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排序方式: 共有7090条查询结果,搜索用时 11 毫秒
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.
《Vaccine》2020,38(39):6141-6152
Influenza vaccination is considered the most valuable means to prevent and control seasonal influenza infections, which causes various clinical symptoms, ranging from mild cough and fever to even death. Among various influenza vaccine types, the inactivated subunit type is known to provide improved safety with reduced reactogenicity. However, there are some drawbacks associated with inactivated subunit type vaccines, with the main ones being its low immunogenicity and the induction of Th2-biased immune responses. In this study, we investigated the role of a single-stranded RNA (ssRNA) derived from the intergenic region in the internal ribosome entry site of the Cricket paralysis virus as an adjuvant rather than the universal vaccine for a seasonal inactivated subunit influenza vaccine. The ssRNA adjuvant stimulated not only well-balanced cellular (indicated by IgG2a, IFN-γ, IL-2, and TNF-α) and humoral (indicated by IgG1 and IL-4) immune responses but also a mucosal immune response (indicated by IgA), a key protector against respiratory virus infections. It also increases the HI titer, the surrogate marker of influenza vaccine efficacy. Furthermore, ssRNA adjuvant confers cross-protective immune responses against heterologous influenza virus infection while promoting enhanced viral clearance. Moreover, ssRNA adjuvant increases the number of memory CD4+ and CD8+ T cells, which can be expected to induce long-term immune responses. Therefore, this ssRNA-adjuvanted seasonal inactivated subunit influenza vaccine might be the best influenza vaccine generating robust humoral and cellular immune responses and conferring cross-protective and long-term immunity.  相似文献   
3.
To compare nerve regeneration in young adult and aging mice, the right sciatic nerves of 6- and 24-month-old mice were crushed at the sciatic notch. Two weeks later, both groups of mice were perfused with an aldehyde solution, and, after additional fixation, the sciatic nerves were processed so that the transverse sections of each nerve subsequently studied by light and electron microscopy included the entire posterior tibial fascicle 5 mm distal to the crush site. The same level was sectioned in unoperated contralateral nerves; these nerves served as controls. Electron micrographs and the Bioquant Image Analysis System IV were used to measure areas of posterior tibial fascicles and count the number of myelinated axons, the number of unmyelinated axons, and their frequency in Schwann cell units. In aging mice, the total number of regenerating myelinated axons was significantly reduced, but totals of regenerating unmyelinated axons in aging and young adults did not differ significantly. In aging mice, the frequency of Schwann cells that contained a single unmyelinated axon was greater, suggesting that before myelination began, Schwann cell ensheathment of axons also was slowed. After axotomy by a crush injury, the area of the posterior tibial fascicle was less than that in young adults and the distal disintegration of myelin sheath remnants also appeared to be retarded. The results indicate that responses of neurons, axons, and Schwann cells could be important in slowing the regeneration of myelinated fibers found in sciatic nerves from aging mice.  相似文献   
4.
A case is presented of a patient with incessant venfricular tacbycardia of left bundle branch block morphology. Endocardial mapping revealed the site of earliest activation during tachycardia to be the proximal right ventricular septum. Pacing at this site elicited the clinical tachycardia, whereas pacing at the proximal left ventricular septum induced a right bundle branch block morphology identical to that of a previously recorded spontaneous ventricuiar tachycardia. Electrophysiological evidence is given that both types of tachycardia originate from a single reentry circuit located in the proximal ventricular septum in which the reentrant wavefront may travel either orthodromically (during spontaneous tachycardia and right ventricular pacing) or antidromically (during left ventricular pacing).  相似文献   
5.
目的:探讨异丙酚和芬太尼混合液静脉麻醉、笑气吸入麻醉及2%利多卡因宫颈局部浸润麻醉三种镇痛方法在人工流产手术中的疗效比较。方法:自2003年8月至2004年1月对236例妇科门诊早孕要求终止妊娠的妇女实施无痛人工流产术。随机分成3组。A组:异丙酚+芬太尼静脉麻醉(85例);B组:N2O(笑气)吸入麻醉(88例);C组:2%利多卡因宫颈局部浸润麻醉(63例),观察人流术中其镇痛效果并对疼痛进行分级。结果:A组85例100%可达到完全不痛(疼痛分级为0级);B组65.90%可达到完全不痛,Ⅰ级23.86%,Ⅱ级9.09%,Ⅲ级1.15%;C组0例可达到完全不痛,Ⅰ级63.49%,Ⅱ级30.16%,Ⅲ级6.35%。结论:受术者如无心肺疾患及人流禁忌证,无痛人工流产术应选择异丙酚+芬太尼静脉麻醉可达到完全无痛,痛苦最小。  相似文献   
6.
