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Central catecholaminergic activity was studied by measurement of norepinephrine (NE), epinephrine (EPI), their metabolites: total 3-methoxy-4-hydroxyphenylglycol (MHPG) and 3,4-dihydroxyphenylglycol in brain nuclei in response to bilateral dorsomedullary knife-cut (DMK-cut) in rats. In saline-pretreated conscious rats DMK-cut caused a marked hypertension, tachycardia and increases in plasma NE, EPI and vasopressin. Chlorisondamine (CHL) prevented the rise in plasma catecholamines and the tachycardia but failed to prevent the hypertension and the increment in plasma vasopressin. DMK-cut decreased NE and EPI in the nucleus tractus solitari (NTS) and A2 area; there were no catecholamine changes in A1 area or the periventricular nucleus but an increase in the paraventricular nucleus (PVN), the latter effect reversed by CHL, CHL alone or combined with DMK-cut had no effect on catecholamine concentrations in NTS-A2 area but lowered MHPG content. It is suggested that DMK-cut decreases the activity of the catecholaminergic system originating in A1 and terminating in PVN, where it causes catecholamine accumulation and may be involved in vasopressin release and thereby contribute to hypertension. In NTS-A2 area, however, the DMK-cut appears to increase catecholaminergic activity since catecholamines are depleted. Central effects of DMK-cut differ from those of ganglionic blockade-induced inhibition of the baroflex presumably due to sectioning of other pathways in addition to the primary baroreceptor input.  相似文献   
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OBJECTIVE: Our aim was to describe MRI and CT characteristics of primary lymphoma of bone during and after successful treatment. CONCLUSION: MRI showed a rapid decrease of tumor volume with complete disappearance of the soft-tissue component. Minor signal abnormalities of bone marrow without clinical relevance persisted for up to 2 years. CT showed bone remodeling within months with a persistent architecture similar to that of Paget's disease of the bone.  相似文献   
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BACKGROUND: We hypothesized that in patients with intracerebral tumours a subcortical metabolical shift may be present when the underlying pathology can, itself, be the epileptogenic focus. We also assumed that by studying the alterations in glucose metabolism beyond the tumour's borders we could identify a modulator area. METHODS: Sixty-seven patients with supratentorial brain tumour associated epilepsy were investigated interictally, in normoglycaemic conditions, by using [18F]fluorodeoxyglucose positron emission tomography (FDG PET). The studies were analysed semiquantitatively by calculating standardized uptake values and asymmetry indices. Normal subjects and patients with non-epileptic brain lesions were used as controls. RESULTS: Compared to normal controls frontal and temporal tumours showed significant changes in thalamic FDG uptake, which reflected hypometabolism of the affected side. It was noted in occipito-medial cortex in temporal tumours and in lentiform nucleus in frontal tumours as well. Comparison to lesional brains only proved that there was significant hypometabolism in lentiform nucleus in temporal tumours. CONCLUSIONS: The quantified values obviously reflect biological changes. The observed subcortical hypometabolism is most likely secondary to underlying pathology. Although seizures in tumorous patients do not originate from subcortical structures their influence on cortical sites of seizure initiation could be explained by defective subcortical regulation of cortical excitability.  相似文献   
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Bende J  Ursu M  Csiszar M 《Obesity surgery》2004,14(2):236-238
Background: Laparoscopic adjustable gastric banding (LAGB) was started in Hungary in 1998. We used Lap-Band and SAGB devices. In this study we present our experience through the learning curve. Methods: From Jan 1999 to Dec 2002, 54 patients underwent laparoscopic surgery for morbid obesity in our department, using the Lap-Band? and SAGB. There were 33 men and 21 women, with median age 42 (range 20-64), and preoperative BMI 50 kg/m2 (range 41-66). All underwent LAGB, except one patient who had laparoscopic vertical banded gastroplasty.The procedures used the 4-trocar technique. Results: The first patient required reoperation because of gastric rupture from drinking sparkling mineral water despite of our advice. Excluding this, we had no intraoperative or short-term postoperative complications. Mean operating time was 82 minutes (range 55-192), and hospital stay was 3 days. Followup ranges from 1 to 36 months. Mean weight loss was 47 kg at 12 months and 67 kg at 36 months. Mean BMI fell to 29 kg/m2. Conclusion:With its safety and effectiveness, LAGB has been a good choice for handling morbidly obese patients in our early experience.  相似文献   
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OBJECTIVE: To first report the successful use of the new inodilator levosimendan in a premature infant with congestive heart failure (CHF) following cardiac surgery. Although the calcium sensitizer levosimendan improves hemodynamics in adults with CHF, no data are available on the use of levosimendan in premature infants with CHF. DESIGN: Single case report. SETTING: Twenty-bed postoperative adult and pediatric cardiac intensive care unit. PATIENT: A 32 wks gestational age, 1525-g premature male twin with transposition of the great arteries. INTERVENTIONS: The patient underwent arterial switch operation. MEASUREMENTS AND MAIN RESULTS: Immediately after operation, the patient developed signs of low cardiac output syndrome. Mixed venous saturation was 56%, serum lactate increased to 14.8 mmol/L, systolic arterial pressure was 40 mm Hg, left atrial pressure was 24 mm Hg, and echocardiography showed reduced left ventricular function with a fractional shortening of 10%. There were no signs of reduced coronary perfusion. Milrinone, dobutamine, and epinephrine did not improve hemodynamics. Levosimendan was initiated at a dose of 0.05 mug.kg.min, increased to 0.1 mug.kg.min, and continuously infused for 24 hrs. Within 6 hrs after starting the levosimendan infusion, left atrial pressure decreased to 7 mm Hg and systolic arterial pressure increased to 60 mm Hg; within 24 hrs after initiation serum lactate level normalized to 1.7 mmol/L and mixed venous saturation increased to 81%. Echocardiography revealed improvement of left ventricular function with a fractional shortening of 25%. No side effects were recognized during administration of levosimendan. CONCLUSIONS: In this premature neonate with postoperative low cardiac output syndrome due to failing myocardial function, levosimendan was a potent inotropic agent.  相似文献   
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