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561.
This case discusses an elderly female who presented acutely with compromised profunda femoris pseudoaneurysm and massive haematoma five weeks after dynamic hip screw insertion for a left neck of femur fracture. The only precipitating factor leading to this presentation was ongoing physiotherapy. She was referred from a rehabilitation hospital to the nearest vascular surgical unit for acute and definitive surgical intervention. Post-operatively, she fared incredibly well, regaining her baseline level of functioning. History taking is complex in a patient with dementia. Clinical examination should follow with a focused approach to the site of recent operation and also where complications are likely to manifest when an alteration from baseline cognitive function is noted. This is of course in addition to the complete work up required from a holistic perspective with any acute deterioration. Imaging should be arranged and prompt referral made if a treatable acute cause is identified. It is imperative to involve family and/or next of kin if possible, but this should not impede prompt decision-making in the patient’s best interests by the clinical team if delays are likely to occur.  相似文献   
562.
The pathogenetic mechanism of vasculitis in systemic lupus erythematosus (SLE) remains a subject of debate. Evidence for a direct pathogenetic role of anti-double-stranded DNA antibodies (anti-dsDNA) is not strong. Supernatant concentrations of interleukin-1β and interleukin-6, and mRNAs encoding for interleukin-1 α and interleukin-1 receptor-1 were determined in cultured human umbilical vein endothelial cells (HUVEC), incubated with control IgG ( n =18), anti-dsDNA ( n =18), or IgG from the same lupus patient depleted of anti-dsDNA by affinity chromatography (anti-dsDNA-dep-IgG). Compared with control IgG, there was a significant increase of supernatant interleukin-1β and interleukin-1α mRNA in endothelial cells incubated with anti-dsDNA. The supernatant interleukin-1β and interleukin-6, and mRNAs encoding for interleukin-1α and interleukin-1 receptor-1, were significantly elevated in endothelial cells incubated with anti-dsDNA, compared with those incubated with anti-dsDNA-dep-IgG. Pretreating HUVEC with native DNA before incubating with anti-dsDNA did not result in an additive effect. These in vitro studies suggest that anti-dsDNA plays an important pathogenetic role in inducing inflammatory injury of vascular endothelium in SLE.  相似文献   
563.
This prospective study was undertaken to evaluate the incidence and significance of chronotropic incompetence in 211 patients [age 71.1 6 10.6 years (mean 6 SD)] by means of maximum exercise test in order to determine the indication for rate-responsive pacing before primary pacemaker implantation (147 patients) or pacemaker replacement (64 patients). There were 112 (53%) patients with second- or third-degree AV block, 63 (30%) with sick sinus syndrome, and 36 (17%) with chronic atrial fibrillation. Chronotropic incompetence was defined as maximum heart rate lower than age-adjusted norm calculated by the formula: 0.7x(220 - age) and its significance as the difference between the two rates. The overall incidence of chronotropic incompetence was 42%. The incidence was significantly higher in patients with atrial fibrillation (67%, P<0.0005) and sick sinus syndrome (49%, P<0.012) than in those with AV block (30%). The mean difference between maximum heart rate and the age-adjusted norm was 18% (range 2%-63%). The mean difference was significantly higher in patients with atrial fibrillation (27%, range 8-63%) than in those with sick sinus syndrome (19%, range 2%-45%, P<0.01), or with AV block (12%, range 6%-26%, P<0.000001). The rate-responsive pacemakers were implanted in 44% of 211 patients studied and in 43% of 196 patients excluded from the study due to the apparent (contra)indication of rate-responsive pacing (NS). Thus, chronotropic incompetence seems to be common in the pacemaker patient population. The highest incidence and significance was found in patients with chronic atrial fibrillation. Systematic evaluation of chronotropic competence can double the rate of implantation of rate-responsive pacemakers; however, further studies are needed to clarify relation between the significance of chronotropic incompetence and functional benefit of rate-responsive pacing.  相似文献   
564.
Neonatal Group B Streptococcal bacteraemia in India: ten years'experience   总被引:3,自引:0,他引:3  
Group B Streptococcus (GBS) is an infrequent cause of neonatal septicaemia in many developing countries. In a perinatal centre in India with 60,119 live births between 1988 and 1997, GBS was isolated from blood cultures of 10 babies. Thus the incidence of GBS bacteraemia was 0.17 per 1000 live births. Lethargy, respiratory distress and poor perfusion were the presenting features in eight symptomatic babies. Two babies had meningitis, three required ventilatory support and one died. There were no cases of late onset disease. The low incidence could be due to the low rate of colonisation and high prevalence of protective antibody in the mothers.  相似文献   
565.
