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991.
992.
A 2 X 2 factorial experiment (protein 12.5 and 15.5; methionine hydroxy analog 0 and .125% dry matter) included 144 cows for one complete lactation, distributed over seven locations. Rations were formulated to the desired protein, methionine analog, and constant amounts of fiber 17%, sulfur .225%, calcium .6%, phosphorus .4%, and salt .5%. Treatment effects were not apparent for dry matter intake, daily milk and fat-corrected milk production, conversion of energy, and body weight changes. Conversion of dietary crude protein into milk protein was 34.5% for the low and 25.8% for the high protein ration. Methionine analon (0% = 2.54; .125% = 1.90). Effect of methionine analog was most apparent at low protein as 0 analog cows produced 247 kg fat, required 2.9 services/contraception, and had 156 days open whereas cows on other treatments (.125% analog and/or high protein) produced 264 kg fat, required 1.8 to 2.2 services/conception, and had 124 to 134 days open. Methionine analog response is discussed in relation to tuminal and postruminal effects as well as the interrelation with protein and energy.  相似文献   
993.
994.
Proceedings: The effect of carbon monoxide on humans   总被引:1,自引:0,他引:1  
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995.
Heparan sulfate (HS) polysaccharides interact with numerous proteins at the cell surface and orchestrate many different biological functions. Though many functions of HS are well established, only a few specific structures can be attributed to HS functions. The extreme diversity of HS makes chemical synthesis of specific bioactive HS structures a cumbersome and tedious undertaking that requires laborious and careful functional group manipulations. Now that many of the enzymes involved in HS biosynthesis are characterized, we show in this study how one can rapidly and easily assemble bioactive HS structures with a set of cloned enzymes. We have demonstrated the feasibility of this new approach to rapidly assemble antithrombin III-binding classical and non-classical anticoagulant polysaccharide structures for the first time.  相似文献   
996.
997.
Between 1968 and 1977 there were 4 113 109 primary smallpox vaccinations in France. There were 30 deaths but no deaths occurred after re-vaccination. The mortality can be analysed as follows: -- proven or probable cases: 1.5 death/million vaccinations; -- proven, probable or possible cases 2.9/million vaccinations; -- proven, probable, possible or doubtful 7.3 cases/million vaccinations. The risk of death is 3 to 4 times greater under the age of one year and an overall death rate of 6/million vaccinations in reasonably accurate.  相似文献   
998.
A newborn infant was seen with severe and progressive arterial hypertension, congenital atresia of the abdominal aorta, and a renal venous renin activity ratio greater that 1:1.5 (1:3.1). Preoperative studies indicated that the renin-angiotensin axis was responsible for the production and maintenance of the severe hypertensive process. Right nephrectomy cured the arterial hypertension both above and below the area of coarctation. The possible roles of the pathogenic mechanism are discussed.  相似文献   
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