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121.
Advances in methodology for diagnosis of allergic skin disease   总被引:1,自引:0,他引:1  
Advantages of IDST for diagnosis of atopy and selection of antigens for hyposensitization include the following: 1. The test is widely accepted by clients. 2. The clinician can select individual test allergens based on the patient history and geographic location. 3. It has been the standard for diagnosing atopy in the dog for more than 40 years. Disadvantages of IDST include the following: 1. The test should be performed on a regular basis to maintain reliability. 2. Interpretation of test results is subjective. 3. The test is not standardized on the basis of the examiner, source of the allergen, or reproducibility. 4. There is occasional difficulty in performing the test (e.g., need for sedation). 5. Anaphylaxis is a potential risk. 6. A significant amount of office time is needed to perform the test. 7. Condition of the patient's skin (e.g., lichenification, hyperpigmentation, pyoderma) may preclude its use. 8. There is a possibility of failure to test for appropriate allergens. 9. There may be false-positive and false-negative reactions. 10. Other medications can interfere with the test (e.g., antihistamines, corticosteroids). Advantages of in vitro testing for diagnosis of atopy and selecting antigens for hyposensitization include the following.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
122.
The in-vivo toxicity data of 33 O,O-diethyl O-(1-alkyl-3-R″-1,2,4-triazol-5-yl) phosphorothioates, reported in Part I of this series, were subjected to multiregression analyses for the following organisms: Leptinotarsa decemlineata (larvae), Macrosiphum euphorbiae (aphids), Culex pipiens (adults), Spodoptera littoralis (larvae) and the rat. The activities were found to depend mainly on the steric parameters of R″, these being best expressed by the values L, B1 and B4 of the computer program STERIMOL. It was shown that there were different steric requirements for each species and these are discussed. The predictive values of the best equations were also estimated.  相似文献   
123.
The article considers the pathogenesis, clinical signs, diagnosis, and treatment of atopic dermatitis.  相似文献   
124.
Twenty-four hours of pre-treatment with AgNO3 increased the vase-life of flowers from 3 to 4 days for carnations kept in water or in preservative solutions after simulated transport conditions. A mixture of AgNO3 with sodium thiosulphate or with EDTA was considerably better than AgNO3, while such complexing agents as CDTA, EDDHA and EDPA were less effective. Determination of radioactive silver (Ag) in dissected carnation parts treated with different Ag complexes showed a positive correlation between vase-life and the amount of tracer Ag in the plants.  相似文献   
125.
A new class of compounds, derived from hydroquinones, has been synthesised and bioassayed for juvenile hormone activity on yellow mealworm (Tenebrio molitor), confused flour beetle (Tribolium confusum), and mediterranean flour moth (Anagasta kuehniella). Structure-biological activity relationships of the most significant products are tabulated and discussed. Two of the new compounds, 1, 4-bis(5-chloropent-4-ynyloxy) benzene (I) and 1-(5-chloropent-4-ynyloxy)-4-phenoxybenzene (II), showed outstanding activity in morphogenetic assay with T. molitor, and good field persistence. Product II is of particular interest for the control of various Homopteran species, mosquitoes, stored product pests and fire ants.  相似文献   
126.
In the search for new juvenile hormone analogues (JHAs), a general approach was chosen based on the substitution of the isoprene unit, that carries the epoxy function in the natural hormone JHIII, by 3,3,3-trichloropropyl, 2,2-dichlorocyclopropyl- methyl, 3,3-dichloroallyl, or 3-chloroprop-2-ynyl groups. Accordingly, several terpenoid aromatic JHAs were prepared with, or without, oxygen atoms in the aliphatic chain. Structure-biological activity relationships of the most active compounds toward the yellow mealworm (Tenebrio molitor) and the large cabbage white butterfly (Pieris brassicae) are given. With a view to preparing synthetically accessible analogues, some alkyl phenyl ethers were also made, which were not branched in the aliphatic chain and were related terminally to the most active compounds. They were only moderately active against insects when tested for morphogenetic activity, but exhibited a good field persistence. The occurrence of a moderate acaricidal activity among these analogues prompted the examination of several 1,4-disubstituted-phenyl derivatives. The ovicidal effectiveness of these products against a susceptible strain of the two-spotted spider mite, Tetranychus urticae, was ten or 100 times higher than that of the well known and highly potent JHAs.  相似文献   
127.
This work broaches the possibility of using place names as indicators of original landscapes that have been much transformed. The reconstruction of landscape elements from place names is commonly disputed because such daring notion is impossible to demonstrate. The present case avoids this by making a preliminary study of changes in the landscape using conventional methods. With the knowledge gained from objective and reliable sources, the possibility is analyzed of whether place names are a reflection of landscape changes taking place over a considerable period of time (the last few centuries). It is concluded that, for the present case study, in natural areas with a high rate of change of land use (Doñana Natural Park), place names indicate not only changes in the landscape, but also how such changes are perceived. In the study area, this is especially clear regarding the fens.  相似文献   
128.
A total of 74 embryos and fetuses were used in a comparative analysis of the epithelium of the non-glandular stomach compartments of merino sheep during development. The mechanical protection showed by the tegumentary epithelium in the superficial layers of the rumen, reticulum and omasum is supported by a buffer system of neutral mucopolysaccharides secreted by the deeper strata. Neutral mucopolysaccharides first appeared in epithelial cells at 46 days of fetal life. Acid mucopolysaccharides, mucins, and mucoid compounds were not detected. Growth curves and formulas were constructed for the epithelial layers.  相似文献   
129.
An electronic sphygmomanometer which functions on oscillometric principles, was used to measure arterial blood pressure in foals. Its accuracy was assessed by comparison with results obtained by direct measurement in anaesthetised pony foals, aged 34 to 64 days. Correlations between data obtained by the two methods were highly significant but the sphygmomanometric readings were consistently lower than those obtained by direct measurement. An equation was derived from the pooled values for mean, systolic and diastolic pressure measurements. This was used as a correction factor when the oscillometric method was employed in the field on Thoroughbred foals, during the first three days post partum, and on pony foals during the first day only. There were no significant differences between systolic, diastolic and mean values in Thoroughbreds on Days 1, 2 or 3 after birth. Measurements recorded on the first day after foaling were significantly lower (P less than 0.025) in ponies than in Thoroughbreds. Blood pressure measurements in Thoroughbreds and ponies were substantially higher than those reported previously using the ultrasonic Doppler technique.  相似文献   
130.
The records of 13 dogs with a crusting dermatosis of the mucocutaneous junctions, pressure points, and trunk were evaluated. All of the dogs had been fed corn- and wheat-based commercial dry dog foods that failed to meet the National Research Council's recommendations for balanced nutrition. The dermatosis in all 13 dogs resolved completely after the diet was changed to one that met the National Research Council's recommendations. The disease was similar to that which has previously been called canine dry pyoderma, but is now known to be a zinc-responsive dermatosis.  相似文献   
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