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21.
Stereometry in very close-range stereophotogrammetry with non-metric cameras for human movement analysis 总被引:1,自引:0,他引:1
In this paper a stereophotogrammetric algorithm based on a black-box approach to the modelling of object to image spaces relationship is proposed. The algorithm is well suited for 'very close-range photogrammetry', with respect to experiments in which the measurement field is 0.5 X 0.5 X 0.5 m or smaller, as in the analysis of a few or small body segments movements. The attainable accuracy is high, better than 0.1% of the observation distance. Non-professional and even different cameras can be used. Consequently an inexpensive experimental set-up can be realized. A very simple, cheap and easily usable calibration object is needed. Computation time for the reconstruction of object-space co-ordinates of point body landmarks is one order of magnitude lower than in the case of the Direct Linear Transformation (DLT) (Abdel Aziz and Karara, Proceedings of the ASP/U1 Symposium on Close-Range Photogrammetry, pp. 1-18. American Society of Photogrammetry, 1971; Marzan and Karara, Proceedings of the Symposium on close-range Photogrammetric Systems, pp. 420-467. American Society of Photogrammetry, 1975). Computation time for calibration is two-fold in respect of the DLT. An example of application to the recording of the movements of the index finger with respect to the metacarpophalangeal joint is given. 相似文献
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23.
James C. Lacey Jr. Leo M. Hall Dail W. Mullins Jr. 《Origins of life and evolution of the biosphere》1985,16(1):69-79
The genetic code appears to be a logic matrix in which, generally speaking, there is a correlation between the hydrophobicities of amino acids and their anticodonic nucleotides. There are several exceptions to this generality, however, and using previous data on hydrophobicity and binding constants, coupled with new data on reaction rates, we rationalize several of the anticodonic assignments. 相似文献
24.
Salt gradient elution of crude histoplasmin on CM-Sepharose CL6B at pH 3.0 was used in essentially a one-step procedure to isolate the h, m, and non-m antigens ofHistoplasma capsulatum and free them of any c antigen common to other pathogenic fungi. The h antigen fraction was pure; the isolated m and non-m antigens contained less than 0.1% of the c antigen present in the original preparation. The residual c antigen in these fractions was removed by affinity chromatography on Affigel-10 coupled to aBlastomyces dermatitidis fungal antiserum. The final preparations of h, m, and non-m were pure when tested by immunodiffusion (ID), sodium-dodecyl-sulfate-polyacrylamide-gel electrophoresis (SDS-PAGE), or electrofocusing. The antigens were serologically stable at neutral pH for at least three months at 10°C. The relative molecular weights, isoelectric points, and amino acid composition of the antigens are described. 相似文献
25.
The cDNA sequence for the protein-tyrosine kinase substrate p36 (calpactin I heavy chain) reveals a multidomain protein with internal repeats 总被引:41,自引:0,他引:41
We have isolated and sequenced a full-length cDNA clone for the protein-tyrosine kinase substrate p36 (calpactin I heavy chain). This sequence predicts a 339 amino acid (Mr 38,493) protein containing an N-terminal region of 20 amino acids, known to interact with a 10 kd protein (light chain), and a C-terminal region, found to contain two Ca2+/phospholipid-binding sites, that can be aligned as four 70 amino acid repeats. A single p36 gene was detected in the mouse genome, and a major p36 mRNA of 1.6 kb was found to be expressed in different mouse tissues. Unexpectedly, p36 and the phospholipase A2 inhibitor lipocortin I were found to be 50% identical in sequence over the C-terminal 300 residues. The function of p36 and its relation to other proteins are discussed. 相似文献
26.
Stimulation of Phospholipase A2 and Secretion of Catecholamines from Brain Synaptosomes by Potassium and A23187 总被引:3,自引:3,他引:0
Abstract: Potassium depolarization of rat brain synaptosomes (containing incorporated l-acyl-2-[14C]arachidonyl-phosphatidylcholine) stimulated endogenous phospholipase A1 (EC 3.1.1.32) and A2 (EC 3.1.1.4), as determined by the formation of [14C]lysophosphatidylcholine, [14C]arachidonate, and [14C]prostaglandins, and also stimulated the secretion of [3H]catecholamines. The phospholipase A2 stimulation, dependent on calcium, was elicited in resting synaptosomes by A23187 and was demonstrated with incorporated 1-acyl-2-[l4C]oleoyl-phosphatidylcholine but not with incorporated [I4C]phosphatidylethanolamine or [l4C]phosphatidylserine. Inhibitors of phospholipase A2 [p-bromophenacylbromide (10 μM), trifluoperazine (3 μM), and quinacrine (3 μM) reduced the potassium-stimulated [3H]catecholamine release from synaptosomes to 78, 39. and 55%, respectively, of depolarized controls. The addition of lysophosphatidylcholine increased the release of [3H]norepinephrine to levels observed with potassium depolarization, whereas lysophosphatidylethanolamine, lysophosphatidylserine, and sodium dodecyl sulfate were much less effective. Potassium stimulation of synaptosomes increased the endogenous levels of free arachidonic acid and prostaglandins E2 and F2α. Indomethacin and aspirin decreased the amounts of prostaglandins formed, allowed the accumulation of free arachidonic acid, and diminished the potassium-stimulated release of [3H]dopamine. p-Bromophenacylbromide inhibited the formation of prostaglandin F2α. Addition of prostaglandin E2 inhibited, whereas prostaglandin F2α enhanced the release of [3H]norepinephrine. These results suggest that calcium influx induced by synaptosomal depolarization activates endogenous phospholipase A2, with subsequent formation of lysophosphatidylcholine and prostaglandins, both of which may modulate neurosecretion. 相似文献
27.
