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91.
To examine the neurophysiological and cognitive characteristics of language disorder in schizophrenia, the N400 component and late positive component (LPC) of event-related potentials (ERPs) were investigated in medicated schizophrenic patients and health comparison subjects. The subjects were required to indicate whether Japanese sentence completions were semantically congruous or incongruous. The ERPs for the range of 300-500 ms to the incongruous completions contained a more negative component (N400), followed by LPC, which was inversely more positive for the incongruous than congruous condition. The N400 effect and the mean amplitude of the LPC were reduced in the patients. The attenuated N400 effect in schizophrenics mainly originated from an enhanced negativity for the congruous completions, suggesting that the use of context is poor in schizophrenia. 相似文献
92.
Nakatsuka H Ohta S Tanaka J Toku K Kumon Y Maeda N Sakanaka M Sakaki S 《Brain research》1999,849(1-2):216-219
We examined cytosolic cytochrome c in gerbil hippocampal CA1 and CA3 regions after induction of 5-min ischemia by immunoblotting. In the CA1 region, cytochrome c was detected in the cytosolic fraction from 1 to 6 h after ischemia by Western blotting, while it was not detected in the CA3 region. Following intraventricular administration of cyclosporin A (CsA), detectable cytosolic cytochrome c was dramatically decreased, and about 80% of CA1 neurons survived after ischemia. The present studies demonstrate that cytochrome c is translocated from mitochondria to the cytosol in the early stage of delayed neuronal cell death, and suggest the involvement of the mitochondrial permeability transition. 相似文献
93.
T Ohta J Zhang K Ishikawa I Tabata Y Yoshitake M Miyashita 《[Nihon kōshū eisei zasshi] Japanese journal of public health》1999,46(4):289-297
Peak oxygen uptake, ventilatory threshold (VT) and leg extension power were measured in 832 apparently healthy subjects (421 males, 411 females) aged 30-60 decades who performed medical examination at 4 health check up facilities. 1) Peak oxygen uptake was greater in male than female, and decreased with age in both sexes. Single regression formula on age were Y (ml/kg/min) = 46.6 - 0.36 x AGE, (r = 0.447, p < 0.001) in male and Y (ml/kg/min) = 35.3 - 0.23 x AGE, (r = 0.407, p < 0.001) in female. 2) VT was greater in male than female, and less decreased with age compared to maximal aerobic power. Single regression formula on age were Y (ml/kg/min) = 22.6 - 0.13 x AGE, (r = 0.371, p < 0.001) in male, Y (ml/kg/min) = 20.0 - 0.10 x AGE, (r = 0.301, p < 0.001) in female. 3) Leg extension power was greater in male than female, and decreased with age in both sexes. Single regression formula on age were Y (W/kg) = 31.9 - 0.27 x AGE, (r = 0.539, p < 0.001) in male and Y (W/kg) = 20.9 - 0.18 x AGE, (r = 0.510, p < 0.001) in female. Subjects in the present study showed height, weight and walk steps per day similar to those in National Nutrition Survey. Comparison of Peak oxygen uptake, ventilatory threshold and leg extensor power to previous studies revealed that these parameters were quite similar to the counterparts in the previous studies with less selection bias. It was suggested that subjects in this study were quite similar to normal Japanese population, and that Peak oxygen uptake, VT and leg extension power in the present study were of value for the evaluation of health related fitness in community and workplace. 相似文献
94.
Nakazato A Ohta K Sekiguchi Y Okuyama S Chaki S Kawashima Y Hatayama K 《Journal of medicinal chemistry》1999,42(6):1076-1087
sigma Receptor antagonists may be effective antipsychotic drugs that do not induce motor side effects caused by ingestion of classical drugs such as haloperidol. We obtained evidence that 1-(2-dipropylaminoethyl)-4-methoxy-6H-dibenzo[b,d]pyran hydrochloride 2a had selective affinity for sigma receptor over dopamine D2 receptor. This compound was designed to eliminate two bonds of apomorphine 1 to produce structural flexibility for the nitrogen atom and to bridge two benzene rings with a -CH2O- bond to maintain the planar structure. In light of the evidence, N, N-dipropyl-2-(4-methoxy-3-benzyloxylphenyl)ethylamine hydrochloride 10b was designed. Since compound 10b had eliminated a biphenyl bond of 6H-dibenzo[b,d]pyran derivative 2a, it might be more released from the rigid structure of apomorphine 1 than compound 2a. The chemical modification of compound 10b led to the discovery that N, N-dipropyl-2- [4-methoxy-3-(2-phenylethoxyl)phenyl]ethylamine hydrochloride 10g (NE- 100), the best compound among arylalkoxyphenylalkylamine derivatives 3, had a high and selective affinity for sigma receptor and had a potent activity in an animal model when the drug was given orally. We report here the design, synthesis, structure-activity relationships, and biological characterization of novel arylalkoxyphenylalkylamine derivatives 3. 相似文献
95.
