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81.
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83.
Zusammenfassung Im Mai 1970 traten im Bereich eines Textil-Veredlungswerkes auffällige Schädigungen an der Vegetation von Hausgärten auf. Das Schadbild entsprach einer Wuchsstoffeinwirkung; die Empfindlichkeit der Pflanzen war unterschiedlich. Anhand von Labor- und Gewächshaustesten konnte als Ursache die Immission eines Fä rbereihilfsmittels (Carrier) angenommen werden; es handelte sich dabei um einen substituierten Aromaten.
Summary Injuries to vegetation caused by a substance (Carrier) used for textile dyeing. In may 1970 an extraordinary case of injury to vegetation in the range of a textile dye-work occured. The symptoms were equal to those induced by auxins. A so called carrier substance, it concerned a substituted aromate, was indicated as causal agent.
  相似文献   
84.
The distribution of six compounds with three different polyphenol skeletons have been studied in Rosmarinus officinalis: phenolic diterpenes (carnosic acid, carnosol, and 12-O-methylcarnosic acid), caffeoyl derivatives (rosmarinic acid), and flavones (isoscutellarein 7-O-glucoside and genkwanin), each showing a characteristic behavior and distribution during the vegetative cycle. Only in leaves were all six compounds present, and the highest accumulation rate was related with the young stages of development. Rosmarinic acid showed the highest concentrations of all the polyphenols in all organs. The distribution of this acid in leaves, flowers, and stems suggests that in the first stages of flower growth, levels were due to in situ biosynthesis, and in the last stages, the contribution of transport phenomena was increased. The antioxidant activity of six extracts with different polyphenolic composition was evaluated in aqueous and lipid systems. The results clearly suggest that rosemary extracts are excellent antioxidants in both aqueous and lipid systems.  相似文献   
85.
A genuine biophysical method, Fourier transform-infrared (FT-IR) spectroscopy has become a versatile research tool in biochemistry and biomedicine. Topical applications in microbiology and prion research are impressive illustrations of the vigorous evolution of the technique. FT-IR spectroscopy has established itself as a powerful method for the rapid differentiation and identification of microorganisms, thereby contributing to both clinical medicine and the prevention of bioterrorism. It has also led to considerable progress in various other fields of basic research, not least in prion sciences. In this field, FT-IR spectroscopy has been increasingly applied as a tool for elucidating structural features of the pathological prion protein, and also to study the molecular changes induced by prions in neuronal tissue and blood. This article sets out to give a review of current examples of the analytical potential of FT-IR spectroscopy in microbiology and prion research.  相似文献   
86.
In-vitro susceptibility testing provides valuable informations for choosing the most suitable antimicrobial agent for the control of bacterial infections in animals. Different diffusion and dilution methods, as conducted according to various approved performance standards, can be used to determine the in-vitro susceptibility of bacterial pathogens. In the present article, problems are discussed which arise from the use of different methods and the difficulty to interpret such results. While most approved performance standards were designed for testing of bacteria from human sources, the NCCLS document M31-A2 exclusively focusses on susceptibility testing of bacteria isolated from animals and--in contrast to all other standards--includes veterinary specific breakpoints for a number of antimicrobial agents used in veterinary medicine. Therefore, performance of in-vitro susceptibility testing of veterinary pathogens should follow the recommendations given in the NCCLS document M31-A2. The microdilution method is recommended as the method of choice for susceptibility testing. The result of a microdilution test is given as the minimum inhibitory concentration (MIC). This value provides a quantitative result which precisely indicates the degree of susceptibility of the tested bacterial strain and in return gives the veterinarian a clear guidance whether therapeutic intervention with the antibiotic in question will be successful.  相似文献   
87.
