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The objective of this study is to compare the thermal stress changes in the tooth microstructures and the hydrodynamic changes of the dental fluid under hot and cold stimuli. The dimension of the microstructures of eleven cats’ teeth was measured by scanning electron microscopy, and the changes in thermal stress during cold and hot stimulation were calculated by 3D fluid–structure interaction modeling. Evaluation of results, following data validation, indicated that the maximum velocities in cold and hot stimuli were ??410.2?±?17.6 and +?205.1?±?8.7 µm/s, respectively. The corresponding data for maximum thermal stress were ??20.27?±?0.79 and +?10.13?±?0.24 cmHg, respectively. The thermal stress caused by cold stimulus could influence almost 2.9 times faster than that caused by hot stimulus, and the durability of the thermal stress caused by hot stimulus was 71% greater than that by cold stimulus under similar conditions. The maximum stress was on the tip of the odontoblast, while the stress in lateral walls of the odontoblast and terminal fibril was very weak. There is hence a higher possibility of pain transmission with activation of stress-sensitive ion channels at the tip of the odontoblast. The maximum thermal stress resulted from the cold stimulus is double that produced by the hot stimulus. There is a higher possibility of pain transmission in the lateral walls of the odontoblast and terminal fibril by releasing mediators during the cold stimulation than the hot stimulation. These two reasons can be associated with a greater pain sensation due to intake of cold liquids.  相似文献   
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Influence of the food plants ofHeliothis armigera (Hb.) on the degree of parasitism by exotic parasiteCotesia kazak Telenga (Hymenoptera: Braconidae) was studied in cages in the laboratory on 7 food plants such as cotton (Gossypium hirsutum L.), tomato (Lycopersicon esculentum Mill), okra [Abelmoschus esculentus (L.) Moench], Dolichos (dolichos lablab L.), pigeonpea [Cajanus cajan (L.) Millsp.], Cowpea (Vigna unquiculata (L.) and chickpea (Cicer arietium L.). To determine the preference of the parasite 2 test methods were employed. In single plant choice test cotton was most preferred. Next in order of preference were tomato and okra. Dolichos, pigeonpea, cowpea and chickpea were least preferred. In multiple choice test, however, cotton and okra were preferred followed by tomato. Parasites were seen visiting these plants very frequently and high parasitism was recorded on these plants. Chick pea, pigeon pea, cowpea and Dolichos were the least preferred food plants. There appears to be some difference in fecundity as affected by some food plants. Exposure on okra, cotton and tomato resulted in higher cocoon production as compared to pigeonpea, Dolichos, cowpea and chickpea. There was, however, no difference in sex-ratio and longevity of the progeny as affected by food plants. This exotic parasite should be released first in crops such as cotton, okra and tomato on whichH. armigera is a very serious pest in India and elsewhere. Contribution No. 140/86 of the Indian institute of Horticultural Research, Bangalore-560 089  相似文献   
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Summary The exudation pattern of carbohydrates by the roots of wheat in health and under the stress of its root-rot infection have been correlated. Qualitatively, greater number of sugars have been recorded in the healthy root exudate samples than in the inoculated series. Quantitatively, under the diseased condition of the plant, abundant release of ribose, maltose, raffinose and sucrose was recorded, while the release of glucose, fructose, galactose, xylose and rhamnose was found to be suppressed. Selective depletion of hexoses was found to be most pronounced. The liberation of total carbohydrates in the exudate medium got significantly diminished in the inoculated series. The possible explanation for these alterations in the carbohydrate levels in response to the pathogenesis byHelminthosporium sativum on its potential host have been discussed.  相似文献   
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The toxicity, persistence and effect on parasitism of 10 insecticides, eight fungicides and one acaricide on Trichogrammatoidea armigera Nagaraja, an egg parasitoid of a Helicoverpa armigera (Hb), were investigated in the laboratory and under field conditions. At field recommended dosages, the fungicides oxycarboxin, copperoxychloride, streptomycin sulphate + tetracycline hydrochloride and 2‐bromo‐2‐nitropropane‐1,3‐diol and the acaricide dicofol were safe, while the insecticide phosalone and fungicide tridemorph were moderately toxic to adults. All other insecticides tested, namely dimethoate, fenitrothion, monocrotophos, phosphamidon, endosulfan, cypermethrin, decamethrin, fenvalerate and fluvalinate, and the fungicides carbendazim, methyl thiophenate and carboxin were toxic to adults. A high level of parasitism was recorded for all fungicide treatments and for dicofol and fluvalinate. The larval stage of the parasitoid was more tolerant than other stages. The residual toxicity of all fungicides, and dicofol, did not affect the ability of the parasitoid to parasitize its host, while the insecticides phosalone and fluvalinate were slightly persistent, favouring 44.7% and 49.3% parasitism after 15 days. Residues of dimethoate, decamethrin, cypermethrin, fenvalerate, monocrotophos and phosphanidon were moderately persistent, while fenitrothion and endosulfan were persistent.  相似文献   
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International Journal of Peptide Research and Therapeutics - Infections with HCV, HBV and poliovirus are still considered to be substantial global health burdens. Vaccination is one of the most...  相似文献   
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Molecular Biology Reports - Monoclonal antibodies (mAbs) are widely employed as invaluable therapeutics for a vast number of human disorders. Several approaches have been introduced for the...  相似文献   
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Molecular Biology Reports - Both extreme usage of water in agriculture i.e., drought and flooding affect physiological and growth aspects of the plant as well as gene expression undertaken in water...  相似文献   
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