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81.
Kazuyuki Enomoto Shuichi Takahashi Yasunari Maekawa 《Macromolecular chemistry and physics.》2012,213(1):72-78
Most polymer grafts in grafted polymer films obtained by radiation‐induced solid graft polymerization are not analyzed in detail due to difficulties in isolation of the grafts without structural decomposition. Herein, a novel structural and molecular weight characterization method is reported for polymer grafts that are chemically attached to thermally and chemically stable polymer substrates, based on a swelling‐induced graft detachment in hot water. Polymer grafts prepared by the radiation‐induced polymerization of alkyl acrylate into poly(ethylene‐co‐tetrafluoroethylene) (ETFE) followed by a sulfonation reaction are found to have a ternary copolymer structure whose monomer units contain –COOH or –SO3H groups, or both. 相似文献
82.
83.
《Placenta》2016
IntroductionFetal membranes (FM) usually fail prior to delivery during term labor, but occasionally fail at preterm gestation, precipitating preterm birth. To understand the FM biomechanical properties underlying these events, study of the baseline in-vivo stretch experienced by the FM is required. This study's objective was to utilize high resolution MRI imaging to determine in-vivo FM stretch.MethodsEight pregnant women (38.4 ± 0.4wks) underwent abdominal-pelvic MRI prior to (2.88 ± 0.83d) caesarean delivery. Software was utilized to determine the total FM in-vivo surface area (SA) and that of its components: placental disc and reflected FM. At delivery, the SA of the disc and FM in the relaxed state were measured. In-vivo (stretched) to delivered SA ratios were calculated. FM fragments were then biaxially stretched to determine the force required to re-stretch the FM back to in-vivo SA.ResultsTotal FM SA, in-vivo vs delivered, was 2135.51 ± 108.47 cm2 vs 842.59 ± 35.86 cm2; reflected FM was 1778.42 ± 107.39 cm2 vs 545.41 ± 22.90 cm2, and disc was 357.10 ± 28.08 cm2 vs 297.18 ± 22.14 cm2. The ratio (in-vivo to in-vitro SA) of reflected FM was 3.26 ± 0.11 and disc was 1.22 ± 0.10. Reflected FM re-stretched to in-vivo SA generated a tension of 72.26 N/m, corresponding to approximate pressure of 15.4 mmHg. FM rupture occurred at 295.08 ± 31.73 N/m corresponding to approximate pressure of 34 mmHg. Physiological SA was 70% of that at rupture.DiscussionFM are significantly distended in-vivo. FM collagen fibers were rapidly recruited once loaded and functioned near the failure state during in-vitro testing, suggesting that, in-vivo, minimal additional (beyond physiological) stretch may facilitate rapid, catastrophic failure. 相似文献
84.
S. Córdoba-Vives I.J. Rivera-Chavarría 《Clínica e investigación en ginecología y obstetricia》2021,48(4):100682
Placenta accreta spectrum is an abnormal placentation that results in an increase in maternal morbidity and mortality, which mostly occurs due to severe haemorrhage. We present the case of a patient diagnosed prenatally with placenta accreta spectrum, premature rupture of membranes and bleeding, who was managed by a multidisciplinary team. Temporary bilateral hypogastric balloon occlusion was placed before caesarean hysterectomy, with good results for the mother. 相似文献
85.
目的分析胎膜早破者胎盘病理改变情况,探讨其与妊娠结局之间的关系。方法在我院入住孕妇中选取213例胎膜早破者作为观察组,同时选取无胎膜早破的正常孕妇200例为对照组。采用常规HE染色对两组孕妇胎盘形态学进行观察,分析胎盘病理变化与妊娠结局的关系。结果两组中胎盘病理改变包括胎盘胎膜感染、合体细胞结节增多、间质血管增多、纤维化蛋白沉积、胎盘钙化等。其中观察组中各病理变化的发生所占比例与对照组比较明显升高,差异均具有统计学意义(P<0.05);对照组中新生儿感染、产褥感染、胎儿窘迫等妊娠结局的发生率明显低于观察组,差异具有统计学意义(P<0.05),对照组中新生儿窒息的发生率与观察组比较差异无统计学意义(P>0.05)。结论胎膜早破者胎盘病理改变与妊娠结局有密切关系,通过对胎盘病理改变的监测,对防治不良妊娠结局具有重要的指导意义。 相似文献
86.