Microorganisms of the San Francisco Sour Dough Bread Process: I. Yeasts Responsible for the Leavening Action 总被引:6,自引:5,他引:1 下载免费PDF全文
Two hundred isolates from San Francisco sour dough French bread fermentations (40 from each of five different bakeries) were screened by fermentation tests and for their ability to grow in the presence of cycloheximide (Actidione). All of the isolates from four of the bakeries and 70% of those from the fifth were unable to utilize maltose but grew well on other sugars, even in the presence of cycloheximide. The remaining few isolates from the fifth bakery utilized maltose but not galactose and were inhibited by cycloheximide. No bakers' yeast types were found. Sixteen of the maltose-negative and five of the galactose-negative isolates were subjected to more rigorous taxonomic procedures. All of the maltose-negative isolates were identified as asporogenous strains of Saccharomyces exiguus (Torulopsis holmii) and the galactose-negative ones, as S. inusitatus. The predominance of S. exiguus, its vigor in the particular acidic environment of the sour dough, and the correlation of its numbers with the leavening function constitute strong evidence on the role of this organism in the sour dough system. 相似文献
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29.
Prophylactic Effects of γ-Aminobutyrylhistidine (Homocarnosine) on Experimental Staphylococcal Infections in Mice 下载免费PDF全文
Prophylactic administration of the dipeptide homocarnosine induced a high degree of resistance to staphylococcal infections in Swiss albino mice. It expressed its antistaphylococcal properties 1 hr after administration, and this protection lasted for at least 1 month. Although 5 mg per animal (approximately 200 to 250 mg/kg) was routinely used in our studies, experiments showed that comparable results could be obtained with 1.5 mg per animal. Rechallenge experiments indicated that an active infection by itself may confer immunity up to 4 weeks, but an infection after treatment with homocarnosine gave complete immunity to reinfection for at least 2 months. Studies in vitro showed that homocarnosine had no effect on the growth or certain other characteristics (ability to ferment mannitol, liquefy gelatin, and to produce coagulase, deoxyribonuclease, and pigment) of S. aureus. It appears that resistance induced by this peptide is an indirect effect mediated by some nonimmunological host reaction. The possible involvement of homocarnosine, among other compounds, in the protective action of deproteinized beef extract against staphylococcal infections is suggested. 相似文献
30.
Effects of a Single Histoplasmin Skin Test on the Serological Diagnosis of Histoplasmosis 总被引:6,自引:0,他引:6 下载免费PDF全文
Leo Kaufman Robert T. Terry Joseph H. Schubert David McLaughlin 《Journal of bacteriology》1967,94(4):798-803
Numerous reports have indicated that a single histoplasmin skin test may stimulate humoral antibodies to Histoplasma capsulatum antigens in histoplasmin-hypersensitive individuals. Although these investigations concur that antibody elevations are evoked, they vary in the reported degree of incidence and response induced, and they cast doubt on the interpretation of serological tests in the diagnosis of histoplasmosis. Histoplasmin-hypersensitive subjects (114) were bled prior to administration of the skin test, 2 days later, at the time this test was read, and 15 and 30 days after testing. No significant antibody titers were observed at 2 days. At 15- and 30-day intervals, only 17 (15%) of the subjects demonstrated circulating antibodies. All 17 showed agar gel bands; 5 demonstrated no complement-fixation (CF) titers, 10 produced CF antibodies ranging from 1:8 to 1:16, and 2 demonstrated titers of 1:32. The data suggest that skin testing does not interfere significantly with antibody levels in sera drawn approximately 2 days after administration of antigen. However, since titers as high as 1:32 were obtained at later intervals, such reactions should be evaluated cautiously and only after consideration of clinical findings. 相似文献