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91.
SM Lele ES Gloster ER Heilman PC Chen CK Chen AP Anzil JN Pozner MJ Reardon 《Canadian Metallurgical Quarterly》1997,24(3):193-196
In adult mammals fever is associated with the reduction of blood plasma iron level. Immature mammals, however, show either a decrease (precocial animals such as guinea pig neonates) or a lack of reduction (altricial animals such as human neonates) of plasma iron in response to endotoxin. In order to determine whether this difference is connected with maturity just after delivery, plasma iron concentration, hematocrit, body temperature and body mass were measured in rat pups injected with E. coli endotoxin in doses of 50 or 200 micrograms kg-1. Rat pups, like human neonates, are altricial animals. In 7-day-old rats injection of LPS led to a dose-dependent decrease in plasma iron level. The fall in plasma iron was accompanied by changes in body temperature and body mass. The results showed that plasma iron response to endotoxin in altricial rat neonates is similar to that observed in precocial guinea pig pups. 相似文献
92.
In thin film magnetic field sensors, strains adversely affect the gain and bias conditions. A new linear field sensor combining two matched spin valve elements is described. The difference signal from these two elements measures the strain at the field sensor and the sum signal, with the difference as input, gives a strain-compensated measure of the field 相似文献
93.
94.
ES Hansen 《Canadian Metallurgical Quarterly》1997,32(3):223-233
The present study aimed to demonstrate conditioned inhibition of Pavlovian conditioning of autonomic responses in humans. Subjects (N = 21) were presented initially with four geometric shapes (A, B, C and D). An electric shock served as the unconditioned stimulus (US) during acquisition. Conditional stimuli lasted for 8 s and US onset coincided with CS offset. Subjects were trained with A-US, C-US, and AC-US pairings and AB alone and B alone presentations. The subsequent summation test consisted of C-US pairings and CB alone and CD alone presentations. Conditioning was evident in self-reported US expectancy and first and second interval electrodermal responses. Evidence for conditioned inhibition during the summation test was found in US expectancy and second interval electrodermal responses. 相似文献
95.
96.
A direct ultrasound ranging system (DURS) has been developed for the quantitative evaluation of gait velocity. DURS consists of a transponder worn by the subject, a base unit infrared (IR) emitter/ultrasound (US) receiver, and a laptop computer. During gait analysis the transponder is worn by the subject at the approximate level of the body center of mass. As the subject walks away from the base unit his or her forward progression is displayed in real-time on the computer. At the end of the walking trial the instantaneous velocity profile, or gait velocigram (GVG), for that trial is displayed on the computer screen. From the GVG, parameters such as, gait speed, cadence, step length, step time, peak-to-peak variation, and time to achieve steady state walking are calculated and displayed. In addition gait deviations are readily apparent on the GVG. 相似文献
97.
98.
We report a case of gastric outlet obstruction simulating gastric antral neoplasm resulting from a perforated Meckel's diverticulum. Presentation of this nature has not been previously reported. 相似文献
99.
A Boffi E Chiancone ES Peterson J Wang DL Rousseau JM Friedman 《Canadian Metallurgical Quarterly》1997,36(15):4510-4514
Flash photolysis experiments have been carried out for the first time on a hemoglobin ferrous cyanide adduct with an 8 ns laser pulse. A 95% nonexponential rebinding process occurs within 2 micros after full photolysis in ferrous cyanide dimeric Scapharca inaequivalvis hemoglobin (HbI), indicating that once photolyzed the cyanide anion is not able to escape from the protein matrix and rebinds to the heme iron. The resonance Raman spectrum of the 10 ns photoproduct is identical to that of the fully relaxed deoxy derivative, indicating that in the ferrous cyanide HbI adduct protein relaxation occurs within 10 ns after photolysis. This behavior is at variance with that of the carbonmonoxy HbI derivative in which very little geminate rebinding is observed and the photoproduct relaxes with a lifetime of 1 micros. The fast relaxation of the cyanide HbI photoproduct can be accounted for by the small perturbation of the heme structure induced by cyanide binding to ferrous HbI. This is consistent with a deoxy-like conformation of the HbI ferrous cyanide adduct and implies that the pathway for relaxation involves only minor local rearrangements of the heme moiety. Photolysis experiments carried out on ferrous cyanide horse myoglobin, which can be saturated only partially, show a qualitatively similar behavior in ligand rebinding, indicating that the geminate process of the cyanide anion is a general phenomenon in hemoproteins. 相似文献
100.
SD Detera-Wadleigh JA Badner T Yoshikawa AR Sanders LR Goldin G Turner DY Rollins T Moses JJ Guroff D Kazuba ME Maxwell HJ Edenberg T Foroud D Lahiri JI Nurnberger OC Stine F McMahon DA Meyers D MacKinnon S Simpson M McInnis JR DePaulo J Rice A Goate ES Gershon 《Canadian Metallurgical Quarterly》1997,74(3):254-262