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排序方式: 共有777条查询结果,搜索用时 15 毫秒
81.
K Yamamoto S Kusachi Y Ninomiya M Murakami M Doi K Takeda T Shinji T Higashi N Koide T Tsuji 《Canadian Metallurgical Quarterly》1998,30(9):1749-1756
Biglycan, a small dermatan sulphate proteoglycan, has been postulated to interact with other components of the extracellular matrix (ECM), specifically collagens. We hypothesized that biglycan messenger ribonucleic acid (mRNA) is increased in the myocardial infarct zone. Biglycan mRNA expression after acute myocardial infarction (AMI) in rats was determined with the use of Northern blotting and in situ hybridization, and its expression pattern was compared to that of type I collagen mRNA [alpha1(I) collagen]. The left coronary artery was ligated in male Sprague-Dawley rats, and the hearts were excised on days 2 and 7. The Northern blot analysis demonstrated that expression of biglycan mRNA in the infarct on days 2 and 7 were 4.0- and 6.8-fold higher, respectively, compared to the sham-operated hearts. The in situ hybridization revealed intense signals for both biglycan and alpha1(I) collagen mRNA on day 2 in the spindle-shaped mesenchymal cells located between the surviving myocytes in the infarct peripheral zone. On day 7, biglycan mRNA signals were observed in the interior of the infarct around the infarct granulation tissue, a distribution that was essentially the same as that of alpha1(I) collagen. These results demonstrated that the increases in the infarct biglycan mRNA expression produced by mesenchymal cells (presumably myofibroblasts and fibroblasts) was closely co-localized with that of type I collagen mRNA, indicating that biglycan contributes to the infarct healing processes. 相似文献
82.
Anopheles tessellatus mosquitoes ingested Plasmodium vivax gametocytes in human erythrocytes suspended in rabbit sera with and without anti-mosquito midgut antibodies. When the mosquito bloodmeal contained anti-midgut antibodies, fewer oocysts of P.vivax developed on the mosquito midgut and the proportion of mosquitoes becoming infected was significantly reduced. Complement inactivated serum also reduced the infection rate and load. A second bloodmeal containing anti-midgut antibodies, given 48 or 72 h later, did not enhance the transmission-blocking effect. IgG purified from anti-midgut sera was shown to mediate the transmission-blocking effect. 相似文献
83.
Ajantha Herath Yasuaki Hyodo Y. Kunieda Takashi IkedaSusantha Herath 《Information Sciences》1996,90(1-4):303-319
This paper presents the design and implementation techniques employed in a Japanese-to-Sinhalese machine translation system. The main result of this work is the successful application of Bunsetsu in generating meaningful translations for a flexible-grammar language. The system has been developed considering the similarities between Japanese Bunsetsu and Sinhalese units. Such efforts are being focused on determining the minimum reasonable grammatical knowledge necessary for machine translation. The principal characteristics of the system, the translation process, problems encountered during the development stages, present status, and future plans will be discussed. 相似文献
84.
H Yoshii M Sato S Yamamoto M Motegi S Okusawa M Kitano A Nagashima M Doi K Takuma K Kato N Aikawa 《Canadian Metallurgical Quarterly》1998,45(1):45-50; discussion 50-1
BACKGROUND: In the assessment of blunt abdominal trauma, the reliability of ultrasonography (US) in identifying individual organ injuries remains uncertain, in spite of its usefulness in detecting hemoperitoneum. This study was designed to evaluate the overall diagnostic value of US, including identification of individual organ injuries. METHODS: The accuracy of US in the detection of intra-abdominal injuries and the identification of individual organ injuries was evaluated in 1,239 patients seen during a 15-year period. Accuracy was based on detection of intraperitoneal fluid, free air, or irregular parenchymal lesions. RESULTS: For the detection of injuries, US was 94.6% sensitive, 95.1% specific, and 94.9% accurate. Individual organ injuries were identified with sensitivities of 92.4, 90.0, 92.2, 71.4, and 34.7% for the liver, spleen, kidneys, pancreas, and intestine, respectively. CONCLUSION: US is reliable for the detection of injuries and the identification of solid-organ injuries despite its poor sensitivity for intestinal injuries. 相似文献
85.
86.
