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1.
Journal of Plant Diseases and Protection - This study explores the food plant spectrum of the sugar beet weevil (Asproparthenis punctiventris Germar; Coleoptera: Curculionidae), one of the most...  相似文献   
2.
Background: Nitrogen losses is an economic problem for wheat production and a high risk to the environment. Therefore, improved N fertilizer management is a key to increasing the N efficiency and minimizing N losses. To increase N efficiency, enhanced fertilizers such as urea combined with urease inhibitor can be used. Aims: The aim of present study was to evaluate the effects of different N forms on grain storage protein subunits in winter wheat and to examine whether the observed changes correlate with parameters of baking quality. Methods: The investigation was performed over two consecutive years at two locations in Germany. Protein subunits were analyzed by SDS‐PAGE. Results: Protein concentrations were similarly increased after fertilization with ammonium nitrate and urea + urease inhibitor. Analysis of the individual storage protein fractions indicated that both fertilizers specifically enhanced ω‐gliadins and HMW glutenins, but the effect was more pronounced in the ammonium nitrate treatment. Application of urea + urease inhibitor had greater influence on the protein composition and resulted in higher specific baking volume as well as the best fresh keeping ability, in comparison with urea treatment. Conclusion: Considering that the urea + urease inhibitor treatment resulted in almost comparable improvements of NUE and baking quality, with the additional benefit of reduced N losses in combination with easy handling, urea + urease inhibitor can be recommended as a viable alternative to both urea alone and ammonium nitrate treatments. This opens up an opportunity for the reduction of N loss in wheat production when use of urea is preferred.  相似文献   
3.
The aim of this study was to evaluate the interaction between yield levels of nonleguminous crops and soil organic matter (SOM) under the specific conditions of organic and conventional farming, respectively, and to identify implications for SOM management in arable farming considering the farming system (organic vs. conventional). For that purpose, correlations between yield levels of nonlegume crops and actual SOM level (Corg, Nt, Chwe, Nhwe) as well as SOM‐level development were examined including primary data from selected treatments of seven long‐term field experiments in Germany and Switzerland. Yield levels of nonlegume crops were positively correlated with SOM levels, but the correlation was significant only under conditions of organic farming, and not with conventional farming treatments. While absolute SOM levels had a positive impact on yield levels of nonlegumes, the yield levels of nonlegumes and SOM‐level development over time correlated negatively. Due to an increased demand of N from SOM mineralization, higher yield levels of nonlegumes obviously indicate an increased demand for OM supply to maintain SOM levels. Since this observation is highly significant for farming without mineral‐N fertilization but not for farming with such fertilization, we conclude that the demand of SOM‐level maintenance or enhancement and thus adequate SOM management is highly relevant for crop production in organic farming both from an agronomical and ecological point of view. Under conventional management, the agronomic relevance of SOM with regard to nutrient supply is much lower than under organic management. However, it has to be considered that we excluded other possible benefits of SOM in our survey that may be highly relevant for conventional farming as well.  相似文献   
4.
Development of common bean cultivars with partial white mould resistance through breeding techniques has been a challenge in Brazil. As yet, lines/cultivars from breeding programmes have not been investigated for resistance; therefore, this study screened 107 lines/cultivars for their reactions to white mould in 14 preliminary trials conducted under irrigation. Thirteen resistant lines/cultivars (three of Andean origin) and six Mesoamerican cultivars (three intermediately resistant and three susceptible) were selected for further investigation. These lines/cultivars and the resistant control A195 were evaluated in six advanced trials and two straw tests to assess the effectiveness of the screening procedure. In 11 preliminary trials, screenings were performed under moderate/high or higher disease pressure. These pressures occurred in two advanced trials in which, when yields were averaged across moderate/high and high pressures, 10 Mesoamerican lines/cultivars selected for resistance yielded 14%, 23%, and 38% more than intermediately resistant cultivars, A195, and susceptible cultivars, with median disease ratings (1–9 scale) of 4.5, 5.7, 5.7, and 6.7, respectively. In the straw test, three Andean lines/cultivars (A195 included) and two susceptible cultivars in the field were among those with the highest levels of physiological resistance. Thus, field rating under high disease pressure and greenhouse rating did not correlate significantly, suggesting that field trials are critical to evaluating resistance and to identifying high-yielding beans. Therefore, lines/cultivars from breeding programmes assessed in field trials may provide a low cost and fast way to identify high-yielding bean cultivars with partial resistance to white mould in the subtropical southern hemisphere.  相似文献   
5.
6.
A 5-year-old Holsteiner gelding from Germany was presented 2 months after a whitish discoloration of the left cornea was observed. Cytologic examination revealed intra- and extracellular globular structures, up to 4 micro m in size, consisting of a central spherical deeply basophilic body surrounded by an unstained halo. The structures were morphologically consistent with Histoplasma spp. Infection with Histoplasma organisms is not endemic in Europe. Topical use of fluconazole was successful in eliminating Histoplasma organisms within 10 days of initiation of treatment.  相似文献   
7.
