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71.
72.
Gołkowski F Buziak-Bereza M Trofimiuk M Bałdys-Waligórska A Szybiński Z Huszno B 《Public health nutrition》2007,10(8):799-802
OBJECTIVE: To assess the prevalence of hyperthyroidism just after implementation of iodine prophylaxis among adults from an area with iodine deficiency. STUDY DESIGN AND SUBJECTS: A total of 1648 adults (age 16 years and older) were sampled from an area of southern Poland during two nationwide epidemiological surveys. Of these, 1424 adults with negative medical history for thyroid disorders qualified for final analysis. The authors compared thyroid dysfunction in participants prior to (1989-1990) and after implementation of iodine prophylaxis (1997-1999). SETTING: The southern part of Poland. RESULTS: We found an increase in the serum concentration of anti-thyroid microsomal antibodies from 4.9% in the years 1989-1990 to 12.1% after introduction of iodised household salt (P < 0.0001). The prevalence of hyperthyroidism (defined as thyroid-stimulating hormone < 0.4 microU ml- 1) significantly increased in the equivalent period from 4.8 to 6.5% (P = 0.009). CONCLUSIONS: We concluded that a sudden rise in iodine intake after implementation of iodine prophylaxis among adults from the area with iodine deficiency may lead to an increase in thyroid autoimmunity and prevalence of hyperthyroidism. Those possible early side-effects appear to be only temporary and are acceptable when compared with the evident benefits of adequate iodine intake. 相似文献
73.
The aim of this research was to evaluate the amount of woody debris (m3/ha) on the forest floor and the associated wood-colonizing fungi. The study was performed in the Taborz region, known for its Scots pine provenance experiments, against the background of a recently launched Polish legislation to protect the biodiversity on the forest floor in managed (harvested) stands. We investigated a managed stand (136-years-old) and the reserve stand ‘Sosna Taborska’(261-years-old). In the reserve stand, the mean volume of woody debris was six times higher than in the managed forests, i.e. 65 versus 11 m3/ha. In addition, in the reserve stand, the number of fungi taxa colonizing the dead wood was larger than in the managed stands, with a higher number of fruitbodies. Total fungal richness was higher in the reserve than in the managed stand, i.e. 28 versus 12 species. The dominant taxa at both sites were Fomitopsis pinicola and Fomes The aim of this research was to evaluate the amount of woody debris (m^3/ha) on the forest floor and the associated wood-colonizing fungi. The study was performed in the Taborz region, known for its Scots pine provenance experiments, against the background of a recently launched Polish legislation to protect the biodiversity on the forest floor in managed (harvested) stands. We investigated a managed stand (136-years-old) and the reserve stand ‘Sosna Taborska’(261-years-old). In the reserve stand, the mean volume of woody debris was six times higher than in the managed forests, i.e. 65 versus 11 m^3/ha. In addition, in the reserve stand, the number of fungi taxa colonizing the dead wood was larger than in the managed stands, with a higher number of fruitbodies. Total fungal richness was higher in the reserve than in the managed stand, i.e. 28 versus 12 species. The dominant taxa at both sites were Fomitopsis pinicola and Fomes fomentarius, although some taxa were only found in the reserve (e.g., Stereum hirsutum). The volume of woody debris as well as the diversity of fungi in the managed stand were lower than in the reserve, albeit greater than in other Scots pine stands in Poland. These results testify to the gains in biodiversity yielded by the management conservation management approach at the reserve stand. 相似文献
74.
As currently practiced, genetic engineering of monocots requires the use of selective agents, such as herbicides and antibiotics, and marker genes for resistance to favor the multiplication of the initially transformed cells. In the present paper we have used “minimal gene cassettes” and positive selection to generate transgenic durum wheat lines free of herbicide and antibiotic resistance marker genes. Two biolistic transformation experiments were carried out using three “minimal gene cassettes” consisting of linear DNA fragments each excised from the source plasmids. The targeted trait genes were two bread wheat sequences encoding the Dx5 and Dy10 high-molecular-weight (HMW) glutenin subunits, which have been associated with superior bread-making quality and which are absent from durum wheats. The positive selectable marker was the Escherichia coli phosphomannose isomerase (pmi) gene, whose product catalyzes the reversible interconversion of mannose-6-phosphate and fructose-6-phosphate, allowing plant cells to utilize mannose as a carbon source. PCR assays of genomic DNA from regenerated plants identified 15 T0 plants that contained the pmi marker gene for an overall transformation efficiency of 1.5%, which is similar to biolistic transformation efficiencies of durum wheat with intact circular plasmids. Line TC-52, which initially contained pmi, non-expressed 1Dx5, and expressed 1Dy10 HMW glutenin subunit transgenes, was further investigated. PCR was used to follow inheritance of the pmi marker gene and 1Dx5 from the T1 to T3 generations. Transgene expression was monitored by the chlorophenol-red assay for pmi and SDS-PAGE of seed proteins for 1Dy10. From these analyses, we observed that the 1Dy10, 1Dx5 and pmi transgenes were not linked, allowing us in the T3 generation to identify 1Dy10 transgenic segregants that contained no marker or silent 1Dx5 transgenes. Homozygotes containing and expressing only the 1Dy10 transgene were identified in the T4 generation. These experiments show that it is possible to combine biolistic transformation by minimal gene cassettes with genetic segregation to make marker-free transgenic wheat plants with new traits. 相似文献
75.
