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1.
Variety-specific reaction of Lolium perenne L. on selective systemic herbicides
The investigation intended to show the specific reaction of different varieties of Lolium perenne on selective systemic herbicides. These results can be regarded as the base for advanced explorations to the described topic. The results may be summarized as follows:
Independent of the stage of growth, the date of application, the dosage and the droplet size there were effects on the forage yield in correlation to the variety and the active ingredient. Measurable yield reductions were presented after CMPP application on the varieties of the late and after the treatment with Asulam on the varieties of the early maturity group. Compared to the maturity group the varietal attribute growthhabit demonstrated no significant effects. The active ingredients MCPB and MCPA presented not any measurable influence on the forage yield of the different varieties. In the main harvest year the yield depressions were manifested clearer than in the seeding year. In the same way the described secondary actions were larger after the treatment in an advanced stage.
Extended investigations should inquire to the causes and secondary effects on the forage quality. Beyond this for variety testings of species with a large distribution and volume it seems remunerative to include questions of herbicides tolerance.  相似文献   
2.
The features of severe ischemic brain damage after strangulation by the owner of a 1-year-old German shepherd dog are described. The dog was disciplined by the owner during training by holding the dog off the ground by his choke chain collar. At first, the dog behaved normally, but he became increasingly ataxic and started circling to the left and showed reduced consciousness. The neurological examination revealed severe disorientation, left lateral pleurothotonus, and circling. The neurological findings were consistent with a multifocal brain lesion. A magnetic resonance imaging scan was performed and showed changes in the T2- and diffusion-weighted images, consistent with severe cerebral edema resulting from ischemia. Because of the severity of the clinical features, the dog was later euthanized. To the author's knowledge, this is the first report of a severe brain ischemia after strangulation in a dog.  相似文献   
3.
For the selection of donors with valuable characteristics for breeding, 39 thyme accessions were evaluated in three years according to a staggered schedule. The criteria investigated were: winter hardiness, beginning of flowering, growth height, yield of the dry herb, content of essential oil, composition of the essential oil, DNA content of cell nuclei and number of chromosomes. The most strongly varying traits between the populations were the yield of dry herb, the content of essential oil and the content of volatile phenols with coefficients of variation (CV) between CV 40% and 50%. The largest variation within a population was detected for the yield of dry herb (CV 25–46%) and the content of essential oil (CV 17–48%). The homogeneity of the populations was different. The minimal average coefficient of variation of all traits (CV 19%) was determined in the population of the cultivar ‘Varico II’ and in a population from Lithuania. The ploidy level of T. vulgaris was diploid (2n = 30).  相似文献   
4.
Effect of juice extractor settings on juice cloud stability.   总被引:2,自引:0,他引:2  
Juice was extracted from Valencia oranges using three different extractor settings. Differential juice cloud stability was observed. Soft-extracted juice was the most stable, and hard-extracted juice was the least stable. The medium-extracted juice had intermediate cloud stability. Yearly (1997 versus 1998) differences were observed, but the relationship among the juices did not change. Addition of protein extracts, obtained from each juice, to pasteurized juice also resulted in differential cloud stability. Using pectinmethylesterase (PME) activity estimated at pH 4.5, the effects of the protein extract mirrored results from raw juice. Estimating PME activity at pH 7.5 produced contradictory results, indicating that predicting consequences of PME activity estimated at pH 7.5 is unreliable.  相似文献   
5.
In addition to the main flavanone glycosides (i.e., hesperidin and naringin) in citrus peel, polymethoxylated flavones and numerous hydroxycinnamates also occur and are major phenolic constituents of the molasses byproduct generated from fruit processing. Although a small number of the hydroxycinnamates in citrus occur as amides, most occur as esters and are susceptible to alkaline hydrolysis. This susceptibility to alkaline hydrolysis was used in measuring the concentrations of hydroxycinnamates in citrus peel molasses. The highest concentrations of hydroxycinnamates occurred in molasses of orange [C. sinensis (L.) Osbeck] and tangerine (C. reticulata Blanco.) compared to grapefruit (C. paradisi Macf.) and lemon [C. limon (L.) Burm.]. Concentrations of two phenolic glucosides, phlorin (phloroglucinol-beta-O-glucoside) and coniferin (coniferyl alcohol-4-beta-O-glucoside), were also measured. Measurements of the polymethoxylated flavones in molasses from several tangerine and orange varieties showed that these compounds occurred in the highest amounts in Dancy tangerine, whereas samples from two other tangerine molasses contained significantly lower levels, similar to those in the molasses samples from late- and early/mid-season oranges.  相似文献   
6.
Immunoblotting assays using commercial antibodies were established to investigate the unexpected persistence of the immunoactive Cry1Ab protein in the bovine gastrointestinal tract (GIT) previously suggested by enzyme-linked immunosorbent assay (ELISA). Samples of two different feeding experiments in cattle were analyzed with both ELISA and immunoblotting methods. Whereas results obtained by ELISA suggested that the concentration of the Cry1Ab protein increased during the GIT passage, the immunoblotting assays revealed a significant degradation of the protein in the bovine GIT. Samples showing a positive signal in the ELISA consisted of fragmented Cry1Ab protein of approximately 17 and 34 kDa size. Two independent sets of gastrointestinal samples revealed the apparent discrepancy between the results obtained by ELISA and immunoblotting, suggesting that the antibody used in the ELISA reacts with fragmented yet immunoactive epitopes of the Cry1Ab protein. It was concluded that Cry1Ab protein is degraded during digestion in cattle. To avoid misinterpretation, samples tested positive for Cry1Ab protein by ELISA should be reassessed by another technique.  相似文献   
7.
