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41.
Fourier transform (FT)-Raman spectroscopy was applied to the analysis of genetically modified (GM) plant tissue. Transgenic carrot callus and tobacco plants possessing a novel StSn1 gene coding for a cysteine-rich snakin-1 polypeptide were obtained after Agrobacterium-mediated transformation. The presence of the StSn1 gene and its expression were confirmed by polymerase chain reactions using plant DNA and cDNA as templates for the amplification of the transgenes. Raman measurements were taken from lyophilized GM carrot callus tissue, fresh GM tobacco leaves, and from seeds produced by GM tobacco plants as well as from the nontransformed controls. Cluster analysis applied to the obtained spectra allowed clear separation of the GM samples expressing the StSn1 gene and the nontransformed control to distinct groups. Such discrimination was achieved only when wavenumber ranges around 500 cm (-1) were analyzed. The results indicate that discrimination between the GM and non-GM materials was related to S-S stretching vibrations in snakin-1, as it contained six sulfur bridges. Other introduced genes, neomycine phosphotransferase ( nptII) and Chitinase ( chit36), did not cause any detectable changes by Raman spectroscopy in plant tissue. This is the first report on the use of Raman spectroscopy for a nondestructive analysis of GM plant material expressing the gene coding for a cysteine-rich polypeptide.  相似文献   
42.
Leptosphaeria maculans, the ascomycete fungus which causes blackleg disease of oilseed rape, has been considered for a long time as a single species divided into aggressive and non-aggressive pathogenicity groups which differ in their economic importance. However, the development of accurate biochemical and molecular characterisation methods has demonstrated that the world-wide L. maculans population actually comprises at least two species. The aim of this research was to assess the ability of rep (repetitive element based)-PCR genomic fingerprinting methods, initially developed for bacterial identification, to characterise a collection of 90 isolates of L. maculans from Poland, in comparison with reference isolates from the IBCN (International Blackleg of Crucifers Network) collection. REP (repetitive extragenic palindromic)-, ERIC (enterobacterial repetitive intergenic consensus)-, and BOX primers for rep-PCR genomic fingerprinting, and primers derived from LMR1, a L. maculans specific repeated element, were tested. Rep-PCR and LMR1-based analyses were able to discriminate the different components of the species complex and to evaluate the genetic diversity within each member of the complex. These analyses suggested that Polish populations of L. maculans mainly belong to the non-aggressive species, rather than the aggressive species which is prevalent in Western Europe, Canada and Australia.  相似文献   
43.
A hitherto unknown parasite of theResseliella piceae larvae, the pest of fir-seeds (Abies alba Mill.), was found and identified asInostemma melicerta. The material originated from the Piwniczna Management Unit in Beskid S?decki Mts. in southern Poland.  相似文献   
44.
OBJECTIVE: To identify radiographic abnormalities associated with degenerative lumbosacral stenosis (DLSS) in German Shepherd Dogs (GSDs) and determine whether specific radiographic abnormalities could be used to identify dogs at risk of developing DLSS. DESIGN: Cohort study. ANIMALS: 33 GSDs working as police dogs. PROCEDURES: Results of physical, neurologic, and orthopedic examinations were used to identify dogs with DLSS. Survey radiography of the lumbosacral junction was performed, and radiographs were compared with radiographs obtained 3 years earlier. RESULTS: DLSS was diagnosed in 15 of the 33 (45%) dogs. Thirteen of the 15 dogs with DLSS and 14 of the 18 dogs without DLSS had radiographic abnormalities of the lumbosacral junction. Twenty-two (67%) dogs were able to perform unrestricted duties, including 3 dogs with suspected DLSS. Six (18%) dogs had been excluded from active duty during the period of surveillance because of DLSS. Significant progression in specific clinical and radiographic signs was detected, but multiple logistic regression analysis did not identify any radiographic signs that could be used to predict the development of DLSS. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that survey radiography cannot be used to predict development of DLSS in working GSDs.  相似文献   
45.
