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101.
Parkinson's disease (PD) is the second most common neurodegenerative disorder characterized by a selective loss of nigrostriatal dopaminergic neurons. Clinical manifestations of this complex disease include resting tremor, bradykinesia, postural instability, gait difficulty and rigidity. Approximately 5%-10% of patients have genetic factors, yet etiology of PD remains unclear. Genetic deficits, environmental exposure, oxidative stress, mitochondrial dysfunction,  相似文献   
102.
目的 研究HIV-1膜蛋白(Env)特定中和表位的改造对功能性假病毒形成及中和活性的影响.方法 采用环形诱变及Dpn I筛选的方法对Env进行定点突变,将2G12和2F5两个中和表位整合入不含该表位的BC亚型的Env上,比较改造对假病毒的形成情况及对2G12和2F5单抗的中和活性的影响.结果 对5株假病毒(BC02、BE03、BC04、BC05和BC12)的Env特定中和表位进行改造,其中BC04和BCl2的2G12表位改造后,不能形成假病毒,BC02、BC03和BC05增加2G12和2F5两个表位后,仍能够形成假病毒,且假病毒滴度较改造前无明显变化,改造后的BC03假病毒较改造前对单抗2G12和2175的中和活性均有所提高,而改造后的BE02和BC05假病毒较改造前对单抗2F5的中和活性增强,而对单抗2G12的中和活性无变化.结论 2G12中和表位部分位点的改造影响假病毒的形成,中和表位的增加能够提高单抗2G12的中和活性,为免疫原的优化提供了新思路.  相似文献   
103.
借鉴军队院校管理模式 推行量化考评规范实习生管理   总被引:1,自引:0,他引:1  
本文通过对当前军队医院实习生管理现状的分析,探讨了军队院校管理模式、量化考评在医院实习生管理中的作用,提出了一些具体的工作方法和措施。  相似文献   
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105.
Nocturnal blood pressure (BP) surge in seconds (sec-surge), which is characterized as acute transient BP elevation over several tens of seconds is induced by obstructive sleep apnea (OSA) and OSA-related sympathetic hyperactivity. The authors assessed the relationship between sec-surge and arterial stiffness in 34 nocturnal hypertensive patients with suspected OSA (mean age 63.9 ± 12.6 years, 32.4% female). During the night, they had beat-by-beat (BbB) BP and cuff-oscillometric BP measurements, and brachial-ankle pulse wave velocity (baPWV) was assessed as an arterial stiffness index. Multiple linear regression analysis revealed that the upward duration (UD) of sec-surge was significantly associated with baPWV independently of nocturnal oscillometric systolic BP variability (β = .365, p = .046). This study suggests that the UD of sec-surge, which can only be measured using a BbB BP monitoring device, may be worth monitoring in addition to nocturnal BP level.  相似文献   
106.

Background

The semiactive or inactive probiotics or their extracts used in dermatology have interesting properties to ameliorate signs of irritated skin and enhance the skin barrier. Bifidobacterium, as the most common probiotics, which has been found to be effective in reducing acne and improving the skin barrier function of atopic dermatitis. Bifida Ferment Lysate (BFL) can be obtained from Bifidobacterium by fermentation and extraction.

Purpose

In this study, we investigated the effect of a topically used BFL on the skin using in vitro evaluation methods.

Results

The results showed that upregulation of skin physical barrier gene (FLG, LOR, IVL, TGM1, and AQP3) and antimicrobial peptide gene (CAMP and hBD-2) in HaCaT cells by BFL might be responsible for skin barrier resistance. In addition, BFL had strong antioxidant properties representing a dose-dependent increasing of the scavenging capacity of DPPH, ABTS, hydroxyl, and superoxide radicals. BFL treatment also fundamentally inhibited the intracellular ROS and MDA production and improved the activities of antioxidant enzymes (CAT and GSH-Px) in H2O2-stimulated HaCaT cells. As a good immunomodulatory factor, BFL efficiently decreased the secretion of IL-8 and TNF-α cytokines, and COX-2 mRNA expression in LPS-induced THP-1 macrophages.

Conclusion

BFL can strengthen the skin barrier function and stimulate skin barrier resistance, to reinforce the skin against oxidative stress and inflammatory stimuli.  相似文献   
107.
108.
As a method to control patient flow to overburdened hospitals, effective emergency medical services (EMS) systems provide policies for ambulance diversion. The Maryland state EMS system supports two types of alert for general hospital use: red alert, aimed at limiting the delivery of patients who may require intensive care unit (ICU) admission, and yellow alert, aimed at preventing further overload of already overtaxed emergency departments (EDs). OBJECTIVE: To examine the effect of those alert policies in different geographical environments, urban, suburban, and rural. METHODS: Alert data for 23 hospitals in Central Maryland and ambulance arrival data for approximately 138,000 ambulance calls during calendar year 1996 were combined and analyzed. The impacts of diversion practices in the geographic areas were compared. RESULTS: Red alert reduced volume in all patient acuity levels in all geographic areas by a statistically significant 0.4 patient/hr. Yellow alert diverted low-acuity patients at the rate of 0.13 patient/hr (p<0.001) in urban areas and at the rate of 0.16 patient/hr (p<0.001) in suburban areas, but had minimal impact in the flow of patients in the rural environment. CONCLUSIONS: The ED diversion policy has some limited effect in preventing further patient volume in urban and suburban areas, but has virtually no impact in rural areas. However, an ICU diversion policy diverts patients of all acuities uniformly and inordinately diverts patients not likely to require ICU admissions while having only minimal impact on patients who do require ICU resources. The impact of red alert is uniform in all geographic areas. The impact and efficacy of ambulance diversion policies should be evaluated to ensure they are having the intended effect. While perhaps initially effective, the impact of alert policies may change over time.  相似文献   
109.
The sequence effect (SE) in Parkinson's disease (PD) is progressive slowing of sequential movements. It is a feature of bradykinesia, but is separate from a general slowness without deterioration over time. It is commonly seen in PD, but its physiology is unclear. We measured general slowness and the SE separately with a computer‐based, modified Purdue pegboard in 11 patients with advanced PD. We conducted a placebo‐controlled, four‐way crossover study to learn whether levodopa and repetitive transcranial magnetic stimulation (rTMS) could improve general slowness or the SE. We also examined the correlation between the SE and clinical fatigue. Levodopa alone and rTMS alone improved general slowness, but rTMS showed no additive effect on levodopa. Levodopa alone, rTMS alone, and their combination did not alleviate the SE. There was no correlation between the SE and fatigue. This study suggests that dopaminergic dysfunction and abnormal motor cortex excitability are not the relevant mechanisms for the SE. Additionally, the SE is not a component of clinical fatigue. Further work is needed to establish the physiology and clinical relevance of the SE. © 2010 Movement Disorder Society.  相似文献   
110.
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