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751.
Studies and results on an ion beam produced at atmospheric pressure between a cathode point, a square diaphragm and a collector plane (anode) are presented. It is shown that the I(V) (characteristic at this device can become monotonous if a current feed back is applied to the diaphragm. Dimensions of beam impact are not affected by the electrostatical wind. The shape of the beam is given by calculation of electrostatical ion repulsion. This transducer allows gas flow measurement, this flow being a function of the current difference on the two half anodes. Theoretical calculations are in good agreement with the experiments. 相似文献
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A 43-year-old female alcoholic had massive hematobilia secondary to arterial trauma of a liver biopsy. The arterial bleeding site was successfully embolized through an angiographic catheter with Gelfoam sponge. No liver ischemia occurred and the patient has remained well. 相似文献
753.
Movement of the cervical spine in the sagittal plane was studied in ten normal subjects from 20 to 30 years of age without and with four different cervical orthoses: (1) polyethylene Camp plastic collar with chin and occiput piece, (2) plastizote Philadelphia collar, (3) four-poster and (4) SOMI (sternal occipital mandibular immobilization). The effect of the orthoses on restricting sagittal motion was measured simultaneously using roentgenographic and bubble goniometric methods. The subject was immobilized in a straight back chair to eliminate trunk motion, and lateral cervical spine films were taken of each subject in neutral, flexion and extension without and with each orthotic device. Distortion forces exerted on the orthotic devices were standardized by measurement of pressures at the chin and occiput. Roentgenographic measurements of flexion and extension and anteroposterior displacement of the cervical spine were compared to the measurements obtained by bubble goniometry. The four-poster and SOMI were found to be most effective in restricting extension and flexion respectively. The polyethylene and plastizote orthoses were significantly less effective in restricting motion. The bubble goniometer is an adequate clinical tool in assessing overall flexion-extension of the cervical spine but is not so precise and does not give information on the degree of motion at an individual vertebral level. 相似文献
754.
Dihydrodiols from anthracene and phenanthrene 总被引:2,自引:0,他引:2
DM Jerina H Selander H Yagi MC Wells JF Davey V Mahadevan DT Gibson 《Canadian Metallurgical Quarterly》1976,98(19):5988-5996
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Neighborhood mental health programs are challenged with the scientific and fiscal necessity of evaluating their services. Since most such programs are joint endeavors of neighborhood residents (usually a consumer board) and nonneighborhood professionals, such evaluative efforts require the sanction and collaboration of both groups to be maximally effective. However, the authors point out that collaboration is often strained by lack of trust and conflicts of interest. Study design may fail to consider neighborhood values, with the result that the provision of services is impeded, consumers are frightened or coerced, the role of paraprofessionals is threatened, and the consumer board's responsibilities to the neighborhood are ignored. The authors discuss those four issues and suggest ways of resolving them. 相似文献
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J Kachelhoffer J Dauchel A Pousse D Hohmatter JF Grenier 《Canadian Metallurgical Quarterly》1976,8(5):461-470
A simple device allowing a pulsatile flow to be obtained in isolated organ perfusion has been developed and applied to the vascular perfusion of isolated canine jejunal segments. The principle of the device consists of superimposing on a constant pressure produced by a roller pump, a pulsatile pressure of which the amplitude, frequency, and shape of the pulses can be adjusted separately and independently of the mean pressure value. The role of the arterial pulse in intestinal vascular perfusion has been studied by comparing the hemodynamic and metabolic behavior during alternate periods of pulsatile and nonpulsatile pumping. While no striking change in vascular resistance was observed, the O2 consumption was significantly increased under pulsatile flow. These results testify to better metabolic conditions and enhanced organ functions under pulsatile pumping and also argue for improved intestinal microcirculation despite the constancy of the vascular resistance. 相似文献
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