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71.
BACKGROUND: There is a risk of viral hepatitis for children with cancer. Both hepatitis B virus (HBV) and hepatitis C virus (HCV) infections in countries with high prevalence cause major problems in the management of cancer patients. In this study, we evaluated the incidence and chronicity of HBV and HCV infections in children with malignant diseases receiving chemotherapy. PROCEDURE: One hundred ninety-eight children with cancer (mean age = 7.5 +/- 2.5 years) and 100 healthy children as a control group were screened for HBV and HCV. Liver function tests, the number of transfusions, HBV and HCV serology were regularly monitored. In seropositive children, HBV-DNA and HCV-RNA were measured. Chronic hepatitis was defined as having an alanine aminotransferase (ALT) level three times of upper normal limit, positive HBV and HCV antigenemia for longer than 6 months. Liver biopsies were performed in all children with chronic hepatitis. The relationship between the chronic hepatitis and study parameters was statistically analyzed. RESULTS: HBsAg positivity, anti-HCV, and mixed (HBV and HCV) infection were found in 11.6, 5.5, 2% of children, respectively. Most HBV infected children developed chronic hepatitis (48%) while 26 and 21.7% became carriers and immune, respectively. One died of acute fulminant HBV hepatitis. Of HCV infected children, 63.6% also had positive HCV-RNA. Four children with mixed infection (100%) all progressed to chronic hepatitis. In this setting, chronic hepatitis was observed in 22 of 38 infected children (57.8%). The majority had leukemia and lymphoma. Children with HBsAg antigenemia developed chronic hepatitis in shorter time than HCV positive children (median 13 months vs. 51 months, P < 0.001). CONCLUSION: We observed an increased incidence of chronic hepatitis and even mortality due to HBV infection. This suggests that HBV and HCV infections are serious causes of morbidity and mortality in children with cancer.  相似文献   
72.
While the effects of transient intestinal ischemia on mucosa have been well investigated, less is known about its effect on motor function. An experimental study was designed to investigate the effects of ischemia–reperfusion (I/R) on intestinal motility and intestinal muscular microcirculation. Wistar albino rats were divided into four groups: (1) baseline, (2) sham operation, (3) I/R, and (4) I/R with allopurinol pretreatment. Ischemia was induced by clamping the superior mesenteric artery (SMA) for 10 min. Gastroanal transit time (GATT) was measured with serial x-rays after instillation of barium sulfate to the stomach. Intestinal muscular microcirculation was evaluated by determining the number of carbon-perfused intestinal muscular microvessels (CPIMM). I/R prolonged GATT and decreased CPIMM significantly (P < 0.01). Pretreatment with allopurinol prevented prolongation of GATT and returned the number of CPIMM to the level of sham treatment (P < 0.01). In conclusion, reperfusion after 10 min of SMA ischemia alters intestinal motility. The no-reflow phenomenon plays an important role in this alteration of motility. Administration of allopurinol before reperfusion preserves intestinal motility by preventing the occurrence of no-reflow phenomenon.  相似文献   
73.
电针和氟西汀治疗抑郁症对血小板蛋白激酶C的影响   总被引:7,自引:0,他引:7  
目的:通过对不同治疗前后抑郁症患者血小板蛋白激酶C(PKC)含量的测定,研究细胞信号传导系统在抑郁症的变化和不同治疗对信号传导的影响.方法:临床采用双盲对照设计,选取符合DSM -IV抑郁症(MDD)和ICD-10抑郁症(MDD)诊断标准的抑郁症患者,随机分入三个治疗组:电针组20例,氟西汀组21例,针刺对照组21例.疗程6周.30名年龄和性别匹配的健康志愿者作为正常对照.在治疗前后各提取血小板,并分离血小板膜和血小板质,用免疫沉淀、放射自显影等方法测定血小板膜和血小板质中不同PKC亚型的蛋白含量.结果:抑郁症患者血小板膜和血小板质PKC的含量均有降低.氟西汀治疗后经典PKC含量有进一步减少的趋势,非经典PKC和新PKC的含量则出现升高的趋势.电针和针刺治疗后经典PKC的含量呈升高的趋势,新PKC和非经典PKC的含量呈下降趋势.结论:结果提示抑郁症患者存在有磷脂酰肌醇信号传导通路的异常.电针和氟西汀对血小板膜和血小板质不同亚型的PKC含量变化的影响不同,提示电针治疗抑郁症的受体后机制不同于氟西汀.  相似文献   
74.
