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71.
Y Kato H Sano K Katada Y Ogura N Kanaoka T Yokoyama T Kanno 《Canadian Metallurgical Quarterly》1996,18(2):98-102
Chronic granulomatous disease (CGD) of childhood is a rare inherited disease in which phagocytic cells fail to produce the normal respiratory burst in response to infectious stimuli, leaving the patient particularly susceptible to infections with bacteria and fungi that produce catalase. Between 1988 and 1993 at the NIH, 58 pulmonary cytology specimens were obtained on 24 CGD patients. The number of specimens per patient ranged from one to 13 with an average 2.4. The 58 specimens included: 33 bronchoalveolar lavages; one bronchial brushing; 20 lung or pleural mass fine-needle aspirates; three pleural fluids, and one sputum. Two lung aspirates with insufficient material, five bronchoalveolar lavages performed post-treatment to confirm clinical resolution of disease, and two bronchoalveolar lavages not submitted for culture were excluded from further analysis. Of the 49 remaining specimens obtained from patients clinically suspected of having a pulmonary infection, cytology demonstrated a pathogenic organism in nine (18%). Microbiologic cultures were positive in 19/49 (39%). Cytology identified fungus in 8/13 (62%) of documented fungal infections, including four cases where microbiology was negative. Bacterial and mixed bacterial/fungal infections were usually not detected by cytology even with appropriate strains. No organisms were identified by cytology in the four cases of nocardia or the three cases of pseudomonas infection. The combination of cytology and microbiology provided the greatest diagnostic sensitivity, yielding a diagnosis in 22/49 cases (45%). Of the 27 cases with negative cytology and microbiology, an infectious agent was identified in eight upon submission of additional material: three cytology specimens and five tissue specimens. In the remaining 19 cases, no organisms were identified, however, the patients were treated presumptively. Characteristic pathologic features of granulomatous inflammation, necrosis, and giant cells were present in fine-needle aspirates, often when on organisms could be identified, but were not seen in other types of respiratory specimens. 相似文献
72.
Determination of power reflectivity of quasi-graded distributedBragg reflectors using stopband width
Kurihara K. Numai T. Kosaka H. Ogura I. Sugimoto M. Kasahara K. 《Photonics Technology Letters, IEEE》1993,5(3):333-336
The authors examine the reflectivity of the quasi-graded distributed Bragg reflector using the stopband width. The stopband width of about 1000 Å for a reflectivity of about 99% is able to be measured with an accuracy of ± 1 Å. Thus, the reflectivity is determined with high accuracy from the stopband width. It is found that the quasi-graded distributed Bragg reflector is a high-quality reflector with high reflectivity and low resistance 相似文献
73.
InxGa1−xAs-based ohmic contacts which showed excellent contact properties for n-GaAs were demonstrated to be applicable to p-GaAs
ohmic contacts. These contacts, prepared by radio-frequency sputtering, provided low contact resistance (0.2 Ω-mm), excellent
thermal stability, smooth surface, and good reproducibility. The contact resistances had a weak dependence on the annealing
temperatures, which was desirable in a manufacturing view point. This weak temperature dependence was explained to be due
to a unique Schottky barrier height at the metal/p-InxGa1−xAs interface which does not depend on the In concentration in the InxGa1−xAs layer. The present experiment showed the possibility of simultaneous preparation of ohmic contacts for both n and p-GaAs
using the same contact materials. 相似文献
74.
Watanabe M. Fujiki H. Mukai S. Ogura M. Yajima H. Shimoyama K. Gotoh H. 《Quantum Electronics, IEEE Journal of》1994,30(10):2232-2234
Switching between two cross-coupled lateral modes in gain-guided twin-stripe lasers has been experimentally observed with current injection of nominally identical pulses, which strongly indicates bistability. Near- and far-field patterns at both facets are presented, which clearly shows a skewed light field which couples from under one stripe to under the other. Cross-coupled mode operation was obtained only for relatively long cavity lasers, which is consistent with the theory for twin-stripe lasers with high interstripe gain 相似文献
75.
Cyclic voltammograms of hexaamminecobalt complex have been measured in high pH solutions. The spectroscopic result suggested that hydroamminecobalt complex adsorbed on the electrode surface during cathodic polarization, and this species grew to form cobalt hydroxide after a long time of electrolysis. In the anodic process, the reaction orders for pH and NH3 were both |1|. Based on these results, the reaction mechanism has been discussed.The effect of light on the electrode process has been studied by irradiating with ultraviolet light of the 254 nm mercury resonance line. It has been indicated that the hydroxoammine complex is decomposed to cobalt hydroxide and free ligand under light. 相似文献
76.
77.
