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11.
In a world of computer-manipulated pictures easier than ever to achieve, many photographers and artists are called upon to combine images from various sources for illustrative purposes such as 'web pages', advertisements, public relations brochures, etc. To achieve an accurate interpretation in a finished composite illustration made up of photographs manipulated using a computer (or using conventional methods) the illustrator must be aware of the design and compositional elements of each image incorporated in the final illustration. Design and composition elements include: lighting direction and shadow, density, colour balance, etc. Yet another design and composition element too often overlooked is depth cues. Depth cues are the means by which the viewer perceives depth in a two-dimensional image, in this case: a photograph. This paper describes and illustrates the known depth cues contained in the photographic image.  相似文献   
12.
In order to define the state of adaptive transportation equipment, wheelchair users with spinal cord injury (SCI) and equipment vendors were surveyed about equipment, funding, maintenance, and repair. SCI registries from two states, Virginia and Arkansas, were used to create the sample pool of users and 225 responses were received. A list of equipment vendors and vehicle modifiers was compiled from several national resources, and 123 responses were received from 36 states. User respondents were generally satisfied with their adaptive equipment, which typically required only minor inexpensive (<$100) repairs, if any. Personal or family money was used by over 90% of the respondents for equipment funding. Vendors reported that a substantial amount of custom modification or fabrication of equipment is required to meet the needs of their clients. Lifts, external controls, and six-way power seats were cited by vendors as the equipment requiring the most frequent repair. The survey results provide an examination of the opinions and experiences of users and vendors of adaptive transportation equipment, which should prove useful to those involved in evaluating equipment, equipment availability, and the need for industry-wide standards.  相似文献   
13.
STUDY DESIGN: A preintervention and postintervention, repeated-measures experimental design. OBJECTIVES: To investigate the immediate effect of low-Dye taping on peak and mean plantar pressures during gait in subjects with navicular drop exceeding 10 mm. BACKGROUND: Low-Dye taping is commonly used to support the longitudinal and transverse arches of the foot in an attempt to reduce the effects of symptoms associated with excessive pronation. Plantar pressure measurement has been used as an indirect indicator of pronation during gait. METHOD AND MEASURES: The right foot of 60 subjects was tested using the Emed-AT system to obtain plantar pressure values. Subjects performed 6 barefoot walks over the Emed pressure platform while taped and a further 6 walks while untaped. Plantar pressures were recorded. Each footprint obtained was divided into 10 sections or 'masks.' Average peak and mean plantar pressure values (N/cm2) were calculated for both taped and untaped walks for each mask. RESULTS: Paired t tests demonstrated significant changes in peak plantar pressure in 8 of the 10 areas of the foot and significant changes in mean plantar pressure in 9 of the 10 areas of the foot. Low-Dye taping significantly decreased pressure under the heel and the medial and middle forefoot, while increasing pressure under the lateral midfoot and under the toes. A significant decrease in mean plantar pressure was observed under the lateral forefoot, while no significant difference was demonstrated in peak plantar pressure under this area. The area under the medial midfoot demonstrated no significant change in either peak or mean pressure. CONCLUSIONS: Low-Dye taping significantly altered peak and mean plantar pressure values in subjects with navicular drop exceeding 10 mm. In particular, peak and mean plantar pressure increased under the lateral midfoot and under the toes, and decreased under the heel and forefoot, suggesting that a decrease in the amount of pronation occurred.  相似文献   
14.
Presacral tumors are rare,but can comprise a great variety of histological types.Congenital tumors are the most common.Once the diagnosis is established,surgical resection is essential because of the potential for malignancy or infection.Previous biopsy is not necessary or may be even harmful.To decide the best surgical approach(abdominal,sacral or combined) an individual and multidisciplinary analysis must be carried out.We report three cases of cystic presacral masses in which a posterior approach(Kraske procedure) enabled complete resection,the only way to decrease local recurrence.All patients had a satisfactory recovery.A brief overview of retrorectal tumors is presented,focusing on classification,clinical presentation,diagnosis and surgical management.  相似文献   
15.
16.
BACKGROUND: There is a paucity of information about the impact of upper extremity (UE) injuries on patient outcomes, particularly after major trauma. METHODS: Data were obtained from a statewide trauma registry. Cases were defined as major trauma cases (Injury Severity Score > 15) with (UE group) and without (no-UE group) an associated upper extremity injury. Multivariate analysis was performed to identify independent predictors of outcome. RESULTS: Major trauma patients with UE injury were 1.5 times (p = 0.011) more likely than the no-UE group to have a length of stay greater than 7 days. After adjusting for age, mechanism of injury, and Injury Severity Score, UE injury was not an independent predictor of discharge destination. CONCLUSION: In major trauma patients, the presence of an upper extremity injury is a significant predictor of length of stay, indicating a greater complexity and cost of care associated with this group of major trauma patients.  相似文献   
17.

Introduction

Traumatic brain injury (TBI) is the single largest cause of death and disability following injury worldwide. While TBI in older adults is less common, it still contributes to significant morbidity and mortality in this group. Understanding the patient characteristics that result in good and poor outcome after TBI is important in the clinical management and prognosis of older adult TBI patients. This population-based study investigated predictors of mortality and longer term functional outcomes following serious TBI in older adults.

