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441.
Naciye EI Levent Dandik H. Ayşe Aksoy 《Journal of the American Oil Chemists' Society》1998,75(9):1207-1211
The solvent-free glycerolysis of used sunflower oil catalyzed by acetone powder of Nigella sativa seeds was investigated. The highest partial acylglycerols yield was obtained at 60°C. The glycerolysis reactions, conducted at molar ratios of 1:1, 2:1, and 3:1 of oil to glycerol keeping the acetone powder content at 30% based on oil weight and the temperature at 60°C, approached equilibrium after 2 h. The highest partial acylglycerol content of the products was 66% (1:1 molar ratio) and 60% (2:1 molar ratio). 相似文献
442.
443.
Neuronal properties and topographic organization of the middle suprasylvian gyrus (cortical cytoarchitectonic field 7) were studied in three behaving cats with painlessly fixed heads. Two main neuronal types were found within this field. Type 1 neurons occupied the lateral part of the field and bordered representation of directionally selective neurons of the lateral suprasylvian visual area by vertical retinal meridian. Type 1 neurons had elongated and radially oriented receptive fields located in the lower part of contralateral visual field. Type 1 neurons preferred stimuli moving out or to the centre of gaze at a low or moderate speed, and many of them were depth selective. The responses were enhanced by attention, oriented to the presented stimulus. Medial part of the field 7 along the border with the area V3 was occupied by neurons with not elongated receptive fields (type 2). These neurons preferred moderate and high speeds of motion, and gratings of proper spatial frequency and orientation were effective stimuli for them. Border between representations of type 2 and type 1 neurons coincided with projection of horizontal retinal meridian. At the rostral and caudal borders of the field 7 abrupt changes of neuronal properties took place. Neurons which abutted field 7 anteriorly and posteriorly resembled hypercomplex cells and their small receptive fields were located in the central part of the visual field. Topographical considerations and receptive field properties allowed us to conclude that the medial part of the field 7 (included type 2 neurons) is functionally equivalent to the area V4 in the cortex of primates, while the lateral part (type 1 neurons) may correspond to the area V4T. 相似文献
444.
We studied anticoagulant effects of combined administration of heparin (H) and chitosan sulfate ether (CS) (specific activity 20 UE/mg) in the ratio 1 : 1. CS enhanced anticoagulant activity of heparin in rabbits by a factor of 1.95 +/- 0.15. The intravenous injection of the mixture in a dose of 0.5 mg(H)/kg + 0.5 mg(CS)/kg and heparin injection in a dose of 1mg/kg induced the same effect. Haemorrhagic effect of this mixture was less pronounced compared to heparin, anticoagulant and antithrombotic activities remained the same. The mixture was found to decrease a number of platelets, however, this was also less pronounced compared to heparin. Thus, the use of the mixture CS + H (1 : 1) instead of double heparin dose resulted in the same effect. 相似文献
445.
SV Petrov NA Bubnova AV Marchenko EI Levitina EN Smolina 《Canadian Metallurgical Quarterly》1996,155(5):30-32
An original method of endolymphatic therapy with the stimulation of the lymph outflow was developed and used in 108 patients with peritonitis. The dynamics of intoxication parameters was studied during the endolymphatic therapy, indirect electrochemical oxidation of blood, photochemotherapy and traditional treatment. The method proposed has been found to be most efficient. The method of endolymphatic therapy with the lymph stimulation allowed lethality from peritonitis to be decreased to 7.4%. 相似文献
446.
EI Astashkin ON Smirnov MG Glezer KE Sobolev SV Grachev 《Canadian Metallurgical Quarterly》1998,360(3):409-411
OBJECTIVE: To assess the risk of probe contamination following transvaginal ultrasonography. DESIGN: Prospective cohort study. SETTING: University Infertility Center. PATIENT(S): Women undergoing transvaginal ultrasonography. INTERVENTION(S): One physician obtained 840 consecutive transvaginal ultrasonograms over nine months. Latex condoms were used to cover the probe. Following examination, the condoms were removed and the probe was wiped with a germicidal disposable cloth and left to air dry for 5 minutes. Condoms were filled with water and examined for leaks. MAIN OUTCOME MEASURE(S): Number of perforations and distance from condom tip. RESULT(S): Seventeen (2%) of 840 condoms leaked. The mean distance from the tip to the point of leakage was 10.6 cm +/- 2.8 (mean +/- SD; range, 7-14). Sixty-five percent of the leaks were < or = 10 cm from the tip. In several instances, two leaking condoms were found within a few examinations of each other. No visual contamination of the probe was noted. CONCLUSION(S): Although only 2% of condoms leaked, 65% were at distances that could have led to probe soiling intravaginally. While no body fluids were grossly visible, microscopic contamination was still possible. Since perforations were noted in close, and even consecutive scans, this study underscores the need for routine probe disinfection between examinations. 相似文献
447.
Konstantinos Meletis Sofia Meniades-Meimaroglou Panagiota Markaki 《Food Additives & Contaminants》2007,24(11):1275-1282
A simple analytical method for ochratoxin A (OTA) determination in grapes is described, using aqueous methanolic extraction, an immunoaffinity column clean-up step and high-performance liquid chromatography with fluorescence detection. Mean recovery was 94% (RSD = 4.0%) with a detection limit of 0.4 ng g-1 and quantification limit of 1.20 ng g-1. Repeatability (r) and reproducibility (R) were 1.17 and 1.34, respectively. OTA determinations were applied to 50 grape samples (23 different varieties) originating from representative regions of Greece. Results showed the presence of OTA in 86% of samples tested (n = 50). Traces were found in 56% of samples but OTA was not detectable in 14% of samples. Traces were also found in 4% of red, organically grown samples. The most contaminated were three samples of red grapes, two from Central Greece (2.69 and 1.41 ng g-1), both table and wine-making grapes. The third sample (1.46 ng g-1), originating from the island of Samos, was used only in wine-making. Mean (1.06 ng g-1) and median (0.76 ng g-1) OTA concentrations in red grapes were slightly higher compared to the mean (0.82 ng g-1) and median (0.65 ng g-1) concentrations in white grape samples. The study shows that the potential risk for a person of 60 kg ranged from 0.9 to 9 ng kg-1 bw day-1 and is dependent on the quantity of grapes consumed daily. 相似文献
448.