Introduction We report a case of unusual co-existence of multiple primary neoplasms of female genital tract. Case A 62-year-old gravida 2, para 2 was referred with spotting and vaginal discharge for about 6 months. Fractionate curettage was performed and documented endocervical squamous cell carcinoma in situ. Subsequently total abdominal hysterectomy and bilateral salphingo-oophorectomy was performed. Final pathological report demonstrated cervical squamous cell carcinoma, right ovarian Brenner tumor, left ovarian granulosa tumor and endometrial polyps. Discussion Multiple primary neoplasms of female genital tract is a well-recognized yet rare occurrence. Although the presented case is probably an incidental event, the pathogenesis of the neoplastic process affecting the tissues with different embryological origin needs further research and evaluation. It is important to distinguish multiple primary neoplasms from metastatic disease because of the fact that overall survival as well as treatment would vary considerably.  相似文献   
75.
 During the last decade, several publications have appeared associating the maternal use of cocaine and subsequent development of necrotizing enterocolitis (NEC). In 1994, the effects of cocaine in pregnant rats had been reported by this group: a significant decrease in the number of live births, mean birth weight and mean placental weight. In addition, histopathologic examinations revealed severe inflammation and degenerative vascular changes in the uterus and placenta. Severe histopathologic changes resembling NEC such as focal necrosis, necrobiosis, and hemorrhagic inflammatory changes in the gastrointestinal tract of the embryos were also reported. The aim of the second part of this study was to assess the hemodynamic effects of cocaine HCl in pregnant rats and the results of perfusion studies in the uterus, placenta, and fetuses to determine a relation between the dose of drug, hemodynamic changes, and degree of histopathologic findings. Forty-seven Wistar albino rats and 91 rat fetuses were studied: group A (pregnant rats), 16 rats and 91 rat fetuses, group B (non-pregnant rats), 31 rats. Each group was divided into subgroups of cocaine-abused and non-cocaine-abused rats. In each group 2–3 mCi technetium Tc-99m methoxyisobutyl-isonitryl (Sesta MIBI) was injected into the tail vein. Radioactivity counts per g tissue (cps/g) in the uterus, placenta, and fetus were assessed by gamma counter. Cocaine 75 mg/kg per day severely decreased the perfusion of the uterus, placenta, and fetuses. These impairments were statistically significant. In lower doses (30–50 mg/kg per day) no statistically significant changes were observed in the perfusion of the uterus and placenta, but a significant decrease in fetal perfusion was seen. In group B, no significant changes in the perfusion of the uterus due to cocaine were seen. Thus, maternal cocaine abuse results in a reduction in perfusion of the uterus, placenta, and fetus. There was a dose-dependent correlation between the perfusion changes and the development of NEC-like histopathologic changes: the higher the cocaine dose received by the mother, the higher the level of placental and fetal injury. We suggest that perinatal cocaine exposure should be considered a high risk for development of NEC in rat fetuses and embryos. For this reason, infants with a history of possible maternal cocaine abuse or positive urinary cocaine metabolites have to be followed very carefully for NEC. Accepted: 13 December 1999  相似文献   
76.
Pulmonary large cell carcinoma with rhabdoid phenotype   总被引:1,自引:0,他引:1  
Large cell carcinoma of the lung with a rhabdoid phenotype is very rare. We present a 55-year-old man with multiple nodules in his lung. He had an emergency operation because of abundant hemoptysis. The microscopic appearance was a large cell carcinoma with a pure rhabdoid phenotype. There were no foci of any other carcinomatous components. Tumor cells had abundant eosinophilic cytoplasmic globules and eccentric nuclei and did not adhere to each other. Histochemically, these cells were periodic acid-Schiff-negative. Immunohistochemically, vimentin and neuron-specific enolase were positive. Epithelial membrane antigen was focally and weakly positive, p53 was positive in 60% of tumoral cells, and Ki-67 (MIB-1 labeling index) was 50%. The patient died of disseminated disease 2 months after the operation.  相似文献   
77.
