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21.
Guillain-Barr啨综合征(GBS)和Miller Fisher综合征(MFS)的诊断标准随着临床研究的深入在不断演变。2011年1月,《疫苗》杂志发表了国际疫苗安全性监测Brighton合作组关于GBS/MFS的诊断定义和研究资料收集规范。此文献中未采用"诊断标准"而采用"诊断定义"是因为其主要目的为评价疫苗安全性而制定,而非用于神经科的GBS/ 相似文献
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Anastasia Zotou Athina Siampalioti Panagiota Tagari Leonidas Paridis Fotis Kalfarentzos Kriton S. Filos 《Obesity surgery》2014,24(12):2099-2108
Background
Insufficient data exist regarding postoperative thoracic epidural analgesia for morbidly obese patients undergoing open bariatric surgery. This study evaluated the effectiveness of morphine loading in a postoperative thoracic epidural analgesic regimen of patient-controlled epidural analgesia (PCEA) with levobupivacaine combined with continuously administered epidural morphine in this patient group.Methods
In this prospective randomized controlled trial, 48 superobese patients (body mass index of ≥50 kg/m2) undergoing open bariatric surgery were randomly allocated to three groups of 16 patients each. Postoperatively, all groups received a continuous epidural morphine infusion of 0.2 mg/h with 0.1 % levobupivacaine via PCEA. Group A did not receive intraoperative epidural morphine loading, while groups B and C received an intraoperative 1- and 2-mg morphine bolus, respectively. Levobupivacaine consumption via PCEA (primary outcome), pain scores at rest and on cough, the time to return of bowel function and ambulation, and arterial blood gas levels (secondary outcomes) were recorded.Results
The increase in perioperative morphine administration (groups B and C) led to a significantly prolonged return to normal bowel function and delayed ambulation (P?0.05 to 0.01, respectively), without an improvement in postoperative analgesia or a reduction in local anesthetic consumption. Although the prevalence of obstructive sleep apnea (OSA) was high in all groups, no respiratory depression was observed.Conclusions
Thoracic PCEA with 0.1 % levobupivacaine combined with continuous epidural morphine administration of 0.2 mg/h without morphine loading is an effective postoperative analgesic regimen that provides adequate pain control, early ambulation, and early return of bowel function in superobese patients, particularly those with OSA. 相似文献24.
25.
Eosinophils stimulate fibroblast DNA synthesis 总被引:9,自引:0,他引:9
Fibrosis complicates a number of chronic inflammatory diseases and occurs in some conditions following chronic hypereosinophilic syndromes. We assessed whether eosinophils might be a source of fibrogenic factors. Extracts of human and guinea pig cell populations enriched for eosinophils contained substances that stimulated tritiated thymidine incorporation by human fibroblasts. Supernatants derived from resting eosinophils and extracts prepared from eosinophil granules also contained fibrogenic factors. Our findings demonstrate a new potential role for eosinophils and suggest a causal relationship between tissue eosinophilia and scar formation in certain parasitic conditions. 相似文献
26.
Deficiency of platelet membrane glycoprotein Ia associated with a decreased platelet adhesion to subendothelium: a defect in platelet spreading 总被引:14,自引:5,他引:14
A bleeding disorder with absent collagen-induced platelet aggregation and adhesion has been described in a patient whose platelets failed to express surface glycoprotein Ia. We studied the interaction of her platelets with subendothelium in an annular perfusion chamber and the interaction with purified human collagen type III in a rectangular perfusion system under flow conditions. Platelet adherence was almost completely absent both at low and high shear rates. The few platelets which adhered remained in the contact stage without subsequent spreading and aggregate formation. Addition of a monoclonal antibody, which was directed against the von Willebrand moiety of FVIII-VWF, to the blood, completely abolished platelet adherence at high shear rates and had a partial effect at low shear rates. These data indicate that von Willebrand factor plays a role in the initial attachment (contact stage) of platelets to subendothelium. We conclude that the bleeding disorder and excessively prolonged bleeding time in our patient are caused by a new specific defect of the platelet-vessel wall interaction. 相似文献
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The role of divalent cations in platelet adherence to deendothelialized human arteries in flowing blood was investigated in an annular perfusion chamber. Spreading of platelets on the subendothelium was impaired below 30 microM of free Ca2+ ions (Ca2+). When Ca2+ was replaced by Mg2+, adherence was unchanged in perfusates without exogenous factor VIII-von Willebrand factor (FVIII-vWF), but the ability of FVIII-vWF to support platelet adherence was lost. Binding of FVIII-vWF to the vessel wall was independent of divalent cations, but bound FVIII-vWF was only able to mediate adherence after exposure to Ca2+. Pretreatment of FVIII-vWF with the calcium chelator EGTA (10 mM) resulted in loss of the ability to facilitate platelet adherence, while the ristocetin cofactor activity remained intact. Full restoration of the ability to mediate platelet adherence could only be obtained by prolonged dialysis against Ca2+ in the millimolar range. These data indicate that divalent cations have at least two separate roles to play in supporting platelet adherence: (1) platelet spreading on the subendothelium requires Ca2+ or Mg2+; (2) FVIII-vWF should be exposed to Ca2+ to obtain its optimal biologic activity in supporting platelet adherence. 相似文献
30.
Effects of positive and negative pressure ventilation on cerebral blood volume of newborn infants 总被引:3,自引:0,他引:3
KS Palmer SA Spencer YABD Wickramasinghe T Wright DP Southall P Rolfe 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(2):132-139
The effects of intermittent positive airway and continuous negative extrathoracic pressure ventilation on cerebral blood volume in preterm infants were studied using near infrared spectroscopy. In 12 infants continuous negative extrathoracic pressure caused a median decrease in cerebral blood volume of 0.14ml/100ml brain (95% confidence intervals (CI) 0.035–0.280) compared with no respiratory support. Oxygenated and deoxygenated haemoglobin also decreased, implying increased venous drainage as the main effect. In 17 infants intermittent positive pressure ventilation also caused a median reduction in cerebral blood volume of 0.06 ml/100 ml brain (95% CI 0.010–0.115) compared with endotracheal positive airway pressure. Deoxygenated haemoglobin increased by 0.07 ml/100 ml brain (95% CI 0.010–0.100) while oxygenated haemoglobin decreased by O.lOml/lOOml brain (95% CI 0.005–0.175). The increase in deoxygenated haemoglobin implies decreased venous drainage and the decrease in oxygenated haemoglobin implies that other factors may also be significant. Heart rate, blood pressure and oxygen saturation were monitored continuously and remained stable. 相似文献