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191.
Through the use of a critical electrolyte concentration staining technique, the glycosaminoglycans (GAGs) in the nucleus pulposus region of the canine intervertebral disc were arbitrarily identified as "hyaluronic acid", chondroitin sulphate and keratan sulphate. Approximate estimates of GAG concentration could be qualitatively deduced by determining the appropriate GAG "ALCIANOPHILIC INDEX". This index was considered to be an effective qualitative adjunct to chemical quantitation of GAGs in the intervertebral disc. 相似文献
192.
Based on the time that symptoms of blackleg become evident in the field and the various ways of inoculation, it is concluded that the spread of symptom expression is due to the depth at which the bacteria penetrate into the interior of the tubers. Moreover, it is demonstrated that it is not the closed lenticels which prevent penetration, but the absence of a waterfilm in the intercellular spaces of the tuber tissue. 相似文献
193.
A method for the separation of leucocytes from bovine blood and its separation into lymphocyte and granulocyte fractions is described. The method, involving flash lysis of the erythrocyte population, was found to yield large numbers of viable cells suitable for maintenance in tissue culture medium and hence of value in immunological studies. 相似文献
194.
195.
196.
P. GAILLARDON 《Weed Research》1975,15(6):393-399
A study of sorption phenomena between two triazine herbicides and humic acids Terbutryne is very readily adsorbed by humic acids while atrazine is only slightly adsorbed and this only in an acid environment. The influence of pH on adsorption and the competitive effect of the cations Ca2+, Al3+ and Fe3+ shows that the proton form of the molecules of the two herbicides can be adsorbed by an ion exchange-type mechanism; the neutral form of terbutryne molecules could be adsorbed by other mechanisms. Desorption of terbutryne is accompanied by a more marked hysteresis phenomenon in the case of neutral molecules, and, in an acid environment, calcium shows a weak capacity for displacement in relation lo the adsorbed herbicide. 相似文献
197.
A. Costagliola D. Russo A. A. Izzo P. Urbani V.
di
Marzo A. Cecio 《Anatomia, histologia, embryologia》2005,34(Z1):13-13
The endocannabinoid anandamide may regulate intestinal motility through activation of CB1 receptors. Anandamide is then inactivated by fatty acid amide hydrolase (FAAH), a membrane bound enzyme. Under pathological conditions, inactivation of such enzymatic activity may lead to inhibition of the intestinal motility. Here, preliminary reports on the distribution of Fatty Acid Amide Hydrolase (FAAH) immunoreactivity in the mouse gastrointestinal neurons, and the pharmacological effects of N‐arachidonoylserotonin (AA‐5HT), a selective inhibitor of FAAH, are reported. FAAH was revealed by an indirect immunofluorescence. Laminar preparations containing the myenteric or the submucous plexus adhered, were peeled off after the whole gut wall had been stretched out and fixed in 4% paraformaldehyde. They were subsequently incubated with a polyclonal anti‐serum directed against a region near the N‐terminus of the human FAAH and revealed by a FITC‐conjugated goat anti‐rabbit secondary anti‐serum. FAAH‐immunoreactive neurons were observed within the myenteric ganglia throughout the GIT. The positive nerve cells varied in size and density of immunoreactivity. Stomach and large intestine showed the highest neuronal density. AA‐5HT significantly reduced both gastric emptying and gastrointestinal tract transit. Such inhibitory effect was reduced by the C1 receptor antagonist SR141716A. Both morphological and pharmacological results suggest that FAAH may play a critical role in controlling gut anandamide levels. 相似文献
198.
199.
P. van de Graaf † M. E. Joseph J. M. Chartier-Hollis T. M. O'Neill 《Plant pathology》2002,51(3):331-337
A detailed study of conidial germination, germ-tube growth and the formation of infection structures in Phoma clematidina , the causal agent of clematis wilt, is described for two clematis varieties differing in disease resistance. On both the resistant and susceptible varieties, the fungus entered leaves and stems by direct penetration of the cuticle, often, but not always, following the formation of infection structures. More germ tubes per conidium were formed on the susceptible host, but these germ tubes were on average shorter than on the resistant host. Although germ tubes regularly entered the plant via trichomes, stomata were not found to be sites of entry. Following penetration of the cuticle of resistant plants, germ-tube growth was sometimes restricted to the subcuticular region, and halo formation occurred at the sites where penetration was attempted. Subcuticular growth and halo formation were not observed on susceptible plants. These observations may partly explain the resistance of small-flowered clematis varieties to P. clematidina . 相似文献
200.