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61.
The calcar femorale in cemented stem fixation in total hip arthroplasty   总被引:2,自引:0,他引:2  
The calcar femorale is a vertical plate of bone lying deep to the lesser trochanter and is formed as a result of traction of the iliopsoas which separates the femoral cortex into two distinct layers, the calcar femorale and the medial femoral cortex. They fuse together proximally to form the medial femoral neck. A stem placed centrally will abut against the calcar femorale with little or no space for cement. Clearing of the calcar will offer space for a cement layer, which will support the stem proximally on the posterior aspect. We compared two consecutive groups of Charnley low-friction arthroplasties, with and without clearing of the calcar. In 330 patients who had an arthroplasty without clearing the calcar, there were ten revisions for aseptic loosening of the stem and six other stems were considered 'definitely loose', giving a rate of failure of 4.8%. In 111 patients in whom the calcar was cleared there was only one revision for aseptic loosening and no stems were classed as 'definitely loose', giving a rate of failure of 0.9%. Survivorship analysis has again shown the need for long-term follow-up; the differences became clear after ten years but because of the relatively small numbers, statistical analysis is not yet applicable. We now clear the calcar femorale routinely and advocate optimal access to the medullary canal and insertion of the stem in the area of the piriform fossa.  相似文献   
62.
Fleming AN  Smith PJ 《Hand Clinics》2000,16(4):609-624
The diagnosis of vascular cell tumors of the upper limb in children can be extremely difficult. There is considerable variation in their presentation and natural history. In most instances, the correct diagnosis can be achieved after a careful history and examination. Almost invariably, they are benign lesions and, of these, hemangiomas and vascular malformations account for more than 90%. Worrying tumors of the intermediate and malignant grade are rare. Any atypical, rapidly growing tumor with superficial ulceration and bony destruction on radiology should be regarded as malignant. Histologic differentiation of all problematic vascular swellings requires the services of an experienced pediatric vascular pathologist. In the future, specific cellular marker profiles of individual lesions may simplify the diagnosis. Conservative, symptomatic management is the first line of treatment for almost every vascular swelling. Intervention is reserved for swellings complicated by ulceration, uncontrollable rapid growth, coagulopathies, cardiovascular compromise, or the possibility of malignancy. Small lesions may generally be simply excised, whereas larger lesions often remain a problem.  相似文献   
63.
AIMS: To define outcome measures for auditing the clinical care of children and adolescents with insulin dependent diabetes mellitus (IDDM) and to assess the benefit of appointing a dedicated paediatric trained diabetes specialist nurse (PDSN). METHODS: Retrospective analysis of medical notes and hospital records. Glycaemic control, growth, weight gain, microvascular complications, school absence, and the proportion of children undergoing an annual clinical review and diabetes education session were assessed. The effect of the appointment of a PDSN on the frequency of hospital admission, length of inpatient stay, and outpatient attendance was evaluated. RESULTS: Children with IDDM were of normal height and grew well for three years after diagnosis, but grew suboptimally thereafter. Weight gain was above average every year after diagnosis. Glycaemic control was poor at all ages with only 16% of children having an acceptable glycated haemoglobin. Eighty five per cent of patients underwent a formal annual clinical review, of whom 16% had background retinopathy and 20% microalbuminuria in one or more samples. After appointing the PDSN the median length of hospital stay for newly diagnosed patients decreased from five days to one day, with 10 of 24 children not admitted. None of the latter was admitted during the next year. There was no evidence of the PDSN affecting the frequency of readmission or length of stay of children with established IDDM. Non-attendance at the outpatient clinic was reduced from a median of 19 to 10%. CONCLUSIONS: Outcome measures for evaluating the care of children with IDDM can be defined and evaluated. Specialist nursing support markedly reduces the length of hospital stay of newly diagnosed patients without sacrificing the quality of care.  相似文献   
64.
This report highlights the association between tuberous sclerosis and Wolff-Parkinson-White syndrome. Ten patients with concurrent diagnoses of Wolff-Parkinson-White syndrome and tuberous sclerosis were identified. Wolff-Parkinson-White syndrome presented early in life, nine cases being diagnosed in the first year. Eight of the 10 cases were male. In eight cases, the syndrome was associated with supraventricular tachycardias, and in nine with cardiac rhabdomyomata. One child died from cardiac failure secondary to obstruction of the left ventricular outflow tract by a rhabdomyoma. Five of nine survivors showed resolution of Wolff-Parkinson-White syndrome on follow up. The accessory pathway was localised in nine patients from surface electrocardiograms: six children had left sided pathways and three had right sided pathways.  相似文献   
65.
Severe preeclampsia rarely occurs prior to 20 weeks of gestation except in pregnancies with triploidy. The patient reported herein is a 29-year-old primigravida who developed severe preeclampsia at 20 weeks of gestation. Evaluation of the pregnancy demonstrated a markedly abnormal quadruple screen. Amniocentesis demonstrated a fetus with triploidy, despite a normal appearance.  相似文献   
66.
Cytochrome P450 epoxygenases as EDHF synthase(s)   总被引:2,自引:0,他引:2  
The metabolism of arachidonic acid by cytochrome P450 (CYP) epoxygenases generates epoxyeicosatrienoic acids (EETs) which affect numerous cellular process including Ca(2+) signaling and the activity of Ca(2+)-dependent K(+) channels. The expression of the CYP epoxygenase(s) that generate EETs in endothelial cells is not constitutive but is determined by a number of physical (fluid shear stress and cyclic stretch) and pharmacological stimuli which also affect responses attributed to an endothelium-derived hyperpolarizing factor (EDHF). This review summarizes the role played by EETs, and the enzymes that generate and metabolize them, in EDHF-mediated responses.  相似文献   
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BackgroundRecent evidence has demonstrated that athletes are at greater risk for a lower extremity injury following a return-to-sport (RTS) after sport-related concussion (SRC). The reason for this is not completely clear, but it has been hypothesized that persistent deficits in neurocognitive factors may be a contributing factor.Hypothesis/PurposeThis study assessed simple reaction time, processing speed, attention, and concentration in a group of athletes, post-concussion upon clearance for RTS for potential deficits that may result in slower reaction time, processing speed, attention, and concentration. The researchers hypothesized that the concussion group would demonstrate worse scores on both assessments compared to a sex-, age-, and sport-matched cohort.Study DesignCase-controlled studyMethodsTwelve participants who had suffered a SRC and eight healthy individuals who were matched to the concussed group by age, sex, and sport were evaluated. Those with a concussion had been cleared for RTS by a licensed healthcare provider. Each participant underwent neurocognitive tests that included a simple reaction time test (SRT) and the King-Devick Test (K-D). Independent t-tests were performed to compare the groups with significance set a priori at p<0.05.ResultsThere was a significant difference (p =0.024) between groups for SRT with the concussed group demonstrating a better SRT than the control group. There were no significant differences (p =0.939) between the groups for the K-D.ConclusionWith no significant differences between groups in the K-D assessment and, surprisingly, the concussed group having a better SRT compared to the healthy group, our hypothesis was not supported.Clinical RelevanceThese specific measures, compounded with extensive post-concussion time lapse until RTS clearance, may have limited capacity in revealing potential persistent deficits in relevant neurocognitive characteristics.Level of EvidenceLevel of Evidence 3  相似文献   
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