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131.
We have developed a method to use a half-size data page between two full-size data pages to increase the recording density in angular multiplexing holographic memory up to 1.5× as much as the conventional angular multiplexing sequence. In our recording sequence, the full- and half-size data pages are alternately multiplexed. This is because each plane wave from various points in a data page has different angular selectivity. A half-size data page has higher angular selectivity than a full-size data page. The required angular intervals were estimated by numerical simulation taking holographic medium tilt into account. Also, an angular multiplexing experiment using the half-data-page insertion method resulted in a low bit error rate of the order of 10(-3), which is sufficient for practical use.  相似文献   
132.
This paper reports on a new technique of measurements of microbubble position in three dimensions with high time-resolution. The technique is based on micro digital holographic particle tracking velocimetry. In this technique, an intensity profile is constructed from a holographic image of a microbubble where the profile results in showing two peaks. The distance between the two peaks appears to relate to the size of the microbubble's diameter. The three-dimensional position of the bubble can be detected by the center of the two peaks and the center point of the bubble image focused by a digital hologram. We also theoretically obtained the intensity profile of a microbubble by considering a refraction of light on a bubble surface to a ring-shaped aperture model. The theoretically obtained distance between the two peaks is found to be in good agreement with the values obtained experimentally.  相似文献   
133.
Kikuchi  K. Okoshi  T. 《Electronics letters》1985,21(22):1011-1012
Linewidths of 1.3 ?m InGaAsP lasers were measured by using delayed self-heterodyne set-ups with two different delay-line lengths, i.e. with two equivalent measurement times. It has been found that in high-power operation the linewidth increases as the measurement time becomes longer, and that this dependence is explained well by a calculation assuming that the 1/f noise in the FM noise spectrum is the predominant cause of the spectral broadening. The significance of this fact in coherent optical communications is discussed.  相似文献   
134.
This case study was designed to examine the self-defined health needs of families in one urban Western Australian community. We conducted 157 family interviews to examine the relationship between family sociodemographic variables and patterns of use of health services, which included services used within the previous 12 months, and what the family needed and wanted from these services. Questions covered perceptions of health, family health concerns and the role of the family health guardian. Quantitative analysis included frequencies, cross-tabulations, chi-squared tests and multiple regression analysis. Open-ended responses were categorised and analysed for common themes. Approximately 80 per cent of participants had used one or more health services during the previous 12 months and, despite 35.9 per cent of families having at least one family member with a long-standing illness, disability or infirmity, most (82.1 per cent) considered the family healthy. The correlational analysis revealed several associations. Predictably, younger persons reported higher health ratings and older persons had more health concerns. Larger families reported better perceived levels of health. Higher utilisation rates were recorded for families with children, who tended to use the general practitioner for general care and medication, whereas one-parent families used hospital and specialist care more often, and 98.7 per cent reported satisfaction with services. What they needed and wanted from their health service providers was 'full disclosure' and 'not being talked down to', and for specialists especially to be approachable and impart information simply and honestly.  相似文献   
135.
Social competence in subjects at risk for schizophrenia and affective disorder and in normal-comparison subjects was examined in childhood and adolescence. Based on interviews with the parents of the subjects and with the children and adolescents themselves, subjects at risk for schizophrenia had poorer overall social competence than subjects at risk for affective disorder and comparison subjects in early adolescence and adolescence but not in childhood. In analyses of specific aspects of social competence, the adolescents at risk for schizophrenia had significantly poorer peer relationships and decreased hobbies/interests than the adolescents at risk for affective disorder and the normal-comparison adolescents. With respect to school adjustment, however, the two groups of adolescent offspring of parents with psychiatric disorders had significantly poorer adjustment than the comparison adolescents but did not differ from each other on this measure. These results suggest that various aspects of poor social competence may precede the onset of schizophrenia and play an important role in its development.  相似文献   
136.
Helical computed tomography was performed with intravenous contrast material administration in ten patients with hepatic tumors (metastatic tumor, n = 6; hepatocellular carcinoma, n = 4). Maximum intensity projection (MIP) images of intrahepatic portal venous branches and hepatic veins, and shaded surface display (SSD) images of the hepatic tumors were reconstructed for each patient. The MIP image and SSD image were fitted to overlap on a single display to obtain three-dimensional (3-D) images showing both the hepatic vessels and hepatic tumors. Subsegmental localization of the tumors determined from the 3-D images proved to be correct in all of the six patients who received hepatic resection after examination. 3-D images seem to be useful for preoperative assessment of hepatic tumors.  相似文献   
137.
