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排序方式： 共有187条查询结果，搜索用时 15 毫秒
1.
The boxes contained kiwifruits were irradiated with cobalt-60 γ-rays at different dosages (0.6 , 1.8 and 3.6 KGy) and stored in a room ventilated at night, the natural ambient air being used as cool source.The results showed that the treatment which fruits irradiated with 0.6 KGy was the best after 85 days. It gave the normal-fruit rate of 95.10%, fruit flesh hardness of 4.10 Kg · cm-2, fresh and plump fruits, good quality and less Vc loss. 相似文献
2.
报道了2886名正常儿童与718例反复呼吸道感染儿童头发中微量元素含量对比研究结果。研究表明,患儿的身高、体重和发Zn明显低于正常儿童,而发Cu、Ca、Pb则明显高于正常和童。因子提取分析显示,Zn和Pb在儿童反复呼吸道感染发病中起非常重要的作用。患反复呼吸道感染儿童约占儿童总数的20％左右。 相似文献
3.
反复上呼吸道感染患儿发样微量元素锌,铜,铁检测结果分析 总被引：1，自引：0，他引：1
采用示波极谱法对１８３名反复上呼吸道感染患儿及１１８名健康体检儿同时进行发样锌，铁，铜测定，结果表明，反复上呼吸道感染儿发锌，铁均低于健康体检儿，有高度显著性差异，铜只在婴儿组反复感儿高于健康体检儿，其它各年龄组反复上感儿低于健康栓检儿或无显著性差异，说明以２儿童进行常规发样微量元素普查，发现低锌，低铁者及时给予补充，可减少感染性疾病的发生率。铜与免疫功能的关系尚待研究。 相似文献
4.
The full resolution of flows involving particles whose scale is hundreds or thousands of times smaller than the size of the flow domain is a challenging problem. A naive approach would require a tremendous number of degrees of freedom in order to bridge the gap between the two spatial scales involved. The approach used in the present study employs two grids whose grid size fits the two different scales involved, one of them (the micro‐scale grid) being embedded into the other (the macro‐scale grid). Then resolving first the larger scale on the macro‐scale grid, we transfer the so obtained data to the boundary of the micro‐scale grid and solve the smaller size problem. Since the particle is moving throughout the macro‐scale domain, the micro‐scale grid is fixed at the centroid of the moving particle and therefore moves with it. In this study we combine such an approach with a fictitious domain formulation of the problem resulting in a very efficient algorithm that is also easy to implement in an existing CFD code. We validate the method against existing experimental data for a sedimenting sphere, as well as analytical results for motion of an inertia‐less ellipsoid in a shear flow. Finally, we apply the method to the flow of a high aspect ratio ellipsoid in a model of a human lung airway bifurcation. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
5.
Giuseppe C. Pappalardo Eugenio Tondello 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):5-10
Abstract The total energy, dipole moment and electron densities for each possible rotational conformation about the Cpy-S bonds of di-2-pyridyl disulfide were evaluated by using the semi-quantitative CNDO/2 method. The conformations in which the pyridine rings are coplanar with the valency plane of the bonded sulfur atom (cis-cis, cis-trans and trans-trans) were predicted to be the most favored ones. Results of the theoretical study, when compared to some experimental determinations such as dipole moment and variable temperature pmr spectra, provided evidence that easy interconversion between these conformations can occur. 相似文献
6.
