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51.
52.
The normal development of tibial torsion   总被引:2,自引:1,他引:2  
Objective: Pathological rotation of the leg is a well-known problem in paediatric orthopaedics. In this study the normal development of tibial torsion during growth was evaluated by computed tomography (CT). Design: Seventy-eight normal individuals (52 children, 26 adults) aged 3–51 years were examined with CT. In axial scans the angle between a line tangential to the posterior part of the femoral condyles and the intermalleolar line, a line through the centre of the lateral and medial malleolus, was measured. The radiation exposure was evaluated and accepted by The National Department for Radiation and the Regional Committee for Ethics in Science. Results: CT showed that the average lateral torsion of the leg at the age of 4 years was 28° with an individual variation of 20°–37°. Later the increase in tibial torsion was on average 1°/year until 10 years of age and, thereafter, 4° until maturity when the mean lateral torsion was 38° (18°–47°). Conclusion: Tibial torsion in children mainly develops during the first 4 years of life. After this the increase was of less clinical significance. Received: 13 November 2000 Revision requested: 26 February 2001 Revision received: 19 March 2001 Accepted: 18 April 2001  相似文献   
53.

Objective

There is a close relation between cartilage health and its hydration state. Current magnetic resonance methods allow visualizing this tissue. However, a quantitative analysis is more useful when studying disease. The purpose of this study was to quantify water content in cartilage using magnetic resonance without contrast agents.

Materials and methods

Water-content estimations using T1 magnetic resonance mapping were done first in eight gelatin samples where the water content was previously known. The same method was used in the physeal areas of eight skeletally immature 30-kg pigs. To calculate accuracy, T1 calculations were compared to dry-freeze, which is considered the gold standard because it can remove the total water content form a tissue. Four fresh cartilage and seven gelatin samples were dry-frozen. Water content obtained from dry-freeze was compared to the one calculated from T1 map values. A mathematical model and statistical analysis were used to calculate the predictive value of the method and its significance.

Results

T1-map-based magnetic resonance method can calculate water content in cartilage with an accuracy of 97.3 %. We calculated a coefficient of variance for this method against dry-frozen sample of 3.68 (SD?=?1.2) in gelatin samples, and 2.73 (SD?=?1.3) in in vivo samples. Between two independent observers, the coefficient of variance was 0.053, which suggests it can be easily reproduced.

Conclusions

Magnetic resonance was able to calculate, with high accuracy, the cartilage water content using T1 mapping sequences.  相似文献   
54.
We lengthened 9 tibial segments over a nail to reduce the time in the external fixator in 5 patients with constitutional shortness. The median lengthening was 7 (5.5-7.3) cm and the external Ilizarov frame was removed after median 99 (63-125) days. In spite of a short time in the external fixator, consolidation was slow, with a median lengthening index of 4.4 (2.4-6.1) months/cm. The procedure resulted in 3 fatigue fractures of the intramedullary nail or interlocking screws that needed revision and bone grafting. In 1 patient, a deep intramedullary infection occurred. After the experience of these major complications we have returned to the traditional callotasis lengthening method described by Ilizarov.  相似文献   
55.

Background  

An influenza pandemic may have considerable impact on health and societal functioning. The aim of this study was to explore people's reflections on the consequences of a pandemic.  相似文献   
56.
Primary malignant melanoma of the cervix was diagnosed in a patient presenting with postmenopausal bleeding. A cervical lesion was biopsied, and diagnosis was established by electron microscopy and staining procedures. After failing radiotherapy, the patient was treated with simple hysterectomy and bilateral salpingo-oophorectomy. The cytology, histology, and electron microscopy of this lesion are presented in addition to a clinical discussion.  相似文献   
57.
OBJECTIVE: To estimate the effect from an osteoporosis intervention in terms of postponement of hip fractures. DESIGN: A Markov model using Nordic data on mortality and hip fracture incidence. PATIENTS: Women aged 50 years and older with increased risk of hip fracture. INTERVENTION: A hypothetical intervention that reduces the risk of hip fracture by 50%. MAIN OUTCOME MEASURES: Postponement of hip fractures--that is increase in expected fracture-free survival from osteoporosis interventions. RESULTS: A 1-year treatment would on average postpone hip fracture by 12 days if therapy were started at the age of 50 years and 23, 55, 90 or 74 days if the treatment were started at the ages of 60, 70, 80 or 90 years, respectively. For 10 years of treatment, the benefit was 146, 260, 369, 373 and 167 days, respectively. The younger the patient, the lower the risk of fracture and, consequently, the greater the benefit for those few who actually could benefit. CONCLUSIONS: The benefit in terms of average postponement of hip fractures from osteoporosis intervention was, other things being equal, greatest in women aged 70-90 years. Fracture postponement may represent an alternative to risk reductions in expressing the effect of osteoporosis interventions.  相似文献   
58.
Treatment failures are common in patients infected with metronidazole-resistant Helicobacter pylori in the gastric mucosa when triple therapy including metronidazole is used. In patients with treatment failure and metronidazole-resistant H. pylori, a higher eradication rate for H. pylori was found after secondary treatment with bismuth/ranitidine in combination with antibiotics including metronidazole, compared with the same antibiotics combined with a standard dose of omeprazole. This agrees with our previous finding that bismuth was able to reduce the susceptibility of H. pylori to metronidazole. In this study, we have found that nizatidine, an H(2)-receptor antagonist, is also able to reduce the susceptibility of H. pylori to metronidazole in vitro, despite having no direct inhibitory effect on the growth of H. pylori. This agrees with earlier findings that compounds having the ability to reverse antibiotic resistance do not necessarily have an antibiotic or chemotherapeutic effect in the sense of growth inhibition. Therefore, it was decided to investigate the effect of nizatidine and omeprazole on the oxidative respiratory chain, as it is known that metronidazole is able to inhibit the activity of fumarate reductase of H. pylori. This enzyme is a key enzyme in the alternative respiratory chain under anaerobic conditions. Nizatidine was, in these preliminary experiments, found to inhibit fumarate reductase in a dose-dependent way, like metronidazole, whereas omeprazole had almost no effect on fumarate reductase. No other significant effects on the enzymes of the respiratory chain were found. The synergistic effect of nizatidine on metronidazole resistant H. pylori strains could be explained by the effect on fumarate reductase, whereas the effect of omeprazole is different and could be an inhibition of a proton pump in H. pylori. Reversal of antimicrobial resistance with the help of different non-antibiotics seems to be possible by using quite different compounds, and is therefore to be explained by different molecular mechanisms.  相似文献   
59.

Background  

Endoscopic colorectal cancer (CRC) screening is currently implemented in many countries. Since endoscopes cannot be sterilised, the transmission of infectious agents through endoscopes has been a matter of concern. We report on a continuous quality control programme in a large-scale randomised controlled trial on flexible sigmoidoscopy screening of an average-risk population. Continuously, throughout a two-year screening period, series of microbiological samples were taken from cleaned ready-to-use endoscopes and cultured for bacterial growth.  相似文献   
60.
Kristiansen IS  Nexøe J  Gyrd-Hansen D  Nielsen JB 《Family practice》2002,19(5):566; author reply 566-566; author reply 567
In a recent editorial, Misselbrook and Armstrong comment uponthe concept of risk in relation to John Everyman1 and claimthat the number needed to treat (NNT) for Mr Everyman is 11.It is  相似文献   
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