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201.
Fentanyl is used in small animals for perioperative analgesia during anaesthesia. Severe bradycardia and asystole were observed on bolus administration of a 3 µg/kg loading dose of fentanyl in two dogs under isoflurane anaesthesia. Premedication with 10 µg/kg glycopyrrolate did not prevent asystole in the first case; and although bradycardia was treated with 5 µg/kg glycopyrrolate administered intravenously in the second case, the heart rate continuously decreased and asystole subsequently developed. Asystole in both cases was quickly corrected by intravenous administration of 0 · 04 mg/kg atropine and closed chest compressions. This case report describes asystole induced by fentanyl administration in isoflurane anaesthetised dogs. Atropine was more effective than glycopyrrolate in the treatment of fentanyl‐induced asystole.  相似文献   
202.
A new prenylated flavanone from the roots of Sophora flavescens.   总被引:3,自引:0,他引:3  
S S Kang  J S Kim  K H Son  H W Chang  H P Kim 《Fitoterapia》2000,71(5):511-515
A new prenylated flavanone was isolated from the roots of Sophora flavescens. The structure of the new compound was elucidated as (2S)-7,4'-dihydroxy-5-methoxy-8-(gamma,gamma-dimethylallyl)-flavanone (1) on the basis of chemical and spectral evidence.  相似文献   
203.
A genic male-sterility gene newly induced by chemical mutagenesis, tentatively designated as ms-h(t), was located on the molecular map of rice and tested for its effect on chalky endosperm. Bulked segregant analysis was used to determine the chromosomal location of the ms-h(t) locus by screening four to five RFLP markers per chromosome. After confirming that the gene was located on chromosome 9, twenty-four RFLP markers from chromosome 9 were surveyed for polymorphism in the parents of the mapping population. Of these, eleven markers were mapped around the ms- h(t) locus. RG451 and RZ404 flanked the ms-h(t) gene, at 2.5cM and 3.3cM, respectively. Heterozygous F2 to F4 progenies were tested for co- segregation of male-sterility and chalky endosperm and it was revealed that ms-h(t) might have a pleiotropic effect on chalky endosperm. This mutant would be a good biological material to characterize the biochemical mechanism of male sterility and related pleiotropic effects. Further studies should be needed to know the usefulness of this mutant for hybrid seed production. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
204.
The solvatochromic behavior of indonaphthol dye was described. The UV/Vis absorption spectra of this compound have been studied in 5 solvents of different polarity. The solvatochromism of indonaphthol dye is discussed with the aid of semiempirical calculations.  相似文献   
205.
The several disazo dyes having different alkyl substituents were synthesized to dye unmodified polypropylene fiber. The affinity of the dyes onto unmodified polypropylene was increased with the increase of the length of alkyl substituents. Therefore, the heptyl-substituted dye having the longest alkyl group in this experiment showed very high color strength of dyeings with K/S value of over 24 at maximum absorption wavelength. The color fastnesses to washing, rubbing and light were also improved significantly for the longer alkyl substituted dyes, so that the heptyl-substituted dye exhibited a rating of 4∼5 for all kinds of fastnesses.  相似文献   
206.
The dye chemosensor for mercury ion detection was designed, which was based on donor-acceptor intramolecular charge transfer system and the corresponding fluorescence changing property was successfully monitored. This new dye chemosensor was containing dimethylcarbamodithioate groups to coordinate Hg2+, which showed very effective sensing functions. But it showed no significant changes upon the addition of other metal ions such as Ca2+, Pb2+, Al3+, Ce2+, Ba2+, Ni2+, Cd2+, Zn2+, and Mg2+.  相似文献   
207.
Pine wilt disease, caused by the pine wood nematode (PWN, Bursaphelenchus xylophilus), is a major threat to pine forests throughout East Asia. Nonetheless, its mechanism of invasion has not yet been described in detail. To better understand the pathology of this disease, it is important to examine the distribution of PWNs within pine tissue during the course of disease development. We attempted to stain nematodes with fluorescein-conjugated wheat germ agglutinin (F-WGA) as a means to locate and track the spread of PWNs. Although PWNs proliferated on Botrytis cinerea fungus were successfully stained only on their vulvas and spicule holes, PWNs extracted from inoculated Pinus thunbergii seedlings were stained on their surface. Stainability, or the percentage of PWNs stained with F-WGA over more than half of their surface, was about 20% by 1 day after inoculation, but increased to 80% at 10 days. The stainability of PWNs extracted from a 5-cm main stem segment that included the inoculation site was less than that of PWNs extracted from other parts of the main stem farther away (i.e., those that had dispersed). These results suggest that stainability is related to dispersal activity in time. Thus, to raise the stainability of PWNs at shorter timeframes after inoculation, PWNs with more than 80% stainability were re-inoculated into pine seedlings. This resulted in more than 70% stainability from 1 to 6 days after inoculation. In F-WGA stained thin paraffin sections of pine tissue of re-inoculated seedlings, PWNs brightly fluoresced under epifluorescence and were easily detected against the dark background of pine tissue. This staining technique with F-WGA is an excellent tool for detecting PWNs in pine tissue.  相似文献   
208.
Genetic transformation is an important technique for functional genomics study and genetic improvement of plants. Until now, Agrobacterium-mediated transformation methods using cotyledon as explants has been the major approach for cucumber, and its frequency has been up to 23%. For example, significantly enhancement of the transformation efficiency of this plant species was achieved from the cotyledon explants of the cultivar Poinsett 76 infected by Agrobacterium strains EHA105 with efficient positive selection system in lots of experiments. This review is to summarize some key factors influencing cucumber regeneration and genetic transformation, including target genes, selection systems and the ways of transgene introduction, and then to put forward some strategies for the increasing of cucumber transformation efficiency. In the future, it is high possible for cucumber to be potential bioreactor to produce vaccine and biomaterials for human beings.  相似文献   
209.
Herein, we report the synthesis and dyeing property of cationic copper phthalocyanine (cationic CuPc). The synthesized cationic CuPc was characterized using UV-Vis spectra and it showed good solubility in aqueous solution over a wide pH range. The dyeing of cationic CuPc was successfully employed onto acrylic fiber. The dyeing of acrylic fiber using cationic CuPc was achieved using conventional method. The effects of five important variables such as liquor ratio, dye concentration, dyeing time, temperature and pH were examined on the color strength (K/S) of dyed acrylic fiber. The maximum color strength was obtained at lower liquor ratio (100:1), higher dye concentration (6 %), longer dyeing time (60 min), 120 °C and alkaline condition (pH 11).  相似文献   
210.
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