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61.
We present and illustrate the MRI appearances of two children with choroid plexus carcinoma. The MRI characteristics of these rare tumours are reviewed. Since total surgical resection is a significant prognostic factor, early postoperative MRI was performed in both cases to ensure surgical clearance. In one case a complete resection was documented and this patient remains well at short-term follow-up. Residual tumour was noted in the second case, but despite "second look" surgery there was subsequent local relapse.  相似文献   
62.
The authors report two adult patients with chronic temporal lobe epilepsy and pathologic features consistent with Rasmussen's encephalitis. Although seizures persisted after temporal lobe surgery no progressive cognitive or neurologic deficit has emerged. Prominent auditory auras in each suggested a persisting epileptogenic focus in the superior temporal gyrus. The current findings expand the clinical spectrum of Rasmussen's encephalitis and suggest that chronic nonprogressive encephalitis may serve as the pathologic substrate of medically intractable temporal lobe epilepsy.  相似文献   
63.
OBJECTIVE: To compare and explore the skin manifestations of mitochondrial disorders in 14 children with puzzling and unexpected cutaneous presentations. STUDY DESIGN: One hundred forty children with mitochondrial disorders who had been under observation in our hospital for the last 10 years, were carefully examined by the same physicians. Skin and hair characteristics were investigated by the same dermatologist. All the children developed an early unexplained association of symptoms. Metabolic screening for abnormal oxidative-reduction in plasma and mitochondrial enzyme investigations confirmed the diagnosis of oxidative phosphorylation disorders. RESULTS: Fourteen children with mitochondrial disorders (10% of the original cohort) developed specific hair and skin abnormalities. Their cutaneous manifestations were similar, and could be classified into four categories: hair abnormalities, rashes and pigmentation disorders, hypertrichosis, and acrocyanosis. In 3 cases, skin disorders constituted the puzzling and unexpected manifestations of mitochondrial disease. Respiratory chain deficiencies in the cultured skin fibroblasts of 3 patients and heteroplasmic mitochondrial DNA rearrangement in the skin fibroblasts of 1 patient indicated that mitochondrial disorders may be expressed in the skin. CONCLUSION: Hair abnormalities and pigmented skin eruptions might belong to the broad spectrum of presenting symptoms of mitochondrial disease. The association of these dermatologic lesions with unrelated disorders should lead physicians to consider a diagnosis of mitochondriopathy as early as possible.  相似文献   
64.
Freshly prepared organ cultures of human placentae and amniotic membranes at term show different sensitivity to vesicular stomatitis virus (VSV) infection. In six of 16 amniotic membranes and seven of 17 placentae VSV replicated to relatively high titres (103–106TCID50/ml). The others were partially or completely resistant to virus infection (<101–102TCID50/ml). Addition of the immunomodulating agent, proline-rich-polypeptide (PRP) from ovine colostrum to explants freshly obtained from the organs, influenced VSV replication in a manner dependent on the innate immune state of the organ culture. In cultures resistant to the virus, PRP at a concentration of 10 μg/ml increased 10–10 000 times the VSV titre. In contrast, treatment of highly sensitive cultures by PRP hardly influenced viral replication at all. The effect of virus stimulation by PRP was abolished by specific anti-TNF antibodies. The results indicate that endogenous TNF may be one of the mediators of virus stimulation by PRP. Antibodies against TNFα, added to VSV infected organ cultures sensitive to the virus reduced viral replication. The antibodies caused stimulation of virus replication in VSV-infected resistant organ cultures. The results indicate the double role of endogenous TNF in viral replication in placenta and the amniotic membrane.  相似文献   
65.