EI Kalenikova EA Gorodetskaya NV Zacharova AB Shechter OS Medvedev 《Canadian Metallurgical Quarterly》1998,32(4):608-615
The objective of the study was to determine whether angiotensin (Ang) I elimination in lung circulation depends on the degree of myocardial damage with and without early long-term perindopril treatment in a rat model of myocardial injury induced by intracoronary microembolization. Twenty-one days after surgery, steady-state arterial [125I]-Ang I and [125I]-Ang II blood concentrations were measured after high-performance liquid chromatography separation during i.v. infusion of [125I]-Ang I in three groups of male Wistar conscious rats: (a) sham-operated rats receiving saline (sham group, n = 6); (b) rats after coronary microembolization receiving saline (saline group, n = 7); and (c) rats after coronary microembolization receiving perindopril (2 mg/kg/day; from days 2-20 after embolization; perindopril group, n = 6). Ang I clearance and the Ang I-to-Ang II concentration ratio (R) were estimated. The embolization per se resulted in focal fibrosis, appearance of hypertrophic and dystrophic cardiac myocytes, and was accompanied by increased Ang I clearance (1,479 vs. 314 ml/min in sham group), 1.8-fold decreased [125I]-Ang II arterial level, and decreased R (0.5 vs. 1.2 in sham group; p < 0.05). Only Ang I concentrations and R were correlated with number of scars (r = -0.77; p < 0.05; and r = -0.82; p < 0.01, respectively). Captopril bolus (1 mg/kg, i.v.) caused similar reduction in [125I]-Ang II blood concentration in both sham and saline groups, but a significant increase of [125I]-Ang I blood concentration was detected in the sham group only. Thus in rats with coronary microembolization, a higher proportion of Ang I in lung circulation is eliminated by pathways independent of angiotensin-converting enzyme. In the perindopril group, a reduced number of scars (seven vs. 17 per slice in the saline group; p < 0.05), density of dystrophic and hypertrophic cardiac myocytes, and increased content of cell glycogen were observed. It was accompanied by normalized arterial [125I]-Ang I concentration, Ang I clearance, and R; [125I]-Ang II concentration tended to that in sham group. Only in the sham and perindopril groups was there significant correlation between Ang I and Ang II concentrations. The clear relation between number of scars per slice and R (r = -0.83; p < 0.01) was observed in all rats with embolized coronary vessels (saline and perindopril groups together). In conclusion, in this experimental, model Ang I elimination in the lung circulation was directly related to the degree of myocardial damage. Early perindopril treatment prevented maladaptive changes in Ang I processing and led to significant reduction of the undesirable aftereffects of myocardial tissue damage. Our data demonstrate the cardioprotective action of perindopril based on its beneficial influence on the renin-angiotensin system disturbances. 相似文献
449.
A Fassi F Sangalli R Maffi F Colombi EI Mohamed BM Brenner G Remuzzi A Remuzzi 《Canadian Metallurgical Quarterly》1998,9(8):1399-1406
It has been suggested that a reduced number of nephrons may predispose to systemic hypertension and glomerular injury. Compensatory hemodynamic changes, due to a low number of glomeruli, might be responsible for glomerular functional and structural changes. It is difficult to evaluate this hypothesis in humans because of limitations in estimating the number of nephrons in the living kidney. The aim of the present study was to estimate nephron number, single glomerular hemodynamics, and glomerular volume in male and female MWF rats, a strain that spontaneously develops systemic hypertension, proteinuria, and glomerulosclerosis. Male and female Wistar rats were used as controls. At 12 to 14 wk of age, male MWF rats developed proteinuria, whereas female MWF and Wistar rats showed normal urinary protein excretion rate. Glomerular number was significantly reduced in male and female MWF rats (13,690+/-1,489 and 12,855+/-1,781 gl/ kidney, respectively) compared with Wistar rats (26,955+/-2,171 and 27,166+/-1,754 gl/kidney, respectively). The mean number of nephrons per unit of body weight was also lower in MWF males (88+/-10) compared with MWF females (139+/-20) and compared with male and female Wistar animals (142+/-14 and 221+/-22 gl/g body wt). Whole-kidney hemodynamic parameters and the number of nephrons were used to calculate single-nephron filtration rate and plasma flow. Both measures were markedly elevated in male MWF rats relative to values obtained in the other three groups. Similarly, glomerular volume was significantly greater in MWF males than in other animals. These results suggest that an inborn deficit of nephrons may be responsible for spontaneous development of later-in-life hypertension and renal dysfunction. The data also indicate the need to investigate the role of this potential pathogenetic factor for human hypertension and kidney disease in humans. 相似文献
450.
Molecular dynamics calculations have been carried out on a model of the LS3 synthetic ion channel in a membrane mimetic environment. In the absence of an external electrostatic field, the LS3 channel, which consists of a bundle of six alpha-helices with sequence Ac-(LSSLLSL)3-CONH2, exhibits large structural fluctuations. However, in the presence of the field, the bundle adopts a well defined coiled-coil structure with an inner pore of water. The observed structural changes induced by the applied field are consistent with the proposed gating mechanism of the ion channel. 相似文献