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291.
Antibody-decorated dystrophin molecule of murine skeletal myofiber as seen by freeze-etching electron microscopy 总被引:1,自引:0,他引:1
Dystrophin is the protein product of Duchenne muscular dystrophy gene which is defective in this genetic disorder. Here we identified ultrastructurally the dystrophin molecule from the various cytoskeletons at the cytoplasmic surface of murine myofiber plasma membrane by using quick-freeze, deep-etch, rotary-shadow replica of anti-dystrophin antibody-decorated muscle samples. The molecule was really cytoskeleton and incorporated in the meshwork of the plasma membrane-associated cytoskeletons. The molecule appeared to connect directly and/or through another cytoskeletal molecule with actin filament. 相似文献
292.
CMOS logic circuit optimum design for radiation tolerance 总被引:1,自引:0,他引:1
CMOS logic circuit optimum design for radiation tolerance has been investigated, based on NMOS and PMOS transistor parameter shift data due to radiation effects. The DC noise immunity for the three-input NAND has been found to be 36% greater than for the three-input NOR. The gate area for the optimised NAND is about three times smaller than that for the optimised NOR. 相似文献
293.
294.
K Takenaka H Gondo K Tanimoto K Nagafuji T Fujisaki S Mizuno T Miyamoto T Okamura S Hayashi T Eto K Osaki K Yamasaki T Shibuya N Harada T Teshima E Matsuishi T Minematsu Y Minamishima M Harada Y Niho 《Canadian Metallurgical Quarterly》1997,19(3):241-248
The purpose of this study was to identify correlates of physical activity behavior in a sample of rural, predominantly African American youth. Three hundred sixty-one fifth-grade students from two rural counties in South Carolina (69% African American, median age = 11 years) completed a questionnaire designed to measure beliefs and social influences regarding physical activity, physical activity self-efficacy, perceived physical activity habits of family members and friends, and access to exercise and fitness equipment at home. After school physical activity and television watching were assessed using the Previous Day Physical Activity Recall (PDPAR). Students were classified as physically active according to a moderate physical activity standard: two or more 30-min blocks at an intensity of 3 METs (metabolic equivalents) or greater, and a vigorous physical activity standard: one or more 30-min blocks at an intensity of 6 METs or greater. According to the moderate physical activity standard, 34.9% of students were classified as low-active. Multivariate analysis revealed age, gender, television watching, and exercise equipment at home to be significant correlates of low activity status. According to the vigorous physical activity standard, 32.1% of the students were classified as low-active. Multivariate analysis revealed age, gender, television watching, and self-efficacy with respect to seeking support for physical activity to be significant correlates of low activity status. In summary, gender and the amount of television watching were found to be the most important correlates of physical activity in rural, predominantly African American youth. 相似文献
295.
A parallel-two-wire-transmission-line covered by a three layer media has particular transmission characteristics. It is expected that this type of line might therefore be applied to new microwave circuits and antennas. Such lines have been analyzed by solving Laplace equations as a two dimensional boundary value problem. However, at higher frequencies, it is not appropriate to explain these particular properties using the quasi-TEM mode analysis. Transmission theory for these lines has to be solved using a rigorous three dimensional analysis. in this paper, we describe a new three dimensional analysis technique that is used to obtain more accurate propagation constants by considering the EZ, HZ components of the field. The assumed current distribution of the parallel-two-wire-line system is Fourier expanded over the angular coordinate &thetas;, and the boundary value problem is solved by the mode matching technique. It is found that mainly hybrid modes are transmitted via this type of transmission system and that the propagation constant varies discontinuously at frequencies where the dipole mode can exist on the three layer dielectric media itself. Numerical results are presented and compared with experimental data 相似文献
296.
297.
H Yamashita Y Ueta K Inenaga T Nagatomo I Shibuya N Kabashima LN Cui Z Li S Yamamoto 《Canadian Metallurgical Quarterly》1995,3(3-4):419-427
The hypothalamus is known to be an integrative site of cardiovascular, endocrine and autonomic functions. Our previous studies, using extracellular, intracellular and/or whole cell patch-clamp recordings in rat hypothalamic slice preparations, revealed that cardiovascular related peptides such as atrial natriuretic polypeptides (ANP), B-type polypeptides (BNP), endothelin (ET), angiotensin II (AII) and interleukin-1 beta (IL-1 beta) influence the hypothalamic neurons. ANP modulated the firing rates in the supraoptic nucleus (SON). BNP inhibited the SON neurons and these effects were mediated through cGMP and cGMP-dependent protein kinase. ET also inhibited approximately 60% of SON neurons. By using slice patch-clamp techniques, AII inhibited the transient outward potassium current in the SON neurons. IL-1 beta increased the firing rate and depolarized the membrane of the most SON neurons. A new type of transmitter, nitric oxide (NO), identified as an endothelial-derived relaxing factor (EDRF), modulated the glutaminergic inputs of the SON neurons. The results suggest that cardiovascular related peptides and NO modulate the neuronal activity of neurosecretory cells in the SON. 相似文献
298.
299.
Suzuki Kazuyoshi Shibuya Toshikazu Koizumi Takashi 《International Journal of Engineering Science》1978,16(10):707-715
This paper deals with the axially symmetric torsion of a hollow cylinder with an external crack. The mixed boundary value problem is reduced to a pair of dual series equations. These equations are shown to be equivalent to an infinite system of simultaneous equations. Numerical results are presented for stresses, displacement and stress intensity factors. 相似文献
300.
Shigeki Mori Masato Furuya Akihiro Naganawa Yotsugi Shibuya Goro Obinata Kazuhiro Ouchi 《Microsystem Technologies》2007,13(8-10):873-881
The nano-motion actuator (NMA) had been designed for precise track following on a spin-stand which evaluated read and write performance of a high-density magnetic recording. A required specification of the original NMA was a resonance frequency of over 5 kHz and working distance of over 10 μm. However, according as industrial researches of the perpendicular magnetic recording progress, a phenomenon that is called WATER (Wide Area Track ERasure) should be evaluated on the spin-stand. Since required working distance to evaluate the WATER reaches to over 50 μm, an X–Y stage on the spin-stand was cooperated with the NMA, as usual. However, the piggyback system which combined the X–Y stage with the NMA could not observe the WATER phenomenon continuously on a disk medium. Therefore, a new NMA which had a large working distance of over 50 μm was required. The new NMA was designed and simulated several resonance modes by using 2D or 3D of EFM analysis. The new actuator called as NMA-k501 realized the working distance of 43.3 μm and the resonance frequency of 5.33 kHz with a mechanical damper. As wide servo bandwidth was reached to 2.75 kHz to apply a PID controller, clear and sharp step responses could be showed at a 1 and a 10 nm, respectively. Furthermore, when precise positioning stability was evaluated, the NMA-k501 was positioning within 0.101 nm at 3σ. 相似文献