加强学科建设与人才培养再创百年辉煌

医院的学科建设与人才培养是每个医院在面对日益激烈的医疗竞争环境中必须思考和解决的问题.文章着重阐述了医学学科建设与人才培养二者之间的关系,并结合医院实际,对如何进行医学学科建设与人才培养作了探讨.     

灯盏花素大鼠在体肠吸收动力学研究

目的 研究灯盏花素在大鼠肠道的吸收动力学。方法 进行大鼠在体肠循环灌流肠吸收实验，HPLC法测定灯盏花乙素，研究灯盏花素在小肠和结肠的吸收情况，并分别考察不同质量浓度和不同pH对小肠吸收的影响。结果胆管结扎与胆管不结扎的实验组之间，吸收速率常数（ka）和吸收百分率均有显著性差异，在小肠和结肠的ka分别为（0．1071±0．013O）和（0．0707±0．0089）h^-1；灯盏花素在不同质量浓度下，未发现饱和现象，其ka几乎保持不变，在pH6．0～7．4，灯盏花素的吸收不受pH的影响。结论 灯盏花素在小肠的吸收多于在结肠的吸收，其吸收机制为被动扩散，吸收过程为一级动力学过程，提示灯盏花素可以被制成口服缓释剂型。     

大鼠长期服苯妥英锌或苯妥英钠对体内锌铜代谢的影响

本文用原子吸收分光光度法测定了大鼠分别服用苯妥英锌和苯妥英钠13周后(每天剂量为12mg/kg体重),肝脏、全脑、齿龈和血清锌铜的含量。苯妥英锌使齿龈和肝脏锌分别增高80％和49％,全脑和血清锌分别降低39％和35％,而苯妥英钠使齿龈和肝脏锌分别降低70％和28％,血清锌增高41％。两药均使全脑和齿龈铜降低。     

Sulfate Freeze–Thaw Resistance of Magnesium Potassium Phosphate Cement Mortar

Concrete facilities in the severe-cold areas of western China (salt lake environments and heavy saline soils) are seriously damaged by the multiple corrosion effects of freeze–thaw cycles and sulfate corrosion. Magnesium phosphate cement (MPC) cement-based material has become an ideal concrete structural component because of its superior performance. Because concrete structural repair materials are used in heavy-corrosion environments, their durability in those environments should also be considered. Regarding the salt-freezing resistance of MPC, the existing studies have all used a NaCl solution as the heat transfer medium. In addition to chlorine salt, sulfate, especially Na₂SO₄, is also common in typical use environments such as oceans, salt lakes, and groundwater. To evaluate the sulfate freeze–thaw resistance of potassium magnesium phosphate cement (MKPC) mortar, in this study the strength development, weight loss, and water absorption of MKPC mortar specimens subjected to different freeze–thaw cycles were tested and compared with those for Portland cement (P.O) mortar specimens of the same strength grade. The results showed that the P.O mortar specimen completely lost its strength after 75 cycles of rapid water freezing and thawing and 50 cycles of sodium sulfate solution (5%) freezing and thawing. However, the residual strength rating of the MKPC mortar specimen after 75 cycles of water freezing and thawing and 100 cycles of sodium sulfate solution freezing and thawing was higher than 75%. After 50 rapid freeze–thaw cycles in water and a 5% Na₂SO₄ solution, the P.O mortar specimen’s mass loss exceeded the 5% failure standard, whereas the mass loss of the MKPC mortar specimens was much less than 5%. Before the freeze–thaw cycles, the water absorption of the P.O mortar specimen was close to 8 times that of the MKPC mortar specimen, and after 50 water freeze–thaw cycles and 25 sulfate solution freeze–thaw cycles, the water absorption reached 4.88% and 5.68%, respectively. However, after 225 freeze–thaw cycles in water and the sulfate solution, the water absorption rates of MKPC mortar specimens were 2.91% and 2.51% respectively. The test and analysis results show that the freeze–thaw resistance of MKPC mortar was much higher than that of Portland cement mortar specimens. Those results provide a prerequisite for applying and expanding the use of MKPC-based materials in severe-cold areas of western China (salt lake and heavily saline soil environments).     

Drop Weight Impact Test on Prepacked Aggregate Fibrous Concrete—An Experimental Study

In recent years, prepacked aggregate fibrous concrete (PAFC) is a new composite that has earned immense popularity and attracted researchers globally. The preparation procedure consists of two steps: the coarse aggregate is initially piled into a mold to create a natural skeleton and then filled with flowable grout. In this instance, the skeleton was completely filled with grout and bonded into an integrated body due to cement hydration, yielding a solid concrete material. In this research, experimental tests were performed to introduce five simple alterations to the ACI 544 drop weight impact test setup, intending to decrease result dispersion. The first alteration was replacing the steel ball with a steel bar to apply a line impact instead of a single point impact. The second and third introduced line and cross notched specimens at the specimen’s top surface and the load applied through a steel plate of cross knife-like or line load types. These modifications distributed impact load over a broader area and decrease dispersion of results. The fourth and fifth were bedding with sand and coarse aggregate as an alternate to the solid base plate. One-hundred-and-eight cylindrical specimens were prepared and tested in 12 groups to evaluate the suggested alteration methods. Steel and polypropylene fibers were utilized with a dosage of 2.4% to produce PAFC. The findings indicated that the line notched specimens and sand bedding significantly decreased the coefficient of variation (COV) of the test results suggesting some alterations. Using a cross-line notched specimen and line of impact with coarse bedding also effectively reduced COV for all mixtures.     

