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1.
Cytochemical analysis of leukemic blasts from 46 patients with acute myeloblastic M2 leukemia (according to the FAB classification) was performed before and after cytostatic therapy, and compared with findings obtained in 20 age- and sex-matched control subjects. Cytochemical findings for myeloperoxidase (MPO), Sudan black B, acid phosphatase and alpha-naphthyl-acetate esterase (ANAE) were related to the achievement of the first complete remission (CR),i.e. data were compared after the patients had been divided into CR and non-CR groups. The analysis clearly showed that a high proportion of myeloperoxidase- and, to a lesser extent, Sudan black B-positive blasts before treatment may have constituted a significantly unfavourable prognostic factor.  相似文献   
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Honeybee venom hyaluronidase (Api m 2) is a major glycoprotein allergen. Previous studies have indicated that recombinant Api m 2 expressed in insect cells has enzyme activity and IgE binding comparable with that of native Api m 2. In contrast, Api m 2 expressed in Escherichia coli does not. In this study, we characterized the carbohydrate side chains of Api m 2 expressed in insect cells, and compared our data with the established carbohydrate structure of native Api m 2. We assessed both the monosaccharide and the oligosaccharide content of recombinant Api m 2 using fluorophore-assisted carbohydrate electrophoresis and HPLC. To identify the amino acid residues at which glycosylation occurs, we digested recombinant Api m 2 with endoproteinase Glu-C and identified the fragments that contained carbohydrate by specific staining. Recombinant Api m 2 expressed in insect cells contains N-acetylglucosamine, mannose, and fucose, as well as trace amounts of glucose and galactose, and the oligosaccharide analysis is consistent with heterogeneous oligosaccharide chains consisting of two to seven monosaccharides. No sialic acid or N-acetylgalactosamine were detected. These results are similar to published data for native Api m 2, although some monosaccharide components appear to be absent in the recombinant protein. Analysis of proteolytic digests indicates that of the four candidate N-glycosylation sites, carbohydrate chains are attached at asparagines 115 and 263. Recombinant Api m 2 expressed in insect cells has enzymic activity and IgE binding comparable with the native protein, and its carbohydrate composition is very similar.  相似文献   
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The antibiotic 5-nitrofurantoin (5-NF) has been used widely for the treatment of urosepsis in children during the last 20 years. Recent experimentation suggests the need for reevaluating its genotoxic potential. Because of possible differences in the metabolism and clearance of 5-NF in young and adult animals, we conducted a study to determine whether micronuclei caused by 5-NF were age-related. The in vivo micronucleus (MN) assay was performed on 3- and 8-week-old mice given single intraperitoneal injections of 5, 10, and 50 mg/kg 5-NF. Blood samples from the tail vein were taken before injection (baseline) and at 48, 96, 168, and 336 hr (2 weeks) after the treatment. One thousand reticulocytes were analyzed for micronuclei from each animal. Compared to similar baseline values for young and adult mice, 5-NF caused a significant increase in MN frequency in both age groups. The mean MN frequency in the young animals was higher than in the adult animals for each dose and sampling time. MN frequencies remained significantly elevated in young animals even 2 weeks after exposure to 5-NF. The results of the study confirm the genotoxic potential of 5-NF in young and adult animals, and indicate that young animals are more sensitive to the genotoxic effects of 5-NF than adult mice and that the response in young mice persists for a significantly longer time. These findings may be related to poorly developed mechanisms of xenobiotic detoxification and renal elimination in young animals.  相似文献   
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Gastric diverticula are very rare and usually asymptomatic diseases. Clinical symptoms may include haemorrhage, mild discomfort and pain in upper abdomen. They are most frequently diagnosed incidentally during X-Ray examinations. In symptomatic diverticulum of gastric fundus was diagnosed roentgenographically and endoscopically and was successfully cured surgically.  相似文献   
