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81.
Tsukude M. Kuge S. Fujino T. Arimoto K. 《Solid-State Circuits, IEEE Journal of》1997,32(11):1721-1727
A charge-transfer presensing scheme (CTPS) for 0.8-V array operation with a 1/2 Vcc bit-line precharge achieves a five times larger readout voltage and 40% improvement in sensing speed compared with conventional sensing schemes. Operation over a 1.2- to 3.3-V range is achieved. A nonreset row block control scheme (NRBC) for power-consumption improvement in data-retention mode is proposed which decreases the charge/discharge number of the row block control circuit. By combining CTPS and NRBC, the data-retention current is reduced by 75% 相似文献
82.
Y Kuroda Y Tanioka A Morita K Hiraoka S Matsumoto Y Fujino K Yamamoto Y Ku Y Saitoh 《Canadian Metallurgical Quarterly》1994,57(5):658-661
Rewarming ischemia during implantation severely compromises posttransplant pancreas graft survival because the graft has already been subjected to warm and cold ischemia before implantation. The purpose of this study was to examine whether preservation of the pancreas graft by the two-layer method ameliorates rewarming ischemic injury of the graft during implantation using a canine model. After flushing with cold University of Wisconsin solution (UW), the pancreas grafts were preserved by the two-layer (UW/perfluorochemical [PFC]) method (group 1) or simple cold storage in UW (group 2) for 24 hr and then autotransplanted. In control, the pancreas grafts were flushed out with cold UW and immediately autotransplanted without preservation (group 3). After completion of vascular anastomosis, vascular clamp was not released until 90, 120, or 150 min of rewarming ischemia, including anastomosis time, had elapsed. After 90 min of rewarming ischemia, graft survival rates were 5/5, 100%, 5/5, 100%, and 5/5, 100%, in groups 1, 2, and 3, respectively. After 120 min, all the grafts in groups 2 and 3 failed (0/5, 0%, and 0/5, 0%, respectively); however, all the grafts in group 1 survived (5/5, 100%). Even after 150 min, 1 of 3 grafts in group 1 survived (1/3, 33%). After 24 hr preservation, tissue ATP levels of the grafts in group 1 were about 2-fold the reference values before harvesting (8.23 +/- 0.72 vs. 4.44 +/- 0.49 mumol/g dry weight, P < 0.05) and significantly higher compared with group 2 (8.23 +/- 0.72 vs. 1.76 +/- 0.52 mumol/g dry weight, P < 0.01). After 120 min of rewarming ischemia, tissue ATP levels in group 1 were 84% of the reference values and significantly higher compared with group 2 (3.75 +/- 0.25 vs. 1.57 +/- 0.48 mumol/g dry weight, P < 0.05). Two hours after reperfusion, ATP levels in group 1 were 42% of reference values but significantly higher compared with group 2 (1.86 +/- 0.36 vs. 1.03 +/- 0.18 mumol/g dry weight, P < 0.05). We conclude that the two-layer (UW/PFC) method ameliorates rewarming ischemic injury of the pancreas graft during implantation by increasing tissue ATP contents during preservation and consequently maintaining tissue ATP levels during implantation. 相似文献
83.
EE Calore MJ Cavaliere NM Perez V Takayasu A Wakamatsu MH Kiss 《Canadian Metallurgical Quarterly》1995,22(12):2246-2249
OBJECTIVE: Systemic sclerosis (SSc) is characterized by abnormal deposition of collagen in the skin and by visceral involvement. Muscle weakness is a relatively frequent complication of SSc, although severity varies. We studied muscle pathology in patients with SSc with progressive muscle involvement. METHODS: We performed histochemical and immunohistochemical investigations to detect neural cell adhesion molecule (NCAM). RESULTS: Five of the 6 cases of SSc expressed NCAM in atrophic angulated fibers (some fibers stained heavily with oxidative enzymes). CONCLUSION: Neurogenic involvement in SSc is more frequent than reported. 相似文献
84.
K Fujii K Takayasu T Ohkubo Y Muramatsu Y Mizuguchi S Yamasaki M Sakamoto T Abe 《Canadian Metallurgical Quarterly》1998,45(22):1085-1092
In an attempt to clarify the imaging characteristics of large early and early advanced hepatocellular carcinoma (HCC), we present two such cases which were greater than 5 cm in diameter. One case had four early HCCs and the other had early advanced HCC which was followed for five years and nine months. Multiphasic CT, CT arteriography (CTA), CT arterial portography (CTAP), and MR imaging were performed. Early HCC was shown as a low density mass by multiphasic contrast CT, CTAP and as a hyperintense mass on a T1-weighted image (WI) and isointense on T2WI. Early advanced HCC was demonstrated as a hypodense mass with hyperenhancing interior nodules on CTA, and isodense with hypodense internal foci on CTAP. One follow-up case showed a multi-step progression from early to early advanced HCC, and finally to overtly advanced HCC. Despite the unusually large size of these two tumors, the findings of multiphasic CT, CTA, CTAP, and MR imaging were consistent with those seen in common-sized (less than 2 cm) early and early advanced HCCs. Multi-step progression of hepatocarcinogenesis was observed in one case. 相似文献
85.
