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1.
GC Viscomi 《Canadian Metallurgical Quarterly》1997,10(1):59-86
Type I IFNs constitute a family of proteins exhibiting high homology in primary, secondary, and tertiary structures. They interact with the same receptor and transmit signals to cellular nucleus through a similar mechanism, eliciting roughly homogeneous biological activity. Nevertheless, the members of that family, IFN alpha species, IFN beta and IFN omega, due to local differences in the structure sometime show distinct properties. From the reported data it results that even minute changes or differences in the primary sequences could be responsible for a significant variety of biological actions, thus inducing to the hypothesis that Type I IFNs, rather than to be the result of a redundant replication during the evolution play definite roles in the defense of living organisms to foreign agents. 相似文献
2.
K. L. Mikolajczak M. O. Bagby I. A. Wolff 《Journal of the American Oil Chemists' Society》1965,42(3):243-245
Methyl crepenynate (methyl-cis-9-octadecen-12-ynoate) is readily isomerized by potassium hydroxide in ethylene glycol to an 8,10,12-octadecatrienoic acid
in good yield. A reaction carried out at 120C for 1 hr in 10% base is sufficient to convert the nonconjugated enyne system
completely to conjugated triene systems.
Presented at AOCS Meeting in New Orleans, 1964.
A laboratory of the No. Utiliz. Res. & Der. Div., ARS, USDA. 相似文献
3.
A common difficulty encountered in method of moments (MoM) solutions in electromagnetics is that of cavity resonance. The author presents a simple, automated technique to diagnose and correct spurious numerical results caused by such cavity resonances. An illustration of the application of this technique to a well known electromagnetic (EM) scattering problem is presented and discussed 相似文献
4.
K. D. Carlson A. Chaudhry R. E. Peterson M. O. Bagby 《Journal of the American Oil Chemists' Society》1990,67(8):495-498
To conduct product development research onLesquerella seed oils, we explored methods to obtain >100 g quantities of lesquerolic (14-hydroxy-cis-11-eicosenoic) acid. Preliminary experiments with open-column silica gel chromatography showed thatL. fendleri oil could be separated into 3 triglyceride (TG) fractions. The first (10%) contained nonhydroxy 16-(13%) and 18-carbon acids
(65% 18∶1,2,3). The second fraction (15%) contained monolesquerolins (39% lesquerolic acid). The major TG fraction (73%) was
mainly dilesquerolins (66% lesquerolic acid) showing that a hydroxy acid-enriched TG oil was obtainable by this procedure.
Silica gel chromatography easily separatedL. fendleri fatty acid methyl esters (FAME) into a hydroxy-free ester fraction (40–44%) consisting largely of 18∶1 (39%), 18∶2 (19%)
and 18∶3 (31%), and a hydroxy ester fraction (56–60%) that was largely methyl lesquerolate (94%) with small amounts of auricolate
(5%) (14-hydroxy-cis-11,cis-17-eicosadienoate) and traces of 18-carbon hydroxy esters. This process for isolating the hydroxy FAME ofLesquerella oil was scaled up 15-to 100-fold with a preparative high performance liquid chromatograph. Thirty-gram samples ofL. gordonii FAME were dissolved in eluting solvent, pumped onto the high performance liquid chromatography (HPLC) silica column and eluted
with 97∶3 hexane/ethyl acetate. In an 8-hr period, up to 200 g of methyl lesquerolate could be obtained with a purity >98%,
the only contaminants being methyl auricolate and methyl ricinoleate.
Presented at the AOCS meeting in Phoenix, AZ, May 1988.
The mention of firm names or trade products does not imply that they are endorsed or recommended by the U.S. Department of
Agriculture over other firms or similar products not mentioned. 相似文献
5.
Chicken semen undiluted, diluted with a diluent containing fructose and/or mixed with turkey semen was used to inseminate Leghorn hens. In two of three experiments there was an improvement in fertility from insemination by mixed semen as compared to semen diluted to the same extent with the diluent. 相似文献
6.
