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81.
Lutz-Wohlgroth L Becker A Brugnera E Huat ZL Zimmermann D Grimm F Haessig M Greub G Kaps S Spiess B Pospischil A Vaughan L 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2006,53(4):185-193
The aim was to detect and characterize chlamydial infections in guinea-pigs (GP) with ocular disease, study their pathogenicity and zoonotic potential and to test for the presence of Acanthamoebae spp. in GP eyes and to investigate whether they could act as vectors for Chlamydia-like organisms. Overall 126 GP, of which 77 were symptomatic, were screened by clinical examination, cytology, gross pathology, histology, immunohistochemistry, polymerase chain reaction (PCR) and bacteriology. A new Chlamydiaceae-specific intergenic spacer rRNA gene PCR, designed to amplify this segment linking the 16S and 23S regions, was performed. DNA samples were also received from one owner including samples of his cat and rabbit. Guinea-pigs: 48 of 75 symptomatic, but only 11 of 48 asymptomatic GP were positive by PCR for Chlamydophila caviae guinea-pig inclusion conjunctivitis (GPIC) (P < 0.0001). Eighteen of 75 or 15/48, respectively, were positive for DNA from Chlamydia-like organisms. Acanthamoebae-DNA could be found in two GP, of which one was symptomatic. Owner, cat and rabbit: Samples of all three species were positive by PCR for C. caviae GPIC and the owner's one-day disposable contact lenses showed a positive PCR result for the Chlamydia-like organism Parachlamydia acanthamoebae. No Acanthamoebae-DNA could be detected. This study is the first to describe Chlamydia-like organisms in GP and to detect C. caviae GPIC in human, cat and rabbit. Therefore, C. caviae GPIC could pose a zoonotic potential. We believe that the finding of C. caviae GPIC in species other than GP is probably not unique. 相似文献
82.
83.
Gunnar Morozov Jürgen Aosaar Mats Varik Hardo Becker Krista Lõhmus Allar Padari 《Scandinavian Journal of Forest Research》2019,34(1):12-25
The decomposition of the leaf litter, fine roots (d?<?2?mm) and coarser roots (2?≤?d?<?5?mm) of grey alder and silver birch, as well as of α-cellulose sheets using the litterbag method was studied in two experimental stands on Podzoluvisol soils in Southern Estonia. For both tree species, the coarser roots decomposed faster than the fine roots, (p?<?.05), tree species did not affect the decomposition rate of the roots (p?>?.5). The nitrogen (N) input to soil from aboveground litter was multiple times higher than the N flux from roots. The remaining relative ash-free mass of the leaves of grey alder and silver birch after three and a half years was similar. After 11 years the remaining relative ash-free mass of the fine and coarser roots of grey alder still accounted for around 10% of the initial value. For silver birch the remaining value was around 20% after 9 years. The litterbag method to underestimates in fertile soils the decomposition of organic matter and thus did not reflect the actual dynamics of decomposition. 相似文献
84.
Muluneh Tamiru Heiko C. Becker Brigitte L. Maass 《Genetic Resources and Crop Evolution》2008,55(1):115-131
Yam (Dioscorea spp.) is widely grown in many parts of Ethiopia and plays a vital role in local subsistence. Nevertheless, its diversity
has not been studied in detail. A survey covering 339 farm households and eight districts was conducted in the major yam growing
regions of Southern Ethiopia to investigate the diversity and distribution of yam landraces using structured and semi-structured
questionnaires. A total of 37 named landraces were recorded, with a range from one to six (mean 2.9) on individual farms.
Farmers’ decisions regarding the number and type of landraces maintained was influenced by tolerance of the landraces to drought,
their maturity time and market demand. Most landraces had limited abundance and distribution, and only a few dominant landraces
were widely grown. There was also variation amongst districts with respect to diversity, distribution and abundance of the
landraces found. In the majority of the localities surveyed, farmers reported a decreasing trend in the number of landraces
maintained on individual farms and in the overall yam production. Besides, in those limited areas where yam production is
expanding, farmers are increasingly relying on a few selected landraces that mature early. Findings of this study suggest
that local farmers in Wolayita and Gamo-Gofa zones maintain considerable yam diversity that remains to be further explored
for sustainable utilization and conservation of the available genetic resources. 相似文献
85.
86.
Liza Wittenberg-Voges Sabine BR. Kästner Marja Raekallio Outi M. Vainio Karl Rohn Klaus Hopster 《Veterinary anaesthesia and analgesia》2018,45(2):165-174
Objective
To compare the effects of MK-467 during isoflurane anaesthesia combined with xylazine or dexmedetomidine on global and gastrointestinal perfusion parameters.Study design
Prospective, randomized experimental trial.Animals
A total of 15 warmblood horses.Methods
Horses were divided into two groups for administration of either dexmedetomidine (D) or xylazine (X) for premedication (D: 3.5 μg kg?1; X: 0.5 mg kg?1) and as constant rate infusion during isoflurane anaesthesia (D: 7 μg kg?1 hour?1; X: 1 mg kg?1 hour?1). During anaesthesia, heart rate, mean arterial blood pressure (MAP), systemic vascular resistance index (SVRI) and cardiac index (CI) were measured. Microperfusion of the colon, jejunum and stomach was measured using laser Doppler flowmetry. After 2 hours of stabilization, MK-467 (250 μg kg?1) was administered, and measurements were continued for another 90 minutes. For statistical analysis, the permutation test and Wilcoxon rank-sum test were used (p < 0.05).Results
There were no differences in baseline measurements between groups. The MK-467 bolus resulted in a significant decrease in MAP (D: –58%; X: –48%) and SVRI (D: –68%; X: –65%) lasting longer in group D (90 minutes) compared to group X (60 minutes). While CI increased (D: +31%; X: +35%), microperfusion was reduced in the colon (D: –44%; X: –34%), jejunum (D: –26%; X: –33%) and stomach (D: –37%; X: –35%).Conclusions and clinical relevance
Alpha-2-agonist induced vasoconstriction was reversed by the MK-467 dose used, resulting in hypotension and rise in CI. Gastrointestinal microperfusion decreased, probably as a result of insufficient perfusion pressure. An infusion rate for MK-467 as well as an ideal agonist/antagonist ratio should be determined. 相似文献87.
