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S Goto T Kondo T Negoro RL Boyd IL Nielsen T Lizuka 《Canadian Metallurgical Quarterly》1996,110(5):490-501
The influence of mandibular growth on the stability of orthodontic treatment has been well established. A particular problem is late mandibular growth in patients with Class III malocclusions, because of skeletal jaw discrepancies that may influence the timing and course of treatment, as well as the stability of posttreatment. We have used the ossification of the distal phalanx of the first digit as an indicator of the skeletal maturity of the patient and of their potential for further growth. Our previous studies have shown that fusion of the epiphysis and the diaphysis of the distal phalanx of the first digit occurs from 1 to 3 years after the pubertal growth maximum in Japanese women. In these case reports, the orthodontic treatment of two female patients with mild Class III skeletal malocclusions is presented to show the possible clinical application of the ossification of the first digit as an indicator of the completion or near cessation of mandibular growth in the timing of treatment of Class III malocclusions. The case reports show that, although both patients experienced some mild degree of mandibular growth after treatment, this method can be helpful in determining residual mandibular growth potential in Japanese female patients with Class III malocclusions and mild skeletal discrepancies. 相似文献
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This study set out to examine in detail the distribution of axons of sympathetic non-noradrenergic neurons innervating the arterial bed in skeletal muscles of the forelimb and hindlimb of guinea-pigs. The distribution of non-noradrenergic axons with immunoreactivity to vasoactive intestinal peptide (VIP) was examined in limb muscles of different histochemical character. The immunohistochemical demonstration of myosin heavy chain from fast-twitch muscle, and the histochemical demonstration of adenosine triphosphatase and succinic dehydrogenase, were used to determine the muscle fibre profile of 6 different limb muscles. Muscles included the oxidative type I muscle fibre-rich accessory semimembranosus muscle, the predominantly glycolytic type II muscle fibre-rich cranial gracilis and biceps brachii muscles and the plantaris, gastrocnemius medial head and triceps brachii long head of mixed muscle fibre composition. The frequency with which the VIP-immunoreactive (VIP-IR) axons innervated intramuscular arterial vessels was compared between categories of muscles defined by their muscle fibre profile. This study demonstrated that the projection of non-noradrenergic sympathetic neurons to skeletal muscle vasculature was widespread in guinea-pig limb muscles, but that it was not uniform. VIP-IR axons were more likely to innervate the arterial vasculature of muscles with a high proportion of type I and/or oxidative muscle fibres than of muscles with a large proportion of type IIb muscle fibres. This relationship between the distribution of sympathetic non-noradrenergic axons and the metabolic characteristics of muscle suggests that these presumed vasodilator neurons have an important role in matching blood flow to the particular metabolic demands of different limb muscles. 相似文献
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The latest results of influences of physical training during pregnancy on the foetus are presented. In humane, no pathological effects on the embryogenesis have been demonstrated. During exercise, a modest increase (5-25 bpm) in foetal heart rate is a common finding. This might be caused by reduced oxygen supply to the foetus, but could more likely be due to stimuli from vasoactive hormones or training-induced uterine contractions. Foetal growth seems to be influenced by maternal training, as moderate training has resulted in significantly bigger babies compared to both inactivity and hard training. In one study it was shown that low body weight in babies from hard-training mothers was due to reduced neonatal fat mass. Pathological sequelae due to increased maternal temperature during training have not been found in humans. The results strongly suggest that moderate training during pregnancy can be recommended if simple precautions are taken. 相似文献
367.
DL Baker K Hashimoto IL Grupp Y Ji T Reed E Loukianov G Grupp A Bhagwhat B Hoit R Walsh E Marban M Periasamy 《Canadian Metallurgical Quarterly》1998,83(12):1205-1214
Cardiac hypertrophy and heart failure are known to be associated with a reduction in Ca2+-ATPase pump levels of the sarcoplasmic reticulum (SR). To determine whether, and to what extent, alterations in Ca2+ pump numbers can affect contraction and relaxation parameters of the heart, we have overexpressed the cardiac SR Ca2+-ATPase specifically in the mouse heart using the alpha-myosin heavy chain promoter. Analysis of 2 independent transgenic lines demonstrated that sarco(endo)plasmic reticulum Ca2+-ATPase isoform (SERCA2a) mRNA levels were increased 3.88+/-0. 4-fold and 7.90+/-0.2-fold over those of the control mice. SERCA2a protein levels were increased by 1.31+/-0.05-fold and 1.54+/-0. 05-fold in these lines despite high levels of mRNA, suggesting that complex regulatory mechanisms may determine the SERCA2a pump levels. The maximum velocity of Ca2+ uptake (Vmax) was increased by 37%, demonstrating that increased pump levels result in increased SR Ca2+ uptake function. However, the apparent affinity of the SR Ca2+-ATPase for Ca2+ remains unchanged in transgenic hearts. To evaluate the effects of overexpression of the SR Ca2+ pump on cardiac contractility, we used the isolated perfused work-performing heart model. The transgenic hearts showed significantly higher myocardial contractile function, as indicated by increased maximal rates of pressure development for contraction (+dP/dt) and relaxation (-dP/dt), together with shortening of the normalized time to peak pressure and time to half relaxation. Measurements of intracellular free calcium concentration and contractile force in trabeculae revealed a doubling of Ca2+ transient amplitude, with a concomitant boost in contractility. The present study demonstrates that increases in SERCA2a pump levels can directly enhance contractile function of the heart by increasing SR Ca2+ transport. 相似文献
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BACKGROUND: Pseudomonas aeruginosa with inhibitory capacity in vitro was studied on Gardnerella vaginalis strains. METHODS: Antimicrobial activity was demonstrated by inhibitory halos of bacterial growth on solid media by two methods: crossed streak and agar well diffusion. The inhibitory activity of this substance produced by P. aeruginosa was characterized as bacteriocin by: activity spectrum sensitivity proteolytic enzyme, chloroform, heat, pH, ultraviolet, irradiation effect and molecular weight. RESULTS: Four strains of P. aeruginosa producers of bacteriocins were chosen for this study and contacted with 40 strains of G. vaginalis. The producing strain D inhibited 70% of these G. vaginalis strains. The strains B and C inhibited 55% and 52.5%, respectively. The 3 strains presented a wide rank of action but the strain A had effect on a few strains of G. vaginalis. CONCLUSIONS: This work showed the inhibitory in vitro effect of bacteriocins of P. aeruginosa on strains of G. vaginalis. The results obtained suggest the probable topic application of bacteriocins as an alternative of conventional therapeutic on this infection biological control. 相似文献