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971.
Specific molecular marker of the genes controlling linolenic acid content in rapeseed 总被引:4,自引:0,他引:4
C. Jourdren P. Barret D. Brunel R. Delourme M. Renard 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,93(4):512-518
In rapeseed, which is an agronomically important oilseed, variation in the linolenic acid content of the oil has been obtained through chemical mutagenesis treatment. Conventional breeding of this quantitative trait, however requires specific molecular markers. By means of biochemical experiments, we have established that the induced variation in linolenic acid content is associated with the fad3 gene encoding the microsomal 15 desaturase. Using a pair of primers specific to this gene and a doubled haploid progeny derived from a low linolenic x high linolenic acid F1hybrid, we have identified a polymorphism of the fad3 alleles between the low- and the high-linolenic acid genotypes. The structure exon/intron of the fad3 DNA sequence seems to be very similar to that of the Arabidopsis fad3 gene. The choice of the primer pair allows specific amplification of one of the two rapeseed fad3 genes. The value and contribution of specific markers to conventional plant breeding is discussed. 相似文献
972.
C.G. Rodriguez N. Makori M. A. Cukierski A. G. Hendrickx 《Journal of medical primatology》1996,25(2):122-132
Abstract: Formation of the definitive kidney in Macaca fascicularis embryos was investigated using light and electron microscopy. Appearance of the definitive kidney at stage 14 was indicated by the ureteric bud invading the metanephrogenic blastema. Glomerular capillaries originate from the connective tissue that surrounds the developing renal vesicle. At 46–100 days gestational age the more developed glomeruli show thinning of the capillary endothelium, thickening of the basal membrane, and presence of pedicels, suggesting a capability of renal function. 相似文献
973.
H. Schmidt A. Wichmann I. Lamprecht I. Zerbst-Boroffka 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1996,166(3):205-214
Anaerobic metabolism in the limnic annelid Hirudo medicinalis L. was investigated by direct and indirect calorimetry. During long-term severe hypoxia, the rate of heat dissipation was reduced up to 13% of the aerobic rate. At the same time, the rate of ATP turnover was reduced to about 30% of the aerobic rate, indicating that metabolic depression is an important mechanism to ensure survival of the leech during environmental anaerobiosis. Heat dissipation during hypoxia was monitored under two experimental conditions, favouring either concomitant hypocapnia (continuous N2 bubbling) or hypercapnia (self-induced hypoxia). The reduction in heat dissipation during hypocapnic hypoxia was less pronounced than during hypercapnic hypoxia, indicating that the different experimental conditions may influence anaerobic metabolism and the extent of metabolic depression. Biochemical analysis of known anaerobic substrates and endproducts provided the basis for indirect calorimetry during self-induced hypoxia. From changes in metabolites, the expected heat dissipation was calculated for initial (0–8 h) and long-term severe hypoxia (8–72 h). During the initial period, the calculated heat dissipation fully accounted for direct calorimetric determination. During long-term hypoxia, only 71% of the measured heat production could be explained from biochemical analysis of metabolites. Therefore, an additional unknown endproduct cannot be excluded, especially when anaerobic ammonia production and analysis of the carbohydrate balance are considered.Abbreviations
APW
artificial pond water
-
HPLC
high-performance liquid chromatography
-
fw
fresh weight
-
HP
heat production
-
HD
heat dissipation
-
MR
metabolic rate 相似文献
974.
Autoantibodies to SS-A/Ro are among the most common found in sera of patients with systemic rheumatic diseases. These autoimmune diseases can affect various organ systems of the body and are variable in their manifestations and presentation. One of the autoimmune targets is the 60 kDa SS-A/Ro protein known to be associated with small cytoplasmic Y RNAs. To study systematically the expression of the protein, we have cloned the mouse full length 60 kDa SS-A/Ro cDNA using 5′ RACE based on a cDNA sequence reported in the mouse genome project. The recombinant protein derived from the putative full-length construct was shown to react with human prototype anti-SS-A/Ro serum Ge in western blot and immunoprecipitation and comigrated with cellular 60 kDa SS-A/Ro protein in 3T3 cells. Cellular expression, measured by RT-PCR, was highest in mouse brain, followed by lung, muscle, kindney and heart. Lower levels were found in testis, liver and spleen. Like the human 60 kDa SS-A/Ro protein, the deduced mouse homolog has 538 amino acids. Sequence analysis showed 89.9% identity and 95.0% similarity between the mouse and human proteins. 相似文献
975.