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Syndromes of intracranial hemorrhage, and particularly subarachnoidal, i.e., intracerebral hemorrhage (SAH and IH) present clinical entities that are the most severe conditions in neurology. Timely recognition, diagnosis and adequate therapy are imperative. The most important factor that aggravates an already difficult prognosis of those entities is cerebral vasospasm. Upon the presented facts, the aim of this investigation was to establish the value and role of administration of selective calcium channel blocker--nimodipine in patients with SAH and IH compared to the degree of neurological and functional impairment, as well as the recovery of the function of consciousness compared to the patients with those syndromes from an earlier period, who were not treated with this medicament. Investigation comprised 30 patients who received nimodipine and 20 patients without this agent in therapeutic program. Results of the investigation confirmed significant difference concerning the neurological recovery, improvement of functional capability and recovery or consciousness disturbances, respectively, in patients who received nimodipine compared to the group without this agent. It can be concluded that nimodipine as calcium channel blocker with multitopic pharmacological effects on mechanism of SAH or IH development, respectively, as well as on the development of complications of those syndromes, particularly to the development of vasospasm and reactive ischemia, with the improvement of hemorrheologic disorders deserves to be included as the unavoidable segment of therapeutic program of SAH and IH syndrome immediately after clinical phenomenology is revealed.  相似文献   
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In Belgrade Military Medical Academy 88 males and 1 female (aged 13-55, average 28.6 years) with war craniocerebral injuries (CCI) were secondarily neurosurgically treated from October 1991 trough December 1992. Primary neurosurgical management of these patients was performed in war hospitals in former Yugoslavia. Out of 89 patients, 78 had penetrating, and 11 closed CCI. Out of 55 patients with penetrating CCI who underwent surgery, intracranial debridement was performed in 34 patients. All patients with severe CCI (GCS = 3-8) were severely by disabled or died, and in the majority of patients with minor CCI (GCS = 13-15) the outcome was good (p < 0.01). Statistical analysis showed no significant correlation between the extent of cerebral lesion and the outcome of penetrating CCI (p > 0.05). Eight (10.3%) patients with penetrating CCI died. The outcome of war CCI mostly depended on the severity of injury.  相似文献   
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OBJECTIVE: To assess the influence of acquired auditory control on some voice parameters in deaf children and adults after cochlear implantation. STUDY DESIGN: Prospective clinical study. SETTING: Tertiary referral center. PATIENTS: Twenty-nine prelingually deafened children and 11 postlingually deafened adults. INTERVENTIONS: The samples of a vowel /a/ were analyzed with an Multi-Dimensional Voice Program (Kay Elemetrics Corporation, Lincoln Park, NJ) before and 6 to 12 months after the cochlear implantation. MAIN OUTCOME MEASURES: The average fundamental frequency (F0), the short-term variation of F0 (JIT) and the amplitude (SH), the very long-term variation of F0 (vF0) and the amplitude (vAm), and the noise-to-harmonic ratio (NHR) were determined and compared for both age groups. The results of the acoustic analysis performed before the implantation were compared with the results after the implantation for children and adults. RESULTS: Significantly greater JIT, SH, vF0, and vAm were detected in the children than in the adults before and after the implantation. The prelingually deafened children significantly improved the control of their phonation after 6 to 12 months' use of the cochlear implant (JIT: p=0.014, SH: p=0.011, vF0: p=0.014, vAm: p=0.031). In the postlingually deafened adults, no significant improvement was found in any of the studied voice parameters after the implantation. F0 showed little or no change after the implantation in children and adults. CONCLUSION: As expected, the voice quality of the prelingually deafened children was significantly worse than that of the postlingually deafened adults. After cochlear implantation, the children significantly improved their short-term and long-term F0 and amplitude variability. In adults, no significant improvement was detected. We suppose that the improvement is a consequence not only of the acquired hearing control but also of the adaptation ability of neuromuscular phonation control and the maturing of these control mechanisms in children. In adults, better phonation quality in general and lesser improvement after the implantation can be the results of well-developed and stable phonation patterns.  相似文献   
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