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71.
Nine 1,2,5-trisubstituted benzimidazole derivatives were prepared and their structure have been elucidated by IR, NMR spectral data and elemental analyses. Analgesic activity of the compounds prepared was investigated in mice by modified KOSTER test. Anti-inflammatory activity of these compounds was investigated by a carregeenan-induced hind paw edema model in mice. Their antibacterial activities were examined against S. aureus, E. faecalis, E. coli, P. aeruginosa, and antifungal activity against three kinds of yeast-like fungi (C. albicans, C. parapsilosis, C. stellatoidea).  相似文献   
72.
The authors conducted a study of the quantitative content of amino acids in the blood serum of patients with initial and expressed organic neuro-psychic disorders of a vascular genesis and in a group of normals of the same age. In patients with initial organic syndromes the content of cystin-cystein and treonine in the blood serum increased. In patients with expressed organic syndromes the content of cystin-cystein increased, while the content of arginine acid and leicyn-isoleicyn decreased as compared to the control group of elderly people. A comparative study of the two groups of patients with organic psychopathology of a vascular origin demonstrated that in vascular dementia there are more severe changes in the content of amino acids in the blood serum.  相似文献   
73.
The CAMP reaction between Listeria monocytogenes and Rhodococcus equi was studied by a diffusion assay. Listeria monocytogenes displayed identical cooperative haemolytic effect with supernatant cultures of R. equi or with commercial cholesterol oxidase (COX). This result, even with enzymes of different sources (commercial COX is obtained from Pseudomonas spp.) suggests that this enzyme secreted by R. equi has a crucial role in the synergistic haemolytic (CAMP) reaction with L. monocytogenes. The mechanism of the cooperative lytic process between L. monocytogenes and R. equi may represent a different and novel mechanism reaction, in which the COX may not act as a conventional second-step factor, and a reaction different to the direct interaction with the cholesterol of the erythrocyte membrane may be involved.  相似文献   
74.
为制备具有亲水和防污自清洁性能的PVC建筑薄膜,在经低温等离子体改性的PVC薄膜表面涂覆SiO2作为隔离层,然后采用旋涂法将TiO2涂覆于薄膜表面,制备得到PVC/SiO2/TiO2复合膜。利用XRD、FTIR、SEM、EDS等测试手段对复合膜的形貌和结构进行表征,并用接触角测试仪测定了其亲水性能,经紫外光照后,复合膜的接触角由42.2°降为10.9°,结果表明TiO2层的涂覆大大地提高了PVC薄膜的亲水性能。  相似文献   
75.
Heterogeneous boiling on a horizontal plate in stagnant and slowly flowing fluid is simulated using the lattice Boltzmann approach. The bubble departure diameter and release frequency are determined from the simulation results. It is found that the bubble departure diameter is proportional to g?1/2 in a stagnant fluid and the release frequency scales with g3/4, where g is the gravitational acceleration. Simulation results show no dependence between the bubble departure diameter and the static contact angle, but the bubble release frequency increases exponentially with the latter. Considering forced boiling, exponential relation is observed between the bubble departure diameter and the flow driving pressure gradient.  相似文献   
76.
77.
OBJECTIVE: To assess the extent of functional and vocational rehabilitation achieved by elderly inner-city patients sustained on maintenance hemodialysis. DESIGN: Inception cohort study of elderly patients who have end-stage renal disease using a modified Karnofsky rating system. The need for a wheelchair, participation in household activities, and effect of comorbid conditions were noted. Current status was compared with patient's recollection of functional activity level 2 years before commencing maintenance hemodialysis. SETTING: Seven outpatient, hospital-affiliated and private hemodialysis units in Brooklyn, NY. PATIENTS: One hundred four patients aged 65 years or older who were receiving maintenance hemodialysis for at least 6 months. MAIN OUTCOME MEASURES: A score of 76 or greater on a modified Karnofsky scale indicated independent function at a level that permitted participation in activities beyond those mandated by the hemodialysis regimen. A comorbidity score 6 or greater on a newly constructed index correlated with severe debility. Employment status was also recorded. RESULTS: Present functional activity had deteriorated to a modified Karnofsky score of 66 +/- 12.3 (+/- SD) compared with patients' recollection of a mean score of 84 +/- 14.3 (P < .001) 2 years before initiation of hemodialysis. Diabetic patients had a lower score than nondiabetic patients. The mean comorbidity index of the entire study group was 7.8 +/- 2.9 (mean +/- SD). Within the diabetic subset, severe debility constrained 71 patients (68%) to limit all activity to their residence with the exception of travel to and from their dialysis facility. By contrast, 2 years prior to commencing dialytic therapy, 81 diabetic patients (78%) had interests and activities that took them outside their homes (P < .001). Generalized weakness was the most common explanation given for the lack of outside activity by nine patients (9%) who were wheelchair bound. Erythropoietin, though regularly administered to 87 patients (84%) in the study group, was unsuccessful in raising mean hematocrit reading above 0.28 +/- 0.05 (mean +/- SD). CONCLUSIONS: Maintenance hemodialysis does not return inner-city elderly patients to their predialysis level of functioning. Few elderly, diabetic hemodialysis patients conduct any substantive portion of their lives outside their homes. For nondiabetic patients, the modified Karnofsky score of whites (70.4 +/- 11.9) and blacks (66.5 +/- 15.3), though low, was equivalent (P < .4).  相似文献   
78.
Sources of error in the pre-analytical phase of blood gas analysis   总被引:1,自引:0,他引:1  
Analysis of blood gases and blood pH yield important information in many situations of clinical emergencies. We report on a patient in whom pre-analytic errors in blood gas and blood pH measurements resulted in unnecessary further investigations. We therefore studied various pre-analytic sources of error in blood pH and blood gas analysis. Delay in sample processing for more than one hour resulted in an increase of pO2 and pCO2 and a decrease of pH. Excess sodium heparin solution as an anticoagulant (> or = 10% of total volume) led to a significant decrease of pH and pCO2 and to an increase of pO2. Air bubbles (10% of total volume) left in the syringe for 10 min significantly increased pO2. For accurate estimations of pO2, pCO2 and pH, it is necessary to keep the heparin solution below 10% of total volume, to expel all air bubbles from the syringe and to process the blood sample within one hour. Instructions to medical staff on handling blood samples for blood gas analysis should include these possible sources of errors.  相似文献   
79.
Forces acting on spherical bubbles in a subchannel of a rod bundle with triangular rod arrangement (the pitch to diameter ratio is P/D=1.34) have been studied at low bubble Reynolds numbers O(0.1) ? O(1). The bubble motion has been simulated resolving the interface of the bubble by using the lattice Boltzmann method. Steady drag and virtual mass forces have been determined from the simulation results. Based on the simulation data, the relation CD=16.375/ReT could be established between the steady drag coefficient CD and the terminal Reynolds number ReT when the diameter ratio λ=d/D of the bubble d and the channel D is less than 0.2. It is found that the virtual mass coefficient can achieve as high value as 7.2, which is a consequence of strong wall effects. Considering interactions between bubbles, cooperation in the axial direction and hindering in the lateral direction could be observed. We demonstrate that the relation between the terminal velocity of a bubble and that of the suspension follows a Richardson–Zaki like correlation, but the exponent is not only a function of the Eotvos and Morton numbers, but it also depends on the particle configuration.  相似文献   
80.
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