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991.
Comparative bactericidal exposures for selected oral bacteria using carbon dioxide laser radiation 总被引:2,自引:0,他引:2
D N Dederich M A Pickard A S Vaughn J Tulip K L Zakariasen 《Lasers in surgery and medicine》1990,10(6):591-594
Although relatively high CO2 laser energies have been shown to sterilize root canals, the response of several bacterial strains to decreasing exposures of CO2 laser energy remains unknown. Freshly grown bacterial cells were irradiated on glass microscope coverslips. A comparison of equivalent energy exposures with differing parameters was made on the bacterial viability. No statistically significant difference was found in the energy required to kill closely related bacterial species. However, the energy density required to kill greater than 99.5% of the bacteria is less than 200 J/cm2, much less than that shown to sterilize in a previous study. 相似文献
992.
E M Sacks L L Fajardo B J Hillman G W Drach J A Gaines H R Claypool N J Clinger D J Fillmore K R Hunt G D Pond 《The Journal of urology》1990,144(6):1341-1346
Most publications citing the effectiveness of renal extracorporeal shock wave lithotripsy have used plain abdominal radiography to assess residual calculi after treatment. We compared radiologist sensitivity and specificity in the detection of calculi on plain abdominal radiographs versus conventional film-screen and digital renal tomograms in extracorporeal shock wave lithotripsy patients. Of the patients 50 were imaged before and within 24 hours after lithotripsy. Six radiologists evaluated the resultant 300 studies for the presence and location of calculi. The mean sensitivity for digital tomograms was 83% for pre-lithotripsy and post-lithotripsy studies, which was significantly higher than for plain abdominal radiography and conventional tomography after lithotripsy. However, there were significantly more false positive stone diagnoses associated with digital tomogram interpretation. Signal detection analysis verified the over-all superiority of digital tomography for post-extracorporeal shock wave lithotripsy imaging. Calculus detection by conventional and digital tomography is superior to detection by plain abdominal radiography. However, because we did not perform delayed imaging, it is not possible to say what impact digital tomography might have on the management of extracorporeal shock wave lithotripsy patients. 相似文献
993.
994.
As the result of immunological examination of 21 children with developmental defects of the chest and analysis of the course of the postoperative period in 136 children, among which 36 had hereditary syndromes of systemic connective-tissue dyshistogenesis, it was found that suppurative complications of thoracoplasty, which are encountered in 15% of children with isolated developmental chest defects and in 33.3% of those with the above mentioned syndromes, were caused to a great measure by disorders of the immune status. The most serious immunological deviations were encountered in the Marfan syndrome due to impaired phagocytic activity of neutrophils and monocytes, decreased number of T, T active, and B lymphocytes, and diminished function of T helpers. In unclassified complexes of developmental defects with Marfaneic ++ phenotypes, the immunological disorders were similar, but less deep. In the Ehlers-Danlos syndrome, a decrease of the number of immunocompetent cells, function of T helpers, and neutrophils was mainly revealed. In isolated forms of funnel chest the function of monocytes and the number of immunoglobulins are mainly decreased. 相似文献
995.
996.
997.
Patients with uremia have excess levels of parathyroid hormone (PTH). It has been reported that excess PTH is associated with bone marrow fibrosis. The present study was undertaken to examine the in vitro effect of intact 1-34 PTH and the active 1-34 N-terminal fragment on human bone-marrow-derived fibroblasts. Proliferation of fibroblasts was not stimulated by PTH in concentrations present in uremia (5-30 U/ml) nor by uremic sera which contained either high or low PTH levels. The lack of stimulation contrasted with the activity of both PTH preparations in other systems, i.e., inhibitory to erythroid colonies and stimulatory to heart muscle cells. 相似文献
998.
A V Ovechkina V I Sadof'eva T N Shumskaia M I Iakovleva 《Ortopediia travmatologiia i protezirovanie》1990,(8):31-36
203 patients with juvenile kyphosis, aged 11-16 years, have been subjected to the complex examination, including ++clinico-roentgenologic and physiologic methods. Along with the cardinal signs, common for juvenile kyphosis diagnosis and characteristic of the dystrophic process (wedge distortion, osteoporosis of vertebra bodies and fragmentation of their apophyses, dedifferentiation of the bone structure, height reduction and pathologic restructuring of intervertebral disks following the pattern of fibrosis, presence of discal hernia), the signs of bone ++ dysplasia of spine and skeleton in general should be singled out of the roentgenologic characteristic of disease which determine the variants of pathologic process course and treatment tactics. The presence of dysontogenesis signs in patients with juvenile kyphosis is suggested. 相似文献
999.
A I Kaz'min A M Gerasimov A Iu Toporov S M Toporova L N Furtseva 《Ortopediia travmatologiia i protezirovanie》1990,(3):42-45
Pronounced changes in the content of collagen, non-collagen proteins and the activity of a number of lysosomic enzymes have been established in the bone tissue of the vertebral bodies obtained on diskepiphysectomy in the patients with dysplastic scoliosis. Numerous correlation links between the metabolic parameters and the spinal deformation a year after diskepiphysectomy have been determined. 相似文献
1000.