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991.
We examined the role of vagus nerves in the transmission of the portal glucose signal in conscious dogs. At time 0, somatostatin infusion was started along with intraportal insulin and glucagon at 4-fold basal and basal rates, respectively. Glucose was infused via a peripheral vein to create hyperglycemia ( approximately 2 fold basal). At t = 90, hollow coils around the vagus nerves were perfused with -10 degrees C or 37 degrees C solution in the vagally cooled (COOL) and sham-cooled (SHAM) groups, respectively (n = 6 per group). Effectiveness of vagal blockade was demonstrated by increase in heart rate during perfusion in the COOL vs SHAM groups (183 +/- 3 vs 102 +/- 5 beats per minute, respectively) and by prolapse of the third eyelid in the COOL group. Arterial plasma insulin (22 +/- 2 and 24 +/- 3 micro U/mL) and glucagon (37 +/- 5 and 40 +/- 4 pg/mL) concentrations did not change significantly between the first experimental period and the coil perfusion period in either the SHAM or COOL group, respectively. The hepatic glucose load throughout the entire experiment was 46 +/- 1 and 50 +/- 2 mg . kg(-1) . min(-1) in the SHAM and COOL groups, respectively. Net hepatic glucose uptake (NHGU) did not differ in the SHAM and COOL groups before (2.2 +/- 0.5 and 2.9 +/- 0.8 mg . kg(-1) . min(-1), respectively) or during the cooling period (3.0 +/- 0.5 and 3.4 +/- 0.6 mg . kg(-1) . min(-1), respectively). Likewise, net hepatic glucose fractional extraction and nonhepatic glucose uptake and clearance were not different between groups during coil perfusion. Interruption of vagal signaling in the presence of hyperinsulinemia and hyperglycemia resulting from peripheral glucose infusion did not affect NHGU, further supporting our previous suggestion that vagal input to the liver is not a primary determinant of NHGU.  相似文献   
992.
Using a very simple flow cytometry protocol, we found that CD36 and CD117 on granulocytes and CD56 on monocytes were the major bone marrow phenotypic aberrations in patients with myelodysplasia, including CMML. CD56 on monocytes was associated with CMML. Importantly, phenotypic aberrations were lost on blood cells, except for CD56.  相似文献   
993.
994.
Hemophagocytosis is defined by a systemic macrophages activation, phagocyting the blood elements. This syndrome can be primary or secondary to multiple causes such as neoplasia or infections. We report here the first case of a hemophagocytosis caused by an Escherichia coli infection of ascitis fluid.  相似文献   
995.
We report the case of a 75-year-old woman with liver metastases of a urothelial carcinoma accompanied by a marked increased in CA 19-9 serum level. The mechanisms leading to this elevation, similar to that observed in biliary tract diseases, are discussed.  相似文献   
996.
997.
BACKGROUND: In the past two decades, cases involving patients requiring cardiac surgery have become more complex, presenting with more comorbidities. Outcome analysis has become very important in assessing the quality of cardiac surgical care in these patients. The latest version of the Parsonnet scoring system was developed in 2000 and is the most recent system available. OBJECTIVE: To evaluate the accuracy of the Parsonnet scoring system in a major Canadian university-based cardiac surgery centre with a population of high-risk patients. METHODS: Data on 4883 consecutive patients operated on between 2000 and 2005 were prospectively collected, and a standardized mortality rate was calculated using the Parsonnet score as the ratio of observed deaths to expected deaths. Analyses were conducted on the whole group and on subgroups, based on Parsonnet score distribution quantiles, age and surgery status. RESULTS: The mean Parsonnet score was 18.8+/-13.7 (range 0 to 83). The overall mortality rate was 6.4%. The overall standardized mortality ratio was 0.52 (95% CI 0.420 to 0.568), which was statistically significant (P=0.01). The observed mortality rate was significantly lower than expected in all categories. CONCLUSIONS: Despite more complex cases with multiple comorbidities, the results of cardiac surgery in a Canadian university hospital show better results than expected when using the Parsonnet score.  相似文献   
998.
999.
Many of our daily activities rely on a brain system called working memory, which implements our ability to encode information for short-term maintenance, possible manipulation, and retrieval. A recent intracranial study of patients performing a paradigmatic working memory task revealed that the maintenance of information involves a distributed network of oscillations in the gamma band (>40 Hz). Using a similar task, we focused on the encoding stage and targeted a process referred to as short-term consolidation, which corresponds to the encoding of novel items in working memory. The paradigm was designed to manipulate the subjects' intention to encode: series of 10 letters were presented, among which only five had to be remembered, as indicated by visual cues preceding or following each letter. During this task we recorded the intracerebral EEG of nine epileptic patients implanted in mesiotemporal structures, perisylvian regions, and prefrontal areas and used time-frequency analysis to search for neural activities simultaneous with the encoding of the letters into working memory. We found such activities in the form of increases of gamma band activity in a set of regions associated with the phonological loop, including the Broca area and the auditory cortex, and in the prefrontal cortex, the pre- and postcentral gyri, the hippocampus, and the fusiform gyrus.  相似文献   
1000.
A 32-year-old man presented with asthenia, weight loss, cough, and dysphagia following a recent stay in Morocco. Endoscopy showed a bulky mass of the epiglottis suspected of being a malignant tumor. The patient underwent jointly an F-18 FDG PET/CT and a biopsy of the tumor. Against all expectations, biopsy revealed granulomatous inflammation with epitheloid giant cells and caeseating necrosis. These findings associated with the presence of acid-fast bacilli in the sputum smears were highly suggestive of laryngeal tuberculosis, which was confirmed later after cultivation of mycobacteria. F-18 FDG PET showed diffuse pharyngolaryngeal and lung uptake with bilateral cervical and abdominal nodes, but also one thoracic vertebral uptake. Lung CT could have revealed carcinomatous dissemination, but cavitary lesions in some pulmonary segments were more evocative of tuberculosis. Moreover, cerebral MRI showed brain tuberculomas not visualized on F-18 FDG PET/CT. The patient was treated with a 5-antituberculosis drug regimen, which improved clinical symptoms with epiglottis mass regression, and lung CT image reduction, clinching the systemic tuberculosis diagnosis. A control F-18 FDG PET/CT performed 5 months later showed disappearance of the pharyngolaryngeal and node uptake, with an improvement of lung uptake without normalization, arguing for persistent disease. Unexpected pathologic findings may be present in more than 3% of neck dissections. Although this is usually indolent, with the underlying SCC remaining the main prognostic determinate, it may significantly complicate postoperative management.  相似文献   
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