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41.
The fatigue life of a welded aluminium T‐joint made from beams with rectangular hollow section (RHS) has been predicted using a crack propagation analysis and compared with experimental results from joints with different residual stress levels. To include the effect of the residual stresses, the stress ratio was calculated at the weld toe and, via Walker's equation, introduced into the analysis. How to obtain the Walker exponent has been discussed in detail. The introduction of a stress ratio at the weld toe provides good agreement between the experimentally and analytically found S–N curves. The effect of the residual stress was successfully included in the analysis.  相似文献   
42.
To determine the extent to which published randomized controlled trials (RCTs) of psychotherapy can be generalized to a sample of community outpatients, the authors used a method of matching information obtained from outpatient charts to inclusion and exclusion criteria from published RCT studies. They found that 80% of the patients in their sample who had diagnoses represented in the RCT literature were judged eligible for at least 1 published RCT; however, 58% of the patients had primary diagnoses such as adjustment disorder or dysthymia, which were not represented in the existing psychotherapy outcome literature. The most common reasons that patients in their sample did not match with published RCTs for psychotherapy are listed, and the implications of these findings for research and practice are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
43.
So called lethal midline granuloma is of great clinical and theoretical interest. Recent evidence has shown that most lethal midline granulomas are associated with a T-cell phenotype and they are therefore referred to as nasal T-cell lymphomas (NTCL). Immunohistochemical studies, however, have shown peculiar phenotypic features such as expression of natural killer (NK)-cell-related markers and extensive T-cell antigen loss including absence of expression of alpha beta T-cell receptor (TCR). In this study, we reported genotypic and immunohistochemical features in two cases of lethal midline granuloma. The histopathological diagnosis of the biopsy specimens was polymorphic reticulosis/midline malignant reticulosis. Both cases displayed a CD2+, CD3-, CD3 epsilon+, CD4-, CD8-, CD16-, CD56+ phenotype, suggesting that these tumors may be peripheral T-cell lymphomas with extensive loss of T-cell antigens and expression of NK cell antigen (CD56), or, alternatively, NK cell neoplasias. No TCR beta gene rearrangement was detected in these cases. Monoclonal Epstein-Barr virus (EBV) genome was detected in each specimen by Southern blot hybridization. The tumor cells in one of the two cases expressed latent membrane protein (LMP). These findings support the concept that lethal midline granuloma constitutes a distinct group of lymphomas that, in addition to their peculiar clinical features, exhibits the phenotype of extensive loss of T-cell antigens and expression of the NK cell antigen, as well as harbors the EBV. In view of the LMP-transforming potential, these data suggest that EBV may play a role in the pathogenesis of lethal midline granuloma.  相似文献   
44.
Reexpansion pulmonary edema is a rare complication attending the rapid reexpansion of a chronically collapsed lung, such as occurs after evacuation of a large amount of air or fluid from the pleural space. The condition usually appears unexpectedly and dramatically-immediately or within 1 h in 64% of patients and within 24 h in the remainder. The clinical manifestations are varied; they range from roentgenographic findings alone in asymptomatic patients to severe cardiorespiratory insufficiency. The radiographic evidence of reexpansion pulmonary edema is a unilateral alveolar filling pattern, seen within a few hours of reexpansion of the lung. The edema may progress for 24-48 h and persist for 4-5 days. Human data on the pathophysiology of reexpansion pulmonary edema derive from small series of patients, case reports, and reviews of the literature. On the other hand, a larger body of data exists on experimental reexpansion pulmonary edema in cats, monkeys, rabbits, sheep, and goats. This review examines the clinical and experimental evidence for reexpansion pulmonary edema. In addition, we detail the historical background, clinical setting, treatment, and outcome of reexpansion pulmonary edema.  相似文献   
45.
Developing retinal axons must follow a stereotypic course directing them to the subcortical visual centres which on arrival they must recognise. Transplantation studies suggest that local substrate cues close to the surface of the brainstem and diffusible factors emanating from the target region are important. To test a role for diffusible factors, we transplanted retinae to the cerebral cortex and have shown that outgrowth can be promoted by BDNF secreting fibroblasts.  相似文献   
46.
