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11.
The content of herbaceous pollen in the atmosphere depends on the vegetal cover, climate and the weather and geographical conditions. The aim of the study reported here was to compare aerobiological data obtained from pollen monitoring stations located at sites differing with respect to their flora and microclimate – i.e. a town and a rural area. A volumetric method was used for sampling. In each microscopic preparation 12 vertical strips corresponding with 2-h intervals were analysed. A 90% method was used to determine the pollen season. The results were statistically verified using the u test and the Kolmogorov-Smirnov, Spearman and Wilcoxon tests. Higher values of the Seasonal Pollen Index (SPI), higher daily average concentrations and higher peak values were recorded in the rural area. An analysis of intradiurnal variations of airborne pollen showed that apart from the Poaceae the number of pollen grains in the air began to increase earlier in the day in the rural area; in the case of Rumex and Ambrosia, the maximum values also appeared a few hours earlier. For all the taxa investigated, the analysis of correlation showed a significant association between the daily average concentrations at both sites. The weakest association occurred for Plantago lanceolata; for all other taxa, the determination coefficients (R 2) were high. The results of the Wilcoxon test showed that, despite the strong positive association between daily concentrations of the pollen types investigated, there were differences in mean pollen concentrations in the overlapping pollen season. Mean concentrations of Poaceae and Rumex airborne pollen were significantly higher in the rural area in both years, and those of Urtica and P. lanceolata were significantly higher only in 2002.  相似文献   
12.
The virulence of F. tularensis is often associated with its ability to grow in macrophages, although recent studies show that Francisella proliferates in multiple host cell types, including pulmonary epithelial cells. Thus far little is known about the requirements for killing of F. tularensis in the non-macrophage host cell types that support replication of this organism. Here we sought to address this question through the use of a murine lung epithelial cell line (TC-1 cells). Our data show that combinations of the cytokines IFN-γ, TNF, and IL-17A activated murine pulmonary epithelial cells to inhibit the intracellular growth of the F. tularensis Live Vaccine Strain (LVS) and the highly virulent F. tularensis Schu S4 strain. Although paired combinations of IFN-γ, TNF, and IL-17A all significantly controlled LVS growth, simultaneous treatment with all three cytokines had the greatest effect on LVS growth inhibition. In contrast, Schu S4 was more resistant to cytokine-induced growth effects, exhibiting significant growth inhibition only in response to all three cytokines. Since one of the main antimicrobial mechanisms of activated macrophages is the release of reactive nitrogen intermediates (RNI) via the activity of iNOS, we investigated the role of RNI and iNOS in Francisella growth control by pulmonary epithelial cells. NOS2 gene expression was significantly up-regulated in infected, cytokine-treated pulmonary epithelial cells in a manner that correlated with LVS and Schu S4 growth control. Treatment of LVS-infected cells with an iNOS inhibitor significantly reversed LVS killing in cytokine-treated cultures. Further, we found that mouse pulmonary epithelial cells produced iNOS during in vivo respiratory LVS infection. Overall, these data demonstrate that lung epithelial cells produce iNOS both in vitro and in vivo, and can inhibit Francisella intracellular growth via reactive nitrogen intermediates.  相似文献   
13.
Trichomonas vaginalis can be infected with double-stranded RNA (dsRNA) viruses known as T. vaginalis virus (TVV). This viral infection may have important implications for trichomonal virulence and disease pathogenesis. The objective of this study was to determine the possible correlation between the T. vaginalis genetic polymorphism and the isolate infection with TVV. The Random Amplified Polymorphic DNA (RAPD) technique was used to determine genetic differences among 37 isolates of T. vaginalis using a panel of 30 random primers and these genetic data were correlated with the infection of isolates with TVV. The trees drawn based on RAPD data showed significantly association with the presence of TVV (P = 0.028) demonstrating the existence of concordance between the genetic relatedness and the presence of TVV in T. vaginalis isolates. This result could point to a predisposition of T. vaginalis for the viral enters and/or survival.  相似文献   
14.
The investigated problem was whether and to what an extent the elements of weather conditions were associated with changes in the concentration of Ambrosia pollen in air. The study was carried out in the years 1997–2004 using the volumetric method. Ragweed did not occur in the flora of the town of Rzeszów and its vicinity, but every year its pollen occurred at concentrations considerably exceeding the threshold values for the allergic response. The pollen seasons usually began from near the end of August to the first part of September. The values of daily concentrations varied greatly: days without pollen grains being frequently noted while single grains occurred long before and after the season. The effect of the elements of weather on changes in the concentration of pollen in the air was slight. Taking into account all meteorological parameters, it can be stated that an increase in the number of pollen grains is connected with increased temperature and higher wind speeds, but negatively correlated with humidity and rainfall. These relationships can usually be explained by the effects of the type of weather taking place over the wider region. The analysis of the results showed that pollen was probably transported from distant regions. The mean angle at which the greatest pollen concentrations were recorded corresponded to the SE wind direction. The analysis of synoptic phenomena during the pollen season confirms the thesis about the long-distance transport from the south, southeast and southwest. A close dependence was also found between the starting date of the season and the sum of maximum temperatures and the sum of differences between the maximum and minimum temperatures.  相似文献   
