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61.
An aqueous extract of a dehydrated garlic preparation with uniform consistency inhibited all eight clinical isolates of the dimorphic fungus,Coccidioides immitis. The inhibitory and lethic concentrations were in the range of 3.12–6.25 mg/ml for both the saprophytic (mold) and parasitic (spherule) forms ofC. immitis. At 6.25-mg/ml concentration, the organism lost its viability within 6 h. The conversion of arthroconidia into spherules in a chemically defined liquid medium was prevented by garlic extract diluted to 1:320 (3.12 mg/ml). The data indicate that components of garlic readily inhibited the in vitro germination and spherulation of this medically important dimorphic fungus. 相似文献
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63.
Xin-Min Cao Lan-Hsiang Huang Chris M. Farnet Melanie Ehrlich 《Biochimica et Biophysica Acta (BBA) - Gene Structure and Expression》1983,741(2):237-243
After digestion by TaqI or nicking by DNAase I, five highly modified bacteriophage DNAs were tested as substrates for T4 DNA ligase. The DNAs used were from phages T4, XP12, PBS1, SP82, and SP15, which contain as a major base either glucosylated 5-hydroxymethylcytosine, 5-methylcytosine, uracil, 5-hydroxymethyluracil, or phosphoglucuronated, glucosylated 5-(4′,5′-dihydroxypentyl)uracil, respectively. The relative ability of cohesive-ended TaqI fragments of these DNAs and of normal, λ DNA to be ligated was as follows: . TaqI-T4 DNA fragments were also inefficiently ligated by Escherichia coli DNA ligase. However, annealing-independent ligation of DNAase I-nicked T4, PBS1, and λ DNAs was equally efficient. We conclude that the poor ligation of TaqI fragments of T4 and PBS1 DNAs was due to the hydroxymethylation (and glucosylation) of cytosine residues at T4's cohesive ends and the substitution of uracil residues for thymine residues adjacent to PBS1's cohesive ends destabilizing the annealing of the restriction fragments. Only SP15 DNA with its negatively charged, modified base was unable to serve as a substrate for T4 DNA ligase in an annealing-independent reaction; therefore, its modification directly interfered with enzyme binding or catalysis. 相似文献
64.
65.
66.
Leukocytic Hypersensitivity in Experimental Group A Streptococcal Infections 总被引:2,自引:0,他引:2 下载免费PDF全文
Skin hypersensitivity to streptococcal antigens was demonstrated in 15 New Zealand red rabbits that were sensitized by intracutaneous injections with group A streptococci, and leukocytic hypersensitivity, as determined by in vitro inhibition of leukocyte migration, was demonstrated in 11 of the rabbits. The skin hypersensitivity persisted for at least 8 weeks, whereas the leukocytic hypersensitivity generally waned rather rapidly. The leukocytic hypersensitivity reappeared in the infected rabbits that had developed this hypersensitivity. However, it did not reappear on reimmunization with living streptococci of the type originally employed, whereas it did reappear with living but not heat-killed streptococci of another M type. 相似文献
67.
Preliminary report on coated charcoal immunoassay of human chorionic "growth hormone-prolactin" and growth hormone 总被引:3,自引:0,他引:3
68.
Antiserum был подготовлен противингибитор вируса haemagglutination (IVH)одна из эмбриона chorioallantoic мембр анныепутем иммун изации морских св инокЭто анти-инги битора в сыворотке заблокирован ингибирование IVH из chorioallantoicмембран в haemagglutination испытанияно ника кого влияния на ре цепторы эритроци товСыворотке кро] ви не влияет рост chorioallantoic мембраны клет ок инет нейтрализ овать воздействи е на вирус гриппа Она снизилась спо собность chorioallantoic мембр ан для adsorb вируса гри ппа, а также степен ь размножения вир усав такого рода тканиАвторы хоте ли бы поблагодари ть г-н Г. Ruttkay-Ne -палубе и для проведения эле ктрофореза меру ния. 相似文献
69.
Data for this study came from breeding records of 27 Père David's (Elaphurus davidianus) hinds maintained in large pastures and from estrous records of four hand-reared nulliparous hinds. The mean estrous cycle length ranged from 17.5 to 19.6 days. Standing estrus resembled that of other cervids, except that a low, moaning vocalization was given in response to contact, and activity (as measured by pedometers) did not increase. Mean gestation length was 183.38 ± SD 6.11 days (n = 21), and nearly all females conceived in the second and third years. The median interbirth interval was 362 days. The median birth date was April 8, and 80% of the births occurred over a 9.5-week period. Multiparous hinds gave birth an average of 20.5 days earlier in the season than primiparous hinds. There was no dimorphism in birth weight. The results are discussed in light of comparative data for other species. 相似文献
70.
Isolation and chromosomal localization of the human En-2 gene 总被引:1,自引:0,他引:1
By low stringency hybridization we have isolated from a human cosmid genomic library sequences homologous with a probe from the Drosophila engrailed gene. Partial nucleotide sequence analysis shows a consensus splice acceptor site followed by an open reading frame (ORF) that can encode 104 amino acids; the first 94 amino acids have 71% identity with the Drosophila engrailed protein. The shared region contains a homeo domain and is within the region of engrailed shared with the Drosophila invected gene and the mouse En-1 and En-2 genes. At the amino acid level, the human sequence is 85% identical with the mouse En-1 gene and 100% identical with the mouse En-2 gene. Hybridization against a panel of human-hamster somatic cell hybrids maps this human En-2 gene to chromosome 7, and regional mapping by in situ hybridization to human chromosomes localizes it to region 7q36 at the end of the long arm. 相似文献