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71.
72.
Leonard Rosenthall 《CMAJ》1964,90(17):999-1004
Experience with 500 radio-chlormerodrin renal scans has shown that the technique can detect (1) altered renal function, both focal and generalized, (2) space-occupying kidney lesions, and (3) renal size and disease in some cases in which the blood urea nitrogen is elevated and the excretory urogram inconclusive.The technique is valuable as an adjunct to the intravenous pyelogram since it may discriminate more disease than was thought to be present or may distinguish between anomalous variations in renal outline and calyceal displacement from parenchymal disease. The technique is completely harmless and there are no known contraindications to the test agent, radio-chlormerodrin. 相似文献
73.
74.
Leonard J. Yamshon 《The Western journal of medicine》1958,89(5):333-334
Frozen shoulder, rare in the young but more easily incurred after age 40, is a result of immobilization from any cause. Atrophy is the first phase, followed by shortening of soft tissues, pain on extension, spasm contractures and adhesions.Mobilization is urgent to prevent contractures. Rotation is the most important exercise, and should be done with the upper arm supported in nearly horizontal extension to prevent the humeral head from impinging on the acromion. From this position the forearm, lifting or pulling down in a forward are against weights and pulleys, restores the rotatory power of the shoulder. 相似文献
75.
Rawitscher -Kunkel , Erika , and L. Machlis . (U. California, Berkeley.) The hormonal integration of sexual reproduction in Oedogonium. Amer. Jour. Bot. 49 (2) : 177–183. Illus. 1962.—Sexual reproduction in a heterothallic, nannandrous species of Oedogonium was investigated cytologically and physiologically. Several new observations are reported. Oogonial mother cells release a substance which attracts androspores to them. The androspores, when attached to the oogonial mother cells, grow in well-defined directions apparently in response to a hormone originating in the oogonial mother cells. An oogonial mother cell divides into an oogonium and a suffultory cell only after the attached androspores complete their development into dwarf males, each bearing an antheridium. Presumably the developing dwarf males provide a chemical stimulus for the division of the oogonial mother cell. During development, the oogonia become enveloped in a massive gel which also encases the antheridia cut off at the apical ends of the dwarf male plants. The gel appears to function as a sperm trap, preventing the dissemination of the sperm into the surrounding liquid. The sperm are attracted to the protoplasmic papilla which briefly protrudes through the oogonial pore indicating the operation of a second chemotactic agent. 相似文献
76.
Brian A. Blanksby Graeme A. Wood Leonard Freedman 《American journal of physical anthropology》1981,24(Z2):75-100
This paper discusses kinesiological aspects of human locomotion in terms of the incomplete morphological adaptation of the body to current lifestyles. Modern instrumentation used for biomechanical analyses is outlined for the most part in the context of human running. Investigations of spatiotemporal and segmental measures by electronic walkways, photography, optoelectronics and angle-angle diagrams are referred to, as is electromyography and direct force measurement. Three commonly identifiable areas of applied kinesiological research, namely sport, industry and medicine, are considered with reference to the prevention, treatment and after-care of injuries whether received on the sporting field, in the work place, or in an automobile accident. 相似文献
77.
A set of procedures is offered for assessing interraler reliability and certain aspects of validity of codes in cross-cultural studies. The method assumes that at least two independent raters have coded more than one trait. Each trait coded by one rater is correlated with each trait coded by a second, and all the codings by a single rater are intercorrelated with each other. The results are presented in a multitrait-multi-rater matrix. From this matrix it is possible to determine the interrater reliability and discriminant validity of trails in addition to a higher order concept based on pairs of traits. 相似文献
78.
N J Leonard 《Biopolymers》1985,24(1):9-28
An evaluation is made of the use of adenylate analogs as spatial, dimensional, and fluorescent probes of enzyme-coenzyme binding sites. 相似文献
79.
Structure and protein distribution for the capsid of Caulobacter crescentus bacteriophage phiCbK 总被引:3,自引:0,他引:3
Electron microscope images of negatively stained empty capsids of Caulobacter crescentus bacteriophage φCbK have been analyzed by computer Fourier methods. Two-dimensional computer density maps for the distribution of material in the capsid wall have been obtained by computer Fourier filtering which made possible the complete separation of contributions from the front and back of the capsid including overlapping Fourier coefficients. After scaling for the capsid thickness, using a one-dimensional reconstruction of data from edge-on views of the capsid wall and using topographical information provided by low-angle metal shadowing, a three-dimensional density distribution has been derived. A model for the distribution of subunits in the capsid is proposed which places each of the two major capsid subunit proteins (which are present in a 2:1 ratio) in quasi-equivalent bonding environments. A tentative model is presented in which assembly of the capsid (an elongated T = 7l icosadeltahedron) is regulated by the bonding geometry of the penton proteins. 相似文献
80.
The growth of rat pituitary tumor cells (GH1 line) maintained in monolayer culture was inhibited by dibutyryl cyclic AMP in a dose-related fashion. Neither PGE1 (2.8 × 10?5M) nor indomethacin (2.8 × 10?6M) had any significant effect on cell proliferation. Release of GH into the culture medium was stimulated by the cyclic AMP derivative but not by PGE1 or indomethacin. In short term experiments (15 min.) both in intact monolayers and in trypsin-treated cells incubated in suspension, PGE1 caused a 2–10 fold increase in cyclic AMP levels. This response, however, appeared to be of short duration reaching a maximum in 10 minutes. It is suggested that, at least in this line of pituitary tumor cells, PGE1 does not mimic the effect of cyclic AMP, for it probably cannot sustain the elevated intracellular levels of this nucleotide which seem to be necessary for growth inhibition and enhanced GH secretion. 相似文献