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排序方式: 共有389条查询结果,搜索用时 15 毫秒
1.
T Noda M Arakawa T Takaya T Nagano K Kagawa H Miwa S Hirakawa 《Canadian Metallurgical Quarterly》1993,14(7):876-884
To evaluate right atrial (RA) contractile performance in patients with myocardial infarction, we validated a cineangiographic method of RA volume measurement, and investigated RA volume change in 'normal' individuals and patients with a previous myocardial infarction. Sixteen silicone rubber RA casts made from human cadavers were filmed in the postero-anterior and left lateral projections. The cast volumes calculated following Simpson's rule were in good agreement with those measured by water replacement (r = 0.992, P < 0.01). At cardiac catheterization, biplane RA cineangiography was performed in 19 'normal' individuals (N group), in 14 patients with a previous antero-septal infarction (AMI group) and in seven patients with a previous inferior infarction (IMI group). The RA volume-time curve was constructed at 20-40 ms intervals for one cardiac cycle. RA volume at the beginning of the atrial contraction (RAVd), which was defined as the 'preload' of the RA, tended to be larger in both the AMI and IMI groups compared with 'normal' individuals. The RA ejection volume was significantly larger in both the AMI (18.4 +/- 2.1 ml.m-2, P < 0.01) and IMI groups (19.4 +/- 2.8, P < 0.01) than in the N group (14.5 +/- 1.9), even for a comparable level of RAVd (range from 26 to 36 ml.m-2) (18.6 +/- 2.1, P < 0.01, 18.2 +/- 2.0, P < 0.01, 14.7 +/- 1.9, respectively). These results suggest that RA contraction increases in patients with myocardial infarction by increasing both the 'preload' and 'contractility' of the RA. 相似文献
2.
J Nishigami T Ohshima T Takayasu T Kondo Z Lin T Nagano 《Canadian Metallurgical Quarterly》1993,47(5):372-379
Using the TOXI-LAB drug detection system, emergency toxicological screening was performed in autopsy cases and emergency cares. In 280 autopsy cases (male 182 cases 65%, female 98 cases 35%), drug positive cases were 28 cases of male (15%) and 24 cases of female (24%). The age groups which showed higher rate of drug positive cases were 10s-40s in male (approximately 20%) and 20s in female (67%). In the 238 cases of emergency care (male 129 cases 54%, female 104 cases 44%, unknown 5 cases 2%), drugs were positive in 29 cases of male (22%) and 32 cases of female (30%). The age groups which showed relatively higher rate of drug positive cases were 40s in male (64%), 20s (71%) and 30s (89%) in female. Forty-four different kinds of drugs were detected in TOXI-LAB positive cases, in which the psychotropic drugs and the sedative-hypnotic drugs amounted to approximately 70%. Methamphetamine and amphetamine, which were the main abused drugs showing a socially important problem, were detected in total 15 cases. TOXI-LAB was based on thin-layer chromatography (TLC); however, from the extraction to development, coloration and detection have been accelerated (about 50 min) and simplified. In order to perform the forensic toxicological practice in Japan, it becomes more useful that TOXI-LAB is used in autopsy cases and emergency cares, if the drugs, which have caused poisoning cares in Japan, are added to TOXI-LAB. The present study describes the advantage and problem of TOXI-LAB drug detection system through demonstrating the practical cases of autopsy cases and emergency cares. 相似文献
3.
