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991.
Y Moriyama Y Morishita H Toyohira S Shimokawa Y Umebayashi H Saigengi S Kawashima A Taira 《Kyobu geka. The Japanese journal of thoracic surgery》1990,43(7):538-542
Four patients with descending thoracic aortic aneurysm were successfully operated on under temporary bypass with an antithrombogenic tube and a Bio-Medicus centrifugal pump. The bypass flow ranged from 1.0 to 2.4 l/min with the mean femoral artery pressure of 50 to 70 mmHg. No complications such as paraplegia, hepatic dysfunction or renal failure were encountered in all the patients. Temporary increment of the serum amylase level occurred in all the patients, but any apparent clinical symptoms were not present. The temporary bypass method with an antithrombogenic tube and a centrifugal pump is useful and reliable for surgical treatment of descending thoracic aortic aneurysm. 相似文献
992.
Y. Tani T. Ishihara T. Kanai T. Ohno J. Andersson A. Lilja G. Antoni K. -J. Fasth P. Bjurling G. Westerberg P. Hartvig H. Onoe Y. Watanabe B. Langström 《Journal of neural transmission (Vienna, Austria : 1996)》1995,102(3):189-208
Summary The effects of 6R-L-erythro-5,6,7,8-tetrahydrobiopterin (R-THBP) on the central cholinergic and dopaminergic systems in the Rhesus monkey brain were investigated by positron emission tomography (PET) with the muscarinic cholinergic receptor ligands (N-[11C]methyl-benztropine) and dopaminergic receptor ligands selective for D1 D2, and D3 subtypes ([11C]SCH23390, N-[11C]methyl-spiperone, and (+)[11C]UH232, respectively). None of the doses (3, 10, and 30 mg/kg i.v.) of R-THBP used significantly affected the regional cerebral blood flow (rCBF as determined by Raichle's H2
15O method), and 10 mg/kg of R-THBP had little effect on the regional cerebral metabolic rate of glucose (rCMRglc) in the Rhesus monkey brain, as assessed by the graphical [18F]fluoro-deoxyglucose method. The effect of R-THBP on the muscarinic cholinergic system was dose dependent; while 3 mg/kg of R-THBP did not significantly alter the uptake ratio of N-[11C]methyl-benztropine in several brain regions to that in the cerebellum, 10 and 30 mg/kg of R-THBP significantly reduced the uptake ratio in the thalamus, as well as in the frontal and temporal cortices. None of the doses (3, 10, and 30 mg/kg i.v.) of R-THBP tested affected [11C]SCH23390 (dopamine D1 receptor) binding. However, the k3 value for N-[11C]methyl-spiperone (dopamine D2 receptor) binding, which represents the association rate × Bmax value, was significantly decreased in the striatum. The uptake ratio of (+)[11C]UH232 (dopamine D3 receptor) in the striatum to that in the cerebellum was also decreased by administration of R-THBP (3 and 30 mg/kg i.v.). These findings suggest that R-THBP acts on dopamine D2 and D3 receptors selectively without markedly affecting dopamine D1 receptor binding. Furthermore, the changes in cholinergic and dopamine D2 and D3 receptors in vivo can not be attributed to a change in rCBF but may depend on the action of R-THBP.Abbreviations
R-THBP
6R-L-erythro-5,6,7,8-tetrahydrobiopterin
-
PET
positron emission tomography
-
rCBF
regional cerebral blood flow
-
rCMRglc
regional cerebral metabolic rate of glucose 相似文献
993.
Secondary retinitis pigmentosa and cerebral demyelination in Lyme borreliosis. 总被引:2,自引:1,他引:1
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A Karma T A Pirttil M K Viljanen Y E Lhde C M Raitta 《The British journal of ophthalmology》1993,77(2):120-122
A 15-year-old girl developed retinitis pigmentosa-like fundus changes in the left eye and optic neuropathy in the right eye as well as cerebral demyelination as a result of late Lyme borreliosis (LB). The diagnosis was confirmed by polymerase chain reaction, which detected a Borrelia burgdorferi specific segment of a gene coding for 41 kD endoflagellin, both in the vitreous and the cerebrospinal fluid. The diagnosis was delayed because testing for Borrelia antibodies in serum and cerebrospinal fluid yielded negative results. However, later on, another laboratory reported the antibodies of the patient's pretreatment serum to be positive for LB. 相似文献
994.
