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21.
Yoshimasa Mori Masakazu Takayasu Yoshio Suzuki Masato Shibuya Jun Yoshida Hiroyoshi Hidaka 《European journal of pharmacology》1997,320(2-3):183-186
The vasodilator effects of C-type natriuretic peptide (CNP) were investigated in isolated rat cerebral arterioles. CNP caused dose-dependent vasodilation, maximally by 10.0±2.2% at 10−6 M. The median effective concentration (EC50) was 5.2×10−10 M. In contrast, atrial natriuretic peptide and B-type natriuretic peptide, other members of the natriuretic peptide family, produced little or no vasodilation. Pretreatment with methylene blue (10−4 M) abolished CNP-induced vasodilation, whereas pretreatment with NG-monomethyl--arginine or indomethacin did not inhibit vasodilation. Thus, CNP is suggested to cause significant vasodilation in cerebral arterioles via a cyclic guanosine monophosphate-dependent mechanism. © 1997 Elsevier Science B.V. All rights reserved. 相似文献
22.
Takashi Ito Ryuji Sakakibara MD Tatsuya Yamamoto Tomoyuki Uchiyama Zhi Liu Masato Asahina Morihiro Higashi Kimihito Arai Shoichi Ito Yusuke Awa Kaori Yamamoto Mika Kinou Tomonori Yamanishi Takamichi Hattori 《Clinical autonomic research》2006,16(1):66-71
Abstract Uro-neurological assessment was performed in four patients with small-fiber neuropathy due to amyloidosis (2 transthyretin-type/2
immunoglobulin light-chain-type). Voiding difficulties were due to detrusor weakness and impaired bladder sensation. In two
patients cholinesterase inhibition treatment caused urge incontinence, indicating detrusor denervation supersensitivity. The
underlying mechanisms of urinary dysfunction seem to involve postganglionic cholinergic and afferent somatic nerves. 相似文献
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25.
Yoshihide Nagasako Meang Bong Jin Hiroshi Miyazaki Masato Nakayama Tsuyoshi Shimamura Hiroyuki Furukawa Michiaki Matushita Satoru Todo 《Liver transplantation》2006,12(3):435-439
Thrombocytopenia is a frequent finding following living donor hepatectomy. It appears more pronounced in right graft donors than in left graft donors. This study analyzed postoperative thrombocytopenia in 20 living liver donors and examined the change of endogenous thrombopoietin (TPO) in its recovery. Platelet count, TPO level, fibrinogen degradation product (FDP), and D-Dimer were measured before surgery and on postoperative days (PODs) 1, 2, 3, 5, 7, and 14. Concurrently, liver and spleen volumes were calculated by computed tomography. Platelet count on POD 3 was significantly lower in right graft donors than in left graft donors (13.0 +/- 3.7 x 10(4)/microL vs. 16.8 +/- 4.0 x 10(4)/microL, P = 0.039) but recovered by POD 7 in all donors. Postoperative elevations of FDP and D-Dimer were significantly higher in right graft donors than in left graft donors. TPO level rose immediately after surgery, peaked on POD 5 in left graft donors and on POD 7 in right graft donors, and fell nearly to preoperative levels by POD 14. Postoperative TPO level per liver volume was significantly higher in right graft donors than in left graft donors. In conclusion, thrombocytopenia following living donor hepatectomy resolved within the first week regardless of graft type and was mainly associated with increasing consumption of circulating platelets, possibly due to intrahepatic and splenic congestion. With a reduced number of circulating platelets, TPO level rapidly increases. Also, with reduced consumption of platelets related to recovery from surgery, thrombocytopenia should resolve. As a consequence, TPO level would be expected to fall. 相似文献
26.
ABSTRACT Embryotoxicity and teratogenicity of cadmium (Cd) and modulation of its effects by N-acetyl-L-cysteine (NAC) were evaluated in mice. Pregnant ICR mice were intraperitoneally injected with 3.5 mg/kg of CdCl2 on day 10 or 11 of gestation (vaginal plug = day 0). Pregnant mice were pretreated with 160 mg/kg of NAC intravenously 2 hours before dosing with CdCl2 . Pregnant mice were killed on day 17 of gestation. Fetuses were examined for external malformations, especially limb malformations, cleft palate and abnormal palatal rugae. There was little difference in body weight gain of dams during the gestation period in the groups treated with NAC plus Cd as compared with the groups treated with Cd alone. Pretreatment with 160 mg/kg of NAC decreased the fetal mortality, incidence of cleft palate and abnormal palatal rugae induced by Cd on day 11. On day 10, pretreatment with NAC decreased the incidence of Cd induced abnormal palatal rugae. These results clearly indicate that NAC exerts protective effects against embryotoxicity and teratogenicity of Cd. 相似文献
27.