War is a complex social situation due to the interplay of multiple factors. Economical and political ones are of utmost importance, but human attitudes and motivations must be also taken into account. Being desirable to modify human transactions in such a way that they do not interfere with the basic right of everyone to a condition of physical and mental well-being, war must be abolished. The author contends that an understanding of behaviour through Psychology can be helpful in that aim. Aggression is considered the principal psychological cause of war. It is worth while to differentiate between aggression as an instrument for attaining a special end, and as pure hostility. Only in the first form, it is held here, does it play an important role in war. Psychogists must deal also with a wide range of states of mind that can be "served" by aggression: feelings of inferiority or insecurity, fear, greed, projections, compensations, rationalizations, etc. Scientific approach is not the only one Physiology brings to war prevention. It is equally important the wide dissemination of its conclusions among the general public. Information on the dynamics that prompt people to decide war would make it easier to control. This applies not only to political or military leaders, but also to civil populations. Concerning those two possible contributions of psychologists, scientific and educative, it is suggested the extensive use of psychodramatic techniques. Their richness lie in the lifelike experiences they convey to the participants, and particular aptitude to promote changes of attitudes. Investigation and information on the psychological processes related to war should be undertaken by international organizations of social scientists, acting simultaneously in several countries. Some of the initial steps they could further: 1) that prevention of war be a current subject matter in psychological courses; 2) that the World Health Organization take interest in this subject; 3) that psychologists participate in international political and economical bodies in order to clarify the psychological factors leading to war. 相似文献
7.
Polymerization of vegetable oils and their uses in printing inks 总被引:4,自引:0,他引:4
Ink vehicles were prepared by the polymerization of vegetable oils. By controlling the polymerization conditions, the desired
viscosity, color and molecular weight could be achieved for a variety of vegetable oils with a broad range of iodine values
and fatty acid compositions. The effect of temperature and catalyst on polymerization rates were evaluated, and polymerization
rate constants were calculated. Of the oils tested, the polymerization rate constant of safflower oil was the highest, followed
by soybean, sunflower, cottonseed and canola oils in decreasing order. Use of a catalyst shortened the heating time by about
25–50% or lowered the polymerization temperature requirement by 25–30°C. 相似文献
8.
J. -K. Huang P. F. Dowd K. C. Keudell W. E. Klopfenstein L. Wen M. O. Bagby A. C. Lanser R. A. Norton 《Journal of the American Oil Chemists' Society》1996,73(11):1465-1469
Transformation of 12-hydroxyoctadecanoic acid (12-HOA) to 5-n-hexyl-tetrahydrofuran-2-acetic acid (5-HTFA) byBacillus lentus NRRL B-14864 (B-14864) was carried out in the presence or absence of oligomycin, 2-bromooctanoic acid (2-BA), or sodium azide.
In addition, several saturated and monounsaturated monohydroxyfatty acids, saturated monooxofatty acids, and monounsaturated
fatty acid were used as substrates for transformation reactions by B-14864 or corynebacterium FUI-2. Methyl esters of the
transformation products were analyzed by gas chromatography and gas chromatography/mass spectroscopy. Various γ-lactones and
tetrahydrofuran fatty acid derivatives were conversion products when saturated monohydroxyfatty acids were used as substrates;
the production of 5-HTFA from 12-HOA by B-14864 cells was completely inhibited in the presence of high concentration of oligomycin,
2-BA, or sodium azide; and fatty acid β-oxidation metabolic intermediates, 6-hydroxydodecanoic, 4-oxododecanoic, and 4-oxodecanoic
acids were products when 12-HOA, 10-oxo-, and 12-oxooctadecanoic acids were used as substrates. Our results suggest that the
production of 5-HTFA from 12-HOA by B-14864 was through the fatty acid β-oxidation pathway. Three-day-old driedfruit beetle
pupae were topically treated with 5-HTFA to test for juvenile hormone activity, and 5-HTFA was found to possess juvenile hormone-like
activity in pure form but not when it was diluted to 10%.
Presented in part at the 37th West Central States Biochemistry Conference Annual Meeting, Columbia, Missouri, Oct. 1994. 相似文献
9.
Peripheral limb ischaemia is rare in children. We have treated only 12 infants and children with this condition in the past 15 years at the Royal Hospital for Sick Children in Glasgow. There were nine neonates and three older children. Most were suffering from life-threatening illnesses or severe infection. Two were born with ischaemic arms with no apparent cause. We have analysed the factors leading to ischaemia, the outcome of the initial treatment and the later orthopaedic problems. Two required amputation of both legs, one of an arm, two of feet and one of toes. Two had skin grafts. All surgery was performed after demarcation was well established and delayed closure was used after amputation. Five children developed limb-length discrepancy or an angular deformity. To date two have required additional corrective surgery. 相似文献
10.