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排序方式: 共有423条查询结果,搜索用时 15 毫秒
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J. R. Daly M. R. Fletcher D. Glass D. J. Chambers Lucille Bitensky J. Chayen 《BMJ (Clinical research ed.)》1974,2(5918):521-524
The development of the highly sensitive cytochemical bioassay for ACTH has permitted the measurement of plasma ACTH levels during the insulin hypoglycaemia test (I.H.T.) in patients treated with corticosteroids and corticotrophin. The ACTH, corticosteroid, and growth hormone (GH) responses in the I.H.T. were measured in three groups of 12 rheumatoid arthritis patients. One group was receiving long-term corticotrophin treatment, the second was undergoing long-term corticosteroid treatment, and the third had never received systemic hormone therapy. The increments in plasma ACTH, corticosteroids, and GH were diminished in the corticosteroid-treated group, as were increments in plasma GH and ACTH in the corticotrophin-treated group; but in this group the corticosteroid increment was normal. Examination of the area under the curve of the ACTH response showed that the total amount of ACTH secreted was normal though the rate of secretion was reduced. In the corticosteroid-treated group both rate and total secretion were diminished. 相似文献
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Microbiological Degradation of Malodorous Substances of Swine Waste under Aerobic Conditions 总被引:2,自引:1,他引:1 下载免费PDF全文
Denis Bourque Jean-Guy Bisaillon Rjean Beaudet M. Sylvestre Muhammad Ishaque Andr Morin 《Applied microbiology》1987,53(1):137-141
Phenol, p-cresol, and volatile fatty acids (VFA; acetic, propionic, isobutyric, butyric, isovaleric, and valeric acids) were used as odor indicators of swine waste. Aeration of the waste allowed the indigenous microorganisms to grow and degrade these malodorous substances. The time required for degradation of these substances varied according to the waste used, and it was not necessarily related to their concentrations. Using a minimal medium which contained one of the malodorous compounds as sole carbon source, we have selected from swine waste microorganisms that can grow in the medium. The majority of these microorganisms were able to degrade the same substrate when inoculated in sterilized swine waste but with an efficiency varying from one strain to the other. None of these strains was able to degrade all malodorous substances studied. Within 6 days of incubation these selected strains degraded the following: Acinetobacter calcoaceticus, phenol and all VFA; Alcaligenes faecalis, p-cresol and all VFA; Corynebacterium glutamicum and Micrococcus sp., phenol, p-cresol, and acetic and propionic acids; Arthrobacter flavescens, all VFA. On a laboratory scale, the massive inoculation of swine waste with C. glutamicum or Micrococcus sp. accelerated degradation of the malodorous substances. However, this effect was not observed with all of the various swine wastes tested. These results suggest that an efficient deodorization process of various swine wastes could be developed at the farm level based on the aerobic indigenous microflora of each waste. 相似文献
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Assignment of autosomal dominant spinocerebellar ataxia (SCA1) centromeric to the HLA region on the short arm of chromosome 6, using multilocus linkage analysis. 总被引:6,自引:6,他引:0 下载免费PDF全文
H Y Zoghbi L A Sandkuyl J Ott S P Daiger M Pollack W E O''''Brien A L Beaudet 《American journal of human genetics》1989,44(2):255-263
A 7-generation kindred with the HLA-linked form of spinocerebellar ataxia (SCA1) was studied to determine whether the SCA1 gene maps centromeric or telomeric to the HLA loci. The DNA markers flanking the HLA-(A-B) region were used for polymorphism studies and multilocus linkage analysis. These two markers are the cDNA for the beta-subunit of HLA-DP, which is centromeric to HLA-(A-B), and the cDNA for coagulation factor XIIIa (F13A), which is telomeric to HLA-(A-B). Haplotypes were constructed using multiple polymorphisms for these two DNA markers, and pairwise linkage analysis revealed a maximum lod score of 2.18 for SCA1 versus HLA-DP at a recombination fraction of .05 and a maximum lod score of 0 for SCA1 versus F13A at a recombination fraction of .50. A possible crossover between HLA-(A-B) and HLA-DP was identified, but lack of samples from key individuals hampered the analysis. To clarify the phase and improve the analysis, the two chromosomes 6 for the crossover individual were separated in somatic cell hybrids. The results strongly favored the probability that the crossover occurred between HLA-(A-B-DR) and HLA-DP with SCA1 segregating with HLA-DP, consistent with a location centromeric to HLA-(A-B). Multilocus linkage analysis was used to evaluate further the location of SCA1 relative to F13A, HLA-(A-B), and HLA-DP; the results indicated that the SCA1 gene locus is centromeric to HLA-DP with odds of 46:1 favoring this most likely location over the second most likely location, i.e., telomeric to HLA-(A-B) between the HLA complex and F13A. 相似文献
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Deletion and linkage mapping of eight markers from the proximal short arm of chromosome 6 总被引:3,自引:0,他引:3
H Y Zoghbi C M Ballantyne W E O'Brien A E McCall T J Kwiatkowski S A Ledbetter A L Beaudet 《Genomics》1990,6(2):352-357
Eight chromosome 6p markers (MUT, D6S4, D6S5, D6S19, D6S29, PIM, HLA, and F13A) were regionally mapped using somatic cell hybrid deletion cell lines that retained different regions of chromosome 6p. New restriction fragment length polymorphisms were identified at the D6S5 and PIM loci using newly isolated genomic clones at these loci. Genetic linkage among the eight loci was determined using the 40 CEPH reference families. Linkage analyses showed that these loci are in one linkage group spanning 48 cM in males and 128 cM in females. Using both the deletion mapping data and multipoint linkage analyses, chromosomal order for these loci was determined as centromere-(MUT, D6S4)-(D6S5, D6S19)-(D6S29, PIM)-HLA-F13-A-telomere. Analyses of sex-specific recombination frequencies revealed a higher rate of recombination in females in the region between D6S4 and D6S29, while the recombination rate in males was higher for the interval between D6S29 and the HLA loci. 相似文献
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Isolation and Genetic Analysis of Caulobacter Mutants Defective in Cell Shape and Membrane Lipid Synthesis 总被引:1,自引:0,他引:1
In this paper we report the isolation, characterization and genetic analysis of several C. crescentus mutants altered in membrane lipid synthesis. One of these, a fatty acid bradytroph, AE6002, was shown to be due to a mutation in the fatA gene. In addition to the presence of the fatA506 mutation, this strain was found to contain two other mutations, one of which caused the production of a water-soluble brown-orange pigment (pigA) and another which caused formation of helical cells (hclA). Expression of the latter two phenotypes required complex media and both were repressed by glucose. However, the lesions were mapped to loci that are separated by a substantial distance. The hclA and the fatA genes mapped close together, possibly implying that comutation had occurred in AE6002. Data are presented that allow the unambiguous identification of a second Fat gene (fatB) in C. crescentus. The map position of another mutation in membrane lipid biogenesis, the glycerol-3-PO4 auxotroph gpsA505, was also determined. During this study the flaZ gene was fine-mapped and the positions of proC and rif changed from the previously reported location. 相似文献