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41.
Summary The purpose of the study was to analyse the effect of arm-shoulder fatigue on manual performance. Ten experienced carpenters performed three standardized tasks (nailing, sawing and screwing). Electromyographic activity was recorded from six arm-shoulder muscles and the performances were video-filmed. After 45 min of standardized arm-cranking (arm-shoulder-fatiguing exercise of approximately 70%–80% maximal oxygen consumption), the tasks were repeated. The number of work movements and the time taken for each task were recorded and the quality of the work performed was compared. After the fatiguing exercise, only nailing was perceived as being harder and more mistakes were made during nailing and sawing. Movement performance was not influenced during nailing but was slightly slower during sawing and faster during screwing. However, there were increased mean EMG amplitudes in the upper trapezius and biceps muscles during nailing, in the upper trapezius, anterior deltoid and infraspinatus muscles during sawing and in the anterior deltoid muscle during screwing. Of the muscles studied the upper trapezius and anterior deltoid muscles increased their activity most after the arm-shoulder-fatiguing exercise.  相似文献   
42.
BackgroundMost data on postoperative outcomes among patients with proximal extrahepatic cholangiocarcinoma are reported by single institutions. The purpose of this study was to analyze postoperative outcomes stratified by age and comorbidities.MethodsPatients with proximal extrahepatic cholangiocarcinoma who underwent a resection were identified in the National Cancer Database. Pathologic, postoperative, and survival outcomes were compared based on age and Charlson-Deyo comorbidity index.ResultsAmong the 1,579 patients, the average age was 66 years, and 9.4% of patients were older than 80 years. Most patients had a Charlson-Deyo score of 0 (72.4%), with the minority having scores of 1 (20.5%) or ≥2 (7.1%). Patients ≥80 years had a higher 90-day mortality rate compared with patients 65 to 79 and <65 years (21.3% vs 12.0% vs 7.4%, P < .001). Patients with a Charlson-Deyo score ≥2 had longer duration of stay, greater likelihood of requiring an unplanned readmission, and a higher 90-day mortality rate compared with patients with a lower comorbidity index. Median survival of patients <65, 65 to 79, and ≥80 years was 31, 24, and 17 months, respectively. A similar trend was seen with increasing Charlson-Deyo score (0: 27 months, 1: 25 months, ≥2: 20 months). On multivariable analysis, age ≥80 years (hazard ratio = 1.52, P = .01) and Charlson-Deyo score ≥2 (hazard ratio = 1.45, P = .01) were associated with poor survival.ConclusionIn patients with proximal extrahepatic cholangiocarcinoma, age ≥80 years and greater comorbidity index are associated with increased risk of 90-day mortality and poor overall survival. This suggests that resections in high-risk patient populations should be approached with caution.  相似文献   
43.
Zusammenfassung In Hirntumoren und tumorfreien Hirngeweben von Mensch und Kaninchen wurden verschiedene Phospholipoid-Fraktionen bestimmt. Die statistische Auswertung ergab für Tumoren eine signifikante Senkung aller absoluten Parameter. Der Quotient aus den nach alkalischer Hydrolyse erhaltenen cholinhaltigen und cholinfreien Fraktionen ist in den Hirntumoren signifikant erhöht. Unterschiede im Phospholipoidgehalt zwischen malignen und benignen Hirntumoren waren statistisch nicht erfaßbar.
Summary Various phospholipoid fractions were estimated in brain tumours an in normal human and rabbit brain tissue. A statistical evaluation showed a significant diminution of all absolute values in brain tumours. The ratio of choline-containing to choline-free fractions, measured after alkaline hydrolysis, is significantly higher in brain tumours. No statistically significant differences were noted in the phospholipoid contents of malignant and benign brain tumours.

Resumen En tumores cerebrales y en tejido cerebral no tumoral humano y de conejo se analizaron diversas fracciones de fosfolípidos. La valoración estadística dió por resultado, para los tumores, una disminución significante de todos los parámetros absolutos. El cociente de las fracciones conteniendo colina y libres de la misma, tras la hidrólisis alcalina, está significantemente aumentado en el caso de tumores cerebrales. Estadisticamente no se apreciaron diferencias entre el contenido de fosfolípidos en los tumores cerebrales malignos y benignos.

