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1.
Although births below 28 completed weeks' of gestation contribute to less than 1% of all preterm births globally, the impact of extreme prematurity (EPT) on neurodevelopmental outcomes across the life-course is disproportionately large. Higher rates and increased severity of neurodevelopmental impairments (NDIs) are reported among extremely preterm infants (EPIs). Cognitive skills, motor skills (manifesting as cerebral palsy) and vision are most commonly affected, with effects pervasive throughout school, adolescence and early adulthood. In addition, poorer academic outcomes and higher rates of psychiatric morbidity are seen among EPTs. Consistent improvements in EPI survival in recent years has not been matched with improvements in neurodevelopmental outcomes, especially for those born at less than 25 gestational weeks. However, over the last 20 years, several national and cross-national cohort studies have helped advance our understanding of extreme prematurity's developmental and life-course consequences. Here we provide an overview of the key findings from 13 multi-centre cohorts measuring neurodevelopmental outcomes and discuss the theoretical and epidemiological perspectives of NDIs in the context of extreme prematurity to guide communication with families and shared care decision-making.  相似文献   
2.
目的:建立黄芪与板蓝根2种根类药材醇沉絮体的分形维数测定方法。方法:分别以黄芪、板蓝根的水提醇沉絮体为研究对象,采用大津算法对醇沉絮体原始显微图像进行二值化处理,运用周长-面积法分别考察沉淀絮体取样体积、稀释倍数、图像放大倍数及图像采集位点数对分形维数的影响。结果:黄芪与板蓝根醇沉絮体均具有分形特征;确定这2个醇沉絮体取样体积在600~800μL,样品稀释至5~20倍,显微图像放大200倍或400倍,选取4个图像采集位点时,能够得到稳定可靠的醇沉絮体分形维数。结论:建立的测定方法稳定可行,可为根类药材醇沉絮体的分形理论研究提供参考。  相似文献   
3.
IntroductionElectrostatic precipitation Pressurized IntraPeritoneal Aerosol Chemotherapy (ePIPAC) has shown superior penetration depth and tissue uptake compared to standard PIPAC. We investigated the feasibility and objective tumor response to ePIPAC with 1 min of precipitation in patients with peritoneal metastasis (PM).Materials and methodsPatients with PM from various abdominal cancers were included in an amendment to the ongoing prospective PIPAC-OPC2 trial. Colorectal and appendiceal PM were treated with oxaliplatin, patients with PM from other primaries were treated with a combination of cisplatin and doxorubicin. Three ePIPAC procedures were planned in each patient including repeated peritoneal biopsies for response evaluation. After emission to the peritoneal cavity, the aerosolized chemotherapeutics were precipitated for 1 min followed by immediate exsufflation and abdominal closure. Histological regression from the first to the third ePIPAC was evaluated according to the Peritoneal Regression Grading Score (PRGS) and compared to data from the PIPAC-OPC1 trial. Complications and toxicities were recorded according to Dindo-Clavien and CTCAE.ResultsSixty-five ePIPAC procedures were performed in 33 patients (median 2, range 1–6). Ten patients were eligible for response evaluation based on biopsies from the first and third ePIPAC procedure. Four patients had disease progression, four patients had regressive disease, and two patients had stable disease according to PRGS. No life threatening adverse reactions and no mortality was observed following ePIPAC.ConclusionOne minute ePIPAC was feasible and safe, but the histological tumor response was insufficient compared to standard PIPAC directed therapy with 30 min passive diffusion time.  相似文献   
4.
Climate change has led to increased frequency, intensity, and duration of extreme heat events with dire consequences for health. These are the deadliest of climate change impacts with preventable mortality from heat-related illnesses and increased threat to safe participation in physical activity and sports. Nurse practitioners can collaborate with community and professional sports health organizations to ensure evidence-based health and safety policies to reduce health-related risks. Adverse consequences on engagement in key health-promoting physical activity and sports may catalyze urgent action to address climate change.  相似文献   
5.
The effects of anisotropic interfacial properties and heterogeneous elasticity on the growth and ripening of plate-like θ′-phase (Al2Cu) in Al-1.69 at.% Cu alloy are studied. Multi-phase-field simulations are conducted and discussed in comparison with aging experiments. The precipitate/matrix interface is considered to be anisotropic in terms of its energy and mobility. We find that the additional incorporation of an anisotropic interfacial mobility in conjunction with the elastic anisotropy result in substantially larger aspect ratios of the precipitates closer to the experimental observations. The anisotropy of the interfacial energy shows comparably small effect on the precipitate’s aspect ratio but changes the interface’s shape at the rim. The effect of the chemo-mechanical coupling, i.e., the composition dependence of the elastic constants, is studied as well. We show that the inverse ripening phenomenon, recently evidenced for δ’ precipitates in Al-Li alloys (Park et al. Sci. Rep. 2019, 9, 3981), does not establish for the θ′ precipitates. This is because of the anisotropic stress fields built around the θ′ precipitates, stemming from the precipitate’s shape and the interaction among different variants of the θ′ precipitate, that disturb the chemo-mechanical effects. These results show that the chemo-mechanical effects on the precipitation ripening strongly depend on the degree of sphericity and elastic isotropy of the precipitate and matrix phases.  相似文献   
6.
