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To examine effects of lung motion on the separation of pleural surfaces during breathing, we modeled the pleural space in two dimensions as a thin layer of fluid separating a stationary elastic solid and a sliding flat solid surface. The undeformed elastic solid contained a series of bumps, to represent tissue surface features, introducing unevenness in fluid layer thickness. We computed the extent of deformation of the solid as a function of sliding velocity, solid elastic modulus, and bump geometry (wavelength and amplitude). For physiological values of the parameters, significant deformation occurs (i.e. bumps are 'flattened') promoting less variation in fluid thickness and decreased fluid shear stress. In addition, deformation is persistent; bumps of sufficient wavelength, once deformed, require a recovery time longer than a typical breath-to-breath interval to return near their undeformed configuration. These results suggest that in the pleural space during normal breathing, separation of pleural surfaces is promoted by the reciprocating sliding of lung and chest wall. 相似文献
3.
目的 观察休克期大面积切痂对严重烧伤大鼠细胞免疫功能的影响,探索改善烧伤后机体免疫功能紊乱的有效方法。方法 将大鼠分成休克期切痂组(A组)、常规切痂组(B组)和正常对照组(C组)。A、B组造成30%TBSAⅢ度烫伤,C组不烫伤。A组伤后第6h、B组伤后第4d切痂,并于伤后第1、5、9d各活杀10只,取材送检,观察其免疫指标的变化。结果 (1)A、B组与C组比较:A、B组烫伤大鼠各时相点CD3^+T细胞变化不大(P〉0.05),但CD4^+T细胞、CD4^+/CD8^+比值明显下降、CD8^+T细胞增高(P〈0.05或P〈0.01)。NK细胞活性明显下降(P〈0.05或P〈0.01),外周血CD25^+T淋巴细胞表达及经活化后脾脏CD25^+T淋巴细胞表达明显下降(P〈0.05或P〈0.01)。(2)A组与B组比较:A组CD4^+T细胞、CD4^+/CD8^+比值明显升高、CD8^+T细胞降低(P〈0.05或P〈0.01),NK细胞活性明显升高(P〈0.05或P〈0.01),外周血CD25^+T淋巴细胞表达及经活化后脾脏CD25^+T淋巴细胞表达均明显升高(P〈0.05或P〈0.01)。结论 (1)大鼠烫伤后细胞免疫状况发生了明显变化。(2)休克期切痂可以改善烫伤大鼠T淋巴细胞亚群分布,提高NK细胞活性,增加外周血CD25^+T淋巴细胞的表达。提高经活化后脾脏CD25^+T淋巴细胞数。从而改善烫伤大鼠伤后机体的细胞免疫功能。 相似文献
4.
M. M. Cohen B. Schei D. Ansara R. Gallop N. Stuckless D. E. Stewart 《Archives of women's mental health》2002,4(3):83-92
Summary
Background: A link between violence and depression has been shown, but not a link between violence and postpartum depression. This study
sought to determine if there is an association between a history of abuse (physical, sexual, emotional as a child or adult)
and postpartum depression (PPD).
Method: 200 postpartum women were recruited from 6 hospitals. At 8–10 weeks postpartum, a telephone interviewer asked women about
physical, emotional or sexual abuse as an adult or child and sociodemographic, obstetrical and personal medical history. PPD
was assessed using the Edinburgh Postnatal Depression Scale (EPDS, score of ≥12). Abuse was determined by the Conflict Tactics
Scale or the Abuse Assessment Screen. Chi-square and logistic regression were used to determine the relationship between violence
and PPD.
Results: 11% of women had EPDS scores of ≥12. Rates of childhood (6.5%), or adult (6.5%) physical abuse; and childhood (13%) or adult
(14%) sexual abuse were reported by respondents. Emotional abuse in the current relationship (29.6%) exceeded that of childhood
abuse (3.5%). Overall 43.2% of respondents had at least one form of abuse. Having a history of depression (OR = 3.3 (95% CI,
1.3–8.7)), panic attack during pregnancy (OR = 5.4 (1.6–19.0)), maternal complications (OR = 5.0 (1.7–15.1)), low social support
(OR = 3.3 (1.3–8.7)) and emotional abuse (OR = 2.8 (1.1–7.4) were associated with PPD.
