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81.
《中国现代医生》2020,58(2):119-122
目的探讨远红外线治疗仪照射在血液透析患者新建动静脉内瘘成熟的影响。方法选取我院2016年3月~2018年3月期间治疗的维持性血液透析并培养动静脉内瘘患者60例作为研究对象,根据单双数将其随机分为研究组(单数)与对照组(双数),各30例,所有患者术后3个月均由同一组护士进行穿刺,首次使用内瘘时间均为50 d,使用内瘘2个月为观察期,在此基础上,对照组患者给予健康教育,同时在2周拆线后采用握力器锻炼手臂肌肉功能,研究组患者于术后3 d采用远红外线治疗仪照射内瘘侧手臂。观察两组患者的治疗情况。结果研究组患者术后第1天内瘘成熟度评分比较差异无统计学意义(P0.05),研究组患者术后40 d、术后110 d内瘘成熟度评分高于对照组,差异有统计学意义(P0.05)。研究组患者血肿、渗血及栓塞等并发症发生率低于对照组,且第1针成功率高于对照组,差异有统计学意义(P0.05)。研究组患者疼痛评分低于对照组,内瘘内径评分高于对照组,差异有统计学意义(P0.05)。结论采用远红外线治疗仪照射能促进血液透析患者新建动静脉内瘘的成熟,以增强治疗效果,提高患者生命质量。  相似文献   
82.
目的:评价杯式法、电解法和红外法3种方法测量塑料薄膜水蒸气透过量的数据一致性。方法:采用厚度均匀的塑料薄膜,经杯式法、电解法和红外法3种方法测量其水蒸气透过量,等效检验评价测定结果的一致性。结果:杯式法、电解法和红外法测量塑料薄膜的水蒸气透过量分别为7.03、7.02和6.99 g/(m2·day)。结论:3种方法的测量结果等效。这为多种方法测量塑料薄膜水蒸气透过量的实验室数据对比提供了一定的数据基础。  相似文献   
83.
天麻是我国名贵的中草药,随着近年来其商品的多样化,掺伪、假冒品不断增多,对其进行更全面、系统的质量控制尤为重要。目前,指纹图谱已成为国际公认的控制中药质量的有效手段之一,主要的研究方法有液相色谱法、薄层色谱法、毛细管电泳色谱、红外光谱、核磁共振、X射线粉末衍射、分子生物学指纹图谱和电化学指纹图谱等,本文对近年来天麻指纹图谱的研究情况进行了归纳总结,为进一步建立该药的质量控制提供了方法和依据。  相似文献   
84.
85.
New important applications of copper metal, e.g., in the areas of hydrogen production, fuel cell operation, and spent nuclear fuel disposal, require accurate knowledge of the physical and chemical properties of stable and metastable copper compounds. Among the copper(I) compounds with oxygen and hydrogen, cuprous oxide Cu(2)O is the only one stable and the best studied. Other such compounds are less known (CuH) or totally unknown (CuOH) due to their instability relative to the oxide. Here we combine quantum-mechanical calculations with experimental studies to search for possible compounds of monovalent copper. Cuprous hydride (CuH) and cuprous hydroxide (CuOH) are proved to exist in solid form. We establish the chemical and physical properties of these compounds, thereby filling the existing gaps in our understanding of hydrogen- and oxygen-related phenomena in Cu metal.  相似文献   
86.

Objective

This study aimed at evaluating the degree of conversion (DC) of four composite resins, being one nanofilled and 3 microhybrid resins, photo-activated with second- and third-generation light-emitting diodes (LEDs).

Material and methods

FiltekTM Z350 nanofilled composite resins and Amelogen® Plus, Vit-l-escenceTM and Opallis microhybrid resins were photo-activated with two second-generation LEDs (Radii-cal and Elipar Free LightTM 2) and one third-generation LED (Ultra-Lume LED 5) by continuous light mode, and a quartz halogen-tungsten bulb (QHT, control). After 24 h of storage, the samples were pulverized into fine powder and 5 mg of each material were mixed with 100 mg of potassium bromide (KBr). After homogenization, they were pressed, which resulted in a pellet that was evaluated using an infrared spectromer (Nexus 470, Thermo Nicolet) equipped with TGS detector using diffuse reflectance (32 scans, resolution of 4 cm-1) coupled to a computer. The percentage of unreacted carbon-carbon double bonds (% C=C) was determined from the ratio of absorbance intensities of aliphatic C=C (peak at 1637 cm-1) against internal standard before and after curing of the specimen: aromatic C-C (peak at 1610 cm-1).

Results

The ANOVA showed a significant effect on the interaction between the light-curing units (LCUs) and the composite resins (p<0.001). The Tukey''s test showed that the nanofilled resin (FiltekTM Z350) and Opallis when photo-activated by the halogen lamp (QTH) had the lowest DC compared with the other microhybrid composite resins. The DC of the nanofilled resin (FiltekTM Z350) was also lower using LEDs. The highest degrees of conversion were obtained using the third-generation LED and one of second-generation LEDs (Elipar Free LightTM 2).

