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901.
902.
903.
Masaki Ishikawa Paavo V Komi Taija Finni Sami Kuitunen 《Journal of electromyography and kinesiology》2006,16(5):423-431
When the prestretch intensity and concentric work are increased in stretch-shortening cycle (SSC) exercises, the utilization of the elastic energy can increase during the concentric phase. In order to further understand this process during SSC exercises, the interaction between fascicle-tendinous tissues (TT) of the vastus lateralis (VL) muscle was examined under different prestretch and rebound intensity drop jumps. Ten male subjects participated in the study. Direct VL fascicle lengths (N = 10) and in vivo patellar tendon force (N = 1) were measured together with the electromyographic (EMG) activity of VL during the trials. With increasing drop height but the same rebound height condition, the TT stretch increased during the early braking phase with a subsequent increase in its recoil during the early push-off phase. This occurred concomitantly with decreased fascicle shortening and EMG activation. However, with the increased rebound height but the same drop height condition, the fascicles were stretched less during the late braking phase with higher EMG activation. In this situation, TT could be stretched more by the tension provided by fascicles. Consequently, the TT recoil increased during the late push-off phase. These observations confirm that there can be an intensity specific fascicle-TT interaction during SSC exercises. 相似文献
904.
Asuman Gölgeli Nurcan Dursun Cem Süer Çigdem özesmi Sami Aydogan 《Biological trace element research》1997,60(3):251-260
The effect of zinc ions on the isometric contraction of rat diaphragm muscles in the presence and in the absence of external
calcium was studied. Using a transducer, the isometric force was measured as a function of supramaximal electrical stimulation,
either directly or indirectly applied to the muscle. The following parameters were measured: peak twitch tension, PT, twitch
contraction time, CT, relaxation half-time, RT-1/2, and peak rates of tension increase and decrease, +dP/dt and -dP/dt. The
following zinc-induced alterations were observed: an increase of the PT; a decrease of the RT-1/2; an increase in the +dP/dt
and -dP/dt. The CT was not changed significantly. Our results suggest that zinc ions have a positive inotropic effect on isolated
diaphragm muscle. The increase in PT may be explained by a zinc-activated Ca2+ uptake by sarcoplasmic reticulum. This was followed by an increase in the rate of rise of tension development, which was
secondary to increased -dP/dt. The mechanism(s) by which extracellular Ca2+ contributes to this action of zinc is not known. 相似文献
905.
The frequency of isoniazid slow inactivators is very high among Eqyptians, 82% have more than 0.91 γ/ml of free INH in serum specimens obtained six hours after a single dose of 10 mgm/kgm. The incidence of the allele for INH acetylase enzyme deficiency is estimated at 0.9059 and that of the heterozygous carrier of this allele at 0.1705. 相似文献
906.
Localization of VIP-immunoreactive nerves in airways and pulmonary vessels of dogs,cats, and human subjects 总被引:1,自引:0,他引:1
Summary VIP-containing neurons were localized in lungs from dogs, cats, and human subjects by means of the indirect immunofluorescence technique. Nerve fibers and terminals were observed in the smooth muscle layer and glands of airways, and within the walls of pulmonary and bronchial vessels, especially at the medial-adventitial junction. VIP-positive nerve cell bodies were identified in ganglia located in the walls of bronchi. These findings provide an anatomic basis for the possible modulation of airway and pulmonary vascular function by this neuropeptide.Supported by National Research Service Award HL 5914 and by Lung Center Award HL 14187 from NHLBI, USPHS 相似文献
907.
Jukka Bisi Sami Kurki Marko Svensberg Tuija Liukkonen 《European Journal of Wildlife Research》2007,53(4):304-314
The growth of the Finnish wolf (Canis lupus) population during the last years has highlighted people’s contradictory attitudes toward wolves. The supranational conservation
objectives brought on by Finland’s membership in the European Union (EU) and the regional application of the official policy
on wolves have led to conflicts. This article is based on the preparation process of the wolf management plan in Finland.
As a part of the process, a nationwide hearing was arranged in 2004. Fear of wolves is widespread and even more common in
areas with low wolf population. People living in areas where wolves occur feel that they can no longer influence decision
making which affects them and that the authorities, conservationists, and the EU do not listen to their opinions. Numerous
requests have been made for the legislation and its interpretation, and concessions to these requests would promote consensus
and increase tolerance for wolves. Proposed changes include reforming the damage compensation system and formulating a clearer
interpretation of the conservation status of wolves. However, it seems impossible to create a policy that would be universally
supported. As the wolf question has become more central in environmental policy, the conservation and management of the species
have become more complicated, and the cooperation between various interest groups has declined. The wolf conflict could be
mitigated by compromises, but because the conflict is value-based, solutions are illusive. 相似文献
908.
The stem barks of Oricia renieri and O. gabonensis have yielded nine alkaloids, including furoquinolines, acridones, 3,4-pyrano-2-quinolones and a 2-amino-benzophenone. One of the pyranoquinolones isolated from O. renieri, 7-methoxy-N-methylflindersine, is reported for the first time. All alkaloids were identified on the basis of spectral data. The chemotaxonomic significance of the alkaloids of these two species is discussed. 相似文献
909.
910.
Sami Ahmad Chris A. Pritsos Ronald S. Pardini 《Archives of insect biochemistry and physiology》1990,15(2):101-109
The black swallowtail butterfly, Papilio polyxenes, larvae are specialized feeders of pro-oxidant rich plants of Apiaceae and Rutaceae. An important defense against toxic forms of oxygen species generated by ingestion of the pro-oxidants, are the antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT), GSH-dependent glutathione peroxidases (selenium-dependent glutathione peroxidase [GPOX] and peroxidase activity of selenium-independent glutathione-S-transferase [GTpx]), and glutathione reductase (GR). The subcellular distribution of these enzymes in black swallowtail larvae was investigated and was found to resemble the patterns described for larvae of two other lepidopteran species: the southern armyworm, Spodoptera eridania, and the cabbage looper, Trichoplusia ni. The confinement of SOD in the cytosol and mitochondria was typically eukaryotic, but the relative proportion (1:1) was markedly different from the mammalian pattern (4:1; cytosol:mitochondria). The most obvious difference between the black swallowtail and other lepidoptera as a group, and mammalian species, is in very wide intracellular distributions of CAT, GTpx, and GR in insect species. Insects possess very low levels of a GPOX-like activity which reduces both H2O2 and organic peroxides. Consequently, insects have elaborate activities with a wide subcellular distribution of both CAT which decomposes H2O2, and GTpx which decomposes organic peroxides. The reduction of peroxides is dependent on GSH, which in this process is oxidized to GSSG. GR which reduces GSSG to GSH is also of wide subcellular distribution, analogous to the distribution pattern of GTpx. 相似文献