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91.
92.
A primary linkage map of the domestic turkey (Meleagris gallopavo) was developed by segregation analysis of genetic markers within a backcross family. This reference family includes 84 offspring from one F1 sire mated to two dams. Genomic DNA was digested using one of five restriction enzymes, and restriction fragment length polymorphisms were detected on Southern blots using probes prepared from 135 random clones isolated from a whole-embryo cDNA library. DNA sequence was subsequently determined for 114 of these cDNA clones. Sequence comparisons were done using BLAST searches of the GenBank database, and redundant sequences were eliminated. High similarity was found between 23% of the turkey sequences and mRNA sequences reported for the chicken. The current map, based on expressed genes, includes 138 loci, encompassing 113 loci arranged into 22 linkage groups and an additional 25 loci that remain unlinked. The average distance between linked markers is 6 cM and the longest linkage group (17 loci) measures 131 cM. The total map distance contained within linkage groups is 651 cM. The present map provides an important framework for future genome mapping in the turkey. 相似文献
93.
Kayser Bengt; Favier Roland; Ferretti Guido; Desplanches Dominique; Spielvogel Hilde; Koubi Harry; Sempore Brigitte; Hoppeler Hans 《Journal of applied physiology》1996,81(6):2488-2494
Kayser, Bengt, Roland Favier, Guido Ferretti, DominiqueDesplanches, Hilde Spielvogel, Harry Koubi, Brigitte Sempore, and HansHoppeler. Lactate and epinephrine during exercise in altitudenatives. J. Appl. Physiol. 81(6):2488-2494, 1996.We tested the hypothesis that the reported lowblood lactate accumulation ([La]) during exercise inaltitude-native humans is refractory to hypoxia-normoxia transitions byinvestigating whether acute changes in inspiredO2 fraction(FIO2) affect the[La] vs. power output ()relationship or, alternatively, as reported for lowlanders, whetherchanges in [La] vs. on changes inFIO2 are related tochanges in blood epinephrine concentration ([Epi]). Altitude natives [n = 8, age 24 ± 1 (SE) yr, body mass 62 ± 3 kg, height 167 ± 2 cm]in La Paz, Bolivia (3,600 m) performed incremental exercise with twolegs and one leg in chronic hypoxia and acute normoxia (AN). Submaximalone- and two-leg O2 uptake (O2) vs. relationships were not altered byFIO2. AN increased two-legpeak O2 by 10% and peak by 7%. AN paradoxically decreasedone-leg peak O2 by 7%,whereas peak remained the same. The[La] vs. relationships were similar tothose reported in unacclimatized lowlanders. There was a shift to theright on AN, and maximum [La] was reduced by 7 and 8% forone- and two-leg exercises, respectively. [Epi] and[La] were tightly related (mean r = 0.81) independently ofFIO2. Thus normoxiaattenuated the increment in both [La] and [Epi]as a function of , whereas the correlation between[La] and [Epi] was unaffected. These data suggest loose linkage of glycolysis to oxidative phosphorylation under influence from [Epi]. In conclusion, high-altitudenatives appear to be not fundamentally different from lowlanders with regard to the effect of acute changes inFIO2 on [La] during exercise. 相似文献
94.
Harry Walter Gerard B. Nash Galli S. Ascher Herbert J. Meiselman 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1996,680(1-2):197-200
Counter-current distribution (CCD) of red blood cells (RBC) from individuaks with homozygous sickle cell (HbSS) disease in a charge-sensitive aqueous dextran-poly(ethylene glycol) phase system, which fractionates cells on the basis of surface properties, indicates that the percentage of irreversibly sickled cells (ISC) increases and the percentage of reticulocytes decreases with increasing cell partition ratios. The high partition ratios of ISC correspond to those of older RBC when RBC from normal individuals are subjected to CCD. Our results thus indicate that ISC differ in surface properties from those of the bulk of sickle RBC (including reticulocytes) in the population and that the difference is, most likely, charge-related. While the question as to whether ISC are indeed old cells has not yet been unequivocally answered, this view finds support in the fact that the independent parameters of ISC surface properties, as reflected by partition ratios, and densities correlate as they do in older RBC from normal individuals. 相似文献
95.
96.
97.
Long-term field experiments in Norway spruce stands on fertile sites (site indices 27–35 m) in southwestern Sweden were analysed with respect to volume increment. Three treatments were included (0=No fertilization, N = Fertilization with N, NP = Fertilization with N and P).Volume growth was monitored for 18 years in 10 blocks. No significant differences in annual volume increment between the treatments were detected. Volume increments in the N treatment were 97%, 99% and 107% as high as those in the 0 treatment for the periods 1–5, 6–10 and 11–15 years after the first fertilization. Corresponding values for the NP treatment were 104%, 108% and 110%, indicating that P has a small positive effect.The amount of N-fertilization would correspond to an annual N deposition of 20 kg ha-1 during the next 30 years in southwestern Sweden. For this period, the results imply that this N deposition would not affect the growth of Norway spruce stands on fertile sites. 相似文献
98.
