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41.
Studies on bone marrow extracts from ten animal species have revealed the presence of thermostable antigens. Similar antigens were found in other organs as shown by immunodiffusion and cross-reactivity was demonstrated between the thermostable proteins from horse and dog and between cow and sheep proteins. Using an immunoenzymatic reaction with glucose oxidase as the marker, the thermostable antigens were localized in the blood and bone marrow polymorphonuclear leukocytes and the myeloid cell line. 相似文献
42.
Dr H. P. Drutz T. C. Mainprize Pam Tremblay K. R. Baker 《International urogynecology journal》1991,2(1):10-15
The combined effect of isopropamide 5 mg plus trifluoperazine 1 mg (a combined anticholinergic and alpha-adrenergic antagonist) (Smith, Kline and French Canada Ltd, Ontario, Canada), antibiotics, and bladder drill was retrospectively assessed on 100 consecutive women, aged 16 to 47 years, presenting with the signs and symptoms of the urethral syndrome. Assessment included history, physical examination, routine bacterial and chlamydial cultures (cervical, urethral, vaginal, and urine), cystourethroscopy, and urodynamics. Urodynamic diagnoses included detrusor sphincter dyssynergia (n=84), detrusor instability (n =8), external urethral sphincter spasticity (n=4), and sensory urgency (n=1). Three patients with positive urine cultures were excluded. Urethrotrigonitis was visualized at cystourethroscopy in all patients. Only one case of chlamydial urethritis-cervicitis was identified by culture: 82% of patients had a history of prior antibiotic therapy for lower urinary tract symptoms and 21% were being treated with antibiotics at the time of their initial assessment.Following 1 month of treatment, 44 (45%) patients were cured of all symptoms, 49 (51%) were improved, 3 (3%) were unchanged and 1 (1%) was worse. Significant changes in uroflowmetry included a reduction in postvoid residual urine volume from 49 ± 28 ml to 14 ±21 ml (P=0.029) in the unstable bladder group and a conversion from intermittent to continuous uroflow patterns in the detrusor sphincter dyssynergia group (P <0.005, 2) and overall (P <0.005, 2). A statistically significant number of patients (P <0.025, 2) converted from increased to normal tracings on repeat perianal electromyography, suggesting that the pathophysiology of the urethral syndrome is urethral spasticity related to urethral inflammation rather than actual infection.We conclude that detrusor sphincter dyssynergia, bladder instability, and urethral sphincter spasticity are the common urodynamic findings in the urethral syndrome. A combination of anticholinergic and alpha blocking agent, antibiotics, and a bladder drill markedly improved (96%) symptoms in women with the urethral syndrome. 相似文献
43.
The fine structure of the abdominal ganglion of Aplysia californica has been studied in preparations fixed by immersion in aldehydes, either directly or after a survival of a few hours in artificial sea water. The central core of neuropil is surrounded by a rind of neuronal cell bodies floating in a subcapsular space containing a loose meshwork of neuronal and glial processes, separated by wide extracellular spaces. Large primary processes with deeply infolded membranes leave the neuronal perikarya and enter the neuropil where they branch into smaller processes containing either neurofilaments, neurotubules or both. Some have the appearance of initial segments. The neuropil is not a homogeneous structure. Rather, four types of zones can be distinguished: (1) zones of fibers of passage coursing together in the neuropil and making few synaptic contacts: (2) zones of neurosecretory fibers containing large granules and dense-core vesicles, again making few synaptic contacts: (3) zones with a great variety of synaptic contacts between medium size and small profiles; and (4) glomerular zones. The differentiated membranes of the synapses are characterized by a slight increase in density and by being regularly parallel to each other. Presynaptic densities are sometimes quite prominent but specialized dense cytoplasmic opacities have never been seen bordering the postsynaptic membranes, i.e., all synapses are of the symmetrical type. Interlemmal opacities vary considerably in density. In zone 3, the synaptic vesicles are of several sizes, are round, oval or flat, and are either clear or filled with different types of dense material. The population of vesicles within a single profile may consist either of a homogeneous group of similar vesicles or of various mixtures of two or three kinds of vesicles. In profiles with mixtures of clear and large dense-core vesicles, it is often only the clear vesicles which agglomerate towards the differentiated membranes. In such cases the large dense-core vesicles lie as a peripheral halo around the clear vesicles. Here, and especially in other large neuronal profiles not forming contact in the plane of section, they can be seen to associate specifically with mitochondria and glycogen. It is proposed that they do not contain neurotransmitters but are related to mitochondrial activities such as the storage of ATP or the movement of calcium ions. In profiles with mixtures of clear and small dense-core vesicles, both types of vesicles often touch the presynaptic membrane, suggesting the release of two transmitters or of a modulator or neurohormone with a transmitter, by a single terminal. Serial synapses are present in this zone. The glomerular zones contain small profiles forming many synaptic contacts, some of which are arranged in such a way as to suggest the existence of "reciprocal" serial synapses. 相似文献
44.
