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991.
T Taniguchi H Ninomiya R Fukunaga K Ebii M Yamamoto M Fujiwara 《Japanese journal of pharmacology》1992,59(2):213-220
Specific [3H]-substance P binding was saturable and of high affinity (KD = 2.5 nM) with a Bmax of 725 fmol/mg protein in the isolated rabbit iris sphincter muscle. The competition for [3H]-substance P binding was in the order of eledoisin greater than substance P greater than kassinin greater than neurokinin B greater than neurokinin A greater than physalaemin. In the same preparation, neurokinin A, as well as substance P induced a concentration-related accumulation of [3H]-inositol phosphates (IPs), and the maximum increase was about 200% of the control at 10(-4) M. [D-Arg1, D-Trp7,9, Leu11]-substance P (SP) and [D-Pro2, D-Trp7,9]-SP (10(-3) M) inhibited substance P or neurokinin A (10(-4) M)-induced phosphatidylinositol 4,5-bisphosphate (PIP2) hydrolysis significantly. [D-Arg1, D-Pro2, D-Trp7,9, Leu11]-SP (10(-3) M) also inhibited neurokinin A (10(-4) M)-induced PIP2 hydrolysis significantly. Neurokinin A and substance P produced concentration-related contractions in normal Ca(2+)-containing medium. The contractile response was weaker in Ca(2+)-free medium, and there was no response in 0.2 mM EGTA medium. In Ca(2+)-free medium, the basal level of [3H]-IPs accumulation was smaller than that in normal medium, and neurokinin A and substance P significantly increased PIP2 hydrolysis. In the 0.2 mM EGTA containing medium, neurokinin A and substance P did not stimulate the PIP2 hydrolysis.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
992.
K Fujiwara Y Naito S Higashiue Y Takagaki Y Goto M Okamoto S Yoshida H Sekii Y Tomobuchi 《The Journal of thoracic and cardiovascular surgery》1992,104(2):449-452
Narrowing of the left main coronary trunk, which was compressed by the dilated pulmonary artery, was associated with atrial septal defect in three adults. One of them had severe pulmonary hypertension. Coronary angiograms revealed localized narrowing of the left main coronary trunk, and the left main coronary trunk had a concave shape. No stenosis of other coronary arteries was observed. In all patients the atrial septal defect was closed with a polytetrafluoroethylene patch. In the patient with 75% narrowing of the left main coronary trunk, aorta-coronary bypass was performed; it was not performed in the two with 50% narrowing. In two survivors postoperative coronary angiograms showed that the narrowing of the left main coronary trunk improved or disappeared. These results suggest that markedly dilated pulmonary arteries easily compress the left main coronary trunk and cause narrowing, which improves after atrial septal defect closure. 相似文献
993.
Observation of the ocular fundus by an infrared-sensitive video camera after vitreoretinal surgery assisted by indocyanine green. 总被引:1,自引:0,他引:1
Shigeki Machida Takamitsu Fujiwara Toshihiro Gotoh Yutaka Hasegawa Akiko Gotoh Yutaka Tazawa 《Retina (Philadelphia, Pa.)》2003,23(2):183-191
PURPOSE: To investigate how long indocyanine green (ICG) dye remains in the ocular fundus and how the remaining dye interferes with ICG angiographic findings after vitreoretinal surgery assisted by ICG. METHODS: Eight eyes with macular hole, three with epiretinal membrane, and one with an intraocular foreign body were included. Those patients underwent vitrectomy facilitated by an intraocular administration of ICG. An infrared sensitive video camera was used to take fundus pictures pre- and postoperatively. In 2 of 12 cases, the authors performed ICG angiography at 2 weeks and at 3 months after the surgery. RESULTS: At 1 month after surgery, diffuse hyperfluorescence was observed throughout the posterior pole of the ocular fundus in all cases. The area where macular hole existed before the surgeries revealed hyperfluorescence in 6 of 8 eyes with macular hole (75%). These hyperfluorescent findings became less prominent with time postoperatively, while optic disk hyperfluorescence persisted for 12 months in all cases. In the early phase of ICG angiography at 2 weeks postoperatively, the retinal and choroidal circulation could be depicted. However, in the middle phase the choroidal veins were hardly visible. The angiographic pictures of the late phase mimicked those seen without intravascular administration of ICG. Even at 3 months after surgery, the optic nerve head revealed hyperfluorescence in the middle and late phases. CONCLUSIONS: The residual ICG in the ocular fundus produced prolonged hyperfluorescence after surgery. This abnormal condition affected ICG angiographic findings in the middle and late phases. 相似文献
994.