S Morimoto A Hirano T Ohkawa J Doi A Suzuki K Hagino S Kitamura Y Sawada T Morita Y Miyazaki 《Canadian Metallurgical Quarterly》1995,41(4):245-251
One hundred and sixty one patients with upper urinary stones were examined for antimicrobial prophylaxis following extracorporeal shock wave lithotripsy (ESWL). They were divided into two groups, the low-risk group (n = 133) and high-risk group (n = 28), according to the risk factors of urinary tract infection. The patients in the low-risk group were further randomized into two groups which were orally given ofloxacin for 7 days after ESWL (Group A, n = 66), no antimicrobial (Group B, n = 67). The patients in the high-risk group were randomly subdivided into three groups which were given flomoxef intravenously for 2 or 3 days and ofloxacin for 4 or 5 days thereafter (Group C, n = 10), flomoxef only for 2 or 3 days and no drugs later (Group D, n = 10), ofloxacin for 7 days (Group E, n = 8). In all of the patients in the low-risk group, during the 7 days after ESWL, fever elevation was observed in only 1.5% of patients, and bacteriuria in 10.0% on the 7th day. There was no difference in frequency of fever elevation and bacteriuria following ESWL between Group A and Group B. These findings indicate that prophylactic antimicrobial after ESWL treatment is not necessary for low risk patients with urinary tract infections. In the high-risk group, the over-all rates of fever elevation and bacteriuria were 21.4% and 24.0% respectively. The difference of effectiveness among the prophylactic regimens of the three groups (Group C, D, E) was not shown.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
87.
Lakshmi Sharma Yoshino Ogino Toshiji Kanaya Tadahisa Iwata Yoshiharu Doi 《Journal of Materials Science》2006,41(17):5687-5695
In MMWT/UHMWT PHB blends (99.5/0.5), (99/1), (98/2) and (97/3) we demonstrate that by applying our new shear technique, “semi continuous shear flow”, copious fibre formation is guaranteed, irrespective of the ultra high molecular weight composition. The shishes formed via this technique are extremely stable being able to maintain their stability for at least 5–10 min. When this technique was applied to MMWT/UHMWT PHB blends of compositions (95/5), (90/10) and (85/15) disorientated fibres were observed in the flow direction. On increasing the UHMWT component, distinct unordered and intertwining of fibres resulted and with severe shearing orientation occurred, however shish formation was limited. We propose the optimum conditions for shish formation and the critical molecular weight necessary for entanglement. 相似文献
88.
Morphological examinations were carried out on hepatocyte nuclei of streptozotocin (SZ)-induced diabetic mice. The area of hepatocyte nuclei in diabetic mice was about two times larger than that in control mice, and the incidence of hepatocytes with intranuclear inclusions was 3.4 +/- 0.2% in diabetic mice and 0% in control mice, respectively. Although the incidence of binuclear hepatocytes was not significantly different between diabetic (14.5 +/- 4.6%) and control mice (16.4 +/- 4.4%), the morphology of the nuclei of binuclear hepatocytes was apparently different between diabetic and control mice. Namely, the nuclei of binuclear hepatocytes of control mice were round and identical in ultrastructural appearance, and they did not differ from those of mononuclear diploid hepatocytes. On the other hand, the nuclei of binuclear hepatocytes of diabetic mice were not identical in distribution pattern of chromatin granules, and they frequently varied in size and showed irregular contours. 相似文献
89.
Mine detection using scattering parameters 总被引:1,自引:0,他引:1
The detection and disposal of antipersonnel land mines is one of the most difficult and intractable problems faced in ground conflict. This paper presents detection methods which use a separated-aperture microwave sensor and an artificial neural network pattern classifier. Several data-specific preprocessing methods are developed to enhance neural network learning. In addition, a generalized Karhunen-Loeve transform and the eigenspace separation transform are used to perform data reduction and reduce network complexity. Highly favorable results have been obtained using the above methods in conjunction with a feedforward neural network. 相似文献
90.
In a primary cell culture system of fetal rat brain, the calmodulin-dependent protein-kinase IV (CaMKIV) could be induced by the thyroid hormone T3 in a time- and concentration-dependent manner, provided the tissue was excised not later than day 15 of gestation (E15) (Krebs et al., J. Biol. Chem. 271, 11055, 1996). We report here that in the fetal thymus CaMKIV could not be detected earlier than day 16 of gestation and that the expression of this enzyme was fully upregulated at day 18. In mouse fetal thymus organ culture (FTOC) of day 14 embryonic thymus, CaMKIV could not be detected, even after several days of culture if a minimal culture medium lacking fetal calf serum was used. However, after addition of fetal calf serum to the culture medium the expression of CaMKIV could be specifically induced. Furthermore, it could also be shown that during T-cell development in the adult murine thymus the expression of CaMKIV was tightly regulated. Taken together, these results demonstrate that the expression of CaMKIV, an enzyme involved in the regulation of Ca(2+)-dependent gene expression, is itself under stringent regulatory control during tissue development. 相似文献