Conclusions

The nanofilled resin showed the lowest DC, and the Vit-l-escenceTM microhybrid composite resin showed the highest DC. Among the LCUs, it was not possible to establish an order, even though the second-generation LED Radii-cal provided the lowest DC.  相似文献   
87.
We calculated the light absorbing potential (LAP) of hemoglobin (Hb) and myoglobin (Mb) in mammalian skeletal muscle at rest based on analysis of published chemical and morphometric data (Part 1), interpreted changes in total[Hb + Mb] from NIRS during exercise (Part 2), and estimated the potential contribution of Hb and Mb to changes in NIRS from rest to exercise (Part 3). Part 1: [Hb] in skeletal muscle was estimated from microvascular volume, systemic blood [Hb], and microvascular hematocrit and saturation at rest and during exercise. Part 2: Changes in total[Hb + Mb] (as t[Hb + Mb]) during cycling or knee extension exercise were interpreted using the results of Part 1. Part 3: Using estimates of mean microvascular PO2, Hb and Mb contribution at peak exercise was estimated. Across several species, [Mb] contributed ∼50–70% of the total LAP to NIRS at rest in skeletal muscle. With exercise, increases in t[Hb + Mb] of up to 30% could be entirely explained by the predicted increase in microvascular hematocrit with exercise. Finally, Mb was estimated to contribute ∼70% of the changes in NIRS from rest to peak exercise.  相似文献   
88.
目的:分析湖北地区泌尿系结石化学成分的构成,为本地区结石的防治提供依据。方法:采用结石红外光谱自动分析系统对2011年11月~2012年8月期间收集到的湖北地区泌尿系结石232例进行成分分析。结果:232例结石中,各成分的检出率为:一水草酸钙(COM)85.34%,二水草酸钙(COD)62.93%,碳酸磷灰石(CA)24.14%,无水尿酸(UA)12.93%,二水磷酸氢钙(PH)4.31%,磷酸铵镁(MAP)6.90%,黄嘌呤1.29%,胱氨酸(CYS)1.29%,方解石0.86%,尿酸铵(AU)0.86%。含草酸钙成分结石86.21%,含磷酸钙成分结石28.45%,含磷酸铵镁成分结石6.90%,含尿酸成分结石13.79%,含胱氨酸成分结石1.29%。混合成分结石181例(78.02%),尿路结石发病男性多于女性,男女比例为3.14:1。结论:湖北地区泌尿系结石以混合性结石为主,COM检出率最高,其次为COD。结石成分分析对于结石的防治有重要意义。  相似文献   
89.
Objectives: The purpose of the study was to investigate and characterize the oral lyophilisates containing the pregabalin-acetaminophen drug combination and as xcipients mannitol with microcrystalline cellulose or hydroxypropyl methylcellulose, in order to conclude upon drug-excipient interactions and their stability implications, impact of excipients on drug release and on the physicochemical and mechanical properties of the pharmaceutical formulations.

Methods: The oral tablets were made by using a Christ freeze-dryer alpha 2–4-LSC lyophilizer, and evaluated for stability, drug-excipient compatibility and homogeneity of the prepared pharmaceutical formulations. The formulations were evaluated for in vivo absorption in rabbits by histopathological exams.

Results: FTIR and thermogravimetric analyses, DLS technique, SEM and NIR-CI studies confirmed the compatibility between compounds. From the determined physical and biochemical parameters of the formulations it was established that they are stable, homogeneous, and meet the conditions for orally disintegrating tablets.

Conclusion: In the case of the investigated pharmaceutical formulations the study evidenced the assembling through physical bonds between the excipients and the ‘codrug’ complex, which do not affect the release of the bioactive compounds.  相似文献   

90.
Cardiopulmonary bypass (CPB) in infants is associated with morbidity due to systemic inflammatory response syndrome (SIRS). Strategies to mitigate SIRS include management of perfusion temperature, hemodilution, circuit miniaturization, and biocompatibility. Traditionally, perfusion parameters have been based on body weight. However, intraoperative monitoring of systemic and cerebral metabolic parameters suggest that often, nominal CPB flows may be overestimated. The aim of the study was to assess the safety and efficacy of continuous metabolic monitoring to manage CPB in infants during open‐heart repair. Between December 2013 and October 2014, 31 consecutive neonates, infants, and young children undergoing surgery using normothermic CPB were enrolled. There were 18 male and 13 female infants, aged 1.4 ± 1.7 years, with a mean body weight of 7.8 ± 3.8 kg and body surface area of 0.39 m2. The study was divided into two phases: (i) safety assessment; the first 20 patients were managed according to conventional CPB flows (150 mL/min/kg), except for a 20‐min test during which CPB was adjusted to the minimum flow to maintain MVO2 >70% and rSO2 >45% (group A); (ii) efficacy assessment; the following 11 patients were exclusively managed adjusting flows to maintain MVO2 >70% and rSO2 >45% for the entire duration of CPB (group B). Hemodynamic, metabolic, and clinical variables were compared within and between patient groups. Demographic variables were comparable in the two groups. In group A, the 20‐min test allowed reduction of CPB flows greater than 10%, with no impact on pH, blood gas exchange, and lactate. In group B, metabolic monitoring resulted in no significant variation of endpoint parameters, when compared with group A patients (standard CPB), except for a 10% reduction of nominal flows. There was no mortality and no neurologic morbidity in either group. Morbidity was comparable in the two groups, including: inotropic and/or mechanical circulatory support (8 vs. 1, group A vs. B, P = 0.07), reexploration for bleeding (1 vs. none, P = not significant [NS]), renal failure requiring dialysis (none vs. 1, P = NS), prolonged ventilation (9 vs. 4, P = NS), and sepsis (2 vs. 1, P = NS). The present study shows that normothermic CPB in neonates, infants, and young children can be safely managed exclusively by systemic and cerebral metabolic monitoring. This strategy allows reduction of at least 10% of predicted CPB flows under normothermia and may lay the ground for further tailoring of CPB parameters to individual patient needs.  相似文献   
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