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71.
BACKGROUND/PURPOSE: Preventing thrombus formation after caustic esophageal ingestion has been proposed to have beneficial effects. Therefore, an experimental study was carried out to investigate the effects of heparin on the esophagus after caustic burns. METHODS: Caustic esophageal burns were produced in rats by irrigation with 50% NaOH as described by Liu. Rats were divided into four groups as follows: group A, animals with esophageal burns, received placebo and underwent autopsy 48 hours after caustic injury; group B, animals with esophageal burns, received subcutaneous heparin treatment and underwent autopsy 48 hours after caustic injury; group C, animals with esophageal burns, received placebo and underwent autopsy 28 days after caustic injury; group D, animals with esophageal burns, received subcutaneous heparin treatment for 7 days and underwent autopsy 28 days after caustic injury. Histopathologic evaluation was performed in all groups, and collagen content of esophageal sections was analyzed by determination of hydroxyproline levels. RESULTS: Submucosal vascular thrombosis was encountered in all group A animals but the submucosal venules and arterioles were patent in most of group B animals. Esophageal strictures did not develop in any of group D animals, although varying degree of esophageal stenoses were encountered in all animals of group C. The circumferences of the burned segment have been narrowed to 3+/-1 mm in group C rats. There was obvious collagen deposition in submucosa, and epithelial regeneration was not complete in group C rats. Submucosa and epithelial integrity seemed normal in group D animals. Hydroxyproline contents in group D were significantly lower compared with group C (P < .05). CONCLUSIONS: Heparin has ameliorating effects on stricture formation after caustic esophageal burn. Those effects may occur through possible anticoagulant, antithrombotic, and endothelial protective effects, and modifying effects of heparin on wound healing.  相似文献   
72.
Mumps is still a common childhood disease in rural areas where mumps vaccination is not widespread. A 14-year-old girl with fatal interstitial nephritis as a complication of mumps is reported. The patient had not been vaccinated with mumps vaccine and had contracted mumps during a village epidemic. The illness began with parotitis, and renal insufficiency developed within a week. The patient’s renal function rapidly deteriorated and the outcome was fatal. The postmortem renal necropsy sample demonstrated interstitial mononuclear cell infiltration, edema, and focal tubular epithelial cell damage, confirming the clinical diagnosis. In developing countries routine mumps vaccination may help to prevent possible fatal complications of mumps. Furthermore, patients with mumps, especially complicated cases, should be followed closely. Received: 19 August 1998 / Revised: 7 December 1998 / Accepted: 8 December 1998  相似文献   
73.
The effect of sex differences on event-related potentials in young adults.   总被引:3,自引:0,他引:3  
Female/male cognitive differences have been studied for some time; however, such differences in Turkish population is unknown. Evoked potentials (EPs) of the brain have been applied as an index of information processing in a wide variety of normal and cognitive impaired subjects. Scalp event-related potentials (ERP) evoked by auditory stimuli were recorded in 20 male and 18 female neurologically and audiologically normal young Turkish subjects of 18-25 years (Av. 20.6) of age. Standard auditory "Oddball" paradigm involving simple discrimination task of concentrating on infrequent (target) stimulus and ignoring frequent (non-target) stimulus was employed. EEG activity was recorded at the Fz, Cz, Pz and Oz electrode sites of the 10-20 system using Ag/AgCl electrodes. Wave forms were collected and averaged off-line by a Pentium 100 computer, which also controlled the stimulus presentation. In general, significant main effects of gender and electrode site on evoked potential components were found. The interpeak amplitudes N1-P2 and N2-P3 were higher in the male subjects than in the female subjects at Cz. N2-P3 were higher in the male subjects than in the female subjects at Oz. The latencies of N1, P2, N2, P3 components were not different between both sex. For both sexes we found that N1-P2 amplitude was higher at Fz and Cz than Pz and Oz. N2-P3 amplitude was higher at Fz than Oz for only female subject. In male subjects, latency of N2 was longer at Fz than Oz. There were no significant differences in the latencies of N1, P2, and P3 components between electrode sites in both sexes. We suggest that ERP components could be affected by sex, electrode site, and cognitive performance.  相似文献   
74.
Apoptosis in brain biopsies of subacute sclerosing panencephalitis patients   总被引:5,自引:0,他引:5  
Subacute sclerosing panencephalitis (SSPE) is associated with inflammatory infiltration, neuronal loss, and demyelination. The pathogenesis of these changes is unclear. We examined DNA fragmentation and Bcl-2 expression in brain biopsies of nineteen SSPE patients to investigate the role of apoptosis in tissue damage. DNA fragmentation was present in oligodendroglia, and, in tissues with neuronal loss, in neurons. Reactive astrocytes had no DNA fragmentation, but strong Bcl-2 expression. These results suggest apoptosis as one of the mechanisms for oligodendroglial and neuronal death in SSPE.  相似文献   
75.
