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1.
A variant of the HL-60 cell line, HL-60/MCSFR4D2, has been found to express twice the amount of PTP1C as compared to the parental HL-60 cell line by immunoblotting and immunoprecipitation. Differentiation of the variant cells after phorbol 12-myristate 13-acetate (PMA) treatment was examined by the appearance of adherence. In 1% fetal calf serum (FCS), 20% of HL-60/MCSFR4D2 cells exhibited adherence after treatment with 0.5 ng/ml PMA for 48 h, 60% exhibited adherence after treatment with 1.0 ng/ml PMA and 80% exhibited adherence after treatment with 5.0 ng/ml PMA, while HL-60 cells exhibited only a slight response. Furthermore, antisense PTP1C oligonucleotides decreased the PMA-induced adherence of HL-60/MCSFR4D2 cells. These results suggest that the high-expression of PTP1C in HL-60 cells may be involved in the enhancement of susceptibility to macrophage-like differentiation by PMA. 相似文献
2.
Basic fibroblast growth factor prevents thalamic degeneration after cortical infarction 总被引:10,自引:0,他引:10
K Yamada A Kinoshita E Kohmura T Sakaguchi J Taguchi K Kataoka T Hayakawa 《Journal of cerebral blood flow and metabolism》1991,11(3):472-478
In the focal infarction model of the rat middle cerebral artery (MCA), the thalamus of the occluded side becomes gradually atrophic, mainly because of retrograde degeneration. We determined whether basic fibroblast growth factor (bFGF) administered intracisternally could prevent this thalamic atrophy. We occluded the left MCA through a small cranial opening, and animals were then divided into two groups. One group received intracisternal injections of recombinant bFGF (1 microgram dissolved in 0.1 ml of saline with 2% rat serum) starting 1 day after occlusion and repeated once a week to a total dose of 4 micrograms by four injections. The other group received vehicle solution by the same schedule. The animals were perfused and fixed at 28 days after occlusion, and histological examination was made at the level of the caudoputamen and thalamus. In the bFGF-treated rats, the area of the posterior ventral thalamus of the occluded side was 93% of that of the contralateral side, i.e., significantly larger than in the normal saline-treated rats (75%, p less than 0.01). The infarction size was not statistically different in the two groups. Microscopic observation indicated that normal-saline-treated animals showed shrinkage and disappearance of thalamic neurons, whereas bFGF-treated groups showed preservation of thalamic neurons. Computerized analysis of the cell size substantiated this observation. To assess the effect of bFGF on astrocytes, bFGF or vehicle solution was injected into normal rats, and their histology was evaluated at 1, 2, and 4 weeks after injection. The bFGF-injected group showed a significant increase in glial fibrillary acidic protein-positive astrocytes in the brain tissue facing the ventriculocisternal system.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
3.
T Kato M Itoh J Hanashita T Itoi T Matsumoto Y Ono S Imamura N Hayakawa A Suzuki Y Mizutani Y Uchigata N Oda 《Diabetic medicine》2007,24(11):1279-1281
AIMS: A rare case of the insulin autoimmune syndrome (IAS) accompanied by insulin receptor anomaly is reported. METHODS: Antibodies to insulin and insulin receptor were determined in the patient with severe hypoglycaemia before and after the treatment with prednisolone. RESULTS: Titers of antibody to insulin and insulin receptors were 73.0% and 41.5%, respectively. Drug-induced lymphocyte stimulation tests were all negative for the suspicious drugs. Her HLA-DR was DRB1*0403/04051. Following steroid therapy, the formation of antibodies was suppressed and alleviated her symptoms. Scatchard analysis yielded findings specific to polyclonal antibodies. CONCLUSIONS: The changes in autoantibodies resulted in alleviation of the hypoglycemic symptoms as a result of steroid therapy. 相似文献
4.
Fumio Nakajima Tomohiko Asano Masamichi Hayakawa Hiroshi Nakamura 《International journal of urology》1996,3(1):s19-s21
We evaluated nitric oxide induction in antitumor therapy consisting of anti–CD3 monoclonal antibody (anti–CD3) and interleukin–2 (IL–2), then determined the effect of nitric oxide reduction with L–NG –monomethyl arginine (LNMA) on the therapeutic methods. Female C57BL/6 mice, MCA102 (a non immunogenic, NK–resistant murine fibrosarcoma cell line), and 145–2C11 (hamster anti–murine–CD3 mAb) were utilized in an experimental hepatic metastasis model developed by injecting a tumor cell suspension into the spleen of mice. A marked increase in serum NO2 – + NO1 was observed at 19 hours after anti–CD3 (10 μ, IV) and additional IL–2 administrations (40times101 U, twice, If) induced a further increase. The NO2 , + NO3- elevation in spot urine in the combination therapy was not suppressed with LNMA at a dose of 100 μg/h but was significantly lowered at 300 μg/h. The efficacy of the anti–CD3 + IL–2 therapy was not diminished by LNMA administration either at 100 μg/h or at 300 μg/h. 相似文献
5.
