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91.
92.
P J Prichard D Rubinstein D B Jones F J Dudley R A Smallwood W J Louis N D Yeomans 《BMJ (Clinical research ed.)》1985,290(6468):601-603
Healing of duodenal ulcers was assessed in 66 patients who received omeprazole either 10 mg or 30 mg daily for four weeks in a double blind study. Healing was rapid in both groups. At two weeks the ulcers in 15 of the 30 patients taking 10 mg daily had healed compared with 28 of the 36 (78%) taking 30 mg daily (p less than 0.03). At four weeks the respective proportions had risen to 83% (25/30) and 94% (33/35) (p greater than 0.05). In non-smokers the proportion of ulcers healed did not differ significantly with the two doses, although there was a trend for less healing at two weeks with 10 mg daily; in smokers significantly fewer ulcers (p less than 0.05) were healed with 10 mg than 30 mg daily at two weeks (7/16 (44%) v 17/21 (81%] and at four weeks (12/16 (75%) v all 21 (100%]. Adverse reactions were few and transient and were considered unlikely to be due to omeprazole. 相似文献
93.
94.
Sharrock RA Rubinstein S Chan M Leighton T 《Molecular & general genetics : MGG》1984,194(1-2):260-264
Summary A collection of intergenic suppressors of the Bacillus subtilis spoOF221 mutation has been isolated. One of these suppressors, rvtA, has been mapped between lys-1 and aroD. The rvtA suppressor restores spoOF sporulation to wild type levels and substantially improves the sporulation efficiencies of spoOB and spoOE strains. The rvtA gene does not affect the Spo phenotype of spoOH, spoOJ or spoOK mutants. The rvtA gene also prevents the induction by aliphatic alcohols of SpoO phenocopies in wild type B. subtilis cells. 相似文献
95.
Jan-Ingmar Flock Ian Fotheringham Janice Light Les Bell Roger Derbyshire 《Molecular & general genetics : MGG》1984,195(1-2):246-251
Summary A chemically synthesised gene coding for human urogastrone which was earlier cloned in E. coli (Smith et al. 1982) has now been cloned into expression vectors for Bacillus subtilis
Two types of constructs have been made, one giving production of methionylurogastrone and the other giving rise to a methionyl-urogastrone- galactosidase fusion polypeptide facilitating quantification of expression levels.The ribosome binding sites used in the expression plasmids are synthetically made oligonucleotides residing on short restriction fragments to allow easy replacement by other ribosome binding sites.Using shuttle vectors and constitutive promoters from Bacillus phages 105 and SPP1, we were able to detect levels of expression amounting to a few thousand molecules per cell during logarithmic growth in both E. coli and B. subtilis. 相似文献
96.
A monoclonal antibody, 2B6, has been prepared against the embryonic myosin heavy chain of rat skeletal muscle. On solid phase radioimmunoassay, 2B6 shows specificity to myosin isozymes known to contain the embryonic myosin heavy chain and on immunoblots of denatured contractile proteins and on competitive radioimmunoassay, it reacts only with the myosin heavy chain of embryonic myosin and not with the myosin heavy chain of neonatal or adult fast and slow myosin isozymes or with other contractile or noncontractile proteins. This specificity is maintained with cat, dog, guinea pig, and human myosins, but not with chicken myosins. 2B6 was used to define which isozymes in the developing animal contained the embryonic myosin heavy chain and to characterize the changes in embryonic myosin heavy chain in fast versus slow muscles during development. Finally, 2B6 was used to demonstrate that thyroid hormone hastens the disappearance of embryonic myosin heavy chain during development, while hypothyroidism retards its decrease. This confirmed our previous conclusion that thyroid hormones orchestrate changes in isozymes during development. 相似文献
97.
The release of GABA induced by veratridine shows no correlation with the synaptosomal Ca content and is therefore not mediated by the release of mitochondrial Ca. Instead, with both Ca-repleted and -depleted synaptosomes, the extent of GABA efflux is correlated with the decrease in plasma membrane potential. The slow release of GABA induced by protonophores and the Ca-dependent release induced by ionophore A23187 are also consequences of the depolarization of the plasma membrane, rather than of elevated cytosolic Ca. Finally, the ability of verapamil to inhibit the release of GABA induced by low veratridine concentrations is due to the ability of the Ca channel inhibitor to antagonize the action of veratridine, rather than to inhibit Ca entry into the synaptosome. It is concluded that it is essential to monitor plasma membrane potentials in experiments in which amino acid efflux from synaptosomes is induced. 相似文献
98.
