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81.
We investigated the effects of age and naftidrofuryl oxalate (Naftidrofuryl), a 5-HT2 antagonist, on neurotransmission and transduction systems in the gerbil hippocampus using quantitative autoradiography. [3H]Quinuclidinyl benzilate (QNB), [3H]cyclohexyl-adenosine (CHA), [3H]MK-801, and [3H]muscimol were used to label muscarinic acetylcholine, adenosine A1, N-methyl-d-aspartate (NMDA), and γ-aminobutyric acid-A (GABAA) receptors, respectively. [3H]PN200-110 labeled L-type Ca2+ channels. [3H]Forskolin, [3H]cyclic adenosine monophosphate (cAMP), [3H]phorbol 12,13-dibutyrate (PDBu), and [3H]inositol 1,4,5-triphosphate (IP3) were used to label adenylate cyclase, cAMP-dependent protein kinase, protein kinase C (PKC), and IP3 receptors, respectively. Approximately 20% reductions in [3H]QNB, [3H]forskolin, and [3H]PDBu binding were observed in the hippocampus of 9-month-old gerbils in comparison with 5-week-old gerbils. Treatment with Naftidrofuryl (10 mg/kg, i.p., once a day for 7 days) ameliorated these reductions. No changes were found in [3H]CHA, [3H]MK-801, [3H]muscimol, [3H]PN200-110, [3H]cAMP, and [3H]IP3 binding. The results suggest that Naftidrofuryl may have beneficial effects on the age-related alterations in signal transmission and transduction systems in the brain. Because the acetylcholine system, adenylate cyclase, and PKC are considered to be involved in learning and memory processes, the result may have clinical implications.  相似文献   
82.
Anorectal function was evaluated in eight patients who had low anterior resection of the rectum with a low anastomotic line, using an EEA stapler, with determination of function based on periodic manometric studies and clinical symptoms. Immediately following surgery all patients suffered from frequent bowel actions and soiling. These symptoms improved with time and most patients could enjoy almost normal daily life by the sixth postoperative month. One month after surgery, anal canal resting pressure and maximum squeeze pressure were significantly reduced and rectoanal inhibitory reflex was absent; neither showed a distinct tendency to improve thereafter. Rectal sensation and reservoir capacity, which also were seriously impaired, recovered satisfactorily by the time of the six-month examination. This suggests that an improvement of clinical symptoms following this operation is dependent upon the recovery of reservoir capacity and sensation of the neorectum, and that this operative procedure is a functionally acceptable option for low rectal cancer.  相似文献   
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The characteristics of motor function and brain dopamine (DA) metabolism in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated mice after immersion immobilization stress were investigated. There was no significant difference in locomotor activities between MPTP-treated and saline-treated mice, but locomotor activities of MPTP-treated mice after stress decreased more remarkably than those of saline-treated mice. Immediately after stress, striatal DA concentrations of MPTP-treated mice were significantly lower than those of saline-treated mice. Striatal DA levels improved when 24 h passed after stress. The striatal and cortical (DOPAC + HVA)/DA ratios of MPTP-and stress-treated mice was significantly higher than that of saline-and stress-treated mice. It is due to the decreased DA level and the enhancement of DA turnover that MPTP-treated mice became remarkably akinetic after stress, and that L-DOPA therapy is not effective when the symptoms in patients with Parkinson's disease worsen due to stress.  相似文献   
86.