OBJECTIVE: To detect and characterize the full range of chlamydial infections in cats with ocular disease by use of polymerase chain reaction (PCR) assays, cytologic examination, immunohistochemical analysis, and evaluation of clinical information including status for feline herpesvirus-1 (FeHV-1). SAMPLE POPULATION: DNA extracted from 226 conjunctival samples obtained from cats with clinically diagnosed keratitis or conjunctivitis and 30 conjunctival samples from healthy cats. PROCEDURE: PCR assays for the 16S rRNA gene specific for the order Chlamydiales and a new Chlamydophila felis (formerly Chlamydia psittaci) species-specific 23S rRNA gene were performed. Seventy-four conjunctival samples were prepared with Romanowsky-type stain, grouped on the basis of inflammatory pattern, and screened for chlamydial inclusions by use of immunohistochemical analysis. Clinical information and FeHV-1 status were recorded. RESULTS: 26 (12%) specimens had positive results for the only known feline chlamydial pathogen, C felis. Surprisingly, an additional 88 (39%) were positive for non-C felis chlamydial DNA. Identification of non-C felis chlamydial DNA by direct sequencing revealed 16S rRNA gene sequences that were 99% homologous to the sequence for Neochlamydia hartmannellae, an amebic endosymbiont. Chlamydial prevalence was significantly higher in cats with ocular disease. CONCLUSIONS AND CLINICAL RELEVANCE: Application of a broad-range detection method resulted in identification of a new agent associated with ocular disease in cats. Finding chlamydia-like agents such as N hartmannellae in coinfections with their obligate amebic host, Hartmannella vermiformis, raises questions about the potential role of these microorganisms in causation or exacerbation of ocular disease in cats.  相似文献   
88.
Lactoferrin (LF), a glycogen of the transferrin family with anti-bacterial and immunomodulatory properties, is expressed in various secretions and tissues. Cutaneous LF serves as a mast cell stabilising compound, modulates T cell activity and is found during IgE-mediated late phase reactions at allergen challenged sites. Culicoides hypersensitivity (CHS) in horses is a common IgE-mediated allergic dermatitis, characterised by an early and late phase cutaneous reaction upon allergen challenge. The aim of the study presented here was to examine whether LF mRNA expression in skin biopsies from horses affected by CHS prior to and 4h following intradermal challenge with a commercial C. nubeculosus extract is modified in comparison to skin biopsies from non-affected horses. In order to obtain reliable data, real time PCR was performed and genes of interest were normalized using three different housekeeping genes, beta-actin, GAPDH, beta-2-microglobulin. In comparison to non-affected horses, higher variation in LF mRNA levels both prior to and post-intradermal challenge with C. nubeculosus extract was seen in horses affected by CHS. However, the statistical analysis demonstrated that LF mRNA expression was not significantly different between CHS affected and non-affected horses prior to intradermal challenge with C. nubeculosus extract. Intradermal injection of C. nubeculosus extract did not result in local upregulation of LF mRNA at 4h post-injection. LF mRNA expression was therefore not significantly different pre- or post-intradermal challenge with C. nubeculosus extract in either group. Our data indicate that clinically normal skin of horses affected by CHS is not characterized by modified maintenance levels of LF mRNA. In contrast to human skin allergen challenged sites, LF mRNA levels in horses affected by CHS are not significantly different to that of control sites at 4h post-injection of C. nubeculosus extract.  相似文献   
89.
以产志贺毒素样大肠杆菌(SLTEC)F18ab血清型标准菌株107/86基因组DNA为模板,利用PCR技术成功扩增出编码F18ab完整菌毛操纵子fed基因,克隆入表达载体pBR322,经限制性内切酶酶切分析,DNA琼脂糖电泳鉴定并结合序列测定分析,构建和筛选出含fed完整基因正确插入的pBR322-fed重组质粒,将上述重组质粒转化至不含任何菌毛结构的大肠杆菌SE5000,该表达重组菌能分别与兔抗F18ab亚单位蛋白FedF高免血清、鼠抗F18ab菌毛a单因子单克隆抗体、兔抗F18ab菌毛高免血清和抗F18ab菌毛IgG抗体产生明显的凝集反应。用热抽提法分别抽提和纯化SLTEC F18ab标准株107/86和重组菌SE5000(pBR322-fed)体外表达的F18ab菌毛,纯化菌毛经SDS-PAGE电泳和考马斯亮蓝染色获单一相对分子质量约为15 000蛋白条带。Western-blotting结果表明:兔抗F18ab菌毛高免血清能特异性识别SLTEC F18ab标准株107/86和重组菌SE5000(pBR322-fed)所提纯的单一主要结构蛋白。用重组菌SE5000(pBR322-fed)进行易感仔猪小肠上皮细胞体外黏附试验和黏附抑制试验,结果表明:重组菌SE5000(pBR322-fed)和SLTEC F18ab标准株107/86一样具有较强的黏附易感仔猪小肠上皮细胞的能力,而兔抗F18ab菌毛高免血清能有效地抑制上述重组菌SE5000(pBR322-fed)和SLTEC F18ab标准株107/86对易感仔猪小肠上皮细胞的黏附结合。  相似文献   
90.
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