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21.
支原体培养基中真菌抑菌剂的筛选   总被引:1,自引:0,他引:1  
目的 为支原体的培养基筛选一种抗真菌的药物,以防止真菌污染。方法 在五种备选药物中先找出不抑制支原体生长但是能够有效抑制真菌生长的药物。再选用20株白色念珠菌的临床株,各测此种药物对其MIC,最后得出MIC50与MIC90,选用MIC90的浓度加于支原体的培养基中。结果 最后选出的药物为氟康唑,用20临床株测得MIC50为15.6μg/ml,MIC90为31.25μg/ml结论选用浓度为31.25μg/ml的氟康唑加于支原体的培养基可以有效抑制白色念珠菌的生长。  相似文献   
22.
The medium carbon-medium alloy steel was developed for the manufacture of large ball mill liners and sports equipment. In this study, the continuous cooling transformation curve of a novel type of medium carbon-medium alloy steel was measured with a thermal simulation machine; based on this curve, the hardening and tempering processes were optimized. The steel was then complex modified with alkaline earth and rare earth alloys. The mechanical properties of the treated steel were tested. The microstructure of the steel was analyzed by metallographic microscopy, X-ray diffraction, scanning electron microscopy and transmission electron microscopy, and the wear surface of the steel was analyzed by a three-dimensional morphometer. After high-temperature tempering, the microstructure transformed into tempered sorbite, which possesses good mechanical properties and can adapt to working conditions that require high strength and toughness. Rare earth or alkaline earth modification of the medium carbon-medium alloy steel promoted microstructural uniformity and grain refinement and improved the mechanical and anti-wear properties.  相似文献   
23.
Arachidonic acid (AA) metabolites control cell proliferation, among other physiologic functions. RAW 264.7 macrophages can metabolise AA through the cyclooxygenase and lipoxygenase (LOX) pathways. We aimed to study the role of AA-metabolites derived from 5-LOX in the control of RAW 264.7 macrophage growth. Our results show that zileuton, a specific 5-LOX inhibitor, and nordihydroguaiaretic acid (NDGA), a non-specific LOX inhibitor, inhibit cell proliferation and [(3)H]-thymidine incorporation in a concentration-dependent fashion. Growth inhibition induced by NDGA can be explained by an apoptotic process, while zileuton does not seem to induce apoptosis. Moreover, these treatments delay the cell cycle, as analysed by flow cytometry. On the other hand, the leukotriene (LT) B(4) receptor antagonist U-75302, the LTD(4) receptor antagonists LY-171883 and MK-571, and the cysteinyl-LT receptor antagonist REV-5901 also inhibit cell proliferation and [(3)H]-thymidine incorporation in a concentration-dependent manner, and delay the RAW 264.7 cell cycle. However, these antagonists did not induce annexin V staining, caspase activation or DNA fragmentation. Furthermore, we demonstrated that exogenous addition of LTB(4) or LTD(4) revert the cell growth inhibition induced by zileuton or the leukotriene receptor antagonists mentioned above. Finally, we observed that LTB(4) and LTD(4), in the absence of growth factors, have pro-proliferative effects on macrophages, and we obtained preliminary evidences that this effect could be through mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI3K) pathways. In conclusion, our results show that the interaction between LTB(4) and LTD(4) with its respective receptor is involved in the control of RAW 264.7 macrophage growth.  相似文献   
24.
25.
Stress myocardial perfusion imaging (MPI) is the preferred test in patients with intermediate-to-high clinical likelihood of coronary artery disease (CAD) and can be used as a gatekeeper to avoid unnecessary revascularization. Cardiac magnetic resonance (CMR) has a number of favorable characteristics, including: (1) high spatial resolution that can delineate subendocardial ischemia; (2) comprehensive assessment of morphology, global and regional cardiac functions, tissue characterization, and coronary artery stenosis; and (3) no radiation exposure to patients. According to meta-analysis studies, the diagnostic accuracy of perfusion CMR is comparable to positron emission tomography (PET) and perfusion CT, and is better than single-photon emission CT (SPECT) when fractional flow reserve (FFR) is used as a reference standard. In addition, stress CMR has an excellent prognostic value. One meta-analysis study demonstrated the annual event rate of cardiovascular death or non-fatal myocardial infarction was 4.9% and 0.8%, respectively, in patients with positive and negative stress CMR. Quantitative assessment of perfusion CMR not only allows the objective evaluation of regional ischemia but also provides insights into the pathophysiology of microvascular disease and diffuse subclinical atherosclerosis. For accurate quantification of myocardial perfusion, saturation correction of arterial input function is important. There are two major approaches for saturation correction, one is a dual-bolus method and the other is a dual-sequence method. Absolute quantitative mapping with myocardial perfusion CMR has good accuracy in detecting coronary microvascular dysfunction. Flow measurement in the coronary sinus (CS) with phase contrast cine CMR is an alternative approach to quantify global coronary flow reserve (CFR). The measurement of global CFR by quantitative analysis of perfusion CMR or flow measurement in the CS permits assessment of microvascular disease and diffuse subclinical atherosclerosis, which may provide improved prediction of future event risk in patients with suspected or known CAD. Multi-institutional studies to validate the diagnostic and prognostic values of quantitative perfusion CMR approaches are required.  相似文献   
26.
