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Pulmonary angiograms and pulmonary lung perfusion scans on 162 patients with pulmonary embolism were comparatively analyzed. Among the expert angiographic panel members who independently evaluated the studies there was consistent agreement on the diagnosis, size of the emboli, and severity. Consistency of agreement among the expert pulmonary lung perfusion scan panelists was considerably less. These data demonstrate that, in addition to the lack of specificity of the lung perfusion scan for the diagnosis of pulmonary thromboemboli, there is a considerable problem of interpretation in this patient population. 相似文献
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Regional deposition of inhaled particles was studied experimentally in a hollow cast of the human larynx-tracheobronchial tree extending through the first six branching levels, and in twenty-six non-smoker human volunteers in vivo. Results of the hollow cast study indicated a linear dependence of particle deposition efficiency on the Stokes number for aerosols with aerodynamic diameters greater than 2 micrometers. Alveolar and total respiratory tract in vitro deposition in healthy non-smokers was minimal for particles of approximately 0.4 micrometers, and alveolar deposition for mouthpieces inhalations peaked for particles of approximately 3 micrometers. A new anatomic parameter, the bronchial deposition size (BDS), is introduced to permit the classification of various individuals and populations according to their tracheobronchial deposition efficiencies. The average BDS's were 1.20 cm for 26 healthy non-smokers, 1.02 cm for 46 cigarette smokers, 0.90 cm for 19 clinical patients being treated for obstructive lung disease and 0.60 cm for six severely disabled patients. 相似文献
67.
The in vitro inhibitory activity of rosamicin and erythromycin against 283 strains of nonfermenting, gram-negative bacilli was determined by using a broth dilution procedure. Rosamicin demonstrated greater activity than erythromycin against most strains tested. A number of species demonstrated significantly lower minimum inhibitory concentrations to rosamicin and would fall within the therapeutic range of the drug based on current pharmacological data. 相似文献
68.
TL Church 《Canadian Metallurgical Quarterly》1980,21(7):214-218
The objectives of beef feedlot preventive medicine are to reduce morbidity, mortality and culling rates, maximize feed efficiency and optimize expenditures for biologicals and pharmaceuticals. The veterinarian must provide regular inspection of all areas of the feedlot and constantly monitor disease incidence. The provision of advice on vaccination, treatment schedules, necropsies on all dead cattle and the regular analysis of disease and production records are all part of feedlot preventive medicine. All of this is aimed at improving net economical gain for the producer. 相似文献
69.
Lukasik J Bradley ML Scott TM Dea M Koo A Hsu WY Bartz JA Farrah SR 《Journal of food protection》2003,66(2):188-193
The efficacy levels of different physical and chemical washing treatments in the reduction of viral and bacterial pathogens from inoculated strawberries were evaluated. Escherichia coli O157:H7, Salmonella Montevideo, poliovirus 1, and the bacteriophages PRD1, phiX174, and MS2 were used as model and surrogate organisms. Chemicals readily available to producers and/or consumers were evaluated as antimicrobial additives for the production of washes. The gentle agitation of contaminated strawberries in water for 2 min led to reductions in microbial populations ranging from 41 to 79% and from 62 to 90% at water temperatures of 22 and 43 degrees C, respectively. Significant reductions (> 98%) in numbers of bacteria and viruses were obtained with sodium hypochlorite (50 to 300 ppm of free chlorine), Oxine or Carnebon (200 ppm of product generating "stabilized chlorine dioxide"), Tsunami (100 ppm of peroxyacetic acid), and Alcide (100 or 200 ppm of acidified sodium chlorite) washes. Overall, 200 ppm of acidified sodium chlorite produced the greatest reductions of microorganisms. Hydrogen peroxide (0.5%) was slightly less effective than free chlorine in a strawberry wash and caused slight fruit discoloration. Cetylpyridinium chloride (0.1%) was effective in the reduction of bacterial species, while trisodium phosphate (1%) was effective against viruses. The consumer-oriented produce wash Fit was very effective (> 99%) in reducing the numbers of bacteria but not in reducing the numbers of viruses. Another wash, Healthy Harvest, was significantly less effective than Fit in reducing bacterial pathogens but more effective for viruses. The performance of automatic dishwashing detergent was similar to that of Healthy Harvest and significantly better than that of liquid dishwashing detergent. Solutions containing table salt (2% NaCl) or vinegar (10%) reduced the numbers of bacteria by about 90%, whereas only the vinegar wash reduced the numbers of viruses significantly (ca. 95%). 相似文献
70.
Gergana I. Drandova Troy C. Messina Jae-Hyuk Choi Javier F. Hernandez John T. Markert 《Journal of Low Temperature Physics》2003,131(3-4):305-309
We report NMR lineshape, spin-lattice relaxation time T
1, and spin-spin relaxation time T
2 data at 17 MHz (8.07 T) for 89Y in the copper-oxide spin-chain compound Ca2+x
Y2–x
Cu5O10. For x=0, a broad, asymmetric line with width 90 kHz is observed for T=250–300 K. The spectra exhibit an appreciable average shift (H/H+0.7%) and sharpen at lower temperature, possibly due to increasing intrachain ferromagnetic correlations. T
1 and T
2 decrease with decreasing temperature. The Tl data imply a short correlation-time limit, with e=3–5×10–11 s. The T
2 data apparently include a contribution from dipolar interactions with copper nuclei. Relaxation time data for a doped (x=0.5) compound surprisingly show more rapid relaxation. 相似文献