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31.
AIM: Recent studies have shown that various factors contribute to the increased excitability into the bladder afferent nerves in spinal cord injury (SCI) rats. It has been reported that prostaglandins (PG) act as local modulators of reflex micturition in pathological conditions. In the present study, we measured the amount of PGE2 release from the bladder of chronic SCI rats. METHODS: Spinal cord was transected at the level of T8-9 in adult female Sprague-Dawley rats. After 10 weeks, specimens of the urinary bladder were obtained from SCI rats and sham-injured control rats, and bladder strips were dissected from the bladder. Using an muscle-bath technique and a microdialysis procedure, the dialysate, containing substance released from bladder strips, was collected. Then the amount of PGE2 in the dialysate was measured by radioimmunoassay. RESULTS: Excretion of urinary PGE2 was significantly higher in SCI rats than in control rats. PGE2 release from bladder strips was significantly higher in SCI rats than in control rats. Removal of urothelium caused significant decreases in PGE2 release in both control and SCI rats. Stretches of the bladder strips caused significant resting tension-dependent increases in PGE2 release from the strips with urothelium. CONCLUSIONS: The present data suggest that bladder urothelium partly contributes to the increase in PGE2 release from the bladder, and that bladder distension may cause increases in PGE2 release in SCI rats.  相似文献   
32.
Ocular membranes have been characterized by in-situ absorption of the ophthalmic β-blockers carteolol (hydrophilic) and timolol and befunolol (lipophilic) using a cylindrical cell. After introduction of drug solution into the cell on the cornea, sclera (bulbar conjunctival and scleral layer) or palpebral conjunctiva, the disappearance of the drug from the cell was determined as in-situ absorption. The ophthalmic drugs disappeared from the conjunctival and scleral membranes although disappearance from the cornea was hardly observed. The conjunctival membrane showed the highest permeability. Lipophilic drugs were more permeable than hydrophilic. In-situ apparent permeability coefficients of the ophthalmic drugs through the conjunctiva and sclera correlated with the lipophilicity of drugs. A high drug concentration in the aqueous humor was observed after corneal application. There is a relationship between concentrations of drugs in the aqueous humor and previously reported in-vitro apparent permeability coefficients of the drugs in the cornea. This in-situ method using a cylindrical cell is a useful method of investigating the ocular absorption of ophthalmic drugs.  相似文献   
33.
Abstract  The activated cerebral regions and the timing of information processing in the hemispheres was investigated using event-related potentials (ERP) and regional cerebral blood flow (rCBF) as the neurophysiological indicators. Seven men and one woman (age 19–27 years) were asked to categorize two-syllable Japanese nouns (verbal condition) and to judge the difference between pairs of rectangles (spatial condition), both tests presented on a monochrome display. In the electroencephalogram (EEG) session, EEG were recorded from 16 electrode sites, with linked earlobe electrodes as reference. In the positron emission tomography (PET) session, rCBF were measured by the 15O-labeled H2O bolus injection method. Regions of interest were the frontal, temporal, parietal, occipital and central lobes, and the entire cerebral hemispheres. When the subtracted voltages of the ERP in homologous scalp sites were compared for the verbal and spatial conditions, the significant differences were at F7-F8 and T5-T6 (the 10–20 system). The latencies of the differences at T5–T6 were around 200, 250 and 320 ms. A significant difference in rCBF between the verbal and spatial conditions was found only in the temporal region. It was concluded that early processing of information, that is, registration and simple recognition, may be performed mainly in the left temporal lobe for verbal information and in the right for spatial information.  相似文献   
34.
Accidental transmission of contagious pathogens, especially hepatitis C virus (HCV), by needlestick or other means as an occupational hazard for medical staff is of concern. We retrospectively analysed cases of work-related accidental injury with pathogens such as hepatitis B virus (HBV), HCV, syphilis and human immunode?ciency virus (HIV) reported to the centres for disease control at 15 hospitals (total 5776 beds) in the Gunma prefecture, Japan, from December 1990 to August 1993 (24.7 months). There were 416 such cases (16.8 cases/month), with an incidence of 0.2–3.5 accidents per month per hospital. Such accidents occurred in 297 (71.2%) nurses, 98 (23.5%) medical doctors, 13 (3%) laboratory technicians, four (1.0%) hospital maintenance workers, one (0.2%) assistant nurse, one secretary and two others. There were 323 (77.6%) injuries caused by needlestick, 42 (10.1%) from suture needles or surgical knife cuts, 17 (4.1%) from blood splatters from patients into the eyes or mouth, 10 (2.4%) from contact with injured skin and 24 (5.8%) simple skin contacts. Of the pathogens, 60.3% were HCV, 22.6% HBV, 5.8% syphilis, 0.7% HIV and 10.6% were of unknown origin. Four cases (1.6%) of HCV infection were found and treated with one or two courses of interferon therapy, and HCV was subsequently cleared. All four patients were cured with interferon therapy. None of the HBV-injured cases resulted in infection, possibly because of prophylaxis with HB immunoglobulin and HB vaccine. No HIV or syphilis infection was contracted. In summary, chronic HCV infection acquired as an occupational hazard can be cured by appropriate treatment, such as with interferon, after early detection of the infection.  相似文献   
35.