H Yamauchi H Fukuyama S Yamaguchi T Doi M Ogawa Y Ouchi J Kimura N Sadatoh Y Yonekura N Tamaki 《Journal of nuclear medicine》1992,33(9):1637-1641
We evaluated regional blood flow and oxygen metabolism in the cerebral and cerebellar cortices of 15 patients with unilateral major cerebral artery occlusive disorders with PET. These patients showed a cortical blood flow asymmetry in middle cerebral artery distribution. Only subcortical abnormalities were detected on computed tomography. Nine patients showed crossed cerebellar hypoperfusion, a reduction in contralateral cerebellar blood flow, while six did not. No difference in the degree of cerebral blood flow asymmetry existed between the two patient groups. However, oxygen metabolism asymmetry was more pronounced and was more closely matched to blood flow asymmetry in patients with crossed cerebellar hypoperfusion. These findings suggest that a major cause of cerebral cortical blood flow reduction is reduced metabolic demand in patients with crossed cerebellar hypoperfusion. Crossed cerebellar hypoperfusion may have clinical significance as a reflection of the cerebral metabolic state on blood flow images. 相似文献
28.
Y Fujibayashi Y Takemura K Matsumoto K Wada Y Yonekura J Konishi A Yokoyama 《Journal of nuclear medicine》1992,33(4):545-549
In view of the high binding ability of cardiac glycosides to the myocardial Na,K-ATPase, radioiodinated digoxin derivatives were surveyed as candidates for myocardial imaging, with particular emphasis on the noninvasive monitoring of cardiac glycoside therapy. Among the radioiodinated digoxin derivatives surveyed, 125I-digoxin-iodohistamine(bis(O-carboxymethyloxime)) showed the highest accumulation in the myocardium and similar binding ability to Na,K-ATPase as digoxin itself against ouabain displacement, as indicated by in vivo and in vitro studies. Based on these results, 123I labeling of digoxin-histamine(bis(O-carboxymethyloxime)) and imaging in a dog demonstrated uptake in the myocardium. 相似文献
29.
Masafumi Ogawa Yasuhiro Magata Yasuomi Ouchi Hidenao Fukuyama Hiroshi Yamauchi Jun Kimura Yoshiharu Yonekura Junji Konishi 《Brain research》1994,650(2):249-252
The effect of the cholinergic blocker, scopolamine on the cerebral blood flow (CBF) response to vibrotactile stimulation of a fore paw was studied using high-resolution positron emission tomography and H215O in 5 pentobarbital-anesthetized cats. Before scopolamine injection, the CBF response to the stimulation was found in the contralateral somatosensory cortex (mean ratio (contralateral/ipsilateral) control: stimulated1.02 ± 0.02: 1.17 ± 0.05; P < 0.01). After intravenous injection of scopolamine (0.35 mg/kg), the CBF response was abolished. However, the cerebral metabolic rate of glucose (CMRGlu) response to the same stimulation was unchanged after scopolamine injection in the same cats. We concluded that scopolamine abolishes the CBF response but not neuronal response to stimulation. We suggest that cholinergic mechanisms may play an important role for mediating CBF coupling to neuronal activity during physiological stimulation. 相似文献
30.
Yoichi Kikuchi Taku Sakurada Masato Suzuki Tomoyasu Hirano Katsuyuki Kusajima 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2004,52(8):375-378
Off-pump coronary artery bypass grafting has become an attractive surgical alternative for myocar-dial revascularization because
of the advantage of myocardial protection and other benefits of patients. However, it is still regarded as a controversial
treatment for the coronary artery disease accompanied by atrial fibrillation (AF). A significant number of patients in need
of coronary revascularization have chronic AF. Although the Cox-Maze III procedure is the gold standard for the surgical treatment
of AF, few of these patients undergo AF operations at the time of their coronary bypass grafting. We report herein a case
of the pulmonary vein isolation to eliminate the AF by means of epicardial radiofrequency ablation combined with 2 vessels
coronary artery bypass grafting on the beating heart with the aid of cardiopulmonary bypass. 相似文献