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981.
Neutrophils infiltration/activation following wound induction marks the early inflammatory response in wound repair. However, the role of the infiltrated/activated neutrophils in tissue regeneration/proliferation during wound repair is not well understood. Here, we report that infiltrated/activated neutrophils at wound site release pyruvate kinase M2 (PKM2) by its secretive mechanisms during early stages of wound repair. The released extracellular PKM2 facilitates early wound healing by promoting angiogenesis at wound site. Our studies reveal a new and important molecular linker between the early inflammatory response and proliferation phase in tissue repair process.  相似文献   
982.
983.

Key points

  • Intrauterine growth restriction (IUGR) is associated with short‐ and long‐term detrimental cardiometabolic effects.
  • Mice and rats are commonly used to assess IUGR, but differences in placental and fetal developmental physiology relative to those in humans highlight the need for alternative small animal IUGR models.
  • We developed a guinea pig IUGR model by gradual occlusion of uterine arteries by ameroid constrictor implantation. In this model, reduced uterine blood flow was associated with IUGR, allowing in vivo assessment of fetal growth trajectory and umbilico‐placental vascular function in conscious animals.
  • The intervention induces placental vascular dysfunction and remodelling, as well as altered fetal abdominal growth resulting in an asymmetric IUGR and preserved brain growth.

Abstract

Intra‐uterine growth restriction (IUGR) is associated with short and long‐term metabolic and cardiovascular alterations. Mice and rats have been extensively used to study the effects of IUGR, but there are notable differences in fetal and placental physiology relative to those of humans that argue for alternative animal models. This study proposes that gradual occlusion of uterine arteries from mid‐gestation in pregnant guinea pigs produces a novel model to better assess human IUGR. Fetal biometry and in vivo placental vascular function were followed by sonography and Doppler of control pregnant guinea pigs and sows submitted to surgical placement of ameroid constrictors in both uterine arteries (IUGR) at mid‐gestation (35 days). The ameroid constrictors induced a reduction in the fetal abdominal circumference growth rate (0.205 cm day−1) compared to control (0.241 cm day−1, P < 0.001) without affecting biparietal diameter growth. Umbilical artery pulsatility and resistance indexes at 10 and 20 days after surgery were significantly higher in IUGR animals than controls (P < 0.01). These effects were associated with a decrease in the relative luminal area of placental chorionic arteries (21.3 ± 2.2% vs. 33.2 ± 2.7%, P < 0.01) in IUGR sows at near term. Uterine artery intervention reduced fetal (∼30%), placental (∼20%) and liver (∼50%) weights (P < 0.05), with an increased brain to liver ratio (P < 0.001) relative to the control group. These data demonstrate that the ameroid constrictor implantations in uterine arteries in pregnant guinea pigs lead to placental vascular dysfunction and altered fetal growth that induces asymmetric IUGR.  相似文献   
984.
Cornea disease is the second cause of blindness and keratoplasty is the most commonly performed option for visual rehabilitation of patients with corneal blindness. However, the clinical treatment has been drastically limited due to a severe shortage of high-quality donor corneas. Although collagen film with outstanding biocompatibility has promising application in corneal tissue engineering, the moisturizing properties of collagen-based materials must be further improved to satisfy the requirements of clinical applications. This paper describes a novel collagen-based film with high moisture capacity reinforced by surface grafting of chondroitin sulfate. The collagen-chondroitin sulfate (abbreviated as Col-CS) film was analyzed by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy and its hydrophilic property, moisture retention, optical property, and mechanical performance had been tested. The moisture-retaining capacity is found to be improved with the introduction of chondroitin sulfate, and the Col-CS membrane performs better mechanical properties than the collagen film. Moreover, the modified film proves excellent biocompatibility for the proliferation of human corneal epithelial cells in vitro. This Col-CS film with good moisturizing properties can reduce the risk of xerophthalmia and is expected to increase the implant success rate in clinic patients with corneal defects.  相似文献   
985.
Objective To understand the quality of life (QOL) and its influencing factors in maintenance hemodialysis patients (hemodialysis maintenance, MHD), and to provide theoretical basis for improving QOL of patients. Methods A cross-sectional study was conducted in the blood purification centre in 8 hospitals of Hefei, and patients clinical data were collected. KDQOL-SF self-administered questionnaire was applied to assess the health related quality of life (HRQL) of patients and to analyze the factors influencing the QOL. Results The QOL of MHD patients in Hefei City was better compared with previous similar research results. Generally speaking, gender (male), education degree and household income were positive correlated with QOL scores (P<0.05), and the scores of primary disease of patients with diabetic nephropathy or drugs were lower (P<0.05) in physiological component summary (PCS), mental component summary (MCS), SF-36 and KDTA. Charlson comorbidity index (CCI) was negatively correlated with the MCS scores, PCS scores and SF scores (P<0.05), and patients' occupational and medical insurance had impacts on MCS and KDTA score (P<0.05). Conclusions The QOL of MHD patients are affected by many factors, and the CCI and cultural level are possible independent influencing factors. In addition, gender, household income per capita, primary disease, occupation, medical insurance also have certain influence.  相似文献   
986.
任亚娟  李靖  贺欣 《北京医学》2016,(3):271-273
目的 探讨颅内表皮样囊肿术后迟发出血的临床特点及护理方法.方法 对2002-2012年北京天坛医院行手术治疗的628例颅内表皮样囊肿患者中术后并发迟发出血的31例患者资料进行回顾性分析,分析该并发症的临床特点及其相应的护理措施.结果 颅内表皮样囊肿术后迟发出血发生率为4.9%(31/628),明显高于同期颅内肿瘤切除术后颅内出血的发生率[0.9%(122/13 479),P< 0.001].31例术后迟发出血患者中,男14例,女17例;平均年龄(39岁±20)岁;出血时间发生在术后第5~23天,中位时间为术后第8天.临床表现主要包括颅高压和(或)脑膜刺激征(71.0%),脑疝(16.1%),癫痫(9.7%)以及晕厥(3.2%).11例出现二次出血,二次出血发生率为35.5%(11/31).25例患者康复出院,其中21例恢复满意,另4例神经功能障碍较前加重;其余6例死亡.结论 颅内表皮样囊肿术后并发迟发出血的时间发生在术后第5~23天,且术后1周左右迟发出血比例较大,出血后二次出血发生率高.在此期间,护理人员应提高对该并发症的警惕,争取早发现,早抢救;出血发生后积极有效的护理,对改善患者的预后具有重要的作用.  相似文献   
987.

