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991.
We investigated the developmental pattern of functional synaptogenesis in the chick visual pathway using a multiple-site optical recording method. Responses to optic nerve stimulation were recorded from the diencephalon and mesencephalon of the chick embryo. The first excitatory postsynaptic responses to optic nerve stimulation appeared in the contralateral diencephalon at Hamburger-Hamilton stage 27, which corresponds to an incubation day 5.5 (E5.5). At more developed stages, the optical signals evoked by optic nerve stimulation spread to several different regions, including the tectum and extra-tectal visual nuclei. We constructed maps of neural activity in the diencephalon and mesencephalon at different stages to investigate the spatio-temporal patterns of functional development in the chick visual system. The maps revealed that distinct postsynaptic response areas in the extra-tectal regions showed different onsets of activity, suggesting that the corresponding visual nuclei exhibit different time courses of functional synaptogenesis. We also identified the onset and location of the first functional synaptic connection in the optic tectum, which had been a point of controversy in earlier studies. In the tectal region, the action potential and the excitatory postsynaptic potential first appeared at E8, although these signals were recognized in the tecto/tegmental region at E7. The response area expanded with retinotectal fibre elongation, and reached the area centralis at E9. These results show that the onset of synaptic function in the tectum occurs 2-3 days earlier than was previously reported. 相似文献
992.
Yano K Kajiya K Ishiwata M Hong YK Miyakawa T Detmar M 《The Journal of investigative dermatology》2004,122(1):201-208
We have previously shown that targeted overexpression of the endogenous angiogenesis inhibitor thrombospondin-1 (TSP-1) in the epidermis prevented chronic ultraviolet B (UVB)-induced angiogenesis and cutaneous photodamage in mice, suggesting that angiogenesis plays a critical role in the mediation of UVB effects on the skin. Nevertheless, the molecular regulation of angiogenesis factors and inhibitors by acute UVB irradiation still remains to be elucidated. We performed quantitative analyses of cutaneous vascularity and of vascular endothelial growth factor (VEGF) and TSP-1 expression after acute UVB irradiation of mouse skin. Skin vascularity in the upper dermis was greatly increased until day 8 after a single dose of UVB irradiation (200 mJ per cm2) and associated with upregulation of VEGF mRNA expression, with downregulation of TSP-1 mRNA, and with protein expression in the hyperplastic epidermis. After 13 days, skin vascularity was normalized with downregulation of VEGF mRNA expression and upregulation of TSP-1 mRNA expression to the levels observed in non-UVB-irradiated skin. In contrast, the angiogenic UVB response was prolonged in TSP-1-deficient mice. We found a pronounced induction of the TSP-1 receptor CD36 in CD31-positive vessels on day 8 after UVB irradiation, associated with vascular endothelial cell apoptosis. These results demonstrate that acute UVB irradiation leads to a shift toward a proangiogenic environment and they suggest that the balance between VEGF and TSP-1 plays a critical role in the control of angiogenesis and vascular regression induced by acute UVB irradiation. 相似文献
993.
Shumpei Miyakawa Haruo Kawamura Hajime Mishima Jun Yasumoto 《Journal of orthopaedic science》2004,9(5):462-467
We report long-term results of the first clinical trial of hydroxyapatite-coated total hip arthroplasty conducted in Japan. The hemispherical cup and the straight-tapered stem were made of titanium alloy with a grit-blasted, hydroxyapatite-coated surface. The surface roughness before and after hydroxyapatite coating was 1.4µm and 3.4µm, respectively. Thirty-three patients (35 hips) were followed prospectively; of these, 1 patient was lost to follow-up, 5 were deceased at the latest follow-up, and 27 were followed for 11 to 14 years. Two cups and one stem (two patients) were revised. Survivorship, with radiological acetabular loosening as the endpoint, was 62.3% at 14 years. At the latest radiological follow-up, stable fixation with bone ongrowth was achieved in 46% of the acetabular cups and 89% of the femoral stems. Acetabular cups with host bone coverage of less than 60% had a high rate of failure. The suboptimal result of the hydroxyapatite-coated smooth cup indicates that porous coatings under the hydroxyapatite coating would be beneficial for hydroxyapatite-coated total hip implants, especially for the acetabular components. 相似文献
994.
Expression of macrophage inflammatory protein-3alpha in an endometrial epithelial cell line,HHUA, and cultured human endometrial stromal cells 总被引:2,自引:0,他引:2
It has been demonstrated that human endometrial epithelial cells (EEC) and stromal cells (ESC) produce a variety of chemokines in vivo and in vitro. To evaluate the expression of macrophage inflammatory protein (MIP)-3alpha in endometrial cells, the production of MIP-3alpha by an EEC line, HHUA, and cultured ESC stimulated with various inflammatory mediators was evaluated by ELISA. Unstimulated HHUA and ESC constitutively secreted MIP-3alpha. Tumour necrosis factor-alpha and interleukin-1beta significantly stimulated the secretion of MIP-3alpha by HHUA and ESC. Lipopolysaccharide also stimulated the secretion of MIP-3alpha by ESC, but not by HHUA. These results show that the concentration of MIP-3alpha in the endometrium is modulated by these inflammatory mediators. MIP-3alpha may contribute to the normal and pathological processes of human reproduction by regulating the trafficking of immature dendritic cells and memory T lymphocytes into the endometrium. 相似文献
995.
Portal vein thrombosis in hypereosinophilic syndrome 总被引:4,自引:0,他引:4
Kikuchi K Minami K Miyakawa H Ishibashi M 《The American journal of gastroenterology》2002,97(5):1274-1275
996.