The reductive debromination of the hypnotic (alpha-bromoiso-valeryl)urea to (3-methylbutyryl)urea by intestinal bacteria has been studied. The caecal contents of rats, mice, hamsters, guinea-pigs and rabbits had significant debrominating activity toward (alpha-bromoiso-valeryl)urea. The cell-free extract of intestinal bacteria from the caecal contents of rats had debrominating activity in the presence of both flavin mononucleotide (FMN) and NADH (or NADPH) under anaerobic conditions. Seven pure strains of intestinal bacteria were also tested and the highest activity was observed with Clostridium sporogenes. The cell-free extract of Clostridium sporogenes had debrominating activity in the presence of both FMN and NADH (or NADPH), and this activity was inhibited by sodium arsenite and potassium cyanide. The activity of the cell-free extract was also supported by the photochemically reduced form of FMN. The debromination in intestinal bacteria seems to proceed in two steps--reduction of flavins by bacterial flavin reductase(s) in the presence of NADPH or NADH, and then the reductive debromination of (alpha-bromoiso-valeryl)urea to (3-methylbutyryl)urea by bacterial dehalogenase(s) using the reduced flavins as an electron donor. These results indicate that intestinal bacteria play a role in the reductive debromination of (alpha-bromoiso-valeryl)urea to (3-methylbutyryl)urea in animals. The debromination is inhibited by oxygen and dependent on flavins. 相似文献
96.
The reductive metabolism in vivo of a flavoring additive, trans-4-phenyl-3-buten-2-one (PBO; trans-methyl styryl ketone) was investigated in rats and dogs. In both species, the double bond-reduced product, 4-phenyl-2-butanone (PBA), was detected by HPLC as the predominant species in blood after i.v. administration of PBO. PBA detected in rat blood was identified by comparison to the authentic sample. In contrast, the carbonyl-reduced product, trans-4-phenyl-3-buten-2-ol (PBOL) was also detected as a minor metabolite of PBO in both species. The area under the curve of PBOL in rat blood was only 3% of that of PBA. PBO was mutagenic in the Ames test using Salmonella typhimurium TA 100 when S-9 mix was added, but PBA and PBOL were not. It appears that PBO is mainly metabolized to PBA in vivo in rats and dogs as a detoxification pathway. 相似文献
97.
Chromatographic and spectrometric discrimination of fentanyl and its 24 analogues are discussed. Twenty-three of 25 samples were discriminated from each other by gas chromatography (GC), and the combination of GC and mass spectrometry enabled discrimination of all 25 samples. Condensed-phase infrared spectrometry was also useful for the differentiation of structurally similar compounds, but vapor-phase infrared spectra were not useful for discrimination of fentanyls. 相似文献
98.
Toshi Nomura Katsuhiro Inoue Cyrus R. Creveling Fuhito Komatsu Norio Ohta Takehiro Chino Nobuyuki Karasawa Ikuko Nagatsu 《Brain research》1996,735(2):314
Relatively large amounts of DOPA as compared with the concentration of norepinephrine are found in human dental pulp. AADC and COMT are localized in blood vessel walls of human dental pulp. This localization suggests a functional relationship between COMT and AADC with regard to the metabolism of DOPA. 相似文献
99.
Increased levels of urinary interleukin-6 in Kawasaki disease 总被引:4,自引:0,他引:4
K. Ohta A. Seno N. Shintani E. Kato A. Yachie H. Seki T. Miyawaki N. Taniguchi 《European journal of pediatrics》1993,152(8):647-649
Kawasaki disease (KD) often presents with abnormal urinary findings, such as aseptic pyuria, mild proteinuria and microscopic haematuria. In this study, we measured urinary interleukin-6 (IL-6) by a sensitive sandwich ELISA assay using mouse monoclonal antibodies against recombinant IL-6 to elucidate the role of IL-6 in the pathogenesis of renal lesions in KD. Serum IL-6 levels were increased in acute KD as well as in febrile controls. Importantly, urinary IL-6 levels were consistently elevated in patients with acute KD, but much lower in febrile controls. Urinary IL-6 levels returned steadily to normal during the convalescent phase. In addition to IL-6, urinary levels ofN-acetyl--d-glucosaminidase (NAG) and 2-microglobulin (2-mg) were also elevated during the acute phase of this disease. Eosinophils and macrophages were identifiable in urinary sediments from these patients. The increased levels of urinary IL-6 in combination with increased NAG and 2-mg seemed to suggest the presence of certain renal parenchymal lesions with cellular infiltration during the acute phase of the disease. IL-6 may serve as clinically useful parameter for the detection and monitoring of the renal involvement in KD. 相似文献
100.
T. Morioka T. Matsushima K. Ikezaki S. Nagata M. Ohta K. Hasuo M. Fukui 《Neuroradiology》1993,35(6):462-465
Two cases of intracranial adenoid cystic carcinoma mimicking meningioma are reported. In one, MRI showed not only a homogeneously enhancing extra-axial tumour attached to the dura mater of the posterior cranial fossa, but also surrounding dural enhancement, the dural tail sign. In the second, CT demonstrated a well-demarcated enhancing extra-axial tumour, indistinguishable from a sphenoid ridge meningioma extending into the orbit. The neuroradiological features of intracranial adenoid cystic carcinoma may thus closely resemble those of meningioma. 相似文献