Background:

There are limited data on longer-term outcomes (>5 years) for patients with unprotected left main coronary artery (ULMCA) disease who underwent percutaneous coronary intervention (PCI) in the drug-eluting stents (DES) era. This study aimed at comparing the long-term (>5 years) outcomes of patients with ULMCA disease underwent PCI with DES and coronary artery bypass grafting (CABG) and the predictors of adverse events.

Methods:

All consecutive patients with ULMCA disease treated with DES implantation versus CABG in our center, between January 2003 and July 2009, were screened for analyzing. A propensity score analysis was carried out to adjust for potential confounding between the two groups.

Results:

Nine hundred and twenty-two patients with ULMCA disease were enrolled for the analyses (DES = 465 vs. CABG = 457). During the median follow-up of 7.1 years (interquartile range 5.3–8.2 years), no difference was found between PCI and CABG in the occurrence of death (P = 0.282) and the composite endpoint of cardiac death, myocardial infarction (MI) and stroke (P = 0.294). Rates of major adverse cardiac and cerebrovascular events were significantly higher in the PCI group (P = 0.014) in large part because of the significantly higher rate of repeat revascularization (P < 0.001). PCI was correlated with the lower occurrence of stroke (P = 0.004). Multivariate analysis showed ejection fraction (EF) (P = 0.012), creatinine (P = 0.016), and prior stroke (P = 0.031) were independent predictors of the composite endpoint of cardiac death, MI, and stroke in the DES group, while age (P = 0.026) and EF (P = 0.002) were independent predictors in the CABG group.

Conclusions:

During a median follow-up of 7.1 years, there was no difference in the rate of death between PCI with DES implantation and CABG in ULMCA lesions in the patient cohort. CABG group was observed to have significantly lower rates of repeat revascularization but higher stroke rates compared with PCI. EF, creatinine, and prior stroke were independent predictors of the composite endpoint of cardiac death, MI, and stroke in the DES group, while age and EF were independent predictors in the CABG group.  相似文献   
988.
高洁  陈任  吴泥亚  马颖  秦侠  胡志 《安徽医学》2016,37(9):1162-1165
目的 了解我国不同艾滋病疫情地区居民艾滋病知识的知晓情况、艾滋病态度以及艾滋病知识来源,为制定城镇居民艾滋病防治策略提供参考依据。方法 在艾滋病流行的高、中、低地区采用随机抽样,以问卷形式在每个地区调查150~200名居民。结果 调查人群的艾滋病整体知晓率为84.77%,低流行地区艾滋病知晓率为91.61%,高流行地区艾滋病知晓率为78.74%,中流行地区艾滋病知晓率为86.03%,3个地区艾滋病知晓率之间差异有统计学意义(χ2=11.33,P=0.003);超过20.00%的居民在假设与艾滋病感染者/病人同桌吃饭、从他们那里购买蔬菜、艾滋病儿童与未感染者儿童在一起上学时,都表示出排斥心理;艾滋病知识获取来源主要是电视(89.06%)、免费宣传资讯(64.84%)和报刊(63.48%)。结论 艾滋病流行的高、中、低地区居民的艾滋病知识知晓率整体水平较高,但高流行地区居民的艾滋病知识知晓率仍相对较低,应加强对局部地区居民艾滋病知识的教育。  相似文献   
989.