Conclusion: Emotional abuse but not physical or sexual abuse was found to be associated with PPD. A possible explanation for this relationship
may be that being in an abusive situation puts one at risk for depression and in turn, postpartum depression. 相似文献
5.
目的 调查温州市人民医院2018—2021年妊娠期高血压疾病(hypertensive disorders of pregnancy,HDP)患者妊娠结局,并分析其妊娠结局的相关影响因素,为临床采取对应干预措施、降低不良妊娠结局发生风险提供参考。 方法 选取2018年1月—2021年12月于温州市人民医院分娩的400例HDP患者(单胎妊娠)的临床资料,开展回顾性分析,根据其妊娠结局分为不良妊娠结局组(n=157)与正常妊娠结局组(n=243)。比较两组临床资料,分析HDP患者不良妊娠结局发生的影响因素,构建logistic回归模型方程,并分析logistic回归模型的预测价值。 结果 400例HDP患者中共157例(39.25%)发生不良妊娠结局;单因素分析显示患者年龄、孕前BMI、分娩方式、妊娠期糖尿病(gestational diabetes mellitus,GDM)、负性情绪与不良妊娠结局的发生有关(P<0.05);logistic回归模型显示,年龄≥35岁(OR=23.815,95%CI:10.370~54.655)、孕前BMI≥24.0(OR=16.010,95%CI:6.832~34.620)、阴道分娩(OR=16.336,95%CI:7.325~36.403)、GDM(OR=26.337,95%CI:11.908~58.253)、负性情绪(OR=20.682,95%CI:2.791~54.876)均为HDP患者不良妊娠结局发生的独立危险因素(P<0.05);5个独立危险因素构建logistic回归模型方程为logistic(P)=-4.125+年龄×3.170+孕前BMI×2.773+阴道分娩×2.793+GDM×3.271+负性情绪×3.029;当logistic(P)=4.11,预测HDP患者发生不良妊娠结局的曲线下面积为0.899(95%CI:0.865~0.926),预测敏感度为84.36%,特异度为82.17%;根据设定的评分标准与不良妊娠结局发生情况,可将HDP患者划分为低风险(0~4分)、中风险(5~8分)与高风险(9~12分)。 结论 HDP患者不良妊娠结局发生率较高,年龄、孕前BMI、阴道分娩、GDM、负性情绪均为不良妊娠结局发生的影响因素,构建logistic回归模型可预测不良妊娠结局发生风险,有助于临床制定相关干预措施。 相似文献
6.
王建军 《中国神经肿瘤杂志》2005,3(2):88-91
背景与目的:中枢神经系统疾病冰冻切片诊断的误诊率较其他脏器相对较高,文献报导误诊率在1.6-13.2%,误诊率较高的肿瘤包括脑膜间叶性肿瘤,血管母细胞瘤,淋巴瘤及少枝胶质细胞瘤。本文总结和探讨神经系统病变术中诊断存在的问题,以提高神经系统病变术中诊断的质量。方法:我们回顾性地研究了4年中所进行的135例神经外科术中送检冰冻标本的诊断,并对照相应石蜡标本的诊断结果进行了分析比较。结果:发现冰冻切片诊断错误9例,误诊率为6.67%。误诊病例包括:星形细胞瘤1/73例(误诊率1.4%),室管膜瘤3/4例(误诊率75%),小脑髓母细胞瘤1,5例(误诊率20%),嗅神经母细胞瘤1,2例(误诊率50%),中枢神经细胞瘤1,2例(误诊率50%),脉络丛肿瘤1,2例(误诊率50%),非肿瘤性病变1,9例(误诊率11.1%)。结论:发生在脑室外的室管膜瘤易发生误诊;小脑髓母细胞瘤、嗅神经母细胞瘤等出现滤泡样结构或表现出结节样的结构时可能与转移性低分化癌混淆;脑组织中血管畸形伴血肿形成,由于常并发出现显著的胶质细胞反应而导致肿瘤的诊断。 相似文献
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8.