Ginsenoside Rh2 (Rh2), isolated from an ethanol extract of the processed root of Panax ginseng CA Meyer, inhibits the growth of B16 melanoma cells. This study was designed to evaluate the ability of Rh2 to inhibit growth of human ovarian cancer cells (HRA) in vitro and in nude mouse. Rh2 inhibited proliferations of various established human ovarian cancer cell lines in a dose-dependent manner between 10 and 60 microM in vitro and induced apoptosis at around the IC50 dose. When HRA cells were inoculated s.c. into the right flank of nude mice, all mice formed a palpable tumor within 14 days. Although i.p. administration of Rh2 alone hardly inhibited the tumor growth, when Rh2 was combined with cis-diamminedichloroplatinum(II) (CDDP) the tumor growth was significantly inhibited, compared to treatment with CDDP alone. When mice were treated p.o. with Rh2 daily (but not weekly), the tumor growth was significantly (P<0.01) inhibited, compared to CDDP treatment alone. When Rh2 was combined with CDDP, the degree of tumor growth retardation was not potentiated. The survival time was significantly (P<0.05) longer than that of medium alone-treated controls or the group treated with CDDP alone. Then, we examined whether p.o. administration of Rh2 has a dose-dependent inhibitory effect on the tumor growth. I.p. and weekly administration of CDDP had more potent antitumor activity in the order of 1 mg/kg, 2 mg/kg and 4 mg/kg, whereas p.o. and daily administration of Rh, (0.4 to 1.6 mg/kg) not only had antitumor activity comparable to that of 4 mg/kg CDDP, but also resulted in a significant increase of the survival. Doses of Rh2 used in this study did not result in any adverse side-effects as confirmed by monitoring hematocrit values and body weight, unlike 4 mg/kg CDDP, which had severe side-effects. It is noteworthy that p.o. but not i.p. treatment with Rh2 resulted in induction of apoptotic cells in the tumor in addition to augmentation of the natural killer activity in spleen cells from tumor-hearing nude mice. Thus, particularly in view of the toxicity of CDDP, Rh2 alone would seem to warrant further evaluation for treatment of recurrent or refractory ovarian tumor.  相似文献   
138.
The effects of chronic maternal administration of ethanol on nitric oxide synthase (NOS) activity and the numbers of NOS containing neurons, and CA1 and CA3 pyramidal neurons in the hippocampus of the near term fetal guinea pig at gestational day (GD) 62 were investigated. Pregnant guinea pigs received oral administration of 4 g ethanol/kg maternal body weight (n = 5), isocaloric sucrose/pair feeding (n = 5) or water (n = 5), or no treatment (NT; n = 5) from GD 2 to GD 61. NOS activity in the 25,000 x g supernatant of hippocampal homogenate was determined using a radiometric assay. The numbers of NOS containing neurons, and CA1 and CA3 pyramidal neurons were determined using NADPH diaphorase histochemistry and cresyl violet staining, respectively. The chronic ethanol regimen produced a maternal blood ethanol concentration of 193 +/- 13 mg/dl at 1 h after the second divided dose on GD 57. Chronic ethanol exposure produced fetal body, brain, and hippocampal growth restriction and decreased fetal hippocampal NOS activity compared with the isocaloric sucrose/pair feeding, water, and NT experimental groups, but did not affect the number of NOS containing and CA1 or CA3 pyramidal neurons. These data demonstrate that, in the near term fetus, chronic maternal administration of ethanol suppresses hippocampal NOS activity and consequent formation of NO, without loss of NOS containing neurons and prior to loss of CA1 pyramidal neurons that occurs in the adult.  相似文献   
139.
Kikuchi  K. Katoh  K. 《Electronics letters》2002,38(6):283-285
An optical heterodyne receiver that can select any channel out of 2.5 Gbit/s frequency division multiplexed (FDM) signals with spacing as narrow as 5 GHz has been developed. Sharp filtering characteristics of the heterodyne receiver at the intermediate frequency stage enable FDM signals with such narrow channel spacing to be demultiplexed  相似文献   
140.
STUDY DESIGN: The authors investigated the positions of dorsal root ganglia and the relation of the location to symptoms and to the effects of nerve root infiltration in the cervical spine anatomically and clinically. OBJECTIVES: To clarify normal variation of positions of dorsal root ganglia and the relation of the location of dorsal root ganglia to symptoms and to the effects of nerve root infiltration. SUMMARY OF BACKGROUND DATA: The dorsal root ganglia of the spinal nerve has attracted much attention as an important structure in the mechanisms of radicular symptoms in the lumbar spine. Although the position of the dorsal root ganglia in the lumbar spine has been classified recently, there are few reports regarding the dorsal root ganglia in the cervical spine. METHODS: The positions of dorsal root ganglia were divided into two types: proximally situated and distally situated. The positions of dorsal root ganglia in the anatomic and clinical cases were compared. The relation of the positions of dorsal root ganglia to symptoms and to the clinical effects of nerve root infiltration were analyzed. RESULTS: There was no statistically significant difference in positions of dorsal root ganglia in C6 nerve roots between anatomic and clinical cases. In addition, there was no relation between symptoms and the positions of dorsal root ganglia in clinical cases. However, there was a significant difference in positions of dorsal root ganglia in C7 nerve roots between anatomic and clinical cases. Nerve root infiltration was significantly more effective in the distally situated type of dorsal root ganglia. CONCLUSIONS: This study defined the normal variation of the positions of dorsal root ganglia. The results strongly suggest that some attention should be paid to the position of dorsal root ganglia in the diagnosis and treatment of cervical radiculopathy.  相似文献   
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