耿瑞慧  刘辉  李成  肖立宁  马红亮  王健 《武警医学》2019,30(11):979-982
 目的 了解“魔鬼周”极限训练对武警特战队员身体状况的影响,以便更有效地预防和减少运动损伤,提高体能训练效果。方法 选取79例来自武警某部参加2017年第三季度“魔鬼周” 极限训练的特战队员作为研究对象,分别于“魔鬼周”的第1天及第7天进行相关血液指标的检测,包括睾酮(T)、天门冬氨酸氨基转移酶(AST)、乳酸脱氢酶 (LDH)、肌酸激酶(CK)、肌酸激酶MB型同工酶(CK-MB)、白细胞数目(WBC)、中性粒细胞百分比(N)、淋巴细胞百分比(L)、红细胞数目(RBC)、血红蛋白浓度(HB)、血小板数目(PLT)。应用SPSS 18.0统计软件进行数据处理。结果 参加“魔鬼周”极限训练的武警特战队员训练后的血清AST、LDH、CK、CK-MB分别为(46.15±43.21)U/L、(285.14±62.76)U/L、(505.17±359.73)U/L、(26.42±16.03)U/L,较训练前(19.67±4.05)U/L、(214.38±31.84)U/L、(222.50±116.09)U/L、(15.85±3.02)U/L明显升高,差异有统计学意义(P<0.05),T、WBC、L、RBC、HB、PLT低于训练前[(21.10±5.58)nmol/L、(5.64±1.24)×109/L、(34.53±7.10)%、(4.82±0.34)×1012/L 、(147.20±7.58)g/L、(216.53±45.35)×109/L vs(22.41±5.00)nmol/L、(6.00±1.42)×109/L、(36.01±8.15)%、(4.93±0.35)×1012/L、(150.75±7.30)g/L、(258.96±47.26)×109/L,P<0.05],N训练前后无明显变化[(57.19±7.26)% vs (56.66±8.62)%]。结论 “魔鬼周”极限训练对武警特战队员的生理功能可产生一定的影响,进而可能影响其训练水平。  相似文献   
7.
Laser-assisted high speed milling is a subtractive machining method that employs a laser to thermally soften a difficult-to-cut material’s surface in order to enhance machinability at a high material removal rate with improved surface finish and tool life. However, this machining with high speed leads to high friction between workpiece and tool, and can result in high temperatures, impairing the surface quality. Use of conventional cutting fluid may not effectively control the heat generation. Besides, vegetable-based cutting fluids are invariably a major source of food insecurity of edible oils which is traditionally used as a staple food in many countries. Thus, the primary objective of this study is to experimentally investigate the effects of water-soluble sago starch-based cutting fluid on surface roughness and tool’s flank wear using response surface methodology (RSM) while machining of 316 stainless steel. In order to observe the comparison, the experiments with same machining parameters are conducted with conventional cutting fluid. The prepared water-soluble sago starch based cutting fluid showed excellent cooling and lubricating performance. Therefore, in comparison to the machining using conventional cutting fluid, a decrease of 48.23% in surface roughness and 38.41% in flank wear were noted using presented approach. Furthermore, using the extreme learning machine (ELM), the obtained data is modeled to predict surface roughness and flank wear and showed good agreement between observations and predictions.  相似文献   
8.
The development of methods to reuse large volumes of plastic waste is essential to curb the environmental impact of plastic pollution. Plastic-reinforced cementitious materials (PRCs), such as plastic-reinforced mortar (PRM), may be potential avenues to productively use large quantities of low-value plastic waste. However, poor bonding between the plastic and cement matrix reduces the strength of PRCs, limiting its viable applications. In this study, calcium carbonate biomineralization techniques were applied to coat plastic waste and improved the compressive strength of PRM. Two biomineralization treatments were examined: enzymatically induced calcium carbonate precipitation (EICP) and microbially induced calcium carbonate precipitation (MICP). MICP treatment of polyethylene terephthalate (PET) resulted in PRMs with compressive strengths similar to that of plastic-free mortar and higher than the compressive strengths of PRMs with untreated or EICP-treated PET. Based on the results of this study, MICP was used to treat hard-to-recycle types 3–7 plastic waste. No plastics investigated in this study inhibited the MICP process. PRM samples with 5% MICP-treated polyvinyl chloride (PVC) and mixed type 3–7 plastic had compressive strengths similar to plastic-free mortar. These results indicate that MICP treatment can improve PRM strength and that MICP-treated PRM shows promise as a method to reuse plastic waste.  相似文献   
9.
陈云云  姚文栋  谢先泽  毛超  张钶  诸佳珍 《中草药》2020,51(21):5447-5453
目的 制备pH敏感释药的As2O3脂质体,并进行体外评价。方法 采用薄膜分散法制备含钙离子脂质体,然后用离子沉淀法孵育制备钙砷复合物脂质体(CaAs-LP)。测定CaAs-LP的粒径、Zeta电位及多分散系数(PDI);透射电子显微镜观察脂质体的形态;电感耦合等离子体发射光谱仪测定纳米药物的载药量与包封率;透析袋法考察其体外释药特性。噻唑蓝(MTT)法考察未载药脂质体及CaAs-LP对人源性乳腺癌MCF-7细胞、人源性脑胶质瘤U87细胞和人源性肝癌HepG2细胞的毒性;共聚焦显微镜考察U87细胞对CaAs-LP的摄取效率。结果 制备的CaAs-LP呈规整类球型,粒径约为(117.16±1.94)nm,包封率和载药量分别为(74.31±2.11)%、(8.31±0.13)%。体外释放研究表明,CaAs-LP具有明显的缓释以及pH响应释药特征。未载药的脂质体在MCF-7、U87、HepG2和L02细胞中的生物相容性良好;CaAs-LP抑制肿瘤细胞生长的作用较原药有所上升,半数抑制浓度(IC50)值分别为11.91、4.90、19.41、27.59 μmol/L。细胞摄取研究表明肝癌细胞对脂质体具有良好的摄取。结论 CaAs-LP具备显著的缓释以及pH响应释药的特性,在肿瘤治疗方面具有较好的应用前景。  相似文献   
10.
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