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101.
102.
Using functional MRI (fMRI) with concurrent EEG monitoring the authors studied cortical activation associated with epileptiform discharges in three patients with fixation-off sensitivity. The EEG paroxysmal activity elicited by eliminating central vision correlated significantly with an increased blood oxygen level-dependent signal in the extrastriate cortex (Brodmann areas 19 and 37). fMRI provides a unique opportunity for localizing precisely the cortical areas generating paroxysmal activity in patients with fixation-off sensitivity.  相似文献   
103.
Anterior rectal resection with total mesorectal excision is currently regarded as the operation of choice in patients with neoplasms of the extraperitoneal rectum. This operation is associated with a significant incidence of anastomotic dehiscence. Some authors, therefore, advise the execution of a protective stoma. From 1987 to 2000, 241 patients with rectal neoplasma were submitted to radical surgery: 183 to anterior rectal resection (extraperitoneal neoplasms in 129 cases and intraperitoneal neoplasms in 54) and 58 to a Miles operation. The total incidence of anastomotic complications was 8.1% (15 patients). In 12 cases (6.5%) a clinical dehiscence was observed, while in 3 patients (1.6%) an asymptomatic fistula was present. In the patients with symptomatic dehiscence a colostomy was performed in 5 cases (42%), while in 7 cases (58%) a conservative approach was adopted (total parenteral nutrition and antibiotic therapy), with complete healing of the fistula. The incidence of anastomotic complications was 9.3% in extraperitoneal neoplasms and 5.6% in intraperitoneal localizations. In relation to the anastomotic technique adopted, the incidence of dehiscences was 25% after 8 Knight-Griffen anastomoses, 16% after 12 manual anastomoses and 7.3% after 163 end-to-end mechanical anastomoses (P = NS). The percentage of anastomotic complications was greater in the period from 1995 to 1997, compared to the period from 1987 to 1994 (12.6% vs 3.8%, P = NS), due to the routine execution of rectal resection in conjunction with total mesorectal excision, particularly at the beginning of the experience, in 1995. In the last 36 cases from 1998 on the incidence of anastomotic complications was reduced to 8.3%, after the learning phase. No related mortality was observed. On the basis of our experience and the evidence reported in the international literature we do not think the execution of a protective stoma is justified after low and ultra-low colorectal anastomosis, except in selected cases.  相似文献   
104.
The attitudes and future decisions of teenage girls towards infant feeding methods, breast-feeding or bottle feeding have been investigated. A self-conducted questionnaire was completed by 146 secondary school girls ranging in age from 16 to 18 years. Economic convenience, better nutritional value, deeper emotional link with the infant, own and friends past experience nearly always in favour of breast-feeding, represent for the girls the main advantages of breast-feeding. On the other hand, many girls apprehend breast-feeding for various possible physical, psychological and social implications. Some aspects of the problem studied in this paper show a significant correlation with the future choice of infant feeding. The girls would be interested in receiving information at school. Suitable information during school health lessons may positively influence teenage girls to adopt breast-feeding as the infant feeding method of choice.  相似文献   
105.
We report a case of acute multiple sclerosis in whom computed tomography (CT) scan suggested the presence of a large plaque. The anatomical and functional recovery of the brain tissue was followed by means of repeated CT scan and 123I-HIPDM studies. Single photon emission CT may be successfully employed to monitor the pathophysiological changes associated with the demyelinating process.  相似文献   
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Airway epithelial cells are simultaneously exposed to and produce cytokines and reactive oxygen species (ROS) in inflammatory settings. The signaling events and the physiologic outcomes of exposure to these inflammatory mediators remain to be elucidated. Previously we demonstrated that in cultured mouse lung epithelial cells exposed to bolus administration of H(2)O(2), TNF-alpha-induced NF-kappaB activity was inhibited, whereas c-Jun-N-terminal kinase (JNK) activation was enhanced via a mechanism involving TNF receptor-1 (TNF-RI). In this study we used the nonphagocytic NADPH oxidase (Nox1) to study the effects of endogenously produced ROS on a line of mouse alveolar type II epithelial cells. Nox1 expression and activation inhibited TNF-alpha-induced inhibitor of kappaB kinase (IKK), and NF-kappaB while promoting JNK activation and cell death. Nox1-induced JNK activation and cell death were attenuated through expression of a dominant-negative TNF-RI construct, implicating a role for TNF-RI in Nox1 signaling. Furthermore, Nox1 used the TNF-RI adaptor protein TNF-receptor-associated factor-2 (TRAF2), and the redox-regulated JNK MAP3K, apoptosis signal kinase-1 (ASK1), to activate JNK. In addition, ASK1 siRNA attenuated both Nox1-induced JNK activity and cell death. Collectively, these studies suggest a mechanism by which ROS produced in lung epithelial cells activate JNK and cause cell death using TNF-RI and the TRAF2-ASK1 signaling axis.  相似文献   
109.
Silicon oxycarbide (SiOxCy) glass compositions are shown to exhibit a variable propensity to contact activate coagulation of whole human blood plasma that depends on X:Y surface stoichiometry. SiOxCy exhibit activation properties similar to pyrolytic carbon (PC) over a broad range of X:Y ratios. Surface composition of SiOxCy glass powders prepared by pyrolysis of thermosetting polysilsequioxanes roughly correlated with total carbon concentration of precursor resins and could be significantly modified by etching in alkaline solutions. Results suggest that SiOxCy may offer unique properties as a substitute for PC in medical-device applications demanding excellent tribological properties, such as artificial heart valves.  相似文献   
110.
Acetazolamide effects on cerebral blood flow in acute reversible ischemia   总被引:1,自引:0,他引:1  
Cerebral blood flow (CBF) was studied in 4 patients with acute reversible ischemia (RIND). To test the ischemic areas' vasoreactivity, CBF was measured by the Xenon-133 inhalation method, before and after acetazolamide injected intravenously. At the baseline CBF study, 3 patients presented hypoperfused areas while one patient had increased CBF over the affected hemisphere. The acetazolamide test, showed in this latter case a "steal phenomenon" while in the other 3 an increase of perfusion was evidenced, in areas of normal flow, as well as in areas with reduced flow. These results suggest that in the acute phase of patients with RIND, when brain regions of hypoperfusion and neurological signs are still present, the vasomotor response may be preserved.  相似文献   
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