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991.
Long-term effects (104 weeks) of 2 extremes of gap size on the mechanical behavior of the rabbit medial collateral ligament were examined. In the midsubstance of each right medial collateral ligament, either an 8 mm gap injury was created or a 4 mm Z plasty injury was created and repaired. Each group was subdivided into a healing interval of 40, 78, or 104 weeks. Femur-medial collateral ligament-tibia complexes were tested mechanically or examined with light microscopy. Both injuries healed with histologically similar tissue and showed improved mechanical behavior 78 weeks after injury. No further improvement was measurable 104 weeks after injury. Scar material properties remained markedly inferior to normal regardless of injury. Low load and viscoelastic behavior recovered relatively well regardless of gap size. However, gap injuries showed significantly inferior structural properties at all intervals. These results suggest that a large initial gap between ligament ends in the extraarticular space predisposes scars to long term structural weakness. If this principle is true clinically, then patients with large gaps between torn ligament ends (caused by displacement, folding, or retraction) may function well at lower loads, but they may be chronically at greater risk of reinjury at high loads. 相似文献
992.
Today more than 71% of children with cancer are surviving their disease. This is because of improved treatment including aggressive combination therapy and better supportive care measures. The majority of patients with bone tumors are now being treated with surgery, chemotherapy, and radiation therapy, resulting in an increase in numbers of long-term survivors. This aggressive therapy, however, has increased the risk of developing late effects. This article reviews some of these late effects in survivors of bone tumors diagnosed in childhood or adolescence. Areas that are explored include cardiac, infections, second operations, second malignant neoplasms, renal, auditory, fertility, pulmonary, functional, and psychosocial outcomes. The need for long-term follow-up clinics is also addressed. 相似文献
993.
Urothelial tumors are common: their diagnosis and long-term management represent a large part of most urologists' workload. The majority of such tumors are 'superficial' and are mostly managed by repeated cystoscopic surveillance and treatment. A smaller but significant group of patients either start with, or subsequently progress to, more invasive disease, thus requiring an alternative and more invasive treatment. Maximizing the benefit/risk ratio of the diagnosis and the various treatment options of bladder tumors requires the availability of a reliable tumor marker. The concept of tumor markers encompasses the utilization of any detectable deviation from normality that is indicative of neoplasia. For bladder cancer, most of these markers are present in urine. In this part of the review we examine, from the clinician's point of view, the literature verdict on older techniques such as cytology and cytometry, as well as the current status of new nucleus-based tests such as P53, telomerase, NMP22 and Ki67. 相似文献
994.
BJ DeBaun 《Canadian Metallurgical Quarterly》1998,33(4):671-684
A surgical site infection in an orthopedic surgery is a dreaded and often catastrophic complication. This article provides an overview of the incidence, pathogenesis, financial impact, as well as a discussion of patient and operation-related risk factors for orthopedic surgical site infections. The reader is provided insight into infection control interventions intended to minimize surgical site infections in orthopedic patients. Some of these practices are evidence-based and others exist only because of theoretical benefit. 相似文献
995.
996.
Classical congenital adrenal hyperplasia (CAH) results from an inherited enzymatic defect in cortisol synthesis and more than 90 per cent of cases are due to 21-hydroxylase deficiency. The androgen excess associated with this condition typically results in ambiguous external genitalia in affected females. It has been shown that prenatal treatment with dexamethasone is successful in preventing or reducing genital ambiguity in affected females. Rather than treating with dexamethasone, some couples choose to terminate the pregnancy when an affected fetus is prenatally diagnosed. We report a female with classical CAH who was born with normal external genitalia, although maternal treatment with dexamethasone did not begin until 16 weeks' gestation. 相似文献
997.
BJ Landrum 《Canadian Metallurgical Quarterly》1998,25(5):227-232
A mathematical model for the prothrombin time test is proposed. The time course of clotting factor activation during coagulation was calculated, and the sensitivity of the test to a decrease in the concentrations of coagulation proteins or their activities was studied. The model predicts that only severe coagulation disorders connected with a more than five-fold decrease in the concentrations or activities of the blood coagulation factors can be revealed by the test. 相似文献
998.
999.
BJ Amuzu 《Canadian Metallurgical Quarterly》1998,41(3):702-711
Many nonsurgical treatments for incontinence are available and all offer benefit to some patients. Patients with mild to moderate incontinence usually benefit the most from these modalities and, for many, it may obviate the need for surgery. Several factors influence the success of nonsurgical treatments for incontinence. Most important is the patient's motivation and ability to comply with the therapy. Selection of therapy appropriate for a given patient is, therefore, important. Compliance is better when the patient has a better understanding of the therapy and expected results. When appropriate, combinations of therapy may be very useful. 相似文献
1000.
M Ala-Korpela KK Changani Y Hiltunen JD Bell BJ Fuller DJ Bryant SD Taylor-Robinson BR Davidson 《Canadian Metallurgical Quarterly》1997,38(5):840-844
Quantitative artificial neural network analysis for 1550 ex vivo 31P nuclear magnetic resonance spectra from hypothermically reperfused pig livers was assessed. These spectra show wide ranges of metabolite concentrations and have been analyzed using metabolite prior knowledge based lineshape fitting analysis which had proved robust in its biochemical interpretation. This finding provided a good opportunity to assess the performance of artificial neural network analysis in a biochemically complex situation. The results showed high correlations (0.865 < or = R < or = 0.992) between the lineshape fitting and artificial neural network analysis for the metabolite values, and the artificial neural network analysis was able to fully represent the trends in the metabolic fluctuations during the experiments. 相似文献