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The application of phenological data together with meteorological and pollen data in a comprehensive analysis gives an opportunity to draw conclusions on variability of the starting date of the pollen season and its dynamics in terms of meteorological factors. It is quite important especially due to the fact that studies conducted all over Europe have proved that species phenology responds to climate warming trends. There has been observed a tendency to an earlier onset of spring flowering and leafing as well as the lengthening of the growing season. Although phenological network studies differ with regard to regions, species, events observed and applied methods, their data show a clear temperature-driven extension of the growing season by up to 2 weeks in the second half of the 20th century in mid- and high northern latitudes; for example, in Germany changes in timing of phenological spring events have been estimated at about -1.6 days / decade, while in Switzerland: -2.3 days / decade. Despite interannual variability in flowering date, caused by specific meteorological conditions each year, long-time series of phenological data from the area of Poland have proved that hazel flowering occurred in the surroundings of Warsaw later in the 50’s (third decade of March) than it is observed at the beginning of the 21st century (second decade of March). There is a lack of such long time series of pollen data, but we can suspect that the hazel pollen season has changed similarly to the time pattern of its flowering. Plants are very sensitive to weather conditions, therefore it is important to know as precisely as possible the impact of meteorological conditions on a plant’s reactions. The determination of thermal thresholds for a specific plant’s reactions may be beneficial for this purpose. The estimated value of Positive Degree Days (PDD> 50), which caused the first Corylus flowers (F2 phenophase) to bloom in the study years, requires testing in future years to make the threshold values credible.
The course of Alnus spp. pollen seasons was compared in two cities, Lublin and Warsaw, located at a small distance from each other but included in different climatic regions of Poland. The studies were conducted using the volumetric method. It was shown that Alnus pollen seasons started in Warsaw earlier and were much shorter than in Lublin. The span between the start dates of pollen seasons was similar and it was 53-54 days. Peak days occurred in both cities most often in the second decade of March, but in Warsaw they were recorded several days earlier. Maximum concentrations reached higher values in Lublin, whereas annual totals were higher in Warsaw. The number of days with the concentration > 50 pollen grains × m⁻³ per 24 hours was 5-27 days for Warsaw and 10-19 days for Lublin over 7 years of study.
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Nasal provocative test (NPT) can be defined as a method for recreating upper respiratory tract response to natural allergens or irritants. It can be used in solving nasal patophisiology problems: establishing whether and how the patient's nose is sensitive to antigens or irritants; quantitative evaluation of sensitivity; establishing factors influencing sensitivity. This method is employed to confirm clinical diagnosis in cases where difficulties arise in interpretation of diagnostic tests. The study based on nasal provocative tests establish an allergy to pollen in cases of pollinosis, and select appropriate components for the desensitising vaccine. Sample group included 53 patients, 29 were females and 24 were males, aged 15-42 years, selected from 1,021 patients diagnosed between 1999-2002 in the Allergology Department of the ENT Department of the MMI. The sample patients were diagnosed based on additional tests with allergic inflammation of the nasal mucosa caused by allergy to pollen of such plants as birch, grass, rye, mugwort and plantain. Research methods included: subjective physical examination, prick tests, total and specific IgE levels in serum, nasal provocative tests and rhinomanometric examination. Allergen solution was administered onto the mucosa with a calibrated atomiser. NPT solutions containing pollen of birch, grass, rye, mugwort and plantain were used. Provocative test was considered positive if, following allergen provocation, rhinomanometric examination revealed an increase in respiratory resistance by at least 40% in comparison with the control test. On the basis of the study, 2 conclusions were drawn: 1) Nasal provocative test is an essential element in diagnostics of allergic nasal obstruction. 2) Rhinomanometry, as an objective method of examining nasal patency, is crucial for evaluating the nasal provocative test.
In allergology practice and research, it would be convenient to receive pollen identification and monitoring results in much shorter time than it comes from human identification. Image based analysis is one of the approaches to an automated identification scheme for pollen grain and pattern recognition on such images is widely used as a powerful tool. The goal of such attempt is to provide accurate, fast recognition and classification and counting of pollen grains by computer system for monitoring. The isolated pollen grain are objects extracted from microscopic image by CCD camera and PC computer under proper conditions for further analysis. The algorithms are based on the knowledge from feature vector analysis of estimated parameters calculated from grain characteristics, including morphological features, surface features and other applicable estimated characteristics. Segmentation algorithms specially tailored to pollen object characteristics provide exact descriptions of pollen characteristics (border and internal features) already used by human expert. The specific characteristics and its measures are statistically estimated for each object. Some low level statistics for estimated local and global measures of the features establish the feature space. Some special care should be paid on choosing these feature and on constructing the feature space to optimize the number of subspaces for higher recognition rates in low-level classification for type differentiation of pollen grains. The results of estimated parameters of feature vector in low dimension space for some typical pollen types are presented, as well as some effective and fast recognition results of performed experiments for different pollens. The findings show the ewidence of using proper chosen estimators of central and invariant moments (M21, NM2, NM3, NM8 NM9), of tailored characteristics for good enough classification measures (efficiency > 95%), even for low dimensional classifiers (>3) for type differentiation of pollens grain.
The aim of the study was to investigate the correlation between the level of reactivity in conjunctival provocation test and conjunctival symptoms that develop during the pollination season in grass allergic patients. Conjunctival provocation test with grass pollen allergens was performed in 22 patients suffering from pollinosis. During grass pollination season all patients monitored their symptoms with Symptoms Score Cards. A parallel measurement of the level of grass pollen count was carried out on a daily basis by volumetric method. The mean grass pollen count which triggered the reaction in individual patients depended on the results of conjunctival provocation test. The lowest pollen count level was observed in cases of patients with positive conjunctival provocation test at low allergen extract concentration of 160 and 500 BU/ml, whereas the highest count in cases of 1,600 BU/ml. The difference between the results was found to be statistically significant. A threshold grass pollen concentration for conjunctival symptoms was established at the level of 22 grains/m3. We conclude that the patients with pollinosis and high reactivity in conjunctival provocation test develop conjunctival symptoms earlier during grass pollination season than the patients who are characterised by lower reactivity during conjunctival provocation test.
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