Ivan Lazic Riccardo Pernice Tatjana Loncar-Turukalo Gorana Mijatovic Luca Faes 《Entropy (Basel, Switzerland)》2021,23(6)
Apnea and other breathing-related disorders have been linked to the development of hypertension or impairments of the cardiovascular, cognitive or metabolic systems. The combined assessment of multiple physiological signals acquired during sleep is of fundamental importance for providing additional insights about breathing disorder events and the associated impairments. In this work, we apply information-theoretic measures to describe the joint dynamics of cardiorespiratory physiological processes in a large group of patients reporting repeated episodes of hypopneas, apneas (central, obstructive, mixed) and respiratory effort related arousals (RERAs). We analyze the heart period as the target process and the airflow amplitude as the driver, computing the predictive information, the information storage, the information transfer, the internal information and the cross information, using a fuzzy kernel entropy estimator. The analyses were performed comparing the information measures among segments during, immediately before and after the respiratory event and with control segments. Results highlight a general tendency to decrease of predictive information and information storage of heart period, as well as of cross information and information transfer from respiration to heart period, during the breathing disordered events. The information-theoretic measures also vary according to the breathing disorder, and significant changes of information transfer can be detected during RERAs, suggesting that the latter could represent a risk factor for developing cardiovascular diseases. These findings reflect the impact of different sleep breathing disorders on respiratory sinus arrhythmia, suggesting overall higher complexity of the cardiac dynamics and weaker cardiorespiratory interactions which may have physiological and clinical relevance. 相似文献
7.
《印度化学会志》2021,98(12):100250
Within this work, two novel Cu(II) and Mn(II)-based coordination polymers (CPs) along with chemical compositions of {[Cu2(L1)(1,4-NDC)2]·3H2O}n (1, 1,4-H2NDC = Naphthalene-1,4-dicarboxylic acid, L1 = di(1H-imidazole-1-yl)methane) and [Mn3(L2)2(H2O)2(1,4-NDC)2]n (2, L2 = 1,4-di(1H-imidazole-1-yl)benzene) have been completed in success via related metal salts reaction with 1,4-H2NDC ligand in existence of various N-donor co-ligands. We discovered its application values on the surgical site infections (SSI) along with corresponding mechanism in the interim. We evaluated inflammatory cytokines released into the urine through ELISA detection kit after compound treatment. Then, we discovered the inhibitory effect of compound on the bacterial biofilm formation via real time RT-PCR. 相似文献
8.
Julien Antih Marketa Houdkova Klara Urbanova Ladislav Kokoska 《Molecules (Basel, Switzerland)》2021,26(21)
While the inhalation of Thymus vulgaris L. essential oil (EO) is commonly approved for the treatment of mild respiratory infections, there is still a lack of data regarding the antimicrobial activity and chemical composition of its vapours. The antibacterial activity of the three T. vulgaris EOs against respiratory pathogens, including Haemophilus influenzae, Staphylococcus aureus, and Streptococcus pyogenes, was assessed in both liquid and vapour phases using the broth microdilution volatilisation (BMV) method. With the aim of optimising a protocol for the characterisation of EO vapours, their chemical profiles were determined using two headspace sampling techniques coupled with GC/MS: solid-phase microextraction (HS-SPME) and syringe headspace sampling technique (HS-GTS). All EO sample vapours exhibited antibacterial activity with minimum inhibitory concentrations (MIC) ranging from 512 to 1024 μg/mL. According to the sampling technique used, results showed a different distribution of volatile compounds. Notably, thymol was found in lower amounts in the headspace—peak percentage areas below 5.27% (HS-SPME) and 0.60% (HS-GTS)—than in EOs (max. 48.65%), suggesting that its antimicrobial effect is higher in vapour. Furthermore, both headspace sampling techniques were proved to be complementary for the analysis of EO vapours, whereas HS-SPME yielded more accurate qualitative results and HS-GTS proved a better technique for quantitative analysis. 相似文献
9.
小儿反复呼吸道感染与微量元素 总被引：11，自引：0，他引：11
刘秀夫 《广东微量元素科学》2005,12(7):39-42
小儿反复呼吸道感染与微量元素的关系已引起临床的广泛重视.观点较一致的是缺锌、缺铁、铜异常、铅过高对机体有显著影响.小儿呼吸道的生理解剖的特点以及免疫机制未完善,微量元素的异常影响了小儿免疫机制和机体各系统的正常功能,导致小儿反复呼吸道感染. 相似文献
10.
检测了240例反复呼吸道感染患儿血微量元素含量。结果表明,反复呼吸道感染患儿血锌、铁、钙低于正常对照组(P<0.01);血铅高于正常对照组(P<0.01);血铜、镁两组相当,差异不显著(P<0.05)。提示反复呼吸道感染患儿体内存在锌、铁、钙元素缺乏及铅含量升高。 相似文献