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61.
BACKGROUND: The goals of this study included: (1) Identification of factors prognostic for event-free survival (EFS) and overall survival (OS), and (2) Definition of risk groups for risk adapted therapy in children with Hodgkin disease (HD). PROCEDURE: From 1991 to 2003, 69 children with newly diagnosed, untreated biopsy-proven stage I-IV HD were treated with chemotherapy (CT) and low-dose involved field radiotherapy (LD-IFRT). The relationship of pretreatment factors to EFS and OS was analyzed by univariate and multivariate analysis. RESULTS: The 5-year EFS and OS for all patients were 90.77% and 96.22%, respectively with a median follow-up of 73 months (3-137 months). Male to female ratio was 3:1 and 21 children (32.3%) were less than 7 years of age. Mixed cellularity was the predominant histologic subtype (38.5%). Factors associated with inferior EFS by univariate analysis were extranodal disease, hemoglobin level <11 g/dl, number of involved lymph node regions and stage. By multivariate analysis only stage IV disease was significant. CONCLUSION: Our study confirms that excellent results are achievable with combined modality therapy in childhood HD. In order to use risk-adapted therapy in children with HD, clinical prognostic factors should be validated with large, multicentered prospective clinical studies.  相似文献   
62.
An experimental study was planned to evaluate and compare the effects of orchidopexy and orchidectomy on the testes of rats subjected to unilateral abdominal testis with vas deferens obstruction. Four groups were established. Rats in the control group underwent a sham procedure. While the testis was maintained in the abdomen with the vas deferens ligated for 8 weeks in group 2, rats in groups 3 and 4 underwent orchidopexy or orchidectomy after 4 weeks. Remaining testes were harvested at the end of the 8-week period. Testis and body weights were obtained during harvest. Samples were evaluated through DNA flow cytometry, and percentages of haploid cells were determined. Groups were compared through unpaired t-test, and p-values less than 0.05 were considered significant. All three treatments had decreased testis weight over body weight values of ipsilateral testes. Ipsilateral orchidectomy increased the value among contralateral testes. However, none of the groups had a contralateral testicular value less than the sham-operated group. All three treatments decreased the percentage of haploid cells among ipsilateral testes, but only an abdominal testis was associated with a decrease in the percentage of haploid cells among contralateral testes. Maintaining a testis with an obstructed vas deferens in the abdomen for 8 weeks damages both ipsilateral and contralateral testes. Orchidopexy, while showing amelioration of the ipsilateral testis, spares the contralateral testis as well as orchidectomy. Orchidopexy for an undescended testis with vas deferens obstruction is a rational approach.  相似文献   
63.
Malignant fibrous histiocytoma is the most common type of soft tissue sarcoma in late adult life. The tumour may be seen rarely in burn scars and accompanying other kinds of malignancies. We herein report a case of a tumour that derived from an old burn scar on the scalp. The histological examination revealed that the tumour contained both malignant fibrous histiocytoma and squamous carcinoma areas. Malignant transformation in a burn scar is a well-known development; therefore, a new lesion occurring within the scar should not be neglected.  相似文献   
64.
In order to determine whether nicotine acts on corporal smooth muscle, the mechanism of its effect on strips of rabbit corpus cavernosum was studied in vitro. Rabbit corpus cavernosum muscle strips were mounted in an organ bath with modified Krebs-Henseleit solution and aerated with 95% O2 and 5% CO2. Tension was measured with isometric force transducers, and muscle relaxation was expressed as the percent decrease of precontraction induced by phenylephrine. Nicotine produced concentration dependent relaxation when preparations were precontracted by phenylephrine (10–5 M). The maximum nicotine-induced relaxation was 60.4±4.2% of the phenylephrine contraction and was not affected by indomethacin (10–5 M), Nw-nitro L-arginine methyl ester (3×10–5 M), methylene blue (10–5 M), glibenclamide (10–5 M), clotrimazole (10-6 M), tetraethylammonium (3×10–4 M), or 4-aminopyridine (10–3 M). Nicotine did not exhibit a calcium antagonizing effect. From these results, we conclude that nicotine-induced relaxation of the rabbit corpus cavernosum is not mediated by the release of nitric oxide, prostaglandins or a related substance, by the activation of potassium channels, or by the stimulation of nicotinic cholinoceptors. Further work is needed to determine the cellular mechanism(s) of the action by which nicotine acts on corporal smooth muscle.  相似文献   
65.
66.
Abstract Pulmonary artery involvement of hydatid disease caused by the Echinococcus granulosus parasite is an uncommon condition resulting from the opening of a visceral hydatid cyst into the venous circulation or the rupture of a cardiac hydatid cyst. We report a case of a 31-year-old woman with a hydatid cyst located in the right pulmonary artery. Clinical presentation was fatigue, cough, and dyspnea. Diagnosis was made by chest x-ray, computed tomography, and magnetic resonance imaging. The cyst was extracted under total circulatory arrest. Diagnosis and surgical therapy of the intraluminal pulmonary arterial hydatid cyst prevented possible occurrence of severe complications, such as cyst rupture, anaphylactic shock, and sudden death.  相似文献   
67.
