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排序方式: 共有767条查询结果,搜索用时 15 毫秒
761.
762.
Omori Y Sakikubo T Nakane M Fuchu H Miake K Kodama Y Sugiyama M Nishikawa Y 《Journal of food protection》2010,73(10):1803-1808
To manufacture raw ham in an efficient manner, we recently developed a new system in which presliced pork loin was used, and the processing time was reduced to 5% of the conventional method. This study aimed to examine whether this raw ham could be as safe as ham produced by the conventional method. Pork loin spiked with enterohemorrhagic Escherichia coli serotype O157:H7, Listeria monocytogenes serotype 1/2c, Salmonella enterica serovar Enteritidis, and Staphylococcus aureus were processed using either the new or conventional method. The fate of the foodborne pathogens and behavior of hygiene indicator bacteria were examined. Whereas nitrite had disappeared during the conventional packaging process, the reduced processing time in the new system allowed for the ham to be vacuum packed with retention of the nitrite (6.9±1.2 ppm, P<0.01). This accounts for the prominent decrease in L. monocytogenes (2.3 log reduction in 35 days) and S. aureus (3.3 log reduction in 13 days) counts during storage. E. coli O157 and Salmonella Enteritidis were likely resistant to the nitrite in the ham. However, they were unable to multiply in the ham and decreased gradually as in the conventionally produced ham. The bacteriostatic nature of the raw ham was also indicated by the gradual decrease in coliforms (1.3 log reduction in 13 days) in nonspiked ham. In conclusion, the raw ham produced using presliced pork loin is practically as safe as conventionally produced raw ham. It is worth validating these results in a small-scale production setting. 相似文献
763.
Utilization of second-, third-, and fourth-order diffraction is discussed for providing a single reflection grating lens that yields the same wave-front conversions for wavelengths of 420, 280, and 210 nm, which are used to sense NO(x) and SO(2) gas densities. A blazed grating lens was fabricated by a planar process and characterized by use of UV lamps. The same wave-front conversion was observed at the three UV wavelengths. Efficiencies were measured to be 80%, 70%, and 30% for second-, third-, and fourth-order diffractions, respectively, at wavelengths of 420, 280, and 210 nm, respectively. 相似文献
764.
Monolayer MoS2 Films Supported by 3D Nanoporous Metals for High‐Efficiency Electrocatalytic Hydrogen Production 下载免费PDF全文
765.
We proposed a new quasi-matrix ferroelectric memory for use in future silicon-storage media. The memory unit consists of multiple ferroelectric capacitors and one access transistor. Each capacitor stores 1 bit of data, and the access transistor is shared by several capacitors. Compared with conventional crosspoint matrix type FeRAMs, which cause a signal degradation by read/write disturbance, this memory limits the disturbing frequency to an acceptable level by accessing the memory unit as a whole. Crosstalk noise was also minimized by applying a unique access scheme. This memory has a scalability by adopting built-in sense circuits, and enables an extremely high packing density with three-dimensional multistacking structures of memory cells. 相似文献
766.
B Nakata YS Chung S Nishimura T Nishihara Y Sakurai T Sawada T Okamura J Kawabe H Ochi M Sowa 《Canadian Metallurgical Quarterly》1997,79(4):695-699
BACKGROUND: Fluorodeoxyglucose (FDG) detected by positron emission tomography (PET) can be used to measure the glycolytic activity of tumor cells. Though the prognosis of patients with pancreatic adenocarcinoma is usually poor, a subset of patients with good prognoses may be discovered by determining the degree of FDG integration into tumors. METHODS: Fourteen patients with histologically proven pancreatic adenocarcinoma underwent 18F-FDG PET. The standardized uptake value (SUV) of 18F-FDG was calculated, and the patients were divided into high (> or = 3.0) and low (< 3.0) SUV groups. RESULTS: The two groups were not significantly different in terms of age, tumor location and size, staging, and treatment. However, analysis by the Kaplan-Meier method revealed that the groups had different prognoses (log rank test, P < 0.05). The mean survival of patients with high SUV was 5 months, whereas that of patients with low SUV was 14 months. There were not strong correlations between the SUVs and tumor size (0.56), serum carbohydrate antigen 19-9 (0.39), or carcinoembryonic antigen (0.52). CONCLUSIONS: SUV calculated with 18F-FDG can be utilized as a prognostic factor for patients with pancreatic adenocarcinoma. 相似文献
767.
Hiroki Iwamoto Kenji Nishihara Takahiro Yagi Cheol-Ho Pyeon 《Journal of Nuclear Science and Technology》2017,54(4):432-443
To investigate the applicability of the pulsed neutron source method using a pulsed spallation neutron source for an on-line subcriticality monitoring system of an accelerator-driven system, a subcritical experiment is conducted using the Kyoto University Critical Assembly in combination with the fixed-field alternating gradient accelerator. Reactivity values obtained from different traditional techniques, the area-ratio method and the α-fitting method, are discussed with respect to the applicability to on-line subcriticality monitoring. The results show that the area-ratio method robustly and accurately monitors subcriticality in shallow subcritical states with negative reactivity of up to a few dollars; however, this method faces problems with temporal fluctuations, spatial dispersion, and sensitivity to the proton-beam current with increasing depth of subcriticality. On the other hand, it is shown that the α-fitting method alleviates such problems in deep subcritical states. Moreover, a proposed fitting technique using the maximum-likelihood estimation method based on the Poisson distribution is robust enough to be applicable to on-line subcriticality monitoring for negative reactivity levels of up to roughly nine dollars. 相似文献