Sylwia Jarmołowicz Zdzisław Zakęś Andrzej Siwicki Elżbieta Terech-Majewska Agata Kowalska Konrad Partyka Marek Hopko 《Aquaculture International》2013,21(4):939-945
The present study examined the influence of extract obtained from the interior of cells of yeast, Saccharomyces cerevisiae (NuPro®), on the growth, proximate composition, nonspecific cellular and humoral defense mechanisms, and protection against furunculosis in pikeperch (Sander lucioperca). It was noted that eight weeks of supplementation with 40 g of NuPro® kg?1 feed (containing approximately 0.22 % exogenic nucleotides) enhanced pikeperch innate immunity. Increased serum lysozyme activity and total Ig levels (P < 0.05) were noted in the NuPro®-fed group, which indicated the activation of nonspecific humoral defense mechanisms. Brewer’s yeast extract also stimulated nonspecific cellular defense mechanisms as indicated by the increased metabolic activity of blood phagocytes and pronephric macrophages, and in the increased intracellular killing activity of phagocytes and proliferative responses of T and B lymphocytes (P < 0.05). Additionally, reduced mortality (15 %) after the in vivo challenge with pathogenic Aeromonas salmonicida suggested that NuPro® activated nonspecific protection against furunculosis in pikeperch. The experimental feed did not have a significant impact on the growth or proximate composition of the fish (P > 0.05). 相似文献
76.
77.
Michał Czopowicz Olga Szaluś‐Jordanow Marcin Mickiewicz Agata Moroz Lucjan Witkowski Iwona Markowska‐Daniel Daria Reczyńska Emilia Bagnicka Jarosław Kaba 《Animal Science Journal》2018,89(9):1364-1370
We carried out this study to determine for how long small ruminant lentivirus (SRLV)‐specific antibodies can be detected by three commercial ELISA kits in goat kids after suckling infected does in field conditions. Forty‐one kids born to SRLV‐seropositive asymptomatic does were blood sampled prior to colostrum consumption, and then weekly for 6 months in total. The sera were screened with three commercial ELISA kits: whole‐virus ELISA (wELISA), recombinant transmembrane and capsid antigen ELISA (TM/CA‐ELISA), and surface antigen ELISA (SU‐ELISA). All but one kid were seronegative in all three ELISAs right after birth. At the age of 1 week all kids turned seropositive in wELISA, 39 kids (95%) in TM/CA‐ELISA, and 35 kids (85%) in SU‐ELISA. All seropositive kids turned seronegative in wELISA by the 15th week, and in SU‐ELISA by the 19th week (median of 8 weeks in both ELISA), whereas in TM/CA‐ELISA five kids (13% of 39 initially seropositive) were still seropositive at the age of 6 months (median of 11 weeks). Antibody levels at the age of 1 week proved significantly linked to the duration of maternal antibodies in all three ELISAs and could be employed to predict for how long maternal antibodies would remain detectable. 相似文献
78.
79.
Rhind N Chen Z Yassour M Thompson DA Haas BJ Habib N Wapinski I Roy S Lin MF Heiman DI Young SK Furuya K Guo Y Pidoux A Chen HM Robbertse B Goldberg JM Aoki K Bayne EH Berlin AM Desjardins CA Dobbs E Dukaj L Fan L FitzGerald MG French C Gujja S Hansen K Keifenheim D Levin JZ Mosher RA Müller CA Pfiffner J Priest M Russ C Smialowska A Swoboda P Sykes SM Vaughn M Vengrova S Yoder R Zeng Q Allshire R Baulcombe D Birren BW Brown W Ekwall K Kellis M Leatherwood J Levin H Margalit H Martienssen R 《Science (New York, N.Y.)》2011,332(6032):930-936
80.
Herring ( Clupea harengus) (as well as sprat and mackerel) is a fish species intensively harvested by the Polish fishing fleet. Its relatively low price and the habits of Polish consumers contribute to its high economic importance in Poland. Among 125.6 thousand tons of marine fish harvested in 2006, herring constituted 22.2 thousand tons (including 7.6 thousand tons harvested from the North Sea). Fish are usually subjected to various culinary treatments, which can influence the concentrations of contaminants in final products. Therefore, the present study aimed at determining the effect of three non- ortho-polychlorinated biphenyl (PCB) congeners (PCB 77, PCB 126, and PCB 169) and three mono- ortho-PCB congeners (PCB 114, PCB 156, and PCB 157) in the tissues of herring slices. Concentrations of dry matter and lipids in the final product were increased by 15.9 and 20.5%, respectively. Brining, which preceded the process of smoking, did not significantly influence concentrations of PCB congeners in herring slices. However, smoking resulted in significant ( p < 0.05) changes in concentrations of three non- -ortho PCBs. The biggest dynamics of losses in relation to smoking duration was observed for PCB 77 (30.2%). For PCB 126, the biggest losses occurred after 1 h of drying, followed by slight changes after 1.5 and 2 h of proper smoking and another increase of losses in the final product after 2.5 h. The duration of smoking did not significantly influence PCB concentrations in wet weigh, as their losses in lipids were much bigger. The observation is derived from strong negative correlations between concentrations of the congeners in lipids and lipid concentrations in herring slices during hot smoking ( r ranging from -0.824 to -0.950). Although the lipid concentration in the smoked fish increased, the PCB content diminished. It shows that during drying of the fish slices, PCBs codistilled with water vapor, settling on the walls of the smoking chamber and smoking trolleys. During the proper smoking, the compounds released with the smoke back to the smoking chamber and settled on the surface of smoked fish together with the disperse phase of the smoke (aerosol). Hot smoking contributed to a reduction of toxic equivalents (TEQs) by 22.7% (converted into lipids 41.9%), and in the final product, it amounted to 0.0188 +/- 0.0023 ng TEQ/kg of wet weight (0.0977 +/- 0.0064 ng TEQ/kg of lipids). The reduction was significantly higher than resulting from hot smoking of mackerel slices, when TEQs were reduced by 17.9% wet weight (converted into lipids 31.7%). 相似文献