OBJECTIVE: To investigate subjective and computerized methods of evaluation of color Doppler (CD) and power Doppler (PD) ultrasonographic images (obtained before and after administration of contrast medium) for quantitative assessment of vascularity and perfusion of various naturally occurring tumors in dogs. SAMPLE POPULATION: 34 tumors in 34 dogs. PROCEDURE: Tumors in dogs were examined via CD and PD ultrasonography before and after i.v. injection of a microbubble contrast agent (pre- and postcontrast examinations, respectively). Images were digitized for subjective assessment of vessel density and vascular pattern and computer-aided assessment of parameters of vascularity (fractional area [FA]) and perfusion (color-weighted FA [CWFA] and mean color-weighted FA [CWFA] and mean color level). RESULTS: With both analysis methods, more vessels were identified in precontrast PD ultrasonographic images than in precontrast CD ultrasonographic images. Moreover, compared with values for precontrast PD ultrasonography, FA, CWFA, and mean color level were higher for postcontrast PD ultrasonography. In postcontrast images, there was a significant association between vessel densities determined through subjective and computerized assessments. Although sample size was small, vascularity of squamous cell carcinomas was significantly greater than that of other tumor types. Ten of the 19 softer than issue that sarcomas had low vessel density with minor contrast enhancement. With increasing gross tumor volume, FA and CWFA decreased for all Doppler ultrasonographic methods. CONCLUSIONS AND CLINICAL RELEVANCE: Higher values of the ultrasonographic parameters representing vascularity and perfusion of tumors in dogs were determined via PD ultrasonography after administration of contrast medium than via PD or CD ultrasonography without administration of contrast medium.  相似文献   
46.
Locoregional lymph nodes are routinely examined in order to define the spatial extent of neoplastic disease. As draining patterns of certain tumor types can be divergent from expected anatomical distribution, it is critical to sample the lymph nodes truly representing the draining area. The aim of this bicenter prospective pilot study was to describe the technique of computed tomographic (CT)‐lymphography for primary draining lymph node mapping in tumor staging in dogs. Forty‐five dogs with macro‐ or microscopic tumors in specified localizations were evaluated. Depending on body weight, 0.8–2 ml contrast agent (iohexol) was injected into four quadrants around the tumor, and CT‐images were obtained at 1, 3, 6, 9, and 12 minutes post‐injection. Attenuation of chosen regions of interest (Hounsfield units (HU)) and patterns of enhancement were assessed for 284 lymph nodes in the precontrast study with median HUs of 31.1 (Interquartile range (IQR) = 18.4) and for 275 in the intravenous postcontrast study with 104.3 HU (IQR = 31.2) (paired Wilcoxon test, P < 0.001). In the CT‐lymphography study, 45 primary draining lymph nodes with a significantly higher median HU value of 348.5 (IQR = 591.4) (one‐sample t‐test, P < 0.001) were identified. Primary draining lymph nodes were found to be clearly visible after 1–3 minutes after local injection, often concurrent with a good visibility of the lymphatic vessel system. The herein described technique of peritumorally injected CT‐contrast agent followed by subsequent CT‐lymphography for primary draining lymph node mapping works well in a majority of cases in all investigated sites and warrants further validation for different tumor entities.  相似文献   
47.
Leisure riding is a popular way of using horses however, unlike sport or racing horses, those are mostly not associated with one rider with high skills. Constant overload of equine musculoskeletal system causes pathologies, which are affecting horse mobility and decreases the horse‐rider communication. The aim was to propose the new scoring system of thermograph analysis as an aspect of differences in heat distributions on horseback before and after leisure ridings. The study was conducted on sixteen Polish warmblood horses, scanned with a non‐contact thermographic camera. Heat pattern of the thoracolumbar area was evaluated on thermograms taken before and after exercise. The criteria with point values for horse‐rider‐matching were created: heat points on the dorsal midline of saddle‐back contact area and degree of muscle unit overload. The results of thermograph analysis were compared with the results of a questionnaire on horse‐rider communication during riding in order to estimate the relevance of matching. The maximum score was obtained in 38.3% and 39.8% of combinations based on the thermograph analysis and questionnaire, respectively. Results of both scoring systems were strongly positive correlated (r = .937), demonstrating high sensitivity (61.72%) and specificity (90.23%) of the matching. The horse‐rider matching may improve horse comfort during leisure type of work.  相似文献   
48.
