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91.
Tamada  Tsutomu  Ueda  Yu  Kido  Ayumu  Yoneyama  Masami  Takeuchi  Mitsuru  Sanai  Hiroyasu  Ono  Kentaro  Yamamoto  Akira  Sone  Teruki 《Magma (New York, N.Y.)》2022,35(4):549-556
Magnetic Resonance Materials in Physics, Biology and Medicine - Image quality (IQ) of diffusion-weighted imaging (DWI) with single-shot echo-planar imaging (ssEPI) suffers from low signal-to-noise...  相似文献   
92.
93.
To clarify how and why blood pressure differs between occupations, the proportions of hypertensives, and the measures of blood pressure, body mass index (BMI) and alcohol consumption among the individuals not taking antihypertensive drugs were compared between the eight occupational categories using the data from a health check-up for 589 middle-aged Japanese males, mostly randomly selected from five areas in Japan. After adjusting for age, the relationships of occupation to the proportion of hypertensives and the mean systolic and diastolic blood pressure substantially differed among the five areas. However, after further adjustment for residence, these blood pressure levels (the proportion of hypertensives, and the mean systolic and diastolic blood pressure) were found to be higher for the "Personnel in transport and communications", the "Clerical personnel", the "Managerial and civil personnel" and the "Professional and technical personnel", whereas these values were consistently lowest in the "Service personnel". Age and residence-adjusted mean BMI was also higher for the four occupational categories with the increased blood pressure levels. According to a weighted multiple regression analysis across the eight occupations, the age and residence-adjusted mean BMI was a significant predictor of the age and residence-adjusted mean systolic and diastolic blood pressure (p = 0.068 and 0.018, respectively). These results suggest that the occupation-related changes in BMI may largely contribute to the occupation-related changes in blood pressure.  相似文献   
94.
The thermal conductivity of high density La2–xMxCuO4 (M=Ba, Sr) sintered materials was measured between 15K and 150K for the various concentrations of Ba and the phonon thermal conductivity was analyzed comparing with that of Nd2–xCexCuO4. The pretty large value for pure La2CuO4 was drastically diminished by substituting La by a small amount of Ba atoms especially at low temperatures. It was found that a new type of the phonon scattering center such as a two-level tunneling must be taken account of in order to explain the observed reduction.  相似文献   
95.
The long-term effects of the initial methylmercury exposure in the Minamata area were examined, with focus on brain weight. Comparisons were made between the brain weights of methylmercury-contaminated persons in the Minamata area (cases) and those of Japanese who suffered sudden or accidental death without brain disease (controls). Since over thirty years have passed since the outbreak of Minamata disease, subjects aged 30 or over at death were included in the analysis. The total number of cases was 417 (273 males, 144 females) and that of controls was 2,934 (2,174 males, 760 females). The data suggest that the brain weights from Minamata cases were reduced by 80 to 200g as compared to the controls. These results may indicate that methylmercury exposure led to a decrease of nerve cells (single cell necrosis), so-called "thinning out", in the brain cortex.  相似文献   
96.
Azithromycin (AZM), a new macrolide antibiotic, in fine granules and in capsules was studied for pharmacokinetic and clinical evaluation in the pediatric patients. Antibacterial activity of AZM against 43 clinical isolates: AZM exhibited slightly lower activity against Gram-positive bacteria and 2-8-fold higher activity against Gram-negative bacteria than erythromycin or clarithromycin. Plasma or urine samples were collected from eight patients receiving the drug in fine granular form, and two patients receiving it in capsules for the determination of drug levels. The elimination half-lives of AZM after administration at dose of 10 mg/kg/day for 3 days were 50.0 and 51.2 hours for fine granules, and 41.5 hours for capsules. AUC0-infinity was 11.7 and 24.3 micrograms.hr/ml for fine granules, and 8.3 micrograms.hr/ml for capsules. The cumulative excretion rates up to 120 hours after the start of treatment were 8.24 and 13.84% for fine granules, and 3.83% for capsules. AZM was administered to 123 patients once daily at 3.7-20.0 mg/kg body weight over 3 to 5 days with reference to the standard dose of 10 mg/kg. The drug was used to treat patients with pharyngitis, tonsillitis, scarlet fever, pneumonia, mycoplasmal pneumonia, chlamydial pneumonia, otitis media, pertussis, intestinal infection, and SSTI. The effectiveness of AZM was evaluated in 109 cases. The drug was rated "excellent" in 65.1% of the patients and "good" in 29.4%, resulting in an efficacy rate of 94.5%. Furthermore, AZM eradicated 43 of 46 (93.5%) bacteria that had been identified before the treatment. Three patients complained of side effects of urticaria (1 case) and diarrhea (2 cases). Abnormal laboratory changes were reported as follows: decreased leukocyte (3 cases), increased eosinophil (5), increased platelet (2), increased eosinophil and platelet, elevated GPT (1), and elevated GOT and GPT (1). The abnormalities, however, were mild enough to raise no clinically significant problems. In conclusion, AZM in once daily regimen was effective and safe in treatment of pediatric infections.  相似文献   
97.