6.
J Hayakawa H Suzuki G Yoshida Y Usuda K Numata 《Masui. The Japanese journal of anesthesiology》1990,39(4):459-464
Arterial blood ketone body ratio (AKBR; acetoacetate/beta-hydroxybutyrate) is known as a parameter to indicate the function of the liver cells. We evaluated the effects of induced hypotension with prostaglandin E1 (PGE1) or trimetaphan (TMP) on AKBR in patients without liver disease undergoing mastectomy. Almost no change was observed in AKBR before, during and after hypotension with PGE1, but slight diminution was observed during hypotension with TMP. No hepatic dysfunction, however, developed in these patients postoperatively. These findings suggest that usual hypotension with TMP may provoke no postoperative hepatic dysfunction in patients without liver disease. For the patient who required either hypotension of long duration or hypotension with other factors affecting function of liver (surgical procedures, drugs and others), we prefer PGE1 to TMP as a hypotensive drug. We should also adopt PGE1 when cardiovascular control with hypotensive drug is necessary in patients with liver disease. 相似文献
7.
Radiotherapy for pediatric brain stem glioma: radiation dose, response, and survival. 总被引:2,自引:0,他引:2
T Hibi N Shitara S Genka T Fuchinoue I Hayakawa T Tsuchida K Nomura T Kondo K Takakura 《Neurosurgery》1992,31(4):643-50; discussion 650-1
An analysis of 39 patients under 20 years of age with brain stem glioma treated with radiotherapy between 1977 and 1991 was undertaken. Twenty-eight (71.2%) of the patients responded well to initial radiotherapy, and 11 (28.8%) responded poorly. Median survival for the total patient population was 10 months. Response rates and median survivals were influenced by radiation dose: 45.5% and 9 months at doses less than 4499 cGy (n = 11), 83.3% and 13 months at doses between 4500 and 5499 cGy (n = 12), 66.7% and 11.5 months at doses between 5500 and 6499 cGy (n = 9), and 100% and 10 months at doses more than 6500 cGy (n = 7). Multivariate analysis revealed the response to initial radiotherapy was the only predictor of survival with radiation doses up to 6499 cGy. Four of the patients who responded well demonstrated radiological and/or histological calcification within or around the tumor at the time of clinical deterioration. Radiation injury was confirmed in two autopsy cases. The possibility that intratumoral radiation injury causes clinical deterioration is suggested. 相似文献
8.
9.
Clinical significance of selective middle hepatic venography 总被引:1,自引:0,他引:1
Selective middle hepatic venography was performed in 86 patients who had been scheduled to undergo liver resection because of hepatobiliary diseases. Special catheters were used of which tips were bended counterclockwise at an angle of 45 degrees. Successful middle hepatic venograms were obtained in 65 cases (76%). Abnormal findings were observed in 27 cases (42%), and it was difficult to diagnose them by ultrasonography or computed tomography. Selective middle hepatic venogram is very useful to understand surgical anatomy of the liver in each case preoperatively. In 5 cases of giant tumor, middle hepatic venography is necessary to identify the exact site of the tumor. Selective middle hepatic venography is considered to be one of the indispensable, examinations for liver resection. 相似文献
10.
Dr. Yoshihiko Hayakawa Ph.D. Allan G. Farman B.D.S Ph.D. D.Sc. William C. Scarfe B.D.S M.S. Kinya Kuroyanagi D.D.S Ph.D. 《Oral Radiology》1996,12(1):11-18
The RVG-4 permits automatic exposure compensation (AEC). The purpose of this investigation was to determine the effects of
AEC on image contrast. Images were made either with or without a dental QA jaw phantom using a fixed image projection geometry.
Exposures were 6.3 through 27.3 μC/kg using an X-ray generator operated at 70 kVp. Region of interest pixel value distributions
were measured at tissue thicknesses in this phantom, and the average pixel values and signal-to-noise ratios (SNR) were calculated.
The use of AEC without an object in place resulted in a disproportionate relationship between pixel value and exposure with
a marked reduction in SNR. The use of AEC on under- and over-exposed images of the phantom simultaneously enhanced image contrast
and reduced SNR. Thus, AEC provides a convenient and quick method for achieving high-contrast images with sub-optimal exposures,
however, this could lead to inappropriate patient dosages if the function is used for over-exposed images. AEC reduces the
SNR and produces disproportionate pixel values relative to exposure. 相似文献