Katsuyuki Ogura 《Polymer International》1975,7(4):221-223
The temperature dependences of some selected infrared bands of poly(vinylchloride) in the vicinity of the glass transition were examined. The intensities of 1333 and 1427 cm?1 bands changed discontinuouly at Tg; on the other hand, 2920 cm?1 did not show any significant changes at this temperature. From these results, the nature of the temperature dependence of infrared intensity of the polymer was discussed. The procedure introduced in this work offers a rapid method for the determination of the Tg as compared with the conventional infrared methods. 相似文献
78.
K Tobinai T Hotta H Saito K Ohnishi R Ohno M Ogura Y Ariyoshi K Takeyama T Kobayashi Y Ohashi S Shirakawa 《Canadian Metallurgical Quarterly》1996,26(6):455-460
Irinotecan hydrochloride (CPT-11) is a new derivative of camptothecin which inhibits topoisomerase I. Phase II studies have demonstrated that CPT-11 is active against a broad spectrum of neoplasms including intractable non-Hodgkin's lymphoma. An early phase II study in lymphoma suggested that a schedule of daily infusions of 40 mg/m2/day for three or five consecutive days is more effective than a single infusion of 200 mg/m2 every three to four weeks. Carboplatin is also an active agent against lymphoma, and preclinical studies have shown that CPT-11 and its active metabolite have a synergistic effect with platinum compounds. To evaluate the maximal tolerated dose (MTD) and the therapeutic efficacy of CPT-11 in combination with carboplatin in relapsed or refractory non-Hodgkin's lymphoma, we conducted a combination phase I/II study. The starting dose of CPT-11 was 20 mg/m2/day (days 1 through 3 and 8 through 10), and dose escalations of 5 mg/m2/day increments were planned, with a fixed dose of carboplatin (300 mg/m2, day 1). Six of the eight patients receiving both agents at the starting dose level developed critical toxicities such as grade 4 hematologic (neutropenia 6/8, thrombocytopenia 1/8) and grade 3 non-hematologic toxicities (diarrhea 2/8, transaminase elevation 1/8). Further dose escalation of CPT-11 was halted, and the starting doses were judged to be the MTDs. The response rate (25%, 2/8) to the combination of the MTDs was not superior to that of CPT-11 alone in a previous phase II study (38%, 26/69), and the MTD of CPT-11 in combination with carboplatin was less than half the single-agent dose. We conclude that carboplatin is not recommendable for combination with CPT-11 in lymphoma patients. Other suitable agents for such a combination should be sought. 相似文献
79.
Pertussis vaccinations are administered worldwide under various conditions and schedules with diphtheria-tetanus-pertussis (DTP). In Japan, a general vaccination with three primary doses of diphtheria-tetanus-acellular pertussis (DTaP) at 4-week intervals and one booster dose 12 months after the primary series have been used since 1981. Decreasing the number of doses of the vaccination would lessen the physical and economic costs. To compare the immunological response to two versus three primary doses, we assessed antibody and cellular immune responses in health children. The anti-filamentous hemagglutinin (anti-FHA) and anti-pertussis toxin (anti-PT) antibody responses to two primary doses of DTaP before a booster were significantly lower than the responses to three primary doses. Although these antibody levels were low in children who received two primary doses, the FHA-induced DNA synthesis was equal to that of the children who received three doses. The anti-FHA and anti-PT antibody levels 4 weeks after the booster following two doses were similar to the levels following three doses, and high antibody titers were maintained over a long period. In areas where contact with bacteria is expected, two primary doses of DTaP may be adequate to induce the necessary level of immunological responses. 相似文献
80.
N Matsuda Y Ogura H Nishiwaki K Miyamoto T Matsubara J Kiryu Y Honda 《Canadian Metallurgical Quarterly》1996,37(11):2228-2233
PURPOSE: To report a method to evaluate leukocyte dynamics in the choroidal circulation with indocyanine green (ICG) angiography. METHODS: Nonpigmented and pigmented rats were administered ICG solution intravenously. The fundus image was obtained with a scanning laser ophthalmoscope and recorded on magnetic tapes at a video rate (30 frames/second). The images were analyzed with a personal computer-based image analysis system. RESULTS: On ICG angiography, hyperfluorescent dots were seen moving along the choroidal vessels and in the retinal vessels several minutes after injection. These fluorescent dots were thought to be circulating leukocytes stained with ICG. The micrographs of blood smears after ICG injection showed intense fluorescence of leukocytes. Computer-assisted image analysis allowed tracing of these fluorescent dots using a frame-by frame method. CONCLUSIONS: Results of this study indicated that ICG can be used for vital staining of leukocytes and that it is possible to evaluate leukocyte movement in the choroidal circulation in vivo in rats. 相似文献