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41.
Brunella Franco Li-Wen Lai David Patterson David H. Ledbetter Barbara J. Trask Ger van den Engh Susan Iannaccone Shannon Frances Pragna I. Patel James R. Lupski 《Human genetics》1991,87(3):269-277
Summary We report a patient (S.T.) with multiple congenital anomalies and developmental delay associated with an interstitial deletion of 1q23–1q25. Molecular analysis of the deletion was performed using DNA markers that map to 1q. Five DNA markers, MLAJ-1 (D1S61), CRI-L1054 (D1S42), HBI40 (D1S66), OS-6 (D1S75), and BH516 (D1S110), were demonstrated to be deleted. Informative polymorphisms demonstrated this to be a de novo deletion of the maternally derived chromosome. Deletion status was determined using restriction fragment length polymorphism (RFLP) analysis supplemented with densitometry in the experiments where RFLP analysis was not fully informative. Deletions were confirmed by Southern analysis using genomic DNA from a somatic cell hybrid retaining the del(1)(q23–q25) chromosome that was constructed from patient S.T. Flow karyotyping confirmed the deletion and estimated that the deletion encompassed 11,000–16,000 kb. The clinical and cytogenetic characteristics of S.T. are compared with those of ten previously described patients with monosomy 1q21–1q25. 相似文献
42.
43.
N J Parsons A A Kwaasi P V Patel C A Nairn H Smith 《Journal of general microbiology》1986,132(12):3277-3287
A protein of about 20 kDa was extracted by sodium cholate (1%, w/v) from outer membranes of a strain of Neisseria gonorrhoeae, BS4 (agar), which is resistant to killing by human phagocytes. When the protein was purified by repeated fractionation on Sephadex G75, contamination with other outer-membrane proteins and lipopolysaccharide was negligible. The protein contained a full complement of amino acids, with high levels of glutamic acid. Carbohydrate, detected by the anthrone method and by sugar and hexosamine analysis, was present, but at very low levels. There was a significant content of fatty acids (about 5.7% of the protein), indicating a lipoprotein. The 20 kDa lipoprotein: (1) neutralized the ability of antiserum against whole organisms of BS4 (agar) to reduce the resistance of this strain to phagocyte killing; (2) evoked in mice an antiserum which reduced this resistance and immunoblotted only with 20 kDa lipoprotein in the cholate extract of outer membranes; and (3) promoted resistance to intracellular killing of an otherwise phagocyte susceptible gonococcal strain (BSSH). This is strong evidence that it is a determinant of gonococcal resistance to phagocyte killing. 相似文献
44.
Sequence-dependent conformation of DNA duplexes. The AATT segment of the d(G-G-A-A-T-T-C-C) duplex in aqueous solution 总被引:3,自引:0,他引:3
The nonexchangeable base and sugar protons of the octanucleotide d(G-G-A-A-T-T-C-C) have been assigned by two-dimensional correlated (COSY) and nuclear Overhauser effect (NOESY) methods in aqueous solution. The assignments are based on distance connectivities of less than 4.5 A established from NOE effects between base and sugar protons on the same strand and occasionally between strands, as well as, coupling connectivities within the protons on each sugar ring. We observe the NOEs to exhibit directionality and are consistent with the d(G-G-A-A-T-T-C-C) duplex adopting a right-handed helix in solution. The relative magnitude of the NOEs between base and sugar H2' protons of the same and 5'-adjacent sugars characterizes the AATT segment to the B-helix type in solution. 相似文献
45.
Mottling phenomena and quality of grains of different genotypes of Durum wheat grown under limited irrigation conditions 总被引:1,自引:0,他引:1
Summary Field experiment was conducted to show the effect of one irrigation of 10 cm water applied to durum wheat (Triticum durum) at crown root initiation stage, active tillering stage, anthesis stage and compared them with non irrigated plot using A-206, A-28, A-1-8-8-42-1, G.W.-1 and A-23-10 genotypes under the conditions of salt affected areas having shallow saline aquifer, on quality, yield and mottling phenomena in wheat grain. Application of irrigation significantly increased the yield and decreased the per cent mottled grain and the maximum achievement was obtained when water was applied during the stage of anthesis. Non mottled grain contained higher protein than mottled grain and there were no considerable differences in other biochemical constituents. Genotype G.W.-1 stands first in its yield performance and low mottled grain. 相似文献
46.