Characterization of Cholecystokinin from the Human Brain 总被引:1,自引:0,他引:1
Laurence J. Miller Ian Jardine† Edward Weissman Vay Liang W. Go David Speicher‡ 《Journal of neurochemistry》1984,43(3):835-840
Human forms of cholecystokinin have not previously been characterized chemically. In this study, we have extracted and purified the predominant molecular form of cholecystokinin present in human cerebral cortex. The peptide was characterized by amino acid analysis, automated peptide sequencing, and fast atom bombardment mass spectrometry. It appears to be identical to porcine cholecystokinin-octapeptide, with the sequence of Asp-Tyr(SO3)-Met-Gly-Trp-Met-Asp-Phe(NH2). This structural identity is consistent with the observations that the peptide in human brain and porcine cholecystokinin-octapeptide are recognized similarly by a battery of antisera to porcine cholecystokinin; that they coelute from several chromatographic systems, including gel filtration, ion exchange, and reversed-phase; and that they possess similar biological activities. 相似文献
99.
S A Vinores M M Herman L J Rubinstein P J Marangos 《The journal of histochemistry and cytochemistry》1984,32(12):1295-1302
The cellular distribution and intracellular localization of neuron-specific enolase (NSE) has been studied by electron microscopic immunocytochemistry in the brain of the rat and of the mouse. Although the intensity of staining was less in the mouse, the same structures were positive in both species. In the cerebrum, the neuronal perikarya and dendrites were intensely stained, but staining was almost entirely absent in the presynaptic terminals. The deep neurons of the brain stem were also positive. In the cerebellum, perikarya, axons, and parallel fibers of the granule cell neurons were stained as were the synaptic vesicles and presynaptic membranes of the synapses between the parallel fibers and the Purkinje cell dendrites. Golgi cell dendrites, basket cells and their axons, and mossy fibers were also positive. In contrast, the Purkinje cells including their dendrites, and the climbing fibers that formed synapses with the Purkinje cell dendrites were not stained. The majority of the myelinated axons in both the cerebrum and the cerebellum did not stain, but the fibrillary astrocytic processes between myelinated axons in the white matter did. Oligodendroglia, protoplasmic astrocytes, Bergmann glia, astrocytes investing capillaries, and vascular endothelial cells were negative for reaction product. In the positively staining cells and their processes, the positivity was dispersed throughout the cytoplasm and corresponded most closely to the distribution of ribosomes, the granular endoplasmic reticulum, and microtubules. Nuclei, mitochondria, the cisternae of the Golgi complex, myelin lamellae, and most membranes were not stained. 相似文献
100.
Effect of mouthpiece, noseclips, and head position on airway area measured by acoustic reflections 总被引:1,自引:0,他引:1
Rubinstein I.; McClean P. A.; Boucher R.; Zamel N.; Fredberg J. J.; Hoffstein V. 《Journal of applied physiology》1987,63(4):1469-1474
To investigate whether it is possible to simplify the methodology of measuring airway area by acoustic reflections, we measured upper airway area in 10 healthy subjects during tidal breathing according to seven different protocols. Three protocols employed custom-made bulky mouthpiece with or without nose-clips, two protocols used a scuba-diving mouthpiece and cotton balls placed in the nostrils instead of noseclips, and two protocols employed neck flexion and extension. We found no significant difference in average pharyngeal, glottic, and tracheal areas for any of the protocols except for neck flexion, which was associated with a significantly lower mean pharyngeal area. Intraindividual variabilities were comparable for all protocols, except for protocol employing the customary bulky mouthpiece and no noseclips, which consistently resulted in the most variable measurements of area for all three airway segments: pharynx, glottis, and trachea. Furthermore, we found that the protocol employing the scuba-diving mouthpiece with or without cotton balls in the nostrils resulted in the lowest number of unacceptable measurements. We conclude that measurements of airway area by acoustic reflections may be further simplified by using a scuba-diving mouthpiece without noseclips; furthermore, control of head position during measurements is not critical provided there is no obvious neck flexion. 相似文献