Quantification of the Hardened Cement Paste Content in Fine Recycled Concrete Aggregates by Means of Salicylic Acid Dissolution

Adherent hardened cement paste attached to recycled concrete aggregates (RCA) generally presents a higher porosity than natural aggregates, which induces a lower porosity in the properties of RCA. The characterization of the adherent hardened cement paste content (HCPC) in the fine RCA would promote better applications of RCA in concrete, but the determination of HCPC in fine RCA is not well established. A simple method based on salicylic acid dissolution was specifically developed to quantify the HCPC in RCA, especially for RCA containing limestone aggregates. The results demonstrated that the soluble fraction in salicylic acid (SFSA) was equal to the HCPC for white cement and slightly lower for grey Portland cement, which was also confirmed by a theoretical approach using modelling the hydration of cement paste with the chemical equations and the stoichiometric ratios. The physical and mechanical properties of RCA (e.g., water absorption) were strongly correlated to the SFSA. For industrial RCA, SFSA did not give the exact value of HCPC, but it was sufficient to correlate HCPC with the other properties of RCA. The water absorption could be estimated with good accuracy for very fine RCA (laboratory-manufactured RCA or industrial RCA) by extrapolating the relationship between water absorption and HCPC, which is very important for concrete formulation.     

Acoustic Performance of Sound Absorbing Materials Produced from Wool of Local Mountain Sheep

Wool of mountain sheep, treated nowadays as a waste or troublesome byproduct of sheep husbandry, was used for the production of sound-absorbing materials. Felts of two different thicknesses were produced from loose fibres. Additionally, two types of yarn, ring spun and core rug, were obtained. The yarns were used for the production of tufted fabric with cut and loop piles. During the examinations, basic parameters of the obtained materials were determined. Then, according to standard procedure with the use of impedance tube, the sound absorption coefficient was measured, and the noise reduction coefficient (NRC) was calculated. It was revealed that felt produced from coarse wool exhibits high porosity, and its sound absorbing capacity is strongly related to the felt thickness. For thicker felt the NRC achieved 0.4, which is comparable with the NRC of commercial ceiling tiles. It was shown that the crucial parameter influencing the sound absorption of the tufted fabrics was the pile height. For both types of yarns, when the height of the pile was increased from 12 to 16 mm, the NRC increased from 0.4 to 0.42. The manufactured materials made from local wool possess good absorption capacity, similar to commercial products usually made from more expensive wool types. The materials look nice and can be used for noise reduction as inner acoustic screens, panels, or carpets.     

康复科护理人员对残疾人态度、工作成就感与人性化护理能力的关系

目的 了解康复科护理人员人性化护理能力的现状,并探讨其与对残疾人的态度和工作成就感间的关系。方法 2020年12月至2021年3月,便利抽取锦州市、盘锦市、营口市和抚顺市8所综合性三甲医院的196例康复科护理人员,采用医护人员对残疾人态度量表、工作成就感量表、护士人性化护理能力量表进行调查。结果 康复科护理人员人性化护理能力总分为(73.39±10.75),总条目均分(3.86±0.57);康复科护理人员人性化护理能力与对残疾人态度和工作成就感均呈正相关(r=0.208～0.774, P <0.01);工作成就感在康复科护理人员对残疾人态度和人性化护理能力间起部分中介作用,中介效应为0.420,占总效应的52.83%。结论 康复科护理人员人性化护理能力较差。对残疾人态度越好,工作成就感越高,人性化护理能力会越强。康复科护理人员对残疾人态度不仅可以直接作用于人性化护理能力,也可以通过工作成就感间接影响人性化护理能力。     

恢复儿科本科招生缓解儿科医生短缺现状

  目的  分析中国儿科医生工作满意度现状及影响因素,探讨儿科医生短缺原因并提出对策。  方法  2018年8 — 12月,在全国范围内进行多阶段分层随机抽样,共抽取4 906名儿科医生进行工作满意度调查,并运用单因素方差分析与多因素logistic回归分析进行统计分析。  结果  有效调查4 198人,儿科医生总体工作满意度平均得分为（3.06 ± 0.613）分,工作本身与社会支持平均得分为（3.37 ± 0.650）分,工作内容与回报平均得分为（2.32 ± 0.733）分,领导与人际关系平均得分为（3.06 ± 0.771）分。单因素分析结果显示,年龄、性别、地区、医疗机构等级、专业职称等级、任职年限、管床数（工作量）、周休息天数、月收入分组工作满意度得分差异均有统计学意义（P < 0.05）。多因素logistic回归分析显示,任职年限 ≥ 1年是儿科医生工作满意度的危险因素,女性、周休息天数1～2 d、月收入 ≥ 10 000元是儿科医生工作满意度的保护因素。  结论  中国儿科医生的工作满意度较低,月收入、周休息天数、性别、工作年限等是影响其工作满意度的主要因素。