Summary Abstinence signs were precipitated in rats by naloxone (1 mg·kg-1 s.c.) injected at various times (from 1.5 to 16 h) after a single dose of morphine hydrochloride (15 or 50 mg·kg-1 s.c.) administered incaqueous solution. Increasing the dose of morphine increased the latency of the phenomena and the duration of the underlying state shifts of signs as described by Bläsig et al. (1974) in chronically morphinized rats also occurred when increasing the dose of morphine and the time interval between the injections of morphine and of naloxone. Naltrexone and diprenorphine were also effective. These three antagonists, given before morphine, were able to prevent precipitated abstinence: however, naloxone was almost ineffective when the higher dose of morphine was used and when the time interval was long. In these latter conditions, naltrexone was definitely more effective and longer acting and diprenorphine still more so. The same characteristics were found for the protective action of the three antagonists in acutely morphinized mice and the same order for their potencies in precipitating abstinence in acutely morphinized mice. Like naloxone, naltrexone and diprenorphine facilitated a nociceptive reaction in normal mice.The abstinence signs precipitated in acutely morphinized rats or mice are probably not unmasked excitatory effects of morphine as such effects should have been increased rather than inhibited by previous administration of specific antagonists; they might correspond to potentiated effects of the antagonists themselves. The prevention by specific antagonists of the abstinence syndrome is most simply interpreted by antagonism (direct or indirect) of dependence induction, but other interpretations are not excluded. 相似文献
45.
Minor physical anomalies and family adversity as risk factors for violent delinquency in adolescence 总被引:1,自引:0,他引:1
Arseneault L Tremblay RE Boulerice B Séguin JR Saucier JF 《The American journal of psychiatry》2000,157(6):917-923
OBJECTIVE: Minor physical anomalies are considered indicators of disruption in fetal development. They have been found to predict behavioral problems and psychiatric disorders. This study examined the extent to which minor physical anomalies, family adversity, and their interaction predict violent and nonviolent delinquency in adolescence. METHOD: Minor physical anomalies were assessed in a group of 170 adolescent boys from low socioeconomic status neighborhoods of Montréal. The boys had been enrolled in a longitudinal study since their kindergarten year, when an assessment of family adversity had been made on the basis of familial status and the parents' occupational prestige, age at the birth of the first child, and educational level. Adolescent delinquency was measured by using self-reported questionnaires and a search of official crime records. RESULTS: Results from logistic regression analyses indicated that both the total count of minor physical anomalies and the total count of minor physical anomalies of the mouth were significantly associated with an increased risk of violent delinquency in adolescence, beyond the effects of childhood physical aggression and family adversity. Similar findings were not found for nonviolent delinquency. CONCLUSIONS: Children with a higher count of minor physical anomalies, and especially a higher count of anomalies of the mouth, could be more difficult to socialize for different and additive reasons: they may have neurological deficits, and they may have feeding problems in the first months after birth. Longitudinal studies of infants with minor physical anomalies of the mouth are needed to understand the process by which they fail to learn to inhibit physical aggression. 相似文献
46.