目的 改变传统的胆道造影方法 ,采用滴注造影剂进行胆道造影 ,以达到胆道最佳造影。方法 常规消毒T管 ,用 9号Y形穿刺针穿刺入T管 ,缓慢滴入 38%泛影葡胺以显影胆道。结果  96例胆道显影良好 ,其中 3例提示总胆管下端残余结石 ,拔T管后经窦道胆镜下取石成功 ,2例为气体所致假结石阴影 ,经生理盐水冲洗后再造影即消失。结论 低流量滴注造影剂能较理想显影胆道 ,并容易发现结石 ,而且方法简单 ,对病人刺激轻微 ,不失为一种胆道造影的好方法  相似文献   
27.
医院宣传通常采取大众传播和人际传播两种方式。由于大众传播具有广泛性、及时性、高效性和较强的渗透性等特点,得到了医院管理者的普遍重视。而"走出去""迎进来"和"自造新闻"三种宣传策略,将有助于医院利用大众传播扩大知名度、打造特色品牌。  相似文献   
28.
Environmental pollution has particular implications for the whole geosystem and increases the global risk to human and ecological health. In this regard, investigations were carried out on soil samples to perform the quality status assessment by determining: pH, texture, structure and metal concentration, as well as carrying out an assessment of anthropogenic activity by determining pollution indices: Cf (contamination factor), Cd (degree of contamination), PLI (pollution load index), Er (ecological risk index) and PERI (potential ecological risk index). Analyses on soil samples showed high concentrations of metals (Cu: 113–2996 mg kg−1; Pb: 665–5466 mg kg−1; Cr: 40–187 mg kg−1; Ni: 221–1708 mg kg−1). The metal extraction experiments were carried out by bioleaching using Thiobacillus ferrooxidans, microorganisms at different amounts of bioleaching solution (20 mL and 40 mL 9K medium) and a stirring time of up to 12 h. The results on the degree of contamination, pollution loading index PLI (2.03–57.23) and potential ecological risk index PERI (165–2298) indicate that the soils in the studied area have a very high degree of pollution. The decontamination procedure by bioleaching showed a decrease, but at the end of the test (12 h), the followed indices indicate high values, suggesting that bioleaching should continue. The depollution yield after 12 h of treatment is, however, encouraging: Cu 29–76%, Pb: 10–32%, Cr: 39–72% and Ni 44–68%. The use of yield–time correlation equations allows the identification of the optimal exposure time on the bioleaching extraction process to obtain optimal results. The aim of the research is to determine the soil quality, soil environmental risk, extraction of metals from polluted soils by bioleaching and to identify influencing factors in achieving high remediation yields.  相似文献   
29.
Spark Plasma Sintering (SPS) has become a conventional and promising sintering method for powder consolidation. This study aims to well understand the mechanisms of densification encountered during SPS treatments, especially in the early stages of sintering. The direct current (DC) electrical behavior of copper granular medium is characterized. Their properties are correlated with their microstructural evolutions through post-mortem scanning electron microscope (SEM) observations to allow a thorough understanding of the involved Branly effect that is suspected to occur in SPS. The electrical response is studied by modifying the initial thickness of the oxide layer on particles surfaces and applying various mechanical loads on the granular medium. Without load and at low current, the measured quasi-reversible behavior is connected to the formation of spots at the microcontacts between the particles. By increasing the current, the Branly transition from an insulating to a conductive state suddenly occurs. The insulating oxide layer is destroyed, and micro-bridges are created. The application of a mechanical pressure strongly modifies the DC Branly effect. Increasing low stress leads to a strong decrease in the breakdown field. For high-applied pressure, successive drops in the electric field are detected during the electrical transition. These successive drops are induced by microcracking of the insulating oxide layer.  相似文献   
30.
目的:观察自体胸腔积液上清作为培养液对肿瘤浸润淋巴细胞(TIL)生长的影响.方法:恶性胸腔积液中的TIL经贴壁法分离后,分别采用含有细胞因子白细胞介素-2(IL-2)、CD3单克隆抗体(OKT3)及植物血球凝集素(PHA)的自体胸腔积液上清及含10%人AB型血清的RPMIl640进行培养,比较两种培养液对TIL的增殖速度、培养前后免疫表型变化和对自体肿瘤细胞的杀伤活性。结果:培养2周,经统计学比较发现,自体胸腔积液上清作为培养液对TIL的生长速度、免疫表型和对自体肿瘤细胞杀伤活性的影响与应用含10%人AB型血清的RPMIl640培养液培养无差异。结论:自体胸腔积液上清作为培养液培养TIL是可行的。为自体TIL疗法治疗恶性胸腔积液提供理论基础。  相似文献   
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