Scrofuloderma (tuberculosis colliquativa cutis) 总被引:1,自引:0,他引:1
Summary A 16-year-old girl presented with long-standing purulent sinuses to the skin overlying the lacrimal ducts, which had evolved into ulcers and resulted in hypertrophic scarring. The ulcers were serpiginous, with an uneven soft floor, and undermined edges. Histological examination revealed non-caseating tuberculoid granulomas in the dermis. Cultures for Mycobacterium tuberculosis were positive. Chest X-ray did not show pulmonary involvement. Antituberculous therapy with isoniazid 300mg/day and rifampicin 600mg/day achieved a great improvement within 5 weeks of being started. A further improvement was seen at 4 months and complete resolution had occurred by 9 months. To the best of our knowledge, there are no other documented cases of scrofuloderma over the lacrimal system. The delay in the diagnosis emphasizes the importance of maintaining a high level of awareness. 相似文献
995.
A developmental study of interphotoreceptor retinoid-binding protein (IRBP) in single and double homozygous rd and rds mutant mouse retinae 总被引:1,自引:0,他引:1
T van Veen P Ekstrom B Wiggert L Lee Y Hirose S Sanyal G J Chader 《Experimental eye research》1988,47(2):291-305
Interphotoreceptor retinoid-binding protein (IRBP) was studied using immunochemical and immunocytochemical techniques in retinae of mice with allelic combinations at the rd and rds loci at different stages of development and degeneration. Until postnatal day 7 (P7), IRBP is located intracellularly in developing retinae of the different genotypes. Thereafter, IRBP is present mainly in the interphotoreceptor matrix. As previously noted, cell death is slowest in the heterozygous +/+,rds/+ mutant with loss increasing in order in +/+,rds/rds, rd/rd, rds/rds and rd/rd,+/+ animals. The IRBP content of the total retina also approximates this pattern, with lowest amounts by far in rd/rd, rds/rds and rd/rd,+/+ mutants (after P14). Interestingly though, IRBP loss significantly precedes visual cell loss in the rd/rd,rds/rds retina. In all the mutants, the remaining rod cells in the outer nuclear layer exhibit synthesis of intracellularly located IRBP at late stages of degeneration. In the single homozygous rd/rd,+/+ and the double homozygous rd/rd,rds/rds mutants, IRBP is present intracellularly during the entire degenerative process with somewhat less intracellular IRBP in the rd/rd,rds/rds mutant. Retinae of homozygous +/+,rds/rds and heterozygous +/+,rds/+ animals exhibit a normal distribution pattern of IRBP immunoreactivity until loss of photoreceptor cells becomes pronounced at later stages of the disease. Many of the remaining cells at this time are probably cone elements although they are structurally changed. Double labeling with IRBP and S-antigen demonstrates, in many but not all, the presence of both proteins in the same cell body. Immunocytochemistry clearly demonstrated the presence of IRBP in remaining photoreceptor cells at late stages of the disease. Thus, the biochemically measured loss of IRBP appears to be a complex process neither directly dependent on the loss of photoreceptor outer segments and reduced interphotoreceptor matrix space (e.g. there is a sustained IRBP level in rodless rds mutants) nor simply due to cell death (e.g. in the rd/rd,rds/rds mutant, IRBP loss significantly precedes cell loss). That this IRBP is mainly intracellular, however, may indicate an abnormality in secretion which, combined with other factors, induces a degenerated and less differentiated phenotype. 相似文献
996.
