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Background: Investigators in the authors' laboratory previously established the critical participation of the cerulospinal noradrenergic pathway in muscular rigidity elicited by fentanyl. The identification of colocalization of glutamate with tyrosine hydroxylase in most locus ceruleus neurons suggests a role for cerulospinal glutamatergic neurotransmission in fentanyl-induced muscular rigidity. This suggestion and the subtype(s) of glutamate receptors involved were investigated here.

Methods: Electromyographic signals activated by bilateral microinjection of 2.5 micro gram fentanyl into the locus ceruleus were recorded differentially from the left sacrococcygeus dorsi lateralis muscle of adult male Sprague-Dawley rats. The effect of intrathecal administration at the lower lumbar spinal cord of various N-methyl-D-aspartate (NMDA) and non-NMDA receptor antagonists or agonists on this index of muscular rigidity was studied. Rats were under mechanical ventilation, and intravenous infusion of ketamine (30 mg [center dot] kg sup -1 [center dot] h sup -1) was maintained until 10 min before fentanyl was administered.

Results: Microinjection of fentanyl bilaterally into the locus ceruleus increased the root mean square and decreased the mean power frequency values of electromyographic signals. The efficacy of fentanyl to elicit muscular rigidity in this manner was significantly reduced by previous intrathecal administration of either 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX), (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine maleate (MK-801), D-(-)-2-amino-5-phosphonovaleric acid (AP5), or (+/- (CPP). Intrathecal administration of kainic acid or NMDA also resulted in significant electromyographic activation.  相似文献   

43.
Epiderrnolysis bullosa (EB), a heterogeneous group of rare, inherited disorders, is manifested by recurrent blistering of the skin induced by the slightest trauma. Little information exists regarding the nutrition management of patients with EB. This study presents information on growth, identifies potential nutrition problems, and provides guidelines for nutrition management of persons with EB. Eighty patients attending a dermatology clinic for EB patients are described. Severity of disease ranged from mild blistering of the knees, elbows, and feet to extensive blistering and scarring of the skin and entire gastrointestinal tract. Of the 18 children with EB simplex, which is a mild form of the disease, 4 (22%) were at nutritional risk. None of the 13 adults with EB simplex were underweight and 8 (62%) were overweight. Of the patients with the more severe forms of EB, 27 of the 35 (77%) children with dystrophic EB and 4 of the 7 (57%) children with junctional EB were at risk for malnutrition. Of the 7 adults with dystrophic EB, 6 (86%) were underweight. Common nutrition problems included protein-energy malnutrition, chewing and swallowing problems, constipation, anemia, and vitamin/mineral deficiencies. When nutrition care protocols address these problems, growth, development, and nutritional status can improve. For those with severe nutrition problems, gastrostomy feeding or similar nutrition therapies should be considered. J Am Diet Assoc. 1995; 95:575-579.  相似文献   
44.
A 5-Year experience of 51 endoscopic transthoracic dorsal sympathectomies for idiopathic palmar hyperhidrosis in 26 patients is presented. Fifty-two percent complained of excessive sweating over their hands, 28% of axillary sweating and 20% over both areas, with a mean duration of 10 years. The second, third and fourth thoracic ganglia and their interconnecting fibres on the affected side were ablated using diathermy cautery. Over a mean follow up time of 26 months, this procedure was successful in curing or improving intractable sweating in 92%. However, axillary sweating was less well controlled than in the palms with 20% of patients describing residual wetness in the axilla. Compensatory sweating (75%) and gustatory sweating (48%) were the commonest side effects; despite this, most patients were satisfied with the functional and cosmetic outcome. Other complications included a temporary Horner's syndrome in one patient, a pneumothorax in the immediate post-operative period in another and a unilateral non-infective reactionary pleural effusion in a third. Two patients developed recurrence of palmar hyperhidrosis within 6 months of surgery. One has been successfully treated by re-operation on the affected side. All patients complained of mild to moderate interscapular chest pain which was easily controlled by non-steroidal anti-inflammatory agents, and resolved within 7–10 days post-operatively. The technique of endoscope transthoracic sympathectomy is effective, relatively simple to perform and usually requires only an overnight stay. It is recommended as the surgical treatment of choice for upper limb hyperhidrosis unresponsive to conservative measures.  相似文献   
45.
Perceptions of family cohesion and hierarchy structures were assessed by theFamily System Test (FAST), a clinically-derived figure placement technique. Parents (N=140) and their preadolescent offspring (N=70) completed typical and conflict representations in individual as well as group settings. Typical representations were characterized by balanced family structures (i.e. cohesive and moderately hierarchical) and those displaying conflict situations showed predominantly unbalanced patterns. FAST portrayals were related to respondent (mother vs. father vs. child). Fathers represented typical family relations as balanced more often than mothers. Regarding conflict representations, children were more likely than fathers to portray the family as unbalanced. However, analyses of representations of the same family (i.e. intra-family comparisons) indicated that all respondents differed in their perceptions and, that fathers' typical portrayals showed most often the same structure as those done by the family members as a group.  相似文献   
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Identification of Alcohol Abuse and Alcoholism with Biological Parameters   总被引:3,自引:0,他引:3  
The prevalence and incidence of heavy alcohol consumption are major problems which have been increasing in many countries in recent years. It is crucial for physicians to consistently identify early drinking problems as well as the various end disease states in order to minimize suffering and maximize recovery. This paper reviews the evolutionary development of clinical tools for detection of alcohol abuse. The focus is primarily on clinical/biochemical indicators of alcohol abuse, emphasizing but not limited to changes in hematological characteristics, liver enzyme activity, lipids, immune function factors, hormones, neurological factors, and some physically based tests. Use of test combinations and sophisticated statistical analysis of pattern changes in test batteries evidence increased diagnostic efficiency.  相似文献   
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We examined the relationship of history of alcoholism in first-degree relatives to neuropsychological performance of alcoholics abstinent from several weeks to several years. Eighty-four men were assigned to four groups based on "strength" of family history of alcoholism. The groups were: (1) "strong history," a parent plus another first-degree relative positive; (2) "moderate," parent only positive; (3) "weak," nonparent first-degree relative only positive; and (4) "negative," no first-degree relative positive. There were no significant between-group differences in NP performance. In other analyses there were no NP differences between alcoholics classified positive or negative purely on basis of paternal alcoholism, and no differences between subjects who had multigenerational versus unigenerational versus negative familial histories of alcoholism. It is concluded that genetic loading for alcoholism does not significantly affect the NP status of abstinent alcoholic groups equated for education, drinking history, and medical risk.  相似文献   
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