Filamentous fungi are capable of secreting relatively large amounts of heterologous recombinant proteins. Recombinant human glycoproteins expressed in this system, however, carry only carbohydrates of the oligomannose type limiting their potential use in humans. One approach to the problem is genetic engineering of the fungal host to permit production of complex and hybrid N-glycans. UDP-GlcNAc:3-d-mannoside -1,2-N-acetylglucosaminyltransferase I (GnT I) is essential for the conversion of oligomannose to hybrid and complex N-glycans in higher eukaryotic cells. Since GnT I is not produced by fungi, we have introduced into the genome ofAspergillus nidulans the gene encoding full-length rabbit GnT I and demonstrated the expression of GnT I enzyme activity at levels appreciably higher than occurs in most mammalian tissues. All the GnT I activity in theAspergillus transformants remains intracellular suggesting that the rabbit trans-membrane sequence may be capable of targeting GnT I to the fungal Golgi apparatus.Abbreviations CM
complete medium
- Gal-T
UDP-Gal:GlcNAc -1,4-galactosyltransferase (EC 2.4.1.38/90)
- GnT I
UDP-GlcNAc:3-d-mannoside -1,2-N-acetylglucosaminyltransferase I (EC 2.4.1.101)
- HPLC
high performance liquid chromatography
- M3-octyl
Man1-6[Man1-3]Man-octyl
- PAGE
polyacrylamide gel electrophoresis
- MES
2-(N-morpholino)ethane sulfonate
- PCR
polymerase chain reaction
- PEG
polyethylene glycol
- PMSF
phenyl methyl sulfonyl fluoride
- SDS
sodium dodecyl sulfate
- SSC (1×)
0.15m NaCl/0.015m sodium citrate (pH 7.0)
- STC
1.2m sorbitol, 100mm Tris-HCl, pH 7.4, and 10mm CaCl2
- STET
0.1m NaCl, 10mm Tris-HCl, pH 8.0, 1mm EDTA, pH 8.0, 5% Triton-X-100
Deceased. This paper is dedicated to the memory of Lorne S. Reid. 相似文献
99.
Salem Faham Tadashi J. Mizoguchi Elinor T. Adman Harry B. Gray John H. Richards D. C. Rees 《Journal of biological inorganic chemistry》1997,2(4):464-469
Replacement of the cysteine at position 112 of Pseudomonas aeruginosa azurin with an aspartic acid residue results in a mutant (Cys112Asp) protein that retains a strong copper-binding site. CuII(Cys112Asp) azurin can be reduced by excess [RuII(NH3)6]2+, resulting in a CuI protein with an electronic absorption spectrum very similar to that of wild-type CuI azurin. Cys112Asp azurin exhibits reversible interprotein electron-transfer reactivity with P. aeruginosa cytochrome c 551 (μ?=?0.1?M sodium phosphate (pH?7.0);E°(CuII/I)?=?180 mV vs NHE); this redox activity indicates that electrons can still enter and exit the protein through the partially solvent-exposed imidazole ring of His117. The structure of CuII(Cys112Asp) azurin at 2.4-Å resolution shows that the active-site copper is five coordinate: the pseudo-square base of the distorted square-pyramidal structure is defined by the imidazole Nδ atoms of His46 and His117 and the oxygen atoms of an asymmetrically-bound bidentate carboxylate group of Asp112; the apical position is occupied by the oxygen atom of the backbone carbonyl group of Gly45. The CuII–Asp112 interaction is distinguished by an approximately 1.2-Å displacement of the metal center from the plane defined by the Asp112 carboxylate group. 相似文献
100.
Sato Yoji; Weil Max Harry; Tang Wanchun; Sun Shijie; Xie Jianlin; Bisera Joe; Hosaka Hidehiro 《Journal of applied physiology》1997,82(2):558-562
Sato, Yoji, Max Harry Weil, Wanchun Tang, Shijie Sun,Jianlin Xie, Joe Bisera, and Hidehiro Hosaka. EsophagealPCO2 as a monitor of perfusionfailure during hemorrhagic shock. J. Appl.Physiol. 82(2): 558-562, 1997.Measurement ofgastric wall PCO2(PgCO2) bytonometric method has emerged as an attractive option for estimatingvisceral perfusion during circulatory shock. However, gastric acidsecretion obfuscates the tonometric measurement. We, therefore,investigated the option of measuringPCO2 in the esophagus to minimizethese restraints. Hemorrhagic shock was induced in five Sprague-Dawleyrats, and five rats served as sham controls.PgCO2 wasmeasured with an ion-sensitive field effect transistor that wassurgically implanted into the gastric wall. Esophageal luminalPCO2(PeCO2) wasmeasured by a second ion-sensitive field effect transistor sensor.During hemorrhagic shock, mean aortic pressure declined from 150 to 50 mmHg. Gastric blood flow decreased from 58 to 12 ml · min1 · 100 g1 (21% of preshock) andesophageal blood flow from 44 to 7 ml · min1 · 100 g1 (16% of preshock).PgCO2simultaneously increased from 47 to 116 Torr andPeCO2 from 47 to 127 Torr. The increases inPgCO2 werehighly correlated with increases inPeCO2(r = 0.90). Esophageal tonometry may,therefore, serve as a practical alternative to gastric tonometry. 相似文献