Objective
To evaluate the transdermal local anaesthetic effect of lidocaine or lidocaine combined with prilocaine or tetracaine in horses.Study design
Experimental, randomized study.Animals
A total of five healthy adult warmblood horses.Methods
Horses were clipped bilaterally at the withers, cranial saddle area and caudal saddle area. Baseline measurements for mechanical superficial sensation via von Frey filaments and nociceptive thermal thresholds were performed. A 5% lidocaine patch (12 hour exposure, treatment L), a lidocaine/prilocaine cream (each 2.5%, treatment LP) and a lidocaine/tetracaine cream (each 7%, treatment LT) were applied (both 2 hour exposure). The same product was applied at the same location bilaterally, but on the right side an epidermal micro-perforation (dermaroller, 1200 needles) was performed prior to application. A total of five more measurements were performed at each location, immediately at the end of exposure time followed by hourly measurements. Thermal thresholds normalized to thermal excursion were analysed. One- or two-way anova and the Wilcoxon signed-rank test were used for statistical analysis with p < 0.05 considered significant.Results
Epidermal micro-perforation had no enhancing effect. Treatments L, LP, and LT resulted in increased thermal excursion (%) immediately (84.7 ± 12.9; 100.0 ± 0.0; 100.0 ± 0.0) and 1 hour (81.7 ± 66; 86.0 ± 17.7; 87.7 ± 14.4) after the removal of the respective product compared to baseline (66.1 ± 9.3; 69.9 ± 8.3; 76.5 ± 7.8). Superficial mechanical sensation was decreased by the lidocaine-and-tetracaine cream at all time points, and by the lidocaine patch and lidocaine-and-prilocaine cream for three measurements.Conclusions and clinical relevance
Eutectic mixtures of lidocaine with either prilocaine or tetracaine led to a reduction in thermal nociception and mechanical sensation for up to 2 hours. 相似文献88.
Molecular wheat breeding by direct gene transfer 总被引:7,自引:0,他引:7
A method for efficient genetic transformation of wheat has been developed using immature embryos as targets for microprojectile-mediated
gene transfer and a helium driven particle delivery system. Screening and selection of transgenic cells, somatic embryos and
regenerated plants are performed with the gus-gene and the phosphinothricin acetyl transferase (bar) gene coding for Basta-resistance
as the selectable marker. On average, one fertile transgenic plant can be obtained from about 100 microprojectile treated,
immature embryos. The number of integrated copies of the transferred gene ranges from 1 up to about 10. Stable integrated
genes are inherited in most of the transgenic lines in a normal mendelian fashion segregating 3:1 in the F2. Homozygous, as well as heterozygous, lines have been followed and analysed genetically at the molecular level and up to
F5. Apart from normal stable gene expression, examples have also been found which showed a loss of gene activity or unexpected
segregation pattern. For applied aspects, different genes are transferred aiming for improved disease resistance, modification
of quality, or other characteristics. First results from these transgenic lines are reported, and problems still existing
with the production of stable transgenic wheat lines are discussed.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
89.
E. Umapathy K. H. Erlwanger H. P. S. Makkar K. Becker S. G. Pierzynowski 《Journal of animal physiology and animal nutrition》1999,82(2-3):57-65
Introduction Cowpea (Vigna unguiculata) is a valuable protein source that can contribute towards overcoming a predicted protein deficit equivalent to more than 1 000 000 t oilcake in Southern Africa by the year 2000 (N ell et al. 1992). However, like most other legumes, cowpeas contain antinutritional factors (ANFs) (M akinde et al. 1996). It has also been shown that feeding raw cowpea causes reduced growth and histomorphometric changes in the various segments of the intestine (M akinde et al. 1997) attributable to ANFs. The major ANFs in the cowpea are trypsin inhibitors, tannins and phytates (A letor and A ladetimi 1989). Although the protease inhibitors are found in most legumes, only soybean inhibitors have been thoroughly investigated (L iener and K akade 1980), and trypsin inhibitors in other legumes have received little attention. 相似文献
90.
甘蓝型油菜(Brassica napus)无花瓣突变体“ Ap-Tengbe ”花瓣性状的遗传规律 总被引:2,自引:0,他引:2
本项研究旨在探明甘蓝型油菜突变体Ap-Tengbe无花瓣性状的遗传规律,‘Ap-Tengbe’和德国栽培品种‘Falcon’之间通过正反交产生两个方向的F1,BC1-1(F1和‘Ap-Tengebe’之间),BC1-2(F1和‘Falcon’之间)以及F2各遗传群体,根据田间各遗传群体PDgr(花瓣度)的观察和统计,作者提出‘Ap-Tenge’突变体无花瓣性状的遗传由细胞质和两对核隐性基因共同控制 相似文献