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81.
目的:研究雌孕激素对ALI大鼠II型肺泡上皮细胞钠通道(epithelial Na+channel,ENaC)α亚基,血清脑钠肽(brain natriuretic peptide,BNP)和肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)表达的影响,探讨肺泡内液体清除的机制。方法:雌性未成年SD大鼠30只,随机分为3组:对照组(静脉注入生理盐水8 mL/kg)、ALI模型组(静脉注入油酸0.1 mL/kg)、雌孕激素联合组(在油酸注入前12 h、36 h皮下注射1∶1 000雌孕激素混合液0.1 mL)。建模后6 h处死大鼠,观察肺组织病理改变,测定肺湿重/干重比值、肺系数,肺组织匀浆中α-ENaC mRNA及蛋白的表达及血清BNP、TNF-α的表达。结果:与对照组比较,模型组出现明显肺水肿、出血及炎性细胞浸润,肺湿重/干重比值、肺系数及血清中BNP、TNF-α表达增加,而α-ENaC mRNA及蛋白明显降低(P<0.01);雌孕激素联合组与ALI模型组比较,肺水肿、出血及炎性细胞浸润要轻,肺湿重/干重比值、肺系数、BNP下降,α-ENaC mRNA及蛋白增加(P<0.05)。结论:雌孕激素联合治疗可上调α-ENaC mRNA及蛋白的表达,减少BNP表达,促进肺泡内液体的清除,为ALI/急性呼吸窘迫综合症(ARDS)的治疗和监控提供新的方法。  相似文献   
82.
大鼠胰腺炎相关性急性肺损伤模型的探讨   总被引:3,自引:0,他引:3  
目的研究5%牛磺胆酸钠(TAC)逆行胆胰管注射诱发急性胰腺炎相关肺损伤的大鼠模型。方法采用改进的胆胰管逆行注射TAC造成大鼠急性出血坏死型胰腺炎(AHNP)模型,将大鼠随机分为3组:AHNP组、假手术组、地塞米松(DXM)治疗组。造模成功后,立即静脉注射大剂量DXM(5 mg/kg)。术后于3、6、12 h处死,留取外周血测定血清淀粉酶、脂肪酶,取右肺中叶测定肺湿干比值及作病理切片,计算等级评分评价肺损伤;行支气管肺泡灌洗,以灌洗液白蛋白与血清白蛋白含量比值计算肺指数。结果AHNP组36、、12 h肺通透性指数、湿干比值及病理学评分逐渐增加,经单因素方差分析,61、2 h组高于3 h组(P<0.05),前两者于6、12 h组组内比较差异不显著(P>0.05)。DXM组于术后61、2 h,各项肺损伤指标均低于AHNP组(P<0.05)。结论TAC胆胰管逆行注射造成AHNP模型大鼠于术后6 h即出现明显的肺损伤表现,符合PALI病理改变,与临床AHNP合并急性肺损伤(ALI)的病理过程相似,可于此时相点作为研究AHNP合并肺损伤的模型。  相似文献   
83.
Explanations for the effects of the rapid eye movements induced during Eye Movement Desensitization Reprocessing (EMDR; Shapiro, 2001) have drawn upon an analogy with the eye movements of REM sleep (Kuiken, Bears, Miall, and Smith, 2002). An extension of that analogy posits two orienting systems, one involving threat-fear related mnemonic contextualization and another involving loss-pain related monitoring of conflicting response alternatives. In a study involving individuals who had recently experienced significant loss or trauma, we found that experimentally induced saccadic eye movements decreased reaction times to unexpected stimuli among those reporting traumatic distress (characterized by hyperarousal and intrusive thoughts) and increased reaction times among those reporting separation distress (characterized by vivid reminiscences and the sense of a foreshortened future). Also, we found that saccadic eye movements increased the perceived strikingness of metaphoric sentence endings among those reporting amnesia for events related to either loss or trauma. The eye movements of both EMDR and REM sleep may differently affect the attentional and cognitive reorienting activity of those living with the consequences of loss or trauma. These differences may be evident in their waking reflections and in their dreams. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
84.
The American Psychiatric Association's recent inclusion of a Glossary of Culture-Bound Syndromes within DSM-IV draws upon decades of medical anthropological and cultural psychiatric research to afford culture-bound syndromes (CBSs) a newfound legitimacy within professional Western psychiatric nosology. While DSM-IV's recognition of the CBS concept as a category of psychosocial distress has important clinical implications for mental health care practitioners throughout the world, it also has significant legal implications. Given that several CBSs involve a degree of psychological impairment that may satisfy the standard for legal insanity under certain circumstances, this essay focuses on the potential emergence of an insanity defense based on the claim that an immigrant or minority defendant was suffering from a CBS at the time of his or her criminal act. Aimed at initiating interdisciplinary debate over the reification of the CBS concept, the essay discusses the theoretical ambiguity and status of CBSs within professional Western psychiatry, describes what a CBS-based insanity defense might look like, and considers the relevant challenges facing medical anthropologists and cultural psychiatrists, on the one hand, and legal practitioners, on the other. The essay identifies a pressing need for interdisciplinary debate concerning the validity, scope, and viability of CBS-based insanity defenses.  相似文献   
85.