Furosemide is a potent loop diuretic used for the prevention of exercise-induced pulmonary hemorrhage in horses. This drug may interfere with the detection of other substances by reducing urinary concentrations, so its use is strictly regulated. The regulation of furosemide in many racing jurisdictions is based on paired limits of urinary SG (<1.010) and serum furosemide concentrations (>100 ng/ml). To validate this regulatory mechanism, a liquid chromatography/mass spectrometry/mass spectrometry method employing a solid-phase extraction procedure and furosemide-d5 as an internal standard was developed. The method was used to determine the pharmacokinetic parameters of furosemide in equine serum samples and its effects on urinary SG after IV administration (250 mg) to 10 horses. Pharmacokinetic analysis showed that serum concentrations of furosemide were well described by a two-compartmental open model. Based on results in this study, it is very unlikely for horses to have serum furosemide concentrations greater than 100 ng/ml or urine SG less than 1.010 at 4 hours after administration (250 mg IV). However, it should be remembered that urine SG is a highly variable measurement in horses, and even without furosemide administration, some horses might naturally have urine SG values less than 1.010.  相似文献   
8.
OBJECTIVE: To compare serum concentrations of 1,25-dihydroxycholecalciferol (1,25-[OH]2D3) and 25-hydroxycholecalciferol (25-[OH]D3) in healthy control dogs and dogs with naturally occurring acute renal failure (ARF) and chronic renal failure (CRF). ANIMALS: 24 control dogs, 10 dogs with ARF, and 40 dogs with CRF. PROCEDURE: Serum concentrations of 1,25-(OH)2D3 were measured by use of a quantitative radioimmunoassay, and serum concentrations of 25-(OH)D3 were measured by use of a protein-binding assay. RESULTS: Mean +/- SD serum concentration of 1,25-(OH)2D3 was 153 +/- 50 pmol/L in control dogs, 75 +/- 25 pmol/L in dogs with ARF, and 93 +/- 67 pmol/L in dogs with CRF. The concentration of 1,25-(OH)2D3 did not differ significantly between dogs with ARF and those with CRF and was in the reference range in most dogs; however, the concentration was significantly lower in dogs with ARF or CRF, compared with the concentration in control dogs. Mean +/- SD concentration of 25-(OH)D3 was 267 +/- 97 nmol/L in control dogs, 130 +/- 82 nmol/L in dogs with ARF, and 84 +/- 60 nmol/L in dogs with CRF. The concentration of 25-(OH)D3 was significantly lower in dogs with ARF or CRF, compared with the concentration in control dogs. CONCLUSIONS AND CLINICAL RELEVANCE: The concentration of 1,25-(OH)2D3 was within the reference range in most dogs with renal failure. Increased serum concentrations of parathyroid hormone indicated a relative deficiency of 1,25-(OH)2D3. A decrease in the serum concentration of 25-(OH)D3 in dogs with CRF appeared to be attributable to reduced intake and increased urinary loss.  相似文献   
9.
Lidocaine is a local anaesthetic agent that is widely used in equine medicine. It is also an Association of Racing Commissioners International (ARCI) Class 2 foreign substance that may cause regulators to impose substantial penalties if residues are identified in post race urine samples. Therefore, an analytical/pharmacological database was developed for this drug. Using our abaxial sesamoid local anaesthetic model, the highest no-effect dose (HNED) for the local anaesthetic effect of lidocaine was determined to be 4 mg. Using enzyme-linked immunosorbent assay (ELISA) screening, administration of the HNED of lidocaine to eight horses yielded peak serum and urine concentrations of apparent lidocaine of 0.84 ng/mL at 30 min and 72.8 ng/mL at 60 min after injection, respectively. These concentrations of apparent lidocaine are readily detectable by routine ELISA screening tests (LIDOCAINE ELISA, Neogen, Lexington, KY). ELISA screening does not specifically identify lidocaine or its metabolites, which include 3-hydroxylidocaine, dimethylaniline, 4-hydroxydimethylaniline, monoethylglycinexylidine, 3-hydroxymonoethylglycinexylidine, and glycinexylidine. As 3-hydroxylidocaine is the major metabolite recovered from equine urine, it was synthesized, purified and characterized, and a quantitative mass spectrometric method was developed for 3-hydroxylidocaine as recovered from horse urine. Following subcutaneous (s.c.) injection of the HNED of lidocaine, the concentration of 3-hydroxylidocaine recovered from urine reached a peak of about 315 ng/mL at 1 h after administration. The mean pH of the 1 h post dosing urine samples was 7.7, and there was no apparent effect of pH on the amount of 3-hydroxylidocaine recovered. Within the context of these experiments, the data suggests that recovery of less than 315 ng/mL of 3-hydroxylidocaine from a post race urine sample is unlikely to be associated with a recent local anaesthetic effect of lidocaine. Therefore these data may be of assistance to industry professionals in evaluating the significance of small concentrations of lidocaine or its metabolites in postrace urine samples. It should be noted that the quantitative data are based on analytical methods developed specifically for this study, and that methods used by other laboratories may yield different recoveries of urine 3-hydroxylidocaine.  相似文献   
10.
Classification of thermally modified wood by FT-NIR spectroscopy and SIMCA   总被引:1,自引:0,他引:1  
Quality assessment of thermally modified wood has evolved as one of the major fields in the research on thermal modification of wood. This study investigates NIR spectroscopy in combination with the pattern recognition method of soft independent modeling of class analogies (SIMCA). Focus is put on identifying different treatment intensities of thermally modified samples of beech, ash, and Norway spruce. The results indicate that SIMCA classification based on NIR spectroscopy could be used for quality control of thermally modified wood. The method might be applicable for producers (pre-delivery checks) and customers (reception control). However, transfer from laboratory to industrial conditions needs further investigation.  相似文献   
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