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101.
L. Bern O. Lidefelt J. N. Schöön H. 《Journal of the American Oil Chemists' Society》1976,53(7):463-466
The mass transfer of hydrogen in fat hydrogenation was studied in two geometrically similar reactors of 30 and 500 liter capacity
equipped for hydrogen recirculation. A scale-up rule was formulated on the basis of the experiments and checked in industrial
hydrogenations with a 24 m3 reactor. The scale-up rule found was similar to the equal mixing time rule. 相似文献
102.
G Lennartson A Lundblad S Sj?blad S Svensson PA Ockerman 《Canadian Metallurgical Quarterly》1976,3(2):51-54
A gas chromatographic mass spectrometric method has been developed for the rapid determination of a urinary tetrasaccharide (alpha-D-Glc-(1 leads to 6)-alpha-D-Glc-(1 leads to 4)-alpha-D-Glc-(1 leads to 4)-D-Glc). The urine sample is first fractionated by gel chromatography. An appropriate internal standard is added to the pooled tri-pentasaccharide fraction, which is then reduced, methylated and fractionated by g.c. The identification of the tetrasaccharide derivative is based on the g.c. relative retention time and the mass spectrum of the reduced permethylated tetrasaccharide. The normal excretion rate was in the range of 0.1-2.5 mg per 24 hours. Greatly increased amounts (9.4-89.6 mg 24 h-1) were found in the urine of patients with glycogen storage disease type II and type III and in one patient with unclassified muscular disease. A moderate increase (3.6m6 mg 24 h-1) was observed in one patient with glycogen storage disease type VI, in two patients with Duchenne muscular dystrophy and in two other patients with unclassified muscular disease. 相似文献
103.
We examined the therapeutic effect of cefluprenam (CFLP) on the polymicrobial urinary tract infection associated with infectious stones as compared to that of ceftazidime (CAZ), using the experimental polymicrobial urinary tract infection caused by Proteus mirabilis (P. mirabilis), Pseudomonas aeruginosa (P. aeruginosa) and Enterococcus faecalis (E. faecalis). In order to form bladder stones in rats, a sterile zinc ring was implanted as a foreign body, followed by inoculating P. mirabilis E05106 transurethrelly. Thereafter, P. aeruginosa E030033 and E. faecalis 966 were inoculated according to the same way. CFLP or CAZ was administered intravenously twice a day for 5 days. The therapeutic effect was evaluated by the eradication of these bacteria from the urine, the kidney and stones, inhibition of growth of stones, and also a value of BUN. The urinary excretion rates of CFLP and CAZ was also determined (20 mg/kg). In result, CFLP significantly more effective in the eradication of P. mirabilitis, P. aeruginosa and E. faecalis from the urine, the kidney and stones than the control than the control (p < 0.05). Furthermore, CFLP significantly more effective in the eradication of P. aeruginosa from the urine and also E. facalis from the urine and stones (p < 0.05). Meanwhile, CAZ significantly more effective in the eradication of P. mirabilis from the urine, the kidney and stones and also P. aeraginosa from the kidney and stones than the control. However, CAZ did not show eradicative effect on E. faecalis. The urinary excretion rates of CFLP and CAZ at rats were 59.3% and 59.4%, respectively, within 8 hrs after administration, showing a similar excretion pattern. CFLP exhibited the prominent therapeutic effect on polymicrobial urinary tract infection associated with infectious stones caused by P. mirabilis, P. aeruginosa and E. faecalls. On the basis of these results, it has been strongly suggested that CFLP is highly beneficial in the management of intractable polymicrobial urinary tract infectious in clinic. 相似文献
104.
The gastrointestinal pathogen Helicobacter pylori requires supplementation with either fetal calf serum (FCS), bovine serum albumin (BSA), or (2,6-dimethyl)-beta-cyclodextrin (CD) for growth in a complex or defined medium. Because the availability of medium in which all components were chemically defined would facilitate metabolic studies of H. pylori, growth of the type strain, ATCC 43504, was compared in a defined medium with different growth additives. The dependency of H. pylori growth on FCS or BSA in a defined medium could partially be replaced by dependency on CD and cholesterol when the last two components were both added to the defined medium. Growth and cell yield were not affected by the addition of glucose, but the culture viability (numbers of CFU per milliliter was extended. Because therapeutic antifoams are used to relieve gastrointestinal symptoms we studied whether the unique susceptibility of H. pylori to the emulsifier polyoxyethylene-20-stearylether (Brij 78) was growth dependent or medium specific. The bactericidal activity exerted in buffer at pH 5 was independent of the preculture medium, and a 5-h exposure of the bacteria to 1.28 to 2.56 microg of Brij 78 per ml reduced the numbers of viable bacteria by >5 log10. The MICs (0.16 to 0.32 microg/ml) were lower than the corresponding minimal bactericidal concentrations in different growth media and were affected by FCS or BSA. In conclusion, CD plus cholesterol promotes the growth of H. pylori in a serum-free defined medium in which glucose enhances cell viability. The antibacterial activity exerted by Brij 78 is neither growth dependent nor medium specific. 相似文献
105.
Nine women were given bromocriptine a few days after delivery in order to inhibit lactation. Nasal airway resistance to airflow (NAR) was recorded and blood samples were taken before treatment with bromocriptine, 2 to 3 hours after the first dose of this drug, and after 3 to 5 days on this treatment. All the women had increased nasal congestion after bromocriptine and NAR rose significantly. The prolactin, estradiol, and progesterone hormone levels decreased significantly, but no significant difference was found in the levels of thyroid-stimulating hormone (TSH) and vasoactive intestinal polypeptide (VIP). The bromocriptine effect may be caused by different mechanisms. 相似文献
106.
