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61.
In three groups of six mice each, the α- and β-receptors were blocked by phentolamine and propranolol. The mice in the three groups then received an intravenous bolus injection of saline solution, epinephrine, and insulin, respectively. Cortical bone capillaries from the tibia diaphysis were submitted to transmission electron microscopy (TEM). The lumen and endothelium were measured and the results compared. Significant changes were only noted in the endothelium after the administration of insulin. These findings suggest that there are also insulin receptors in bone. Furthermore, they support previous findings in similar studies with epinephrine.  相似文献   
62.
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The syndrome of senile gait   总被引:1,自引:0,他引:1  
Summary Infrared computed stroboscopic photometry was used to quantify the kinematic profiles of walking in 10 elderly patients with symmetrical neurological disturbances of gait and in 19 age-matched neurologically healthy people. Clinical examination of the patients revealed similar profiles of walking even though their diagnoses were vascular dementia (2), normal pressure hydrocephalus (2), Alzheimer dementia with possible normal pressure hydrocephalus (2), mixed Alzheimer and vascular dementia (1), peripheral neuropathy (1), Alzheimer dementia with parkinsonian features (1), and un determined (1). Quantitatively, the patients' gait kinematics deviated greatly from control values, but these deviations were statistically attributable to reductions in stride. We suggest that many gait disturbances in elderly people are similar, regardless of etiology, because the characteristics of these gait disturbances are heavily veiled by nonspecific stride-dependent changes that comprise the syndrome of senile gait.  相似文献   
64.
65.
Cattle were immunized with glycoprotein IV (gIV) from bovine herpes virus-1 (BHV-1). Groups of five animals were then given either 2, 3, 4, or 5 doses of interleukin-2 (IL-2) (0.5 microgram/kg) at 12-hr intervals. Animals that received no IL-2 exhibited specific immune responses that are typical for BHV-1 infection, i.e. enhanced specific cytotoxicity, lymphocyte proliferative responses to gIV, and increased gIV-specific (ELISA) and virus-neutralizing antibodies. Treatment of animals with five doses of IL-2 significantly augmented all of these responses except serum neutralization (P less than 0.05). Furthermore, the dose of IL-2 that was selected did not induce any non-specific responses, i.e. hypergamma-globulinaemia, changes in blood chemistry, increased lymphokine-activated killer (LAK) cell activity, changes in mitogen responsiveness or alterations in the phenotypic profile of circulating lymphocytes. Nor were there any clinical changes associated with IL-2 therapy (e.g. depression, pyrexia, diarrhea). Animals that were treated with less than five doses of IL-2 also exhibited elevated immune responses, but they were not significantly different from untreated immunized controls. Interestingly, animals given five doses of IL-2 responded to minor contaminants present in the gIV preparation. This allows speculation that this dose regimen of IL-2 is not only a potent adjuvant for conventional vaccine immunizing doses, but will also allow the use of minute quantities of antigen for immunization.  相似文献   
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67.
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   

68.
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   
69.
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   
70.
There is a paucity of published information available on extrapulmonary cryptococcosis (EC) in children infected with human immunodeficiency virus, the etiologic agent of the acquired immunodeficiency syndrome. We surveyed investigators in pediatric acquired immunodeficiency syndrome around the country regarding their experience with EC. Investigators from 33 (87%) of 38 institutions responded and information on 13 patients from 11 institutions was analyzed. EC was the acquired immunodeficiency syndrome indicator disease in 9 (69%) of 13 patients. Median age was 8 years with a range of 2 to 17 years. Human immunodeficiency virus risk factors were transfusion (5 patients), hemophilia (4 patients) and perinatal exposure (4 patients). Meningitis, seen in 62% of patients, was the most common clinical manifestation. Although 2 patients with fulminant disease died before therapy was started, 10 (91%) of 11 had a clinical response to amphotericin B with or without flucytosine. Our study indicates a spectrum of EC in pediatric human immunodeficiency virus infection ranging from fulminant, fatal fungemia to chronic meningitis and fever of unknown origin. Cryptococcosis was generally not the cause of death in patients who initially responded to amphotericin B therapy. Optimal antifungal therapy, including the role of fluconazole, warrants further study.  相似文献   
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