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51.
This paper reports the occurrence of a rare, yet distinct pituitary adenoma which was surgically removed from a 42-year-old male with both clinical and biochemical evidence of acromegaly and mild hyperprolactinaemia. The monomorphic adenoma consisted of mature cells which were ultrastructurally indistinguishable from those of a prolactinoma. Electron immunocytochemistry, including a series of double-labelling techniques using selected colloidal gold particles as markers, indicated the presence of a pituitary adenoma in which the cells were capable of simultaneously producing growth hormone and prolactin and packaging them within the same secretory granule. This is thought to represent a mammosomatotroph cell adenoma.  相似文献   
52.
Herpesvirus saimiri (HSV) is a T-lymphotropic tumor virus that causes fulminant lymphomas and leukemias in various New World primates other than its natural host, the squirrel monkey (Saimiri sciureus). In the course of completing the nucleotide sequence of its genome, we identified an open reading frame of 363 nucleotides, designated HVS-15, that has no detectable homology to any other viral sequences to date. HVS-15 encodes a 121-amino-acid protein which shows significant similarities to human CD59, a phosphatidyl-inositol-glycan-anchored glycoprotein involved in T-cell activation and restriction of complement-mediated lysis. The predicted HVS-15 gene product is more similar to human CD59 than to the related murine Ly-6 antigens. A nucleotide sequence identity of 64% was found between HVS-15 and the CD59 reading frame, and a 48% identity exists between the corresponding protein sequences. The comparison of the amino acid sequences revealed a number of conserved structural features such as a similar pattern of hydrophobic termini and an identical cysteine skeleton.  相似文献   
53.
The purpose of this study was to compare estimates of body composition in two ethnic groups, 31 black and 38 white girls 10 through 16 years of age, to establish accurate and precise laboratory standards for field measures of body composition in the NHLBI Growth and Health Study HC 55025. The dual energy X-ray absorptiometry (DXA) measures of fat free mass (FFM) and % body fat (%BF) were made using Hologic QDR-1000/W. Corresponding values of FFM and %BF from underwater weighing (UWW) were determined using the two-component model of Siri, and these were corrected using the model of Lohman for white girls only. In the comparison of the different models and methods, the two-component model overestimated FFM compared to estimates from DXA for black girls, as did the corrected Lohman model for white girls. The two-component model significantly overestimated %BF in both white and black girls compared to corresponding estimates from DXA. The ratio of bone mineral content (BMC)/FFM affected the degree of %BF differences in black girls but not in white girls. Also, as the density of FFM increased or approached adult status in black girls (BMC/FFM increased), differences between the two-component model and estimates from DXA decreased. In both groups of girls, the relationship of %BF from UWW and DXA are a function of the level of body fatness. DXA values of %BF are greater than those from UWW under about 24% body fat, but the converse occurs above 25% body fat. The inability of UWW using the two-component model to account for the body composition in these girls can be corrected in part by measuring the variables for a multicomponent model or more easily by using DXA estimates of body composition. © 1994 Wiley-Liss, Inc.  相似文献   
54.
Progress in the development of a system to provide sensory feedback of the pinch force of an artificial hand is described. Design criteria relating to electrocutaneous stimulation and compatibility with myoelectric control are discussed. Details of a practical system, presently in use by two amputees prior to full-scale clinical evaluation, are presented.  相似文献   
55.
56.
Surgical palliation of unresectable carcinoma of the pancreas   总被引:6,自引:0,他引:6  
The results of palliative surgery for pancreatic carcinoma were reviewed in over 10,000 patients from the English-language literature from 1965 to 1983. This collected series suggests that biliary-enteric bypass relieves the sequelae of chronic extrahepatic biliary obstruction, prolongs survival, and provides symptomatic palliation. The more easily constructed loop cholecystojejunostomy is preferred over choledochojejunostomy unless malignant obstruction of the cystic duct is imminent. Chronic percutaneous internal biliary drainage offers reasonable palliation in the poor-risk patient who is not a candidate for surgery. Routine concomitant gastroenterostomy is recommended in all patients with a reasonable life expectancy since operative mortality is unaffected, and the incidence of future duodenal obstruction is at least 16%. Intraoperative chemical splanchnicectomy is easily performed and appears beneficial in relief of pain related to advanced pancreatic carcinoma.