Résumé Les auteurs ont étudié la présence de différentes fractions phospholipidiques dans les tumeurs du cerveau et le tissu cérébral non tumoral de l'homme et du lapin. Les évaluations statistiques mettent en évidence pour les tumeurs une baisse significative de tous les paramètres absolus. La proportion entre les fractions contenant de la choline et les fractions n'en contenant pas, après hydrolyse alcaline, est augmentée de façon significative dans les tumeurs cérébrales. Par contre, une différence de teneur en phospholipides entre tumeurs malignes et tumeurs bénignes, n'a pu être statistiquement mise en évidence.

Riassunto Gli AA. hanno deterrninato le varie frazioni di fosfolipidi in tumori cerebrali ed in tessuti cerebrali esenti da tumori dell'uomo e del coniglio.L'elaborazione statistica dà per i tumori un significativo abbassamento di tutti i parametri assoluti. Il quoziente ricavato dalle frazioni a contenuto colinico e da quelle esenti da colina, in seguito ad idrolisi alcalina, risulta significativamente aumentato nei tumori.Non è stato possibile rilevare delle differenze statisticamente significative del contenuto di fosfolipidi tra tumori cerebrali maligni e benigni.


Herrn Dipl. Math.Günther Caroli möchten wir an dieser Stelle recht herzlich für seine Hilfe bei der statistischen Auswertung unserer Ergebnisse danken.  相似文献   
44.
Background: The highly swelling poly(glycerol monomethacrylate) gel (polyGLYMA) and hydrophilic polymer poly(triethylenglycol monomethacrylate (polyTEGMA) were tested as potential viscoelastics for intraopertive use in anterior segment surgery. Methods: PolyGLYMA was implanted into the anterior chamber in 5 rabbits, and 40% polyTEGMA in 16 rabbits. The eyes were enucleated 1 week to 3 months after the operation. The corneal endothelium was examined with specular microscopy, and then the whole eye histopathologically. Results: In all eyes of the polyGLYMA group, the clinical findings were characterized by a marked ciliary injection and severe secondary glaucoma, and the histologic ones by a marked inflammatory infiltration and thickening of Descemet's membrane in the anterior chamber angle. Specular microscopy revealed a decrease in the endothelial cell density and polymorphism of the endothelial cells. In the polyTEGMA group, the anterior segment and the fundus were physiologic all the time, and specular microscopy and histologic findings showed no degenerative and/or inflammatory changes. Conclusions: PolyGLYMA proved unsuitable for intracameral application in rabbits. The new polymer polyTEGMA is characterized by high biologic tolerance after its implantation into the anterior chamber of rabbits. PolyTEGMA 40% might be considered as a potential viscoelastic material in humans.  相似文献   
45.
Summary The purpose of the work reported here is to identify molecular components of the synaptic basal lamina of skeletal muscle fibres which allow recognition of original synaptic sites by regenerating motor axons. We focused on s-larninin and components recognized by the lectinDolichos biflorus agglutinin previously shown to be specifically located at the synaptic basal lamina. We used a cryoculture bioassay in which chick ciliary ganglion neurons grow on rat skeletal muscle cryostat sections. In control cultures, neurites extended over the muscle sections in close association with the muscle cell surface. It was observed that most of the neurites that extended towards the endplate zone and reached an area of 40 m around the neuromuscular junction ceased to grow when they contacted the synaptic site. Masking either lectin receptors or some s-laminin molecule epitopes prior to the culture of neurons alters the behaviour of growing neurites. On sections treated either withDolichos biflorus agglutinin or anti s-laminin monoclonal antibodies (D5 and C4) most of the neurites did not stop their growth at the synaptic regions. Moreover, treating muscle sections withDolichos biflorus agglutinin removed the gradient of substratum affinity around the endplate. These results indicate that the s-laminin andDolichos biflorus agglutinin receptors present on muscle cell surfaces may play a functional role in the interaction of growing neurites with original synaptic sites in the process of neuromuscular regeneration.  相似文献   
46.