Recently, many papers have reported the development of severe pulmonary stenosis after an arterial switch operation (ASO) for the transposition of the great arteries (TGA) with intact ventricular septum (IVS) in the early neonate. However, supravalvular aortic stenosis after the same procedure is very uncommon. We experienced supravalvular aortic stenosis which developed gradually after successfully performing the Lecompte maneuver for TGA with IVS in a 6-day-old baby. We underwent Doty's extended aortoplasty in his 11th-month. We approached the aorta through the transection of the pulmonary trunk which was located just before the aorta. At the stenotic parts of the aorta, a discrete projection of cicatricial tissue was observed mainly at the posterior wall. The projection of the cicatricial tissue seemed to be induced as a consequence of the contraction of the aortic wall where a continuous suture was tied too tightly with non-absorbable suture materials. To prevent this complication after the Lecompte maneuver for TGA with IVS in the neonate, it is important to take care not to tie the suture too tightly and to use absorbable suture materials for construction of the aorta. There are the recommendations which we observed would prevent the post-operative complication of supravalvular aortic stenosis. As a final note, in repairing the supravalvular aortic stenosis, an approach through the transection of the pulmonary trunk was very useful.  相似文献   
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88.
Two strains of T. rubrum and one strain of T. mentagrophytes were inoculated into human skin grafted onto BALB/c nude mice by the needle puncture method. Infection was established in 1 of the 10 animals inoculated with fluffy colony type T. rubrum, 2 of the 10 animals inoculated with powdery colony type T. rubrum, and 7 of the 10 animals inoculated with granular colony type T. mentagrophytes, suggesting that the skin grafts are infectible by anthropophilic and zoophilic strains of dermatophytes. T. rubrum infection continued for a maximum of 9 weeks and T. mentagrophytes infection for more than 11 weeks. In the animals inoculated with T. mentagrophytes, fungal elements were localized in the stratum corneum of the human skin grafts. In the acute stage, microabscesses consisting of neutrophils were observed under the stratum corneum in contact with fungal elements; in the chronic stage, epidermal thickening and infiltration, mainly consisting of histiocytes and a smaller number of lymphocytes, was noted in the upper and middle dermis. Ultrastructural findings from the parasites were similar to those of dermatophytosis in man. This experimental system should be useful as a model of chronic dermatophyte infection in the human skin.  相似文献   
89.
We made an attempt to detect organic brain lesions in eight patients with myotonic dystrophy (MyD) using X-ray computed tomography (CT) and magnetic resonance imaging (MRI). The patients comprised seven men and one woman with ages ranging from 41 to 58 years (average 47 +/- 5.3 years). Seven patients had intellectual impairment assessed using an intelligence quotient test (WAIS-R < 70). CT scans were obtained in the axial plane with a slice thickness of 10 mm, and MRI scans were performed on a 1.5 tesla system in the axial and coronal sections with a slice thickness of 8 mm. CT scans displayed both marked sulcal and prominent ventricular enlargement in 6 of the 8 patients, indicating the presence of brain atrophy, and 3 cases had a few paraventricular low density area in the cerebral hemispheres. In contrast to CT, MRI study revealed more widespread brain parenchymatous lesions in all the 8 cases, showing the multiple foci of high signal intensity with varying size in the white matter on T2-weighted images and proton density-weighted images. No visible changes were detected on CT or MRI in the brain stem and cerebellum. The present study demonstrated that there exist organic cerebral lesions, predominantly located in the white matter in patients with MyD, regardless of focal neurological symptoms. The parenchymatous lesions in the brain can be detected with MRI, and lesser extent with CT, and are considered to be intimately correlated with intellectual deterioration commonly seen in patients with MyD.  相似文献   
90.
EDTA-extractable protein (EEP) is a major extrinsic protein of lens fiber membrane. The EEP of calf lens separated three major bands by SDS-PAGE, and the molecular weights of these major bands were 34 kilodalton (kd.), 33 kd. and 32 kd. Combination of EEP with F-actin and some kinds of phospholipid containing liposomes depends on Ca2+. In two-dimensional gel electrophoresis, some spots of the calf-EEP partially overlapped with spots of lipocortin, which is a substrate for epidermal growth factor receptor/kinase and an inhibitor of phospholipase A2. The 34 kd. protein of the EEP cross-reacted to the antibody prepared against lipocortin of pig's aorta: These results suggest the important function of EEP in lens.  相似文献   
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