Low gastric juice total vitamin C concentration in the presence of Helicobacter pylori infection probably plays a role in gastric carcinogenesis. Vitamin C plays a role in the neutralization of various pathogenic factors connected with H. pylori infection, including the destruction of free radicals, which damage tissues and cell DNA, and inhibition of the formation of N-nitroso compounds, which have a strong carcinogenic activity. The aim of the study was to determine whether tobacco smoking had any effect on gastric juice vitamin C concentration in healthy subjects and in patients infected with H. pylori. Eighty-six patients with dyspeptic symptoms undergoing routine endoscopy entered the study after giving informed consent. In all patients plasma and gastric juice total vitamin C levels were measured by a spectrophotometric method. They were entered into four groups: group I (controls) - H. pylori-negative non-smokers (n = 17), group II - H. pylori-negative smokers (n = 16), group III - non-smokers with H. pylori infection (n = 21), and group IV - H. pylori-infected smokers (n = 32). In the control group (I) the mean gastric juice total vitamin C concentration was 17.1 microg/ml (range 5.3-40.0 microg/ml), which was significantly higher (P < 0.05) than in group II (12.6 microg/ml, range 5.1-21.0 microg/ml), group III (5.8 microg/ml range 2.1-13.7 microg/ml) and group IV (3.9 microg/ml, range 1.1-10.6 microg/ml) (P < 0.001). Statistically significant differences also were noted between groups II and III (P < 0.01) and groups II and IV (P < 0.001) and between groups III and IV (P < 0.05). These results demonstrate that the concentration of vitamin C in gastric juice is significantly lower in smokers than in non-smokers. This was observed in healthy subjects as well as H. pylori-infected patients. This phenomenon may be one of the mechanisms whereby smoking contributes to the production of gastric lesions, impairs healing of peptic ulcers and also increases the recurrence rate of peptic ulcers in cases with H. pylori infection.  相似文献   
66.
This study of etoposide in thyroid cancer was designed to determine the activity and toxicity of etoposide in a variety of inoperable, thyroid hormone insensitive, and radio-iodine resistant primary cancers of the thyroid. The patients were required to have an ECOG performance status of at least 3 and no previous exposure to chemotherapy. The etoposide was given at a dose of 140 mg/m2 daily for 3 days and every 3 weeks until progression. The study was closed after 18 months because of poor accrual. There were no responses seen among the 10 patients accrued. The toxicity was primarily hematologic. There was no evidence of activity of etoposide in thyroid carcinoma, although this study lacked significant power because of the poor accrual.  相似文献   
67.
68.
OBJECTIVE: The aim of the study was to evaluate the course of twin pregnancy deliveries with particular regard to parity, the way of pregnancy termination, indications for cesarean section and sterility treatment. MATERIALS AND METHODS: The studied material consisted of two groups of patients who gave birth to twins in our clinic: the first one of 62 women in years 1997-2001 and the second group of 92 women in years 1987-1991. The average age of patients was 29.4 vs 28.7 respectively. RESULTS: There were 48.3% of primiparas in the first group, comparing to 44.5% in the second. The average time of pregnancy termination was 35 vs 35.97 Hbd respectively. Premature labours contributed to 80.6% vs 52% of all cases, which was statistically significant (p<0.001). Obstetrical procedures were applied in 6.5% vs 25% of cases respectively (p = 0.003). The indications for cesarean section have changed in regard to the position of the second fetus (when first in cephalic longitudinal lie, second in other than cephalic) and therefore contributed to 78.5% of cases in first and only 12.5% in second group. Thus the application of obstetrical procedures on the second fetus decreased to 18.2% vs 63% (p=0.002). In both groups cesarean sections were most often performed when the position of the first fetus was other than cephalic. In both groups the mediana of Apgar score of the second twin was lower than of the first. But the number of stillborns and general neonatal deaths significantly decreased over the years (0.8% and 2.4% vs 4.9% and 5.36%). Comparing both studied groups, the rate of the twin pregnancy after sterility treatment is rising: 16% vs 7.6%. CONCLUSIONS: The significance of the second twin position as an indication for cesarean delivery has risen over the years, thereby displacing the use of obstetrical procedures in those cases. In spite of earlier pregnancy termination and higher premature labour rate, there is a significant drop in the number of stillborns and neonatal deaths. In the age of infertility treatment, the number of twin pregnancy is rising.  相似文献   
69.
70.
Therapeutic doses of topiramate are not toxic to the developing rat brain   总被引:10,自引:0,他引:10  
Antiepileptic drugs (AEDs) used to treat seizures in pregnant women, infants, and young children may cause cognitive impairment. One of the implicated mechanisms is enhancement of apoptotic neuronal death, which occurs physiologically in the developing brain. We investigated whether topiramate, one of the newer antiepileptic drugs, has neurotoxic properties in the developing rat brain. Topiramate slightly but significantly enhanced apoptotic neuronal death in the 7-day-old rat brain at doses of 50 mg/kg and above. These doses are several folds higher than reported ED(50) doses in infant rodent seizure models that respond to topiramate. Electron microscopy confirmed that dying neurons following topiramate treatment displayed the same morphological features as neurons undergoing physiological cell death during development. When compared to the neurotoxicity profile of phenytoin, valproate, and phenobarbital, the separation between the effective anticonvulsant dose and the neurotoxic dose was greater for topiramate and the neurotoxic effect was lower.  相似文献   
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