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21.
1. The kidney bean lectin, phytohaemagglutinin (PHA), induced a marked atrophy of skeletal muscle which was evident from the changes in tissue composition (protein, RNA, DNA and polyamine content) and from the reduction in weight and protein synthesis of hind leg muscles of rats fed on kidney bean-diets for four days. The beta-adrenoceptor agonist, clenbuterol, induced skeletal muscle hypertrophy by transiently stimulating protein synthesis. As a consequence, the muscle loss caused by a short exposure to PHA was, in part, ameliorated by clenbuterol treatment. 2. Cardiac muscle was affected to a lesser extent than skeletal muscle by both clenbuterol and the lectin. However, there was evidence that protein synthesis in heart was reduced by PHA. 3. PHA had opposite effects on the gut, the lectin-induced hyperplasia of the jejunum was accompanied by a large increase in protein synthesis. Clenbuterol alone had no effect on the jejunum whereas a combination of PHA and clenbuterol appeared to exacerbate the effect of the lectin on gut. 4. Both the lectin-induced gut growth and the hypertrophy of skeletal muscle caused by clenbuterol were preceded by the accumulation of polyamines in the respective tissues. Of particular note was the observation that a significant increase in the proportion of the intraperitoneally injected 14C-labelled spermidine or putrescine taken up by the growing tissues could be detected by the second day. Therefore, the measurement of uptake of labelled polyamines may be used as a sensitive indicator of early alterations in tissue metabolism.  相似文献   
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This study provides an overview of the papers emanating from the experimental trial that evaluated a new cognitive rehabilitation program in older adults who were experiencing normal cognitive decline. The main features of the design are summarized, along with evidence that the training produced long-lasting improvement in memory performance, goal management, and psychosocial status. The benefits were attributed to several factors, including the program's emphasis on techniques that promoted efficient strategic processing. Limitations of the program and directions for future research are discussed.  相似文献   
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To evaluate the utility of the polymerase chain reaction (PCR) for documenting herpes simplex virus (HSV) in persons with reactivated genital lesions viral isolation was compared with a recently developed PCR method. Three women experiencing four episodes of recurrent genital herpes were followed for 10 days per episode with daily examination and duplicate swabs of the lesions, one for HSV culture and one for PCR. HSV type 2 was cultured from three of four episodes and the mean duration of viral isolation from recurrent genital lesions was 2.6 days. PCR detected HSV DNA from lesion swabs during all four episodes, and HSV DNA was positive for an average of 6.8 days. HSV DNA was demonstrated in ulcerative lesions on 15 of 17 days versus 3 of 17 days by viral isolation (P less than .01). HSV PCR became negative when the lesions reepithelialized. These data suggest that PCR is a more sensitive measure of HSV infection than routine viral culture and that PCR detects the presence of HSV at times when culture is negative.  相似文献   
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Insulin autoantibodies: their role in the pathogenesis of IDDM   总被引:2,自引:0,他引:2  
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The distal radioulnar joint plays an intricate part in the function of the wrist and thus in the function of the entire upper extremity. The radius and hand move in relation to and function about the distal ulna. Significant loads are transmitted to the forearm unit through the distal ulna via the triangular fibrocartilage complex. The anatomic relationships between the distal radius and ulna and ulnar carpus are precise, and even minor modification in these relationships leads to significant load changes and resultant pain syndromes. Evaluation of a patient with ulnar wrist pain is, at best, difficult. Despite a careful and thorough history and physical examination and the use of sophisticated ancillary diagnostic studies, some patients with distal radioulnar joint and ulnar carpal complex problems remain diagnostic and therapeutic mysteries. These patients are best followed; exploratory surgery is rarely satisfying to either the patient or the surgeon. Armed with an understanding of the normal anatomy and biomechanics, the examination of such a patient and subsequent treatment should become a challenge that is rewarding for both patient and treating physician.  相似文献   
29.
Melioidosis. Forgotten, but not gone!   总被引:3,自引:0,他引:3  
Melioidosis, infection by the soil bacterium Pseudomonas pseudomallei, has the potential for prolonged latency with recrudescence into an acute, often fulminating, and fatal infection. Although the organism is never found in North America, infection is endemic in areas of southeast Asia, and populations of service personnel exposed during the Vietnam war and southeast Asian immigrants are at risk of severe recrudescent disease. Diagnosis, however, has been missed or delayed because of lack of familiarity with this disease. We present a case of recrudescent melioidosis that illustrates the difficulties encountered in diagnosis and treatment. This case involves a 76-year-old Vietnam veteran who presented with melioidosis of the bone 18 years after exposure to the organism and 10 years after a missed diagnosis of latent pulmonary disease. This case illustrates the protean nature of latent infection and the difficulty of selecting successful antibiotic therapy.  相似文献   
30.
This review is intended to provide a balanced view of the role of surgical burn wound excision and closure within the larger context of the total care and rehabilitation of patients with burn injury. The historical background leading to present practice is outlined. The salient technical and logistical problems associated with the performance of wound excision are discussed, with emphasis on the necessity for expeditiously completing these procedures which are associated with major blood loss. A realistic analysis of the results of excisional therapy in patients with burns of varying severity is presented. Benefits attributable to the surgical phase of therapy become progressively more difficult to identify as the size of deep burns increases beyond 20% of total body surface area.
Resumen La presente revisión propone proveer una visión equilibrada del papel de la resección tangencial quirúrgica de la quemadura y su cierre en el contexto más amplio del cuidado total y la rehabilitación de pacientes con lesiones térmicas. Se hace un recuento de los antecedentes históricos y se discuten los más prominentes problemas técnicos y logísticos relacionados con la resección tangencial de la quemadura con énfasis en la necesidad de implementar en forma expedita estos procedimientos, los cuales se asocian con pérdidas mayores de sangre. Se presenta el análisis realista de los resultados de la resección tangencial en pacientes con quemaduras de gravedad variable. Los beneficios atribuibles a la fase quirúrgica de la terapia se hacen progresivamente más difíciles de identificar en cuanto la extensión y profundidad sobrepasan el 20% de la superficie corporal.

Résumé Cette article fait le point sur les avantages et inconvénients respectifs de l'excision et la suture dans le cadre du traitement et la rééducation des grands brûlés. L'historique de cette technique est résumée. Les principaux problèmes de technique et de logistique de l'excision des brûlures sont discutés, en soulignant la nécessité d'assurer un geste rapide enfin de réduire les pertes sanguines. Une analyse réaliste des résultats de la technique excisionnelle des brûlures de sévérité variable est présentée. Les bénéfices directement en rapport avec la chirurgie deviennent plus difficiles à apprécier lorsque la surface brûlée dépasse 20 % de la surface corporéelle.
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