47.
Summary We have recorded postural performance in 50 HIV-infected patients in different stages of the disease (Walter Reed (WR) stages I–VI) by means of a force measuring platform. The results were compared with 50 age-matched controls. A significant instability was particularly evident when standing on an unstable foot support. In patients standing with eyes closed, postural sway was significantly higher in every patient group (WR I–II:P<0.02, WR III–V:P<0.001, WR VI:P<0.001). Patients in stage WR I–II showed no relevant neurological abnormalities. In agreement with other neurophysiological data in the literature we suggest that postural imbalance could be an early sign of central nervous system penetration of HIV. No correlation with electromyographic or cerebrospinal fluid findings could be found.  相似文献   
48.
PURPOSE: To determine the safety, immunogenicity, and clinical response to an allogeneic tumor vaccine for non-small-cell lung cancer, we conducted a phase I trial in patients with advanced metastatic disease. PATIENTS AND METHODS: We treated 19 patients with a vaccine based on an adenocarcinoma line (AD100) transfected with B7.1 (CD80) and HLA A1 or A2. Patients were vaccinated intradermally with 5 x 10(7) cells once every 2 weeks. Three vaccinations represented one course of treatment. If patients had complete response, partial response, or stable disease, they continued with the vaccinations for up to three courses (nine vaccinations). Immune response was assessed by a change between pre-study and postvaccination enzyme-linked immunospot frequency of purified CD8 T-cells secreting interferon-gamma in response to in vitro challenge with AD100. RESULTS: Four patients experienced serious adverse events that were unrelated to vaccine. Another four patients experienced only minimal skin erythema. All but one patient had a measurable CD8 response after three immunizations. The immune response of six surviving, clinically responding patients shows that CD8 titers continue to be elevated up to 150 weeks, even after cessation of vaccination. Overall, one patient had a partial response, and five had stable disease. Median survival for all patients is 18 months (90% CI, 7 to 23 months), with corresponding estimates of 1-year, 2-year, and 3-year survival of 52%, 30%, and 30%, respectively. HLA matching of vaccine, age, sex, race, and pathology did not bear a significant relation to response. CONCLUSION: Minimal toxicity and good survival in this small population suggest clinical benefit from vaccination.  相似文献   
49.
We present the first use of tubeless superimposed combined high- and low-frequency jet ventilation (SHFJV) with a jet laryngoscope in laryngotracheal surgery in infants and children. Twenty-eight patients underwent 53 operative procedures. The average age of the patients was 7.3 years. The most common diagnoses were laryngeal papillomatosis and subglottic stenosis. The duration of jet ventilation averaged 33 min. The gas exchange was sufficient in each case. The advantages of SHFJV in the surgery of the laryngotracheal area in infants and children are optimal view at the larynx and trachea, maximum space for the handling, application of the laser without risks, no time limitation, suitability for stenosis, and neither anesthetic nor surgical complications.  相似文献   
50.
Tamoxifen, which is used for treating breast cancer, exhibits estrogenic and antiestrogenic characteristics, depending on the tissue. In the human breast it acts as an antiestrogen, whereas estrogenic effects have been reported on endometrium and bone. The purpose of this study was to determine whether tamoxifen (TAM) prevents bone loss in elderly, postmenopausal women. Bone mineral density of the lumbar spine (SBD) was measured in elderly women (at least 10 years after menopause) 5 years after stage I or II breast cancer (n=111). The results showed that SBD in untreated patients (n=74) was significantly lower (p0.05) than SBD in patients (n=37) treated with TAM over 5 years. In a subgroup of patients (n=24) with positive estrogen receptor status, changes in SBD 12 months after discontinuation of 5-year TAM therapy were measured and compared with the changes of extended TAM treatment over a sixth year. Twelve months after withdrawal of 5-year TAM medication (n  相似文献   
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