OBJECTIVE: To assess the plasma levels and action of arginine vasopressin (AVP) in patients with Cushing's disease. There are many reports that patients with Addison's disease have increased AVP levels associated with hyponatraemia and hypoosmolality, but none on the dynamics of secretion of this neurohormone during osmolality-based stimulation in patients with chronic hypercortisolism. DESIGN AND SUBJECTS: The plasma AVP concentration and the urinary and plasma osmolality after a 7.5-h water deprivation test (WDT) were evaluated in 13 patients with Cushing's disease and 15 normal (control) individuals. In patients with Cushing's disease we also assessed the urinary osmolality in response to 10 micrograms i.v. desmopressin (DDAVP) administered at the end of the WDT. RESULTS: At the end of the WDT, urinary osmolality was significantly lower in patients with Cushing's disease (511.5 +/- 148.5 mOsm/l) than in the normal subjects (981.1 +/- 107.1 mOsm/l, P < 0.001), whereas plasma osmolality did not differ between the two groups. Consequently, the urine/plasma osmolality ratio (Uosm/Posm) was lower in patients with Cushing's disease than in normal individuals (1.8 +/- 0.5 compared with 3.4 +/- 0.4, P < 0.001). The AVP concentration also was greater (7.3 +/- 3.1 pmol/l) in those with Cushing's disease than in the controls (3.9 +/- 2.3 pmol/l, P < 0.005). After administration of DDAVP to the hypercortisolaemic patients, the urinary osmolality attained (718.0 +/- 200.0 mOsm/l) was still lower than that in the normal group at the end of WDT (P < 0.005). CONCLUSIONS: Patients with Cushing's disease presented higher AVP levels and smaller Uosm/Posm ratios than normal subjects. After DDAVP, the patients with Cushing's disease were unable to concentrate the urine adequately. These data suggest that the kidney shows resistance to the action of both endogenous and exogenous AVP in patients with Cushing's disease.  相似文献   
47.
The technique of renal time ultrasound of the scrotum is described. The examination was performed in 50 patients and 15 normal males at the Sahinbey Hospital. Given the clinical diagnosis ultrasound proved reliable in almost all cases. In this study ultrasonography of the scrotum has been found to be the most useful method demonstrating testicular diseases.  相似文献   
48.
The extent of adverse health effects of isocyanates when combined with other chemicals is not well documented. This study was conducted as a 2.5-year follow-up as well as to determine daily and weekly effects of exposure to isocyanates and organic solvents on pulmonary function. The concentrations of chemicals sampled were below the recommended exposure criteria. No daily or weekly reduction in the subjects' pulmonary function was observed. The isocyanate/solvent-exposed subjects showed significant long-term reduction in their forced vital capacity (P < 0.05) and expiratory volume in 1 second (P < 0.001). No such changes were observed in non-exposed subjects or in those exposed only to organic solvents. The proportion of subjects who developed respiratory symptoms in the isocyanate-exposed group was not significantly greater than that of the non-exposed group. The results of this study indicate that long-term exposure to isocyanates, even in very low concentrations, may contribute to impaired pulmonary function.  相似文献   
49.
We examined the effects and safety of deep brain stimulation (DBS) as a treatment for essential tremor (ET). Ten ET patients with disabling medication-refractory tremor underwent stereotactic implantation of a DBS lead in the left Vim thalamic nucleus and completed a 6-month follow-up. The Clinical Tremor Rating Scale and disability assessments were performed at baseline, 1-, 3-, and 6-month follow-up. There were significant improvements in dressing, drinking, eating, bathing, and handwriting as reported by the subjects. Tremor severity, writing, pouring, and spiral and line drawing were significantly improved as rated by the examiner. Improvements persisted through the 6-month follow-up period. Although global disability significantly lessened in the group as a whole, one subject with hand-finger tremor accentuated by writing had no change in disability status. In this 6-month open-label study, DBS was effective and safe in reducing tremor and functional disability in ET.  相似文献   
50.
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