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41.
Crude skin sulfhydryl oxidase was independently isolated from the living cell layer, the granular cell layer, and the lower living cell layer (spinous and basal) of cow snout. The properties of this enzyme were subsequendy investigated. The addition of 1 mM CuCl2 and FeCl2 stimulated the enzyme activity to 216% and 166% of the initial activity, respectively. Neither CaCl2 nor MgCl2 had much effect on the activity, and ZnCl2 inhibited it. Diethyldithiocarbamate (DEDTC), a copper ion chelating agent, inhibited the activity in a dose and pre-incubation time-dependent manner: however, other divalent cation chelators such as EDTA, EGTA, o-phenanthrolin and α,α'-dipyridyl did not have any effect on the enzyme's behavior. From these findings, it was determined that Cu2+ was essential for the activity of skin sulfhydryl oxidase. This enzyme was stimulated to 130–150% of its initial activity by treatment with 1 mg/ml trypsin, chymotrypsin or urokinase but was not affected by plasmin, elastase or cathepsin D. Trypsin treatment enhanced the activity in a dose and treatment-time dependent manner. Skin sulfhydryl oxidase from the lower living cell layer (spinous and basal) was more highly activated by trypsin treatment than was that from the granular cell layer. These findings suggest that this enzyme may be activated by some kind of serine proteases during the keratinocytes autolysis process in the granular cell layer.  相似文献   
42.
Recent advances in the treatment of autoimmune bullous diseases.   总被引:3,自引:0,他引:3  
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43.
44.
We have investigated the effects of recombinant rat gamma-interferon (rIFN gamma) on adjuvant-induced arthritis (AA). Lewis rats, inoculated in the left hind-paw with adjuvant (day 0), were given 10(5) U/rat of rIFN gamma daily (days 0 to 20), subcutaneously and intramuscularly on alternate days. rIFN gamma suppressed the secondary phase of swelling of both hind-paw on and after day 18 without influencing the earlier phases, both primary and secondary, of swelling. rIFN gamma also reduced the hind-paw bone lesions, the degree of splenomegaly, and the increase in erythrocyte sedimentation rate and plasma fibrinogen. These results indicate a new aspect of the regulatory role of IFN gamma in chronic inflammation.  相似文献   
45.
Atrial natriuretic peptide (ANP) is a cardiac hormone which affects endothelial cell function through a receptor-mediated process. Pneumonectomy is a common thoracic surgical procedure that can cause pulmonary oedema in the remaining lung. Few reports have investigated the aetiology of this complication. The aim of this study was to determine the changes in ANP concentration and expression of its receptors following pneumonectomy as a possible aetiology for postpneumonectomy pulmonary oedema (PPE). We compared plasma ANP concentrations, cGMP concentrations, and natriuretic peptide receptor (NPR)-A mRNA and NPR-C mRNA expression in rat lung 3 h after pneumonectomy (n=5) or a sham operation (n=5). The ANP concentrations in plasma and lung tissue in the pneumonectomy group were significantly higher than in the control group (749.5 versus 202.7 pg x ml(-1), P<0.01; 33.1 versus 6.8 ng x g(-1) wet tissue, P<0.01 respectively). The level of ANP mRNA expression in the pneumonectomy group was significantly higher than in the control group (1.44 versus 0.41 relative ANP mRNA expression, P<0.05). The concentration of cGMP and the level of NPR-A mRNA expression were not significantly different between the pneumonectomy and control groups. The level of NPR-C mRNA expression in the pneumonectomy group was significantly higher than in the control group (4.17 versus 2.19 relative NPR-C mRNA expression, P<0.01). These findings suggest that changes in pulmonary ANP and NPR-C expression may contribute to the development of PPE in the remaining lung in the acute phase following pneumonectomy.  相似文献   
46.

Purpose  

Mortality rates after pancreatic resection are now lower than 5% in high-volume centers; however, morbidity remains high. This stresses the importance of identifying accurate predictors of operative morbidity after pancreatic resection. The Estimation of Physiologic Ability and Surgical Stress (E-PASS) scoring system was developed for a comparative audit of general surgical patients. Our previous study confirmed its usefulness for predicting morbidity after pancreaticoduodenectomy. In the present study, we evaluated whether the E-PASS scoring system can predict the occurrence of complications after distal pancreatectomy (DP).  相似文献   
47.
A solid pseudopapillary tumor (SPT) of the pancreas is a rare neoplasm that mainly occurs in young women. We herein report the case of a small SPT arising from the head of the pancreas in an asymptomatic 32-year-old man, plus a literature review of this tumor. A 32-year-old man was admitted to our department at Kumamoto University Hospital for the evaluation of a pancreatic mass. The tumor had central necrosis, which was poorly perfused on contrast-enhanced computed tomography (CT) and which had a high intensity on T2-weighted magnetic resonance imaging (MRI). Histology revealed the lesion to be a solid pseudopapillary tumor of the pancreas, with the characteristic pseudopapilla formation and central degeneration. However, no capsule formation was observed. The tumor was positive for CD56, CD10, α1-antitrypsin, α1-antichymotrypsin, β-catenin, and progesterone receptor. However, the tumor was negative for pancreatic hormones, chromogranin-A, carcinoembryonic antigen, and carbohydrate antigen 19–9. We diagnosed the patient to have an SPT based on these histological findings. Small-sized solid pseudopapillary tumors of the pancreas are being increasingly recognized because of the recent advances in CT and MRI. We should also consider SPT even if it occurs in a male when the tumor contains necrosis-suspected areas which are poorly perfused on contrast-enhanced CT with a high intensity on T2-weighted MRI.  相似文献   
48.