Resumen Se revisaron los resultados de la cirugía paliativa para carcinoma pancreático en más de 10.000 pacientes de la literatura inglesa desde 1965 hasta 1983. Esta serie colectiva sugiere que la derivación bilio-entérica alivia las secuelas de la obstrucción biliar extrahepática crónica, prolonga la supervivencia y provee paliación sintomática. Se prefiere la colecisto-yeyunostomía, que es la de más fácil realización, a menos que la obstrucción neoplásica del canal cístico sea inminente. El drenaje biliar percutáneo crónico ofrece una paliación razonable en el paciente de alto riesgo que no sea candidato para cirugía. Se recomienda la gastroenterostomía concomitante como rutina en todos los pacientes con una razonable expectativa de vida, puesto que la mortalidad operatoria no resulta afectada y la incidencia de futura obstrucción duodenal es de no menos de 16%. La esplacnicectomía química intraoperatoria es fácilmente realizable y es beneficiosa en el alivio del dolor asociado con el carcinoma pancreático avanzado.

Résumé Les résultats de la chirurgie palliative pour cancer du pancréas ont été étudiés dans la littérature anglaise de 1965 à 1983. Ils concernent 10.000 malades et permettent de suggérer que les interventions de dérivation assurent la disparition des symptômes de la rétention biliaire et l'allongement du temps de survie.La simple cholécystojéjunostomie est préférable à la cholédocojéjunostomie dès lors que le canal cystique n'est pas envahi. Le drainage percutané et transhépatique apporte une solution au problème de la rétention biliaire chez le malade en mauvais état général et incapable de subir une intervention chirurgicale. La gastro-entérostomie associée est recommandée chez tous les malades dont l'espoir de vie est de durée raisonnable car la mortalité n'est pas augmentée et le taux d'obstruction duodénale atteint 16%. La splanchnicectomie chimique au cours de l'intervention est facile à pratiquer et permet d'atténuer la douleur en cas de cancer avancé.
  相似文献   
57.
BackgroundWork-related musculoskeletal injuries have been increasingly recognized to affect surgeons. It is unknown whether such injuries also affect surgical trainees. The purpose of this study was to assess the ergonomic risk of surgical trainees as compared with that of experienced surgeons.MethodsErgonomic data were recorded from 9 surgeons and 11 trainees. Biomechanical loads during surgery were assessed using motion tracking sensors and electromyography sensors. Demanding and static positions of the trunk, neck, right/left shoulder, as well as activity from the deltoid and trapezius muscles bilaterally were recorded. In addition, participants reported their perceived discomfort on validated questionnaires.ResultsA total of 87 laparoscopic general surgery cases (48 attendings and 39 trainees) were observed. Both trainees and attendings spent a similarly high percentage of each case in static (>60%) and demanding positions (>5%). Even though residents reported overall more discomfort, all participants shared similar ergonomic risk with the exception of trainees’ trunk being more static (odds ratio: –11.42, P = .006).ConclusionSurgeons are prone to ergonomic risk. Trainees are exposed to similar postural ergonomic risk as surgeons but report more discomfort and, given that musculoskeletal injuries are cumulative over time, the focus should be on interventions to reduce ergonomic risk in the operating room.  相似文献   
58.
59.
This paper explores the potential contribution of timebanking, an innovative volunteering scheme, to the co-production of preventive social care with adults in England. Interest in volunteering in social care has increased as one proposed solution to the international crisis of a rising demand for services in juxtaposition with decreased resources. Volunteering has been particularly promoted in preventive services that prevent or delay care needs arising. Despite sustained interest in volunteering and co-production in social care, little is known about how theory translates into practice. Reporting implementation data from a Realistic Evaluation of six case studies in England, this paper explores one volunteering scheme, timebanking. The research explores how timebanks were working, what contribution they can make to adult social care, and whether they are an example of co-production. Data collected included interviews, focus groups or open question responses on surveys from 84 timebank members, and semi-structured interviews with 13 timebank staff. Each timebank was visited at least twice, and all timebank activity was analysed for a period of 12 months. Data were triangulated to improve reliability. The research found that in practice, timebanks were not working as described in theory, there were small numbers of person-to-person exchanges and some timebanks had abandoned this exchange model. Timebanks faced significant implementation challenges including managing risk and safeguarding and the associated bureaucracy, a paternalistic professional culture and the complexity of the timebank mechanism which required adequate resources. Lessons for timebanks are identified, as well as transferable lessons about co-production and volunteering in social care if such schemes are to be successful in the future.  相似文献   
60.
Changes in sensory-cognitive input: effects on cerebral blood flow   总被引:1,自引:0,他引:1  
Eight healthy right-handed young men were subjected to local CBF measurement by [15O]water and positron emission tomography during partial sensory deprivation and during sensory-cognitive activation; physiological, hormonal, and subjective stress measurements were also performed. Results indicated that (a) "whole-brain" CBF increased during activation; (b) the greatest increase in CBF was in the primary visual cortex; (c) differences between hemispheres were not observed, but CBF was greater anteriorly than posteriorly in the deprivation condition only; (d) within-subject variability of CBF was not influenced by the sensory-cognitive condition; and (e) the procedure was not stressful.  相似文献   
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