The present study was conducted to study the impact of the virulence factors invC and sseD of the two type III secretion systems of Salmonella enterica serovar Typhimurium (S. Typhimurium) on the pathogenesis of the porcine S. Typhimurium DT104 infection. For this purpose, two S. Typhimurium mutant strains with a disrupted invC gene of the Salmonella pathogenicity island 1 or with a disrupted sseD gene of the Salmonella pathogenicity island 2 have been studied in experimental infection of pigs. Twenty-two 7-week-old male hybrid pigs were either infected with one of the mutants or the wild-type S. Typhimurium DT104 strain. Each group was examined for clinical signs, Salmonella shedding rate and the specific antibody response. Survival and replication were evaluated by qualitative and quantitative determination of the colonization rate. The humoral and cellular immune responses were examined using isotype-specific ELISA and quantitative real-time PCR of IL-2, IL-4, IL-10, IL-12 and IFN-gamma. The results proved that both mutants had a lower virulence (with marked differences between both mutants) than the wild-type and that both virulence factors have importance in porcine salmonellosis. Only pigs infected with the wild-type S. Typhimurium DT104 exhibited typical clinical symptoms of salmonellosis like anorexia, vomiting, disturbed demeanour, fever and diarrhoea. Deletion of the invC gene resulted in a significantly reduced colonization rate. Interestingly, the mRNA expression of both type-1 and type-2 cytokines were significantly decreased in pigs infected with either the invC-mutant and the sseD-mutant strain.  相似文献   
8.
The estimation model PhytoCalc allows a non-destructive quantification of dry weight and nutrient pools of understorey plants in forests by using the relationship between species biomass, cover and mean shoot length. The model has been validated with independent samples in several German forest types and can be a useful tool in forest monitoring. However, in open areas within forests (e.g. clearcuts), the current model version underestimates biomass and produces unreliable nutrient pool estimations. Thus, tissue density, as approximated by leaf dry matter content (LDMC), is systematically higher under high light compared to low light conditions. We demonstrate that the ratio of LDMC under clearcut conditions to LDMC under forest conditions can be used to adjust the PhytoCalc model to clearcut conditions. We investigated the LDMC ratio of five exemplary species commonly occurring on clearcuts. Integrating the square of the ratio as a correction factor improved estimates of biomass to more than 70% fit between observations and predictions. Results also suggest this ratio can be used to correct nutrient concentrations modelled in PhytoCalc, which tend to be overestimated in clearcuts. As morphological groups of plant species exhibit significantly different ratios, we advise using group-specific correction factors for clearcut adjustments in the future.  相似文献   
9.
Insect resistant Bt 176 maize has been developed by genetic modification to resist European borer infection. In the present investigation, the experiment was conducted to determine the effect of feeding a new hybrid of Bt 176 maize (NX 6262- Bt 176) on general health condition and performance of broiler chickens. Maize grains and diets were subjected to proximate analysis. Amino and fatty acids investigation were applied for both maize grains before used. To evaluate the degradation of NX 6262- Bt 176 maize DNA and its metabolic fate in broiler blood, muscles and organs. One-day-old male broilers were fed ad libitum on either an experimental diet containing NX 6262- Bt 176 or a control diet containing the non-modified maize grains for 35 days. Feed consumption and body weight were recorded weekly during the experimental period. All chickens were subjected to nutritional evaluation period at day 20 of age for 5 successive days, to calculate the percentage of apparent digestible nutrients in both diets. At day 35 samples were collected at several intervals after feed withdrawal. Prior to slaughter blood samples were collected from all birds by heart puncture to prevent DNA cross contamination. Samples from pectoral and thigh muscles, liver, spleen, kidney, heart muscle, bursa and thymus glands were collected. Digesta from different sections of the gastrointestinal tract (GIT) were collected as well. Packed cell volume (PCV) and some serum parameters were investigated. There were no significant differences between control and experimental group concerning chemical composition of feeds, apparent digestible nutrients, and all performance parameters measured (P > 0.05). Furthermore, there were no differences in the PCV and the analysed serum parameters between the control and experimental group. The results of maize DNA digestibility showed that the new variety takes the normal physiological passage along broiler GIT similar to the conventional line. In addition, Bt 176 maize DNA appears to be partially degraded in different parts of GIT comparable to the DNA of the control maize line. Results of the metabolic fate of maize DNA in broiler blood, muscles and organs indicated that only short DNA fragments (199 bp) derived from the plant chloroplast gene could be detected in the blood, skeletal muscles, liver, spleen and kidney, which disappeared after prolongation the fasting time. In heart muscle, bursa of Fabricius and thymus, no plant chloroplast DNA was found. Bt gene specific constructs from Bt 176 maize were not detected in any investigated blood or tissue samples.  相似文献   
10.
Coatings of biomaterials or implants that facilitate biomineralization possess a great potential for applications focused to the replacement, augmentation, and regeneration of bone tissue. Biomimetic approaches utilize biomolecules for either templating or supporting the crystallization process. One of these promising biomolecules is phosvitin (PV), an egg yolk protein known to transport and store inorganic phosphates and calcium ions. The incorporation of PV into polyelectrolyte multilayers is favorable due to PVs high degree of phosphorylation and thus a high acidity. Utilizing the reflectometric interference spectroscopy, the adsorption kinetics of this novel polyelectrolyte system composed of poly-L-lysine and the heavily phosphorylated phosvitin were monitored. The results demonstrate an unexpected nonregular growth regime called overshoot. Effective measures of shifting this irregular polyelectrolyte adsorption process back to a regular multilayer growth regime are reported in this paper.  相似文献   
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