Peritumoral brain edema in meningiomas--influence of vascular supply on its development. 总被引:9,自引:0,他引:9
In a series of 35 patients with intracranial meningiomas, factors influencing the development of peritumoral brain edema (PTBE) were analyzed. We used numbers of the Edema Index as the extent of PTBE, which was obtained from the size of the meningioma and associated PTBE on a T2-weighted image of magnetic resonance imaging. We evaluated a relationship between the Edema Index and some factors that may play a role in the development of PTBE. Tumors in the frontal region and at the sphenoid ridge tended to be associated with larger PTBE than those in other locations (P less than 0.05). Histologically, meningotheliomatous and transitional meningiomas tended to be associated with larger PTBE than fibroblastic meningiomas (P less than 0.05). The meningiomas that had a vascular supply from the intrinsic cerebral arteries on angiography significantly correlated with severe PTBE compared with those supplied only from the meningeal side (P less than 0.01). We concluded that location, histology, and vascular supply from intrinsic cerebral arteries were the factors influencing PTBE. It is stressed that the vascular supply from the intrinsic cerebral arteries may have an influence on the extensive PTBE of meningioma. 相似文献
995.
Yoshiharu Nishimura Yoshitaka Okamura Keiichi Fujiwara Shuji Yamamoto Atsutoshi Hatada Takahiro Hisaoka 《Annals of thoracic and cardiovascular surgery》2004,10(4):259-262
A 47-year-old woman who had been diagnosed as having aortitis syndrome underwent aortic root replacement for an ascending aortic aneurysm and aortic regurgitation. Because the patient has been treated with steroids for more than 20 years, a Freestyle stentless valve was used to avoid the risk of valve detachment. There were no complications observed during the postoperative course. Although long-term follow-up will be necessary to observe the valve durability, the Freestyle stentless valve seems to be useful for aortic root replacement in patients at high risk of valve detachment due to aortitis syndrome. 相似文献
996.
Sun J Kang William K Scott Yi-Ju Li Michael A Hauser Joelle M van der Walt Kenichiro Fujiwara Gregory M Mayhew Sandra G West Jeffery M Vance Eden R Martin 《Movement disorders》2006,21(12):2175-2180
Monoamine oxidase (MAO) is an enzyme regulating metabolism of neurotransmitters such as dopamine. Two distinct forms of enzyme, encoded by genes MAOA and MAOB located on the X chromosome, have been considered as possible factors in the pathogenesis of Parkinson disease (PD). Previous association studies of PD and MAO genes reported inconsistent results. In this study, we used a large family-based data set to test associations between MAO genes and a risk of PD. The data set includes 298 female discordant sibpairs and 348 male discordant sibpairs. For this study, all subjects analyzed were white and families with known parkin mutations were removed. We analyzed 15 single nucleotide polymorphisms (SNPs) and a dinucleotide repeat marker in the MAO genes. Association was found with the intron 13 SNP of MAOB in the female subset (P = 0.02). No significant association was found in the male subset. Our results add to the evidence of involvement of MAOB in PD and suggest that the effect may be stronger in women. 相似文献
997.
