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31.
We have proposed an illumination-collection-type scanning near-field Raman spectroscopy (SNRS) with a completely gold metal-inside-coated (MIC) pyramidal probe without an optical aperture in order to detect the Raman spectra of fine Si devices for local stress measurements. The gold MIC pyramidal probe has been studied to act as a plasmon resonance near-field optical probe with high power using a finite differential time domain (FDTD) simulation and the prototyped SNRS. In the simulation, the propagated optical power can be made available for SNRS. In the experiments, it is clear that the prototyped SNRS enhanced the Si Raman peak signal by plasmon resonance and could measure the Si Raman peak shift by line scanning the Si gate region and the Si active layer. Furthermore, compressive and tensile stresses localized around the Si gate were demonstrated by the Si Raman peak shift with a resolution of about 10 nm. It is clarified that the proposed SNRS has the possibility of detecting the Raman spectra of a local area. 相似文献
32.
33.
K Kubo Y Yamazaki T Masubuchi A Takamizawa H Yamamoto T Koizumi K Fujimoto Y Matsuzawa T Honda M Hasegawa S Sone 《Canadian Metallurgical Quarterly》1998,158(3):979-984
To clarify the structure and function of the airways in Mycobacterium avium-intracellulare (MAI) infection, we performed pulmonary function tests and high-resolution computed tomography (HRCT) of the thorax in female patients 61 +/- 9 yr of age (n = 12) with pulmonary MAI infection without predisposing lung disease and compared their data with those of normal female volunteers 54 +/- 8 yr of age (n = 9). We calculated the E/I ratio, i.e., the average ratio of HRCT number at full expiration to that at full inspiration, as an index for the evaluation of air trapping distal to the small airways. Patients showed significant increases in residual volume and slope of phase III (DeltaN2) of the single-breath nitrogen test, and significant decreases in flow at 50 and 25% of FVC, suggesting hyperinflation and obstruction of the small airways. HRCT of patients revealed the small nodules and ectasis of bronchioles and small bronchi located mainly in segments (S) S2, S3, S4, and S5. The E/I ratio was significantly elevated in patients, and especially higher in the upper lung field than in the lower lung field, suggesting air trapping distal to the small airways. The difference of E/I ratio between the upper and lower field is probably related to the segmental distribution of CT abnormalities. These findings suggest that MAI infection can lead to air trapping distal to the small airways. 相似文献
34.
K. S. Ramaiah D. Huang M. A. Reshchikov F. Yun H. Morkoç J. Jasinski Z. Liliental-Weber C. Sone S. S. Park K. Y. Lee 《Journal of Materials Science: Materials in Electronics》2003,14(4):233-245
Structural and optical studies have been performed on GaN, InGaN layers, In0.08Ga0.92N/GaN heterostructures, In0.08Ga0.92N/In0.02Ga0.98N single and multiquantum wells grown by metal organic chemical vapor deposition (MOCVD) and GaN by molecular beam epitaxy (MBE) on GaN templates by using transmission electron microscopy (TEM), X-ray diffraction (XRD), and photoluminescence (PL). The layers are found to be high quality with low defect density, on the order of 106 cm?2, which are mainly related to the threading dislocations originating/propagating from the hydride vapor phase epitaxy (HVPE) GaN template. The interface between the layers and substrate could not be detected by TEM and was therefore deemed to be of high quality. Convergent beam electron diffraction studies revealed that the polarity of the films is Ga-polarity, which is the same as that of the substrate. A dual structure with different compositions and having thicknesses of 10 and 25 nm was observed in InGaN layers grown on GaN in one of the heterostructure samples. The full width at half maximum (FWHM) of the XRD rocking curves of (0 0 0 2) for heterostructures and quantum wells were found to be in the range of 15–28 arcmin for a slit width of 2 mm. PL studies on GaN layers grown by MBE and MOCVD on GaN templates are reasonably similar. The PL spectra from all the MBE and MOCVD epilayers and the substrate contain a plethora of sharp peaks related to excitonic transitions. With the presence of donor-bound exciton peaks and their associated two-electron satellites, the binding energies of two distinct shallow donors (28.8 and 32.6 meV), which are attributed to Si and O, respectively, were determined. PL measurements revealed that the FWHM of the main donor bound exciton peak increased from 0.6 to 2.9 meV but no change in peak position (3.472 eV) was observed in GaN when doping with Si (5×1017 cm?3). However, the intensities of the yellow band and the shallow donor–acceptor pair band increased 10 times as compared to that in the undoped GaN samples. In the case of InGaN/GaN heterostructures, a similar trend was observed when compared to the doped samples. In the multiquantum well In0.08Ga0.92N/In0.02Ga0.98N heterostructures, the activation energy of the exciton emission, found to be 18 meV, was the lowest in the samples studied. The peak at 3.02 eV related to the InGaN was strongly pronounced in the In0.08Ga0.92N/In0.02Ga0.98N multiquantum well structure. In the In0.08Ga0.92N/In0.02Ga0.98N quantum well structures, the change in peak position with variation of temperature from 15 to 300 K in PL spectra is “S”-shaped. The cause for the “S” shape, i.e., a red–blue–red shift, is discussed. 相似文献
35.
