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71.
MR appearance of two patients with large, orbital conjunctival epithelium-lined inclusion cysts are presented. Both were complications of ophthalmic surgical procedures that necessitated conjunctival incision.  相似文献   
72.
目的:探讨西脉镍钛形状记忆合金环抱器用于骨折内固定术有关的护理配合问题。方法:12例不同部位骨折病人(其中男性8例、女性4例、年龄15~62岁)采用西脉镍钛(TiNi)形状记忆合金环抱器人实施内固定手术,观察术中护理配合要点和实际效果。结果:骨折复位满意,手术持续时间<2h。所有病人术后均无感染迹象,手术切口愈合良好。结论:围术期护理配合质量(如器械选择、塑形准备、无菌操作等)的优劣,是手术成功与否的重要因素之一。  相似文献   
73.
BACKGROUND: This study investigated the utility of the alveolar - arterial oxygen pressure difference (AaDO (2)) in predicting the short-term prognosis of acute pulmonary embolism (PE). METHODS AND RESULTS: This study retrospectively enrolled 114 consecutive patients with acute PE, diagnosed by either spiral computed tomography or high probability ventilation - perfusion lung scans. During the first 24 h of admission, all patients had initial artery blood gas collected under room air. Patient exclusion criteria were chronic lung disease, septic emboli, and moderate and low probability lung scans. Patients were assigned to 2 groups based on either 30-day death or a 30-day composite event. Receiver operating characteristic analyses was used to determine the AaDO(2) cut-off value for predicting primary and composite endpoints. Statistical analysis demonstrated significant differences in AaDO(2) between the 30-day composite endpoint group and the 30-day composite event-free survival group (p=0.012). The AaDO(2) had a strong trend between the 30-day death group and the survival group (p=0.062). The best cut-off value for AaDO(2) was 53 mmHg and using this, the positive predictive value for 30-day death was 25% and the negative predictive value was 92%. For the 30-day composite endpoint, the positive predictive value for AaDO(2) was 35%, and the negative predictive value was 84%. In this study, thrombocytopenia was also an indicator of poor prognosis for patients with acute PE. CONCLUSION: The AaDO(2) measurement is a highly useful and simple measurement for predicting short-term prognosis in patients with acute PE. It has high negative predictive value and moderate positive predictive value for 30-day death and 30-day composite event. Aggressive thrombolytic treatment strategies should be considered for patients with an initial poor prognostic parameter (ie, AaDO(2) >or=53 mmHg).  相似文献   
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Amniotic fluid mesenchymal stem cells have the ability to secrete neurotrophic factors that are able to promote neuron survival in vitro. The purpose of this study was to evaluate the effects of neurotrophic factors secreted by rat amniotic fluid mesenchymal stem cells on regeneration of sciatic nerve after crush injury. Fifty Sprague-Dawley rats weighing 250-300 g were used. The left sciatic nerve was crushed with a vessel clamp. Rat amniotic fluid mesenchymal stem cells embedded in fibrin glue were delivered to the injured nerve. Enzyme-linked immunosorbent assay (ELISA) and immunocytochemistry were used to detect neurotrophic factors secreted by the amniotic fluid mesenchymal stem cells. Nerve regeneration was assessed by motor function, electrophysiology, histology, and immunocytochemistry studies. Positive CD29/44, and negative CD11b/45, as well as high levels of expression of brain-derived neurotrophic factor, glia cell line-derived neurotrophic factor, ciliary neurotrophic factor (CNTF), nerve growth factor, and neurotrophin-3 (NT-3) were demonstrated in amniotic fluid mesenchymal stem cells. Motor function recovery, the compound muscle action potential, and nerve conduction latency showed significant improvement in rats treated with amniotic fluid mesenchymal stem cells. ELISA measurement in retrieved nerves displayed statistically significant elevation of CNTF and NT-3. The immunocytochemical studies demonstrated positive staining for NT-3 and CNTF in transplanted cells. The histology and immunocytochemistry studies revealed less fibrosis and a high level of expression of S-100 and glial fibrillary acid protein at the crush site. Rat amniotic fluid mesenchymal stem cells may facilitate regeneration in the sciatic nerve after crush injury. The increased nerve regeneration found in this study may be due to the neurotrophic factors secreted by amniotic fluid mesenchymal stem cells.  相似文献   
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The retrosplenial cortex is a cytoarchitecturally distinct brain structure located in the posterior cingulate gyrus and bordering the splenium, precuneus, and calcarine fissure. Functional imaging suggests that the retrosplenium is involved in memory, visuospatial processing, proprioception, and emotion.We report on a patient who developed reversible verbal and visual memory deficits following a stroke. Neuropsychological testing revealed both anterograde and retrograde memory deficits in verbal and visual modalities. Brain diffusion-weighted and T2-weighted magnetic resonance imaging (MRI) demonstrated an acute infarction of the left retrosplenium.  相似文献   
80.
S Yu  I K Ho 《Alcohol》1990,7(3):261-272
Central nervous system depressants, e.g., barbiturates, alcohol and benzodiazepines, have a wide spectrum of activity in humans and animals. Evidence accumulated suggests that some of the pharmacological actions exerted by these agents may be mediated through GABA system by mimicking GABAergic transmission. This review attempts to summarize the evidence available as to how the GABA system plays a part in the barbiturate actions and the development of tolerance to and physical dependence on barbiturates. The comparisons of the effects of alcohol, barbiturates and benzodiazepines at different steps of GABA synapse are also presented. Furthermore, the results which have been reported in the literature are inconsistent. This may be due to differences in: (a) animal models used; (b) brain regions used; (c) protocols (dose, duration, form and route of administration, etc.) used in treating animals and/or (d) techniques (pharmacological, biochemical, physiological, etc.) used.  相似文献   
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