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991.
The transverse (T) tubules and the sarcoplasmic reticulum (SR) at the myotendinous junction of stretched rat skeletal muscle were examined by conventional and intermediate voltage electron microscopy. Stretching induced a large cytoplasmic space devoid of myofibrils at the ends of lengthening fibers. In this space, irregularly running tubular elements were seen. They were connected both with subsarcolemmal caveolae and with T tubules traversing to the A-I junctional level of the preexisting myofibrils. The SR was arranged at regular intervals which were narrower than those of the adult sarcomere. This orderly spacing of the SR seems to indicate that they may play some role(s) in myofibril assembly and/or T tubule arrangement. 相似文献
992.
K Iihara M Sasahara Y Saeki N Hashimoto H Kikuchi F Hazama 《Canadian Metallurgical Quarterly》1993,20(7-8):515-521
1. We characterized the endothelial cell-derived growth factors of SHRSP and Wistar Kyoto rats (WKY), respectively and found that platelet-derived growth factor (PDGF)-B chain related growth factor constituted a major portion of the mitogenic activity of the conditioned media of endothelial cells from both animals. There were no remarkable qualitative differences between the endothelial cell-derived growth factors of SHRSP and WKY. 2. Northern analysis revealed that the expression of PDGF-B chain was 2-4-fold enhanced in cultured aortic endothelial cells of SHRSP. This enhanced expression of PDGF-B chain, which may be induced under chronic hypertensive conditions, is suggested to contribute to the increase in endothelial cell-derived growth factors reported in this animal. 相似文献
993.
994.
Calculation of Mass Attenuation Coefficients of Beta Particles 总被引:1,自引:0,他引:1
Yi C.Y.; Han H.S.; Cho W.K.; Park U.J.; Jun J.S.; Chai H.S. 《Radiation protection dosimetry》1998,78(3):221-229
995.
Hepatic and pancreatic effects of polyenoylphosphatidylcholine in rats with alloxan-induced diabetes
V Buko O Lukivskaya V Nikitin Y Tarasov L Zavodnik A Borodinsky B Gorenshtein B Janz KJ Gundermann R Schumacher 《Canadian Metallurgical Quarterly》1996,14(2):131-137
In neonatally allylestrenol treated animals in adult age a single benzpyrene treatment significantly decreases the female and significantly increases the male rat's sexual activity. Three month old females display the negative sexual behavioral effect of neonatal allylestrenol treatment less than the six month old ones. The benzpyrene treatment in adult age decreases the sexual activity of male rats. The experiments call the attention to the modifying effect of perinatal steroid treatments to similar exposure in adult age. 相似文献
996.
We reported five patients with purple urine bag syndrome (PUBS). Four patients had indicanuria, and, in three of them, purple pigmentation was reproduced by inoculating urinary isolates, in the broth with indoxyl sulfate. Klebsiella pneumoniae, Pseudomonas aeruginosa and Enterococcus avium were considered to produce the purple pigment in three patients. However, attempts to reproduce the purple pigment failed in two patients, and one of them did not have indicanuria. These results suggest that indicanuria is not necessarily required for the development of PUBS. 相似文献
997.
R. Burlot R. Moncorgé H. Manaa G. Boulon Y. Guyot J. Garcia Solé D. Cochet-Muchy 《Optical Materials》1996,6(4):313-330
The polarized absorption and luminescence properties of Nd3+ doped isostructural LiNbO3, MgO:LiNbO3 and LiTaO3 nonlinear bulk single crystals are reported. Pump-probe experiments associated with the Judd-Ofelt approach are used to estimate two types of room temperature cross sections: polarized emission cross sections of the dominant 4F3/2 → 4I1//2 transition near 1085 and 1093 nm and polarized excited-state absorption cross sections in the same spectral domain and in the green spectral range corresponding to self frequency doubling. Self frequency-doubling results are also given in Nd:LiNbO3 and Nd:MgO:LiNbO3 versus sample temperature. 相似文献
998.
W. Liu K. M. Liang Y. K. Zheng J. Z. Cui 《Journal of Materials Science Letters》1996,15(15):1327-1329
999.
J. A. Xia H. T. Ren P. R. Munroe Y. Zhao H. K. Liu C. Andrikidis S. X. Dou 《Journal of Superconductivity and Novel Magnetism》1994,7(6):947-950
Silver has been previously added to the melt-textured YBa2Cu3O7?x in order to increase the critical current density (J c ) of these materials. However, the effect of this addition on theJ c is presently unclear. The purpose of this study is to investigate the effect of silver on both critical current density and the microstructure of the melt-textured YBa2Cu3O7?x superconductors by means of X-ray diffraction, optical polarized microscopy, and transmission electron microscopy (TEM). TheJ c of the MTG YBCO/Ag samples is more than 104A/cm2 under the 5 kOe magnetic field. It has been shown that as the concentration of silver increases, the fraction of the 211 phase dispersed within the 123 matrix decreases. Therefore, theJ c slightly decreases. These results, together with the effect of the 211 phase, dislocations, and other structure defects on flux pinning, are described in this paper. 相似文献
1000.
Circuit sensitivity to interconnect variation 总被引:1,自引:0,他引:1
Lin Z. Spanos C.J. Milor L.S. Lin Y.T. 《Semiconductor Manufacturing, IEEE Transactions on》1998,11(4):557-568
Deep submicron technology makes interconnect one of the main factors determining the circuit performance. Previous work shows that interconnect parameters exhibit a significant amount of spatial variation. In this work, we develop approaches to study the influence of the interconnect variation on circuit performance and to evaluate the circuit sensitivity to interconnect parameters. First, an accurate interconnect modeling technique is presented, and an interconnect model library is developed. Then, we explore an approach using parameterized interconnect models to study circuit sensitivity via a ring oscillator circuit. Finally, we present an alternative approach using statistical experimental design techniques to study the sensitivity of a large and complicated circuit to interconnect variations 相似文献