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91.
Eighteen professional divers (age range 24-33 yr, mean 28.3) participated in one simulated dive to 360 meters of seawater (msw) in a helium-oxygen (heliox) atmosphere with equal compression and decompression profiles. All divers were given an extensive neurologic examination before diving. Clinical neurologic symptoms observed during the dives were equilibrium disorder, sleep disturbances, fatigue, nausea, loose stools, stomach pain, tremor, mental disturbances, reduced appetite, and headache. Symptoms were scored individually by each diver. The symptoms were analyzed statistically by factor analysis, which grouped them into four factors. These symptoms are presumably related to functional disturbances in the brain stem and the cerebellum. Factor 3 symptoms (tremor, mental disturbances, reduced appetite) correlated significantly to a history of predive decompression sickness (P = 0.006) and to cerebral concussion (P = 0.023). Three divers were periodically unable to work at bottom due to equilibrium disorder, diarrhea, or nausea. One diver with mild polyneuropathy and slight cerebral atrophy as seen by computerized tomography and another diver with abnormal electroencephalography were periodically unable to work due to equilibrium disorder and nausea, respectively. We advocate that divers with signs of central or peripheral nervous system dysfunction should not be selected for deep diving.  相似文献   
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Background: Intensive insulin therapy in critically ill patients reduces morbidity and mortality. The current study elucidates whether acute hyperinsulinemia per se could attenuate the systemic cytokine response and improve neutrophil function during endotoxin (lipopolysaccharide)-induced systemic inflammation in a porcine model.

Methods: Pigs were anesthetized, mechanically ventilated, randomized into four groups, and followed for 570 min: group 1 (anesthesia solely, n = 10), group 2 (hyperinsulinemic euglycemic clamp [HEC], n = 9), group 3 (lipopolysaccharide, n = 10), group 4 (lipopolysaccharide-HEC, n = 9). Groups 3 and 4 were given a 180-min infusion of lipopolysaccharide (total, 10 [mu]g/kg). Groups 2 and 4 were clamped (p-glucose: 5 mm/l, insulin 0.6 mU [middle dot] kg-1 [middle dot] min-1) throughout the study period. Changes in pulmonary and hemodynamic function, circulating cytokines, free fatty acids, glucagon, and neutrophil chemotaxis were monitored.

Results: Tumor necrosis factor [alpha] and interleukin 6 were significantly reduced in the lipopolysaccharide-HEC group compared with the lipopolysaccharide group (both P = 0.04). In the lipopolysaccharide-HEC group, the glucagon response was diminished compared with the lipopolysaccharide group (P < 0.05). Serum free fatty acid concentrations were decreased in animals exposed to HEC. Animals receiving lipopolysaccharide showed an increase in pulmonary pressure (P < 0.001), but otherwise, there were no major changes in pulmonary or hemodynamic function. Neutrophil function was impaired after lipopolysaccharide administration.  相似文献   

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Sir, With great interest we read the article by Chang et al. [1]on the enhancement of epithelial sodium channel mRNA expressionand protein level in renal cortical collecting duct (CCD) cellsby advanced glycation end products (AGEs). The authors showthat AGEs can increase sodium uptake in CCD cells in a  相似文献   
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Host tissue response and heterotopic osteoinduction by composites of demineralized bone matrix and three different substances used as bioresorbable carriers implanted in the abdominal muscles were evaluated by strontium 85 uptake and histology 4 weeks postoperatively in 60 male Wistar rats. Both fibrin-collagen paste and fibrin sealant inhibited bone induction and produced a chronic inflammation; part of the fibrin-collagen paste was still present at 4 weeks. Polyorthoester with gentamicin was almost completely absorbed, induced minimal tissue reaction, and did not inhibit osteoinduction.  相似文献   
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Ergosine and its D-isolysergic acid derivative ergosinine were investigated on canine saphenous veins both in vivo and in vitro. Following local i.v. infusion in vivo, about 5 times higher doses of ergosinine were necessary to produce the same venoconstrictor response as induced by ergosine. When administered orally, however, both ergot alkaloids were equi-effective. In vitro methiothepin, a 5-HT receptor blocker with high affinity for 5-HT1 receptors, antagonized venoconstrictor responses to 5-HT and ergosine within the same concentration range, being significantly less potent when tested against norepinephrine. The reverse was true for the α2-selective adrenoceptor blocker yohimbine, which was significantly more potent against norepinephrine and ergosine than against 5-HT, suggesting that ergosine has affinity to both 5-HT1-like receptors and α2-adrenoceptors. Concentration-response curves to norepinephrine were shifted to the right in a parallel fashion when ergosine or ergosinine were present in the organ baths, suggesting competitive antagonism. The blocking potency of ergosinine increased with increasing incubation times in Krebs-Henseleit solution becoming similar to that of ergosine when an incubation time of 2 hr was applied. It is suggested that the pharmacological activity of ergosinine is the consequence of an isomerization into its natural stereoisomer ergosine, which may occur both in vivo and in vitro.  相似文献   
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PurposeComprehensive Geriatric Assessment (CGA) can identify health problems in older persons. In addition, CGA includes intervention towards the identified problems. With follow up, more problems may be identified and the interventions can be adjusted. We wanted to compare CGA with or without tailored follow-up in a randomised design.Patients and MethodsPatients 70+ years referred for oncology treatment with four primary tumour sites. Participants were randomised 1:1 to either control group with no follow-up or intervention group with a tailored follow-up by a multidisciplinary team. Primary outcome was adherence to cancer treatment. Secondary outcomes were daily life activities, physical performance and hospitalisation.ResultsIn total, 363 participants were randomised. After randomisation only 301 were planned to receive specific cancer treatment. Median age was 75 years. Among the 301 participants, 52% of control group vs. 61% of intervention group completed treatment. Risk Rate (RR): 1.16 (95% Confidence Interval (CI): 0.95–1.42), p = .14. The impact varied between the included tumour-sites, p < .01. We found no difference in 90 days physical performance or daily life activities between groups. During the study period, 55% of controls vs. 47% in the intervention group were admitted to hospital, RR: 0.86 (95%CI: 0.69–1.07), p = .19.ConclusionIn frail and vulnerable patients with cancer, a tailored follow-up on CGA showed no differences in ability to complete initially planned cancer treatment. The impact varied between the included tumour sites. We did not find any impact of tailored follow-up on daily life activities, physical performance or hospitalisation.  相似文献   
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