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101.
The Fourier transform infrared (FTIR) spectra of blood plasma and blood cells from two control female mice and four bred female mice were obtained using the blood component sample films formed on polyethylene IR cards. The protein level in each component was found to remain relatively constant for the control mice. Spectral differences due to variations in protein contents, however, were observed for the pregnant mice. The results show that the FTIR‐IR card method can be simple and effective at probing total blood protein changes.  相似文献   
102.
简要总结了工程强度理论的发展和现况,指出存在的问题,然后提出了作者经30年研究而创立并发展的双剪强度理论和统一强度理论.统一强度理论,一方面建立起现有各种强度理论之间的联系;同时也使以往各种只能适用于某一类材料的单一强度理论发展为可以适用于众多材料的统一强度理论;可以广泛适用于从金属到岩石、混凝土、土体等各类材料。最后通过二个实例,说明统一理论的应用。  相似文献   
103.
We present an exact algorithmic framework, so-called BFC-MSMIP, for optimizing multistage stochastic mixed 0–1 problems with complete recourse. The uncertainty is represented by using a scenario tree and lies anywhere in the model. The problem is modeled by a splitting variable representation of the Deterministic Equivalent Model of the stochastic problem, where the 0–1 variables and the continuous variables appear at any stage. The approach uses the Twin Node Family concept within the algorithmic framework, so-called Branch-and-Fix Coordination, for satisfying the nonanticipativity constraints in the 0–1 variables. Some blocks of additional strategies are used in order to show the performance of the proposed approach. The blocks are related to the scenario clustering, the starting branching and the branching order strategies, among others. Some computational experience is reported. It shows that the new approach obtains the optimal solution in all instances under consideration.   相似文献   
104.
妊娠期高血压疾病(以下简称妊高病)是妊娠期特有的疾病.随着生活节奏快、精神压力大、高龄初产妇增多等高危因素的凸现,妊高病倾向者也逐渐增多.目前,对妊高病发病高危因素的研究很多.本文基于双重logistic回归模型对影响妊高病的危险因素进行变量选择和预测分析.  相似文献   
105.
A numerical method is proposed for solving singularly perturbed turning point problems exhibiting twin boundary layers based on the reproducing kernel method (RKM). The original problem is reduced to two boundary layers problems and a regular domain problem. The regular domain problem is solved by using the RKM. Two boundary layers problems are treated by combining the method of stretching variable and the RKM. The boundary conditions at transition points are obtained by using the continuity of the approximate solution and its first derivatives at these points. Two numerical examples are provided to illustrate the effectiveness of the present method. The results compared with other methods show that the present method can provide very accurate approximate solutions.  相似文献   
106.
The design of a portable Raman/SERS‐LFA reader with line illumination using a custom‐made fiber optic probe for rapid, quantitative, and ultrasensitive point‐of‐care testing (POCT) is presented. The pregnancy hormone human chorionic gonadotropin (hCG) is detectable in clinical samples within only 2–5 s down to approximately 1.6 mIU mL?1. This acquisition time is several orders of magnitude shorter than those of existing approaches requiring expensive Raman instrumentation, and the method is 15‐times more sensitive than a commercially available lateral flow assay (LFA) as the gold standard. The SERS‐LFA technology paves the way for affordable, quantitative, and ultrasensitive POCT with multiplexing potential in real‐world applications, ranging from clinical chemistry to food and environmental analysis as well as drug and biowarfare agent testing.  相似文献   
107.
