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1.
The purpose of the present study was to examine the effect of non-enzymatic glycosylation and subsequent heating on the browning of the plantar stratum corneum and the finger-nail, and to elucidate the pathogenesis of the yellow skin and the yellow nail seen in diabetic subjects. We incubated stratum corneum and nail from non-diabetics in 0 (control), 10 (only nail), 20 (only nail), 100 and 250 mM glucose buffer at 37 degrees C for 5 days. These glycosylated samples were dialysed against distilled water for 96 h. Distilled water was changed every 24 h. Then samples were dried for 24 h. The extent of non-enzymatic glycosylation was measured by furosine content. Each 5 mg of sample was hydrolysed by 6 N HCl and processed for measurement of furosine by high-performance liquid chromatography. The rest of each sample was stored at 37, 42 (only nail), 47 and 52 degrees C for 14 days. Browning of the stratum corneum was assessed macroscopically, and that of the nail by spectrophotometry. Based on their spectrophotometric reflectances. Munsell's scores (H = hue score, V = lightness score, C = saturation score) and (H + C)/V were calculated for objective evaluation of browning. Incubation of the stratum corneum and nail with glucose buffer increased their non-enzymatic glycosylation (furosine) dose dependently. Macroscopically, the browning of the stratum corneum was enhanced in proportion to the glucose concentration and storage temperature. However, samples incubated in 10 and 20 mM glucose and stored at 42 degrees C did not show visible browning. Munsell's score of the nail samples treated by glycosylation and heating showed increased hue and saturation but reduced lightness. (H + C)/V values of these nail samples were significantly higher than those of the control. We could not detect any fluorescence with Wood light in the browned samples. The present in vitro study demonstrated that the browning of the stratum corneum and the nail depended on the extent of both non-enzymatic glycosylation and storage temperature. We suggested a hypothesis that the non-enzymatic glycosylation and the storage temperature of the stratum corneum and the nail might be a contributory factor in the development of yellow skin and yellow nail in diabetic patients. 相似文献
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Staging of esophageal carcinoma in vitro with 4.7-T MR imaging 总被引:4,自引:0,他引:4
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Effect of central scotomata on pattern reversal visual evoked potentials in patients with maculopathy and healthy subjects 总被引:2,自引:0,他引:2
The effect of central scotomata on pattern reversal visual evoked potential (PVEP) was investigated in patients with maculopathy and healthy subjects. PVEP was evoked monocularly by both full-field and half-field stimulations. Since the latency of 'the major positivity at Oz' (P100-Oz) is used as the most reliable parameter in the clinical application of PVEP, special attention was focused on its changes, comparing with 'ipsilateral major positivity of half-field PVEP' (P100-IHF). Although the incidence of modification was lower in the patients, central scotomata modified PVEPs of the healthy subjects and of the affected eye of the patients in a similar manner: full-field PVEP showed prolonged latency and reduced amplitude of P100-Oz. Half-field PVEP disclosed prolonged P100-Oz latency with intact P100-IHF latency. Only difference was that amplitude reduction of both P100-Oz and P100-IHF of half-field PVEP was observed only in the healthy subjects. The prolonged P100-Oz latency of half-field PVEP was accompanied, both in the healthy subjects and in the patients, by a contralateral negative-positive complex (N105-P135) which was augmented and extended to Oz. The prolonged P100-Oz latency, thus, was due to the pronounced P135. These observations suggested that an attenuation of the afferent impulses from the central retina may cause a prolongation of the P100-Oz latency in both healthy subjects and patients, but this is not a reflection of the truly prolonged P100-IHF latency. It was concluded that, in the clinical application of PVEP, recordings of half-field PVEP from the lateral electrodes seem to be essential to distinguish true prolongation of the P100-Oz latency. 相似文献
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Kengo Yoshimitsu Hiroshi Honda Kuniyuki Kaneko Toshiro Kuroiwa Hiroyuki Irie Takashi Ueki Kazuo Chijiiwa Kenji Takenaka Kouji Masuda 《Journal of magnetic resonance imaging : JMRI》1997,7(4):696-701
Forty-nine pathologically proven gallbladder lesions were evaluated in 45 patients using dynamic MRI with a spoiled gradient pulse sequence (SPGR), to access the ability of this technique to differentiate benign from malignant gallbladder lesions. The studies were reviewed retrospectively. Signal intensity of the lesions were measured. Twenty-one malignant and 28 benign lesions were classified into three categories: polypoid, diffuse wall thickening, and exophytic. Early and delayed enhancement patterns were evaluated. For the polypoid masses, malignant lesions (n = 9) demonstrated early and prolonged enhancements, whereas benign lesions (n = 14) had early enhancement with subsequent washout (P < .05). For diffuse gallbladder wall thickening, malignant lesions (n = 6) demonstrated early and prolonged enhancement and benign lesions (n = 14) showed relatively slow, prolonged enhancement (P < .05). The exophytic masses (n = 6) all were malignant and demonstrated early and prolonged enhancement. Dynamic MRI can help differentiate benign from malignant gallbladder lesions. 相似文献
8.
