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1.
V. D. Savitsky  V. N. Kobzar 《Grana》2013,52(5):314-318
Aerobiological investigations of the last ten years in the former USSR emphasised, preferentially the following problems: content of pollen in the air, pollen transport, and impact of pollen on the health of the human. Pollen grains which cause various allergic diseases have been the main object of extensive aerobiological studies. Ado and his collaborators have made valuable contributions to Aerobiology in the former USSR (Ado 1978, 1980, 1989, 1990; Ado & Gubankova, 1979 a, b). Their investigations confirmed the existence of a correlation between the number of allergic patients and the concentration of pollen grains in the atmosphere, and some peculiarities of the allergic diseases prevalent in towns.

Later, aerobiology was elaborated by the investigations of Kobzar (1987), Kobzar & Kharitonova (1990), Kobzar et al. (1990, 1991), etc. The possibility of airborne pollen grains as indicators of environmental contamination and pollution levels was demonstrated. Various data show the periods during which pollen grains are present in atmosphere, their peaks and the levels of concentration which are able to cause allergies in the territory of the former USSR.  相似文献   

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The aim of this work is to present the atmospheric pollen concentrations of Palencia, Spain. Data were collected for three consecutive years (1990–92). An active volumetric pollen trap, type CAP2, was used. During this time, 88 different pollen types were identified, of which 27 occured at more than 0.15% of the total pollen recorded annually. These types formed the main pollen spectrum of this sampling station. Pollen coming from herbs (Poaceae, Chenopodiaceae, Plantago Urticaceae, etc.) was predominant (53.79%); arboreal pollen (Quercus, Populus Cupressaceae, etc.) represented 42.11%, and pollen from shrubs (Ericaceae, Sambucus etc.) only 4.10%.

May and June was the time of the year with maximum pollen emission to the air. This was due to the quantities of pollen coming from Poaceae and Quercus which together represent 47.25% of the pollen recorded over the three‐year sampling period. Herbaceous pollen appeared throughout the year with maximum concentrations recorded in the spring, coinciding with the maximum levels of arboreal pollen in the atmosphere.

An analysis of multiple regression and one‐way anova test between pollen concentrations and selected meteorological parameters show that relative humidity and average temperature are the meteorological factors most correlated with the concentrations of specific pollen types (Plantago, Ligustrum, Sambucus, Carex). In the same way, when the winds are predominantly from the northeast (second quadrant), there are higher pollen concentrations of Sambucus Ericaceae and Mercurialis.  相似文献   

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Annual observations of seabirds within Prydz Bay, East Antarctica, between the 1980/1981 and 1992/1993 seasons revealed siginificant changes in abundance of the 9 resident and 15 non-resident species. An estimated 4.85 million individual residents and 2.35 million individual non-residents were present each season. For resident and non-resident species, mean abundance was 3.75 and 1.81 birds/km2, and mean biomass was 6.67 and 1.70 kg/km2, respectively. Based on estimated abundances, the total consumption of marine resources by the seabird community within Prydz Bay ranged from 471,000 to 1.1 million tonnes (mean 752,000±176,000 tonnes) per 6-month summer, or between 2.02 and 4.53 kg/km2 per day (mean 3.23±0.76 kg/km2 per day). The mean energy flux to the seabird community within Prydz Bay each summer was 3.13*1012 kJ, (range: 2.0*1012 kJ–4.4*1012 kJ), of which 66% went to the resident species. Regional abundance and biomass estimates for resident and non-resident species were both negatively correlated; when the estimated abundance and biomass of resident species were high, those of non-resident species were low. Received: 4 January 1996/Accepted: 3 July 1996  相似文献   

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The impact of hydrological manipulation of an unfertilised, Dutch peat grassland area on plant species composition on ditch banks and in ditchwater was studied. The hydrological manipulation involved raising the groundwater level by admitting nutrient-poor, Ca-rich groundwater in one compartment, and by retaining precipitation in another compartment. A third compartment served as control.The plant species composition showed significant correlations with the following hydrochemical parameters: in bank vegetation with K+ concentration, and winter and summer groundwater levels, water depth and elevation; in aquatic vegetation with pH, the concentrations of Cl- organic-C and NH4 + water temperature and elevation.The number of terrestrial plant species increased after compartmentation from 97 to 122; 16 submerged and floating species were found. Most new terrestrial species probably emerged in response to cessation of fertilization and biomass removal, since they showed no preference for any compartment. Five species showed preference for the groundwater compartment and two for the rainwater compartment. Of the new terrestrial plants, seven were relatively rare: Carex panicea, C. oederi, C. pallescens, C. vesicaria, Galium uliginosum, Juncus acutiflorus and Stellaria uliginosa. Of the aquatic plants, eight were relatively rare: Chara globularis, two Callitriche spp., four potamogetonaceae and Ranunculus circinatus.This study indicates that hydrological manipulation of grassland systems in which fertilisation has ceased has profound effects on the vegetation in the ditches of these systems. Bank vegetation responds more slowly and to other hydrochemical factors than aquatic vegetation. Short-term responses in terms of increase in diversity of vegetation pattern and species richness are promising. Long-term responses are not yet known.  相似文献   

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H. W. Bain  Gary Goldthorpe 《CMAJ》1972,107(6):523-528
The University of Toronto''s Sioux Lookout Project is described in detail. The scheme is a collaborative one in which universities, governments, doctors, dentists, nurses, communities and consumers participate. After three years of operation it appears to be a feasible model for delivery of health care in a remote area under extremely adverse conditions. It is suggested that a modified version would be applicable to other underdoctored areas. The individual roles of the various participants are outlined. Universities, by giving some preference in their postgraduate training programs to doctors who have spent a year in practice, especially in remote areas, would make a major step towards correcting the maldistribution of doctors.  相似文献   