Purpose

We aimed to examine the therapeutic efficacy of ethanolamine oleate iopamidol (EOI) as an embolic material for percutaneous transhepatic portal embolization (PTPE).

Methods

Eighty-two patients with liver tumors were treated with PTPE. Fifty-eight patients had hepatocellular carcinomas, 11 had liver metastases, and 13 had other liver tumors. A total of 55 patients (group E) were treated with 5% ethanolamine oleate after gelatin sponge administration. As a control, we evaluated 27 patients (group F) who were treated with fibrin glue and iodized oil. PTPE was mainly indicated before hepatic resection, for patients with high nontumorous volumetric resection ratios (the nontumorous volumetric resection ratio was estimated to be greater than 65% in patients with an indocyanine green retention ratio of 15 min (ICG R15) of 10% or less, and the nontumorous volumetric resection ratio was estimated to be greater than 40% in the patients with an ICG R15 of 10–20%).

Results

All patients were successfully treated percutaneously under local anesthesia. Balloon-occluded and ipsilateral approaches were used in 81 patients (99%) and 62 (75%) patients, respectively. The rate of insufficient embolization or recanalization was significantly lower in group E (7.3%) in comparison to group F (25.9%; p < 0.05). The volumetric resection ratios, before and after PTPE, decreased from 60 to 45% in group E and from 63 to 55% in group F. The post-PTPE resection ratio was significantly decreased in group E. Before and after PTPE, average ICG R15 values changed from 17 to 27% in group E and from 18 to 26% in group F. The complication rates in groups E and F were similar (7.3 vs. 7.4%).

Conclusion

EOI is a safe embolic material that can be used to induce greater liver hypertrophy, in comparison to fibrin glue, in PTPE for liver tumors.  相似文献   
49.
OBJECTIVE: Cardiac uptake of [(123)I]metaiodobenzyl guanidine (MIBG) is reduced in patients with Parkinson's disease (PD). However, the cardiac sympathetic abnormality associated with this reduction is unclear. To unmask this abnormality in PD patients we examined the functional consequences of cardiac beta-receptor activation. METHODS: Cardiovascular responses to stepwise administration of the beta1-receptor agonist, dobutamine (DOB), were assessed in 25 PD patients and 12 age-matched controls. Changes in blood pressure were compared to determine the optimal dose at which to detect denervation supersensitivity, and cardiac contractility was measured by DOB echocardiography, based on peak aortic flow velocity. The relations of these cardiovascular responses to the ratio of MIBG uptake into the heart vs. that into the mediastinum (H/M ratio) were analyzed. RESULTS: At 4 microg/kg/min DOB, systolic blood pressure increased more in PD patients than in controls (PD, 17.5+/-12.3 mm Hg; control, 7.2+/-6.2 mm Hg, p<0.01), suggesting the presence of denervation supersensitivity. At this DOB dose cardiac contractility also increased more in PD than in controls (PD, 39.0+/-15.7%; control, 23.5+/-5.2%, p<0.005) and this hyperdynamic response was significantly correlated with reduced H/M ratios (early: r=-0.63, p<0.01, delayed: r=-0.66, p<0.01). CONCLUSION: Low-dose DOB unmasks cardiac sympathetic denervation in PD patients, and decreased MIBG uptake indicates the presence of denervation supersensitivity within the heart, resulting in hyperdynamic cardiac contractility in response to a beta 1-stress condition.  相似文献   
50.
We report a patient with myasthenia gravis who had neurogenic muscle atrophy in association with external ophthalmoplegia and weakness of the upper limbs. Neurogenic changes in the limb muscles were found on needle electromyography and histological studies. Symptoms improved and atrophy of the limbs diminished after intravenous immunoglobulin and oral corticosteroid therapy. We concluded that functional interruption of the neuromuscular junction caused the neurogenic muscle atrophy and that this was relieved by appropriate therapy.  相似文献   
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