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11.
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We investigated the relative effects of 0.5, 1.0, 1.5, 2.0 MAC halothane and enflurane, and concurrent noxious stimulus on hepatic blood flow and oxygen consumption in 14 mongrel dogs randomly divided into groups of seven each. Hepatic arterial and portal venous blood flow (HABF and PVBF, respectively) were measured continuously using ultrasonic transit time flow meter. Mean arterial blood pressure (MAP), cardiac index (CI), hepatic oxygen supply, and hepatic oxygen consumption (H O 2) were measured. Halothane significantly deceased HABF, but not PVBF in a dose dependent manner. Enflurane did not affect HABF and PVBF significantly. MAP and CI decreased in both groups, with halothane producing more marked decreases than enflurane. H O 2 did not change with enflurane, but did with halothane, producing significant differences, with halothane being greater at 1.5, 2.0 MAC. A noxious stimulus only caused minor change in blood flow. The results suggest that liver blood flow and oxygen consumption are affected differently by halothane and enflurane and that halothane has a stronger tendency to cause an imbalance between liver oxygen supply and consumption than dose enflurane.(Masaki E, Yasuda N, Tanifuji Y et al.: Effect of halothane and enflurane on hepatic blood flow and oxygen consumption in dogs. J Anesth 3: 118–122, 1989)  相似文献   
13.
Recently, several angiotensin I-converting enzyme (ACE) inhibitors and an angiotensin II receptor blocker were demonstrated to have a clinically important prophylactic effect in migraine. ACE is one of the key enzymes in the rennin-angiotensin-aldosterone system, which modulates vascular tension and blood pressure. In humans, serum ACE levels are strongly genetically determined. Individuals who were homozygous for the deletion (D) allele showed increased ACE activity levels. To investigate the role of ACE polymorphism in headache, we analyzed the ACE insertion (I)/deletion (D) genotypes of 54 patients suffering from migraine with aura (MwA), 122 from migraine without aura, 78 from tension-type headache (TH), and 248 non-headache healthy controls. The ACE D allele were significantly more frequent in the MwA than controls (p<0.01). The incidence of the D/D genotype in MwA (25.9%) was significantly higher than that in controls (12.5%; p<0.01; odds ratio=5.26, 95% confidence interval: 1.69-16.34, adjusted for age and gender). No differences in the remaining groups were found. Our results support the conclusion that the D allele and the D/D genotype in the ACE gene is a genetic risk factor for Japanese MwA. There seems to be a possible relationship between ACE activity and the pathogenesis of migraine.  相似文献   
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Integrin alphavbeta5 is a receptor for vitronectin, a plasma glycoprotein that is also distributed in extracellular matrix of various tissues. Matrix-bound vitronectin has the potential to stabilize the active form of plasminogen activator inhibitor-1, resulting in the inhibition of the plasmin-mediated pericellular proteolytic cascade. In this study, we compared the levels of alphavbeta5 and matrix-bound vitronectin between normal and scleroderma fibroblasts and investigated the association with fibrosis. We demonstrated that alphavbeta5 was up-regulated on scleroderma fibroblasts. The up-regulated alphavbeta5 contributed to the increase in vitronectin-binding ability in scleroderma fibroblasts, which led to the vitronectin-dependent activation of plasminogen activator inhibitor-1. In immunohistochemistry, the alphav and beta5 subunits were stained strongly on scleroderma fibroblasts and the amount of vitronectin was increased in the pericellular matrix of those cells. The transient overexpression of alphavbeta5 on normal fibroblasts enhanced the human alpha2(I) collagen promoter activity through Sp-1 and Smad3 as well as the vitronectin-dependent plasminogen activator inhibitor-1 activity. This effect on the promoter activity was also observed in the absence of vitronectin and completely disappeared in the presence of anti-alphavbeta5 antibody. These results indicate that the up-regulated alphavbeta5 may contribute to the phenotypical alteration of scleroderma fibroblasts, while at the same time suppressing the plasmin-mediated pericellular proteolytic cascade.  相似文献   
16.
Apoptotic cell death in acinar and ductal epithelial cells is thought to play an important role in the development of salivary gland dysfunction in patients with Sjogren's syndrome (SS). We examined the expression of anti-apoptotic molecules in salivary glands from patients with SS. The labial salivary glands from six human T-cell leukemia virus (HTLV)-I-seronegative and eleven HTLV-I-seropositive SS patients were analyzed by immunohistochemistry. In vitro experiments were performed with a human salivary gland cell line (HSG cells). Immunohistologic analyses revealed that Bcl-2 and Bcl-x were preferentially expressed in salivary infiltrating mononuclear cells more than acinar and ductal epithelial cells. In contrast, strong X chromosome-linked inhibitor of apoptosis protein (XIAP) expression was evident in both acinar and ductal epithelial cells. The pattern of expression of these anti-apoptotic molecules was similar in both HTLV-I-seropositive and HTLV-I -seronegative SS patients. Western blot analysis confirmed expression of XIAP in cultured HSG cells. The expression of XIAP in HSG cells was increased by IL-1beta, TGF-beta1, or IL-10. However, XIAP expression was down-regulated by TNF-alpha, which induced apoptotic cell death of HSG cells with an increase in caspase-3 activity. These effects of TNF-alpha in HSG cells were antagonized by IL-1beta, TGF-beta1, or IL-10. Our results suggest that XIAP is important in regulating apoptotic cell death of acinar and ductal epithelial cells in patients with SS.  相似文献   
17.
