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981.
CJ Jeng SA McCarroll TF Martin E Floor J Adams D Krantz S Butz R Edwards ES Schweitzer 《Canadian Metallurgical Quarterly》1998,140(3):685-698
To understand the influence of the ascending path linking area 17 to area 18 of visual cortices, experiments were carried out in which a small neuronal population of area 17 was inactivated with GABA, while unitary responses were recorded in area 18. In the latter, cells are identified as belonging to the simple or complex family according to their firing pattern evoked in response to sine-wave gratings scrolling through the receptive fields. Anesthetized cats were prepared for single-cell recordings. In area 17, a GABA-containing pipette was placed in superficial layers in order to inactivate reversibly a small neuronal population. Prior to blockade, the orientation tuning curves were obtained in both areas and the difference in optimal orientation between areas 17 and 18 was recorded. In area 18, cells were classified as simple or complex. The strategy was to study the reaction of neurons in area 18 prior to, during and after area 17 depression. In most simple cells, whenever the difference in orientation was in the iso-range, that is when the difference in optimal orientations of the injected site (in area 17) and of the neuron in area 18 was less than 30 degrees, the GABA application produced a decline of the evoked discharges, whereas GABA injection augmented the evoked firing rate when the difference was in the cross-range (>60 degrees). In contrast to simple cells, GABA depression enhanced the responses in the majority of complex cells with like orientations in both areas. When the difference between recording sites was in the cross-range, then area 17 depression produced weaker evoked firing. A tangential penetration of the injecting pipette, allowing injection of different orientation sites while testing the same unit in area 18, revealed that the latter could react with an enhancement or a decline of the responses as the injecting pipette shifted from iso (or cross) to cross (or iso) disparity in optimal orientations between areas 17 and 18. These results suggest that the path connecting area 17 to area 18 may be functionally discriminated on the basis of the orientation domain and cell types. In addition, our data suggest that the ascending visual streams are required to generate orientation specificity in area 18. 相似文献
982.
OBJECTIVE: To investigate the existence of an opioid stimulatory tone on growth hormone (GH) secretion in the human male. DESIGN: Seven healthy male volunteers, aged 19-30, were studied in the Endocrine Unit of the University of Sassari. GH-releasing hormone (GHRH), 100 micrograms as an intravenous (IV) bolus, as administered with and without preadministration of IV naloxone, 2 mg as a bolus followed by a constant infusion of 2 mg/h. Blood samples were taken for 120 minutes after GHRH administration. RESULTS: Naloxone significantly blunted the GH response to GHRH, measured either as mean peak value (at times 30 to 90) or as integrated concentrations. CONCLUSIONS: Naloxone is able to decrease the effect of a maximal dose of GHRH, thus suggesting the existence of an opioid stimulatory tone on GH secretion. 相似文献
983.
JC Mullen SA Schipper G Lemermeyer MJ Bentley 《Canadian Metallurgical Quarterly》1997,13(11):1045-1046
A 37-year-old male with long-standing heart murmur and ventricular septal defect developed acute chest pain and was diagnosed with an aortic dissection and aortic insufficiency. The ventricular septal defect and aortic dissection were repaired successfully as a combined procedure. At late follow-up (three years), he continued to enjoy an excellent result. 相似文献
984.
Nonsteroidal anti-inflammatory drugs and corticosteroids for the management of canine osteoarthritis
Anti-inflammatory medications have long been prescribed for relief of the pain and discomfort associated with OA. This occurs despite the recognized side effects associated with use of NSAIDs and corticosteroids. Available evidence suggests that NSAIDs provide this relief through a combination of central and peripheral actions. Recent discovery of two isoforms of cyclooxygenase has increased our understanding of NSAID activity and may result in identification of drugs that potentially will have fewer side effects. A review of NSAIDs used in veterinary medicine indicates that relatively little is known regarding their role in treating OA, although controlled studies involving carprofen and etodolac have increased our knowledge of the efficacy of specific NSAIDs used for this purpose. 相似文献
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988.
IuN Pokid''ko SA Isaeva EE Mnasina NP Danilova RG Vasilov 《Canadian Metallurgical Quarterly》1998,125(6):688-691
Antifungal activities of the compounds isolated from Kalopanax pictus against representative fungi of dermatomycosis were investigated using paper disc diffusion method. It was found that kalopanaxsaponins A and I were effective in inhibiting the growth of Candida albicans KCTC 1940 and Cryptococcus neoformans KCTC 7224 with minimum inhibitory concentration (MIC) of 25 micrograms/ml. It showed that antifungal activity of both compounds have strong selectivity against the fungi of dermatomycosis. 相似文献
989.
P Panayiotidis K Ganeshaguru C Rowntree SA Jabbar VA Hoffbrand L Foroni 《Canadian Metallurgical Quarterly》1997,97(4):844-847
Chromosome 13q deletion is among the most common cytogenetic abnormalities in chronic lymphocytic leukaemia (CLL). We investigated the 13q14.3 deletion in 44 CLL patients by Southern blotting following purification of clonal B CLL cells to >90%. Two sets of probes were used to investigate the site of clonal deletion, the D13S25 and D13S319 markers (at 13q14.3) and probes for exons 11 and 26-27 of the BRCA2 gene (at 13q12). Homozygous and heterozygous deletion at the 13q14.3 region was found in five and 17 patients, respectively. Despite the recent report of the BRCA2 gene involvement in >80% of CLL patients, we failed to detect a single case of homozygous or heterozygous deletion involving the 13q12 region. Our data support previous findings that the 13q14.3, and not the 13q12 region, is the major site of candidate tumour suppressor gene(s) in CLL. 相似文献
990.
J Mayet KP O'Kane R Elton HA Johnstone M Shahi MA Ozkor AV Stanton NR Poulter PS Sever RA Foale DJ Webb SA Thom 《Canadian Metallurgical Quarterly》1997,11(9):595-597
It has been suggested that the deletion polymorphism of the angiotensin-converting enzyme (ACE) genotype may be important in the development of left ventricular hypertrophy (LVH). In order to test this hypothesis we investigated the interaction between blood pressure (BP), LVH and ACE genotype in 86 previously untreated hypertensive patients. Each underwent two-dimensional and Doppler echocardiography and ACE genotyping. There were no significant differences in BP, the parameters of left ventricular structure (including left ventricular mass index) or diastolic function between the three genotype groups. Additionally, there were no significant differences in the relationship between systolic BP and left ventricular mass index among the three genotype groups (II genotype, r = 0.46, P = 0.02; ID genotype, r = 0.42, P = 0.01; DD genotype, r = 0.34, P = 0.10; F = 0.38). In contrast to some previous studies, we have found in this group of previously untreated hypertensive subjects no evidence to suggest that the deletion polymorphism of the ACE genotype is important in the development of LVH. 相似文献