15.
16.
Burkholderia cenocepacia is a significant problem in individuals with cystic fibrosis and is a member of the B. cepacia complex of closely related antibiotic resistant bacteria. A salicylate-regulated antibiotic efflux operon has been identified in B. cenocepacia and one of its four genes, llpE, is without parallel in previously reported efflux operons. PCR amplification and sequencing of llpE from B. cepacia complex isolates demonstrated the highest prevalence in B. cenocepacia with a high degree of sequence conservation. While at least one non-synonymous mutation was identified between isolates from different genomovars, only synonymous differences were identified within the IIIA and IIIB sub-groups of B. cenocepacia. Structural modeling suggests that LlpE is a member of the alpha/beta hydrolase enzyme family. Identification of strong structural homology to hydrolases and a high degree of conservation in B. cenocepacia suggests an enzymatic function for LlpE, benefiting survival in the cystic fibrosis lung.  相似文献   
17.
Deforestation of tropical forests is threatening monkey biodiversity and their health status, dependent of an ecologically undisturbed area. To asses this relationship, we analyzed parasite occurrence in their intestines. The study was conducted at the Estación Biológica La Suerte (EBLS), Limón, Costa Rica. The group of white-faced capuchin monkeys (Cebus capucinus) was observed between March and December of 2006. A total of 75 feces samples were obtained. Once a sample was collected, the eaten plant type was identified to family and species level, and feces were processed in the laboratory to determine parasite incidence. Results showed that Moraceae was the most represented family in the samples. Among parasites, Strongyloides spp. and Acanthocephala were the most common. Positive prevalence of parasites was found similar and independent of sex and age of capuchin individuals. Microsporids were mainly reported in feces associated with Piperaceae. A low presence of these parasites was found in samples associated with Myrtaceae, with possible anti-parasite active components. The occurrence of parasites was relatively high in EBLS, when compared to other regions in Costa Rica. The higher occurrence of parasites observed in capuchins at EBLS may be due to the fact that this rain forest is surrounded by areas affected by human activities. We suggest the promotion of research in neotropical primates parasitology, for a better comprehension of the parasite-host relationship, and in a long term, being able to understand the ecosystems where they coexist, and consequently, preserve the biodiversity of the whole region.  相似文献   
18.
Trichomonas vaginalis can be naturally infected with intracellular Mycoplasma hominis. This bacterial infection may have implications for trichomonal virulence and disease pathogenesis. The objective of the study was to report the presence of M. hominis in Cuban T. vaginalis isolates and to describe the association between the phenotype M. hominis infected with RAPD genetic polymorphism of T. vaginalis. The Random Amplified Polymorphic DNA (RAPD) technique was used to determine genetic differences among 40 isolates of T. vaginalis using a panel of 30 random primers and these genetic data were correlated with the infection of isolates with M. hominis. The trees drawn based on RAPD data showed no relations with metronidazole susceptibility and significantly association with the presence of M. hominis (P=0.043), which demonstrates the existence of concordance between the genetic relatedness and the presence of M. hominis in T. vaginalis isolates. This result could point to a predisposition of T. vaginalis for the bacterial enters and/or survival.  相似文献   
19.
Previous studies have shown that ragweed pollen arrives in Poland from sources in the south, in Slovakia, the Czech Republic, Hungary and Austria. It is likely that ragweed pollen also arrives from sources in the southeast (e.g. Ukraine). This hypothesis was investigated using 13 years of pollen data and back-trajectory analysis. Ambrosia pollen data were collected at three sites in Poland, Rzeszów, Kraków and Poznań. The amount of ragweed pollen recorded at Rzeszów was significantly higher than in Poznań and Kraków. This can be related to either a higher abundance of local populations of Ambrosia in south-east Poland or the proximity of Rzeszów to foreign sources of ragweed pollen. The combined results of pollen measurements and air mass trajectory calculations identified plumes of Ambrosia pollen that were recorded at Rzeszów, Kraków and Poznań on 4 and 5 September 1999 and 3 September 2002. These plumes arrived at the pollen-monitoring sites from an easterly direction, indicating sources of Ambrosia pollen in eastern Poland or Ukraine. This identifies Ukraine as a possible new source of ragweed pollen for Poland and therefore an important source area of Ambrosia pollen on the European Continent.  相似文献   
20.
Background: Preeclampsia, a pregnancy disorder characterized by hypertension and proteinuria, represents the leading cause of fetal and maternal morbidity and mortality in developing countries. The identification of novel and accurate biomarkers that are predictive of preeclampsia is necessary to improve the prognosis of patients with preeclampsia.

Objective: The objective of this study is to evaluate the usefulness of nine urinary metalloproteinases to predict the risk of preeclampsia development.

Methods: MMP-1, MMP-2, MMP-3, MMP-7, MMP-8, MMP-9, MMP-10, MMP-12 and MMP-13 were analyzed in urine (early-pregnancy) from 17 women predicted to develop preeclampsia and 48 controls using the Bio-Plex Pro-Human MMP panel (Bio-Rad, Hercules, CA).

Results: Urinary MMP-2 showed differences between groups which allowed us to calculate an increased risk for PE development of up to 20 times among the study population.

Conclusion: Increased urinary concentration of MMP-2 at 12 and 16 weeks of gestation predicted an increased risk of developing preeclampsia in the study population.  相似文献   

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