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11.
Neuroimaging in Pineal Tumors   总被引:4,自引:0,他引:4  
F Reis  MD  AV Faria  MD  PhD  VA Zanardi  MD  PhD  JR Menezes  MD  F Cendes  MD  PhD  LS Queiroz  MD  PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread.  相似文献   
12.
Summary The RPS5 gene has been characterised through its ability to reduce invertase production by the SUC5 gene. In this paper we show that RPS5 acts by maintaining low levels of SUC5 mRNA. We also show that RPS5 acts on the SUC1 and SUC4 genes but not on SUC2 and SUC3, which are members of the SUC family. RPS5 also shows a pleiotropic effect on the amount of mitochondrial cytochromes.  相似文献   
13.
The relationship between maternal age and cesarean section in low-risk nulliparas was analysed in 7454 perinatal clinical records selected from eleven databases of Latin American institutions obtained with a comprehensive perinatal information system. The risk of cesarean section in nulliparas between 29 and 49 years of age was found to be three times higher than that corresponding to pregnant women of lesser age. This clearly more aggressive obstetrical conduct could not be explained by the main indications for cesarean section.  相似文献   
14.
Abdominal abnormalities in AIDS: detection at US in a large population   总被引:1,自引:0,他引:1  
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15.
Gastroesophageal reflux disease (GERD) is the most common disease of the upper gastrointestinal tract. With the introduction of proton pump inhibitors medical treatment of GERD has been significantly improved. However, the development of laparoscopic antireflux surgery resulted in an increasing interest of surgeons in this disease. An interactive meeting was organized in order to develop an agreement between gastoenterologists and surgeons regarding therapeutic decisions and this is the main topic of this paper.  相似文献   
16.
Effect of cyclosporin a on proteinuria in patients with Alport's syndrome   总被引:1,自引:0,他引:1  
Eight patients with Alport's syndrome and massive proteinuria (129±60.57 mg/m2 per hour) were treated with cyclosporin A (CyA) for 8 months. The average dose of CyA administered to all patients was 4.21±0.26 mg/kg per day and blood CyA levels of 63.4±4.1 ng/ml were attained. In five patients, proteinuria abated during the 3rd week of treatment. In the remaining three, all of whom had low creatinine clearance (82.0, 46.0 and 43.2 ml/min per 1.73 m2 respectively), proteinuria persisted but at levels lower than before treatment: 32.5±15.9 mg/m2 per hour versus 183.3±29.7 mg/m2 per hour. No permanent decrease in creatinine clearance was observed in any of these patients throughout treatment. In those patients in whom proteinuria abated, it reappeared 2 weeks after discontinuation of CyA treatment. We observed no significant increases in angiotensin II plasma levels in our patients during CyA administration. Although we have shown that CyA will reduce massive proteinuria in patients with Alport's syndrome, we cannot yet recommend its use as a therapeutic measure.  相似文献   
17.
The effect of acute and sequential volaemic changes on the gastroduodenal flow of saline was assessed in 23 anaesthetized dogs following two different experimental protocols. Hypervolaemia, by i. v. infusion of saline, induced a gradual decrease on gastroduodenal flow which amounted to 76% below control values (P < 0.001) when volaemic expansion attained 5% of body weight. This effect was volume dependent (17% increase on gastroduodenal flow per volume of infused saline equivalent to 0.5% of body weight, P < 0.001), lasted for at least 90 minutes after infusion was completed and was also obtained by expanding previously bled animals. Hypovolaemia due to bleeding was followed by an increase on gastroduodenal flow of about 88% above control values (P < 0.05) when haemorrhage was equal to 3% of body weight. This effect was also volume dependent (23 % increase on gastroduodenal flow per volume of blood shed equivalent to a 0.5% of body weight, P < 0.01) and was reversed after blood volume was restored. These modifications in the resistance of the gastroduodenal segment to the flow of liquid due to acute volaemic changes suggest that the extracellular fluid volume modulates the contractile activity of the gastroduodenal portion of the gut possibly to set a gastroduodenal handling of liquid adequate to cope with volaemic imbalances.  相似文献   
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The general public of the City of Bergen, Norway was Invitedto participate in a cholesterol screening programme in October1988. Participants received the results of the cholesterol screeningand nutritional information from trained health personnel. Ashort questionnaire was mailed to all 354 participants 1–2weeks after the initial cholesterol screening. In March 1990,all participants were invited to have their cholesterol levelsre-examined. Psychosocial factors believed to be predictiveof future serum cholesterol changes were assessed at baselinealong with demographic variables. The majority of participants(61%) reduced their cholesterol level from October 1988 to March1990, and the average reduction in cholesterol level for thetotal population was 4.0%. Baseline cholesterol levels, beingconfident of one's own ability to change one's diet (self-efficacy),seeing heart disease risk reduction as very important, and maritalstatus were factors that significantly predicted successfulcholesterol reduction 18 months later.  相似文献   
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