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排序方式: 共有965条查询结果,搜索用时 15 毫秒
921.
J. H. Pennington N. H. Brooksbank Pauline M. Poole F. Seymour 《BMJ (Clinical research ed.)》1968,4(5634):804-806
In tracing the source of an outbreak of food-poisoning with Salmonella virchow a chicken-packing station and associated rearing farms were investigated. The serotype was found in chickens in 9 of the 14 rearing farms investigated and in the hatchery, but not in the breeding flocks supplying the hatchery. Several personnel on the farms were affected. The infection was most likely to have been introduced by contaminated feeding-stuffs. 相似文献
922.
Skeletal myotubes responded to passive stretch by increased amino acid uptake (as measured with [3H]α-aminoisobutyric acid), increased incorporation of amino acids into total cellular protein and myosin heavy chains, and increased accumulation of total cellular protein and myosin heavy chains. These alterations were preceded by an increase in the uptake of ouabain-sensitive rubidium-86 (86Rb+), a potassium tracer used to measure membrane sodium pump activity (Na+K+ATPase). This stretch-induced stimulation of 86Rb+ uptake resulted from a 60-70% increase in the Vmax of the Na pump with little change in the Km. [3H] ouabain binding studies showed no stretch-induced change in the number of membrane Na pumps, indicating that stretch activates the Na pumps that are already present on the cell surface. Since the stretch-induced increases in amino acid transport and amino acid incorporation into proteins were inhibited by ouabain, Na pump activation may be involved in stretch-induced cell growth of skeletal muscle cells by hypertrophy. 相似文献
923.
Mildred K. Fleetwood Roy F. Davis Seymour Bakerman 《Preparative biochemistry & biotechnology》2013,43(1):205-220
The objectives of this research were to separate and partially characterize the components of rat liver cell plasma membranes. The plasma membranes of liver cells obtained from normal Wistar male rats were isolated using density gradients. The purified membrane was then solubilized in phenol-urea-acetic acid and gel electrophoresis was performed on the solubilized membrane components. Samples of the eluate collected following preparative gel electrophoresis were phosphorus positive-ninhydrin positive; phosphorus negative-ninhydrin positive; phosphorus po6itive-ninhydrin negative; and phosphorus negative-ninhydrin negative. The amino acid analyses showed that the proteins of the separated components were different and that no one component contained more than 6% of the total membrane protein. Liver cell plasma membranes contain components that differ from those of red blood cell plasma membranes. These components can be further divided into subgroups of proteins, i.e., phospholipoproteins and protein alone. The concept of a group of proteins composing the membrane is extended to one of various subgroups on the basis of their different affinity for lipid. 相似文献
924.
Fred R. Seymour 《Carbohydrate research》1974,34(1):65-70
The unambiguous syntheses of methyl 3,4,6-tri-O-methyl-α-d-mannopyranoside (6) and methyl 3,4-di-O-methyl-α-d-mannopyranoside (10) were performed by routes involving methyl 3-O-benzoyl-4,6-O-benzylidene-α-d-mannopyranoside (1) to form methyl 2-O-p-tolylsulfonyl-d-mannopyranoside (4). Compound 4 directly led to 6, and, via a 6-trityl derivative, to 10. 相似文献
925.
926.
A. Garm M. M. Coates R. Gad J. Seymour D. -E. Nilsson 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2007,193(5):547-557
Box jellyfish, or cubomedusae, possess an impressive total of 24 eyes of four morphologically different types. Compared to
other cnidarians they also have an elaborate behavioral repertoire, which for a large part seems to be visually guided. Two
of the four types of cubomedusean eyes, called the upper and the lower lens eye, are camera type eyes with spherical fish-like
lenses. Here we explore the electroretinograms of the lens eyes of the Caribbean species, Tripedalia cystophora, and the Australian species, Chiropsalmus sp. using suction electrodes. We show that the photoreceptors of the lens eyes of both species have dynamic ranges of about 3
log units and slow responses. The spectral sensitivity curves for all eyes peak in the blue-green region, but the lower lens
eye of T. cystophora has a small additional peak in the near UV range. All spectral sensitivity curves agree well with the theoretical absorbance
curve of a single opsin, strongly suggesting color-blind vision in box jellyfish with a single receptor type. A single opsin
is supported by selective adaptation experiments. 相似文献
927.
Twenty-one isolates of Achlya with smooth-walled oogonia, small, eccentric oospores, and a preponderance of monoclinous antheridial branches are characterized quantitatively and qualitatively. The isolates are separated into nine series, and the parameters through which they relate to and digress from one another are discussed. At most, three quantitative characteristics separate the various groups. The distinctive features of isolates in two series are unstable in culture. A concept of broad species limits is applied to A. americana. 相似文献
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