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81.
82.
A network-theoretic approach to the design of a dynamic precompensator C (s ) for a multiinput, multioutput plant T (s ) is considered. The design is based on the relative degree of each element of T (s ). Specifically, an efficient algorithm is presented for determining whether a given plant T (s ) has a diagonal precompensator C ( s ) such that, for almost all cases, T (s )C (s ) has a diagonal interactor. The algorithm also finds any optimal precompensator, in the sense that the total relative degree is minimal. The algorithm can be easily modified to work even when a T (s ) represented by a nonsquare matrix is given 相似文献
83.
Intracytoplasmic sperm injection (ICSI) and partial zona dissection followed by insemination (PZD-I) were used to establish a microinjection system in cynomolgus monkeys (Macaca fascicularis), which are potential models for human reproduction. Two experimental systems were studied, in which either hamster oocytes or cynomolgus monkey oocytes were used as the vehicle. When hamster oocytes were used, 66 out of 81 ICSI-treated oocytes (82%) showed sperm head swelling or pronucleus formation. Following PZD-I of hamster oocytes the rates of spermatozoa penetration (85/114; 75%) and fertilization (71/114; 62%) were relatively high. When cynomolgus monkey oocytes were used, 19 out of 31 (61%) were fertilized by ICSI with cynomolgus monkey spermatozoa and, subsequently, two embryos (7%) developed to the morula stage. In total, 94% (15/16) of the PZD-I treated oocytes were penetrated by spermatozoa and 63% (10/16) were fertilized. These results demonstrate that both micromanipulation techniques can be used in assisted fertilization with cynomolgus monkeys. 相似文献
84.
BACKGROUND: To assess the role of contrast enemas for the evaluation of leaks in symptomatic and asymptomatic patients after the first stage of restorative proctocolectomy. METHODS: We reviewed the findings of 59 contrast enemas in 40 patients who underwent total proctocolectomy with creation of an ileoanal pouch and a proximal diverting ileostomy. Thirty-seven patients initially underwent routine contrast studies of the ileoanal pouch, and three underwent contrast studies because of suspected fistulas or obstruction. Medical records were also reviewed to determine the clinical presentation and course of these patients. RESULTS: Of 37 patients who underwent routine postoperative contrast enemas, 33 (89%) had normal studies, three (8%) had clinically silent leaks (including two blind-ending tracks from the ileoanal anastomosis and one from the pouch), and one (3%) had pouchitis. In all three patients with unsuspected leaks, ileostomy closure was delayed. In two other patients with abdominal pain and fever, contrast enemas revealed leaks from the ileoanal pouch and distal ileum, respectively. The remaining patient had a contrast enema because of abdominal pain and distention; this patient had a distal ileal obstruction due to adhesions. CONCLUSIONS: Routine postoperative contrast studies revealed clinically silent leaks from the ileal J pouch or ileoanal anastomosis in three of 37 patients (8%) after the first stage of restorative proctocolectomy. Our findings suggest that routine contrast enema can detect clinically silent leaks after this surgery. 相似文献
85.
Hayakawa H. Yoshikawa N. Yorozu S. Fujimaki A. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2004,92(10):1549-1563
Single-flux quantum logic (SFQ) circuits, in which a flux quantum is used as an information carrier, have the possibility for opening the door to a new digital system operated at over 100-GHz clock frequency at extremely low power dissipation. The SFQ logic system is a so-called pulse logic, which is completely different from the level logic for semiconductors like CMOS, so circuit design technologies for SFQ logic circuits have to be newly developed. Recently, much progress in basic technologies for designing SFQ circuits and operating circuits at high speeds has been made. With advances in these design tools, large-scale circuits including more than several thousand junctions can be easily operated with the clock frequency of more than several tens of gigahertz. High-end routers and high-end computers are possible applications of SFQ logic circuits because of their high throughput nature and the low power dissipation of SFQ logic. In this paper, recent advances of SFQ circuit design technologies and recent developments of switches for high-end routers and microprocessors for high-end computers that are considered possible applications for SFQ logic will be described. 相似文献
86.
K Yoshikawa K Iwamoto E Sugimoto Y Takanashi K Nakajima 《Canadian Metallurgical Quarterly》1997,37(6):500-505
We report a 42-year-old left-handed woman with congenital right hemiparesis and bilateral mirror movements in the hands. She had a porencephaly of the left hemisphere and the brain MRI demonstrated cortical and subcortical defect of the left hemisphere from Brodmann's area 6 to 40 including the left motor cortex. By electrical stimulation of the left median nerve at the wrist, N20 of the somatosensory evoked potential was recorded in the right postcentral gyrus by using the dipole tracing method. Long-loop reflexes from the bilateral thenar muscles were recorded and their latencies were almost the same. The stimulation of the right median nerve did not evoke N20, nor long-loop reflex. These electrophysiological findings suggest that the reorganization of the motor system made the right motor cortex to innervate bilateral hands, and caused bilateral mirror movements. In other words, the mirror movements managed to relieve the paralysis of the right hand though the damage of the left motor cortex was present. In the previous literature we are able to find hypotheses regarding the mechanism of mirror movements in congenital hemiparesis. Here we discussed about the reorganization of the motor system in the damaged brain. 相似文献
87.