Fifty-one patients with raised intraocular pressure (IOP) were treated for up to four years with one of three ophthalmic solutions: 0.5% levobunolol, 1% levobunolol, or 0.5% timolol. The study was conducted as a double-masked, randomised trial in which medications were administered twice daily to both eyes. Levobunolol and timolol were equally effective in reducing overall mean IOP; reductions were greater than 8.8 mmHg in all three treatment groups. The study showed levobunolol to be as safe and effective as timolol in the long-term control of raised IOP. 相似文献
997.
998.
K Imaida C Furihata M Tatematsu C H Yoon F Furukawa C Uneyama M Takahashi N Ito Y Hayashi 《Toxicologic pathology》1991,19(3):230-236
Pepsinogens are acid protease enzymes of pepsin usually found in gastric mucosa. In the present study, we demonstrated the presence of pepsinogen isozymes in male Syrian golden hamster lung tissues by a combined immunohistochemical and biochemical approach. Immunohistochemically, using rat pepsinogen 1 antibody, pepsinogen positive cells were observed mainly in the epithelia of the terminal bronchioles. They demonstrated morphological features of Clara cells. The pepsinogen isozyme pattern of lung tissue determined by polyacrylamide gel electrophoresis was similar to that of stomach mucosa. Treatment of hamsters with polychlorinated biphenyls at a dose of 500 mg/kg body weight ip caused a 2.8-fold increase in pepsinogen content (p less than 0.01) as well as increase in numbers of pepsinogen positive cells in the lung. 相似文献
999.
Expression of epidermal growth factor and fibroblast growth factor in human hepatocellular carcinoma: an immunohistochemical study. 总被引:5,自引:0,他引:5
Expression of epidermal growth factor (EGF) and fibroblast growth factor (FGF) was examined in 56 patients with hepatocellular carcinoma (HCC) using an immunohistochemical method. EGF and FGF were expressed on carcinoma cells in 14 (25%) and 23 cases (41%), respectively. In the 23 FGF-positive cases, 11 cases were positive for both acidic and basic FGF, while 18 were positive for acidic FGF, and 16 were positive for basic FGF. In non-cancerous hepatic tissues, FGF was weakly positive in macrophages, hepatocytes and vascular endothelial cells in some cases, while EGF was totally negative. There were no significant correlations between the expression of EGF or FGF on carcinoma cells and the various clinicopathologic factors examined. These data suggest that EGF and FGF are produced by human HCC cells in vivo. The roles of the expression of these growth factors in the development and progression of HCC remain only speculative. 相似文献
1000.
The rat lung and nasal cavity are two target organs for carcinogenesis by 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). In order to characterize further the enzymes involved in the bioactivation of NNK, detailed kinetic and inhibitory studies were conducted with rat lung and nasal mucosa microsomes, and the results were compared with previous studies. The enzymes in rat lung microsomes catalyzed the alpha-hydroxylation, pyridine N-oxidation and carbonyl reduction of NNK. The apparent Km for the formation of the NNK-derived keto aldehyde, NNK-N-oxide, the NNK-derived keto alcohol and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol were 28.8, 10.4, 7.0 and 178.1 microM respectively. In rat nasal microsomes, alpha-hydroxylation was the predominant pathway and the rate was approximately 200 times higher than that in lung microsomes. The apparent Kms for keto aldehyde and keto alcohol formation in rat nasal microsomes were 9.6 and 10.1 microM respectively. The cytochrome P450 inhibitors metyrapone and carbon monoxide markedly inhibited the metabolism of NNK in both rat lung and nasal microsomes. In rat lung microsomes, alpha-naphthoflavone and monospecific antibodies against P450s 1A2, 2A1 and 2B1 inhibited the formation of keto aldehyde by 39, 46, 64 and 23% respectively. In rat nasal microsomes, alpha-naphthoflavone and antibodies against P450s 1A2, 2A1 and 3A inhibited the metabolism of NNK by 80, 35, 20 and 14% respectively. The results indicate that cytochromes P450 play a major role in the metabolic activation of NNK in rat lung and nasal microsomes, and that there are tissue-related differences in NNK metabolism. 相似文献