OBJECTIVE: To evaluate the incidence of non-specific granulomatous prostatitis (GP) in our series of prostate biopsies and to verify whether there were differences in the features of DRE, PSA and ultrasound findings in patients with GP and patients with prostate cancer that could be used as clinical indications in GP diagnosis. MATERIAL AND METHODS: Between 1994 and 1996, 835 patients with prostatic syndromes underwent echoguided transrectal biopsy. Neoplasia was diagnosed in 323 (39%) patients, non-specific GP in 11 (1.5%), whereas no malignancy signs were found in the remaining 501 (59.7%). A retrospective comparison of DRE features, PSA levels and the existence of echographic nodes was conducted between cancer patients and GP patients. RESULTS: 55% GP patients had suspicious DRE; in 64% at least one node with different echogeneicity was identified in the transrectal ultrasound, and the mean PSA value was 17.3 ng/ml. When they were compared to the group of patients with prostate cancer, no significant differences were found. CONCLUSION: In our experience we have not found any specific feature in DRE. PSA levels or ultrasound examination that allows to differentiate GP from prostate cancer. Transrectal biopsy of the gland is essential for the differential diagnosis of both entities. 相似文献
36.
Z Yang S Sone P Min F Li Y Maruyama T Watanabe Y Yamaguchi 《Canadian Metallurgical Quarterly》1997,57(9):567-571
PURPOSE: To clarify the contrast enhanced CT features and anatomic distribution of the disseminated vs non-disseminated tuberculosis (TB) involving abdominal lymph nodes. MATERIALS AND METHODS: The contrast enhanced CT findings of abdominal lymphadenopathy in 25 patients, including disseminated TB associated with miliary TB of the lung (n = 5) and non-disseminated TB (n = 20), were retrospectively evaluated in a blind review to assess our criteria of morphology, density and location of the involved lymphadenopathy. RESULTS: The enhancement patterns of disseminated TB were not different from those of non-disseminated TB. Ninety-six percent of the patients had peripheral rim enhancement, and 60% showed a multilocular appearance. The enlarged lymph nodes of TB were less than 4 cm in diameter. Lymphadenopathy caused by hematogenous dissemination often accompanied splenic involvement showing multiple low-density foci in the spleen. The predominant sites of lymphadenopathy of disseminated TB were hepatoduodenal ligamentous, hepatogastric ligamentous, mesenteric, and both upper and lower portions of the retroperitoneal lymph nodes, whereas non-disseminated TB mainly involved hepatoduodenal ligamentous, hepatogastric ligamentous, mesenteric and upper retroperitoneal lymph nodes, excluding the lower retroperitoneal lymph nodes. By combining contrast enhancement patterns and the anatomic distribution of lymphadenopathy shown on the contrast enhanced CT images, reviewers made a correct diagnoses of tuberculosis in 94%, of cases, with a specificity of 95% and sensitivity of 92%. CONCLUSION: Contrast enhanced CT patterns correlate well with the pathologic features of tuberculous lymphadenopathy. A different anatomic distribution between disseminated and non-disseminated TB involving the lower retropentoneal lymph nodes was recognized in this study. 相似文献
37.
