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911.
912.
D. F. Shepeli 《Pharmaceutical Chemistry Journal》2005,39(8):428-432
Salmus is a product of Salvia sclarea technology that is widely used in balneary practice. It is established that the analytical characteristics of salmus substance,
as stipulated in the temporal pharmacopoeial article VFS 42-1530-85, are not objective and should not be used for evaluating
the quality of the ready-to-use preparation and for monitoring the process of its manufacturing. TLC data show that salmus
contains all components of sage oil (Russian State Standard GOST 3171-76) except for linalyl acetate. Qualitative specific
color reactions on Silufol TLC plates showed for the first time the presence of flavonoids such as kaempferol, quercetin,
juglanin, quercitrin, and rungioside and revealed one previously unknown substance, probably, of a flavonoid nature. The TLC
data also showed the presence of condensed tannins and chlorophylls. It is suggested to perform quantitative analysis and
identification of biologically active substances in salmus using methods for determining the content of reducing sugars (carbohydrates)
and oxidizable components. New procedures for determining the sum of essential oils and flavonoids using the total content
of extractable components have been developed and verified. It is suggested that these substances are among the main therapeutic
components of salmus.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 39, No. 8, pp. 33 – 36, August, 2005. 相似文献
913.
Tc-99m HMPAO was used to evaluate cerebral perfusion in a patient with tuberous sclerosis. The SPECT images demonstrated reduced HMPAO uptake in regions corresponding with MRI-confirmed locations of cortical tubers. These results indicate that the lesions are characterized by vascular perfusion deficits and support the hypothesis that cortical tubers result from developmental abnormalities of the embryonic central nervous system. 相似文献
914.
Esophageal pH monitoring is the accepted standard for the investigation of gastroesophageal reflux (GER) in adults. A postal questionnaire was sent to 912 United Kingdom paediatric physicians & surgeons. Five hundred forty-seven (61%) replied, with 124 (22.7%) currently using the technique, mostly in conjunction with barium swallow and/or esophagoscopy. The use of pH monitoring to quantify GER was also accepted in principal as being the best determinant of reflux by a further 186 (34%), but as yet was unavailable in their hospitals. Pediatricians were also questioned as to their management of children with GER. The majority were treated medically with a variety of antireflux medication, with only 237 (42%) referring cases for surgery. 相似文献
915.
916.
J R Glowa J D Bacher M Herkenham P W Gold 《Progress in neuro-psychopharmacology & biological psychiatry》1991,15(3):379-391
1. Rhesus monkeys were equipped with a novel intracerebroventricular (i.c.v.) cannula system and trained to respond under operant schedules of food presentation or termination of stimuli associated with the delivery of shock (escape). 2. CRH decreased food-maintained behavior in a dose-related manner over the range of (0.3-10 micrograms/kg) but did not affect escape responding, demonstrating a selective effect on food-maintained responding. 3. This selective effect was related to the tendency for responding to stop after delivery of a food pellet when higher doses of CRH were given, consistent with the notion that a conditioned aversion to food was established in the presence of CRH. 4. This may suggest that in hyperaroused clinical states such as depression and anorexia nervosa, focus is shifted away from appetitive tasks as a result of increased levels of CRH. 相似文献
917.
P Peretti-Viton D Margain O Arnaud A M Perez-Castillo N Graziani 《Journal of neuroradiology. Journal de neuroradiologie》1991,18(2):173-188
Three types of lymphoma of the central nervous system are known: primary non-Hodgkin's malignant lymphoma (NHML), secondary NHML and neurological lesions of Hodgkin's disease. NHML's are rare tumours, often associated with immunodeficiency and presenting predominantly as neuropsychological disorders. In this study 8 patients were explored by CT and MRI, with pathological confirmation. None of our patients had AIDS. The most typical neuroradiological image of this type of tumour is that of a large and intensely contrast-enhanced tumoral mass which is often multifocal and periventricular with infiltration of the subarachnoidal spaces and leptomeninges. Mass effect and perifocal oedema are less pronounced than expected with tumours of that size. NHML's may totally regress under corticosteroid therapy. This tumour of obscure aetiology must be recognized as it is now increasingly frequent. 相似文献
918.
919.
Release of the endogenous transmitter, glutamate, was measured from individual cone photoreceptors using a microfluorometric technique. The assay for glutamate was conducted within the lumen of a suction pipette, and was based on the fluorometric measure of the production of NADH from NAD+. This reaction was catalyzed by glutamate dehydrogenase contained in the pipette. Upon introduction of glutamate to the pipette, an increase in the NADH fluorescence was observed, representing the stoichiometric conversion of glutamate to NADH. The fluorescent signal was quantified, allowing an estimate of glutamate release from a single cone upon depolarization. The release observed was elicited upon depolarization of the cell with extrinsic current, and was detectable simultaneous with stimulation of the cell. Depolarization-induced release of endogenous glutamate was from the synaptic pedicle of the cell, and this release decreased with subsequent stimulations. The decrease in the release could be briefly reversed by an increase in the depolarization current used, or by allowing the cell to rest for several minutes. 相似文献
920.
Gordon J. Harris Ph.D. Instructor Jonathan M. Links Ph.D. Associate Professor Godfrey D. Pearlson M.B. B.S. Director Edwaldo E. Camargo M.D. Associate Professor 《Psychiatry research》1991,40(3):167-180
We developed a semiautomatic method termed “cortical circumferential profiling” for objective analysis of cerebral cortex function in emission tomographic neuroimaging studies. This method treats cortex as a continuous ring near the outer brain edge. A computer algorithm samples the cortex at 60 contiguous, equiangular locations, using 1-cm2 samples. These values are plotted as a function of cortical angle to produce the cortical circumferential profile. This method was used in a study of regional cerebral perfusion in 15 patients with Alzheimer's disease and 8 elderly control subjects using N-isopropyl [I-123]-iodoamphetamine. Cortical circumferential profiling decreases variability, examines the entire cortex within slices at preselected levels above the orbital-meatal line, and facilitates intrasubject and intersubject comparisons. 相似文献