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1.
Background/objectiveObstructive sleep apnea (OSA) is independently associated with dyslipidemia, a surrogate marker of atherosclerosis. Low-density lipoprotein (LDL)-cholesterol is accepted as a major independent risk factor for cardiovascular disease. However, non-high-density lipoprotein (HDL)-cholesterol is a better marker of atherogenic dyslipidemia and recommended as a target of lipid lowering therapy. We aimed to assess the prevalence of atherogenic dyslipidemia, and relationship between OSA severity and serum LDL-cholesterol and non-HDL cholesterol levels in OSA patients.MethodsWe retrospectively evaluated treatment naïve 2361 subjects admitted to the sleep laboratory of a university hospital for polysomnography. All subjects’ lipid profile including total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, and non-HDL-cholesterol were measured.ResultsOut of 2361 patients (mean age 49.6 ± 11.9 years; 68.9% male, apnea-hypopnea index 36.6 ± 28.4/h), 185 (7.8%) had no OSA and 2176 (92.2%) had OSA. Atherogenic dyslipidemia prevalence was high (57–66%) in OSA patients, and especially increased in severe OSA compared to other groups (p < 0.05). Though total and LDL-cholesterol did not differ between those with and without OSA, non-HDL-cholesterol (p = 0.020), and triglycerides (p = 0.001) were higher and HDL-cholesterol levels (p = 0.018) were lower in OSA patients than non-OSA. Non-HDL-cholesterol was significantly correlated with OSA severity (p < 0.001) and hypoxia parameters (p < 0.01), whereas LDL-cholesterol showed no correlation.ConclusionsAtherogenic dyslipidemia is highly prevalent and non-HDL-cholesterol levels are significantly increased, predominantly in severe OSA patients. Non-HDL-cholesterol but not LDL-cholesterol, is significantly correlated with OSA severity and hypoxia parameters. Therefore, it could be better to use non-HDL-cholesterol, which is a guideline recommended target of lipid therapy, as a marker of atherosclerotic cardiovascular risk in OSA patients.  相似文献   
2.
高压氧治疗急性一氧化碳中毒174例护理效果观察   总被引:5,自引:0,他引:5  
急性CO中毒是我国北方地区冬季的常见病,多发病。若治疗不及时或不彻底又有发生CO中毒迟发性脑病的危险。自从高压氧医学产生和发展以来,目前已成为CO中毒首选的主要治疗手段,取得了很好的治疗效果。本文对近3年来用高压氧(HBO)配合临床药物治疗CO中毒及迟发性脑病174例的治疗护理效果进行了观察,认为对急性CO中毒患者的治疗护理应及早发现、及早就医、及早HBO治疗并坚持足够的疗程,可以提高CO中毒的治愈率,降低死亡率,减少或减轻迟发性脑病的发生,同时认为整个HBO治疗过程中做好每个环节的护理工作是CO中毒患者救治成功的关键。1…  相似文献   
3.
高压氧综合治疗持续植物状态30例疗效分析   总被引:14,自引:0,他引:14  
目的评估高压氧综合治疗持续植物状态的疗效和探讨最佳治疗方案。方法回顾性分析了1999年—2005年应用高压氧治疗的30例持续植物状态病例,主要分析了原发病因、高压氧治疗次数以及高压氧治疗时机与疗效的关系。结果脑外伤组显效率和好转率明显高于非脑外伤组(P<0.05),开始治疗时间≤30d组及31~60d组好转率明显高于≥61d组(P<0.05)。结论高压氧综合治疗对脑外伤所致持续植物状态患者60d以内开始行高压氧治疗的患者疗效较好。  相似文献   
4.
目的:探讨活性氧(ROS)对人类精子线粒体tRNALeuUUR基因的氧化损伤。方法:采用Percoll梯度离心法筛选具有正常生理功能的精子,作为正常精子模型,并分为损伤组20例和对照组20例,分别加入次黄嘌呤-黄嘌呤氧化酶体系或不予处理,37℃有氧环境中孵育60min。分别提取精子DNA,以Fpg酶切损伤碱基并采用接头介导PCR(LM-PCR)检测线粒体tRNALeuUUR基因的氧化损伤。采用Rhodamine(Rh123)荧光探针标记精子,通过流式细胞仪检测线粒体膜电位,观察精子的功能。结果:与对照组相比,损伤组精子孵育后线粒体膜电位明显降低[(116.27±11.72)%vs(64.00±4.88)%,P<0.05]。Fpg酶切和LM-PCR显示精子线粒体tRNALeuUUR基因损伤。结论:ROS可能通过对精子线粒体tRNALeuUUR基因氧化损伤而影响精子功能(线粒体膜电位明显降低),从而引起不育。  相似文献   
5.
Reactive oxygen species and human spermatozoa: physiology and pathology   总被引:20,自引:1,他引:19  
The role of reactive oxygen species (ROS) in the pathophysiology of human sperm function has been emphasized in recent years. ROS production in semen has been associated with loss of sperm motility, decreased capacity for sperm–oocyte fusion and loss of fertility. There is a current presumption that the most prolific source of ROS in sperm suspensions is an NADPH oxidase located in leukocytes or in spermatozoa which produces superoxide which is further converted to peroxide by the action of superoxide dismutase. Hydrogen peroxide has been recognized as the most toxic oxidizing species for human spermatozoa, which are very sensitive to lipid peroxidation owing to the high content of polyunsaturated fatty acids in their plasma membrane, though this is not the sole mechanism by which sperm function might be impaired by ROS. Although the excessive production of ROS is detrimental to human spermatozoa, there is a growing body of evidence which suggests that ROS are also involved in the physiological control of some sperm functions. This review focuses on the nature and source of the ROS generated by human spermataozoa as well as their operational mechanisms and their effects, which may be detrimental or beneficial.  相似文献   
6.
