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101.
Consumption of poultry contaminated with Campylobacter jejuni has been recognized worldwide as the leading cause of campylobacteriosis. Therefore, the aim of our study was to investigate the prevalence and genotype diversity of Campylobacter jejuni in poultry meat intended for consumption in Split and Dalmatia County, which is the second biggest County in Croatia. Furthermore, we also wanted to discover possibly stable clones of C. jejuni appearing in different samples and periods of time, which would indicate their ability to persist in or adapt to poultry. In the period from March 2008 until June 2010, 834 samples of poultry from various sources were examined using a surface swab technique. Isolation of C. jejuni was performed by Preston broth and Karmali agar. Identification of the isolates was carried out using biochemical tests. C. jejuni was found in 84 of 574 chicken samples (14.6%) and in nine of 260 samples of turkey (3.5%). Pulse‐field gel electrophoresis (PFGE) was used to analyse 61 obtained isolates using SmaI and KpnI. Of 22 different macrorestriction profiles (MRP) that were found, five were detected in poultry from both different locations and periods of time. Samples from 11 locations were found to be contaminated with more than two different genotypes of C. jejuni. Interestingly, the same MRP were found both in poultry declared to be of domestic origin and in the poultry imported from abroad. The prevalence of C. jejuni in poultry samples was in accordance with previously reported results. Genotypic analysis indicated that the population of C. jejuni in Split and Dalmatia County was diverse and that multiple strains of C. jejuni could be found in the same poultry samples. Furthermore, the same genotypes were identified from the samples obtained from different locations and periods of time, which could support the theory of a global existence of certain MRP that are able to persist in or adapt to poultry.  相似文献   
102.
Resistance to plant disease is often specific and metabolites and receptors contributing to this specificity may have specific structures. However, simple, structurally-unrelated compounds induce systemic resistance in unrelated plants to diverse pathogens including fungi, bacteria and viruses. Both resistance and induced systemic resistance (ISR) are associated with the rapid accumulation of the same structurally unrelated putative defense compounds that have diverse functions. It has been suggested that cultivar (race)-specific resistance is initiated by the specific interaction of a pathogen product (or pathogen induced product) and a plant receptor. However, restricted infection by pathogens can result in ISR and many different compounds can cause ISR. It is thus evident that there are both specific and non-specific routes to the master switch for ISR and there may be more than one master switch. Are reactive oxygen species and free radicals regulating the master switch(es) via both routes? It is also evident there are many switches, other than the master switch. Adding to the complexity of resistance and ISR are the observations that different compounds and pathways may mediate different biochemical resistances. Activation of one of the pathways may antagonize or enhance the activation or effectiveness of another. The review will address these complexities and questions and propose directions of research which require high priority. Factors which encourage and suppress the application of ISR in agriculture will also be addressed.  相似文献   
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Thirty days before expected time of parturition, 20 Holstein cows were divided into ?Cr and +Cr groups. From day 25 before parturition (BP ) up to day 30 after parturition (AP ), +Cr cows received 10 mg of Cr (chromium‐enriched yeast) daily. Muscle and adipose tissue samples were taken at days ?30, ?10, +7 and +10 related to parturition, when body condition score (BCS ) was also determined. Hepatic tissue samples were taken at days ?10 and +7. Tissue samples were used for determination of the insulin signalling pathway protein expressions. Intravenous glucose tolerance test (IVGTT ) was performed at days ?28, ?7, +10 and +30. Milk yield was recorded during first 14 weeks AP . Milk composition was obtained at days 7 and 28 AP . At day 10 BP , protein content of β ‐subunit of insulin receptor (IR β ) was significantly higher (p ? 0.05) in muscle, and phosphorylation of insulin receptor substrate 1 at serine 307 (pIRS ‐1 Ser307) was significantly lower (p ? 0.05) in hepatic tissue of +Cr group. After parturition, pIRS ‐1 Ser307 was significantly lower in muscle tissue at days 7 and 28 (p ? 0.05 and p ? 0.001, respectively), while phosphorylation of Akt at serine 473 (pA kt Ser473) was significantly higher (p ? 0.01) in hepatic tissue at day 7 AP in +Cr group. Chromium had opposite effect on insulin kinetics during IVGTT s obtained BP and AP . Insulin secretion was significantly reduced at day 7 BP and significantly enhanced at day 10 AP , when NEFA concentration was also significantly increased. Milk yield and ECM value were depressed in +Cr group. DMI and BCS were significantly enhanced in +Cr group at day 7 BP . In conclusion, chromium modulates insulin signalling pathway in dairy cows, but targeted signalling molecules are different in antepartal then post‐partal period, probably due to duration of exposure to chromium and different energy status between those periods.  相似文献   
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107.