L-DOPA-induced dyskinesias are one of the main problems encountered in treating patients with Parkinson's disease (PD). They are induced by the antiparkinsonian medications and primarily related to the degree of dopaminergic depletion, as shown by the fact that they tend to appear several years after the onset of the disease. Do the initial therapeutic decisions taken in treating a PD patient influence the point at which dyskinesias first occur? This question is raised in view of the apparent priming phenomenon that occurs in first exposure to L-DOPA. L-DOPA administrated to an MPTP intoxicated monkey rapidly corrects the animals' motor symptoms but generate dyskinesias. In contrast, the administration of dopaminergic agonists with a long half-life has a similar therapeutic effect but without inducing dyskinesias. However, a parkinsonian monkey that had received L-DOPA and developed dyskinesias, which were subsequently abolished when the treatment was withdrawn for several months, proceeded to develop dyskinesias when treatment with dopaminergic agonists with long half-life was introduced. The monkeys' previous exposure to L-DOPA (i.e. priming) thus increased its susceptibility to develop dyskinesias after exposure to drugs which would not otherwise have had this effect. Pulsatile activation of type D2 dopamine receptors is reported to be the principal factor in the triggering of dyskinesias and may well be involved in the priming phenomenon. While the pathophysiological basis of priming is not yet known, the phenomenon would not appear to be related to a hyperexpression of dopamine receptors (types D1 and D2) in the sensorimotor striatum. The results of recent experiments have given rise to several different hypothesis for the mechanisms involved in priming: the role of internalization of dopamine receptors after administration of dopaminergic drugs; change in the distribution of D3 dopamine receptor; changes in the expression of peptides (substance P, enkephalin) in efferent neurons of the striatum; and reorganization of connections at the level of the dopaminergic neurons and their target tissue. While many questions remain unanswered, it may well be that the initial therapeutic decisions taken when treating de novo patient are crucial in trying to delay the onset of dyskinesias. 相似文献
47.
Veno-venous continuous renal replacement therapy for burned patients with acute renal failure 总被引:6,自引:0,他引:6
Tremblay R Ethier J Quérin S Béroniade V Falardeau P Leblanc M 《Burns : journal of the International Society for Burn Injuries》2000,26(7):638-643
From 1995 to 1998, 12 burned patients with acute renal failure (ARF) were treated by veno-venous continuous renal replacement therapy (CRRT) at the Burn Unit of H?tel-Dieu de Montréal. Their mean (+/-SD) age was 51+/-12 years, and the mean burned surface covered 48.6+/-15.8% of total body surface area. All patients were mechanically ventilated and presented evidence of sepsis. The mean delay before occurrence of ARF was 15+/-6 days and ARF was mainly related to sepsis and hypotension. Main reasons for CRRT initiation were azotemia and fluid overload. A total of 15 CRRT modalities were applied (12 continuous veno-venous hemodiafiltration, CVVHDF; two continuous veno-venous hemofiltration, CVVH; and one continuous veno-venous hemodialysis, CVVHD) over 14+/-13 days. For CRRT, nine patients received heparin and three were not anticoagulated. Mean values for dialysate and reinjection flow rates were 1134+/-250 ml/h and 635+/-327 ml/h, respectively. Admission weight was 78.8+/-12.7 kg with a mean weight gain before CRRT initiation of 10.0+/-5.8 kg and a mean weight loss during CRRT of 8.9+/-5.5 kg. Nine patients received enteral plus parenteral nutrition, and three, parenteral nutrition only; the total caloric intake was 31.5+/-7.0 kcal/kg/day and protein intake, 1.8+/-0.4 g/kg/day. The normalized protein catabolic rate (nPCR) was evaluated at 2.28+/-0.78 g/kg/day during CRRT. The mortality rate was 50%. The six survivors all recovered normal renal function with four of them requiring intermittent hemodialysis for short periods. In conclusion, veno-venous CRRT is particularly well suited for this selected population allowing smooth fluid removal and aggressive nutritional support. 相似文献
48.
