significantly less (p < 0.01) in the DA group (?1.5 and ?0.1 kg, respectively) compared with the DO (?2.1 and ?0.4 kg, respectively) and DW (?2.5 and ?0.5 kg, respectively) groups. Improvements in leg‐extension strength and V?o 2max were significantly greater (p < 0.05) in the DA group compared with the DO group. The CHD risk factors clearly improved (p < 0.05) within each group. Reductions in low density lipoprotein‐cholesterol and fasting glucose were significantly greater (p < 0.05) in the DA group compared with the DO and DW groups. Discussion: Adding higher intensity aerobic dance to a weight‐loss diet program may help maintain fat‐ and bone‐free mass and may be more effective in improving CHD risk factors compared with low‐intensity walking.  相似文献   
62.
In developing chick leg buds, large-scale cell death occurs in the interdigital zone, which is responsible for the separation of digits from each other. Ectopic cartilage formation is known to occur upon removal of the chondrogenic digit tissue of the leg bud. To examine the mechanisms of ectopic cartilage formation in the interdigital cell death region, we performed the following operations on stage 28–29 leg buds: (i) removal of the digit-forming area; (ii) incision between the interdigital zone and digit region; (iii) insertion of an aluminum barrier into the interdigital zone; and (iv) insertion of a permeable Nuclepore filter into the interdigital zone. In all cases, the inhibition of cell death and/or the formation of ectopic cartilage in the interdigital zone were observed, although the frequency of the inhibition of cell death and the formation of ectopic cartilage varied, depending upon the position where the operations were performed. These results suggest that cell death and cell differentiation in the interdigital zone may be controlled by some factor(s) from digit cartilage.  相似文献   
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64.
We examined retention of butt-end aluminum leg bands on Rio Grande wild turkeys (Meleagris gallopavo intermedia) captured in Texas and Kansas, USA, 2000–2009. We examined 187 recaptured or harvested radiotagged wild turkeys to determine band retention and modeled band retention with Program MARK. We did not detect differences in band retention among age and gender classes or that band retention probability was time dependent. We estimated monthly probability of band retention was 0.990 (SE = 0.002). Band retention probability was 0.971 (SE = 0.006) at 3 months post-banding and 0.864 (SE = 0.028) at 15 months post-banding. Butt-end aluminum leg band retention was not 100% for wild turkeys marked during our work; however, our band retention rates were 3.7–5.7 times greater than described previously. © 2011 The Wildlife Society.  相似文献   
65.
The feral Cat (Felis catus) population on Macquarie Island was targeted for eradication between 1996 and 2002, with 761 cats captured during this period. After 22 years of cat control from 1974 integrated with control programmes for other pests, effort intensified for 2 years before a dedicated eradication programme began in 1998. The primary knock‐down for the eradication used cage trapping and shooting, with most surviving cats captured with leg‐hold traps. A total of 6298 field days and 216 574 trap nights were recorded in this operation. Factors contributing to the success of the programme included extensive planning, increased staff numbers at critical times, better access to remote areas of the island, introduction of leg‐hold traps, sufficient operational funding and good collaboration between government agencies operating on the island. The programme would have benefited from earlier deployment of detector dogs and better posteradication monitoring of a broader range of native species impacted by cats. The successful eradication of cats from Macquarie Island, being the second largest achieved to date, provides valuable experience for cat eradication attempts on other large remote islands. This programme relied on ground‐based techniques with minimal use of poisons and provides possible options for sites where broad‐scale poisoning, or where aerial distribution of poisons, cannot be used.  相似文献   
66.