医学物理学教育的现状与思考   总被引:22,自引:7,他引:22  
随着医院对医学物理学人才需求的增加,医学物理学人才的培养变得更加重要。由于各种原因,我国的医学物理学教育,特别是肿瘤放射治疗及医学影像等临床领域中医学物理工作者的培养与国外先进水平相比有很大的差距,本文在介绍国内外医学物理学教育状况的基础上,简要介绍了AAPM制定的《医学物理学硕士学位的教学计划》,对如何发展国内医学物理学教育提出一些思考。  相似文献   
566.
Objective To observe the time course of changes in synaptophysin (P38) expression in the cortex and hippocampus of rats with posttraumatic epilepsy (PTE), and explore the role of synaptic plasticity in the epileptogenesis of PTE. Methods Thirty-seven male Sprague-Dawley rats were randomized into normal control group (n=5), sham-operated group (n=12) with intracortical saline injection, and PTE model group (n=20) with stereotactic FeCl<,2> injection (0.1 mol/L, 10 μ1) into the motor cortex. The expression of P38 in the brain cortex and hippocampus of the rats was detected immunohistochemically at 1 h and 7, 14 and 30 days after the injections. Results Most of the rats with FeCl<,2> injection developed isolated epileptiform discharges soon alter the injection. Compared with the sham-operated groups, the rats in PTE group showed significantly decreased P38 expression in the right frontal cortex at all the time points of measurement (P<0.05). At 1 h after FeCl<,2> injection, P38 expression in the polymorphic layer, stratum lacunosum and stratum radiatum of the right hippocampai CA3 area and DG molecular layer underwent no significant changes (P>05), but at 7 days, the expression increased significantly in all the stratum regions of the right hippocampal CA3 area, and this high expression level was maintained till 30 days after the injection. Conclusion Synaptic plasticity alterations in relation to P38 expression changes in the cortex and hippocampus may play an important role in the epileptogenesis of PTE in this rat model.  相似文献   
567.
568.
Manipulation of CT data for temporal-bone imaging   总被引:1,自引:0,他引:1  
Shaffer  KA; Volz  DJ; Haughton  VM 《Radiology》1980,137(3):825
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569.
Wilner  HI; Lazo  A; Metes  JJ; Beil  KA; Nowack  P; Jacobs  J 《Radiology》1987,163(3):759-762
Cataclysmal hemorrhage occurred in eight patients with known aggressive squamous cell tumors of the head and neck. Angiography showed neovascularity, narrowing, beading of affected arteries, and pseudoaneurysms. Postembolization residual stump formation was seen in a few patients. A total of 11 embolization procedures were performed in these eight patients. Embolization materials included polyvinyl alcohol, isobutyl-2-cyanoacrylate, and detachable balloons. Survival times ranged from 5 to 274 days, with no deaths as a direct result of hemorrhage. Only one severe complication following embolization was noted.  相似文献   
570.
Thrombin generation in acute promyelocytic leukemia   总被引:3,自引:0,他引:3  
Bauer  KA; Rosenberg  RD 《Blood》1984,64(4):791-796
Six patients with disseminated intravascular coagulation (DIC) in association with acute promyelocytic leukemia (APL) were studied with sensitive radioimmunoassays that are able to quantitate the extent of thrombin generation within the human circulation. The levels of prothrombin activation fragment, F1 + 2, and thrombin-antithrombin complex (TAT) were obtained at clinical presentation and were then followed serially in several patients during induction chemotherapy. The antileukemic therapy often resulted in a rise in the plasma levels of these molecular species. Simultaneous measurements of fibrinopeptide A (FPA) were also obtained, and the concentrations of this polypeptide were correlated with the levels of F1 + 2 and TAT in patients who were not receiving heparin. Nine individuals with other morphological subtypes of acute nonlymphocytic leukemia (ANLL) were investigated and were usually found to have increased levels of F1 + 2, TAT, and FPA at clinical presentation. However, the magnitude of the elevations was considerably greater and the correlation between TAT and FPA levels was stronger in APL than in ANLL. These studies provide direct evidence that patients with APL, as well as ANLL, generate excessive amounts of thrombin within their vascular system. Furthermore, the data suggest that the concentrations of F1 + 2, compared with the levels of FPA, may be a more sensitive indicator of hemostatic system hyperactivity in individuals with DIC.  相似文献   
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