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41.
慢性阻塞性肺疾病前驱性呼吸衰竭患者呼吸驱动的改变 总被引:15,自引:4,他引:11
目的探讨慢性阻塞性肺疾病(COPD)和COPD前驱性呼吸衰竭(前驱呼衰)患者中枢呼吸驱动的改变;评价界定COPD前驱性呼吸衰竭的临床意义.方法试验对象为COPD前驱性呼吸衰竭、COPD尚未达前驱性呼吸衰竭的患者和健康对照者各30名.所有受试者均进行如下参数的测定:动脉血气分析;常规肺功能,主要以第1秒用力呼气容积(FEV1)占预计值的百分比(FEV1%)来评价;中枢呼吸驱动水平,以0.1 s口腔阻断压(P0.1)、校正中枢呼吸驱动(以每分通气量来校正,即P0.1/MV)和吸气阻抗P0.1/VT/Ti)等来评价.结果P0.1和P0.1/MV在COPD前驱呼衰组明显高于正常对照组和未达前驱呼衰组,P0.1/VT/Ti在COPD前驱呼衰组和未达前驱呼衰组明显高于正常对照组(P=0.002);P0.1,P0.1/MV,P0.1/VT/Ti与PaO2,FEV1%呈显著负相关(rs=-0.769,-0.495,-0.543;-0.747,-0.480,-0.526,P均<0.01);与PaCO2呈显著正相关(rs=0.270,0.312,0.369,P分别为<0.05,<0.01,<0.01).结论COPD前驱呼衰患者呼吸储备能力减低,呼吸效率下降;P0.1,P0.1/MV,P0.1/VT/Ti等参数在推断患者神经-肌力输出水平与呼吸衰竭发生阈值方面具有较大的意义.当COPD进展至前驱呼衰阶段,从血气分析、肺功能检查到呼吸驱动水平都发生了显著的改变,从而提示界定此阶段具有一定的临床意义. 相似文献
42.
褪黑素对结肠黏膜上皮细胞氧化应激的影响 总被引:3,自引:1,他引:2
目的 探讨褪黑素对大鼠结肠黏膜上皮细胞氧化应激的影响。方法 在分离培养正常大鼠结肠黏膜上皮细胞基础上,利用FeSO4 H2O2产生*OH攻击制备结肠黏膜细胞氧化损伤模型,同时预先加入褪黑素并观察损伤减轻程度。实验设正常对照组、模型对照组、5-氨基水杨酸给药组(0.1mmol/L),褪黑素给药组(0.01、0.1、l.0mmol/L)。培养一定时间后,取上清测乳酸脱氢酶(LDH)、丙二醛(MDA)、谷胱甘肽过氧化物酶(GSHPx)、过氧化氢酶(CAT)、超氧化物歧化酶(SOD)、一氧化氮(NO)和黏液含量。结果 模型组大鼠结肠黏膜上皮细胞:MDA、LDH和NO水平增高,CAT、GSHPX、SOD和黏液含量减少。不同剂量褪黑素呈剂量依赖性的减少LDH释放,抑制MDA和NO的形成,恢复黏液、CAT、GSHPX及SOD水平。结论 褪黑素对大鼠结肠黏膜氧化损伤具有保护作用。 相似文献
43.
Patientsfeelimpatientbecausetheycouldnotpredicttheonsettimeofepilepsy.Ifonsettimeofepilepsycouldbepreciselypredicted,thendrugadministrationanddisabilityofpreventionwillbecomeavailable.In1879,Echevarrzafoundonsettimeofepilepsyisdistributedaccordingtosomerules.Inrecentyears,scientistsperformalotstudiesinvolvingcytologyandmolecularbiologyofepilepsy.Clinicaldataindicatedonsetofepilepsyhascloserelationwithbiologicalrhythmsuchasawakeandsleepcycleandmenstrualcycle.Theobjectiveofthisstudy… 相似文献
44.
