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We examined the effects of angiotensin II (Ang II) on inward rectifier K+ currents (IK1) in rat atrial myocytes. [125I]Ang II-binding assays revealed the presence of both Ang II type 1 (AT1) and type 2 (AT2) receptors in atrial membrane preparations. Ang II inhibited IK1 in isolated atrial myocytes with an IC50 of 46 nmol/l. This inhibition was abolished by the AT, antagonist RNH6270 but not at all by the AT2 antagonist PD123319. Treatment of cells with pertussis toxin or a synthetic decapeptide corresponding to the carboxyl-terminus of Gialpha-3 abolished the inhibition by Ang II, indicating the role of a Gi-dependent signaling pathway. Accordingly, Ang II failed to inhibit IK1 in the presence of forskolin, dibutyryl-cAMP or protein kinase A catalytic subunits. In spite of the increased binding capacities for [125I]Ang II, Ang II failed to affect IKI in cells from spontaneously hypertensive rats (SHR). AT, immunoprecipitation from atrial extracts revealed decreased amounts of Gialpha-2 and Gialpha-3 proteins associated with this receptor in SHR as compared with controls. The reduced coupling of AT, with Gialpha. proteins may underlie the unresponsiveness of atrial IK1 to Ang II in SHR cells.  相似文献   
114.
Skin and soft tissue defects are sometimes problematic especially when the defects large, contaminated, irradiated, or poor blood supplied. The human mesenchymal stem cells (hMSCs) are proliferated upon basic fibroblast growth factor (bFGF) stimuli in vitro and in vivo. In this experiment, the skin and soft tissue defects are investigated if the wounds are able to be reepithelialized or accelerated by hMSCs, bFGF and porcine‐derived bilayered skin template.
1.5 × 1.5 cm2 nude rat skin and soft tissue defects including panniculus carnosus are excised and 1 × 106 hMSCs and various doses of bFGF (1–100 μg) applied. Before and after normal reepithelialization, the tissues are tested for protein expressions by immunohistochemistry and Western blotting.
The wound sizes are significantly decreased at day 7 with hMSCs with 1, 10, or 100 μg bFGF compared to hMSCs‐alone or medium‐only. All the wounds healed by day 42. 42 Kda and 38 Kda human‐derived pancytokeratin expressions, which do not cross‐react with murine antigens, by Western blotting significantly augmented by 10 μg bFGF compared to hMSCs‐alone. The epidermal immunolocalizations such as integrin α3 and SKALP (Skin‐derived Anti Leukoproteinase) are greatly elevated in time and dose‐dependent manner. Human pan‐cytokeratin expressions are immunoreactive even at day 42.
These data suggest the skin and soft tissue wound healing is accelerated by hMSCs together with bFGF, partly by means of differentiation of hMSCs toward epidermal components.  相似文献   
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Gambierol was isolated from Gambierdiscus toxicus, which causes ciguatera fish poisoning. The acute toxicological effects induced in mice by synthesized gambierol were studied. The lethal doses were about 80 μg/kg by i.p. and i.v., and 150 μg/kg by p.o. The main injury by this toxin was observed in the lung, and secondary in the heart, resulting in systemic congestion. Another toxic effect was seen in the stomach, inducing hypersecretion and ulceration. With survival from the severe stage during the initial 3 h, recovery was favorable, especially after 4 days. Additional effects were not evident during 1-week post-administration observation.  相似文献   
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Cysts and tumors of the seminal vesicle are uncommon, and their coexistence is extremely rare. We report a case of multiple papillary tumors inside a seminal vesicle cyst associated with ipsilateral renal agenesis in a 17-year-old man. Surgical excision of the cyst and tumors was performed without any morbidity and histology revealed well differentiated papillary adenocarcinoma.  相似文献   
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PURPOSE: To evaluate the treatment results of low-dose-rate (LDR) and high-dose-rate (HDR) interstitial brachytherapy (ISBT) for T3 mobile tongue cancer. MATERIAL AND METHODS: Between 1974 and 1992, 61 patients with T3 mobile tongue cancer were treated with LDR ISBT using (192)Ir hairpins with or without single pins. In addition, between 1991 and 1999, 14 patients were treated with HDR ISBT. For nine patients treated with ISBT alone, the total dose was 59-94 Gy (median 72 Gy) within one week in LDR ISBT and 60 Gy/10 fractions/5 days in HDR ISBT. For 66 patients treated with a combination therapy of external beam radiotherapy (EBRT) and ISBT, the total dose was 12.5-60 Gy (median 30 Gy) of EBRT and 50-112 Gy (median 68 Gy) within 1 week in LDR ISBT or 32-60 Gy (median 48 Gy)/8-10 fractions/5-7 days in HDR ISBT. RESULTS: The 2- and 3-year local control rates of all patients were both 68%. The 2- and 3-year local control rates of patients treated with LDR ISBT were both 67%, and those with HDR ISBT were both 71%. The local control rate of patients treated with HDR ISBT was similar to those with LDR ISBT. CONCLUSIONS: ISBT for T3 mobile tongue cancer is effective and acceptable. The treatment result of HDR ISBT is almost similar to that of LDR ISBT for T3 mobile tongue cancer.  相似文献   
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