Uterine arteriovenous malformation: ultrasonographic,magnetic resonance and radiological findings 总被引:4,自引:0,他引:4
Nasu K Fujisawa K Yoshimatsu J Miyakawa I 《Gynecologic and obstetric investigation》2002,53(3):191-194
Uterine arteriovenous malformation (AVM) is a rare disease. However, it is important to make a rapid and precise diagnosis when it does occur, because life-threatening massive genital bleeding may occasionally be a symptom of this disease. In this case report, we present a case of uterine AVM diagnosed by means of ultrasonographic, magnetic resonance imaging (MRI) and angiographic studies. A 47-year-old Japanese woman was admitted complaining of severe hypermenorrhea that had been occurring for 5 years. Her last pregnancy was an uncomplicated term delivery at 32 years of age. Transvaginal and transabdominal ultrasonography demonstrated a thickening of the anterior wall of the uterine corpus with numerous cystic lesions. Color Doppler ultrasound, dynamic MRI and magnetic resonance angiography as well as pelvic angiography were useful for detecting the hypervascular lesions in this case. She was treated by a total hysterectomy and bilateral salpingo-oophorectomy under the diagnosis of uterine AVM. These noninvasive techniques should be performed initially when this rare disease is suspected. 相似文献
997.
Mi-Yeon Kim Kunihisa Iwai Hajime Matsue 《Journal of food composition and analysis》2005,18(8):789-802
The fruit of Viburnum dilatatum Thunb., called “gamazumi” in Japanese, has been shown to prevent oxidative injury in rats given gamazumi crude extract (GCE), a solid which was obtained from the squeezed juice. Crude protein and fat contents were very low in the squeezed juice, and GCE included 53.0 mg/g of total polyphenols. Therefore, five major phenolic compounds were isolated from GCE, which they were identified by NMR and liquid chromatography/mass spectrometry/MS. These chemical structures were as follows: cyanidin 3-sambubioside (Cy-3-sam), cyanidin 3-glucoside (Cy-3-glc), 5-O-caffeoyl-4-methoxyl quinic acid (4-MeO-5-CQA), quercetin and chlorogenic acid (5-CQA). These concentrations in the fruits were, in order, 5-CQA, 4-MeO-5-CQA, Cy-3-sam, quercetin and Cy-3-glc, and their total content was equal to 42.4% of total polyphenols. By the ESR method, the superoxide anion radical scavenging activity was in the following order: Cy-3-sam, 4-MeO-5-CQA, Cy-3-glc, 5-CQA, quercetin; and the activity on hydroxyl radicals was in the order of Cy-3-sam, 5-CQA, quercetin, 4-MeO-5-CQA, Cy-3-glc. Cy-3-sam had the most potent antiradical activity, since the activities of Cy-3-sam were similar or higher than those of ascorbic acid. Our results suggest that these phenolic compounds, especially Cy-3-sam and chlorogenic acids may contribute to the antiradical activity and physiological effects of V. dilatatum fruits. 相似文献
998.
I Miyakawa S Ichimaru C Tayama M Ito N Mori M Maeyama 《International journal of gynaecology and obstetrics》1981,19(2):89-96
The role of hormonal interactions in the mechanism initiating labor in women was studied. The serum levels in women was studied. The serum levels of cortisol, progesterone, estradiol estriol, human chorionic somatomammotropin, and prolactin were measured simultaneously before, during and after infusion of ACTH at a rate of 50 microgram/h in 100 ml of physiological saline or infusion of physiological saline without ACTH (as control) at a rate of 100 ml/h into 14 pregnant women of 10 days or more beyond term. In five (group A) of the 10 women infused with ACTH. uterine contractions were induced within 5-15 min after beginning of ACTH infusion. Although the serum progesterone levels in group A were slightly, but not significantly, lower than those in the other five women (group B) in whom uterine contractions were not induced, the ratio of progesterone to estriol was 13/1 in group A and 18/1 in group B, respectively (P less than 0.05). The endocrine levels in group A may be favorable for the initiation of uterine contraction. The serum cortisol levels in group A were higher, but not significantly higher, than those in group B after ACTH infusion. And the serum estriol levels 6 h after ACTH infusion were significantly lower than control levels before ACTH infusion (P less than 0.01 in group A, P less than 0.05 in group B). To the contrast, in all the four control women infused with physiological saline only (group C), neither uterine contractions nor changes in the serum levels of ACTH and cortisol were found. This work may show that ACTH infusion induced uterine contractions by increased corticosteroids via placenta in lower ratio of progesterone to estrogen but it does not provide any precise information on the mechanism of initiation of human labor. 相似文献
999.
Nakamura T Fukutomi T Tsuda H Akashi-Tanaka S Matsuo K Shimizu C Miyakawa K 《Japanese journal of clinical oncology》2000,30(10):453-457
We report the changes in the findings of imaging examinations (mammography, ultrasonography and contrast-enhanced computed tomography) of three patients with primary breast cancer before and after neoadjuvant chemotherapy, who obtained histologically complete responses after the chemotherapy. The neoadjuvant chemotherapy consisted of four cycles of doxorubicin and docetaxel. All patients were clinically judged as partial responders, because of the remaining tumorous lesions in the imaging examinations. However, these tumorous lesions could be related to the chemotherapy-induced fibrosis and tumor necrosis or the remaining fibrocystic changes. In this study, it was considered very difficult to estimate the extent of residual tumors accurately in patients with primary breast cancer after neoadjuvant chemotherapy by any type of imaging examination. 相似文献
1000.