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211.
IE Tóth 《Canadian Metallurgical Quarterly》1998,30(6-7):329-333
In the light of the observation obtained with the application of the viral-tract tracing method, the CNS connection of the adrenal gland, with focusing on the central nervous connection of the adrenal cortex is reviewed. 相似文献
212.
RL Gollub HC Breiter H Kantor D Kennedy D Gastfriend RT Mathew N Makris A Guimaraes J Riorden T Campbell M Foley SE Hyman B Rosen R Weisskoff 《Canadian Metallurgical Quarterly》1998,18(7):724-734
The authors used functional magnetic resonance imaging (fMRI) to determine whether acute intravenous (i.v.) cocaine use would change global cerebral blood flow (CBF) or visual stimulation-induced functional activation. They used flow-sensitive alternating inversion recovery (FAIR) scan sequences to measure CBF and blood oxygen level-dependent (BOLD) sensitive T2* scan sequences during visual stimulation to measure neuronal activation before and after cocaine and saline infusions. Cocaine (0.6 mg/kg i.v. over 30 seconds) increased heart rate and mean blood pressure and decreased end tidal carbon dioxide (CO2). All measures returned to baseline by 2 hours, the interinfusion interval, and were unchanged by saline. Flow-sensitive alternating inversion recovery imaging demonstrated that cortical gray matter CBF was unchanged after saline infusion (-2.4 +/- 6.5%) but decreased (-14.1 +/- 8.5%) after cocaine infusion (n = 8, P < 0.01). No decreases were detected in white matter, nor were changes found comparing BOLD signal intensity in cortical gray matter immediately before cocaine infusion with that measured 10 minutes after infusion. Visual stimulation resulted in comparable BOLD signal increases in visual cortex in all conditions (before and after cocaine and saline infusion). Despite a small (14%) but significant decrease in global cortical gray matter CBF after acute cocaine infusion, specific regional increases in BOLD imaging, mediated by neurons, can be measured reliably. 相似文献
213.
214.
Twenty-five patients with acute lymphoblastic leukaemia (ALL) aged 10 months to 43 years and twenty-five age and sex matched healthy control subjects were investigated in this study. Serum immunoglobulins A, G and M levels were measured by single radial immunodiffusion method and immune complex levels estimated by polyethylene glycol precipitation technique. Significant increase in immune complexes and decrease in immunoglobulin G were observed in the patients. Although not statistically significant, the patients had a lower mean level of immunoglobulin A, and a higher mean immunoglobulin M concentration than the controls. Hypoimmunoglubulinaemia observed in this study may contribute to the aetiology of ALL or be an effect of the disease. Raised immune complexes could result from specific antibodies combining with tumour associated or microbial antigens. Immunoglobulin G levels showed a significant positive correlation with survival in the patients. The adverse effect of reduced immunoglobulin G on the prognosis of ALL is probably due to compromised immunity in the patients. 相似文献
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216.
In addition to high efficiency, short analysis times and small sample volumes, a further attractive feature of capillary electrophoretic techniques is the possibility to achieve, high selectivities. Usually, selectivity control also allows improvement in the resolution. A simple way to enhance the selectivity of capillary electrophoretic separations is to add one or more surfactants above their critical micelle concentration, or in the case of chiral separations to add a chiral selector to the background electrolyte. Because of the dynamic structure of micelles, the aggregation of monomers and size of the micelles can be easily adjusted. This review describes the various type of surfactants used in micellar electrokinetic capillary chromatography, and the chiral selectors employed in enantiomeric separations by capillary electrophoresis. Factors affecting the selectivity are noted. A brief discussion is included of the selectivity enhancement obtainable in non-aqueous media. 相似文献
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218.
IE Eder A Stenzl A Hobisch MV Cronauer G Bartsch H Klocker 《Canadian Metallurgical Quarterly》1997,75(12):1753-1760
We previously detected elevated transforming growth factor beta-1 (TGF-beta1) serum levels in patients with invasive bladder carcinomas. In this study, we therefore investigated whether elevated serum levels correlate with enhanced TGF-beta expression in human bladder tumours. mRNA levels of TGF-beta1, -beta2 and -beta3 were reduced in bladder tumour tissue to 86%, 68% and 56%, respectively, of the levels in normal urothelium. On the other hand, TGF-beta1 protein levels were found to be higher in superficial tumours (Ta-T1) (mean level of 0.153 ng mg(-1)) and in invasive T2/T3 tumours (mean level of 0.104 ng mg(-1)) compared with normal urothelium (mean level of 0.065 ng mg(-1)). Invasive T4 tumours, however, contained only low amounts of TGF-beta1 (mean level of 0.02 ng mg(-1)). Neither in mean nor in individual patients were serum and tissue TGF-beta levels correlated with each other. Cell culture experiments on primary bladder cells revealed a 57% decrease in TGF-beta1 mRNA levels in tumour compared with normal epithelial cells. Tumour epithelial cells contained about two times higher levels of TGF-beta2 and TGF-beta3 mRNA than normal epithelial cells. Fibroblasts expressed about the same amount of TGF-beta1 or TGF-beta2 as epithelial cells. Yet, fibroblasts released only 19% and 13% of the amount secreted by tumour epithelial cells into the supernatant. TGF-beta3, on the other hand, was expressed by fibroblasts with higher levels than by epithelial cells. TGF-beta1 was the predominent isoform in bladder tissue and cells at protein as well as on mRNA levels indicating that TGFs-beta2 and -beta3 are of minor importance in bladder cancer. In summary, there is a lack of correlation between TGF-beta serum levels and TGF-beta expression in tumour tissue in bladder cancer. 相似文献
219.
Effect of roasted soybeans and corn on performance and ruminal and blood metabolites of dairy calves
Respiratory sinus arrhythmia (RSA) has been used as a non-invasive estimate of vagal tone to determine whether the reduction in resting heart rate commonly seen when humans are exposed to increases in the ambient pressure is associated with changes in vagal autonomic control. Two sets of divers (n = 4) were examined during two simulated saturation dives, one to 46 atmospheres absolute (ATA) and another to 37 ATA. A significant reduction in resting heart rate was seen in both dives upon exposure to high pressure compared with controls at 1 ATA. The reduction in heart rate seen at increased pressure was consistent regardless of respiratory rate, indicating that moderate changes in respiratory rate do not affect heart rate under these conditions. No changes in the overall magnitude of RSA were observed over a range of respiratory rates during either dive compared with control values at 1 ATA. During both dives, RSA was significantly larger (P < 0.05) at low respiratory rates compared with higher rates for both 1 ATA controls and at high pressure. The presence of a hyperbaric bradycardia strongly suggests that vagal tone is altered during hyperbaric exposure; however, the lack of change in the magnitude of RSA at high pressure brings into question the viability of using RSA as an accurate indicator of vagal tone and this lack of correspondence deserves further investigation. 相似文献
220.
Discusses the significance of L. D. Goodfellow's (see record 1939-01413-001) interpretation of the Zenith Radio experiments in telepathy. Goodfellow provided a model for critiquing anomalous findings and paranormal claims, stimulated later statistical developments, and anticipated research on sequential patterns in guessing behavior and on contemporary work in cognitive biases. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献