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991.
992.
Recurrent dislocation of the patella and the Goldthwait operation   总被引:1,自引:0,他引:1  
In this study 17 patients with recurrent dislocation of the patella were followed up 10 years after their Goldthwait operation. The subjective and clinical findings were excellent or good in 70%. X-radiographs indicated osteoarthritis of the femoropatellar joint in 60%. Concerning the aetiopathological factors, we found an increased external torsion of the afflicted extremity (measured by computed tomography).  相似文献   
993.
A H Kassan  R Lalloo  G Kariem 《SADJ》2000,55(7):359-363
This study analysed the prevalence, demography, soft- and hard-tissue injury patterns, management and complications of gunshot injuries to the maxillo-facial region in 301 patients treated at Groote Schuur Hospital, Cape Town. The number of patients presenting with maxillo-facial injuries caused by gunshot increased over the 15-year study period. The majority were caused by civilian type low-velocity hand-guns and were purposefully and intentionally inflicted by others. Males in their third decade of life and of low socioeconomic status were most often the victims. The wounding effects of these low-velocity injuries were characteristic--small rounded entrance wounds, causing fragmentation of teeth and comminution of the underlying bone, usually without any exit wounds. A comminuted displaced type of fracture pattern was most frequently observed. Special investigations included plain film radiographs with more sophisticated investigations being requested where indicated. Definitive surgical management was initiated by early soft-tissue debridement. Both the mandibular and maxillary fractures had more open than closed reductions. Bone continuity defects as a result of the initial injury were usually reconstructed secondarily using free autogenous bone grafts. All the patients received anti-tetanus toxoid on admission and the majority received antibiotic treatment. The most common complications were sepsis, ocular and neurological complications and limitation of mouth opening. The postoperative sepsis rate was high (19%). The wounding effects of these low-velocity missile injuries are devastating and pose a treatment challenge to the maxillo-facial surgeon.  相似文献   
994.
In the search for explanation of persistent cognitive impairmentassociated with alcohol dependence, the possible role of liverdisease has aroused considerable interest. However, review ofthe relevant literature provides only ambiguous support forany general relationship between neuropsycho-logical statusand laboratory tests of liver function. We tested the generalhypothesis, and also two specific hypotheses relating particularliver function parameters (  相似文献   
995.
The pulsed tunable dye laser (PTDL) is generally considered to have a very low incidence of adverse effects, allowing it to become the treatment of choice for the majority of port wine stains (PWS). The low incidence of adverse effects has led to difficulties in determining the true incidence and type of adverse effect seen with this laser. We therefore undertook a retrospective study of 701 patients with PWS, who received 3877 full treatments to determine the incidence and type of adverse effects seen following treatment with the PTDL. Blistering and crusting were seen in 5·9% and 0·7% of patients, respectively, but were transient events which usually healed without permanent sequelae. Hyperpigmentation was the most frequently observed adverse effect seen in 9·1% of patients but generally showed gradual resolution over 6–12 months. Hypopigmentation was infrequent, seen in 1.4% of patients. The most significant adverse effects were atrophic and hypertrophic scarring seen in 4·3% and 0·7% of patients, respectively. Our observations show that there is a small but definite risk of atrophic scarring with a predisposition for younger patients. Hypertrophic scarring can occur albeit rarely and there may be a predisposition towards the neck. In most cases test areas were not predictive of scarring. This underlines the need for a full discussion of scarring risk in patients with PWS undergoing treatment with the PTDL.  相似文献   
996.
Specific cutaneous lesions are a rare occurrence in myelodysplastic syndromes (MDS). The concurrent association of blistering skin lesions similar to those in bullous pemphigoid (BP), even though a rare event, suggests that BP may be a paraneoplastic syndrome. We report an 86-year-old man who had a refractory anaemia with excess bone marrow blasts in transformation, who developed a generalized pruritic blistering eruption. Immunohistopathological tests showed subepidermal blisters with linear deposits of IgG and C3 along the basement membrane zone of the epidermis surrounding a tumoral dermal infiltrate of CD13+ and CD15+ cells. Immunoblotting studies using epidermal extracts revealed circulating IgG antibodies against three protein bands: a 210–215 kDa band. a 180kDa band which co-migrated with the BP 180 antigen, and a 190kDa band. The tumour infiltrate may have revealed antigenic determinants which led to the onset of BP. The concept of paraneoplastic pemphigoid remains to be either confirmed or invalidated by further epidemiological studies.  相似文献   
997.