Sound production during reproductive behaviour, dyadic encounters and distress situations was investigated in the callichthyid catfish Corydoras paleatus. Sounds were broad-band, pulsed, acoustic signals produced during abduction of the pectoral spines. Only males emitted trains of sounds during courting and trains of sounds of shorter duration during dyadic encounters. Several males, which are usually smaller than females, courted one gravid female without obvious cooperation or competition between them. During mating, one previously vocalizing male clasped the female's barbels with one pectoral spine and inseminated the eggs. The number of successful spawnings, days until spawning, and number of eggs laid was not related to the number of males (one, two or three) combined with one female. Males did not behave aggressively towards each other during courting or in dyadic encounters. In distress situations, when fish were hand held, both sexes and juveniles produced single sounds. The dominant frequency was negatively correlated with body size and the sound duration was positively correlated with relative length of pectoral spines (standardized to body length). This acoustical behaviour in C. paleatus differs considerably from Hoplosternum thoracatum, a representative of the callichthyine subfamily, in which vocalization was observed during territorial behaviour in males and aggressive behaviour in both sexes. This is the first report of a major difference in vocalizing behaviour within one teleost family.  相似文献   
86.
Infant lesser bushbabies are typically able, from the earliest age, to utter distress vocalizations which appear to have major adaptive significance. Distress vocalizations of infant G. moholi were analyzed by means of a digital storage oscilloscope. Three kinds of sound analyses were carried out: analysis of the sound wave signal, sequential spectrum analysis, and fast Fourier transformation. We emphasize analysis of the frequency spectrum. Three distress calls were identified-the click call, the crackle, and the chirp-which we report for the first time. Click calls were typically composed of short, high-pitched pulses (clicks) uttered in fast, repetitive sequences with a broad band frequency spectrum containing frequencies up to 60 kHz. These acoustic characteristics appear to be particularly well suited for accurate spatial localization of the sound source. The main function of the click call is apparently to alert and to guide the mother to a lost or endangered infant. These basic acoustic characteristics-related to sound localization-are shared to some extent, with the other two distress calls. However, the three calls appear to represent different degrees of distress, with the click call being the basic, call, the crackle corresponding to a greater degree of distress, and the chirp possibly signaling extreme distress such as physical pain.We prefer the specific name,Galago moholi (A. Smith, 1836), for the southern African lesser bushbaby [instead ofGalago senegalensis moholi (A. Smith, 1839)] according to the new classification proposed by Olson (1979, 1986) and Nashet al. (1989).  相似文献   
87.
Several conceptual and methodological challenges must be solved in order to create knowledge that can be useful to pregnant women, their families, and any clinicians who serve them: (1) going beyond nominal and ordinal hypotheses and presenting estimates of conditional probabilities; (2) focusing on clearly defined outcomes; (3) modeling the relationship of fetal growth and length of gestation; (4) understanding the process of fetal growth even though most of our data is cross-sectional; (5) estimating the independent effects of genetics, race, ethnicity, maternal risk behaviors, medical prenatal care, and socioeconomic status on fetal growth and length of gestation; and (6) estimating the independent effects of maternal pre-pregnancy weight, weight gain during pregnancy, and nutrition on fetal growth and length of gestation. The analysis and writing of this study was funded, in part, by a grant from the National Institute of Child Health and Human Development (NICHD RO1 HD 20511). Troy D. Abell, Ph.D., M.P.H., is associate professor of anthropology and adjunct associate professor of family medicine at the University of Oklahoma. His major interests are in the biocultural determinants of fetal growth and the epistemologic issues inherent in statistical reasoning, scientific inference, and decision analysis.  相似文献   
88.