Regulation of erythropoietin production   总被引:6,自引:0,他引:6  
  相似文献   
7.
BACKGROUND: Moderate hypothermia is one of the effective therapeutic methods for head injury in recent years, there are many mechanisms of moderate hypothermia for brain protection, and its influence on cerebral oxygenation is also one of them. OBJECTIVE: To observe the influence of moderate hypothermia on cerebral oxygenation of animals with acute intracranial hypertension, and further investigate the protective mechanism of moderate hypothermia. DESIGN: A randomized controlled trial. SETTING: Department of Neurosurgery, Renji Hospital affiliated to the Medical College of Shanghai Jiao Tong University. MATERIALS: Twenty healthy little pigs, either male or female, weighing 4.5–5.5 kg, were used. Neurotrend-typed multiparameter monitoring system (Diametrics Company, British); CMA/100 micro-injection pump (Carnegie Company, Sweden). METHODS: The experiment was conducted in the Changzheng Hospital affiliated to the Second Military Medical University of Chinese PLA in November, 2001. The pigs were randomized into two groups: the normothermia group (control group, n =10) and moderate hypothermia group (n =10). ① Bilateral femoral arteries were separated, one was connected to pressometer for monitoring mean arterial pressure (MEP), and the other for analysis of blood gases [including peripheral blood pH value, arterial partial pressure of carbon dioxide (PaCO2), arterial partial pressure of carbon dioxide (PaCO2), HCO3–]. ② Rectal temperature was monitored with mercurial thermometer. ③ Intracranial pressure was monitored using Camino optic ICP probe placed in the subdural space. ④ Neurotrend multiparameter monitoring sensor was inserted into the white matter for about 4 cm to determine cerebral perfusion pressure (CPP, CPP=MAP(ICP), brain tissue partial oxygen pressure (PO2), partial pressure of carbon dioxide (PCO2), HCO3– and brain temperature. The rectal temperature of animals in the moderate hypothermia group was lowered to 34 ℃ using ice bags, and the body temperature was maintained at 33–35 ℃ for 2 hours. The changes of the parameters were observed continuously, and the pigs in the normothermia group were not treated with cooling. MAIN OUTCOME MEASURES: ① MAP, ICP, rectal temperature, CCP; Indexes of cerebral oxygenation detected with Neurotrend-typed multiparameter monitoring system; ② Results of blood gases analysis in the moderate hypothermia group. RESULTS: All the 20 pigs were involved in the analysis of results. ① MAP, ICP, rectal temperature, CCP and indexes of cerebral oxygenation: In the moderate hypothermia group, the ICP after cooling was obviously lower than that before cooling [(3.31±1.19), (5.33±0.95) kPa, P < 0.05], CCP was higher, brain tissue PCO2 [(12.03±1.73), (10.59±2.01) kPa, P < 0.05], and brain tissue pH value was higher [(7.03±1.63), (9.40±1.30) kPa, P < 0.05], whereas the brain temperature was decreased as compared with that before cooling [(34.9±0.3), (37.2±0.2) ℃, P < 0.05]. ② Results of blood gases analysis in the moderate hypothermia group: There were no significant differences in the parameters of peripheral arterial blood gases analysis before and after cooling in the moderate hypothermia group (P > 0.05) CONCLUSION: Moderate hypothermia will not impair the cerebral oxygenation, and it can reduce brain tissue CO2 and decrease brain tissue acidosis.  相似文献   
8.
活性氧簇是重要的氧的衍生物,氧化还原反应状态的平衡对维持机体的内环境起着重要的作用.皮肤是氧应激损害的主要靶器官,过多活性氧造成组织损伤,其主要通过影响核因子-κB、NO、蛋白激酶介导的磷酸化和基因异常表达发挥作用.多种炎症性皮肤疾病与活性氧簇相关,活性氧簇在皮炎、湿疹的发病中起着重要作用,抗氧化剂有望成为治疗这类疾病的新途径.  相似文献   
9.
The effects of cepharanthin on inflammatory parameters such as neutrophil chemotaxis, phagocytosis and reactive oxygen species (ROS) generation, were examined. Cepharanthin significantly decreased the levels of O2-, H2O2, and OH. generated by neutrophils. H2O2 and OH. generated in a cell-free, xanthine-xanthine oxidase system were also reduced in the presence of cepharanthin. However, the drug did not affect neutrophil chemotaxis or phagocytosis. The present study indicates that cepharanthin is an effective ROS scavenger, exerting its anti-inflammatory action by reducing the potent ROS species excessively generated in tissues and organs, especially at the sites of inflammation.  相似文献   
10.
Oxygen uptake during running, i.e., the running economy, is an important factor in determining running performance in endurance events. The relation to performance is particularly strong when the aerobic running capacity is calculated, i.e., when running economy is related to the maximal oxygen uptake. There is considerable interindividual variation in running economy, and the reason for this is only partly understood. To some extent, this may be due to the way in which the oxygen uptake during running is usually expressed. This may expecially be true when subjects with different or changing body masses are compared. Several lines of evidence, including earlier animal studies as well as more recent human studies, favor the expression of submaximal and maximal oxygen uptake during running in terms of ml · kg−0.75· min−1 rather than as ml · kg−1· min−1.  相似文献   
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