The placenta is an important organ that maintains a healthy pregnancy by transporting nutrients to the fetus and removing waste from the fetus. It also acts as a barrier to protect the fetus from hazardous materials. Recent studies have indicated that nanoparticles (NPs) can cross the placental barrier and pose a health risk to the developing fetus. The high production and widespread application of copper oxide (CuO) NPs may lead to higher exposure to humans, raising concerns of health hazards, especially in vulnerable life stages, e.g., pregnancy. Oxidative stress plays a crucial role in the pathogenesis of adverse pregnancy outcomes. Due to its strong antioxidant activity, dietary curcumin can act as a therapeutic agent for adverse pregnancy. There is limited knowledge on the hazardous effects of CuO NPs during pregnancy and their mitigation by curcumin. This study aimed to investigate the preventive effect of curcumin against CuO NP-induced toxicity in human placental (BeWo) cells. CuO NPs were synthesized by a facile hydrothermal process and characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and photoluminescence techniques. We observed that curcumin did not induce toxicity in BeWo cells (1–100 µg/mL for 24 h), whereas CuO NPs decreased the cell viability dose-dependently (5–200 µg/mL for 24 h). Interestingly, CuO NP-induced cytotoxicity was effectively mitigated by curcumin co-exposure. The apoptosis data also exhibited that CuO NPs modulate the expression of several genes (p53, bax, bcl-2, casp3, and casp9), the activity of enzymes (caspase-3 and -9), and mitochondrial membrane potential loss, which was successfully reverted by co-treatment with curcumin. The mechanistic study suggested that CuO-induced reactive oxygen species generation, lipid peroxidation, and higher levels of hydrogen peroxide were significantly alleviated by curcumin co-exposure. Moreover, glutathione depletion and the lower activity of antioxidant enzymes (superoxide dismutase, glutathione peroxidase, and catalase) were effectively mitigated by curcumin. We believe this is the first report exhibiting that CuO-induced toxicity in BeWo cells can be effectively alleviated by curcumin. The pharmacological potential of dietary curcumin in NP-induced toxicity during pregnancy warrants further investigation.  相似文献   
108.
《Physics letters. A》2020,384(1):126036
In lung cancer, primary diagnosis is quite essential to guarantee human health. In this work, the capability of γ-graphyne and twin-graphene sheets to detect typical breath gases such as benzene, styrene, aniline, and o-toluidine is studied based on density functional theory. The results indicate that these gases are physisorbed on γ-graphyne and twin-graphene. Because of relatively low gas binding strength between gases and γ-graphyne and twin-graphene, these sheets can be proper for the practical gas sensors with a fast recovery rate. Both γ-graphyne and twin-graphene have semiconducting properties before and after gas adsorption. Adsorption of the gases decreases the energy band gap, and increases the electric dipole moment of γ-graphyne and twin-graphene. The electronic properties of twin-graphene are more sensitive than that of γ-graphyne to the presence of the considered gases. Hence, twin-graphene can be desirable and promising material for sensing typical breath gases to diagnose lung cancer.  相似文献   
109.
探讨磁共振成像(MRI)定量参数、血β-人绒毛膜促性腺激素(β-HCG)与瘢痕妊娠清宫术后再治疗关系及临床意义。选取303例行B超引导下清宫术治疗的剖宫产瘢痕妊娠患者进行回顾性研究,根据术后是否再次入院治疗分为再治疗组、未再治疗组。比较两组瘢痕厚度、胚胎大小、血β-HCG,采用Logistic回归方程、受试者操作特征(ROC)曲线及ROC曲线下面积(AUC)处理分析数据。结果显示,再治疗组瘢痕厚度低于未再治疗组,胚胎大小、血β-HCG高于未再治疗组(P<0.05);瘢痕厚度、胚胎大小、血β-HCG均与再治疗独立相关(P<0.05)。瘢痕厚度、胚胎大小、血β-HCG预测再治疗的AUC值分别为0.734、0.811、0.819,三者联合的AUC值为0.902。因此,联合检测瘢痕厚度、胚胎大小、血β-HCG可预测剖宫产瘢痕妊娠B超引导下清宫术后再治疗的概率。  相似文献   
110.
目的研究分析个体化孕期营养管理对胎儿体质量和产后出血的影响。方法研究对象选择吉安市妇幼保健院2015年12月—2016年7月进行定期产检的146例孕妇,将其随机分成研究组和对照组,每组73例。对照组孕妇给予常规体检以及注意事项讲述;实验组孕妇则在对照组基础上给予个体化孕期营养管理。结果研究组2 500~3 500 g新生儿体质量明显的高于对照组,数据差异显著具有统计学意义(P0.05);研究组剖宫产率、产后出血率、巨大儿发生率分别为20.55%、3.27%、2.74%,对照组分别为36.98%、16.44%、19.18%,数据差异显著具有统计学意义(P0.05)。研究组孕妇蛋白质、钙、铁等指标摄入量以及RDA均明显高于对照组,数据差异显著具有统计学意义(P0.05)。结论个体化孕期营养管理能够有效地将胎儿体质量控制在正常范围之内,同时还能降低孕产妇产后出血情况,临床效果显著,值得推广使用。  相似文献   
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