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1.
The assembly of a large physical map of genomes requires simultaneous analysis of many cosmid clones for overlapping regions. The search for overlapping regions may be achieved by various means. High-performance liquid chromatography (HPLC) provides an alternative to gel electrophoresis since microgram amounts of each DNA fragment may be collected into individual test tubes for further analysis. HPLC has been used to identify overlapping cosmid clones from a pool of cosmid DNA containing the terminal portion of the long arm of the human X chromosome (Xq24-qter). Among 400 cosmids analyzed, 3 were shown to overlap. 相似文献
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Class II genes of the human major histocompatibility complex. The DO beta gene is a divergent member of the class II beta gene family 总被引:14,自引:0,他引:14
A novel class II beta chain gene is described. This gene, tentatively called DO beta, displays considerably less polymorphism than beta genes of the DP, DQ, and DR loci. The nucleotide sequence of the DO beta gene is strikingly similar to that of the previously identified murine A beta 2 gene. The DO beta gene displays the same exon/intron organization as other beta genes although the fifth exon and the translated portion of the sixth exon are longer than in other genes. A striking feature of the amino acid sequence deduced from the DO beta gene sequence is the pronounced hydrophobicity of the NH2-terminal region. This feature distinguishes the putative DO beta chain from other class II beta chains and raises the possibility that DO beta chains may interact with an alpha chain that is structurally different from those of the DP, DQ, and DR loci. It further suggests that the putative DO molecule may have a function different from those of other class II antigens. 相似文献
4.
Michelle de C. S. Azevedo Patricia S. Rosa Cleverson T. Soares Luciana R. V. Fachin Ida Maria F. D. Baptista William J. Woods Gustavo P. Garlet Ana Paula F. Trombone Andrea de F. F. Belone 《PloS one》2015,10(12)
Jorge Lobo’s disease (JLD) is a chronic infection that affects the skin and subcutaneous tissues. Its etiologic agent is the fungus Lacazia loboi. Lesions are classified as localized, multifocal, or disseminated, depending on their location. Early diagnosis and the surgical removal of lesions are the best therapeutic options currently available for JLD. The few studies that evaluate the immunological response of JLD patients show a predominance of Th2 response, as well as a high frequency of TGF-β and IL-10 positive cells in the lesions; however, the overall immunological status of the lesions in terms of their T cell phenotype has yet to be determined. Therefore, the objective of this study was to evaluate the pattern of Th1, Th2, Th17 and regulatory T cell (Treg) markers mRNA in JLD patients by means of real-time PCR. Biopsies of JLD lesions (N = 102) were classified according to their clinical and histopathological features and then analyzed using real-time PCR in order to determine the expression levels of TGF-β1, FoxP3, CTLA4, IKZF2, IL-10, T-bet, IFN-γ, GATA3, IL-4, IL-5, IL-13, IL-33, RORC, IL-17A, IL-17F, and IL-22 and to compare these levels to those of healthy control skin (N = 12). The results showed an increased expression of FoxP3, CTLA4, TGF-β1, IL-10, T-bet, IL-17F, and IL-17A in lesions, while GATA3 and IL-4 levels were found to be lower in diseased skin than in the control group. When the clinical forms were compared, TGF-β1 was found to be highly expressed in patients with a single localized lesion while IL-5 and IL-17A levels were higher in patients with multiple/disseminated lesions. These results demonstrate the occurrence of mixed T helper responses and suggest the dominance of regulatory T cell activity, which could inhibit Th-dependent protective responses to intracellular fungi such as L. loboi. Therefore, Tregs may play a key role in JLD pathogenesis. 相似文献
5.
P. J. Vuorinen S. Peuranen M. Keinänen C. Tigerstedt J. Raitaniemi M. Rask 《Zeitschrift fur angewandte Ichthyologie》2004,20(3):217-224
The acute effects on perch and long‐term effects on whitefish were studied after liming one side of a lake [initial pH: 4.6–5.5; aluminium (Al): 29–54 μg L?1; Ca2+: 0.02–0.07 mmol L?1] that was divided into two parts with a plastic curtain. Some Al precipitation was observed on the gill surface of perch 1 day after liming; the concentration of plasma sodium of perch females in the limed side was also higher than in the acidic side. Nearly 6 months after liming, at the spawning time of whitefish, the plasma chloride concentration of whitefish in the limed side was higher and blood glucose concentration lower than in the acidic side. Four of five whitefish males from the limed side, but only one of five males and none of the five females from the acidic side, were ready to spawn. The growth of whitefish in the limed side was also more rapid. These changes illustrate that liming had no acute harmful effects on perch, and allowed whitefish to recover from acidity‐related physiological stress. 相似文献
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Structure of a gene encoding the 1.7 S storage protein, napin, from Brassica napus 总被引:14,自引:0,他引:14
L G Josefsson M Lenman M L Ericson L Rask 《The Journal of biological chemistry》1987,262(25):12196-12201
8.
Heike Schmidt Rüdiger Bode Ida A. Samsonova Dieter Birnbaum 《Applied microbiology and biotechnology》1989,31(5-6):463-466
Summary Mutants of Candida maltosa were isolated that lacked saccharopine reductase (lys9) and saccharopine dehydrogenase (lys1) and were able to accumulate -aminoadipate--semialdehyde (AASA) in the cell and excrete it into the culture medium. The effects of incubation time, lysine concentration, and carbon and nitrogen sources on AASA production were examined. In the presence of 15 g glucose/1, 1.25 g NH4H2PO4/l and 50 mg l-lysine/l in a minimal salt medium C. maltosa G285 (lys1) produced about 80–90 mg AASA/l during 48 h of growth. A simple and rapid procedure to isolate AASA from the medium using Dowex 50X4 is described. 相似文献
9.
Heritability, phenotypic and genetic correlations of egg characteristics of Japanese quail were investigated to obtain basal information on breeding, strain identification and genetic monitoring. For this study, 3230 eggs produced from 323 female were used. Measurement were taken on egg weight, yolk weight, albumen weight, shell weight, egg shape index, albumen height, specific gravity, shell thickness, shell strength and yolk color. Heritability estimates of egg characteristics were high and ranged from 0.62 to 0.84. Diverse phenotypic and genetic correlations were observed among egg characteristics. These results indicate that individual selection should be the most efficient method of improving egg characteristics and that consideration should be given to the interrelationship of characteristics to accomplish genetic improvement. The possibility exists these assays of egg characteristics can be used for strain identification and genetic monitoring without killing an individual of quail. 相似文献
10.
Neonatal polycythemia is a perinatal complication in infants of diabetic mothers. The cord CBC (complete blood counts), serum iron, transferrin and ferritin concentrations were studied in newborn infants of 9 GDM (gestational diabetes), 21 NIDDM (noninsulin-dependent diabetes mellitus), and 8 IDDM (insulin-dependent diabetes mellitus) mothers. The RBC (red blood cell) count, Hb (hemoglobin) and Hct (hematocrit) of these infants were higher than control infants. There was no difference between the serum iron concentration of the infants of each group diabetic mothers and the infants in the control group, but the transferrin concentration was significantly higher and the ferritin was significantly lower in the infants of diabetic mothers than in those of control mothers. There was a significant negative correlation between transferrin and ferritin (r = -0.491 p less than 0.001). Erythropoiesis is considered to be enhanced in the fetuses of diabetic mothers, and the iron needed for erythropoiesis is reportedly transported from the mother to the fetus according to the demands of the fetus, but the iron storage was shown to be reduced in the fetuses of diabetic mothers. 相似文献