Bone mineral density in patients with atopic dermatitis   总被引:1,自引:0,他引:1  
With the aim of evaluating the systemic effect of glucocorticoids (GCs), we measured bone mineral density (BMD) in 29 adult patients with chronic atopic dermatitis. BMD was measured in the lumbar spine and in the left femoral neck using dual–energy X–ray absorptiometry (DEXA). In the right calcaneus. BMD was measured using broad–spectrum ultrasound attenuation (BUA). For BMD, the patients with dermatitis did not differ from healthy controls. We did not find any statistically significant correlation between BMD and single risk factors, such as the barrier function of the skin (P = 0.08), the duration of the dermatitis (P = 0.58), and the use of oral GCs (P = 0.27) and potent topical GCs (P = 0.10). However, selected patients with severe disease, needing topical GCs of higher potency than hydrocortisone (HC), had lower values for lumbar BMD than the patients who had not used these preparations (–1.0 vs. +0.1 SD; P = 0.026). The lower lumbar BMD in this group could be explained by a long-term systemic effect of GCs.  相似文献   
998.
Ultraviolet radiation B (UVB) on the skin induces erythema, inflammation and modifications of the immune system. These changes have been reported after excessive short-term or long-term exposure to broad spectrum UVB. In this study, we examined the effects of local repetitive UVB irradiation of 311 nm wavelength on the skin of seven young volunteers. Skin biopsies were taken before and after UVB irradiation, and we immunohistochemically analyzed the expression of CD1a and HLA-DR antigens of Langerhans cells (LC), the possible infiltration of dermis/epidermis by CD11b macrophages, the modifications or the induction of intercellular adhesion molecule-1 (ICAM-1), E-selectin and vascular cell adhesion molecule-1 (VCAM-1) involved in the binding of leukocytes to the endothelial surface and the development of perivascular infiltrates of LFA-1+ mononuclear cells. We also determined the expression of substance P receptors (SPR) using biotinylated substance P (SPB). Exposure of UVB 311 nm induced a drastic reduction of CD1a+ cells and a moderate increase of HLA-DR+ dendritic cells in the epidermis without infiltration by CD11b macrophages. An increase of the binding of SPB to upper layer epidermal cells was noted in five of seven biopsies. In the dermis, vessel-associated ICAM-1 expression increased and an induction of E-selectin occurred on nearly 20 to 40% of endothelial cells, but VCAM-1 expression remained undetectable. The percentage of LFA-1+ cells did not change significantly after irradiation. These observations may be compatible with a selective role of UVB 311 nm on the skin immune response.  相似文献   
999.
Abstract Perioscan requires a plaque sample to detect the presence of enzymes capable of degrading N-benzoyl-DL-arginine-2-naphthylamide (BANA) from relatively few anaerobic periodontal pathogens. Periocheck assays the presence of neutral proteases in crevicular fluid. The aim of this study was to compare these test kits with traditional clinical methods of detecting periodontal disease and to monitor the ability of the kits to reflect the response to initial therapy. 19 patients with moderately severe chronic periodontitis were seen before and after a course of oral hygiene and root instrumentation consisting of 4 appointments. Clinical measurements and test assays were collected at 5 diseased sites and 2 healthy sites in each subject. Complete data from 125 sites were available for statistical analysis. At baseline Periocheck had a sensitivity of 88% and a specificity of 61% whereas Perioscan had a sensitivity of 99% and a specificity of 55%, when related to the clinical diagnosis. A composite clinical assessment, based on improvement or deterioration of one whole unit change of the subjective clinical indices and 2mm changes or greater in probing depth or probing attachment level, revealed 75 sites which improved following treatment, whereas 45 sites did not change and 5 sites deteriorated. The probability that the tests agreed with the clinical outcome after treatment, was calculated as 50.4% for Periocheck and 52% for Perioscan. The diagnostic kits did not reliably reflect the clinical assessment of periodontal disease in the cross sectional study, or the outcome following treatment.  相似文献   
1000.
The objective of this article is to describe various radiographic projections which can be used during endodontic therapy. Changes to the angulation of the X-ray beam in relation to the teeth and film can help diagnosis and treatment by producing images which provide additional information not always visible on radiographs taken with standard angulations. For example, changes in angulation can be useful to determine the number and curvature of roots and canals, to identify superimposed roots and to distinguish between anatomical landmarks and apical pathology. Although use of such techniques increases the diagnostic yield of films, it must be appreciated that such views lead to images that are less distinct because of inherent image distortion. Nevertheless, use of the various techniques during endodontics can provide substantial benefit for clinicians in their daily practice.  相似文献   
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