78.
Reubel GH  Beaton S  Venables D  Pekin J  Wright J  French N  Hardy CM 《Vaccine》2005,23(35):4417-4426
The antifertility potential of zona pellucida proteins was tested in European red foxes by immunizing females with recombinant vaccinia viruses that express zona pellucida subunit C proteins. The fox zona pellucida C (fZPC) protein was newly identified and isolated as a cDNA clone from fox ovary RNA. Eighteen European foxes were inoculated with the recombinant vaccinia viruses or with wildtype vaccinia virus (wtVV) and their clinical, virological and immune responses evaluated. Following intradermal inoculation with wtVV or recombinant vaccinia virus expressing fox zona pellucida C (rVV-fZPC), or after peroral administration with recombinant vaccinia virus expressing the porcine zona pellucida C protein (rVV-pZPC) clinical signs of disease were not observed. Five out of six foxes developed antibodies to wtVV proteins. However, none of 12 foxes (six inoculated intradermally with rVV-fZPC, six perorally with rVV-pZPC) reacted in immunoblots with the transgenic fZPC or pZPC, respectively. Infectious wtVV, rVV-fZPC or rVV-pZPC was not isolated from mucosal secretions of any of the foxes whereas viral DNA was present in oral swabs of 3/18 foxes as determined by PCR. Hematological parameters remained mostly unchanged. Histopathological changes were not observed in the ovaries of rVV-fZPC or wtVV inoculated foxes. The data indicate that inoculation of foxes with cell culture infectious wtVV, rVV-fZPC or rVV-pZPC did not result in production of infectious progeny virus in vivo. For this reason transgene expression may have been insufficient to induce adequate immune responses against the transgenic proteins.  相似文献   
79.
A 33-year-old pregnant woman of 38 weeks' gestation with massive peritoneal ascites presented. A cesarean section was performed and a viable 3.100 g male infant was delivered. Biopsy of the nodular enlargements from the omentum revealed a malignant epithelial peritoneal mesothelioma. Malignant mesothelioma is a rare malignancy which has not been described in term pregnancy and appears to be unaffected by the pregnant state.  相似文献   
80.
Role of free radicals and antioxidants in nasal polyps   总被引:3,自引:0,他引:3  
OBJECTIVES/HYPOTHESIS: The aim of this study is to determine the role of free radicals and antioxidants in nasal polyps. STUDY DESIGN: Prospective, randomized, controlled study. METHODS: Thirty-one patients with nasal polyposis and a control group consisting of 19 patients with septal deviation and lower turbinate hypertrophy were included in the study. Levels of the antioxidants retinol, beta-carotene, alpha-tocopherol, and ascorbic acid were measured from the sera of the patients with nasal polyposis and the control group. Plasma levels of superoxide dismutase activity (SOD), glutathione peroxidase (GSHPX) activity, and reduced glutathione (GSH) were also obtained. As a peroxidation product, the levels of the malondialdehyde-thiobarbituric acid (MDA) combination were measured from the plasma of patient and control groups. Measurements of MDA, GSH, and alpha-tocopherol levels were also taken from the polyp tissue and turbinate mucosa of the control group. RESULTS: The blood levels of antioxidants and MDA as an oxidant were significantly different in the patient group compared with the control group (P <.01). The tissue levels of antioxidants and MDA were significantly different in the patients with polyposis compared with the control group (P <.01). The blood and tissue anti-oxidant levels were found to be decreased, and MDA levels as an oxidant increased significantly in the patient group with polyposis when compared with the control group, and there was a negative correlation between oxidative stress and antioxidants. CONCLUSION: This study demonstrates that oxidative stress and tissue and blood antioxidants in the patients with polyposis were significantly different compared with the control group. The blood and tissue antioxidant levels decreased, and MDA levels, as an oxidant, increased significantly in the patient group with polyposis when compared with the control group. The current study demonstrates that there is strong evidence related to oxidative stress in the pathogenesis of nasal polyposis, and antioxidants can have a preventive role in free-radical-mediated tissue damage in nasal polyposis.  相似文献   
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