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101.
We investigated the role of carbon monoxide as a neural modulator of extracellular glutamate concentration in rat hippocampus CA1 in transient forebrain ischemia by using metalloporphyrins, which block the production of carbon monoxide through the inhibition of heme oxygenase (HO) activity. Infusion of 10 and 100 microM zinc protoporphyrin IX, which inhibits nitric oxide synthase activity as well as HO activity, significantly increased glutamate concentration compared with that on the vehicle-treated side. However, infusion of 100 microM tin mesoporphyrin IX, which inhibits only HO activity, did not affect glutamate concentration in ischemia. Our results therefore do not support the hypothesis that carbon monoxide acts as a neural messenger through the modulation of extracellular glutamate concentration in ischemia. 相似文献
102.
103.
Transmission of respiratory syncytial virus is thought to be highly seasonal based on reported clinical cases, although transmission resulting in mild disease in all age groups has been little studied. This has been investigated in a seroepidemiological survey using sera from S?o Paulo, Brazil. Seroprevalence was found to increase rapidly with age, reaching over 90% by three years of age. This is typical of viral infections, which produce life-long immunity following primary infection. One-hundred percent seropositivity was attained by five years of age and maintained throughout adulthood, whereas mean antibody titers continued to increase with age. The mean duration of maternal antibodies was estimated to be 3.3 months with antibody decay demonstrated in paired samples from infants. The results are discussed in relation to possible mechanisms generating such a profile. 相似文献
104.
Y Terao K Hashimoto N Nukina T Mannen T Shinohara 《Canadian Metallurgical Quarterly》1996,38(5):455-460
BACKGROUND: Although there is increasing interest in the use of glycolic acid in the treatment of photoaged skin, to our knowledge, no controlled study has been done to assess the efficacy or the mode of this agent. OBJECTIVE: The purpose of this study was to determine whether 50% glycolic acid can improve photoaged skin and to study the histological basis for this improvement. METHODS: Forty-one volunteers were recruited into this double-blind vehicle-controlled study. Glycolic acid (50%) or vehicle was applied topically for 5 minutes to one side of the face, forearms, and hands, once weekly for 4 weeks. Punch biopsies were taken at pretherapy and at 5 weeks for histologic study. RESULTS: Significant improvement noted included decrease in rough texture and fine wrinkling, fewer solar keratoses, and a slight lightening of solar lentigines. Histology showed thinning of the stratum corneum, granular layer enhancement, and epidermal thickening. Some specimens showed an increase in collagen thickness in the dermis. CONCLUSION: The results of this study demonstrate that the application of 50% glycolic acid peels improves mild photoaging of the skin. 相似文献
105.
An optical sensor with a Langmuir-Blodgett (LB) film was developed for simultaneous recognition of amino acids in an aqueous solution. Anthroyloxy- stearate-containing stearate LB films and perylene-containing arachidate LB films were deposited on a quartz glass. The fluorescence of these LB films in an aqueous solution was quenched in response to amino acids. Amino acids were classified into five groups by the pattern of fluorescence quenching of anthroyloxy stearate and perylene LB films. 相似文献
106.
K Shinohara E Oeda J Nomiyama H Inoue S Kamei M Tajiri T Ichikawa T Kuwaki K Tachibana 《Canadian Metallurgical Quarterly》1995,13(4):421-427
We developed a sensitive method of measurement of granulocyte colony-stimulating factor (G-CSF) by an enzyme-linked immunosorbent assay, which we applied in the plasma of the bone marrow aspirate in 70 patients with various hematological disorders. The lowest limit of detection by this method is 2 pg/ml. G-CSF was detected in all but two of the patients. Compared to the G-CSF level in normal healthy controls, those in non-Hodgkin's malignant lymphoma, aplastic anemia, agranulocytosis and multiple myeloma were significantly higher, while the level in refractory anemia was not different. The G-CSF level in acute myelogenous leukemia patients was either elevated or decreased regardless of the French-American-British subgroup. The level in acute lymphoblastic leukemia was not different from the normal value, as was that in refractory anemia with an excess of blasts, and that in chronic lymphocytic leukemia. A patient with chronic myelomonocytic leukemia showed initial elevation of G-CSF with normalization after entering complete remission. The G-CSF level in chronic myelogenous leukemia was significantly decreased, although one patient in hematological remission who was under alpha-interferon therapy showed normal levels. The level in polycythemia vera was not significantly different from the normal value. The G-CSF level for the entire group showed an inverse, although not statistically significant, correlation with the percentages of myeloid cells of the bone marrow (r = -0.174, p = 0.1703, n = 80). These results are thought to reflect the regulatory mechanism of granulopoiesis in the bone marrow in various hematological disorders, and it is concluded that this method may be of clinical use in the treatment of patients with these disorders and in the selection of candidates likely to benefit from G-CSF administration. 相似文献
107.