Sewage sludge from the Upper Silesia Region of Poland were surveyed for keratinolytic fungi. Out of 100 Petri dishes examined, 89 were positive for these micro-organisms. Altogether, 185 fungal appearances belonging to 10 species were observed. Trichophyton terrestre with its teleomorph Arthroderma quadrifidum, T. ajelloi with A. uncinatum, Microsporum gypseum with Arthroderma sp., and Chrysosporium keratinophilum with Aphanoascus keratinophilus prevailed in the sludges. The sewage treatment technologies together with the sludge structure, humidity and pH were found to be critical factors determining the occurrence of keratinolytic fungi in the sludge environment. The qualitative and quantitative composition of keratinolytic fungi could be a useful tool in evaluation of sludge treatment processes. 相似文献
976.
Masayoshi Yamaguchi Reiko Makino Noriaki Shimokawa 《Molecular and cellular biochemistry》1996,165(2):145-150
977.
Joan E. Vickers Glenn C. Graham Robert J. Henry 《Plant Molecular Biology Reporter》1996,14(4):363-368
Amplification of thebar gene usingTaq DNA polymerase in PCR is often not successful, possibly due tobar's high GC content. We describe a PCR protocol in which reliable amplification at a sensitivity of one gene copy per genome
(in this study, barley) present in the reaction was achieved using a novel pair of primers and Expandtm High Fidelity DNA polymerase mix (Boehringer Mannheim). This method should allow for rapid screening of plants putatively
transformed withbar. 相似文献
978.
Nienow AW Langheinrich C Stevenson NC Emery AN Clayton TM Slater NK 《Cytotechnology》1996,22(1-3):87-94
Because of concern for cell damage, very low agitation energy inputs have been used in industrial animal cell bioreactors, typical values being two orders of magnitude less than those found in bacterial fermentations. Aeration rates are also very small. As a result, such bioreactors might be both poorly mixed and also unable to provide the higher oxygen up-take rates demanded by more intensive operation. This paper reports experimental studies both of K
L
a and of mixing (via pH measurements) in bioreactors up to 8 m3 at Wellcome and of scaled down models of such reactors at Birmingham. Alongside these physical measurements, sensitivity of certain cell lines to continuously controlled dO2 has been studied and the oxygen up-take rates measured in representative growth conditions. An analysis of characteristic times and mixing theory, together with other recent work showing that more vigorous agitation and aeration can be used especially in the presence of Pluronic F-68, indicates ways of improving their performance. pH gradients offer a special challenge. 相似文献
979.
The immunomodulating effects of preoperative sizofiran (SPG) administration on regional lymph nodes were studied in patients
with stage III or IV head and neck cancer, by comparing the immunofunction of peripheral blood. The regional lymph nodes were
dissected surgically, and freshly obtained mononuclear cells were studied to investigate the interleukin-2 (IL-2) production,
the LAK and NK activities, and the quantitative analysis of the surface phenotype of the mononuclear cells. The results indicated
that SPG enhanced immunological activities in the regional lymph nodes, as shown by increased IL-2 production and cytotoxic
activities of the effector cells (NK, LAK), and increased helper T lymphocytes (CD4+) in the tumor-uninvolved lymph nodes. The immunofunction following SPG administration was attenuated, but was still augmented
in the regional lymph nodes with metastases. Therefore, SPG was found to be a biologic response modifier to enhance the immunofunctions
of the regional lymph node in patients with head and neck cancer. 相似文献
980.
A 4-chlorophenol (4-CP)-degrading bacterium, strain CPW301, was isolated from soil and identified as Comamonas testosteroni. This strain dechlorinated and degraded 4-CP via a meta-cleavage pathway. CPW301 could also utilize phenol as a carbon and energy source without the accumulation of any metabolites via the same meta-cleavage pathway. When phenol was added as a additional substrate, CPW301 could degrade 4-CP and phenol simultaneously. The addition of phenol greatly accelerated the degradation of 4-CP due to the increased cell mass. The simultaneous degradation of the 4-CP and phenol is useful not only for enhanced cell growth but also for the bioremediation of both compounds, which are normally present in hazardous waste sites as a mixture. 相似文献