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991.
The sponge Dysidea herbacea (Keller) was found to possess hemagglutinins. The major component, DHA-I, is a protein with a mol. wt of 26,000, which dissociates into subunits of equal size (14,000). It contains large amounts of glutamic acid and aspartic acid residues, but no half-cystine, methionine or histidine residues. DHA-I reacted with rabbit and human AB0 erythrocytes. D-galactose and lactose were effective inhibitors of DHA-I. The sponge also contained a minor component(s) which reacted preferentially with rabbit erythrocytes but not with human AB0 erythrocytes. 相似文献
992.
R A Young V Mehra D Sweetser T Buchanan J Clark-Curtiss R W Davis B R Bloom 《Nature》1985,316(6027):450-452
Leprosy, a chronic infectious disease afflicting between 10 and 15 million people, is caused by the obligate intracellular parasite Mycobacterium leprae. Although M. leprae was the first identified bacterial pathogen of man, basic biochemical, immunological, diagnostic and therapeutic investigations have been severely limited because it remains one of the few human pathogens that have not been cultured in vitro. An M. leprae recombinant DNA expression library was constructed to provide a source of genes encoding proteins relevant for such studies. Monoclonal antibodies directed against M. leprae specific antigens have been used to isolate the genes encoding the five most immunogenic protein antigens of the leprosy bacillus. We report here that M. leprae specific epitopes recognized by all of 13 monoclonal antibodies tested were produced by recombinant phage in Escherichia coli. 相似文献
993.
The effect of tributyltin (TBT) chloride on the growth of cytochrome-deficient and cytochrome-containing cells of Escherichia coli SASX76 was examined. The former cells were found to be at least 20 times more sensitive to TBT. It is proposed that the differential sensitivity of these two cell types to the biocide, TBT, may be due to a different mode of energy generation by cytochrome-deficient and cytochrome-sufficient cells. In addition to the energy state, the pH change caused by the presence and absence of cytochromes which occurred during growth also resulted in a differential sensitivity of these cells. 相似文献
994.
A highly polymorphic DNA marker linked to adult polycystic kidney disease on chromosome 16 总被引:27,自引:0,他引:27
S T Reeders M H Breuning K E Davies R D Nicholls A P Jarman D R Higgs P L Pearson D J Weatherall 《Nature》1985,317(6037):542-544
Adult polycystic kidney disease (APCKD) is a common and often lethal multi-organ disease with an autosomal dominant pattern of inheritance; approximately 1 in 1,000 people carry the mutant gene. The major pathological abnormality is the development and progressive enlargement of cysts in several organs including the liver, pancreas and spleen as well as the kidneys. The basic biochemical defect which leads to the formation of cysts remains unknown. Cyst development, which is not retarded by any known therapy, leads to irreversible renal failure and death at a mean age of 51 unless dialysis or transplantation are used. Patients with the disease account for 9% of chronic dialysis requirement. The first symptoms tend to occur in the fourth decade, after most patients have reproduced. Presymptomatic diagnosis depends on the ultrasonographic detection of cysts, but exclusion cannot be achieved by this means; 34% of at-risk patients in the second decade and 14% in the third will go on to develop cysts after negative diagnosis. The low sensitivity of diagnostic techniques in this critical age-range imposes severe limitations on genetic counselling and the condition cannot be identified prenatally. Hence we have searched for a linkage marker for APCKD; we show here that the APCKD locus is closely linked to the alpha-globin locus on the short arm of chromosome 16 (zeta = 25.85, theta = 0.05). 相似文献
995.
K. Hölzle 《Cellular and molecular life sciences : CMLS》1947,3(4):149-151
Summary It has been found that cyclisation of -halogenated -naphthalene-thioglycolic acids can occur in -position with the elimination of the halogen. The influence of the temperature and of a further substituent (halogen) in the second nucleus are discussed. 相似文献
996.
E. Heilbronner Pl. A. Plattner K. Wieland 《Cellular and molecular life sciences : CMLS》1947,3(2):70-70
Summary Azulene (I) is converted into Naphthalene (II) by heating for 48 hours to 330° C.
74. Mitt. zur Kenntnis der Sesquiterpene. 相似文献
74. Mitt. zur Kenntnis der Sesquiterpene. 相似文献
997.
利用过氧化物过氧化二异丙苯(DCP)和多官能团化合物三烯丙基异氰尿酸酯(TAIC),对聚甲基乙撑碳酸酯(PPC)进行了交联研究。研究发现, DCP和TAIC的用量对PPC的交联均有较大影响, PPC交联后,其凝胶含量、机械性能、弹性模量、玻璃化转变温度均有所增加, 1%的DCP和4%的TAIC用量可得到较理想的交联PPC材料。 相似文献
998.
999.
Methallibure treatment of mature Cyprinus carpio causes a marked reduction in the steroidogenesis, as indicated by the fall in 3beta-HSD activity in the gonads. Significance of these results is discussed. 相似文献
1000.