A Junker G Baatrup SE Svehag P Wang E Holmstr?m G Sturfelt AG Sj?holm 《Canadian Metallurgical Quarterly》1998,47(5):481-486
OBJECTIVE: Our objectives were to assess the clinical and microbiological aspects of septic osteoarthritis in children admitted to our center from 1987 until July 1997 and to determine the sensitivity of ultrasound in this age group. PATIENTS AND METHODS: The medical records of 36 children diagnosed as having septic osteoarthritis of the hip were reviewed retrospectively. The diagnosis had been based on clinical criteria, along with synovectomy and drainage of purulent material from the affected joint. An X-ray and/or ultrasound had been performed when the diagnosis was suspected. RESULTS: Nineteen children were diagnosed during the neonatal period, 8 between the ages of 1 and 12 months and 9 older than one year of age. Mean age at diagnosis was 16.8 +/- 6.2 months (median 29 days, range 6 days to 13 years). The hip was involved in 32 children, the ankle in 3 and the elbow in 1. A microbiological diagnosis was achieved in 22 cases (61%) by culture from blood, CSF, and/or synovial fluid. The most common isolates were Gram positive cocci (S. aureus in 9 cases and coagulase negative Staphylococcus in 3). The diagnostic value of the X-rays was very low (18%). The ultrasound was initially considered abnormal in 64.5% of the patients, with a lower sensitivity in the neonatal period. After a mean follow-up period of 36 months, the outcome was good in 86% of the cases, although three children continue with sequelae. Two preterm infants died due to sepsis associated with the osteoarthritis. CONCLUSIONS: At the time of diagnosis of septic arthritis of the hip, the ultrasound is frequently normal. Due to the poor outcome when there is a delay in surgery, we suggest immediate synovectomy and drainage when there is clinical suspicion of septic arthritis despite an apparently normal ultrasound. 相似文献
107.
Potato is one of the world's most widely grown tuber crop, in which starch is the predominant form of carbohydrates. Potatoes can be prepared in many ways: boiled, fried or roasted. Frying and roasting potatoes at high temperatures result in an appetizing crust, but at the same time acrylamide can form. In this study, the concentrations of the acrylamide precursors, asparagine and sugars, were determined in five different Swedish-grown potato varieties, together with the acrylamide content after typical home-cooking procedures; oven-roasting of potato wedges and pan-frying of cubes of boiled potatoes. Pan-frying of boiled potato cubes resulted in higher levels of acrylamide (530-1100 microg/kg) than in the wedges (140-250 microg/kg). Blanching combined with a shorter roasting time was shown to be an efficient way of reducing the acrylamide content in roasted potato wedges, especially in the experiments performed after long-term storage, where the acrylamide content was reduced from 110-260 to 50-140 microg/kg. No correlation was found between precursor content and acrylamide content, and this finding emphasizes the need for further studies on factors affecting acrylamide formation, for example, the availability of precursors at the surface during cooking. 相似文献
108.
Saloranta TM Armitage JM Haario H Naes K Cousins IT Barton DN 《Environmental science & technology》2008,42(1):200-206
Multimedia environmental fate models are useful tools to investigate the long-term impacts of remediation measures designed to alleviate potential ecological and human health concerns in contaminated areas. Estimating and communicating the uncertainties associated with the model simulations is a critical task for demonstrating the transparency and reliability of the results. The Extended Fourier Amplitude Sensitivity Test(Extended FAST) method for sensitivity analysis and Bayesian Markov chain Monte Carlo (MCMC) method for uncertainty analysis and model calibration have several advantages over methods typically applied for multimedia environmental fate models. Most importantly, the simulation results and their uncertainties can be anchored to the available observations and their uncertainties. We apply these techniques for simulating the historical fate of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the Grenland fjords, Norway, and for predicting the effects of different contaminated sediment remediation (capping) scenarios on the future levels of PCDD/Fs in cod and crab therein. The remediation scenario simulations show that a significant remediation effect can first be seen when significant portions of the contaminated sediment areas are cleaned up, and that increase in capping area leads to both earlier achievement of good fjord status and narrower uncertainty in the predicted timing for this. 相似文献
109.
Saif Ullah Pierrick Anthony Mindykowski Rolff Ripke Leisted Sergey Chernyy Sie Woldum Tordrup Grunde Jomaas Kristoffer Almdal 《火与材料》2020,44(7):966-974
A novel intumescent (carbonization, acid donor and foaming) fire retardant that mimics carbon nanotubes was introduced into bitumen roofing and characterized using cone calorimetry as the main analytical tool. The experimental results indicate that 18% (by mass) attapulgite mineral (ATTP) mixed with base bitumen decreased the peak heat release rate per unit area (pHRRPUA) by 10%. Further, incorporation of melamine coated ammonium polyphosphate (MAPP) decreased the pHRRPUA by 52% and a mixture of these (3:1, ATTP:MAPP) decreased the pHRRPUA by 25% as compared to adding CaCO3 as a filler. The residual mass loss after the cone test was also improved with up to 3%. The indication of a positive synergistic flame retardant effect of the ATTP-MAPP mixture is supported by thermogravimetric analysis. The addition of this rod-like mineral improved the general fire retardant properties of the base bitumen and increased the viscosity. Therefore, the polymer-modified bitumen with both fire retardant and rheological properties (providing mechanical strength) is a promising novel approach in the design of bitumen roofing membranes. 相似文献
110.
Constantin Mihai Gabriel Ştefan Liviu-Daniel Ionescu Bogdan Duong Ngoc Q. K. Demarty Claire-Héléne Sjöberg Mats 《International Journal of Computer Vision》2021,129(5):1526-1550
International Journal of Computer Vision - In this paper, we report on the creation of a publicly available, common evaluation framework for image and video visual interestingness prediction. We... 相似文献