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1.
C Julien C Barres P Kandza J Sassard 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1989,308(8):219-222
Intra-aortic blood pressure (BP) was measured in conscious rats after early chronic destruction of the peripheral sympathetic nervous system (SNS) with guanethidine. In sympathectomized rats, the mean level of BP was not different from that of control rats but its variability was markedly increased. These results indicate that functional integrity of the SNS is of primary importance for the short-term control of BP but is not essential for its long-term maintenance. 相似文献
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Y Ma B I Wilson S Bijvoet H E Henderson E Cramb G Roederer M R Ven Murthy P Julien H D Bakker J J Kastelein 《Genomics》1992,13(3):649-653
We have previously reported two common lipoprotein lipase (LPL) gene mutations underlying LPL deficiency in the majority of 37 French Canadians (Monsalve et al., 1990. J. Clin. Invest. 86: 728-734; Ma et al., 1991. N. Engl. J. Med. 324: 1761-1766). By examining the 10 coding exons of the LPL gene in another French Canadian patient, we have identified a third missense mutation that is found in two of the three remaining patients for whom mutations are undefined. This is a G to A transition in exon 6 that results in a substitution of asparagine for aspartic acid at residue 250. Using in vitro site-directed mutagenesis, we have confirmed that this mutation causes a catalytically defective LPL protein. In addition, the Asp250----Asn mutation was also found on the same haplotype in an LPL-deficient patient of Dutch ancestry, suggesting a common origin. This mutation alters a TaqI restriction site in exon 6 and will allow for rapid screening in patients with LPL deficiency. 相似文献
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Acetylcholinesterase is found in the brush-border and basolateral membranes purified from rabbit enterocytes. The sedimentation coefficients of the enzymes solubilized from two types of membrane are identical (5.5 +/- 0.2 S) and the apparent molecular weights are not significantly different (154 000 +/- 8000 for the brush-border and 145 000 +/- 8000 for the basolateral membrane enzyme). These results suggest a unique G2 molecular form for acetylcholinesterase from brush-border as well as from basolateral membranes. 相似文献
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We have cloned a cDNA coding for the smallest rat neurofilament protein. The cDNA is 861 nucleotides long coding for 287 amino acids from the internal alpha-helical region and the carboxy-terminal tail domain of the neurofilament protein. Comparison of the porcine, mouse and rat neurofilament protein sequences shows that the protein is highly conserved (greater than 93% identity). Blot analysis indicates that the cDNA is derived from a single neurofilament gene that codes for two different poly(A)+ mRNA species. 相似文献
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Gauthier Janel Lacroix Renée Coté Alain Doyon Julien Drolet Michel 《Applied psychophysiology and biofeedback》1985,10(2):139-159
In order to assess the relative effectiveness of finger warming and temporal blood volume pulse reduction biofeedback in the treatment of migraine, 22 female migraine patients were assigned to one of three experimental conditions: temporal artery constriction feedback, finger temperature feedback, or waiting list. Biofeedback training consisted of 12 sessions over a 6-week period. All patients completed 5 weeks of daily self-monitoring of headache activity (frequency, duration, and intensity) and medication before and after treatment. Treatment credibility was assessed at the end of Sessions 1, 6, and 12. Results showed that temporal constriction and finger temperature biofeedback were equally effective in controlling migraine headaches and produced greater benefits than the waiting list condition. Power analyses indicated that very large sample sizes would have been required to detect any significant differences between the two treatment groups. No significant relationships were found between levels of therapeutic gains and levels of thermal or blood volume pulse self-regulation skills. Likewise, treatment outcome was not found to be related to treatment credibility. Further analyses revealed that changes in headache activity and medication were associated with changes in vasomotor variability. Because blood volume pulse variability was not significantly affected by biofeedback training, questions about its role in the therapeutic mechanism are raised.This research was supported in part by grants from the Quebec Ministry of Education and the Quebec Ministery of Social Affairs to the first author, and an award from the Medical Research Council of Canada to the second author. The authors are indebted to Drs. Frank Andrasik, Howard Barbaree, Edward Blanchard, Martin Ford, and Patrick McGrath, as well as to two anonymous reviewers, for their helpful comments on an earlier draft of this paper. 相似文献
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The distribution of phosphorylation sites among identified proteolytic fragments of mammalian neurofilaments 总被引:32,自引:0,他引:32
Neurofilaments were treated with chymotrypsin or with Staphylococcus aureus V8 protease (V8 protease) and the proteolytic fragments in soluble and particulate centrifugal fractions were identified by immune blotting, using antibodies raised against the Mr = 68,000 (P68), 145,000 (P145), and 200,000 (P200) subunits. The data provide further evidence that each of the three subunits has a different disposition within the filament. A Mr = 160,000 fragment of P200, which may correspond to the side arm projections on neurofilaments, was released into solution by chymotrypsin. In contrast, the proteolytic fragments of P68 and P145 were recovered mainly in the particulate centrifugal fraction, indicating that the two subunits are more closely associated with the filament backbone. Proteolytic cleavage studies on neurofilaments that were 32P-labeled in vivo indicated that the phosphorylated domains in P200 and P145 are localized in a restricted segment of each subunit, which occurs between the chymotryptic and V8 protease cleavage sites. No 32P was associated with the bulk of chymotryptic fragments, which are found in the particulate fraction, are about 40,000 daltons in size, and derive from all three neurofilament subunits. Most of the phosphorylation sites in neurofilaments are peripherally located in the projection domain of P200, suggesting that phosphorylation may modulate interactions between neurofilaments and other neuronal components. 相似文献