Isao Mochida Yoshihisa Sone Yang Duk Park Yozo Korai 《Journal of Materials Science》1985,20(9):3177-3183
The anisotropic development is studied of mesophase pitches prepared from modified ethylene tar (ETP) using AlCl3, of fractions separated by benzene, tetrahydrofuran (THF) and pyridine, and of mixed fractions, to find structural factors
affecting fusibility and optical anisotropy of mesophase pitch. Annealing was carried out at 360° C for 10 min. Each fraction
developed a unique optical anisotropy quite different from that of the parent mesophase pitch. The lightest fraction (soluble
in benzene) was highly fusible with small numbers of small anisotropic spheres. The heaviest fraction (insoluble in pyridine)
was infusible and exhibited a total mosaic anisotropy. In contrast, mixed fractions behaved like the parent mesophase pitch
in terms of liquid crystal behaviour. The extent of anisotropy and fusibility after annealing were strongly dependent on the
preparatory conditions of the parent mesophase pitch. The fusibility of mixed fractions is ascribed to the dissolving ability
of the fusible fraction and the solubility of the infusible fraction at the annealing temperature. Small molecules in the
lighter fractions also contribute to anisotropy when they are located in interlayer positions between the larger aromatic
molecules which constitute liquid crystals. Such co-operative properties of constituent molecules of the mesophase pitch can
be described in terms of a practical compatibility. 相似文献
38.
A cytochrome P-450 from adult pig testicular microsomes was purified to a specific content of 12 nmol P-450/mg protein. P-450 has a minimum molecular weight of 46000 +/- 1000, as judged on sodium dodecyl sulfate polyacrylamide gel electrophoresis. Adult testicular P-450 is prepared in the low-spin form with an absorbance maximum at 417 nm. The substrate-induced difference spectrum with progesterone is a typical I difference spectrum. P-450 was incorporated into liposomal membranes composed of phosphatidylcholine, and 17 alpha-hydroxylase activity was shown to amount to 15.5 nmol product/min/nmol of P-450. Furthermore, testicular cytochrome b 5 did not increase the 17 alpha-hydroxylase activity, and the activity was largely inhibited by the addition of sodium cholate, Emulgen 913 and testicular lipid. 相似文献
39.
S Sone T Tsuruo S Sato S Yano Y Nishioka T Shinohara 《Canadian Metallurgical Quarterly》1996,87(7):757-764
To develop a therapeutic modality for overcoming multidrug-resistant (MDR) cancer with anti-MDR1 antibody, we examined the effect of macrophage colony-stimulating factor (M-CSF) gene transfection into MDR AD10 cells on therapy of MDR cancer with anti-MDR1 antibody (MRK17) in nude mice. MDR human ovarian cancer (AD10) cells were transduced with the human M-CSF gene inserted into an expression vector to establish gene-modified cells capable of producing low (ML-AD10), intermediate (MM-AD10) nd high (MH-AD10) amounts of M-CSF. Systemic administration of MRK17 resulted in significant dose-dependent inhibition of subcutaneous growth of ML-AD10 tumors. In contrast, systemic administration of recombinant M-CSF in combination with MRK17 did not augment the therapeutic efficacy of MRK17 alone, but rather promoted the growth of the parent AD10 cells. To test the efficacy of in vivo M-CSF gene therapy combined with antibody, we mixed the parent AD10 cells with MH-AD10 cells producing a large amount of M-CSF, and inoculated the mixed cells subcutaneously. Treatment with MRK17 inhibited growth of the mixed cells more than that of the parent cells alone. Thus, combined therapy with anti-MDR1 mAb and M-CSF gene modification of MDR cancer cells may provide a new immunotherapeutic modality for overcoming MDR in humans. 相似文献
40.
Spontaneous pneumomediastinum (SPM) is an uncommon disorder. The mechanism of spontaneous pneumomediastinum has been speculated as follows: when air pressure in the alveoli rapidly increases, free air leaks from ruptured alveoli and accumulates along the bronchovascular tissue sheath, and then free air moves toward the mediastinum. In this case report of a 19-year-old man of SPM, a chest computed tomography (CT) revealed air in a tubular shape along the pulmonary artery in the apico-posterior segment of the left lung field. This is the first case in which the process of SPM could be identified by chest CT. 相似文献