N Nakanishi C Nishioka A Yamada K Kimoto S Uzura Y Aoki H Yoneda K Nagano K Tatara 《Canadian Metallurgical Quarterly》1997,44(11):845-856
To estimate the risk factors for intellectual dysfunction and examine its prognosis in a community-residing (non-institutionalized) elderly population, a randomly selected sample of 1,473 elderly people aged 65 years and over living in S city, Osaka Prefecture, was studied in October 1992, and data were obtained from 1,383, a response rate of 93.9%. A cohort of 1,383 was followed for 42 months and follow-up was completed for 1,300 (94.0%). The main results were as follows: 1) The prevalence of intellectual dysfunction did not differ significantly between sexes, and there was an increasing prevalence of intellectual dysfunction with age in both sexes. The prevalence of severe intellectual dysfunction was found to increase highly at age 85 and over. 2) By univariate analysis, odds ratios for age older than 75 years, low Activities of Daily Living (ADL), urinary and fecal incontinence, and no participation in social activities were significantly higher than 1 in any level of mild, moderate, and severe intellectual dysfunction. In the multivariate analysis using logistic regression, age older than 75 years and urinary and fecal incontinence showed significant higher odds ratios than 1 for severe intellectual dysfunction, and low ADL and treatment for hypertension also showed significant higher odds ratios than 1 for moderate intellectual dysfunction. 3) From analysis using the Kaplan-Meier method, the cumulative survival rates decreased with a decline in intellectual functioning in both age groups of 65-74 and 75 years and older. 4) Application of the Cox proportional hazards model resulted in adjusted hazard ratio for severe intellectual dysfunction of 1.79 (95% confidence interval, 1.02-3.12), controlling for other factors such as sex, age, general health status, incontinence and social activities. 相似文献
4.
STATEMENT OF PROBLEM: Improved dental stone has been widely used for producing dies for the fabrication of restorations with the lost-wax technique. Improved dental stone is used for several reasons, but it is selected most often because of its reasonable cost, ease of use, and ability to produce consistent results. PURPOSE: This study evaluated the ability of an epoxy resin die material and a type IV dental stone to dimensionally reproduce a custom-fabricated metal die. MATERIAL AND METHODS: Dies were fabricated and measurements were made from three reference lines. Measurements were repeated three times for the master die and for the specimen dies. A mean measurement and percent relative change for each dimension was calculated. RESULTS: A significant difference in the relative change for die height was found between the groups studied (p < 0.003). CONCLUSIONS: This epoxy die system will provide a degree of dimensional accuracy comparable to gypsum when used with addition silicone impression material. 相似文献
5.
6.
Nobuhiko Yabu Kouhei Nagano Nozomu Izumi 《Journal of the Society for Information Display》2015,23(6):246-252
Using shorter wavelength for exposure light is one way to achieve high resolution while keeping sufficient depth of focus. We show exposure results for high resolution to confirm the effect of deep UV exposure light. With deep UV light, 1.2‐µm line and space pattern and 1.8‐µm contact hole pattern are resolved while keeping sufficient depth of focus. 相似文献
7.
Tsuchiya T. Nagano S. Paidi R.B. Kikuno T. 《Parallel and Distributed Systems, IEEE Transactions on》2001,12(1):81-95
A distributed system is said to be self-stabilizing if it converges to safe states regardless of its initial state. In this paper we present our results of using symbolic model checking to verify distributed algorithms against the self-stabilizing property. In general, the most difficult problem with model checking is state explosion; it is especially serious in verifying the self-stabilizing property, since it requires the examination of all possible initial states. So far applying model checking to self-stabilizing algorithms has not been successful due to the problem of state explosion. In order to overcome this difficulty, we propose to use symbolic model checking for this purpose. Symbolic model checking is a verification method which uses Ordered Binary Decision Diagrams (OBDDs) to compactly represent state spaces. Unlike other model checking techniques, this method has the advantage that most of its computations do not depend on the initial states. We show how to verify the correctness of algorithms by means of SMV, a well-known symbolic model checker. By applying the proposed approach to several algorithms in the literature, we demonstrate empirically that the state spaces of self-stabilizing algorithms can be represented by OBDDs very efficiently. Through these case studies, we also demonstrate the usefulness of the proposed approach in detecting errors 相似文献
8.