摘要 目的:探讨肺表面活性物质(PS)治疗新生儿呼吸窘迫综合征(NRDS)前给予经鼻持续气道正压通气(nCPAP)呼吸支持的最佳时间窗。方法:选择2017年1月至2019年12月期间我院收治的NRDS患儿100例。根据随机数字表法分为A组(给予PS前预先进行小于2 h的nCPAP,n=33)、B组(给予PS前预先进行2-4 h的nCPAP,n=33)和C组(立即给予PS,n=34)。对比三组患儿的血气分析指标、肺功能指标、临床指标和并发症发生率。结果:A组、B组给予PS后4h、给予PS后24 h动脉血氧分压(PaO2)、pH值高于C组,且B组高于A组(P<0.05),而动脉二氧化碳分压(PaCO2)低于C组,且B组低于A组(P<0.05)。A组、B组给予PS后4 h、给予PS后24 h潮气量(VT)、肺动态顺应性(CD)高于C组,且B组高于A组(P<0.05),而吸气阻力(Raw)低于C组,且B组低于A组(P<0.05)。B组用药后3天内需气管插管行机械通气例数少于A组和C组,住院时间短于A组和C组(P<0.05),A组、C组的用药后3天内需气管插管行机械通气例数、住院时间对比无明显差异(P>0.05)。三组患儿并发症发生率未见统计学差异(P>0.05)。结论:给予PS前预先进行2-4h的nCPAP,可较好地改善患儿血气分析指标和肺功能,有助于改善患儿预后。  相似文献   
89.
摘要 目的:探讨脓毒症相关急性呼吸窘迫综合征(ARDS)患者血清乳酸(Lac)、D-二聚体(D-D)、可溶性血栓调节蛋白(sTM)、内皮细胞特异性分子-1(ESM-1)的表达及其临床意义。方法:选取2020年1月~2022年1月徐州医科大学附属医院重症医学科收治的375例脓毒症相关ARDS患者,根据入院时氧合指数(OI)差异分为轻度组(n=96)、中度组(n=152)和重度组(n=127),比较各组血清Lac、D-D、sTM、ESM-1水平,采用Spearman相关系数分析血清Lac、D-D、sTM、ESM-1与OI的相关性。根据28d内预后将患者分为死亡组(n=137)和存活组(n=238),收集临床资料,采用多因素Logistic回归分析脓毒症相关ARDS患者预后的影响因素。采用受试者工作特征(ROC)曲线分析血清Lac、D-D、sTM、ESM-1对脓毒症相关ARDS患者预后不良的预测价值。结果:轻度组、中度组、重度组血清Lac、D-D、sTM、ESM-1水平依次升高(P<0.05)。Spearman相关性分析结果显示:脓毒症相关ARDS患者的血清Lac、D-D、sTM、ESM-1水平与OI均呈负相关(P<0.05)。死亡组年龄大于存活组,脓毒性休克、ICU停留时间≥10 d、机械通气时间≥3 d比例以及SOFA评分、血清Lac、D-D、sTM、ESM-1水平均高于存活组,OI低于存活组(P<0.05)。多因素Logistic回归分析显示:脓毒性休克、SOFA评分≥13分、血清Lac、D-D、sTM、ESM-1水平较高是脓毒症相关ARDS患者预后不良的危险因素,而OI较高是预后不良的保护因素(P<0.05)。ROC曲线分析结果显示:血清Lac、D-D、sTM、ESM-1联合检测预测脓毒症相关ARDS患者预后不良的AUC为0.907,明显高于各指标单独检测的0.785、0.747、0.796、0.789。结论:血清Lac、D-D、sTM、ESM-1水平升高与脓毒症相关ARDS病情严重程度和预后不良密切相关,对患者预后有一定预测价值。  相似文献   
90.
Fetal intolerance of labor is a common indication for delivery by Caesarean section. Diagnosis is based on the presence of category III fetal heart rate tracing, which is an abnormal heart tracing associated with increased likelihood of fetal hypoxia and metabolic acidemia. This study analyzed data from 177 unique women who, during their prenatal visits (7-15 weeks and/or 24–32 weeks) to Atlanta area prenatal care clinics, consented to provide blood samples for DNA methylation (HumanMethylation450 BeadChip) and gene expression (Human HT-12 v4 Expression BeadChip) analyses. We focused on 57 women aged 18–36 (mean 25.4), who had DNA methylation data available from their second prenatal visit. DNA methylation patterns at CpG sites across the genome were interrogated for associations with fetal intolerance of labor. Four CpG sites (P value <8.9 × 10?9, FDR <0.05) in gene SLC9B1, a Na+/H+ exchanger, were associated with fetal intolerance of labor. DNA methylation and gene expression were negatively associated when examined longitudinally during pregnancy using a linear mixed-effects model. Positive predictive values of methylation of these four sites ranged from 0.80 to 0.89, while negative predictive values ranged from 0.91 to 0.92. The four CpG sites were also associated with fetal intolerance of labor in an independent cohort (the Johns Hopkins Prospective PPD cohort). Therefore, fetal intolerance of labor could be accurately predicted from maternal blood samples obtained between 24–32 weeks gestation. Fetal intolerance of labor may be accurately predicted from maternal blood samples obtained between 24–32 weeks gestation by assessing DNA methylation patterns of SLC9B1. The identification of pregnant women at elevated risk for fetal intolerance of labor may allow for the development of targeted treatments or management plans.  相似文献   
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