K Yoshikawa Y Suzaki M Tanaka S Arihara SK Nigam 《Canadian Metallurgical Quarterly》1997,60(12):1269-1274
Four new oleanane-type triterpene glycosides, pithedulosides H-K (1-4), were isolated from the seeds of Pithecellobium dulce. Their structures were established by extensive NMR experiments and chemical methods. Compounds 1-3 comprised acacic acid as the aglycon and either monoterpene carboxylic acid and its xyloside or monoterpene carboxylic acid as the acyl moiety at C-21. The oligosaccharide moieties linked to C-3 and C-28 were determined as alpha-L-arabinopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1 -->6)- [beta-D-glucopyranosyl-(1-->2)]-beta-D-glucopyranosyl and alpha-L-arabinofuranosyl-(1-->4)-[beta-D-glucopyranosyl-(1-->3)]-alpha- rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl ester, respectively. Compound 4 was established as an echinocystic acid 3-O-glycoside having the same sugar sequences as 1-3. Also obtained in this investigation was the known compound 5, which was identified as echinocystic acid 3-O-beta-D-xylopyranosyl- (1-->2)-alpha-L-arabinopyranosyl-(1-->6)-[beta-D-glucopyranosyl-(1 -->2)]- beta-D-glucopyranoside. 相似文献
88.
T Gabata O Matsui M Kadoya K Ueda Y Kawamori J Yoshikawa K Nobata Y Fujinaga T Matsuoka T Takashima 《Canadian Metallurgical Quarterly》1997,22(5):502-505
BACKGROUND: Aberrant gastric venous drainage (AGVD) into the posterior edge of the medial segment of the liver (segment IV) is the main cause of pseudolesion on computed tomography (CT) during arterial portography. We estimated the prevalence of AGVD into the medial segment of the liver with color and power Doppler ultrasound (US). METHODS: Screening gray-scale and color Doppler and power Doppler US were performed in 100 consecutive patients. AGVD was defined as a venous structure that ascended parallel to the main portal vein and drained independently into segment IV. RESULTS: AGVDs were observed in eight of 100 patients (8%) with color and power Doppler US. Power Doppler US depicted these veins more clearly than did color Doppler US. Gray-scale US did not show any AGVDs. Two of eight patients with AGVDs detected by color Doppler US underwent celiac arteriography and CT during arterial portography (CTAP). In these two patients, celiac arteriography directly demonstrated AGVDs draining into segment IV, which revealed nontumorous perfusion defects (pseudolesions) on CTAP. CONCLUSION: Color and power Doppler US are useful imaging methods for demonstrating AGVDs. 相似文献
89.
K Noguchi N Yoshikawa S Ito-Kariya Y Inoue Y Hayashi H Ito H Nakamura K Iijima 《Canadian Metallurgical Quarterly》1998,9(10):1815-1825
Vascular permeability factor (VPF), also known as vascular endothelial growth factor (VEGF), is a multifunctional cytokine involved in angiogenesis, inflammation, and wound healing. Although VPF/VEGF has been reported to be produced only by glomerular podocytes in glomeruli, it was found that it is produced by human cultured mesangial cells (MC). Therefore, immunohistochemical analysis (using indirect immunofluorescence and in situ hybridization) of VPF/VEGF in normal kidneys (n = 7) and biopsy specimens taken from 83 patients with renal diseases, including mesangial proliferative glomerulonephritis (PGN) (n = 58), was performed to examine whether VPF/VEGF is produced by MC in human PGN. In all of the healthy subjects and all of the patients except those with PGN (disease control subjects), VPF/VEGF protein and mRNA were detected mainly in podocytes. However, in some PGN patients, VPF/VEGF protein was demonstrated clearly in MC as well as in podocytes, as some of the VPF/VEGF was colocalized with alpha-smooth muscle actin, a marker of activated MC, and VPF/VEGF mRNA was expressed by MC and podocytes. Mesangial VPF/VEGF expression level increased significantly in PGN patients with early lesions (P < 0.01 versus healthy subjects or disease control subjects, P < 0.05 versus PGN with later lesions). The time between biopsy and disease onset was significantly shorter in PGN patients with than in those without mesangial VPF/VEGF expression (P < 0.01). These findings provide the first evidence that activated MC are a source of VPF/VEGF in human PGN, and indicate that mesangial VPF/VEGF expression is characteristic of early lesions of PGN. Because VPF/ VEGF plays a pivotal role in tissue repair, MC-produced VPF/VEGF may play pathophysiologic roles, including promoting recovery from glomerular injuries, in early-stage PGN. 相似文献
90.
K O'Hara J Chen F Shigenobu A Nakamura K Taniguchi M Shimojima H Ida E Yoshikawa I Tsuboi K Mizuoka T Sawai 《Canadian Metallurgical Quarterly》1998,95(381):109-115
Among recent clinical isolates in Japan, strain CU264 was discovered which formed unusual colonies. This strain was identified as Rahnella aquatilis which is usually found in water. The antibiotic susceptibilities against tetracycline, carbenicillin, chloramphenicol, streptomycin, kanamycin, gentamicin, sulphonamide, neomycin, fosfomycin, rifampicin, norfloxacin and nalidixic acid, were investigated. The result demonstrated that the strain was highly resistant to fosfomycin only. It was further shown that this resistance was transmissible with low frequency to Serratia marcescens whereas it was not transmissible to Escherichia coli. 相似文献