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21.
The focus on quality of life issues in wound care has justly taken a far greater importance. With the acceptance that pain can be a major factor to the patient, and in particular, pain at dressing change comes the opportunity for avoidance and/or reduction strategies. Whilst pain has been associated with wound infection for millennia, it is only much more recently that this has received due attention from research and clinical practice. In this study, the nature of pain, changes in pain and pain associated with infection are the focal points. A Delphi approach, now a frequently used tool in wound care research, has been used to obtain expert opinion on these aspects of management.  相似文献   
22.
Background: Advantages of cross‐pin retained implant supported restorations (ISRs) include predictable retrieval and predictable retention. Unlike direct to fixture (DTF) or cement retained restorations, the prosthetic design of a cross‐pinned restoration retains gaps at the interfaces between the crown, abutment and cross‐pin screw. These spaces permit leakage into the suprastructure and gasket placement has been recommended to prevent this leakage. Methods: Five different gaskets were assessed for their ability to prevent leakage into a cross‐pinned ISR. The gaskets tested were: cement admixture on the cross‐pin screw; cement admixture on the inner surface of the coping and the cross‐pin screw; cement admixture on the inner surface of the coping only; cement admixture placed 1 mm from the margin of the coping and a filler placed in the abutment chimney. Results: Only gaskets which sealed both the cross‐pin screw interface and the abutment‐crown interface prevented leakage. A filler placed in the abutment chimney prevented leakage into this space but did not prevent fluid accumulating between the coping and abutment. Conservative placement of cement at the margin of the coping failed to prevent leakage. Conclusions: Cement gaskets may effectively prevent leakage into a cross‐pinned ISR. However, the use of a cement as a gasket has to be weighed against the issue of predictable retrieval, cement extrusion and incomplete seating.  相似文献   
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Chronic orofacial pain of neuropathic origin can present diagnostic and management dilemmas to dental practitioners and also affects the patient's quality of life. Intracranial aneurysms are a potential cause of stroke (e.g. sub‐arachnoid haemorrhage) that is usually associated with, high rates of mortality and morbidity. A patient who had been previously managed for symptoms of temporomandibular joint disorder (TMD) presented with sharp, shooting pain of moderate intensity. It was precipitated by swallowing, and radiated to the right throat, posterior border of the mandible, ear and temporomandibular joint. Clinical and radiological investigations ruled out odontogenic pain, TMD and other more common types of facial pain. Magnetic resonance imaging revealed a 7 × 6 mm aneurysm in the right middle cerebral artery (MCA) which was subsequently surgically clipped. Interestingly, the facial pain resolved after this procedure. Compression of the insular region of the brain innervated by the trigeminal, glossopharyngeal and vagus nerves provides a plausible explanation for the pain reported. To our knowledge, this is the first case of facial neuralgia associated with an aneurysm in the MCA which emphasizes the importance of a multidisciplinary approach in the diagnosis and management of unusual cases of chronic orofacial pain.  相似文献   
25.
Lesions of the articular surfaces of the knee have been managed by various techniques over the last 50 years. Surgical management has involved: excising the damaged area, refashioning the underlying bone to produce a fibrous response, and introducing allograft, autograft and synthetic materials to encourage a repair matrix. The techniques and their pitfalls are reviewed and discussed, and suggestions made as to the direction of future studies for the repair of osteochondral lesions in the painful knee.  相似文献   
26.
Dunn  EK; Macchia  RJ; Solomon  NA 《Radiology》1981,139(1):175-180
The testicular scintigraphic findings of nine patients with surgically and pathologically proved torsion of the testis of over 24 hours duration are reviewed. In the delayed blood-pool images each showed the classical avascular twisted testicle with a variable peripheral rim of hyperemia. In the dynamic blood-flow phase, eight revealed a perceptible increase of vascular perfusion in the scrotal region on the affected side, in addition to the testicular radionuclide angiogram peculiarities previously described for missed testicular torsion. This pattern of perfusion was seen only in torsion of over one day duration. A low salvage probability is expected in these cases.  相似文献   
27.
Evolutionary silencing of the human elastase I gene (ELA1)   总被引:6,自引:0,他引:6  
  相似文献   
28.
Competitive control of the self-renewing T cell repertoire   总被引:1,自引:0,他引:1  
We develop a mathematical model for the self-renewing part of the T cell repertoire. Assuming that self-renewing T cells have to be stimulated by immunogenic MHC-peptide complexes presented on the surfaces of antigen-presenting cells, we derive a model of T cell growth in which competition for MHC-peptide complexes limits T cell clone sizes and regulates the total number of self-renewing T cells in the animal. We show that for a sufficient diversity and/or degree of cross-reactivity, the total T cell number hardly depends upon the diversity of the T cell repertoire or the diversity of the set of presented peptides. Conversely, for repertoires of lower diversity and/or cross-reactivity, steady-state total T cell numbers may be limited by the diversity of the T cells. This provides a possible explanation for the limited repertoire expansion in some, but not all, mouse T cell re-constitution experiments. We suggest that the competitive interactions described by our model underlie the normal T cells numbers observed in transgenic mice, germ-free mice and various knockout mice.   相似文献   
29.
It was shown recently that mutations of the ATRX gene give rise to a severe, X-linked form of syndromal mental retardation associated with alpha thalassaemia (ATR-X syndrome). In this study, we have characterised the full-length cDNA and predicted structure of the ATRX protein. Comparative analysis shows that it is an entirely new member of the SNF2 subgroup of a superfamily of proteins with similar ATPase and helicase domains. ATRX probably acts as a regulator of gene expression. Definition of its genomic structure enabled us to identify four novel splicing defects by screening 52 affected individuals. Correlation between these and previously identified mutations with variations in the ATR-X phenotype provides insights into the pathophysiology of this disease and the normal role of the ATRX protein in vivo.   相似文献   
30.
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