首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
2.
3.
4.
5.
The coexistance of tuberculous infection (TB-infection) and lung cancer in patients treated in Pulmonary Department of Medical Academy in Lublin during last ten years (1990-2000) has been evaluated. Inclusion criteria involved: aging from 50 to 80 years, tobacco smoking, tuberculous infection in present or in past, lung cancer. All analyzed patients (32 males, 13 females) were heavy smokers (from 10 to 70 cigarettes per day, during at least 5 years). 27 patients were suffered from lung tuberculosis in past, the rest of them had active tuberculous infection. In 19 cases we detected carcinoma planoepitheliale, in 13 cases carcinoma macrocellulare, in 7 cases carcinoma microcellulare and in 6 cases adenocarcinoma. We concluded, that increased occurrence of lung cancer in TB reinfected patients may be connected with immunodepression caused by chronic TB infection. In patients with new active TB-infection in whom the clinical status and chest X-ray were getting worse in spite of antituberculotic treatment recommended procedures for cancer diagnosis were performed. We suggest that bad results of anti-tuberculotic treatment in TB-infected patients are not always caused by bactericidal resistance. In these cases, the proper diagnosis of lung cancer should be considered.  相似文献   

6.
Twelve species are considered within the Afrotropical genus Strigivenifera Hering, 1937, and ten of them are described as new ones: S. eborea sp. n.,S. livingstonei sp. n., S. marina sp. n., S. tanja sp. n., S. ocellaris sp. n., S. cruisa sp. n., S. bartschi sp. n., S. oris sp. n., S. tatooifera sp. n., and S. neo sp. n. The species S. albidiscalis (Hampson, 1910) is raised from synonymy with S. venata (Aurivillius, 1895) and considered as a separate species.  相似文献   

7.
The paper gives a review on the recent development of bioprocess engineering. It includes monitoring of product formation processes by flow injection analysis, various types of chromatographic and spectroscopic methods as well as by biosensors. The evaluation of mycelial morphology and physiology by digital image analysis is discussed also. It deals with advanced control of indirectly evaluated process variables by means of state estimation/observer, with the use of structured and hybrid models, expert systems and pattern recognition for process optimization and gives a short report on the state of the art of metabolic flux analysis and metabolic engineering.  相似文献   

8.
Semagn K 《Hereditas》2002,137(2):149-156
The genetic relationships among ten types of endod (Phytolacca dodecandra) cultivated by the Institute of Pathobiology of the Addis Ababa University to combat the disease bilharzia in Ethiopia were studied using morphology and molecular markers. A total of 18 morphological characters, 194 amplified fragment length polymorphism (AFLP) and 42 random amplified polymorphic DNA (RAPD) markers were used to determine genetic proximity between types. Genetic distance and cluster analysis of the AFLP data revealed the lack of genetic difference between E47 and E48 but relatively wider genetic difference among the other endod types. Cluster and principal component analyses performed on the AFLP and RAPD markers demonstrated the presence of distinct separation of E56 but not that of E44 from the others. The AFLP and RAPD data, thcrefore, did not support the hypothesis that the superiority of E44 in agronomic traits and molluscicidal potency is linked to its distinct genetic difference from the other endod types. Matrices correspondence tests demonstrated the presence of greater correspondence between AFLP and RAPD data (r = 0.842) but not between the morphology and that of AFLP and RAPD. This indicates the correspondence more between the two DNA markers systems than either of them with morphological traits. The cophenetic correlation coefficients also revealed poor fit for morphology (r = 0.716), good fit for RAPD (r = 0.872) and very good fit for AFLP (r = 0.975), reflecting the hyper-variability and higher resolving power of AFLP.  相似文献   

9.
The tambaqui, Colossoma macropomum, native to Brazil, is widely used in aquaculture systems. We developed a multiplex PCR panel for this species, comprising 12 microsatellite loci. This panel was used to genotype 73 specimens collected from Juruti, a city in the Brazilian Amazon. The mean number of alleles per locus was 8.8, the mean observed heterozygosity was 0.76, and the combined power of discrimination and the combined power of exclusion were 0.99999999999999993 and 0.999991762, respectively. We observed no significant deviation from Hardy-Weinberg equilibrium in this population. All amplified alleles were clearly typed, and easily interpretable results were obtained. This method will be useful for paternity analysis, population genetics and conservation studies, as well as for selective breeding programs for C. macropomum.  相似文献   