JS Wolf K Shinohara KM Kerlikowske P Narayan ML Stoller PR Carroll 《Canadian Metallurgical Quarterly》1993,42(6):680-688
Indications for laparoscopic pelvic lymphadenectomy prior to radical prostatectomy have not been established. Criteria to predict lymph node metastases were derived from the preoperative evaluations of 164 prostate cancer patients undergoing pelvic lymphadenectomy. Decision analysis was used to determine which criteria would be optimal indicators for laparoscopic pelvic lymphadenectomy prior to intended radical prostatectomy. Besides a digital rectal examination suggesting uncontained tumor, which was the best indication for laparoscopic pelvic lymphadenectomy, the most useful criteria were sonographic tumor volume > or = 3 cc and prostate-specific antigen (PSA) > or = 20 ng/mL. If either parameter was met, the sensitivity for identifying patients with pelvic lymph node metastases was 88 percent and the positive predictive value was 42 percent. When both were met, the sensitivity fell to 47 percent but the positive predictive value increased to 67 percent. A combination of Gleason biopsy score and PSA was the best criterion that was independent of transrectal ultrasonography. Using a PSA > or = 15 ng/mL for tumors with Gleason biopsy score > or = 7 or a PSA > or = 25 ng/mL for tumors with a Gleason biopsy score of 5-6 had a sensitivity of 71 percent and positive predictive value of 48 percent for identifying patients with pelvic lymph node metastases. In selecting patients for laparoscopic pelvic lymphadenectomy prior to radical retropubic prostatectomy, criteria with a positive predictive value greater than 39 percent maximize the utility of laparoscopic pelvic lymphadenectomy. Prior to radical perineal prostatectomy, laparoscopic pelvic lymphadenectomy will identify pelvic lymph node metastases that would otherwise be undetected by prostatectomy alone. The sensitivity of selection criteria, therefore, should be increased, as long as the positive predictive value remains above 20 percent. 相似文献
108.
Shinohara M. Hyuga F. Kozen A. Hirano M. Tsuzuki N. 《IEEE transactions on magnetics》1985,21(1):10-13
A new kind of 1-μm bubble device with two ion-implanted layers between propagation tracks has been studied. The ion-implanted layer in the center between two adjacent propagation tracks is thinner than that in the vicinity of the propagation track edge, where bubbles adhere. The unimplanted area is produced by the use of both photoresist and Mo masks to stop the ions, whereas the thinner implanted layer is produced by the use of the thin Mo mask alone. The ion-implantation mask-making for fabricating two ion-implanted layers is achieved with a gas plasma etch procedure. This structure makes it possible to scale down a loop period and create a circuit of high density. Reliable propagation margins for minor loops with 4 × 3 μm cell sizes can be obtained. 相似文献
109.
110.
Y Shinohara I Sagawa J Ichihara K Yamamoto K Terao H Terada 《Canadian Metallurgical Quarterly》1997,1319(2-3):319-330
We isolated highly intact and tightly coupled mitochondria from the rat ascites hepatoma cell line AH130 by disruption of the cell membrane by nitrogen cavitation. These isolated mitochondria were found to have essentially the same functional properties as rat liver mitochondria, but unlike the latter, hexokinase (HK) was bound to their membrane. Using the tumor mitochondrial preparation, we examined the source of ATP for phosphorylation of glucose by HK under conditions in which intra- and extramitochondrial ATP-generation systems operated separately or together. Results showed that the membrane-bound HK utilized ATP derived from the most efficiently operating ATP generation system, i.e., oxidative phosphorylation. However, when the rate of extramitochondrial ATP generation was much greater than that of oxidative phosphorylation, HK used ATP from the extramitochondrial ATP-generation system. 相似文献