目的  探讨通腑解毒汤联合连续性静-静脉血液滤过(CVVH)对急性重症胰腺炎(SAP)患者肿瘤坏死因子-α(TNF-α)、白介素-6(IL-6)的影响及临床疗效。方法  选择发病72 h的SAP患者40例,随机分为对照组和治疗组,每组20例。对照组予以西医常规治疗,治疗组在对照组的基础上加用中药通腑解毒汤联合CVVH治疗。比较两组治疗前及治疗72 h后IL-6和TNF-α的浓度;观察两组治疗前后生命体征、血气、生化指标、急性生理学与慢性健康状况评分系统Ⅱ(APACHE Ⅱ)评分、Ranson评分等指标,判断患者整体病情。结果  治疗72 h后,治疗组IL-6、TNF-α浓度较对照组降低(P <0.01),治疗组较对照组患者发热、呼吸窘迫等症状有不同程度的缓解,血清淀粉酶(AMY)、丙氨酸转氨酶(ALT)、总胆红素(TBIL)、血肌酐(SCr)、尿素氮(BUN)下降(P <0.05),平均动血压(MAP)逐渐上升,氧分压(PaO2)和氧合指数提高,肠麻痹时间、多器官功能障碍综合征发生率下降,平均住院日缩短(P <0.05)。治疗7 d后,治疗组较对照组APACHE Ⅱ评分、Ranson评分降低(P <0.01),住院费用比较差异无统计学意义(P >0.05)。结论  通腑解毒汤联合CVVH治疗SAP能清除部分促炎因子,减轻炎症反应,提高临床疗效,可作为SAP重要的辅助治疗措施之一。

  相似文献   
990.
目的采用弥散张量成像(diffusion tensor imaging,DTI)及基于纤维束追踪的空间统计(track-based spatial statistics,TBSS)观察常规磁共振成像(magnetic resonance imaging,MRI)表现正常的获得性免疫缺陷综合征(acquired immunodeficiency syndrome,AIDS)患者脑白质微结构变化。方法对性别、年龄相匹配的22例常规MRI表现正常的AIDS患者(患者组)及23例健康志愿者(对照组)行DTI检查,采用TBSS分析所有受试者脑白质DTI的各相关参数指标的改变,包括各向异性分数(fractional anisotropy,FA)、平均弥散度(mean diffusivity,MD)、组间轴向弥散(axial diffusivity,AD)值和径向弥散(radial diffusivity,RD)值,进一步提取组间差异有统计学意义脑区的患者组的DTI参数值并与CD4+进行相关性分析。结果与正常对照组相比,患者组多个脑区MD值升高,主要包括胼胝体膝部、胼胝体体部、胼胝体压部、双侧前辐射冠、上辐射冠、后辐射冠、上纵束、左侧内囊前肢、外囊和扣带回(P<0.05,TFCE及FWE校正)。患者组多个脑区AD值升高,主要包括胼胝体膝部、胼胝体体部、胼胝体压部、双侧前辐射冠、上辐射冠、后辐射冠、上纵束、内囊前肢、外囊和扣带回(P<0.05,TFCE及FWE校正)。左侧白质改变多于右侧,胼胝体及双侧前辐射冠是损伤范围较大的脑区。两组各脑区FA值和RD值差异均无统计学意义(P>0.05,TFCE及FWE校正)。与对照组相比,患者组中差异有统计学意义脑区的MD值与患者CD4计数呈负相关(r=-0.435,P=0.043)。结论常规MRI表现正常的AIDS患者大脑多个区域白质微结构损伤,其病理特征可能是轴索异常改变,损伤区域主要涉及记忆、智能、认知控制等相关脑区。DTI和TBSS技术可以敏感地发现常规MRI表现正常的AIDS患者脑损伤白质微观结构变化。  相似文献   
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