Transplantation of mussels to new aquaculture sites is currently being undertaken in Istria (Croatia) to increase production, minimize potential seasonal urban contamination, and secure safer seafood products. The purpose of this study was to determine the effects of season and transplantation on physiological indices (condition index and meat yield) of mussels, Mytilus galloprovincialis. Mussels were obtained from five aquaculture areas in Istria (central Lim Bay, Ra?a, Budava, Vabriga, and Pomer) and moved to a reference site in inner Lim Bay from April to July. Results showed that both season and transplantation affected physiological indices of mussels. Higher physiological indices were found in cultivated mussels from all areas in summer compared to spring, except in mussels from Vabriga and Pomer. In addition, higher physiological indices were found in mussels transplanted from central Lim Bay to the reference site in inner Lim Bay. Transplantation negatively affected physiological indices of mussels from Vabriga and Pomer, with no change in mussels from Ra?a and Budava. In conclusion, mussels from all areas exhibit satisfactory commercial results (≥15%) during the peak summer harvesting season. For most transplanted mussels, transplantation itself represents additional stress, bringing into focus adaptation processes, stock genetics, and favorable ecological conditions.  相似文献   
108.
Pulchellin E (1) and gaillardin (2) were isolated from the aerial parts of Inula oculus-christi, along with the flavone hispidulin. The 13C-NMR chemical shifts of 1 and 2 are reported.  相似文献   
109.
The treatment of seed potato tubers by imidacloprid, as well as the standard granular insecticides applied in the furrow, did not, in four years of trials, sufficiently prevent damage from wireworms, noctuid larvae and mole crickets to potato tubers. The main reason for this failure is the spatial and temporal distance between the application of insecticides and the moment when their action is needed. On the other hand, the effects of imidacloprid applied as seed tuber treatment on the larvae of the Colorado potato beetle was very good: depending upon conditions, it lasted from at least 55, to 70 days at the most. It protected the foliage from any substantial damage from the entire first generation, and ensured high yields. Therefore a decision on seed tuber treatment with imidacloprid in Croatia should primarily depend upon the cost/benefit calculation based on damage expected from the CPB (or aphids), and not from soil insect pests.  相似文献   
110.
Summary This report is dealing with the fumigation of grain in granaries with phosphine against the main stored-grain insects in Yugoslavia. The phosphine gas was generated from PHOSTOXIN tablets which were inserted in the grain mass. The efficacy was tested by the mortality of laboratory-bred insects and insects of the natural infestation. The successful fumigation was depending on the temperature of the grain and of the storage rooms and on the exposure period. The covering of the grain mass by plastic sheets reduced the gas leakage considerably. The dosage of 5–6 tablets per ton of grain and an exposure time of 5 days resulted in a 100% mortality of all insect stages at a grain temperature of 19° C. In all trials the exposure time proved to be the main factor. For the control of the angoumois grain moth and the Indian meal moth in the storage rooms outside the grain mass an additional treatment with an insecticidal spray was necessary. The control of hot spots by inserting the tablets through a probe was successful, provided that these hot spots were not too numerous and could be marked off very accurately.

Die Übersetzung aus dem Jugoslawischen besorgte Herr Dipl.-Ing. MAYR, die Bearbeitung des deutschen Textes erfolgte durch Herrn. Dr. F. NEUBECKER; beide Deutsche Gesellschaft für Schädlingsbekämpfung m. b. H., Frankfurt a. M.  相似文献   
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