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71.
72.
Possibilities of involution of changes in lesser circulation after closure of experimental aortopulmonary anastomosis were studied. 37 observations at various intervals after closure of anastomosis (several minutes to 13.5 months) in 25 dogs were analyzed. Before closure the anastomosis had functioned for 1-7 months. The results of histological examinations of lungs, pressure measurements in lesser circulation, heart weight, electrocardiographic and spirographic examinations were analyzed. It was found that complete involution of changes in lesser circulation was possible only in first month of existence of anastomosis, in this case with changes of both "early" and "late" types. "Late"-type changes after four months function of anastomosis had both reversible and irreversible character, whereas "early"-type changes became irreversible already after three-month duration of anastomosis. With the "late"-type changes, the operation itself (closure of anastomosis) was accompanied by symptoms of pulmonary vasomotor paresis and heart failure, whereas in the presence of "early"-type changes the operation elicited no morphological or functional changes. 相似文献
73.
A new program capable of rapidly and accurately reducing a two-dimensional X-ray diffraction pattern obtained from a Debye-Scherrer or Gandolfi camera to a quantitative digital diffractogram is described. By implementing geometric optimization routines based on the symmetry and sharpness of diffraction lines, the optimal configuration of the camera, X-ray path, and sample can be determined, thus providing the best possible set of integration parameters. Results for NIST standard reference materials 640c (Si) and 676 (Al2O3) are included to illustrate program functionality. 相似文献
74.
Six asthmatic children were studied to determine whether supplemental, parenteral atropine would increase the effects of bronchodilation and protection against exercise-induced bronchoconstriction after maximal effects had been achieved by inhalation. First, we determined the amount of inhaled atropine sulfate that would give maximal bronchodilation for each patient at rest. This quantity of atropine was designated as "A." Then all subjects exercised for five sessions with the following pre-exercise treatments in a random order: (a) inhaled distilled water plus intramuscular (IM) saline solution; (b) inhaled A dose of atropine plus IM saline solution; (c) inhaled distilled water plus 0.35 mg IM atropine; (d) inhaled A dose of atropine plus 0.35 mg IM atropine; and (e) inhaled double the A dose plus IM saline solution. The results showed that the combination of inhaled and IM atropine had the greatest bronchodilation effect and the greatest protection against exercise-induced bronchoconstriction. Atropine inhalation alone (A dose) or IM injection (0.35 mg) was not as effective in bronchodilation or in alleviation of exercise-induced bronchoconstriction. Doubling the dose of inhalation (2A) did not increase the effects of the A dose. These results support the hypothesis that inhaled atropine does not reach all the airways where cholinergic receptors are present. 相似文献
75.
76.
War is a complex social situation due to the interplay of multiple factors. Economical and political ones are of utmost importance, but human attitudes and motivations must be also taken into account. Being desirable to modify human transactions in such a way that they do not interfere with the basic right of everyone to a condition of physical and mental well-being, war must be abolished. The author contends that an understanding of behaviour through Psychology can be helpful in that aim. Aggression is considered the principal psychological cause of war. It is worth while to differentiate between aggression as an instrument for attaining a special end, and as pure hostility. Only in the first form, it is held here, does it play an important role in war. Psychogists must deal also with a wide range of states of mind that can be "served" by aggression: feelings of inferiority or insecurity, fear, greed, projections, compensations, rationalizations, etc. Scientific approach is not the only one Physiology brings to war prevention. It is equally important the wide dissemination of its conclusions among the general public. Information on the dynamics that prompt people to decide war would make it easier to control. This applies not only to political or military leaders, but also to civil populations. Concerning those two possible contributions of psychologists, scientific and educative, it is suggested the extensive use of psychodramatic techniques. Their richness lie in the lifelike experiences they convey to the participants, and particular aptitude to promote changes of attitudes. Investigation and information on the psychological processes related to war should be undertaken by international organizations of social scientists, acting simultaneously in several countries. Some of the initial steps they could further: 1) that prevention of war be a current subject matter in psychological courses; 2) that the World Health Organization take interest in this subject; 3) that psychologists participate in international political and economical bodies in order to clarify the psychological factors leading to war. 相似文献
77.
Holahan Matthew R.; Taverna Franco A.; Emrich Stephen M.; Louis Meira; Muller Robert U.; Roder John C.; McDonald Robert J. 《Canadian Metallurgical Quarterly》2005,119(6):1563
Male Long-Evans rats were injected with 32 ng/μl of the N-methyl-D-aspartate (NMDA) receptor antagonist 3-(2-carboxypiperazin-4-yl) propyl-1-phosphonic acid (CPP) or vehicle and trained to locate a hidden platform in a different location (reversal training) than used on the initial 4 days of training. Rats treated with vehicle or CPP into the dorsal hippocampus, basolateral amygdala, or mediodorsal striatum had similar latencies to locate the platform on the reversal day. Rats infused with CPP into the dorsal hippocampus or mediodorsal striatum failed to search preferentially in the novel location during a 24-hr, drug-free retention test, whereas all other groups searched preferentially in this location. Therefore, blocking dorsal hippocampal or mediodorsal striatal NMDA receptors selectively blocked long-term spatial retention without producing short-term performance deficits. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
An arrayed waveguide grating based multiplexer and interrogator for Fabry-Perot sensors 总被引:2,自引:0,他引:2
In this paper, we propose an interrogation system capable of multiplexing four identical Fabry-Perot (FP) interferometric sensors using two wavelength-division multiplexing devices. One is a 40-channel DWDM channel monitor, the other a four-channel CWDM device. The sensors are connected to the output channels of the CWDM device in order to assign a portion of the spectrum to each sensor. The reflected spectra are then analyzed using the DWDM channel monitor. By monitoring the power incident on each of the DWDM channels, the four sensor reflection spectra can be reconstructed in software and information relating to the measurand obtained. Based on software simulations and previous laboratory experiments with single sensors, it is predicted that this system would be capable of interrogating four EFPI strain sensors simultaneously at frequencies greater than 5 kHz with a resolution of approximately 2 /spl mu//spl epsiv/ and a range of 3000 /spl mu//spl epsiv/. 相似文献
79.
In many popular visions of ubiquitous computing, the environment proactively responds to individuals who inhabit the space. For example, a display magically presents a personalized advertisement, the most relevant video feed, or the desired page from a secret government document. Such capability requires more than an abundance of networked displays, devices, and sensors; it relies implicitly on recommendation systems that either directly serve the end user or provide critical services to some other application. As recommendation systems evolve to exploit new advances in ubiquitous computing technology, researchers and practitioners from technical and social science disciplines must collaborate to address the challenges to their effective implementation. Although it may be impossible to perfectly anticipate each individual's needs at any place or time, ubiquitous computing will enable such systems to help people cope with an expanding array of choices. 相似文献
80.
In June of 2004, Eddie Goldfinch will be retiring from his dutiesas Executive Editor of Radiation Protection Dosimetry (RPD).Oxford University Press is publishing the journal, however itshould be noted that Eddie has not completely stopped his publishingactivities or his association with RPD. He will remain as anemeritus member of the Editorial 相似文献