Two patients with adenosquamous cell carcinoma of the colon,who presented severe hypercalcemia, are reported. Adenosquamouscell carcinoma of the colon is relatively rare, and there wereonly two cases among 1,053 patients who were hospitalized withmalignancy in the large intestine at the National Cancer CenterHospital during the past 18 years. Both of these cases presentedlethal hypercalcemia in the absence of osseous metastasis, andthere were no other patients who had malignant tumors of thelarge intestine and presented hypercalcemia. These observationssuggest that there is a close relationship between the squamouscell component and the occurrence of hypercalcemia, as is observedin the case of lung cancer. Radioimmunoactive parathyroid hormonewas undetectable in the plasma and the tumor tissue in thesetwo cases.  相似文献   
36.
Multinucleate epidermal cells (MEC) originated from keratinocytes were observed histologically in 92 of 197 cases of non-neoplastic dermatoses, such as lupus erythematosus (26 of 70), lichenoid eruptions (26 of 47), Hailey-Hailey disease (5 of 5), psoriasis vulgaris (20 of 49) and so on. Most of these cells had two nuclei, and a few had three nuclei. MEC usually showed perinuclear bands of eosinophilic material which also showed positive staining for epidermal fibres (tonofilaments). In all cases of Hailey-Hailey disease, close correlation between formation of MEC and dyskeratotic tendency was observed. From these findings, it is concluded that the mechanism of formation of MEC in these dermatoses may be similar to that of Bowen's disease, in which dyskeratotic tonofilaments become entangled with the spindles of the mitotic apparatus so that normal cell division cannot take place. It seems likely that MEC are a manifestation not only of malignant dyskeratosis but also of benign one.  相似文献   
37.
In a series of 2,013 gastric polyps in 1,201 patients, morphological and histopathological studies have been performed. Ninety-three hyperplastic polyps in 56 patients have been followed-up endoscopically and histopathologically for five to 12 years. The incidence of detection of gastric polyps has increased: 1.4% in 1967 to 8.7% in 1979 year by year. Thirty patients (54%) among the 56 showed changes in number, size or shape of polyps during follow-up. Twenty patients (37%) revealed numerical changes (increase in 16 patients, reversion in three patients and vanishing in two patients).
Twenty-eight polyps (30%) showed morphological changes, six of them showed continuous enlargement, 18 lesions repeated enlargement, stationary or reduction stages, three lesions were reversed and two polyps disappeared.
Histopathologically, three lesions showed transformation from the hyperplastic type to adenoma while demonstrating morphological enlargement. Two of these showed increase in cellular atypia, from the hyperplastic type through adenoma with severe atypia and finally to carcinoma in the polypectomy specimens. From this study, it was concluded that although hyperplastic polyps show changes in size, shape or number with passage of time, malignant changes occur in only a few cases.  相似文献   
38.
The aims of this study were to define the antagonistic effects of atropine sulfate to halothane-induced cardiovascular depression in children, and to clarify whether or not a larger dose of atropine is more effective in attenuating the cardiovascular depression. Thirty-four children aged 1–12 years who had undergone minor surgery, free from cardiac or pulmonary disease, were assigned at random to two groups. M-mode echocardiographic evaluation of left ventricular function in each patient was performed at three points (before induction, point A; after induction, point B; and following administration of atropine, point C). Results were compared between points A and B, B and C and C and A, and between the two study groups with different doses of atropine (0.01 mg/kg vs 0.02 mg/kg). Heart rate (HR), mean blood pressure (MBP) and left ventricular shortening fraction (LVSF) decreased, and left ventricular end-diastolic dimension (LVEDD) were increased significantly by halothane induction. Although HR and MBP recovered following atropine, LVSF and LVEDD remained unchanged. There were no differences found between the values after vagolysis in both study groups, except for HR and mean velocity of circumferential fiber shortening (mVcf). Heart rate increased above that of pre-induction, even following the smaller dose of atropine. The myocardial depression cannot be necessarily attenuated by vagolysis regardless of the dosage of atropine. The smaller dose (i.e. 0.01 mg/kg) seems to be sufficient only to antagonize the bradycardia and hypotension during halothane anesthesia in children.  相似文献   
39.
To evaluate the effectiveness of endoscopic surgery for life-threatening large brain hemorrhage, we reviewed our empirical cases of comatose patients with large supratentorial intracerebral hemorrhage. Among 35 patients with putaminal or subcortical hemorrhage that was evacuated endoscopically, 14 cases (40%) presented both findings of neurological grade IV for severity and hematoma volume exceeding 70 mL in the recent 3 years (endoscope group), whereas 8 cases with the same conditions were treated by conventional craniotomy for the preceding 3-year period (craniotomy group). Between these two groups, mean age was higher and duration of surgery was shorter in the endoscope group, but no significant differences in hematoma size or evacuation rate were recognized. In the 10 cases that presented with signs of cerebral herniation (neurological grade IVb) and required emergent decompression, the preparation time for surgery tended to be shorter in the endoscope group, although the difference was not significant. Additional ventricular drainage was performed in 7 cases and showed a supplemental effect of reducing intracranial pressure (ICP). Consequently, all patients in the endoscope group were rescued without decompressive large craniectomy, even with symptoms of cerebral herniation. In conclusion, endoscopic surgery has the potential to offer an effective therapeutic option for comatose patients with large supratentorial intracerebral hemorrhages, matching conventional craniotomy for emergent treatment in terms of mortality and management of ICP.  相似文献   
40.
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