The structures of the developing eye-stalk and the relationships of early retinofugal fibers as they pass through the stalk, chiasm, and tract have been studied by light and electron microscopical methods in fetal ferrets aged 23–27 days. The early eye-stalk can be divided into two parts: a narrow extracranial part has a narrow lumen and is lined by few cells, whereas a thicker intracranial part has a wider lumen and is lined by several rows of cells. At the earliest stages no axon bundles are recognizable in the stalk, but fibers of the supraoptic commissure are already beginning to cross the midline in the diencephalon. Subsequently, as retinofugal axons invade the stalk, the glia of the extracranial part of the stalk have an interfascicular distribution and axon bundles are separately encircled by glial cytoplasm. In the intracranial part, as in the chiasm and tract, the glial cells occupy a periventricular position and send slender radial cytoplasmic processes to the subpial surface; these pass between groups of axons that here lie immediately deep to the subpial glia. Whereas axonal growth cones have no evident preferred distribution in the extracranial stalk, they tend to accumulate near the pial surface intracranially. The boundary between the two types of organization shifts as development proceeds so that the interfascicular glial structure of the early extracranial stalk first encroaches upon the intracranial parts and later appears in the chiasm. The characteristic adult arrangement of fibers in an age-related order in the optic chiasm and tract, but not in the optic nerve, can be understood if axonal growth cones are guided toward the pial surface by radial glia but not by interfascicular glia. From the distribution of the growth cones, this is what appears to happen.  相似文献   
7.
Abstract Several previous studies have evaluated the effects of 0.12% chlorhexidine digluconate (ChD) mouthrinses on plaque and gingival inflammation. However, previously, none have been based in general dental practices. The aim of this study was to evaluate the potential to conduct controlled periodontal clinical trials in co-operation with general dental practitioners (gdps). The project took place in 5 general dental practices in the South of England. 121 healthy subjects (24 at 4 sites and 25 at the 5th). aged 18-65 years, mean 35 ± 12) years participated in a double-blind, randomised study during which they received full mouth assessments for plaque and gingival bleeding at baseline, 6 and 12 weeks. 60 subjects were randomly asigned to use the 0.12% ChD mouth wash and 6i the placebo. The assessments were carried out by 5 gpds, who had previously achieved inter-examiner κ scores of 0.78–0.85 (mean 0.81) for the plaque index (PlI), and of 0.73–0.94 (mean 0.87) for a modified gingival index (mGI), and who maintained κ scores of 0.51–0.90 for PII and of 0.73–1.00 for mGI during the 12 months required to complete the study. 98 subjects (48 ChD and 50 placebo) completed the study. Even though the baseline levels of plaque and gingivitis were low, by week 12, mean whole mouth piaque score of the ChD mouthwash users had fallen from 1.33 at baseline to 0.96 and was significantly lower (p < 0.001) than for the placebo users, 1.31 at baseline to 1.13. Whole-mouth gingival bleeding score fell from 0.56 to 0.42 in the ChD mouthwash group but was unchanged (0.54–0.55) in the placebo group. A subsidiary data analysis which considered the effects at sites indicated that within these overall differences, the ChD users experienced almost 2× the reduction from plaque score 2 at baseline at proximal molar sites over a 12-week period (50.6% ChD versus 27.6% placebo). It was concluded that 0.12% ChD mouthwash reduced plaque accumulation fay 28% and gingival inflammation by 25% over a 12–week period, that it is feasible for a group of gdps to maintain high levels of inter–examiner consistency in the use of PlI and mGI, that it is also feasible to carry out such a multicentre study in general dental practice, and that the use of mean mouth scores per subject to analyse the effects of mouthrinses may well mask variations in response throughout the mouth.  相似文献   
8.
9.
The age-related changes in the total number of muscle fibers and motoneurons of the tibialis anterior and soleus muscles were studied using 10-, 65-, and 135-week-old rats. The number of fast twitch muscle fibers was decreased at age 65 weeks, while the numbers of slow twitch fibers and of alpha motoneurons were decreased only later, at age 135 weeks. Therefore, the degenerative process of muscle fibers differs with the fiber type.  相似文献   
10.
活性炭纤维在地方性氟中毒方面的应用展望   总被引:1,自引:0,他引:1  
曹守仁 《卫生研究》1994,23(2):77-79
介绍了活性炭纤维(ACFs)的制造,特性及其应用。它具有优异的结耕与性能特征。含碳量高,比表面积大,微孔丰富,从而吸附力强,而且活性炭纤维还可制成纱、布、毡等形状,它可用于去除燃煤氟中毒区室内空气中氟化氢、二氧化硫、氧化氮、氨等污染物,利用它的高吸附性能还可较好的去除饮水中的氟化物及其他有害物质。活性炭纤维是一种新型高效吸附材料。在氟中毒防治方面有广阔的前途。  相似文献   
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