3-Hydroxy-3-Methylglutaryl coenzyme A lyase (HMG-CoA) deficiency is a rare inborn error of leucine catabolism. The disease is characterized by recurrent episodes of metabolic acidosis, hyperammonemia without ketosis, hypoglycemia, lethargy, hepatomegaly, and seizures. This study has evaluated the magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) findings of three patients with HMG-CoA deficiency. The common findings on all of the MRI scans were multiple, coalescent, marked lesions in periventricular white matter and arcuate fibers, most prominently in frontal or periatrial regions that were superimposed on diffuse, slightly hyperintense subcortical white matter signal. Involvement of the caudate nucleus and the dentate nucleus were observed in the reported patients. MRS studies by both STEAM and PRESS spectra of all patients revealed a decrease in N-acetylaspartate and elevation in both myoinositol and choline. A pathologic peak at 1.33 ppm, which is compatible with lactate, and a particular peak at 2.42 ppm in all patients were also found. The combination of both MRI and MRS findings could be considered as being specific in patients with HMG-CoA lyase deficiency.  相似文献   
76.
77.
Medpor implants were placed on the periosteum of the mandible in infant rabbits to study their effects on growth. Three months later radiological and histopathological studies were performed in situ and after removal of the mandible. The authors demonstrate that implants did not affect normal development of the mandible; however, there was a decrease in bone thickness and a mononuclear cell reaction was caused where the implant came in contact with the bone.  相似文献   
78.
Thermal injury of the genitalia usually occurs as part of larger body surface burns. The most common sequelae of burns of the penoscrotal region are contractures of penile shaft, but we did not encounter any reported cases in English Literature with cryptorchidism as a sequel of burn injury. A 7 year old boy with cryptorchidism as a component of extensive perineal and inguinal burn deformity is reported to indicate the role of burn injury in cryptorchidism. Cryptorchidism as a component of perineal burn injury may be caused by the attachment of the cremaster muscle or fascia to the abdominal wall during the process of wound healing. As healing process of wounds on inguinal region by contraction may cause testis entrapment and cryptorchidism, a careful genital examination bears a great importance in inguinal burn deformities in order not to miss any trapped testis and replace it as early as possible before degenerative changes begin.  相似文献   
79.
Fluorescein and indocyanine green videoangiography of choroidal melanomas   总被引:1,自引:0,他引:1  
PURPOSE: This study was performed to determine what role indocyanine green video angiography might play in the evaluation of choroidal melanomas, and to compare this role with that of fluorescein angiography. METHODS: Six patients with posterior segment uveal melanoma underwent digital fluorescein and indocyanine green videoangiography. All patients were women and their mean age was 50.7 years. RESULTS: In all eyes with melanoma, fluorescein angiography revealed irregular hyperfluorescence in the early phase and staining of the tumor in the late phase. A double circulation pattern was obvious in 1 eye with a mushroom-shaped melanoma. The patterns of indocyanine green videoangiography varied, depending on the degree of tumor pigmentation, thickness, and vascularity. Early frames of indocyanine green video angiography demonstrated hypofluorescence in all eyes, and the intrinsic choroidal vasculature was obvious in 3 eyes. In the late phase of indocyanine green videoangiograms, different patterns (hyperfluorescence, three-ring pattern) were observed. CONCLUSION: Indocyanine green videoangiography may be a useful adjunct to fluorescein angiography in the evaluation of choroidal melanomas.  相似文献   
80.
F Oztürk  E Kurt  U U Inan  L Emiro?lu  S S Ilker 《Cornea》1999,18(4):466-471
PURPOSE: To investigate the effects of topical acetylcholine and topical administration of propolis, a natural beehive product, on corneal epithelial wound healing. METHODS: The whole corneal epithelium was debrided in 42 eyes of 21 rats by mechanical scraping with a dulled scalpel blade. Animals were divided into three groups. Group 1 received topical 1% water extract of propolis (WEP), group 2 received topical acetylcholine (ACh), and group 3 (control group) received topical phosphate-buffered saline, 6 times a day for 3 days, starting immediately after debridement. The area of the corneal epithelial defect was stained with fluorescein, photographed, and then measured every 12 h. The mean epithelial defect area and the mean percentage of epithelial defect remaining at each follow-up were compared between the groups. RESULTS: The mean epithelial defect area and the mean percentage of epithelial defect remaining at each time were significantly smaller (p < 0.001, p < 0.05, respectively) in the ACh and propolis groups as compared with control groups. There was no statistically significant difference between the propolis or ACh groups at any time (p > 0.05). At 72 h, the mean percentage of defect remaining was 2.58% in the ACh group, 1.3% in the propolis-treated group, and 8.68% in the control group. CONCLUSIONS: This study demonstrated that ACh and propolis facilitated corneal epithelial wound healing of rats. Although the mechanisms of the effect of propolis on wound healing and its clinical use still remain to be determined, ACh may have a place in the treatment of corneal epithelial injuries.  相似文献   
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