摘要:油菜菌核病是由Sclerotinia sclerotiorum (Lib) de Bary引起的,是世界范围内造成损失最严重的病害之一。该病害主要通过感染了核盘菌子囊孢子的花瓣落在植株茎、叶上来侵染植株。本实验采用添加了两种不同PH指示剂的改良型Steadman’s培养基检测被子囊孢子感染的花瓣,样品采自合肥的两块不同试验田,在油菜花期(3月下旬~4月中旬)每天采摘新鲜花瓣在室温下培养,结果表明整个花期,除1块田1天没有检测出外,其余每天都有被子囊孢子感染的花瓣出现(感染子囊孢子的花瓣接种后培养基变色)。油菜初花期被子囊孢子感染的花瓣较少,而盛花期和终花期被感染的花瓣较多,第一块田被感染的花瓣数在两种培养基上出现的百分率分别为32.0%和40.2%,第二块田分别为27.3%和35.7%。第一块田油菜菌核病的发病率和病指分别为2.7%和1.8,第二块田分别为1.5%和0.4。子囊孢子感染的花瓣数与后期油菜菌核病的发病率呈显著正相关(r=0.829,r0.05=0.811)。研究被感染的花瓣数可以帮助决定最适宜的病害防治时期。  相似文献   
49.
Lupin seed globulin proteins form complexes with flavonoids, predominantly apigenin C-glycosides. Enzymes typical for the gastrointestinal tract were used to hydrolyze lupin seed globulins. Release of native flavonoids as a result of the proteolysis reaction was observed. Different analytical methods such as size exclusion chromatography, HPLC-MS, and fluorescence spectroscopy (steady-state fluorescence, fluorescence anisotropy, fluorescence lifetimes) were used for a detailed characterization of this phenomenon. Flavonoids liberated from lupin globulin proteins as a result of pancreatin-catalyzed digestion were bound by γ-conglutin resistant to this enzyme. Two possible mechanisms of this interaction may be suggested: hydrogen bonding between oligosaccharide chains of glycoproteins and the sugar moieties of the flavonoid glycosides or electrostatic attraction between positively charged γ-conglutin and flavonoids partially ionized at pH 7.5.  相似文献   
50.
The water-extractable arabinoxylans (WE AXs) present in rye bread govern its viscous properties, which may be related to reduced risk of cardiovascular diseases and diabetes. Breads made from rye cultivars generally exhibit higher AX-dependent extract viscosities (Cyran, M. R.; Saulnier, L. Food Chemistry2012, 131, 667-676) when compared with those produced from inbred lines used for their breeding. To give further details about this trend, the WE AXs were isolated from breads of lines and structurally characterized by HPSEC and (1)H NMR spectroscopy. The extract viscosities of endosperm and whole-meal breads were usually comparable, in contrast to those made from rye cultivars with higher viscosity of endosperm bread. The WE AXs present in breads obtained from inbred lines were characterized by the higher degradation degrees than those in breads from cultivars, as indicated by their HPSEC-RI profiles. This was associated with considerably lower proportions of 2-Xylp in their backbones. Besides, a level of endoxylanase activity in flours from inbred lines was much higher than that in flours from cultivars. Breeding of hybrid rye cultivars for production of high-viscosity bread requires the proper components. They may be preliminarily selected from populations with high WE AX contents and relatively low levels of endoxylanase activity by using the overall viscosity test for starting flours. However, further measurement of AX-dependent extract viscosity in test breads made from such lines may verify their usefulness completely.  相似文献   
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