Yoshimitsu Sagara Toru Komatsu Tasuku Ueno Kenjiro Hanaoka Takashi Kato Tetsuo Nagano 《Advanced functional materials》2013,23(42):5277-5284
Switching of the luminescence properties of molecular materials in response to mechanical stimulation is of fundamental interest and also has a range of potential applications. Herein, a water‐soluble mechanochromic luminescent pyrene derivative having two hydrophilic dendrons is reported. This pyrene derivative is the first example of a mechanochromic luminescent organic compound that responds to relative humidity. Mechanical stimulation (grinding) of this pyrene derivative in the solid state results in a change of the photoluminescence from yellow to green. Subsequent exposure to water vapor induces recovery of the initial yellow photoluminescence. The color change is reversible through at least ten cycles. It is also demonstrated that this compound can be applied as a mechano‐sensing material in frictional wear testing for grease, owing to its immiscibility in non‐polar solvents and its non‐crystalline behavior. Transmission electron microscope and atomic force microscope observations of samples prepared from dilute aqueous solutions of the pyrene derivative on suitable substrates, together with dynamic light scattering measurements for the compound in aqueous solution, indicate that this amphiphilic dumbbell‐shaped molecule forms micelles in water. 相似文献
9.
Haiwei Dong Zhiwei Luo Akinori Nagano Nikolaos Mavridis 《Intelligent Service Robotics》2012,5(3):159-167
The key issue in this paper is estimating speed of a human. Compared with previous researches on walking speed estimation, we predict the walking intention before gait action. Our proposed hypothesis is that a composite force index is linearly correlated with the intended walking speed. We did two experiments to test the hypothesis. One gives a regression test indicating the intended walking speed has strong linear correlation with the proposed force index; the other tests the linearity by statistical analysis, guaranteeing the tolerance of individual difference. According to the regression and statistics analyses, we built a treadmill-style locomotion interface. Compared with the normal cases of treadmill control, the tested subject does not have to follow the speed of treadmill, but can actively change the speed of treadmill by his/her feet. The designed locomotion interface is applied in a virtual market system. Here the subject walks in a virtual market street with the desired speed. The stereo display based on virtual reality and the ambient sounds of the environment make the subject to have an immersed sense. The layout of shops in the virtual market system is in Japanese style, making the subjects experience much more realistic. 相似文献
10.
Kazuhiro Nagao Akira Koshino Akane Sugimura-Nagata Aya Nagano Masayuki Komura Akane Ueki Masahide Ebi Naotaka Ogasawara Toyonori Tsuzuki Kenji Kasai Satoru Takahashi Kunio Kasugai Shingo Inaguma 《International journal of molecular sciences》2022,23(6)
p53 immunohistochemistry is considered an accurate surrogate marker reflecting the underlying TP53 mutation status and has utility in tumor diagnostics. In the present study, 269 primary CRCs were immunohistochemically evaluated for p53 expression to assess its utility in diagnostic pathology and prognostication. p53 expression was wild-type in 59 cases (23%), overexpressed in 143 cases (55%), completely lost in 50 cases (19%), and cytoplasmic in 10 cases (4%). p53 immunoreactivity was associated with tumor size (p = 0.0056), mucus production (p = 0.0015), and mismatch repair (MMR) system status (p < 0.0001). Furthermore, among CRCs with wild-type p53 expression, a significantly higher number of cases had decreased CDX2 than those with p53 overexpression (p = 0.012) or complete p53 loss (p = 0.043). In contrast, among CRCs with p53 overexpression, there were significantly fewer ALCAM-positive cases than p53 wild-type cases (p = 0.0045). However, no significant association was detected between p53 immunoreactivity and the “stem-like” immunophenotype defined by CDX2 downregulation and ALCAM-positivity. Multivariate Cox hazards regression analysis identified tubular-forming histology (hazard ratio [HR] = 0.17, p < 0.0001), younger age (HR = 0.52, p = 0.021), and female sex (HR = 0.55, p = 0.046) as potential favorable factors. The analysis also revealed complete p53 loss (HR = 2.16, p = 0.0087), incomplete resection (HR = 2.65, p = 0.0068), and peritoneal metastasis (HR = 5.32, p < 0.0001) as potential independent risk factors for patients with CRC. The sub-cohort survival analyses classified according to chemotherapy after surgery revealed that CRC patients with wild-type p53 expression tended to have better survival than those with overexpression or complete loss after chemotherapy. Thus, immunohistochemistry for p53 could be used for the prognostication and chemotherapy target selection of patients with CRC. 相似文献