Summary Free-proline accumulation was measured in leaves of intact wheat (Triticum vulgare L. cv. Kalyan Sona), plantago (Plantago ovata Forsk-Isabgool), papavar (Papaver somnifera L. Opium poppy) and mustard (Brassica juncea L. var. Varuna) grown in the field with low to high field water content and thus they were subjected to water stress. Leaf water deficit in percentage was used to determine the degree of stress at the time of proline anlysis.Free proline content was higher in mustard leaves as compared to wheat, plantago and papavar leaves. Water stress enhances the proline content but at same water deficit level the content differ in the leaves of the plants studied. 相似文献
47.
Rats are known to respond to a cold stimulus by increasing the activity and amount of the uncoupling protein in brown adipose tissue. A 48 h cold stimulus was found to increase the synthesis of uncoupling protein 3.g-fold in 4–5 week old rats whereas no change was observed with newborn rabbits. The lack of response in the latter case may reflect a difference between rabbits and rats or that synthesis is already maximal in newborn rabbits. 相似文献
48.
Thermophilic anaerobic spirochetes in New Zealand hot springs 总被引:1,自引:0,他引:1
Abstract Electron and light microscopy revealed the presence of spirochetes in New Zealand thermal springs. The spirochete population in one spring studied (Kuirau Lake) was affected by fluctuations in temperature and/or pool level. A pure culture of the strictly anaerobic bacterium revealed that it grew optimally at a temperature of 45–50°C, with no growth occurring above 60°C, and a pH of 7.0–7.5 with no growth occurring at pH 5.5 or 8.5. Growth was inhibited by chloramphenicol, penicillin, streptomycin, tetracycline and neomycin but not by d -cycloserine, novobiocin or phosphomycin at 10 μg/ml. A wide range of carbohydrates were utilized but not organic acids. Acetate was the major end product of glucose fermentation with substantial amounts of ethanol and traces of lactate being produced. 相似文献
49.
Abstract An anaerobic ethanologenic strain of extremely thermophilic bacteria isolated from a New Zealand hot spring resembled Thermoanaerobium brockii in morphology and cell-wall ultrastructure. However, antibodies produced against the New Zealand isolate did not crossreact with the type strain of T. brockii . The New Zealand isolate strain Tok6-B1 fermented a wider range of carbohydrate substrates, including pentoses, and was less inhibited by a hydrogen atmosphere. Ethanol and acetate were major end-products and lactate a minor product of glucose fermentation. Under a hydrogen atmosphere, these 3 end-products were formed in approximately equal amounts. 相似文献
50.
The stimulation of hepatic gluconeogenesis by acetoacetate precursors. A role for the monocarboxylate translocator 总被引:1,自引:0,他引:1
The regulation of the gluconeogenic pathway from the 3-carbon precursors pyruvate, lactate, and alanine was investigated in the isolated perfused rat liver. Using pyruvate (less than 1 mM), lactate, or alanine as the gluconeogenic precursor, infusion of the acetoacetate precursors oleate, acetate, or beta-hydroxybutyrate stimulated the rate of glucose production and, in the case of pyruvate (less than 1 mM), the rate of pyruvate decarboxylation. alpha-Cyanocinnamate, an inhibitor of the monocarboxylate transporter, prevented the stimulation of pyruvate decarboxylation and glucose production due to acetate infusion. With lactate as the gluconeogenic precursor, acetate infusion in the presence of L-carnitine stimulated the rate of gluconeogenesis (100%) and ketogenesis (60%) without altering the tissue acetyl-CoA level usually considered a requisite for the stimulation of gluconeogenesis by fatty acids. Hence, our studies suggest that gluconeogenesis from pyruvate or other substrates which are converted to pyruvate prior to glucose synthesis may be limited or controlled by the rate of entry of pyruvate into the mitochondrial compartment on the monocarboxylate translocator. 相似文献