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71.
Flexible coaxial cables were modified to serve as microwave antennas operating at a frequency of 915 MHz. These antennas were inserted into nylon afterloading tubes that had been implanted in tumors using conventional interstitial implantation techniques for iridium-192 seed brachytherapy. The tumor volume was heated to 42-45 degrees C within 15 minutes and heating was continued for a total of 1 hour per treatment. Immediately following a conventional brachytherapy dose and removal of the iridium seeds the tumors were heated again in a second treatment. This interstitial technique for delivering local hyperthermia should be compatible with most brachytherapy methods. The technique has proved so far to be practical and without complications. Temperature distributions obtained in tissue phantoms and a patient are described.  相似文献   
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Plasma calcium and phosphate concentrations and alkaline phosphatase activities were examined retrospectively in 50 patients with histologically proven osteomalacia and 50 age- and sex-matched control subjects with normal bone histology. An abnormal plasma alkaline phosphatase activity was more useful than an abnormal plasma calcium or phosphate concentration in distinguishing between normal and osteomalacic subjects, producing a false-negative rate of 14% and a false-positive rate of 8%. False-negative and false-positive rates of 10% and 8% respectively were obtained when the presence of an abnormality in any one of the three biochemical measurements was used as a predictor of histological osteomalacia. When discriminant analysis was applied to plasma calcium, phosphate and alkaline phosphatase together a false-negative rate of 12% and a false-positive rate of 0% was obtained.  相似文献   
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Physiology of sucking in the normal term infant using real-time US   总被引:2,自引:0,他引:2  
Smith  WL; Erenberg  A; Nowak  A; Franken  EA  Jr 《Radiology》1985,156(2):379-381
Our study of 16 normal term, breast-fed infants documents real-time ultrasound as a technique for evaluating the oral portion of the sucking mechanism in infants. We also describe the mechanics of sucking used by the infants during breast-feeding.  相似文献   
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The prevalence of mitral valve pro.lapse in Chinese was determined by screening 156 heal- thy subjects and by patholobic examination of 86 adult autopsies. Mitral valve prolapse was found in 7.7% in the clinical study and 5.8% in the autopsy study. A slight female preponderance was noted.  相似文献   
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Homeostatic and psychologic alterations associated with infections and tumors are very interesting yet poorly understood pathophysiologic responses. Numerous anecdotal and indirect examples suggest that these responses occur through a link between the central nervous and immune systems (for review see Blalock, Bost, & Smith, 1985; Spector & Korneva, 1981; Maestroni & Pierpaoli, 1981; Felton et al., 1985; Jankovic, 1985). Interactions between the two systems are just now being described. One possible mechanism is direct modulation of the immune system by the sympathetic nervous system. This could occur in innervated immune organs such as spleen, thymus, and bone marrow (Felton et al., 1985). The evidence for this is that sympathectomy and lesioning of specific regions of the brain can be shown to both enhance and/or suppress immune responses (Miles et al., 1985; Roszman et al., 1985). Also, the firing rate of hypothalamic neurons is altered during an immune response (Besedovsky et al., 1977). Alternatively, hormonal involvement in immune reactions has been known for some time, in particular the immunosuppressive effects of glucocorticoids (for review see Cupps & Fauci, 1982). Recently, we and others found that neuroendocrine peptide hormones will modulate T and B lymphocytes plus other immunocyte responses (Besedovsky et al., 1977; Cupps & Fauci, 1982; Johnson et al., 1982; Wybran et al., 1979; Hazum, Chang & Cuatrecasas, 1979; O'Dorisio et al., 1981; Gilman et al., 1982; McCain et al., 1982; Mathews et al., 1983; Plotnikoff et al., 1985; Johnson et al., 1984). Furthermore, lymphocytes themselves can synthesize biologically active neuroendocrine hormones (Blalock & Smith, 1980; O'Dorisio et al., 1980; Smith & Blalock, 1981; Smith et al., 1983; Lolait et al., 1984; Ruff & Pert, 1984), as well as possess specific hormone receptors (Blalock et al., 1985; Johnson et al., 1982; Wybran et al., 1979; Hazum et al., 1979; O'Dorisio et al., 1981; Lopker et al., 1980; Payan, Brewster & Goetzl, 1984; Pert et al., 1985). Immune responses (Besedovsky, del Rey & Sorkin, 1981), thymic hormones (Healy et al., 1983), and lymphokines (Lotze et al., 1985; Woloski et al., 1985) have all been shown to exert hormonal effects. Thus, another method for communication between the immune and neuroendocrine systems seems to be through soluble factors such as neuroendocrine hormones. This review will concentrate on the latter topic, in particular on work this laboratory has done over the past few years to show the lymphocyte production and immunoregulatory actions of neuroendocrine hormones.  相似文献   
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