Rajesh Vedachalam Kumaresan Yamini Rengaraj Venkatesh Narendran Kalpana Chandrashekaran Shivkumar Madhu Shekhar Aravind Haripriya Ravilla Sathya 《Indian journal of ophthalmology》2022,70(6):2153
Purpose:To analyze the reasons for delay in cataract surgery in patients with advanced cataracts during the COVID-19 pandemic.Methods:This was a prospective, cross-sectional, multicenter questionnaire study which included patients with mature cataract, nuclear sclerotic cataract grade IV, and cataracts with best corrected visual acuity (BCVA) <5/60, during the COVID-19 pandemic from December 2020 to April 2021. Reasons for delay in presentation to the hospital were analyzed.Results:One thousand four hundred seventy two patients were recruited with advanced cataracts. Absence of ophthalmic care nearby (44.2%), lack of awareness regarding elective surgeries (42.6%), lack of public transportation (37%), fear of contracting COVID-19 (23.4%), and waiting for outreach camps (20.4%) were found to be the reasons behind the delay in cataract surgery. 53.7% of the patients had worsening of defective vision and 55.3% of them had difficulty in carrying out activities of family living. 30.8% of the patients faced difficulty in commuting and 8.4% of the patients suffered a fall during this pandemic due to worsening of the visual acuity.Conclusion:The lockdown imposed during the pandemic has created a significant backlog of patients who are progressing to advanced cataracts due to lack of ophthalmic care nearby, lack of awareness regarding elective surgeries, lack of public transportation, and no outreach camps. Proactive measures to deal with this backlog are of utmost need to prevent blindness due to cataract. 相似文献
9.
Background and PurposeTo identify sex differences in daytime sleepiness associated with apnea severity and periodic limb movements during sleep (PLMS) in subjects with obstructive sleep apnea (OSA).MethodsThis study used the Epworth Sleepiness Scale (ESS), Beck Depression Inventory (BDI), and Sleep Hygiene Index (SHI) in logistic regression analyses with interaction terms. Severe OSA, excessive daytime sleepiness (EDS), and PLMS were defined as an apnea-hypopnea index of ≥30, an ESS score of ≥11, and a periodic limb movements index of >15, respectively.ResultsThe 1,624 subjects with OSA (males, 79.1%) comprised 45.3%, 38.2%, and 16.4% with severe OSA, EDS, and PLMS, respectively. Multiple logistic regression without interaction terms showed that sex, severe OSA, and PLMS were not significantly associated with EDS. However, significant interactions were noted between sex and severe OSA and PLMS in EDS in both crude and adjusted models (all p values<0.05). In the adjusted model, severe OSA was associated with EDS in males (p=0.009) but not in females. PLMS were more likely to be associated with EDS in females (p=0.013), whereas PLMS were less likely to be associated with EDS in males (p=0.041). The models were adjusted by the BDI score, SHI, and presence of medical comorbidities.ConclusionsThere are significant sex differences in subjective daytime sleepiness in subjects with severe OSA and PLMS. Severe OSA and PLMS may influence daytime sleepiness more in males and females, respectively. 相似文献
10.
孕期贫血会导致各种妊娠不良结局,如早产,出血耐受性降低,产后出血甚至失血性休克,产褥感染,以及新生儿低体重,新生儿死亡等,严重危害母胎健康。我国妊娠期铁缺乏和缺铁性贫血诊治指南建议通过积极监测血红蛋白及血清铁,加强饮食补铁,预防孕期贫血,从而避免不良妊娠结局的发生。 相似文献