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1.
Erwan Stephan Stéphane Delanaud Cécile Bisch Jean-Pierre Libert Frédéric Telliez 《Journal of electromyography and kinesiology》2008,18(1):160-168
We present here a new, dedicated mechanical device for monitoring quick-release movements of the wrist. The ergometer was designed to easily assess musculotendinous properties during wrist flexion. Maximal voluntary contractions (MVC) and quick-release (QR) movements during wrist flexion were performed on 14 subjects. A validation of the ergometer, using a test-retest methodology, was performed to assess its reliability and sensitivity. The device has been technically and biomechanically validated in a range of situations, including inertia measurement (mean inertia was found 0.0119+/-0.0012 N m s(2) rad(-1)) and appearance of the unloading reflex. Our results indicate that the device provides highly reliable, sensitive evaluation of wrist muscle stiffness (intraclass correlation coefficient for inertia, maximal voluntary contraction and stiffness index were 0.873, 0.994 and 0.930, respectively). Its portability facilitates measurement of the influence of repetitive, occupational activity on the musculotendinous complex of the wrist flexors. 相似文献
2.
The infectivity and development of four populations of Meloidogyne hapla were compared, at three temperatures, on tomato and two varieties of cucumber. A population from Canada produced few root-galls on cucumber and, except at 24 C, no larvae developed into adult females and produced egg masses. In contrast, a population with 45 chromosomes from America produced many galls on cucumber and small proportions of larvae became females and produced egg masses at 20 and 24 C. At 18 C this population produced no egg masses on cucumber, but a population from Britain and one from America with 17 chromosomes produced more egg masses at this temperature than at 20 or 24 C. Dissection of the galls showed that on cucumber many larvae died or their growth and development was slowed. 相似文献
3.
By preparing a new experimental model for the carpal tunnel syndrome, the authors evaluated the differences of the human and rabbit carpal tunnels using a comparative anatomical study. A nearly identical situation-regarding the osseous and connective tissue formations in the carpal channel--was found. Therefore, the carpal tunnel of the rabbit is recommended for a model of chronic nerve compression, which is now planned by the authors. 相似文献
4.
S Matano G Baron H Stephan H D Frahm 《Folia primatologica; international journal of primatology》1985,44(3-4):182-203
Volumes of medial, interposed, and lateral cerebellar nuclei (MCN, ICN, and LCN) were measured in Insectivora, Scandentia, and Primates, including man. The relative size of the nuclei was expressed in size indices. Insectivora had by far the smallest cerebellar nuclei. The simians, in general, had larger cerebellar nuclei than the prosimians, but there was considerable overlap. From Insectivora to man, the MCN was the least progressive and the LCN the most progressive. The indices are expected to reflect the relative size of the three longitudinal zones of the cerebellum (vermis/MCN, pars intermedius/ICN, hemisphere/LCN). They, together with those of the ventral pons and cerebellum (part I), are discussed in relation to the predominant locomotor pattern of a species, and with reference to evolutionary trends in primate phylogeny. 相似文献
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Zusammenfassung Zellen des aus unreifen Plasmoblasten bestehenden, transplantablen KG 13-Plasmocytoms des Goldhamsters zeigen bei phasenoptischer Lebendbeobachtung in vitro ein besonders großes, stark strukturiertes Golgifeld. Dieses wird von einem Saum heller Pinocytosetröpfchen gegen die Speichergranula abgesetzt. Die Form des Golgifeldes, die Gesetzmäßigkeit seiner Veränderungen, die Spezifität seiner Strukturen und seine Beziehung zum Zellkern werden beschrieben. Pinocytosebläschen wandern bei dieser Zellart im gesamten Verlauf sichtbar von der Zellmembran zwischen den Speichergranula hindurch zur Randzone des Golgifeldes und lösen sich dort auf. Die Granula des Cytoplasmas entstehen offenbar im Golgifeld und werden in seiner Randzone erstmalig als solche erkennbar, um ins Cytoplasma zu wandern.
Die Arbeit wurde mit Unterstützung durch die Deutsche Forschungsgemeinschaft durchgeführt. 相似文献
Summary The KG 13 plasmocytoma from the Syrian golden hamster consists of immature Plasmoblasts. Living cells of this plasmocytoma observed by phase contrast microscopy in the hanging drop in vitro have a particularly large Golgi field surrounded by a border of light pinocytose bubbles. The cytoplasma is filled with storage granules. The form and the modifications of the Golgi field are described as well as his structure and his relations to the nucleus. Pinocytose bubbles reach the border of the Golgi field after crossing granules and disappeare. The granules are evidently formed in the Golgi field and become visible in its periphery.
Die Arbeit wurde mit Unterstützung durch die Deutsche Forschungsgemeinschaft durchgeführt. 相似文献
9.
Photomorphogenesis is a conspicuous feature in conifers. In the case of the shade-intolerant Scots pine (Pinus sylvestris L.), control of stem growth by light is well expressed at the seedling stage and can readily be studied. The present data show that hypocotyl growth is controlled by the far-red-absorbing form of phytochrome (Pfr). However, the Scots pine seedling requires blue or ultraviolet (UV-A) light to become fully responsive to Pfr. Blue/UV-A light has no direct effect on hypocotyl growth and its action appears to be limited to establishing the responsiveness of the seedling to Pfr. This type of coaction between phytochrome and blue/UV-A light has been observed previously in a number of angiosperm seedlings. With regard to the high irradiance reaction of phytochrome in long-term far-red light the pine seedling deviates totally from what has been observed in etiolated angiosperms since continuous far-red light has no effect on stem growth.Abbreviations B
light of wavelength between 500 and 400 nm
- FR
standard far-red light
- HIR
high irradiance reaction of phytochrome
- R
high-fluence-rate red light (R = 0.8)
- RG9-light
long-wavelength far-red light defined by the properties of the Schott RG9 glass filter (RG9<0.01)
- = Pfr/Ptot
wavelength-dependent photoequilibrium of the phytochrome system (far-red-absorbing form of phytochrome/total phytochrome)
- UV-A
near ultraviolet light of wavelength between 400 and 320 nm
- W
white light
Research supported by a grant from the Deutsche Forschungsgemeinschaft (Schwerpunkt Physiologie der Bäume). 相似文献
10.
Series (Fowler) dead space (VD) and slope of the alveolar plateau of two inert gases (He and SF6) with similar blood-gas partition coefficients (approximately 0.01) but different diffusivities were analyzed in 10 anesthetized paralyzed mechanically ventilated dogs (mean body wt 20 kg). Single-breath constant-flow expirograms were simultaneously recorded in two conditions: 1) after equilibration of lung gas with the inert gases at tracer concentrations [airway loading (AL)] and 2) during steady-state elimination of the inert gases continuously introduced into venous blood by a membrane oxygenator and partial arteriovenous bypass [venous loading (VL)]. VD was consistently larger for SF6 than for He, but there was no difference between AL and VL. The relative alveolar slope, defined as increment of partial pressure per increment of expired volume and normalized to mixed expired-inspired partial pressure difference, was larger by a factor of two in VL than in AL for both He and SF6. The He-to-SF6 ratio of relative alveolar slope was generally smaller than unity in both VL and AL. Whereas unequal ventilation-volume distribution combined with sequential emptying of parallel lung regions appears to be responsible for the sloping alveolar plateau during AL, the steeper slope during VL is attributed to the combined effects of continuing gas exchange and ventilation-perfusion inequality coupled with sequential emptying. The differences between He and SF6 point at the contributing role of diffusion-dependent mechanisms in intrapulmonary gas mixing. 相似文献