The aim of this study was to compare the tocolytic effect of a selective cyclooxygenase-2 inhibitor, DFU (5,5-dimethyl-3(3-fluorophenyl)-4-(4-methylsulphonyl)phenyl-2(5H)-furanone), indomethacin and nimesulide on myometrial strips isolated from rats in both lipopolysaccharide-induced preterm labour and term labour. We also compared the constrictor effects of DFU and indomethacin on the fetal ductus arteriosus. Myometrial strips were obtained from preterm and term labour Wistar albino rats and were mounted in organ baths for the recording of isometric tension. DFU, nimesulide and indomethacin significantly inhibited KCl-, oxytocin-, prostaglandin E(2)- and prostaglandin F(2 alpha)-stimulated contractions of myometrial strips isolated from rats in preterm and term labour. The E(max) value of indomethacin was significantly lower than those for DFU and nimesulide (P<0.05), with no change-log (10) EC(50) values. There was no significant difference between in -log (10) EC(50) and E(max) values of DFU and nimesulide for any of the tissues (P>0.05). In addition, there was no significant difference between -log (10) EC(50) and E(max) values for each of these three agents in myometrial tissues isolated from rats in preterm and term labour (P>0.05). Fetal ductus arteriosus was significantly constricted by DFU (10 or 100 mg/kg) in preterm and term rats, although DFU (10 or 100 mg/kg)-induced constriction ratios were significantly lower than those for indomethacin (P<0.05). These data demonstrate that DFU, a specific cyclooxygenase-2 inhibitor, could be considered as a new therapeutic agent for preterm labour. However, careful attention should be given to constriction of the fetal ductus arteriosus.  相似文献   
68.
Schizophrenia is a complex disorder with a polygenic inheritance. Catechol-O-methyltransferase (COMT) plays a significant role in the regulation of dopaminergic systems. A polymorphism at COMT Val108/158Met has been identified in association with schizophrenia. We examined the allele and genotype association of the COMT Val108/158Met polymorphism of 297 unrelated schizophrenic patients who strictly met DSM-IV criteria for schizophrenia, and 341 healthy controls. We found significant difference in allele and genotype frequencies between schizophrenic patients and controls (chi2=13.030; P=0.001). The allele frequency of the COMT-L was 45.79% in the total schizophrenic patients, and 41.50% in controls. The genotype frequency of the COM-LL was 21.2% in the total schizophrenic patients, and 11.4% in controls (OR=2.085; 95% CI=1.350-3.219; chi2=11.293; P=0.001). With a separate sex analysis, the frequency of the COMT-L allele was moderately distributed in male schizophrenia (chi2=6.177; df=2; P=0.046). The COMT-LL genotype had a 1.818-fold increased risk for schizophrenia (OR=1.818; 95% CI=1.010-3.273; chi2=4.048; P=0.044). The frequency of the COMT-L allele was even more significantly distributed in women schizophrenia (chi2=7.797; df=2; P=0.020). The COMT-LL genotype had remarkably more increased risk for schizophrenia (OR=2.456; 95% CI=1.287-4.687; chi2=7.710; P=0.005). In conclusion, our results provide strong evidence for a role of the COMT-L allele and LL genotype in the etiopathophysiology of schizophrenia with a sexual difference.  相似文献   
69.
Bladder pheochromocytoma encountered on sonography   总被引:1,自引:0,他引:1  
Pheochromocytomas of the bladder are rare neoplasms, constituting < 0.06% of all vesical tumours. Common presenting features of this tumour include episodes of sweating, hypertension, haematuria and postmicturition syncope. We describe a case of bladder pheochromocytoma in a 66-year-old man whose only symptom of macroscopic haematuria was initially assessed with ultrasonography. Clinical presentation highlights the need for a high index of suspicion during sonographic evaluation of bladder neoplasms because such tumours might present without symptoms of adrenergic excess.  相似文献   
70.
There is currently substantial clinical interest in zinc (Zn) as a protective agent against radiation-related normal tissue injury. To further assess this drug's potential, the effect of Zn was studied in rats using a radiation-induced skin injury model. Sprague-Dawley rats were divided into four groups. Group 1 received neither Zn nor irradiation (control group). Group 2 received 30 Gy of gamma irradiation as a single dose to the right hind legs of the rats (RT Group). Groups 3 and 4 received the same irradiation plus 5 mg/kg/day Zn (RT+5 Zn group) or 10 mg/kg/day Zn orally (RT+10 Zn group), respectively. The rats were irradiated using a cobalt-60 teletherapy unit. Acute skin reactions were assessed every three days by two independent radiation oncology experts. At the endpoint of the study, light-microscopic findings were assessed by two independent expert pathology physicians. Clinically and histopathologically, irradiation increased dermatitis when compared with the control group (p < 0.05). The severity of radiodermatitis of the rats in the RT+5 Zn and RT+10 Zn groups was significantly lower than in the RT group (p < 0.05); radiodermatitis was seen earlier in the RT group than in the other groups (p < 0.05). Zn was found to be efficacious in preventing epidermal atrophy, dermal degeneration such as edema and collagen fiber loss, and hair follicle atrophy. The most protection for radiation dermatitis was observed in the RT+10 Zn group. It would be worthwhile studying the effects of zinc sulphate supplements in radiation-treated cancer patients, in the hope of reducing radiation-induced toxicity.  相似文献   
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