An Epstein-Barr virus (EBV)-producer line, designated Akata, was established from a Japanese patient with Burkitt's lymphoma. The Akata line possessed the Burkitt's-type chromosome translocation, t(8q-; 14q+), and was derived from the tumor cell. Akata cells produced a large quantity of transforming virus upon treatment of cells with anti-immunoglobulin antibodies (Takada, 1984). Southern blot analysis of viral DNA indicated that the Akata EBV is nondefective and more representative of wild-type viruses. Akata cells should be useful as a source of EBV.  相似文献   
18.
BACKGROUND: Chronic exposure to fenoterol (FEN), a beta(2)-adrenergic receptor (beta(2)-AR) agonist, was shown to induce both airway hyperresponsiveness and airway remodeling in experimental animals. OBJECTIVE: We wanted to know the effects of chronic exposure to procaterol (PRO), a beta(2)-AR agonist, on airway function and structure, because this agent is widely used as a bronchodilator in Japan. For comparison, the effects of FEN were also examined. METHODS: Aerosolized PRO (0.1 or 1 mg/ml), FEN (1 mg/ml) or vehicle (0.9% NaCl) was given to guinea pigs 3 times a day for 6 weeks. Sublaryngeal deposition of these agents was calculated using radioisotopes. At 72 h after the last inhalation of PRO, FEN or vehicle, the dose-response relationship between lung resistance (R(L)) and intravenously administered acetylcholine (ACh) was measured. After measuring R(L), histological changes in noncartilaginous airway dimensions were evaluated. RESULTS: The amount of sublaryngeal deposition of 0.1 mg/ml PRO in the present study was speculated to be 100 times larger than that of therapeutic dose. ACh concentrations causing 2-fold, 10-fold and maximal increases in R(L) were not different in 4 groups tested. In the smaller membranous airways (<0.4 mm in diameter), but not the larger ones, thickening of adventitial areas was significantly greater in animals treated with beta(2)-AR agonists than in control animals (23 and 25, and 96% higher in animals treated with 0.1 and 1 mg/ml PRO or 1 mg/ml FEN, respectively). The degree of the increase was significantly less in PRO-treated animals than in FEN-treated animals (p < 0.01). CONCLUSION: Our results did not provide any evidence that regular inhalation of PRO at the therapeutic dose might induce bronchial hyperresponsiveness. In addition, huge amounts of PRO only caused a mild thickening of the adventitial areas, suggesting that PRO may be a weak inducer of airway remodeling compared with FEN.  相似文献   
19.
Summary Normal oesophagus specimens taken from 65 autopsy cases and surgical specimens from 127 oesophageal carcinoma cases were examined histopathologically to determine melanocyte incidence and distribution. Melanocytes were found in the epithelio-stromal junction in 7.7% of normal oesophagus specimens examined at autopsy, and in 29.9% of surgical cases with oesophageal carcinoma. Positive specimens in the latter groups, especially from pre-operatively irradiated individuals, showed a more remarkable increase of melanocytes than was evident in any of the normal oesophageal samples. There were no significant differences in incidence between males and females, or between age groups. In cases where the cancer invaded into deeper stroma, the melanocytes were mainly observed in the normal epithelium around the carcinomas. Epithelial and stromal elements of the melanotic mucosa commonly showed hyperplastic changes such as acanthosis or basal cell hyperplasia, and chronic oesophagitis. Melanocytes were observed most commonly in the lower part of the oesophagus, the site where malignant melanoma of the oesophagus, most often originates. These results strongly suggest that the melanocyte increase observed in areas of hyperplastic epithelium and chronic oesophagitis may play an important role as a precursor lesion for malignant melanoma in the oesophagus.  相似文献   
20.
Summary Distal deletion of chromosome 1q has been reported in nearly 30 patients, all being associated with a deletion ranging from the 1q42 or q43 band to 1qter region. Here, we describe a girl with 1q terminal deletion resulting from an unbalancedde novo translocation t(1;D or G)(q44; p11), as revealed by the presence of a satellited feature and an NOR-stained region at the tip of 1q. We suggest that most of the phenotypic abnormalities seen in patients with 1q distal deletion are attributable to the monosomy for band 1q44.  相似文献   
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