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61.
In a previous study we have demonstrated that endogenous neurotrophin 3 (NT3) is required for the survival of most sympathetic neurones in postnatal rats. However, the mechanisms underlying the action of NT3 on sympathetic neurones is not known. Neither is it understood whether NT3 is retrogradely transported from peripheral tissues or acts locally in an autocrine fashion. In the present study, NT3-mRNA was quantified in sympathetic effector tissues and NT3 protein was localized in intact and lesioned sympathetic nerves in rats. NT3-mRNA is expressed and developmentally regulated in many effector tissues including mesenteric arteries, salivary gland, heart and kidney but hardly detectable in the superior cervical ganglia of adult animals. The majority of sympathetic neurones express immunoreactivity for TrkA and TrkC in both neonatal and adult rats. Sympathetic somata are normally immunoreactive for NT3, but the immunoreactivity is abolished by systemic administration of NT3 antibodies or axotomy of postganglionic neurones, suggesting an accumulation of NT3 from extraneuronal sources. Furthermore, the detection of NT3-immunoreactivity in the internal carotid nerve as early as 3 h following a compression and only on the distal side indicates endogenous NT3 is retrogradely transported by sympathetic neurones. These studies provide evidence indicating that NT3, like nerve growth factor, is an effector tissue-derived neurotrophic factor for sympathetic neurones both during development and in the adult animal. Thus, we have provided a clear example that one type of neurone derives, through a retrograde transport mechanism, two neurotrophic factors simultaneously from its peripheral effector tissues. 相似文献
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MA Gamba M Martinelli HJ Schaad RA Streuli J DiPersio L Matter HB Ris F Marchal EL Kaplan DL Stevens R Malinverni 《Canadian Metallurgical Quarterly》1997,24(6):1118-1121
Invasive group A streptococcus (GAS) infections are emerging diseases; however, person-to-person transmission of invasive GAS producing life-threatening infection has been observed rarely. We report a small intrafamilial cluster of life-threatening GAS infections. A previously healthy 47-year-old father developed necrotizing fasciitis of the neck. Two days later, his 16-year-old daughter developed streptococcal angina, pneumonia, and pleural empyema. Both patients had signs of streptococcal toxic shock syndrome. Pulsed field gel electrophoresis revealed that the M6 strains of GAS isolated from the father and daughter had identical patterns. Cases of person-to-person transmission of invasive GAS infection reported in the literature are also reviewed. 相似文献
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RA Sutherland CC Wright LMJ Verstraeten DJ Greenwood 《Nutrient Cycling in Agroecosystems》1986,10(3):251-262
Much effort is devoted to testing N-fertiliser models against measurements of yield in N-fertiliser experiments. We show that the economic optimum application of N-fertiliser can often only be determined very imprecisely from such measurements, even when they are accurate. Hence any attempt to evaluate a simulation model by comparing simulated with experimentally determined optima, or to relate these experimental optima to other factors thought to influence yield, will be uninformative. Big differences between simulated and measured optima will occur even with good models, which may explain the apparent poor performance of some simulation models in the literature.We suggest, instead, the systematic inspection of the differences between simulated and observed yields at the levels of N-fertiliser applied in an experiment. A study of the relationship of these differences to the applied level of N-fertiliser and to other factors of interest will be a more informative method of evaluating a model, and of suggesting other factors for inclusion in it. An example of the use of the method is given. 相似文献
64.
Dipl. Wirt.-Inform. Ralf Knackstedt Christian Brelage RA Master of Arts Noogie C. Kaufmann 《WIRTSCHAFTSINFORMATIK》2006,48(1):27-35
A broad variety of juridical requirements has to be considered during the development of Web-applications. Disregard of these requirements holds severe financial dangers. A complete compilation of juridical requirements is complicated due to the multitude of juridical areas and the variety of Web-applications. Therefore, a development-driven juridical framework is suggested. From a software engineering point of view it is crucial to capture requirements at an early stage of development in order to avoid much higher costs at a later time. Thus, specialized conceptual modelling methods are examined with regard to their capability to model juridical requirements. A lack of methodical support is identified which is addressed by a systematic adaption and extension of the eW3DT method. 相似文献
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NR Powe RI Griffiths AJ Watson GF Anderson G de Lissovoy JW Greer RJ Herbert RA Milam PK Whelton 《Canadian Metallurgical Quarterly》1994,4(7):1455-1465
To examine the effects of recombinant human erythropoietin (rHuEPO) on hospital utilization, hospital costs, and Medicare reimbursements for hospital care, a longitudinal, matched cohort study was conducted using Medicare claims data of 23,806 Medicare-eligible, dialysis patients who received rHuEPO, did not have a transplant, and were alive for 18 mo or longer and 22,720 controls matched on age, sex, race, cause of ESRD, and dialysis modality. The relative odds (rHuEPO versus control) of admission for all causes and for specific causes over 9 mo, adjusted for admission in the prior 9 mo and the per patient change in total admissions, inpatient days, hospital costs, and Medicare hospital payments between the prior 9-mo period and the subsequent 9-mo period was examined. The adjusted relative odds (95% confidence interval) of admission (rHuEPO versus control) was: higher and statistically significant for all causes, 1.08 (1.03 to 1.14); seizure, 1.52 (1.28 to 1.75); vascular access revision, 1.11 (1.06 to 1.17), and heart failure, 1.17 (1.09 to 1.26); higher but not statistically significant for angina, 1.09 (0.99 to 1.20) and stroke, 1.08 (0.86 to 1.31); and lower but not statistically significant for myocardial infarction, 0.91 (0.72 to 1.10); peripheral vascular disease, 0.81 (0.60 to 1.02); anemia, 0.86 (0.56 to 1.17); and depression, 0.89 (0.37 to 1.40). The mean change per 1,000 patients in admissions was less by 38 (P = 0.03) because of fewer readmissions, and in days was 1,309 less (P < 0.001), for patients treated with rHuEPO versus controls. The mean change per patient in hospital costs was $371 less and was statistically significant (P = 0.03) and in Medicare hospital payments was $132 less but was not statistically significant (P = 0.43) for patients treated with rHuEPO versus controls. rHuEPO was associated with an increase in the probability of hospital admission (particularly admissions potentially related to adverse effects) but a decrease in readmissions, overall admissions, hospital days, and cost to hospitals in this cohort of patients surviving for 18 mo. Although not realized short term, Medicare savings from potential rHuEPO-related reductions in hospital care may be long term through future adjustments in diagnosis-related group-based hospital payment. 相似文献
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Five non-smoking patients were diagnosed as having allergic bronchopulmonary aspergillosis in 1978/9. All have been treated since then with inhaled corticosteroids, using short courses of self-administered oral corticosteroids for symptomatic exacerbations. Over a mean 15 years of follow-up, they have required on average less than one course of oral drugs per annum. Regular monitoring of spirometry has shown no evidence of deterioration, and all have close to normal gas transfer. All have some localized bronchiectasis on CT scanning, in two cases probably occurring after treatment started, but in no case is there any respiratory disability. We conclude that this is a safe and effective method for the management of allergic bronchopulmonary aspergillosis when diagnosed before persistent hyphal colonization of the airways has occurred. 相似文献