《Vaccine》2021,39(30):4126-4134
ObjectiveTo pave the way for universal or risk factor-based vaccination strategies, the present study aimed to describe the epidemiology and compare risk factors for hospitalization associated with respiratory syncytial virus (RSV) and influenza virus infections in Danish children.MethodsNational register-based cohort study among 403,422 Danish children born 2010–2016.ResultsPrior asthma hospitalization, number of children in the household, chronic disease and maternal history of asthma hospitalization were the most important risk factors for both RSV and influenza hospitalization. The incidence of influenza increased at school start.ConclusionsOur findings enable targeted vaccination programs for high-risk children with asthma-like disease, chronic disease, siblings in the household, or maternal history of asthma hospitalization. 相似文献
87.
《Immunobiology》2021,226(6):152151
Resolvin D1 (RvD1), which is biosynthesized from essential long-chain fatty acids, is involved in anti-inflammatory activity and modulation of T cell response. Memory CD8+ T cells are important for controlling tumor growth and viral infections. Exacerbated inflammation has been described as impairing memory CD8+ T cell differentiation. This study aimed to verify the effects of RvD1 on memory CD8+ T cells in vitro and in vivo in a respiratory virus infection model. Peripheral blood mononuclear cells were treated at different time points with RvD1 and stimulated with anti-CD3/anti-CD28 antibodies. Pre-treatment with RvD1 increases the expansion of memory CD8+ T cells. The IL-12 level, a cytokine described to control memory CD8+ T cells, was reduced with RvD1 pre-treatment. When the mTOR axis was inhibited, the IL-12 levels were restored. In a respiratory virus infection model, Balb/c mice were treated with RvD1 before infection or after 7 days after infection. RvD1 treatment after infection increased the frequency of memory CD8+ T cells in the lung expressing II4, II10, and Ifng. During reinfection, RvD1-treated and RSV-infected mice present a high viral load in the lung and lower antibody response in the serum. Our results show that RvD1 modulates the expansion and phenotype of memory CD8+ T cells but contributed to a non-protective response after RSV reinfection. 相似文献
88.
Sava Papazov Kostadin Brandiski Ivan Daskalov 《Journal of medical engineering & technology》2013,37(1):28-33
Transthoracic defibrillation is a procedure applying high intensity electrical current through the thorax region by electrodes, in order to simultaneously activate most of the myocardial cells, thus enforcing them to reinstate a normal rhythm. A solution is proposed for analysis and synthesis of the current density distribution field J in the heart region. In an attempt to reach uniform excitation of the greatest possible quantity of myocardial cells, a field image is searched for, with the J-vector uniformity distribution as a criterion. The finite element method and the method of approximating functions are used, as well as nonlinear programming. This approach resulted in designing a two-layer defibrillation electrode, with the layer applied to the thorax divided in three different resistivity regions. 相似文献
89.
90.
《Gynécologie, obstétrique & fertilité》2014,42(2):78-83
ObjectivesTo update knowledge on placental abruption because there are few recent series published although the perinatal care has progressed.Patients and methodsA retrospective observational study has been conducted on 100 consecutive cases of abruptio placentae, occurring from January 2008 to June 2011, in the two maternity units of the University Hospital of Strasbourg (France).ResultsOne hundred and five births among which five twin pregnancies were included. Clinical context was evident in 91% of cases, but the classic clinical triad was present in only 4% of cases. Clots were found at immediate placenta examination in 77% of cases. Pathological diagnosis was directly in accordance with clinical diagnosis in half the cases. Mean date of childbirth was 33 weeks of amenorrhea and 6 days. Sixty-seven patients gave birth prematurely. Among them, 50 patients delivered before 34 weeks. Sixty caesareans were performed in emergency before labor, including 47 with general anesthesia. Twelve patients had post-partum haemorrhage and ten coagulation disorders. There was no maternal death. Perinatal mortality was 19% with 13 fetal deaths in utero (12.4%), four children born in an apparent death state with resuscitation failure (3.8%) and three neonatal deaths (2.8%).Discussion and conclusionPlacental abruption is a serious and unpredictable situation. Joint medical care of obstetricians and intensivists is often required. Perinatal mortality mainly occurs in utero. 相似文献