Behavioural Development in Children of Divorce and Remarriage 总被引:4,自引:0,他引:4
Linda Pagani Bernard Boulerice Richard E. Tremblay Frank Vitaro 《Journal of child psychology and psychiatry, and allied disciplines》1997,38(7):769-781
We employed an autoregressive modelling technique with data from the Quebec Longitudinal Study to prospectively examine the developmental impact of family transition on behaviour while controlling for predivorce and preremarriage effects. Teachers rated children's anxious, hyperactive, physically aggressive, oppositional, and prosocial behaviour every 2 years from kindergarten through to the end of elementary school.Once individual and parental characteristics and antecedent family events were controlled, children who experienced parental divorce before age 6 exhibited comparatively more behavioural disturbance than their peers whose parents divorced later. With the exception of a protective effect on hyperactive behaviour, remarriage did not have a significant impact on children's behaviour when the legacy of divorce was controlled.Although the results suggest that children of divorced parents show difficulty in many areas of functioning, the effects of family transition on behavioural development were dependent on the child's age and the specific behavioural dimension assessed.Compared to other points in development, early childhood divorce was associated with long-term increases in anxious, hyperactive, and oppositional behaviour during later childhood.The effects of divorce on children's fighting were short-lived.Unlike previous prospective studies that suggest predivorce effects, we did not observe behavioural disturbance prior to divorce or remarriage. 相似文献
49.
Jean-François Tremblay Lucas Sideris François A. Leblond Jean-Sébastien Trépanier David Badrudin Pierre Drolet 《International journal of hyperthermia》2016,32(6):643-647
Background: The use of electrocautery devices is associated with complications such as perforation or fistulisation when used near intestinal structures. This is likely due to its effect on vascularisation of the bowel wall. To test this hypothesis we established a murine model to quantify the effect of electrocautery injury on the intestinal microvascularisation.Methods: Sprague-Dawley rats were subjected to five electrocautery injuries on the small bowel in coagulation mode (30 W intensity) and in cut mode (40 W, 80 W and 200 W intensities) for durations of 1, 2 and 5?s. 5?mg/kg of fluorescein was injected intravenously, the injured bowel segments harvested and the rat sacrificed. The segments were analysed to measure the fluorescence of injured bowel compared to adjacent unharmed tissue.Results: A significant decrease in bowel wall microvascularisation occurred with increasing intensity (coag 30 W/cut 40 W versus cut 200 W 1?s: p?0.05) and duration of electrocautery injury (cut 40 W 1/2?s versus 5?s: p?0.05). There was a 40% perforation rate when decreased bowel wall microvascularisation was 25% or more. Despite similar electrocautery injury, a significantly greater microvascularisation decrease was observed in jejunum compared to ileum (p?0.05).Conclusion: We successfully established a murine model to quantify the decrease of bowel wall microvascularisation associated with electrocautery use. Unsurprisingly, the decrease in microvascularisation is greater with higher intensity and duration of electrocautery and is associated with more perforations in the experimental model. The jejunum seems more vulnerable to electrocautery injury than the ileum. These observations support caution when using electrocautery devices near intestinal structures. 相似文献
50.
BACKGROUND: Laser‐mediated cell ablation is a powerful tool that has been used to understand cell fate in a variety of externally developing organisms but has not been used during mammalian post‐implantation development. RESULTS: We describe a method pairing laser ablation with murine embryo culture and establish parameters that can be used to precisely ablate cells in the selected field with minimal disruption to adjacent cells or the underlying cell matrix. Ablation of a large domain of endoderm, followed by ~1 day of culture results in a phenotypically normal embryo and gut tube, indicating that laser ablation is compatible with normal development. We next focused on one of the three precursor populations that have been shown to produce the liver bud. Ablations of a single progenitor domain result in a unilateral delay in the liver bud while the contralateral side is unaffected. CONCLUSIONS: We demonstrate that laser ablation is a specific and useful technique for studying cell fate in the mouse embryo. This method represents a powerful advance in developmental studies in the mouse and can be used to provide information on the specification of organs, differentiation, cell migration, and vital tissue interactions during development. Developmental Dynamics, 242:1202–1209, 2013. © 2013 Wiley Periodicals, Inc. 相似文献