10.
11.
12.
13.
The present study evaluates trends in the prevalence of overweight and obesity in relation to gender and area of residence between two cohorts of students aged 11–13 years in Sicily. The analysis was performed on 1,839 schoolchildren, with 924 and 915 children being studied in 1999–2001 and 2009–2010, respectively. The children who were enrolled during 2009–2010 had significantly higher body mass indexes (BMI), BMI z-scores, and waist circumferences than the children who were studied during 1999–2001 (p<0.0001 for all); these differences was also observed when the cohort was subdivided according to gender or residence area The prevalence of obesity increased significantly from 7.9% in 1999–2001 to 13.7% in 2009–2010 (p<0.0001), whereas thinness decreased significantly from 10.1% to 2.3% (p<0.0001) in the same periods. The increase of trends in the prevalence of obesity was significantly higher in males (9.7% vs. 17.6%, p = 0.0006) than in females (6.3% vs. 9.8%, p = 0.04) and was slightly higher in urban areas (8.8% vs. 14.3%, p = 0.002) than in rural areas (7.8% vs. 13.0%, p = 0.012). The male gender was associated with a higher risk of being overweight or obese (odds ratio: 1.63; 95% confidence intervals: 1.24–2.15; p = 0.0005) in 2009–2010 than in 1999–2001, after adjusting for age and the residence area. In conclusion, this study showed an increasing trend in the prevalence of overweight and obesity in Sicilian schoolchildren during the last decade and that this trend was related to gender, age and the area of residence. More specifically, our data indicated that the prevalence of obesity increased by 5.8%, the prevalence of thinness decreased by 7.8% and the prevalence of normal-weight children did not change over the course of a decade. These results suggest a shift in the body weights of Sicilian children toward the upper percentiles.  相似文献   

14.
In recent years, several publications in computer science journals have proposed new heuristic methods for parsimony analysis. This contribution discusses those papers, including methods highly praised by their authors, such as Hydra, Sampars and GA + PR + LS. Trees of comparable or better scores can be obtained using the program TNT, but from one to three orders of magnitude faster. In some cases, the search methods are very similar to others long in use in phylogenetics, but the enormous speed differences seem to correspond more to poor implementations than to actual differences in the methods themselves.  相似文献   

15.
Michael Jeffries 《Ecography》2008,31(6):765-775
Ponds are important habitats within many landscapes because of the diversity of wildlife they support. This arises in part because of the heterogeneity of ecological communities found in neighbouring ponds but this variation has proved difficult to explain. Chance and unrecorded historic events have often been emphasised as explanations. This study describes the development of spatial heterogeneity and the role of historic events in the development of pond plant macrophyte communities from the ponds’ creation until ten later using thirty small, adjacent temporary ponds in Northumberland. Plant communities showed significant spatial variation from the first year onwards. Metacommunity spatial patterns changed over time but even after ten years several distinct macrophyte communities persisted in different ponds. The outcome was that a greater variety of pond communities persisted than was likely if a single, larger pond had been created on the site. The spatial patterns of the plants communities were compared to spatial variation of summer dry‐phase and winter inundation. Macrophyte heterogeneity appeared to result from deterministic change which would have been difficult to detect in a snap‐shot survey not knowing the history of the ponds. Winter inundation showed significant spatial trends every year which mirrored the changing distribution of macrophyte communities between ponds. The proximate influence of the inundation is ultimately determined by the position of each pond in the landscape so that the marked spatial and temporal heterogeneity of plant communities was strongly influenced by small scale variation in hydrology. The results suggest that the heterogeneity of pondlife across a landscape may be deterministic when recorded over a longer time period and not due to chance, but that the determining environmental factors are highly contingent on the locality of the pond.  相似文献   

16.
During the past 2 decades, considerable progress has been made in the study of bird semiochemistry, and our goal was to review and evaluate this literature with particular emphasis on the volatile organic constituents. Indeed, since the importance of social chemosignaling in birds is becoming more and more apparent, the search for molecules involved in chemical communication is of critical interest. These molecules can be found in different sources that include uropygial gland secretions, feather-surface compounds, and molecules from feces and skin. Although many studies have examined the chemical substances secreted by birds, research on bird chemical communication is still at the start, so new strategies for collecting samples and development of new methods of analysis are urgently required. As a first step, we built a database that brings together potential semiochemicals, using a unique chemical nomenclature for comparing different bird species and also for referencing the different classes of substances that can be found in order to adapt future parameters of analysis. The most important patterns of the wax fraction of preen secretions are highlighted and organized in an ordered table. We also draw up a list of various combinations of sampling and analytical techniques, so that each method can be compared at a glance.  相似文献   

