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Journal of Chemical Ecology - Entomopathogenic fungi (EPF) can be experimentally established in several plant species as endophytes. Ecological effects of EPF inoculations on plant growth and...  相似文献   
2.
A Newton-type method is used to solve the target motion analysis (TMA) problem with respect to bearing and frequency measurements from a passive sonar system. In many long-range sonar situations the TMA problem is ill conditioned and suffers from a small signal-to-noise ratio. Although Kalman filters have been investigated extensively it is known that maximum likelihood (ML) estimation is superior in these cases. The main reason for the good performance of the ML method is that the underlying numerical optimization problem deals with the ill conditioning of the problem. This work illustrates how the conditioning depends on the geometry of the tracks and the signal-to-noise ratio. Monte Carlo simulations with respect to the measurement noise show the influence on the ML estimation performance for three specific cases concerning multileg situations and bottom bounce measurements  相似文献   
3.
To evaluate the diagnostic value of serum cytokine levels and cytokine receptor levels in the diagnosis of acute rejection after heart transplantation, we measured soluble CD8 and soluble CD25 in the serum of heart transplant recipients. The results were compared with endomyocardial biopsy (EMB) histopathology, lymphocyte activation by morphologic inspection of peripheral blood cells (cytoimmunologic monitoring), clinically manifested infections, and the maintenance immunosuppressive therapy. Significantly increased levels were observed in cases of lymphocyte activation in cytoimmunologic monitoring indicative of either rejection or infection. In clinically documented cytomegalovirus (CMV), bacterial, and Pneumocystis carinii infections, increased levels of soluble CD25 were observed. Soluble CD8 was only increased in a single case of P. carinii infection. A statistically significant correlation was calculated between the levels of soluble CD8 and whole blood cyclosporin A level. Considering chemotherapy, the levels of soluble CD8 showed an inverse correlation with the daily dosage of azathioprine. In conclusion, the levels of soluble CD8 and CD25 are associated with lymphocyte activation in peripheral blood, but do not differentiate between lymphocyte activation indicative of rejection or infection. No relationship was observed between levels of soluble CD8 and CD25, and EMB histopathology. Therefore, the assessment of these two cell products has no diagnostic potential for monitoring acute rejection after heart transplantation.  相似文献   
4.
In order to achieve esthetically more satisfying results, it has been proposed to place ITI implants with their border between the rough and smooth surfaces below the level of the alveolar crest, thereby obtaining a submucosally located implant shoulder following healing. The aim of the present experimental study was to clinically and radiographically evaluate the tissue response to the placement of one-stage transmucosal implants with the border between the rough and the smooth surfaces sunk by 1 mm into a subcrestal location. 11 patients underwent comprehensive dental care including the placement of 2 implants of the ITI Dental Implant System in the same quadrant (test and control). Randomly assigned control implants were placed according to the manufacturer's instructions, i.e. the border between the rough titanium plasma-sprayed and the smooth polished surfaces precisely at the alveolar crest. At the test implant the apical border of the polished surface was placed approximately 1 mm below the alveolar crest. Probing bone levels were assessed at implant placement (baseline), 4 and 12 months later. Modified plaque and modified gingival indices were recorded at 1, 2, 3, 4 and 12 months. Clinical probing depth and "attachment" levels were measured at 4 and 12 months. All parameters were assessed at 6 sites around each implant. The mean for each implant was calculated and used for analysis. The Wilcoxon matched pairs signed rank test and the Student t-test were applied to detect differences over time and between the test and control implants. At baseline, a mean difference in probing bone level of -0.86 mm (SD 0.43 mm, p < 0.05) was found between test and control implants with the test implants being placed more deeply. Both test and control implants lost a significant amount of clinical bone height during the first 4 months (test 1.16 mm, p < 0.05; control 0.58 mm, p < 0.05). However, only the test implants significantly lost clinical bone height from 4-12 months (test 1.04 mm, p < 0.05; control 0.45 mm, p = 0.08). Overall, the test implants lost 2.26 mm and the control implants 1.02 mm of bone height during the first year of service. On the average, the test implants demonstrated a bone level of 0.38 mm lower than the controls at 12 months. Except for the modified gingival index at 4 months (mean difference 0.21, SD 0.19, p < 0.05), no clinical parameters yielded significant differences between test and control implants at any time. It is concluded that in addition to the crestal bone resorption occurring at implants placed under standard conditions, the bone adjacent to the polished surface of more deeply placed ITI implants is also lost over time. From a biological point of view, the placement of the border between the rough and the smooth surfaces into a subcrestal location should not be recommended.  相似文献   
5.
The routine use of rapid methods of detecting yeasts in brewing control laboratories is discussed. A modified microcolony procedure exploiting epifluorescence is used to monitor packaging of sterile beer. Saccharomyces diastaticus, which is a potentially serious contaminant during aseptic bottling of lager can be recovered selectively by incubation at 37°C. Neither method is specific for a single species and further rapid identification can be carried out using the API carbohydrate diagnostic system.  相似文献   
6.
This study describes the establishment and first results of a continuous surveillance system of antimicrobial resistance among bacteria isolated from pigs, cattle and broilers in Denmark. The three categories of bacteria tested were: 1) indicator bacteria (Escherichia coli, Enterococcus faecalis, Enterococcus faecium), 2) zoonotic bacteria (Campylobacter coli/jejuni, Salmonella enterica, Yersinia enterocolitica), and 3) animal pathogens (E. coli, Staphylococcus aureus, coagulase-negative staphylococci (CNS), Staphylococcus hyicus, Actinobacillus pleuropneumoniae). A total of 3304 bacterial isolates collected from October 1995 through December 1996 were tested for susceptibility to all major classes of antimicrobial agents used for therapy in Denmark. Bacterial species intrinsically resistant to an antimicrobial were not tested towards that antimicrobial. Acquired resistance to all antimicrobials was found. The occurrence of resistance varied by animal origin and bacterial species. In general, resistance was observed more frequently among isolates from pigs than from cattle and broilers. The association between the occurrence of resistance and the consumption of the antimicrobial is discussed, as is the occurrence of resistance in other countries. The results of this study show the present level of resistance to antimicrobial agents among a number of bacterial species isolated from food animals in Denmark. Thus, the baseline for comparison with future prospective studies has been established, enabling the determination of trends over time.  相似文献   
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