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71.
The aim of this research was to quantify the number of corpora amylacea and lipofuscin-bearing neurons in the parahippocampal region of the brain. Right parahippocampal gyrus specimens of 30 cadavers were used as material for histological and morphometric analyses. A combined Alcian Blue and Periodic Acid-Schiff technique was used for identification and quantification of corpora amylacea and lipofuscin-bearing neurons. Immunohistochemistry was performed using S100 polyclonal, neuron-specific enolase and glial fibrillary acidic protein monoclonal antibodies for differentiation of corpora amylacea and other spherical inclusions of the aging brain. Cluster analysis of obtained data showed the presence of three age groups (median age: I = 41.5, II = 68, III = 71.5). The second group was characterized by a significantly higher numerical density of subcortical corpora amylacea and number of lipofuscin-bearing neurons than other two groups. Values of the latter cited parameters in the third group were insignificantly higher than the first younger group. Linear regression showed that number of parahippocampal lipofuscin-bearing neurons significantly predicts numerical density of subcortical corpora amylacea. The above results suggest that more numerous parahippocampal region corpora amylacea and lipofuscin-bearing neurons in some older cases might represent signs of its’ neurons quantitatively-altered metabolism.  相似文献   
72.
Peripheral nerve disorders may be classified into compressive or entrapment neuropathies and non‐compressive neuropathies. Muscle denervation recognized on MRI may be a useful sign in the diagnosis of peripheral nerve disorders. Acute or subacute denervation results in prolonged T2 relaxation time, producing increased signal in skeletal muscle on short tau inversion‐recovery and fat‐suppressed T2‐weighted images. Chronic denervation produces fatty atrophy of skeletal muscles, resulting in increased muscle signal on T1‐weighted images. This review will outline and illustrate the various ways that muscle denervation as seen on MRI may assist in the diagnosis and localization of peripheral nerve disorders.  相似文献   
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BACKGROUND: Tumour necrosis factor-alpha (TNF-alpha) is an important regulator of the chronic inflammation contributing to tumour progression. Infliximab, an anti-TNF-alpha monoclonal antibody was investigated in this trial of patients with advanced cancer. The primary objectives were to determine the safety profile and biological response of infliximab in a cancer population. Clinical response was a secondary objective. PATIENTS AND METHODS: Forty-one patients received infliximab at 5 mg/kg (n = 21) or 10 mg/kg (n = 20) i.v. at 0 and 2 weeks and then every 4 weeks. Post-treatment samples were measured for changes in plasma and serum TNF-alpha, CCL2, IL-6 and C-reactive protein (CRP). RESULTS: Infliximab was well tolerated with no dose-limiting toxic effects. At both doses of infliximab, neutralisation of serum TNF-alpha was observed after 1 h while plasma CCL2, IL-6 and serum CRP were decreased 24 and 48 h following infliximab administration. Seven patients experienced disease stablisation (range 10-50+ weeks). There was no evidence of disease acceleration in any patient. CONCLUSIONS: Infliximab treatment was safe and well tolerated in patients with advanced cancer. There was evidence of biological activity with baseline TNF-alpha and CCL2 being correlated with infliximab response.  相似文献   
75.
BACKGROUND/AIMS: We investigated the effect of a somatostatin analogue (octreotide) on hepatic encephalopathy in a rat model. Fulminant hepatic failure was induced by thioacetamide twice daily for 3 consecutive days. METHODOLOGY: Animals with hepatic encephalopathy grade III were divided into 2 groups. The groups received saline (control) or octreotide. In both groups the distance traveled in the open field activity, neurological score and mortality time were evaluated before and after the treatment. RESULTS: In the control group the motor activity was 13.7 +/- 6.4 and 12.9 +/- 5.5 cm/10 min, the neurological score was 8.4 +/- 0.9 and 8.5 +/- 1.3 before and after the treatment, respectively. In the octreotide group the motor activity was 11.4 +/- 5.0 and 10.4 +/- 3.5 cm/10 min, the neurological score was 8.8 +/- 1.5 and 8.6 +/- 0.9 before and after the treatment, respectively. Mortality times in the saline and octreotide group were 76.1 +/- 28.1 and 89.7 +/- 46.5 min, respectively. All parameters of this study were statistically not significant. CONCLUSIONS: This study demonstrated that somatostatin analogue, octreotide does not effect hepatic encephalopathy in an experimental rat model.  相似文献   
76.
This randomized controlled trial was designed to answer the question: does administration of dexamethasone to neonates with bronchopulmonary dysplasia decrease the need for assisted ventilation? Twenty-five infants with a birth weight < 1501 g, requiring mechanical ventilation and FiO2 of ± 0.30 at 21-35 days of age, were randomized to treatment with iv dexamethasone or to sham injections for 12 days. The primary outcome criterion was extubation within seven days after study entry. Treatment (n= 12) and control (n= 13) groups were well matched at entry. Dexamethasone facilitated weaning from assisted ventilation (p= 0.0154). There was no increased incidence of infection. Dexamethasone treatment resulted in a significant increase in glucosuria (p= 0.0002) and in systolic blood pressure (p= 0.0034). There was a significant decrease in heart rate (p= 0.0001) and a significant weight loss (p= 0.0002) following dexamethasone treatment. Dexamethasone treatment facilitated weaning from assisted ventilation but several systemic effects were noted that deserve further evaluation before dexamethasone becomes routine treatment.  相似文献   
77.
The effects of intermittent positive airway and continuous negative extrathoracic pressure ventilation on cerebral blood volume in preterm infants were studied using near infrared spectroscopy. In 12 infants continuous negative extrathoracic pressure caused a median decrease in cerebral blood volume of 0.14ml/100ml brain (95% confidence intervals (CI) 0.035–0.280) compared with no respiratory support. Oxygenated and deoxygenated haemoglobin also decreased, implying increased venous drainage as the main effect. In 17 infants intermittent positive pressure ventilation also caused a median reduction in cerebral blood volume of 0.06 ml/100 ml brain (95% CI 0.010–0.115) compared with endotracheal positive airway pressure. Deoxygenated haemoglobin increased by 0.07 ml/100 ml brain (95% CI 0.010–0.100) while oxygenated haemoglobin decreased by O.lOml/lOOml brain (95% CI 0.005–0.175). The increase in deoxygenated haemoglobin implies decreased venous drainage and the decrease in oxygenated haemoglobin implies that other factors may also be significant. Heart rate, blood pressure and oxygen saturation were monitored continuously and remained stable.  相似文献   
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Farczádi E  Kaszás I  Baki M  Szende B 《Neoplasma》2002,49(2):101-103
The short-term (7 days) effect of tamoxifen on apoptosis and mitosis index, p53, Bcl2 and Her-2/neu/c-erb2 expression in invasive ductal mammary carcinoma was studied histologically in the diagnostic biopsy and surgically removed tumor tissue of 10 patients. Following tamoxifen treatment expression of HER-2 and p53 decreased but Bcl2 remained unchanged. Mitotic activity decreased slightly, but not significantly. Apoptotic activity increased in six cases in the second sample compared to the values measured of the first biopsy. These changes may be attributed to the effect of antiestrogen therapy.  相似文献   
80.
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