Methods

All older adults (aged > 64 years), isolated moderate to severe TBI cases from the population-based Victorian State Trauma Registry for the period July 2005 to June 2007 (inclusive) were extracted for analysis. Demographic, injury event, injury diagnosis, management and comorbid status information were obtained and the outcomes of interest were in-hospital mortality, and the Glasgow Outcome Scale-Extended (GOS-E) score at 6 months post-injury. Multivariate logistic regression analyses were used to identify independent predictors of in-hospital mortality and independent living (GOS-E > 4) status at 6 months.

Results

Of the 428 isolated, older adult TBI cases, the majority were the result of a fall (88%), male (55%), and aged > 74 years (76%). The in-hospital death rate was 28% and increasing age (p = 0.009), decreasing GCS (p < 0.001) and injury type (p = 0.002) were significant independent predictors of in-hospital mortality. Of the 310 patients who survived to discharge, 65% were successfully followed-up 6 months following injury. There was no difference between patients lost to follow-up and those successfully followed-up with respect to the key population indicators of age, gender, or head injury severity. Younger (<75 years) patients, and those with an SBP on arrival at hospital of 131-150 mmHg, were at increased odds of living independently at follow-up. No patients with a GCS < 9 had a good 6-month outcome, and most of them died. The survival rate for brainstem injury was also low (21%).

Conclusion

In this population-based study, we found that age, GCS, brainstem injury, and systolic blood pressure were the most important factors in predicting outcome in older adults with an isolated moderate to severe TBI.  相似文献   
18.

Objective

Negative pressure therapy (VAC, vacuum assisted closure) is a method used still in our country. It consists of a system of aspirating a wound by means of a piece of foam and a few adhesive films. It allows the treatment of complex wounds, included (although this is still controversial) those with intestinal fistulas. We present 3 cases of treatment with VAC in this situation and a review of the published literature.

Patients and method

We have treated 10 patients, since VAC therapy was introduced into our centre of which 3 of whom had a fistula in the bed of the surgical wound. We describe the clinical information of the patients and the therapy that followed in each of the cases.

Results

Significant local clinical improvement of the disease, with control of the symptoms, was achieved in all 3 cases. We were able to re-operate to close the fistula in one of the patients, with subsequent good progression of the wound. In the other two cases it gave them a better quality of life although both died due to the overall complexity of their situation.

Conclusions

VAC therapy, although controversial in the treatment of intestinal fistulas, can help to improve the local situation of the wounds, the comfort of the patients and their general situation.  相似文献   
19.
The severe diabetic nephropathy that develops in the hypertensive transgenic (mRen-2)27 rat with streptozotocin (STZ) diabetes has previously been considered angiotensin II-dependent. Because metabolic pathways are also activated in the diabetic kidney, the present study aimed to determine whether renoprotection could be afforded with inhibitors of advanced glycation end products (AGEs), ALT-946, and aminoguanidine (AG). At 6 weeks of age, nondiabetic control and STZ diabetic Ren-2 rats were randomized to receive vehicle, ALT-946 (1 g/l), or AG (1 g/l) and were studied for 12 weeks. Systolic blood pressure was unchanged with diabetes, ALT-946, or AG. Both kidney weight and glomerular filtration rate were increased with diabetes and unchanged with ALT-946 or AG. ALT-946 and AG equally ameliorated glomerulosclerosis and medullary pathology; however, ALT-946 did reduce cortical tubular degeneration to a greater extent than AG. Albumin excretion rate, which was elevated with diabetes, was reduced with ALT-946 but not AG. AGE immunolabeling was increased in glomeruli and reduced with ALT-946 and AG. These findings indicate that even in the context of renal injury presumed to be primarily blood pressure- and/or angiotensin II-dependent, approaches that interfere with metabolic pathways such as inhibitors of AGE formation can confer renal protection in experimental diabetes.  相似文献   
20.
This study reviewed the 18-year experience of acute dialysis in the pediatric intensive care unit, in order to identify factors that could predict outcome, and to determine whether newer modalities of acute dialysis have influenced this outcome. Sixty-six children (ages 1 day to 19 years) received acute dialysis from May 1980 to April 1998. Factors predicting outcome were analyzed using univariate and Cox regression analysis. Modality of dialysis in the first 15 years was exclusively peritoneal dialysis, with a mortality of 63.9%. However, in the last 3 years, with increasing patient numbers, continuous hemodiafiltration (CHDF) was the modality of choice (56.7%), with a mortality of 73.3%. Univariate analysis showed that age <1 year, coma, acute tubular necrosis, disseminated intravascular coagulopathy, assisted ventilation, and hypotension were associated significantly with poor outcome (P<0.05). Cox regression analysis revealed that mortality was significantly higher in patients on mechanical ventilation (RR 5.96, 95% CI 1.82–19.50), or with age <1 year (RR 2.00, 95% CI 1.08–3.73). In conclusion, despite the increasing use of CHDF over the last 3 years, there was no significant improvement in mortality, probably related to the fact that more critically ill patients were dialyzed. Received: 21 March 2000 / Revised: 12 October 2000 / Accepted: 19 October 2000  相似文献   
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