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991.
Since the second half of the XX century a steady evolution of hip prosthesis design is taking place. Implant shape, fixation systems and materials are constantly evolving. The paper presents the materials combinations most commonly used in hip prosthesis (metal-metal, metal-polyethylene and ceramic). All the above mentioned materials have been in used for over 25 years, and thanks to minor modification and better quality are widely used all over the world. The authors basing on biochemical studies, clinical observations and personal experience present problems related to materials used in hip prosthesis.  相似文献   
992.
The nonunion of the lateral humeral condyle is the most important complication in course of the treatment of the fractures lateral humeral condyle. The cause of the occurrence is the articular liquid penetration to the fracture site, minor blood supply of the fractured fragment based only on the vessels penetrating from the metaphysis, insufficient immobilization period and fragment relocation. The operative treatment of a condyle nonunion previously was performed cautiously because of the high risk of the condyle necrosis and the mild nature of the deformity. The elbow with nonunion condyle is usefull and satisfactory even after bringing increasing valgus deformity and a high risk of the ulnar nerve neuropathy into consideration. A 7-YEAR-old boy with a condyle nonunion was treated operationaly. Operative procedure shouldn,t be prolonged for more than a year after the trauma because of the increased deformity and condyle remodelling. A Tahdjian technique was used. The operation focused on an intraarticular approach with an olecranon ostotomy for the avoidance of the vessels penetrating from the condyle metaphysis. After debridgement and cortical grafts filling of the nonunion site a Kirschner fixation combined with olecranon wire loop fixation were performed. Satisfactory results were achieved in a form of fragments union within six weeks of the surgery and the total range of motion of the elbow joint within 6 months of the operation. During the treatment no signs of the neurovascular complications were observed.  相似文献   
993.
994.
Cellularity in different regions of adipose tissue in young men and women   总被引:1,自引:0,他引:1  
Body cell mass, body fat, and total number of fat cells were determined in young men and women. In addition, regional determinations of adipose tissue thickness, fat cell size, and fat cell number were also performed. The individuals studied were 11 male and 12 female medical students with a mean age of 22 yr. In order to avoid deviations from ideal body weights, the individuals were preselected by using anthropometric standards. The women had more body fat than the men, which was due to an increase in the total number of fat cells. Mean fat cell size did not differ significantly between sexes. The women had greater adipose tissue thickness than the men, which was primarily due to an increase in local fat cell number in all regions investigated (epigastric, hypogastric, femoral, and gluteal) except in the gluteal region, where the difference was mainly explained by larger fat cells in women. When expressed in per cent of maximum values, the intrasexual patterns of adipose tissue thickness and local fat cell number in different regions were similar in men and women, while the pattern concerning fat cell size was slightly different between the sexes. There were no differences between sexes in cholesterol, triglyceride, fasting blood sugar, or fasting insulin values. Middle-aged randomly selected men and women examined previously had a larger amount of body fat than the young men and women, respectively, examined in the present investigation. This difference in body fat with age was due to a larger mean fat cell size in the middle-aged populations, while there was no difference in total fat cell number.  相似文献   
995.
996.
Members of a group of substituted 9-benzyladenines have been identified as effective inhibitors of inflammatory aspects of the delayed hypersensitivity skin reaction in the guinea-pig. Inhibitory activity was demonstrable in the efferent arc of the cell-mediated tuberculin and contact dermatitis (2,4-dinitrochlorobenzene) reactions. One of the compounds, 2-amino-9-benzyladenine, inhibited both turpentine-induced and histamine-induced inflammation in the skin. The toxicity and inhibitory activities of some of these compounds are discussed, and reference is made to the structurally related mercaptopurines.  相似文献   
997.
Eight severely obese patients with adipose tissue hypercellularity, elevated body cell mass, and a juvenile onset of obesity were subjected to physical training during 6 mo without dietary restrictions. The training program was of 35-min duration three times weekly and followed a fixed schedule individualized to the working ability of each subject, so that the heart rate was 10–15 beats below maximal during three 5-min periods of each training session. Body weight, body cell mass, and body fat showed no significant changes after 3 or 6 mo of training. Fasting plasma insulin decreased after 3 mo of training, but fasting blood glucose was not changed. After 6 mo plasma insulin values were still decreased. Now glucose tolerance had also improved, and plasma triglycerides showed a trend to lower values. The results suggest that the lack of body fat decrease after the long training period might be characteristic for subjects with the type of severe obesity studied, because in a previous study1 a similar, although lighter, training procedure produced a marked body fat decrease in patients without severe obesity.  相似文献   
998.
Female rats were given progesterone in a high and a low dose or insulin by injection. Both hormones caused hyperinsulinemia and an elevated body weight, explainable by increased fat tissue weight, which in turn was due to an increased fat cell size. There was a regional specificity of these effects for both procedures. It was therefore concluded that adipose tissue does not react as a homogenous tissue to different stimuli. Although not definitely conclusive because of difference in the degree of hyperinsulinemia the results also indicate that the effects of insulin are primarily exerted on the small fat cells of the subcutaneous region while progesterone increased the size of the larger parametrial fat cells.  相似文献   
999.
1000.
Long-stay patients in the pediatric intensive care unit   总被引:8,自引:0,他引:8  
OBJECTIVE: Length of stay in the pediatric intensive care unit (PICU) is a reflection of patient severity of illness and health status, as well as PICU quality and performance. We determined the clinical profiles and relative resource use of long-stay patients (LSPs) and developed a prediction model to identify LSPs for early quality and cost saving interventions. DESIGN: Nonconcurrent cohort study. SETTING: A total of 16 randomly selected PICUs and 16 volunteer PICUs. PATIENTS: A total of 11,165 consecutive admissions to the 32 PICUs. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: LSPs were defined as patients having a length of stay greater than the 95th percentile (>12 days). Logistic regression analysis was used to determine which clinical characteristics, available within the first 24 hrs after admission, were associated with LSPs and to create a predictive algorithm. Overall, LSPs were 4.7% of the population but represented 36.1% of the days of care. Multivariate analysis indicated that the following factors are predictive of long stays: age <12 months, previous ICU admission, emergency admission, no CPR before admission, admission from another ICU or intermediate care unit, chronic care requirements (total parenteral nutrition and tracheostomy), specific diagnoses including acquired cardiac disease, pneumonia, and other respiratory disorders, having never been discharged from the hospital, need for ventilatory support or an intracranial catheter, and a Pediatric Risk of Mortality III score between 10 and 33. The performance of the prediction algorithm in both the training and validation samples for identifying LSPs was good for both discrimination (area under the receiver operating characteristics curve of 0.83 and 0.85, respectively), and calibration (goodness of fit, p = .33 and p = .16, respectively). LSPs comprised from 2.1% to 8.1% of individual ICU patients and occupied from 15.2% to 57.8% of individual ICU bed days. CONCLUSIONS: LSPs have less favorable outcomes and use more resources than non-LSPs. The clinical profile of LSPs includes those who are younger and those that require chronic care devices. A predictive algorithm could help identify patients at high risk of prolonged stays appropriate for specific interventions.  相似文献   
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