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991.
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
992.
B. Gasser M. Toussaint R. Luthringer J. P. Macher R. Cerf 《Journal of biological physics》1996,22(4):209-225
Attempts to demonstrate low-dimensional attractor behaviour in the analysis of electroencephalographic (EEG) signals meet with difficulties that in part stem from a departure from single-system dynamics. In order to address this problem, the -waves can be extracted by digital filtering or by wave separation; these two techniques are compared in order to specify the conditions in which finite impulse response (FIR) bandpass filters can be used. The comparison was made using 18 EEG records of 3 min duration under resting conditions (6 subjects, 3 records per subject: prior to apomorphine administration, then 90 min and 150 min post-treatment). No presence of low-dimensional dynamic episodes in -signals was observed without digital processing. Sixty 5 s sections showing attractor behaviour were found after filtering and twenty five 5 s sections after wave separation. The mean correlation dimension was calculated for each experimental condition and for 4 subjects, in order to observe the temporal profile of the drug. When attractors were found after wave separation, bandpass filtering then also showed attractor behaviour, with the same temporal profile. However, the reverse is not true: attractors were found after bandpass filtering that were not present after wave separation; in this case the results deserve confirmation, although the temporal profiles for all cases in which attractors were found after filtering remained comparable. 相似文献
993.
Shinichiro Nakamura Wijit Kiatipattanasakul Hiroyuki Nakayama Fumiko Ono Ippei Sakakibara Yasuhiro Yoshikawa Naoaki Goto Kunio Doi 《Journal of medical primatology》1996,25(4):294-300
Abstract: In this study, we immunohistochemically examined the several constituents of senile plaques (SPs) and cerebral amyloid angiopathy (CAA) in aged cynomolgus monkeys. Apolipoprotein E (apoE) deposited in all mature plaques and CAA, and in half of the diffuse plaques. Alpha-1-antichymotripsin (αACT) deposited in half of the mature plaques and in one third of the CAA. Amyloid precursor protein (APP), ubiquitin (Ub), and microtubule-associated protein-2 (MAP-2) accumulated in the swollen neurites of mature plaques. Glial fibrillary acidic protein (GFAP) was detected in the astrocytes and their processes surrounding the mature plaques. Tau was detected in neither the SPs nor CAA. Therefore, mature plaques involved extracellular Aβ, apoE, and αACT, and also astrocytes and swollen neurites. However, diffuse plaques involved only extracellular Aβ and apoE. Since these features, except for tau, were consistent with those in humans, this animal model will be useful for studying the pathogenesis of cerebral amyloid deposition. 相似文献
994.
F. Morishita A. Shimada Y. Takeda M. Fujimoto H. Katayama K. Yamada 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1996,166(8):467-472
To investigate the functions of GTP-binding protein(s) in the melanosome-aggregating response in fish melanophores, the effects
of activators of G-proteins, namely, mastoparan and compound 48/80, were examined in cultured melanophores of the balck-moor
goldfish, Carassius auratus. Both mastoparan and compound 48/80 induced an approximately 40% increase in the GTP-hydrolyzing activity in the melanophore
membranes compared to the basal level. In intact melanophores, these compounds inhibited the effect of 3-isobutyl-1-methylxanthine,
which induced the accumulation of intracellular cAMP. Pretreatment of melanophores with pertussis toxin at 1 μg ⋅ ml-1 for 15 h attenuated the inhibitory effect of mastoparan on the accumulation of cAMP. However, pretreatment with the toxin
only slightly attenuated the inhibitory effect of compound 48/80 on the accumulation of cAMP. In addition, compound 48/80
at 1 mg ⋅ ml-1 induced full aggregation of the melanosomes in melanophores, though mastoparan at 5 μmol ⋅ l-1 induced only 10–20% aggregation of melanophores. These results suggest that mastoparan and compound 48/80 can each activate
the inhibitory G-protein in goldfish melanophores, which results in inhibition of adenylate cyclase activity. This signal-transduction
pathway is involved in the aggregation of melanosomes in these cells.
Accepted: 3 June 1996 相似文献
995.
Robert N. Fontaine Ruanna E. Gossett Friedhelm Schroeder Barbara A. O'Toole Thomas Doetschman Ann B. Kier 《Molecular and cellular biochemistry》1996,159(2):149-153
The effect of transforming growth factor beta-1 (TGF1) expression on fatty acid binding proteins was examined in control and two strains of gene targeted TGF1-deficient mice. Homozygous TGF1-deficient 129 × CF-1, expressing multifocal inflammatory syndrome, had 25% less liver fatty acid binding protein (L-FABP) when compared to control mice. The decrease in L-FABP expression was not due to multifocal inflammatory syndrome since homozygous TGF1-deficient/immunodeficient C3H mice on a SLID background had 36% lower liver L-FABP than controls. This effect was developmentally related and specific to liver, but not the proximal intestine, where L-FABP is also expressed. Finally, the proximal intestine also expresses intestinal-FABP (1-FABP) which decreased 3-fold in the TGF1-deficient/immunodeficient C3H mice only. Thus, TGF1 appears to regulate the expression of L-FABP and I-FABP in the liver and the proximal intestine, respectively.Abbreviations L-FABP
liver fatty acid binding protein
- I-FABP
intestinal fatty acid binding protein
- TGF1
transforming growth factor beta-1
- TNF-
tumor necrosis factor-
- MIP-
macrophage inflammatory protein-
- PMSF
phenylmethyl sulfonyl fluoride
- PBS
phosphate buffered saline 相似文献
996.