Swimming crabs of the taxon Portunoidea show specialized, paddle-shaped fifth pereiopods (P5), which play a role in these crabs' ability to swim. In this study, the morphology of the fifth pereiopod in swimming and non-swimming crabs was studied in detail and the mobility in the articulations between podomeres was calculated from reconstructed three-dimensional (3D)-models. This way, we aimed to provide new estimates of kinematic parameters, and to answer the question on a possible homology of the P5 within several portunoid clades. We measured and compared podomere length ratios, orientations of the joint axes, and modeled single range of motion ( sROM ) of each joint as well as the total range of motion ( tROM ) of all joints of the P5 as a whole. Seven Portunoidea species, four of them belonging to the P5-swimming crab morphotype (Liocarcinus depurator, Polybius henslowii, Callinectes sapidus, Portunus pelagicus) and three not belonging to this morphotype (Carcinus aestuarii, Portumnus latipes, and with uncertain status Carupa tenuipes) were compared with the non-portunoids Sternodromia monodi, Ranina ranina, Raninoides bouvieri, Eriocheir sinensis, Varuna litterata, Ashtoret lunaris, and Cancer pagurus. The study was carried out using a combination of microcomputer tomography (μCT)-techniques and 3D-reconstructions. The μCT-data were used to create surface models of the P5 in Amira, which were then 3D-animated and manipulated in Maya to qualitatively compare modeled kinematic parameters. Results show that the merus and carpus in swimming crabs are shorter than in non-swimming crabs, while sROM angles are generally larger. The tROM of all joints expressed as Euclidean distances is generally higher in the portunoids (except for Carcinus). Our comparison of the complete trajectory of the dactylus tip regarding all maximum joint positions of the studied species suggests that the P5-swimming leg might have evolved once in the Portunoidea and got lost afterward in certain clades.  相似文献   
67.
IntroductionThe aim of this study was to determine the within- and between-day reliability of lower limb biomechanical variables collected during single leg squat (SLS) and single leg landing (SLL) tasks.Methods15 recreational athletes took part in three testing sessions, two sessions on the same day and another session one week later. Kinematic and kinetic data was gathered using a ten-camera movement analysis system (Qualisys) and a force platform (AMTI) embedded into the floor.ResultsThe combined averages of within-day ICC values (ICCSLS = 0.87; ICCSLL = 0.90) were higher than between-days (ICCSLS = 0.81; ICCSLL = 0.78). Vertical GRF values (ICCSLS = 0.90; ICCSLL = 0.98) were more reliable than joint angles (ICCSLS = 0.85; ICCSLL = 0.82) and moments (ICCSLS = 0.83; ICCSLL = 0.87).DiscussionThis study demonstrates that all joint angles, moments, and vertical ground reaction force (GRF) variables obtained during both tasks showed good to excellent consistency with relatively low standard error of measurement values. These findings would be of relevance to practitioners who are using such measures for screening and prospective studies of rehabilitative techniques.  相似文献   
68.
心电标测是心脏电生理机理研究的主要方法,也是临床精密诊断和对心律失常病灶进行精确定位的重要手段,特别适用于房颤等复杂心律失常电生理机制的研究.该文主要介绍了心外膜电位标测系统中的前置放大模块的设计,并根据实际需要,增加了右腿驱动电路.通过人体与动物实验检测,应用右腿驱动电路后均能得到清楚的心电波形.  相似文献   
69.
In research regarding postural stability, leg preference is often tested and controlled for. However, leg preference may vary between tasks. As athletes are a group of interest for postural stability testing, we evaluated the effect of five leg preference tasks categorization (step up, hop, ball kick, balance, pick up) on single-leg postural stability of 16 field hockey athletes. The ‘center of pressure speed’ was calculated as the primary outcome variable of single-leg postural stability. Secondary variables were ‘mean length of the GRF vector in the horizontal plane’, ‘mean length of the ankle angular velocity vector’, and ‘mean length of the hip angular velocity vector’, as well as the separate outcomes per degree of freedom. Results showed that leg preference was inconsistent between leg preference tasks. Moreover, the primary and secondary variables yielded no significant difference between the preferred and non-preferred legs, regardless of the applied leg preference task categorization (p>0.05). The present findings do not support the usability of leg preference tasks in controlling for bias of postural stability. In conclusion, none of the applied leg preference tasks revealed a significant effect on postural stability in healthy field hockey athletes.  相似文献   
70.
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