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Photodynamic therapy response in cats with cutaneous squamous cell carcinoma as a function of fluence 总被引:1,自引:0,他引:1
The response of advanced stage cutaneous squamous cell carcinomas (SCC) following treatment with photodynamic therapy (PDT) has been poor. It was the aim of this pilot study to determine whether an increase in the delivered fluence (i.e. energy density) would improve the duration of tumour remission in cats with advanced-stage SCC. Tumours were treated with aluminium phthalocyanine tetrasulphonate (AlPcS4 ) PDT at a fluence of either 100 J cm−2 or 200 J cm−2 and tumour response was evaluated at regular intervals. Those feline tumours treated with a fluence of 100 J cm−2 ( n = 8) had a significantly shorter median remission duration (69 days; range 0–619 days) than those feline tumours treated with 200 J cm−2 ( n = 6; 522 days; range 151–1057 days). It is our conclusion that a fluence of 200 J cm−2 is well tolerated and more effective when treating cats with advanced stage cutaneous SCC. 相似文献
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The mechanism by which some plant species develop resistance to the root parasite, broomrape ( Orobanche aegyptiaca ), is still not clear. Resistance to other pathogens can be induced by methyl jasmonate and systemic acquired resistance can be induced by treatment with salicylic acid, while cis -jasmone can act as a signaling molecule in plant–insect interactions. The three compounds studied, methyl jasmonate, cis -jasmone, and methyl salicylate, were applied to Arabidopsis thaliana seedlings that were then transferred to Nunc cell culture plates and exposed to the germinating seeds of O. aegyptiaca . The number of infections of the roots of single seedlings of A. thaliana was then quantified. Exposure for 24 h to very low concentrations of methyl jasmonate or methyl salicylate, which were then removed, effectively induced resistance to infection of A. thaliana by O. aegyptiaca , reducing attachment and tubercle formation by 90%. cis -Jasmone was far less effective in inducing a similar resistance to infection. These results support the view that methyl jasmonate can induce almost full resistance to infection by broomrape. The fact that such resistance is not observed under normal conditions of infection supports the idea that the root parasite does not evoke the full defensive response in the host plant. 相似文献
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The mechanism by which the flowering holoparasitic plant, Orobanche aegyptiaca , infects its host without evoking a defence mechanism is still poorly understood. In this work, we studied several mechanisms used by phytopathogenic fungi. We focussed on the possible role of peroxidases during O. aegyptiaca penetration into the roots of Arabidopsis thaliana . A convenient experimental system for studying the interaction under sterile conditions was developed. The formation of extracellular reactive oxygen species (ROS) was detected at the interaction site before, during, and after the parasite penetrated into the host. These extracellular ROS probably originated from the parasite. However, no intracellular ROS could be detected at the site of the interaction. Peroxidase activity was observed mainly at the apex of the root of the parasite and in the adventitious roots of the tubercle. Benzhydroxamic acid, a peroxidase inhibitor, was used to probe the possible role of peroxidase in the infection process. Peroxidase activity was observed in the root apex and adventitious roots of O. aegyptiaca, but no evidence was found for its participation in the actual infection process. Peroxidase activity was also found in the later stages of the interaction between the host and the parasite. We propose that peroxidases could have a role in generating extracellular ROS for loosening the cell wall of the host in order to facilitate penetration. Alternatively, the ROS could act in facilitating the root elongation of the parasite. 相似文献
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本研究旨在建立针对小反刍兽疫病毒(peste des petits ruminants virus,PPRV)H蛋白抗体的iELISA检测方法.以筛选的H蛋白B细胞表位为基础,选择反应原性较好的4个抗原表位肽串联后合成作为包被抗原,优化各步反应条件及筛选各种缓冲液,并确定检测临界值.经优化后,多表位抗原肽的最佳包被量为... 相似文献
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Comparison of the Strength and Holding Power of 4 Pin Designs for Use with Half Pin (Type I) External Skeletal Fixation 总被引:1,自引:0,他引:1
R. AVERY BENNETT DVM MS ERICK L. EGGER DVM DiplomateACVs MICHAEL HISTAND MS PhD ALFRED B. ELLIS DVM 《Veterinary surgery : VS》1987,16(3):207-211
The strength and holding power of four pin designs for use with half pin (type I) external skeletal fixation were evaluated. Pins that were tested were fully threaded, nonthreaded, two cortices partially threaded, and one cortex partially threaded. The study involved three parts: (1) resistance of the pins to axial extraction immediately after insertion; (2) resistance of the pins to axial extraction 8 weeks after being inserted into the tibiae of live dogs; and (3) resistance of the pins to bending load. Pins with threads engaging two cortices were more resistant to axial extraction than nonthreaded pins in both the acute (p less than 0.0001) and chronic (p less than 0.0001) studies. Nonthreaded pins were more resistant to bending than fully threaded and two cortices partially threaded pins (p less than 0.0005). One cortex partially threaded pins possessed similar bending strength to nonthreaded pins (p = 0.21) and had 5.3 times more resistance to axial extraction in the acute study (p less than 0.0001) and 6.9 times more in the chronic study (p less than 0.0001). Though one cortex partially threaded pins were not as resistant to axial extraction as pins with threads engaging two cortices (p less than 0.0001), they were more resistant to bending loads (p less than 0.0005). Loss of holding power and pin failure are two of the most serious problems associated with fracture stabilization using external skeletal fixation. The results of this study suggest that one cortex partially threaded pins are better at maintaining holding power and resisting bending and breaking than nonthreaded pins.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Niyokwishimira ALFRED Huan LIU Mu Lan LI Shao Feng HONG Hai Bo TANG Zu Zhang WEI Ying CHEN Fa Kai LI Yi Zhi ZHONG Wei Jian HUANG 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(6):643-651
Astroviruses are the principal causative agents of gastroenteritis in humans and have
been associated with diarrhea in other mammals as well as birds. However, astroviral
infection of animals had been poorly studied. In the present study, 211 rectal swabs
collected from cattle and water buffalo calves with mild to severe diarrhea were tested
for bovine astrovirus (BAstV) by RT-PCR. Results: 92/211 (43.6%) samples were positive for
BAstV, at a rate of 46.10% (71/154) in cattle and 36.84% (21/57) in water buffalo.
Phylogenetic analysis based on the partial and full-length of 25 ORF2 amino acid sequences
obtained in this study classified the Guangxi BAstVs isolates into five subgroups under
the genus of Mamastrovirus, genotype MAstV33, which
suggested that the water buffalo was a new host of this genogroup that previously included
only cattle and roe deer. Despite the origin of the host, the Guangxi BAstV isolates were
closely related to the BAstV Hong Kong isolates (B18/HK and B76-2/HK), but highly
divergent from the BAstV NeuroS1 isolate previously associated with neurologic disease in
cattle in the U.S.A. Nucleotide sequence-based characterization of the ORF1b/ORF2 junction
and corresponding overlapping regions showed distinctive properties, which may be common
to BAstVs. Our results suggested that cattle and water buffalo are prone to infection of
closely related astroviruses, which probably evolved from the same ancestor. The current
study described astroviruses in water buffalo for the first time and is thus far among the
largest epidemiological investigations of BAstV infection in cattle conducted in
China. 相似文献
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