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Norovirus is a common cause of gastroenteritis, and is thought to be the causative agent in 68–90% of all gastroenteritis outbreaks. The seasonality of disease occurrence is sufficiently stereotyped to result in this disease being dubbed “winter vomiting disease.” The genesis of this seasonality has been obscure. We sought to identify environmental factors associated with Norovirus outbreaks in Toronto, Canada. We evaluated 253 outbreaks of gastroenteritis linked to Norovirus between November 2005 and March 2008. Poisson regression models were constructed to evaluate associations between average environmental exposures and case counts. A case-crossover approach was used to evaluate associations between acute changes in environment and outbreak risk. Case-crossover analysis indicated an association between low Lake Ontario temperature (≤4°C) (hazard ratio [HR], 5.61 [95% CI, 2.81–11.12]) and high flow (>2.5 m3/s) in the Don River (HR, 3.17 [95% CI, 2.30–4.36]), 1–7 days prior to case occurrence. For both exposure variables, the highest hazard ratios were found 24–48 h prior to case onset. Regression models provided further support for these patterns. The association between local watershed conditions and Norovirus outbreak risk suggest a source-water reservoir for this pathogen. We hypothesize that the reservoir may be maintained through the discharge of wastewater containing virus particles; wintertime seasonality may be explained by enhanced viral persistence at low temperatures.  相似文献   

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Background

Recent evidence indicated that gender disparity in child health is minimal and narrowed over time in India. However, considering the geographical and socio-cultural diversity in India, the gender gap may persist across disaggregated socioeconomic context which may be masked by average level. This study examines the dynamics of gender disparity in childhood immunization across regions, residence, wealth, caste and religion in India during 1992–2006.

Method

We used multi-waves of the cross-sectional data of National Family Health Survey conducted in India between 1992–93 and 2005–06. Gender disparity ratio was used to measure the gender gap in childhood immunization across the selected socioeconomic characteristics. Multinomial regression analysis was used to examine the gender gap after accounting for other covariates.

Result

Results indicate that, at aggregate level, gender disparity in full immunization is minimal and has stagnated during the study period. However, gender disparity – disfavouring female children – becomes apparent across the regions, poor households, and religion - particularly among Muslims. Adjusted gender disparity ratio indicates that, full immunization is lower among female than male children of the western region, poor household and among Muslims. Between 1992–93 and 2005–06, the disparity in full immunization had narrowed in the northern region whereas it had, astonishingly, increased in some of the western and southern states of the country.

Conclusion

Our findings emphasize the need to integrate gender issues in the ongoing immunization programme in India, with particular attention to urban areas, developed states, and to the Muslim community.  相似文献   

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生物制品GMP(WHO,1992)目录1.本指南范围2.原则3.人员4.厂房和设备5.动物设施及管理6.生产7.标签8.批加工记录(格式)和分发记录9.质量保证和质量控制1本指南范围本指南系作为《药品GMP》(见WHOTRS,NO.823)的补充。生...  相似文献   

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Exposure to soil‐borne contaminants can occur through ingestion, inhalation and/or dermal absorption. A study was undertaken to assess the relative frequency with which dermal exposures are predicted to pose the greatest risk attributable to contaminated soils in Superfund risk assessments. Screening of over 200 risk assessments from the period 1989–1992 resulted in identification of 37 sites at which projected lifetime excess cancer risks attributed to dermal contact with soil were greater than the nominal regulatory threshold of 1.10‐4. At 19 of these sites, the dermal/soil pathway is estimated to contribute the largest carcinogenic risk associated with surface soil contamination, and may therefore drive cleanup of that medium. At 9 of the sites, the dermal/soil pathway is predicted to present a higher carcinogenic risk than any other pathway. Chemical contaminant type and estimates of soil adherence and surface area exposed appear to be the primary factors that distinguish sites at which dermal/soil pathway carcinogenic risk estimates are elevated relative to other exposure pathways. Quantification of exposure parameters, especially those related to behavior, remains a significant need.  相似文献   

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Announcement

3rd International Conference on Mathematical Population Dynamics 1–5 June 1992, University of Pau, France  相似文献   

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《Inorganica chimica acta》2006,359(5):1421-1426
Synthesis, structural characterization, and spectroscopic and magnetic properties of three new cyano-bridged 3d–4f bimetallic complexes, LnIII(DMF)4(H2O)3CrIII (CN)6 · nH2O (Ln = Nd, Sm, Gd), have been described. The Nd–Cr complex crystallizes in the monoclinic P21/n space group with the following unit cell parameters: a = 20.063(7) Å, b = 8.967(4) Å, c = 18.023(6) Å, b = 96.12(3)°, V = 3224(2) Å3, and Z = 4. The neodymium (III) ion, which adopts anti-prism eight-coordination environment, is linked to the [CrIII(CN)6]3− moiety through a bridging cyanide ligand with Nd–N = 2.550(4) Å and Nd–N–C = 164.4(4)°. The variable-temperature (0.5 T at 2–300 K) and variable-field (0–5 T at 2 and 5 K) magnetic measurements reveal that the weak interaction of Gd–Cr complexes differs from that of Nd–Cr and Sm–Cr ones mainly because of the lack of orbital angular momentum. The XPS and diffuse reflectance electronic spectra were also measured to discuss charge transfer transitions concerning π-backdonation from the viewpoint of magneto-optical functions.  相似文献   

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