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901.
902.
Background: The treatment of deep dental decay has traditionally involved removal of all the soft demineralized dentine before a filling is placed. However, this has been challenged in three groups of studies which involve sealing soft caries into the tooth. The three main groups either remove no caries and seal the decay into the tooth, remove minimal (ultraconservative) caries at the entrance to a cavity and seal the remaining caries in, or remove caries in stages over two visits some months apart to allow the pulp time to lay down reparative dentine (the stepwise excavation technique). Objectives: To test the null hypothesis of no difference in the incidence of damage or disease of the nerve of the tooth (pulp), progression of decay and longevity of restorations irrespective of whether the removal of decay had been minimal (ultraconservative) or complete. Search strategy: The Cochrane Oral Health Group Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PubMed and EMBASE databases were searched. The reference lists in relevant papers were checked. Selection criteria: Randomized controlled trials and controlled clinical trials comparing minimal (ultraconservative) caries removal with complete caries removal in unrestored permanent and deciduous teeth. Data collection and analysis: Outcome measures recorded were exposure of the nerve of the tooth (pulp) during caries removal, patient experience of symptoms of pulpal inflammation or necrosis, progression of caries under the filling, time until the filling was lost or replaced. Due to the heterogeneity of the included studies the overall estimate of effect was calculated using a random‐effects model. Main results: Four studies met the inclusion criteria; two stepwise excavation studies and two ultraconservative caries removal studies. Partial caries removal in symptomless, primary or permanent teeth reduces the risk of pulp exposure. We found no detriment to the patient in terms of pulpal symptoms in this procedure and no reported premature loss or deterioration of the restoration. Authors’ conclusions: The results of this systematic review reject the null hypothesis of no difference in the incidence of damage or disease of the nerve of the tooth (pulp) irrespective of whether the removal of decay had been minimal (ultraconservative) or complete and accepts the null hypothesis of no difference in the progression of decay and longevity of restorations. However, the number of included studies is small and differ considerably. Partial caries removal is therefore preferable to complete caries removal in the deep lesion, in order to reduce the risk of carious exposure. However, there is insufficient evidence to know whether it is necessary to re‐enter and excavate further but studies that have not re‐entered do not report adverse consequences. 相似文献
903.
904.
Perianal fistulas: use of MR imaging for diagnosis 总被引:3,自引:0,他引:3
905.
Bladder cancer: staging with CT and MR imaging 总被引:10,自引:0,他引:10
Magnetic resonance (MR) imaging and computed tomography (CT) were compared in 30 patients with histologically proved bladder cancer. MR imaging was accurate in depicting the presence or absence of extravesical spread in 22 patients (accuracy, 73%; sensitivity, 82%; specificity, 62%), and CT was accurate in 24 patients (accuracy, 80%; sensitivity, 94%; specificity, 62%). The MR examinations of two patients were of undiagnostic quality and therefore considered to be technical failures. Each technique resulted in five false-positive and one false-negative examination for the diagnosis of extravesical tumor spread. In 28 patients the integrity of the bladder wall was assessed with MR imaging. In 22 patients the bladder wall was disrupted, and 18 of these patients had deep muscle invasion. In six patients the bladder wall was intact, and none of these patients had evidence of deep muscle invasion at pathologic examination. In this study MR imaging was slightly inferior to CT in the delineation of invasive tumors beyond the bladder wall. However, if one excludes from analysis the two patients with undiagnostic studies, there is no significant difference in accuracy between the two techniques. 相似文献
906.
Changes in cell spreading and cytoskeletal organization are induced by adhesion to a fibronectin-fibrin matrix 总被引:5,自引:1,他引:4
Plasma fibronectin (pFN) cross-linked to fibrin during the injury response provides a provisional matrix required for cells to begin tissue repair. Using a synthetic matrix of pFN and fibrin as a substrate for cell adhesion and spreading, we have determined that pFN covalently cross-linked to fibrin into a complex multimer is functionally distinct from pFN immobilized onto a plastic surface. NIH- 3T3 cells on a FN-fibrin matrix reach 50% of the maximal cell area of cells spread on FN-coated plastic. They neither attach nor spread on cross-linked fibrin alone. Cells on pFN-fibrin matrices form few prominent stress fibers and exhibit clear differences in membrane ruffling and filopodial extension when stained with rhodamine-labeled phalloidin. Interestingly, these differences are enhanced by upregulation of protein kinase C. These data suggest that cell-FN interactions can be modified by the molecular context of the protein within the extracellular matrix resulting in distinct cell morphology and cytoskeletal organization. 相似文献
907.
908.
H Galjaard M Mekes D E Josselin de Jong JE M F Niermeijer 《Clinica chimica acta; international journal of clinical chemistry》1973,49(3):361-375
A method is described enabling prenatal diagnosis of glycogenosis II (Pompe's disease) within 7–10 days after amniocentesis in the 14th–16th week of pregnancy. The procedure is based on amniotic fluid cell cultivation on thin plastic foil, freezing and freeze-drying of the cells and subsequent microdissection of pieces of plastic foil each containing 70–250 lyophilized cells. These are incubated in microliter volumes of substrate. The extinction or fluorescence values are measured in microcuvettes adapted to a normal spectrofluorometer or in microcapillaries using a microscope spectrofluorometer design. The methods developed are compared with conventional biochemical analyses. 相似文献
909.
Pulse Cyclophosphamide for Severe Neuropsychiatric Lupus 总被引:1,自引:1,他引:0
BOUMPAS DT; YAMADA H; PATRONAS NJ; SCOTT D; KLIPPEL JH; BALOW JE 《QJM : monthly journal of the Association of Physicians》1991,81(3):975-984
We Studied the effect of parenteral pulse cyclophosphamide therapyin nine patients with active systemic lupus erythematosus andsevere central nervous system involvement. Seven patients hadfocal neurological deficits and/or seizures associated withabnormalities on cerebrospinal fluid analysis and/or magneticresonance imaging. Two patients had organic brain syndrome withpsychosis and normal cerebrospinal fluid and/or magnetic resonanceimaging analysis. Six patients were unresponsive to treatmentwith high dose corticosteroid. Cyclophosphamide 0.75–1.0g/m2 body surface area, was administered intravenously everymonth for at least 2 months. Eight patients had a complete recoveryor recovered with minor residuals. Cyclophosphamide was welltolerated with few side effects. We conclude that parenteralpulse cyclophosphamide is an effective adjunctive therapy forthe management of patients with active systemic lupus erythematosusand central nervous system symptoms. 相似文献
910.