目的:探讨加速儿童髋关节一过性滑膜炎疾病的愈合.方法:随机性分析2005年1月~2006年4月共100例髋关节一过性滑膜炎患儿的治疗效果,把病人随机分为治疗组及对照组.治疗组按常规方法治疗加TDP灯局部照射,对照组仅按常规方法治疗.结果:治疗1周后,治疗组B超检查增厚滑膜厚度变化差值、关节腔间隙宽度变化值、关节腔积液好转率、"4"字试验阴性率均明显优于对照组(P<0.05).结论:TDP灯用于治疗儿童髋关节一过性滑膜炎能加速疾病愈合,提高治疗效果. 相似文献
45.
红斑反应与理想光子嫩肤术关系的研究 总被引:1,自引:0,他引:1
目的 观察红斑反应与理想光子嫩肤术的关系,为临床提供参考.方法 采用34 J/cm2的强脉冲光,对10只兔子(4个部位)分别照射1、2、3、4次,记录出现红斑反应的照射次数,术后第15天观察治疗部位切片,记录使皮肤真皮胶原蛋白增生的照射次数.结果 红斑反应的阈刺激照射次数是(2.60±0.52)次,真皮胶原蛋白增生的阈刺激照射次数是(3.00±0.67)次.两者比较无显著差异.结论 IPL致红斑反应的能量大小,与理想光子嫩肤术所需的能量接近. 相似文献
46.
V Schleyer† S Radakovic-Fijan‡ S Karrer† T Zwingers§ A Tanew‡ M Landthaler† RM Szeimies† 《Journal of the European Academy of Dermatology and Venereology》2006,20(7):823-828
BACKGROUND: Based on good results in the treatment of superficial skin tumours, since the early 1990s topical photodynamic therapy with aminolaevulinic acid (ALA PDT) has been used for disseminated, inflammatory dermatoses including psoriasis. However, there is still a lack of well-documented trials. OBJECTIVE: A prospective randomized, double-blind phase I/II intrapatient comparison study was conducted in 12 patients to investigate whether topical ALA PDT is an effective treatment for chronic plaque-type psoriasis. METHODS: In each patient three psoriatic plaques were randomly treated with a light dose of 20 J/cm(2) and 0.1%, 1% and 5% ALA, respectively. Treatment was conducted twice a week until complete clearance or for a maximum of 12 irradiations. Therapeutic efficacy was assessed by weekly determination of the psoriasis severity index (PSI). RESULTS: The mean percentage improvement was 37.5%, 45.6% and 51.2% in the 0.1%, 1% and 5% ALA-treated groups, respectively. Irradiation had to be interrupted several times because of severe burning and pain sensation. CONCLUSION: Topical ALA PDT did not prove to be an appropriate treatment option for plaque-type psoriasis due to disappointing clinical efficacy, the time-consuming treatment procedure and its unfavourable adverse event profile. 相似文献
47.
Imad Ghorayeb MD PhD Anderson Loundou PhD Pascal Auquier MD Yves Dauvilliers MD PhD Bernard Bioulac MD PhD François Tison MD PhD 《Movement disorders》2007,22(11):1567-1572
To determine the prevalence of excessive daytime sleepiness (EDS) and that of dozing and sudden onset of sleep episodes (SOS) while driving in ambulatory patients with Parkinson's disease (PD) in France, a national sample of private and public neurologists was asked to recruit the first 10 consecutive nondemented PD patients. Each patient completed a questionnaire including the Epworth Sleepiness Scale (ESS) and the likelihood of dozing off and experiencing SOS episodes behind the wheel. Clinical and demographic data were collected. One thousand six hundred and twenty‐five patients with PD were included in the survey. Twenty‐nine percent of the patients suffered from EDS (ESS score ≥10) but only 0.8% declared a high chance of dozing while driving and 0.5% reported totally unpredictable SOS episodes while driving. Risk factors for EDS were male gender, reduced activity of daily living, and a high daily levodopa equivalent dosage. Risk factors for SOS episodes while driving were an ESS score ≥10, male gender, and low Hoehn and Yahr staging. EDS is common in ambulatory patients with PD and is a major risk factor for dozing and for SOS episodes behind the wheel in patients who drive. © 2007 Movement Disorder Society 相似文献
48.
