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971.
972.
973.
Results are reported from a study on the in vitro separation and identification of leachables from three different polymer-based dental filling materials by using a combined method of gas chromatography and mass spectrometry. The median number of separable organic leachables in these materials was between 14 and 22. Of these organic leachables the following were identified and quantified: DL-camphorquinone, 4-dimethylaminobenzoic acid ethyl ester (DMABEE), drometrizole, 1,7,7-trimethylbicyclo[2,2,1]heptane, 2,2-dimethoxy[1,2] diphenyletanone (DMBZ), ethyleneglycol dimethacrylate (EGDMA), and triethyleneglycol dimethacrylate (TEGDMA). Three of the leachables have previously been shown to provoke allergy. The range of log P(ow) values (representing the lipophilicity of these compounds) varied between 1.09 and 4.20. By multivariate data analysis, selected leachables from the tested materials were shown to separate into characteristic patterns. The results contribute to a characterization of potential hazardous compounds in polymer-based dental filling materials.  相似文献   
974.
T cell non-Hodgkin lymphoma is characterized by uncontrolled cellular proliferation of immature malignant clones. HIV-associated T cell non-Hodgkin lymphoma comprises a heterogeneous group of lymphoproliferative neoplastic entities classified according to morphological, immunological, genetic and clinical features. Extranodal T cell non-Hodgkin lymphoma of the oral cavity is uncommon. A case is presented with extranodal T cell non-Hodgkin lymphoma as an initial sign of HIV-infection. The characteristics of HIV-associated non-Hodgkin lymphoma are discussed.  相似文献   
975.
The authors present a series of 175 femoropopliteal (below-knee) and 65 femorotibial reconstructions with the human umbilical vein (HUV) graft performed over an eight year period. With a mean follow-up of 36.7 months (range one month to 84 months) the early patency rate of 89% decreased to 54% after five years. Longterm patency was found to be primarily related to the location of the distal anastomosis and the quality of the outflow, showing a statistically significant decrease after repeat revascularization. Early thrombosis, even in the absence of a technical failure and late aneurysmal degeneration remain the major problems associated with the use of the HUV graft. It is therefore recommended that these reconstructions be preserved for patients with advanced ischemia or a limited life-expectancy.  相似文献   
976.
Background: Hemorrhage is commonly treated with intravenous infusion of crystalloids. However, the dynamics of fluid shifts between body fluid spaces are not completely known, causing contradictory recommendations regarding timing and volume of fluid infusions. The authors have developed a turnover model that characterizes these fluid shifts.

Methods: Conscious, chronically instrumented sheep (n = 12) were randomly assigned to three protocol groups: infusion of 25 ml/kg of 0.9% saline over 20 min (infusion only), hemorrhage of 300 ml (7.8 +/- 1.1 ml/kg) over 5 min (hemorrhage only), and hemorrhage of 300 ml over 5 min followed by infusion as noted above (hemorrhage plus infusion). A two-compartment volume turnover kinetic model containing seven model parameters was fitted to data obtained by repeated sampling of hemoglobin concentration and urinary excretion.

Results: The volume turnover model successfully predicted fluid shifts. Mean baseline volumes of the central and tissue compartments were 1799 +/- 1276 ml and 7653 +/- 5478 ml, respectively. Immediate fluid infusion failed to prevent hemorrhage-induced depression of cardiac output and diuresis. The model suggested that volume recruitment to the central compartment after hemorrhage was primarily achieved by mechanisms other than volume equilibration between the two model compartments.  相似文献   

977.

Objectives  

Socio-economic differences in the frequency of smoking, alcohol consumption, drug use, physical exercise, and attitudes toward smoking were explored in an sample of Slovak adolescents (1 370 boys, 1 246 girls, mean age 15 years).  相似文献   
978.
OBJECTIVE: The objective of this study was to evaluate the long-term effects of anti-TNF-alpha treatment on temporomandibular joints (TMJs), oral mucosa, and salivary flow in RA. STUDY DESIGN: Seventeen patients received infusions of TNF-alpha blocking agents after 0, 2, and 6 weeks, and then every 8 weeks until week 54 (follow-up). Clinical dysfunction index (Di) for the TMJ system, salivary flow, disease activity score (DAS28), and other medical assessments were calculated at weeks 0 and 54. RESULTS: Median Di was 5.0 (range 0-21) at baseline and 1.0 (range 0-6) (P = .001) at follow-up. Mean salivary flow was 3.2 mL/15 minutes at baseline and 4.6 at follow-up (P = .055). Two (11.7%) of the patients developed oral candidiasis during the period of treatment. The median DAS28 was 6.2 (range, 4.7-7.7) at baseline and 4.1 (range, 1.6-6.8) at follow-up (P = .001). CONCLUSION: We conclude that anti-TNF-alpha blocking treatments have beneficial effects on oral as well as general manifestations of RA.  相似文献   
979.
Abstract:  5-aminolevulinic acid heptyl ester was investigated in human adenocarcinoma WiDr cells and in healthy skin of athymic nude mice in comparison with 5-aminolevulinic acid (ALA). Incubation of WiDr cells with ALA and ALA heptyl ester resulted in production of protoporphyrin IX (PpIX). Concentrations higher than 0.01 m m of ALA heptyl ester and higher than 1 m m of ALA were cytotoxic. The dark cytotoxicity was not related to PpIX. Intracellular localization, photocytoxicity and photobleaching rate of PpIX were the same for both drugs, although a 100 times lower concentration of ALA heptyl ester (0.01 m m ) was needed in comparison with ALA (1 m m ) to induce the same level of PpIX. ALA heptyl ester, topically (but not systemically) applied, is a promising candidate for fluorescence diagnosis and photodynamic therapy. Special attention must be focused on the concentrations of ALA heptyl ester; as excess may lead to cytotoxicity and inefficient PpIX generation.  相似文献   
980.

Background/Purpose  

The present study attempted to replicate our previous finding that depressive symptoms are a risk factor for mortality in stable chronic obstructive pulmonary disease (COPD), but in a different population with a different measure of depressive symptoms. We further investigated whether type D personality is associated with mortality in patients with COPD and whether it explains any relationship observed between depressive symptoms and mortality.  相似文献   
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