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61.
R. Rodney Howell Amir I. Arbisser David S. Parsons Charles I. Scott Ursula Fraustadt William R. Collie Robert N. Marshall Oscar Cavazos Ibarra 《American journal of human genetics》1981,33(6):957-967
We have defined a new autosomal recessive disorder in patients stemming from a small community in northern Mexico. Diagnosable at birth, its major symptoms include brittle hair, mental retardation, and nail dysplasia. Structural hair abnormalities are seen by both light and electron microscopy. Hair cystine content is reduced while the copper/zinc ratio in hair is increased. 相似文献
62.
Thirty-six attempts were made to isolate from the uterine flushings of culture positive and serologic reactor cows. Sixteen of these attempts were made after cows had been programmed for superovulation and a simultaneous attempt was made to recover eggs. Udder secretion samples for culture and blood for serology were collected at the time of the flushing procedure. In addition, a field isolate of suspended in three different solutions (one commonly used for nonsurgical embryo retrieval) was quantitated at various intervals up to 24 hours.Brucellae were not cultured from any of the uterine flushings although it was demonstrated that the organisms would remain viable in the media used for up to 24 hours. Udder secretions contained brucella at the time of flushing in 17 of the 36 attempts. Results indicated that transfer from infected donors might be achieved without transfer of infection. It is cautioned that final evidence of success would have to come after recipients had undergone serologic and cultural surveillance through their gestation period. 相似文献
63.
Electrophoretic mobility studies of colloidal particles in pig effluent show that hydrolysable cations reverse the charge of these particles only in freshly aerated effluent. Effluent which had been left standing for longer than fifteen to twenty days after aeration shows no charge reversal. Optimal flocculation cannot be achieved for this effluent. 相似文献
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Hydrolysis of cellulose by Trichoderma viride cellulase reached a plateau after some 25 hr. If the initial enzyme-to-substrate ratio was low, resuspension of substrate in fresh enzyme or addition of enzyme resulted in further high rate hydrolysis. This did not occur if the initial ratio was high. Over 75% hydrolysis might be achieved in the former case, while less than 60% in the latter. A model postulating inactivation of adsorbed enzyme–substrate complex which blocked further hydrolysis was proposed, and it was found to fit the data well. The proposed model had five parameters, four of which could be checked by graphical methods, and all of which had physical meanings. The parameters were estimated by a nonlinear least-squares minimization FORTRAN computer program, using numerical integration and optimization of the parameters. The model was used to predict the resuspension data, powdered enzyme addition data, cellobiose addition data, and cellulose addition data; the deviations from the model are discussed. It was found that average values could be used for four out of the five parameters, while the fifth (initial enzyme concentration) did not correlate with independent measurements such as the filter paper activity or protein concentration. 相似文献
66.
Robert D. Stipanovic Alois A. Bell Marshall E. Mace Charles R. Howell 《Phytochemistry》1975,14(4):1077-1081
The triterpenoid aldehydes, gossypol (1), 6-methoxygossypol (2) and 6,6′-dimethoxygossypol (3); and the sesquiterpenoid aldehydes, hemigossypol (4) and methoxyhemigossypol (5), were isolated from 1-week-old roots of Gossypium hirsutum and G. barbadense and identified. This is the first report of 2 and 3 in nature and of 4 and 5 from healthy roots. Compounds 2 and 3 also constituted 30% of the total terpenoid aldehydes in the seeds of 1 cultivar of G. barbadense, but occurred only in trace quantities in those of G. hirsutum. Spectral data (UV, IR, NMR, MS) and proof of structure for 2 and 3 are presented. 相似文献
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