In rodents an intravenous administration of viableCryptococcus (C.) neoformans cells frequently resulted in attachment of intravascular cryptococcal granulomas to inner walls of the large to medium-sized
veins of various organs, including the lungs, liver and spleen. In order to elucidate the pathogenesis of granulomatous changes,
the cells composing the intravascular granulomas were observed by electron microscopic peroxidase (PO) cytochemistry. The
granuloma composing cells could be divided into the following four types according to the pattern of endogenous peroxidase
activity: exudate macrophage (Mφ, type I), PO-negative Mφ (type II), resident Mφ (type III) and other inflammatory cells (type
IV). In the intravenous granulomas of the lung, the percentages of composed cells were 39.0% for type I, 57.9% for type II,
0% for type III and 3.1% for type IV. By contrast, in the interstitial granulomas in the lung, type III Mφs, possibly derived
from alveolar Mφs, played a significant role in granuloma formation. This may indicate that the intravascular granuloma is
almost composed of macrophages derived from monocytes rather than alveolar macrophages. The expression of ICAM-1 on endothelia
of the pulmonary veins was examined by immunoelectron microscopy. An immunogold labeling index was significantly augmented
on the surface of endothelia in response to intravenous challenge ofC. neoformans. The intravascular granuloma demonstrates that the monocytes develop into the granuloma-composing macrophages and suppress
the cryptococcal activities even hi the peripheral blood resulting in an assistance of endothelial functions. 相似文献
997.
Ignacio García-De La Torre Mario Salazar-Páramo Gerardo Salmón-De La Torre 《Molecular biology reports》1996,23(3-4):153-157
Mixed connective tissue disease (MCTD) was described as a distinct clinical syndrome in 1972. Since then many cases have been reported in the literature worldwide. In this study we present our experience with a group of 17 Mexican patients with this syndrome, and we analyze their clinical and serological features, as well as the causes of death in these patients. The patients are Mexican mestizos living in Guadalajara and most of them have been followed-up at Hospital General de Occidente for a period of 1–10 years. The female/male ratio was 16:1, and their age ranged from 14–55 years with a mean of 29 years. The disease duration has ranged from 1–17 years, with a mean of 6 years. Among the clinical manifestations we have found a high frequency of lymphadenopathy when compared with published series (13/17 or 76%), and the laboratory findings in our patients included a very high polyclonal increase of gammaglobulins (93%), lymphopenia (76%), direct immunofluorescence speckled nuclear epidermal deposits in skin biopsies (75%) and positive rheumatoid factor (65%). Other clinical and serological features were similar to those reported in other series of patients with MCTD. Six of the 17 patients have died (35%), and in 3 of them (17.5%) the cause of death was due to an infectious disease that suddenly presented, and apparently was not related to a concomitant high dose of steroids or malnutrition in the patients. It seems that in addition to the already well known autoimmune abnormalities that occur in MCTD, there are other features like the presence of lymphadenopathy, the high polyclonal increase of gammaglobulins, and the lymphopenia, that reflect the profound disturbance of the immune system in this syndrome, possibly contributing to the sudden appearance of a severe infectious disease in some of our patients.Abbreviations ANA
antinuclear antibody
- CIE
counterimmunoelectrophoresis
- MCTD
mixed connective tissue disease
- PHA
passive hemagglutination
- PM
polymyositis
- RF
rheumatoid factor
- SLE
systemic lupus erythematosus
- SS
systemic sclerosis (SS) 相似文献
998.
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
999.
One hundred and thirty seven isolates ofCandida species were isolated from antiobiotic associated diarrhoea cases and were examined to study the role ofCandida in the pathogenesis of diarrhoea in infants. The quantitative estimation of yeast population by simple gram stain smear revealed more than 70% of the cases had 3+ score. The isolates further screened for detection of-lactamases. Among the isolatedCandida sp,-lactamases was secreted byC. albicans, C. tropicalis, C. krusei andC. parapsilosis. Further, 46% of theCandida isolates were found to be produced 741–1110 mU/ml of-lactamases, suggesting that these enzyme would inactivate penicillin group of drugs and cause failure in the therapy directed against other diarrhoegenic bacteria.Abbreviation AAD
antibiotic associated diarrhoea 相似文献
1000.
Masayoshi Yamaguchi Reiko Makino Noriaki Shimokawa 《Molecular and cellular biochemistry》1996,165(2):145-150