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91.
EO Koylu PR Couceyro PD Lambert NC Ling EB DeSouza MJ Kuhar 《Canadian Metallurgical Quarterly》1997,9(11):823-833
CART peptide specific polyclonal antisera were raised in rabbits. The antisera were raised to CART peptide fragments that span most of the predicted CART protein. The specificity of each antisera was demonstrated by blockade of immunostaining by the immunizing peptide but not by the other CART peptide fragments. In the hypothalamus and pituitary of colchicine and noncolchicine treated rats, immunostaining was observed in cell bodies, fibers and varicosities. Clusters of cells were also stained in the adrenal medulla. It is noteworthy that cellular immunostaining was only found in areas previously shown to express CART mRNA. These findings indicate the presence of CART peptide(s) in the hypothalamus, pituitary, and adrenal gland. Furthermore, we also present evidence for the possible processing of the CART pro-peptide into smaller peptide fragments. These neuroanatomical findings suggest a role of CART peptides in hypothalamic, pituitary and adrenal function. 相似文献
92.
Management of critically ill patients is based on knowledge of fundamental physiological variables. Automatized and continuous measurement of these variables is preferable. A new system based upon the thermodilution method has been developed to measure cardiac output automatically and continuously. We evaluated the system in the potentially unstable perioperative period with possible great and rapid changes in cardiac output. Twenty patients, scheduled for open heart or abdominal aortic aneurysm surgery, were included into the study, which was approved by the local ethical committee. The patients were monitored for up to 30 hours. At random intervals five iced bolus thermodilution cardiac output (BCO) determinations were made and compared to the continuous measurements (CCO). Two hundred and thirty-one pairs of data were obtained. The cardiac outputs ranged from 2.5-14.9 l/min. The absolute bias was 0.31 l/min (95% limits of agreement -1.4 l/min to 2.0 l/min). The mean relative error was 4.7% with a standard deviation of the relative error of 15.4%. The linear regression was represented by: CCO = 11.352 x BCO - 0.36. The correlation coefficient R was 0.90 (p < 0.001). In conclusion, the CCO measurement technique is a promising clinical method. The method is straightforward, requires no calibration, is independent of vascular geometry and measures with its limitations volumetric flow. Finally automatic and continuous patient monitoring provides more information and has potential to reveal previously undetected haemodynamic events. 相似文献
93.
94.
PL Appleton NC Ellis PE Minchom V Lawson V B?ll P Jones 《Canadian Metallurgical Quarterly》1997,22(5):707-722
Examined self-reported depressive symptoms in 72 young people with spina bifida, ages 9 to 18:11, and matched able-bodied comparison subjects, using the Dimensions of Depression Profile for Children and Adolescents (Harter & Nowakowski, 1987). Independent variables included gender, self-perceptions (including physical appearance), and perceived social support. Young people with spina bifida were at greater risk of depressive mood, low self-worth, and suicidal ideation. Girls, independent of disability, were at greater risk of depressive mood, low self-worth, and self-blame. Multiple regression analyses suggest that global self-worth serves as a mediating variable for the effect of physical appearance self-concept on depressed mood (particularly in young people with spina bifida), and that perceived parental social support has a direct effect on depressed mood (particularly in girls). 相似文献
95.
The effects of low-frequency (50, 100, 200 and 400 Hz) 'suppressor' tones on responses to moderate-level characteristic frequency (CF) tones were measured in chinchilla auditory nerve fibers. Two-tone interactions were evident at suppressor intensities of 70-100 dB SPL. In this range, the average response rate decreased as a function of increasing suppressor level and the instantaneous response rate was modulated periodically. At suppression threshold, the phase of suppression typically coincided with basilar membrane displacement toward scala tympani, regardless of CF. At higher suppressor levels, two suppression maxima coexisted, synchronous with peak basilar membrane displacement toward scala tympani and scala vestibuli. Modulation and rate-suppression thresholds did not vary as a function of spontaneous activity and were only minimally correlated with fiber sensitivity. Except for fibers with CF < 1 kHz, modulation and rate-suppression thresholds were lower than rate and phase-locking thresholds for the suppressor tones presented alone. In the case of high-CF fibers with low spontaneous activity, excitation thresholds could exceed suppression thresholds by more than 30 dB. The strength of modulation decreased systematically with increasing suppressor frequency. For a given suppressor frequency, modulation was strongest in high-CF fibers and weakest in low-CF fibers. The present findings strongly support the notion that low-frequency suppression in auditory nerve fibers largely reflects an underlying basilar membrane phenomenon closely related to compressive non-linearity. 相似文献
96.
