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41.
Features of paw edema induced by subplantar injection of actinomycin D (act D) were investigated in rats. The paw edema was produced as early as the 1st day and reached a maximal level on the 3rd or the 4th day. Thereafter, it began to subside progressively and was considerably reduced by the 16th day following act D (20 μgm) injection. A direct dose response relationship between the amount of act D injected and the intensity of the paw edema was obtained. No difference in β-glucuronidase and acid phosphatase activity was found between saline and act D-injected paws on the 2nd day. This was followed by an increase in the activity of both enzymes on the 4th, 8th, and 16th days after injection. The histamine content of the saline and act D-injected paws remained unchanged during the early phase of inflammation. A marked increase in the histamine content was noted during the late phase in the drug-injected paw. The effects of act D treatment on capillary permeability to Evans blue dye (EBD) and the edema formation of the paw revealed that a maximal increase in vascular permeability to EBD occurred on the 1st day and was maintained until the 8th day. In contrast to permeability, the paw edema on the 1st day was minimal and increased progressively until the 3rd or 4th day. Thereafter, both the permeability and the paw edema began to diminish and were considerably reduced on the 16th day. Aspirin and hydrocortisone treatment were ineffective in suppressing the act D-induced paw inflammation. Indomethacin produced a somewhat dose-related anti-inflammatory effect against the inflammation caused by this drug. 相似文献
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T. Cochrane A. W. Nathan R. S. Bexton C. Callicott R. A. J. Spurrell A. J. Camm 《Medical & biological engineering & computing》1984,22(1):19-23
A microcomputer-based pacemaker system for the evaluation of pacemaker treatment of tachycardia is described. The system may
be used to study tachycardia initiation, tachycardia termination or a combination of the two. The software incorporates a
visual display unit screen handling package which provides the user-system interface. System-patient interfacing is performed
by a separate pacing and sensing unit which communicates with the computer via standard digital input/output lines. Several
pacing options are available, selectable from a screen-displayed menu. Each selection also has an associated set of programmable
parameters which may be adjusted, within allowed limits, to suit particular studies. Examples of the use of the system for
tachycardia termination are given. The main programming language for the controlling software was Fortran IV. Some routines
were necessarily written in assembly language. The system is useful for evaluation purposes and forms the basis of a cardiac
pacemaker development tool. 相似文献
47.
Effect of brain and spinal cord injuries on motor imagery 总被引:1,自引:0,他引:1
Jean Decety Dominique Boisson 《European archives of psychiatry and clinical neuroscience》1990,240(1):39-43
Summary The timing of mentally executed movements was measured in ten patients with hemiplegia, tetraplegia and paraplegia. In hemiplegic patients a significant difference in mental duration times was found between the paralysed and the normal represented limb. The paralysed limb was mentally much slower than the healthy one. In contrast, movement times in tetraplegic and paraplegic patients did not differ from those in normal subjects. All patients reported a sensation of subjective effort accompanying the execution of the mental tasks. These observations are compatible with an outflow processing underlying motor imagery. 相似文献
48.
This article deals with some of the recent evidence bearing on the issues of the liability of benzodiazepines to lead to abuse, dependence, and adverse behavioral effects. Reviews of epidemiological, clinical and experimental literature indicated that the previous conclusion about abuse of these drugs still holds: the vast majority of the use of benzodiazepines is appropriate. Problems of nonmedical use arise nearly exclusively among people who abuse other drugs. Nevertheless, there are reasons for concern about patients who take benzodiazepines regularly for long periods of time. These drugs can produce physiological dependence when taken chronicaly, and although this does not appear to result in dose escalation or other evidence of psychological dependence, physiological dependence can result in patient discomfort if drug use is abruptly discontiniued. Also, physicians are currently prescribing shorter-acting benzodiazepines in preference to longer-acting benzodiazepines. The shorter-acting drugs can produce a more intense withdrawal syndrome following chronic administration. Furthermore, rates of use of benzodiazepines increase with age, and elderly patients are more likely than younger ones to take the drug chronically. The clearest adverse effect of benzodiazepines is impairment of memory. This, too, may be particular concern in older patients whose recall in the absence of drug is typically impaired relative to younger individuals, and who are more compromised following drug administration.This article was supported by USPHS Grant DA-00254 and by funding from Hoffmann-La Roche, Inc. 相似文献
49.
目的:探讨青少年特发性脊柱侧弯(adolescent idiopathic scoliosis,AIS)胸腰椎生理曲度变化情况以及不同类型侧弯之间胸腰椎生理曲度的差异。方法:自2017年1月至2021年12月回顾性分析305例脊柱全长正侧位X线片的青少年患者,根据有无侧弯分为正常组和侧弯组。正常组179例,男79例,女100例;年龄10~18(12.84±2.10)岁。侧弯组126例,男33例,女93例;年龄10~18(13.92±2.20)岁。观察并比较两组Risser征、胸椎后凸角(thoracic kyphosis,TK)与腰椎前凸角(lumbar lordosis,LL),并分析比较不同性别、不同程度侧弯与不同节段侧弯TK值与LL值。结果:侧弯组在女性比率(P=0.001)、年龄(P<0.001)方面均明显高于正常组;Risser征方面,正常组低级别骨化程度比率明显高于侧弯组(P=0.038)。侧弯组TK值明显小于正常组(P<0.001),而两组LL值比较,差异无统计学意义(P=0.147)。男性与女性之间比较,TK值与LL值差异无统计学意义。轻度侧弯TK值明显大于中度侧弯(P<0.05),但LL值比较,差异无统计学意义(P>0.05)。不同节段侧弯之间TK值与LL值比较,差异均无统计学意义(P>0.05)。结论:胸椎与腰椎生理曲度均与性别无关;AIS患者胸椎生理曲度变小,但是腰椎生理曲度基本不变。轻度AIS患者的胸椎生理曲度大于中度AIS患者,但是腰椎生理曲度在轻中度患者之间几乎无差异,且与正常青少年相似。AIS患者胸腰椎生理曲度变化可能与脊柱前柱相对生长过快有关,其具体机制有待进一步研究。 相似文献
50.
The acute interaction between opioid receptors and N-methyl-D-aspartate (NMDA) receptors on nociception was examined in rats using tail-flick and paw-pressure vocalisation tests. When injected at various times (1 to 6 h) after morphine (5 to 20 mg/kg, i.v.) or fentanyl (4x40 microgram/kg, i.v.), the opioid receptor antagonist naloxone (1 mg/kg, s.c.) not only abolished the opiate-induced increase in nociceptive threshold, but also reduced it below the basal value (hyperalgesia). The noncompetitive NMDA receptor antagonist MK-801 (0.15 or 0.30 mg/kg, s.c.) prevented the naloxone-precipitated hyperalgesia and enhanced the antinociceptive effects of morphine (7.5 mg/kg, i.v.) and fentanyl (4x40 microgram/kg, i.v.). These results indicate that the antinociceptive effects of morphine and fentanyl, two opiate analgesics widely used in humans in the management of pain, are blunted by concomitant NMDA-dependent opposing effects which are only revealed when the predominant antinociceptive effect is sharply blocked by naloxone. This study provides new rationale for beneficial adjunction of NMDA receptor antagonists with opiates for relieving pain by preventing pain facilitatory processes triggered by opiate treatment per se. 相似文献