The authors report a case of an 8-year-old boy with coexistent aneurysm and arteriovenous malformation (AVM) at the periphery of the left middle cerebral artery. The patient was referred to our hospital because of intracerebral hematoma in the occipital lobe. Angiography revealed an aneurysm at the periphery of the left middle cerebral artery. A small AVM was found, adjacent to the aneurysm, by histological examination of the aneurysm and surrounding tissue resected by surgery. The patient was discharged uneventfully 17 days after surgery. The association of intracranial aneurysm with AVM is reported to be seen in 1.4% of patients with intracranial aneurysms, and 6.4% to 16.7% of patients with an intracranial AVM. Three hypotheses have been proposed in order to explain the association of an aneurysm with AVM: (1) Congenital multiple disorders of vascular development, (2) Hemodynamic stress resulting from the presence of an AVM, (3) Coincidence without any causal relationship between them. The coexistence of the two vascular lesions, adjacent to each other at the peripheral cerebral arteries is rare. Only 7 cases have been reported in the literature. Four of the 8 cases including ours were children, and 6 of the 8 cases were thought to have had a hemorrhage from the AVM. It is likely that the coexistence of the two lesions in our patient is of congenital origin, because the influence of hemodynamic stress from the AVM seemed little and coexistence of the lesions as found in our case is more frequently seen in childhood. 相似文献
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Akiko Aoki Yoshiyuki Kuroiwa Yoshiaki Ishigatsubo 《Nihon Ronen Igakkai zasshi. Japanese journal of geriatrics》2003,40(2):142-146
OBJECTIVE: To evaluate the influence of the age at disease onset on the clinical symptoms, laboratory findings, treatment, and complications of microscopic polyangiitis (MPA). PATIENTS: From 1999 to 2001, we encountered 4 MPA patients with disease onset at age 65 or older (average 77.3, all were female: the elderly group). For comparison, 4 MPA patients with disease onset a 64 years or younger (average 44.7, two were male: the non-elderly group) were used. RESULTS: There was no statistically significant difference in clinical features between the two groups. All patients in the elderly group were referred to our hospital, because of fever of unknown origin or suspicion of connective tissue disease. The elderly group had a longer duration from the first admission to the start of treatment. Renal biopsies were done in all of the non-elderly group and one of the elderly group. The diagnosis of the other 3 patients of the elderly group was based on muscle or nerve biopsy, showing necrotizing vasculitis. At the time of diagnosis, antibodies to myeloperoidase (MPO-ANCA) were positive in 7 of 8 patients (87.5%). 2 patients of the non-elderly group were died of heart failure and hepatic failure by cyclophosphamide (CYC). The other 6 patients achieved substantial improvement. CONCLUSIONS: Muscle or nerve biopsy helped clinical management of elderly patients when renal biopsies could not be done. IVCY was relatively safe and effective treatment for MPA in elderly as well as non-elderly patients. 相似文献
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