A cDNA clone encoding an endo-1,4-beta-glucanase from a rumen fungus, Neocallimastix frontalis MCH3, was isolated. The nucleotide sequence showed that the gene, celA, encoded a multidomain enzyme containing a family 5 catalytic domain and a reiterated sequence that is involved in the association of a multienzyme complex, the cellulosome. The enzyme expressed in Escherichia coli showed the highest activity against carboxymethylcellulose at 40 degrees C and pH 8.5. 相似文献
86.
M Murakoshi H Nishino Y Satomi J Takayasu T Hasegawa H Tokuda A Iwashima J Okuzumi H Okabe H Kitano 《Canadian Metallurgical Quarterly》1992,52(23):6583-6587
Although beta-carotene has been considered to be a key cancer preventive agent in green and yellow vegetables, other types of carotenoids, such as alpha-carotene, may also contribute to anticarcinogenic action, since these carotenoids usually coexist with beta-carotene and are detectable in human blood and tissues. In this study, we compared the inhibitory effect of natural alpha-carotene, obtained from palm oil, with that of beta-carotene on spontaneous liver carcinogenesis in C3H/He male mice. The mean number of hepatomas per mouse was significantly decreased by alpha-carotene supplementation (per os administration in drinking water at a concentration of 0.05%, ad libitum) as compared with that in the control group (P < 0.001, Student's t test). On the other hand, beta-carotene, at the same dose as alpha-carotene, did not show any such significant difference from the control group. Furthermore, we also compared the antitumor-promoting activity of alpha-carotene with that of beta-carotene against two-stage mouse lung carcinogenesis (initiator, 4-nitroquinoline 1-oxide; promoter, glycerol). alpha-Carotene, but not beta-carotene, reduced the number of lung tumors per mouse to about 30% of that in the control group (P < 0.001, Student's t test). The higher potency of the antitumor-promoting action of alpha-carotene compared to beta-carotene was confirmed in other experimental systems; e.g., alpha-carotene was also found to have a stronger effect than beta-carotene in suppressing the promoting activity of 12-O-tetradecanoylphorbol-13-acetate on skin carcinogenesis in 7,12-dimethylbenz[a]anthracene-initiated mice. These results suggest that not only beta-carotene, but also other types of carotenoids, such as alpha-carotene, may play an important role in cancer prevention. 相似文献
87.
Takayasu Ikegami 《Journal of the American Ceramic Society》1996,79(1):148-152
Model experiments were carried out with plastic polyhedra (cuboctahedra, in particular) contained in a beaker. The packing structures of these polyhedra were characterized in terms of three different types of contacts-point, line, and face contacts-along with the coordination numbers, n c . The present data indicate that the numerical distribution of n c shifted to larger values of n c with increasing distance from the beaker wall. On the other hand, the fractional values with respect to each specific type of contact, n p /( n p + n I + n f ), n I /( n p + n I + n f ), and n f /( n p + n I + n f ), changed little with location, except at the beaker wall. The small changes of these fractional values were explained with ignorance of the numerical distribution of contact angles and also of the contact areas in counting the three kinds of contacts. The measured percentages of point, line, and face contacts in the central region ranged from 17% to 20%, 60% to 65%, and 15% to 23%, respectively. The larger percentage of line contacts is attributable to the cooperation of two tendencies inducing opposite orders, namely (1) the stability of a contact between polyhedra free from the array of polyhedra around it, which gives n p < n I < n f and (2) the adaptability of a contact to an array of polyhedra around it, which gives n f < n I < n p . The number of contacts with small contact angles was substantial in the case of the point and line contacts. 相似文献
88.
89.
The effects of casting solvents, dissolution temperature of casting solution, and pH and temperature of gelation solution, etc. on the permeation characteristics of cellulose acetate membranes in the separation of polymers from their aqueous solutions were investigated, using aqueous solutions of poly(ethylene glycol) and poly(vinyl alcohol) as feed. The permeation characteristics were influenced significantly by the conditions of membrane preparation and of the permeation. It was found that a concentration polarization at the membrane surface occurred with poly(vinyl alcohol) molecules, but it was very small with poly(ethylene glycol). The above results were discussed in detail from points of view of structure of the resulting membranes and the interactions between the solvent, the solute in the feed and the cellulose acetate molecules. 相似文献
90.
Ceramides and cerebrosides were isolated from immature and mature soybeans, and structures of the constituents were investigated.
As component fatty acids, normal, 2-hydroxy and 2,3-dihydroxy acids were found in ceramides, whereas only normal and 2-hydroxy
acids were identified in cerebrosides. The principal fatty acid component was 2-hydroxylignoceric acid in ceramides, and 2-hydroxypalmitic
acid in cerebrosides. Sphingoids in ceramides consisted mainly of trihydroxy bases, with 4-hydroxy-trans-8-sphingenine being predominant. In contrast, cerebrosides contained mainly dihydroxy bases, the principal constituent beingtrans-4,trans-8-sphingadienine. The only sugar in cerebrosides was glucose. The constituents of the two sphingolipids were similar to each
other in immature and mature seeds. Possible metabolic relations of plant sphingolipids, based on composition, are discussed. 相似文献