17.
The authors, from their personal experience arising from 766 consultations, show that the percentages of marriages or procreations in subjects themselves suffering from a disorder, or with affected relatives, are independent of the risk estimated for their offspring. The procreation rate in couples with affected children is lower in high risk cases and depends also on the family composition. It appears that this procreation is voluntary in the great majority of cases because there were very few terminations of pregnancy among the couples seen before procreation. The estimated risks correspond to the risks observed but the authors insist that there is a relatively high proportion (4.4 per cent) of children born with a disorder different from that which motivated the consultation.  相似文献   

18.
From 1975 through 1986, repeated preventive oncologic check-ups were carried out in the District Sumperk. In the course of the check-ups, 49,426 persons were examined. The examinations were aimed at surveillance of initial stadium of cancers as well as at detection of other serious chronic diseases. The results of the check-ups form a large database suitable for a number of epidemiological analyses. In this article, methods of the data collection are described, individual data items are characterized and their summary is presented in tables. Utilization of the database is proposed in specified types of epidemiological studies.  相似文献   

19.
The aim of this study was to describe the forest vegetation along an altitudinal transect running from 158 m to 1220 m (treeline) in the Mount Field National Park, Tasmania. Eighteen 1 ha plots were sampled along this transect, using a modified point-centred quarter method for species composition and density. Size frequency distributions were used to calculate basal areas. Estimates of relative density, frequency and basal area for each species were combined in to an importance value. The altitudinal ranges of all woody species were determined. The altitudinal temperature lapse rate was measured, and data on soil pH obtained. The initial ‘direct gradient’ analysis revealed relatively well marked discontinuities in the vegetation which were further examined by ordination and classification techniques. The latter provided a simple threefold classification into altitudinal zones. The lower zone reaches from the Park entrance (158 m) to between 600 and 670 m, and comprises tall open forest dominated by Eucalyptus regnans and/or E. obliqua and with a ‘wet sclerophyll’ understorey characterized by Olearia argophylla. The middle zone stretches from c. 670 to 940 m and comprises closed rainforest or ‘mixed’ forest (i.e. with senescent emergent eucalypts) dominated by Nothofagus cunning hamii and Atherosperma moschatum. This zone is characterized by the absence of O. argophylla and the presence of Phyllocladus aspleniifolius. The upper part of this zone constitutes an interdigitating transition to the subalpine forests, usually dominated by E. coccifera and occurring on suitable sites between c. 880 m and the timberline. The transition to subalpine forests is associated with a marked decline in basal area. Species richness (of woody plants) increases with altitude to reach a peak in the sub-alpine zone. This trend is the reverse of that normally encountered elsewhere in the world, and is mainly due to relatively high α and β diversities in the shrub stratum of this zone. The significance of fires, aspect and substrate is discussed in relation to the variations in composition within each zone. The low diversity of Nothofagus-dominated rainforest is thought to be due, in part, to the intense competitive thinning in the eucalypt re-growth phase following burning, and the subsequent ‘capture’ of the Eucalyptus niche by Nothofagus. It is speculated that, in Tasmania, the downhill migrations during the cooling phases of the Pleistocene were associated with extinctions of lowland forest taxa, while uphill migrations during warming phases were associated with speciation on the plateaux of the present subalpine zone. This hypothesis implies that the relative proportions of land area available at different altitudes, now and in the past, have determined the relative rates of speciation and extinction, and hence the altitudinal gradients of species richness.  相似文献   

20.
The ability to rapidly distinguish trichothecene chemotypes in a given species/population of the genus Fusarium is important due to significant differences in the toxicity of these secondary metabolites. A multiplex PCR assay, based on primer pairs derived from the Tri3, Tri5 and Tri7 genes of the trichothecene gene cluster was established for the identification of the different chemotypes among Fusarium graminearum, F. culmorum and F. cerealis. Using the selected primers, specific amplification products of 625, 354 and 708 bp were obtained from Fusarium isolates producing nivalenol, 3-acetyl-deoxynivalenol and 15-acetyl-deoxynivalenol, respectively. Moreover, the multiplex PCR was successfully used to identify the chemotype of the Fusarium species contaminating wheat kernels. Four picograms of fungal DNA were found to be necessary to obtain a visible amplification product.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号