Anthony P Cullen Olanrewaju M Oriowo Anita C Voisin 《Clinical & experimental optometry》1997,80(3):80-86
Concern about short- and long-term ultraviolet radiation (particularly UVB) damage to the eye has led to increased research in this area. Numerous studies have confirmed the pathogenic enhancing roles of reflected ultraviolet (UV) and visible radiation in our environment. There is concern that conventional sunglasses do not protect the eye adequately from reflected rays (albedo), especially on the lateral aspect, from behind and from below. Using eye models and computer ray tracing methods, the pathways of oblique rays incident at the temporal peripheral cornea have been plotted by Maloof, Ho and Coroneo.1 These rays are refracted and focused and theoretically can result in up to 20 times the concentration of incident irradiance at the nasal anterior chamber angle and nasal equatorial cortex of the crystalline lens. The purpose of this study was to determine the limits of angular subtense of the incident peripheral light which is refracted in this manner in human subjects and to investigate the relation between corneal shape and certain ocular parameters to the limits. A statistically significant positive correlation was found between temporal entrance angle and anterior chamber depth (r = 0.70, P< 0.0006). The entrance angle ranged from 15 degrees to 30 degrees and was located 10 degrees to 45 degrees posterior to the coronal plane. Our results support Maloof and colleagues' predictions for the implication of focused peripheral UV and high intensity visible radiation in the pathogenesis of pterygium and cortical cataract and emphasise the need for lateral eye protection in conditions of high ultraviolet albedo. 相似文献
49.
Ilham Bettahi David Pozo Carmen Osuna Russel J. Reiter Dario Acuña-Castroviejo Juan M. Guerrero 《Journal of pineal research》1996,20(4):205-210
Abstract: In this report, rat hypothalamic nitric oxide synthase (NOS) activity is shown to be partially inhibited by physiological concentrations of the pineal hormone melatonin. In vitro studies demonstrate that 1 nM melatonin, which approximates the physiological concentration of the hormone at night, significantly inhibited NOS activity. In vivo studies show that administering melatonin or collecting the hypothalamus from animals at night, when endogenous melatonin levels are elevated, results in a significant decrease of NOS activity. Results also show that calmodulin may be involved in this process since its presence in the incubation medium prevents the inhibitory effect of melatonin on NOS activity. 相似文献
50.
The pineal gland and reproduction 总被引:2,自引:0,他引:2
The hormonal activity of the pineal gland is influenced by boththe dark-light cycle and the seasonal cycle, causing it to playan important role in the neuroendocrine control of reproductivephysiology. This is especially evident in seasonally breedinganimals, in which reproductive function is clearly influencedby seasonal variations in the duration of night and day. Humansare not seasonal breeders. Nevertheless, seasonal fluctuationshave been described in human reproduction, and the pineal glandalso appears to exert an important role in the neuroendocrineregulation of human reproductive physiology. There is evidencethat the epiphysis is involved in the control of sexual maturation.In rats, the maternal pineal appears to influence the gonadaland genital development and function of offspring; this hypothesishas yet to be confirmed in humans. The pineal apparently influenceshuman reproductive function not only at the hypothalamic-pituitarylevel, by inhibition of the hypothalamic pulsatile secretionof gonadotrophin-releasing hormone, but also at the gonadallevel, where melatonin receptors have also been found. In addition,melatonin is reported to increase serum prolactin concentrationsin both rats and humans. It has been suggested that melatoninis involved in the control of menstrual cyclicity. 相似文献