Kakushi Matsushita Naomichi Arima Shiroh Hidaka Hideo Ohtsubo Hiroshi Fujiwara Junko Fukumori Hiromitsu Tanaka 《American journal of hematology》1994,47(2):123-128
We describe a 50-year-old man with adult T-cell leukemia complicated by laryngeal tuberculosis whose tumor cells proliferate in response to IL-2 in a paracrine manner. On admission, the patient's white blood cell count was 17,900/mm3; 73% were abnormal lymphocytes with convoluted nuclel. FACS analysis showed that the tumor cells were CD4-negative, CD8-positive T cells. Southern blot analysis of tumor cells revealed integration of a defective HTLV-I genome lacking gag and pol genes. He was diagnosed with chronic ATL complicated by laryngeal tuberculosis. The primary leukemic cells expressed IL-2Rα and IL-2Rβ detected by FACS and Northern blot analysis and showed marked growth in response to exogenously added recombinant IL-2 in short-term cultures. Northern blot analysis did not show any IL-2 mRNA. We have previously demonstrated that primary leukemic cells from some ATL patients grow in response to IL-2 in an autocrine or paracrine manner. These results suggest that in CD8 ATL, IL-2 may beinvolved in a paracrine manner. © 1994 Wiley-Liss, Inc. 相似文献
998.
Y Suzuki A Sano H Hatabu K Imanaka M Takahashi N Sadato T Tamaki K Fujiwara Y Miki K Kawakami 《Gan to kagaku ryoho. Cancer & chemotherapy》1992,19(3):323-326
Adriamycin-Lipiodol suspension was administered to 44 patients with metastatic liver tumor using the transcatheter arterial infusion method. The result revealed 23% in the over all effect (partial response or more) of the therapy which was evaluated by comparing the CT images of the tumor, 47% in the 25% or more of the decrease of the tumor, and 65%, very effective in the decrease of the smaller tumor (less than 50 cm2). Except for a case of hepatic subcapsular hematoma after the infusion of Adriamycin-Lipiodol suspension, minor complications were experienced such as abdominal pain, slight fever, and so on. No serious exacerbation in liver function test and white blood cell count was noted. 相似文献
999.
M. Fujiwara M. Okamoto K. Ijichi K. Tokuhisa Y. Hanasaki K. Katsuura D. Uemura S. Shigeta K. Konno T. Yokota M. Baba 《Archives of virology》1998,143(10):2003-2010
Summary. We have previously reported that ingenol derivatives are highly potent inhibitors of human immunodeficiency virus type 1
(HIV-1) replication in acutely infected cells. In this study, however, we have found that some ingenol derivatives strongly
enhance the replication of HIV-1 in chronically infected cells at nanomolar concentrations. One of the derivatives could activate
nuclear factor κB(NF-κB), a potent inducer of HIV-1 replication, through the activation of protein kinase C (PKC). Whereas
another derivative, which affected neither PKC nor NF-κB, significantly enhanced HIV-1 replication, suggesting that a PKC-independent
mechanism may also exist in ingenol derivative-induced HIV-1 upregulation.
Received February 23, 1998 Accepted May 21, 1998 相似文献
1000.
Yoshiyuki Ishimori Kazuhiro Yamada Hirohiko Kimura Yasuhiro Fujiwara Isao Yamaguchi Masahiko Monma Hidemasa Uematsu 《Magnetic resonance in medical sciences》2007,6(2):67-73
PURPOSE: To propose a simple and useful method for correcting nonuniformity of high-field (3 Tesla) T(1)-weighted spin-echo (SE) images based on a B1 field map estimated from gradient recalled echo (GRE) signals. METHODS: To estimate B1 inhomogeneity, spoiled gradient recalled echo (SPGR) images were collected using a fixed repetition time of 70 ms, flip angles of 45 and 90 degrees, and echo times of 4.8 and 10.4 ms. Selection of flip angles was based on the observation that the relative intensity changes in SPGR signals were very similar among different tissues at larger flip angles than the Ernst angle. Accordingly, spatial irregularity that was observed on a signal ratio map of the SPGR images acquired with these 2 flip angles was ascribed to inhomogeneity of the B1 field. Dual echo time was used to eliminate T(2)(*) effects. The ratio map that was acquired was scaled to provide an intensity correction map for SE images. Both phantom and volunteer studies were performed using a 3T magnetic resonance scanner to validate the method. RESULTS: In the phantom study, the uniformity of the T(1)-weighted SE image improved by 23%. Images of human heads also showed practically sufficient improvement in the image uniformity. CONCLUSION: The present method improves the image uniformity of high-field T(1)-weighted SE images. 相似文献