For sustainable manufacturing, manufacturers should construct and design inverse manufacturing systems consisting of assembly and disassembly systems. The sorting process in the disassembly system is the first process of the whole inverse manufacturing system. Therefore, it can become a bottleneck and decrease the productivity of the whole inverse manufacturing systems.This study focuses on a disassembly system with reverse blocking in a sorting process [Yamada, T., & Matsui, M. (2003). Disassembly production systems and its design issues. Reprints of Japan Industrial Management Association, Spring meeting, Chofu, Japan, May, 144–145 (in Japanese)]. It generalizes the queuing model and discusses the performance of the disassembly system by mathematical and numerical analysis. First, the sorting process with reverse blocking is generally modeled as a queuing system. Next, the stationary state equations of the system are formulated, and the objective function is set as the throughput. Finally, the system performance is discussed by mathematical and numerical analysis in cases of a different number of stations and buffers, and also an example of the system design is shown and discussed in view of the busy rate, blocking probability and throughput.  相似文献   
98.
We propose a computationally efficient method for cross-validation of the Support Vector Regression (SVR) by generalizing the decremental algorithm of SVR. Incremental and decremental algorithm of Support Vector Machines (SVM) 2, 8, 9) efficiently update the trained SVM model when a single data point is added to or removed from the training set. The computational cost of leave-one-out cross-validation can be reduced using the decremental algorithm. However, when we perform leave-m-out cross-validation (m > 1), we have to repeatedly apply the decremental algorithm for each data point. In this paper, we extend the decremental algorithm of SVR8, 9) in such a way that several data points can be removed more efficiently. Experimental results indicate that the proposed approach can reduce the computational cost. In particular, we observed that the number of breakpoints, which is the main computational cost of the involved path-following, were reduced from \({\mathcal O}(m)\) to \({\mathcal O}(\sqrt{m})\).  相似文献   
99.
An accurate finite element method is developed for atomic calculations based on density functional theory (DFT) within local density approximation (LDA) and Hartree–Fock (HF) method. The radial wave functions are expanded by cubic Hermite spline functions on a uniform mesh for , and all the associated integrals are analytically evaluated in conjunction with fitting procedures of the Hartree and the exchange–correlation potentials to the same cubic Hermite spline functions using a set of recurrence formulas. The total energy of atoms systematically converges from above, and the error algebraically decays as the mesh spacing decreases. When the mesh spacing d is taken to be , the total energy for an atom of atomic number Z can be calculated within error of 10−7 hartree for both the LDA and HF methods. The equal applicability of the method to DFT and the HF method with a similar degree of high accuracy enables the method to be a reliable platform for development of new functionals in DFT such as hybrid functionals.  相似文献   
100.
We investigated whether beta-amyloid (Abeta)-like immunoreactivity was seen in the brains of newborn piglets. The immunoreactivity for Abeta(1-42) and Abeta(1-40) proteins, but not Abeta precursor protein, was present in CD68-positive perivascular cells of the hippocampus and in parts of the meninges. It was colocalized with immunoreactivity for receptor for advanced glycation end product and tumor necrosis factor-alpha. The protein with a molecular mass of 27 kDa, which was recognized by the Abeta antibodies, was identified as triosephosphate isomerase (TPI) with sequence homology to Abeta peptides by N-terminal amino acid sequencing, mass fingerprint analysis using matrix-associated laser desorption/ionization mass spectrometry, and Western blotting. Western blotting assay also revealed that detectable expression of Abeta proteins were not seen in the piglet brains. These findings indicate that TPI with sequence homology to Abeta peptides accumulates in perivascular cells of the microglia/macrophage lineage located around arterial vessels of the newborn piglet hippocampus.  相似文献   
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