97.
A polyneuropathy is characterized by a symmetrical distribution of sensory or motor abnormalities, more pronounced distally than proximally and usually more evident in the lower than in the upper limbs. Polyneuropathies may be classified on the basis of (a) clinical picture: acute/subacute/chronic, sensory/motor/autonomous, axonal degeneration/segmental demyelinization, and (b) cause: metabolic disorder, deficiency, infection, auto(dys)immunity, hereditary and toxic/iatrogenic polyneuropathy, with idiopathic polyneuropathy as the remaining group. Damaged nerves may recover as the result of spontaneous remyelinization and axonal regeneration. Treatment is particularly successful in immunomediated neuropathies. Withdrawal is often successful in intoxications and suppletion in deficiencies. Even if no treatment is possible, the diagnosis is important: the patient can be taught to accept his disease and the prognosis can be determined, in connection with possible handicaps. 相似文献
98.
This study compared the intra-examiner and inter-examiner error of 2 constant force probes to the reading of a conventional manual probe. 3 examiners made repeated examinations of attachment level using a modified Florida probe and a manual North Carolina probe (read to 1 mm or 0.5 mm); relative attachment level measurements were made using a Florida disk probe. One probe was used in each quadrant in 8 subjects with moderate to advanced periodontitis. Error was calculated as the mean of the absolute value of the difference between each examination, and the correlation between values at each examination calculated. Statistically-significant differences between probe type, examiners, and sites were detected using a repeated measures ANOVA accounting for the nesting within subjects. There was a significant difference in error by probe type (modified Florida probe 0.62 +/- 0.03 mm, r = 0.86; Florida stent probe 0.55 +/- 0.05 mm, r = 0.82; manual probe to 1 mm 0.39 +/- 0.02 mm, r = 0.88; manual probe to 0.5 mm 0.40 +/- 0.02 mm, r = 0.89; (p < 0.001). Significant differences were observed by examiners (p < 0.01). These data indicate that both manual and controlled-force probes can provide measurement within less than 1 mm of error; however, individual calibration of examiners remains important in the reduction of error. 相似文献
99.
AP Andonopoulos M Tiniakou M Melachrinou H Sfountouris A Bounas C Zervas NC Zoumbos 《Canadian Metallurgical Quarterly》1997,64(5):287-292
A prfA gene encoding polypeptide release factor RF1 was cloned from Thermus thermophilus. T thermophilus RF1 shares 68% homology with Escherichia coli RF1, and its overproduction reduced readthrough translation of UAG, not of UGA, in the lacZ gene. Rapid purification of T thermophilus RF1 was achieved by T7-RNA polymerase driven overexpression of T thermophilus RF1 protein with a C-terminal histidine tag. 相似文献
100.
DM Edgar WF Seidel KW Gee NC Lan G Field H Xia JE Hawkinson S Wieland RB Carter PL Wood 《Canadian Metallurgical Quarterly》1997,282(1):420-429
Signal detectability was measured in three temporal conditions as a function of the bandwidth and configuration of simultaneous maskers that either did or did not spectrally overlap the signal. The 20-ms signal was 250 Hz wide and was centered at 2500 Hz (fs). Although there were marked individual differences, performance was typically poorer when signal onset came 1 ms rather than 250 ms after the onset of a 420-ms masker, and poorest when signal onset came 1 ms after the onset of a 23-ms masker. The results support the idea that two separate across-channel processes contribute to temporal changes in signal detectability. One process contributes to the improvement observed as signal onset is delayed from masker onset, and its influence is reduced by the presence of masking components at fs only when the masker extends exclusively below fs. The other process is associated with the improvement observed as masker offset is delayed from signal offset, and its influence is reduced by the presence of masking components at fs when the masker extends exclusively above, or both below and above fs. Both of these processes are primarily activated by frequencies ranging from 0.6 to 0.8fs and 1.2 to 1.4fs. The data also demonstrate that the measured critical bandwidth narrows as signal onset is delayed from masker onset. 相似文献