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91.
Aneurysmal bone cyst (ABC) is a benign lesion that often starts off the metaphysis of long bones and which, as it grows, may blow out bone. Only 3%-6% of cases are located in the skull. Spontaneous recovery has been reported. These cases occur more often in adults and in pelvic locations. Spontaneous regression at the skull level remains a very rare entity and few cases were described in the literature. Here, the authors report another case of spontaneous rapid regression of ABC of the skull in a 7-year-old boy revealed by gradually increasing painless hard swelling in the right frontal bone region with rapid spontaneous regression within 15 days. The authors will also proceed with an overview concerning this rare entity. 相似文献
92.
Collison IB 《Journal of analytical toxicology》2005,29(7):762-764
A 54-year-old woman (165 cm, 37 kg) was found dead in her home during a welfare check after not having been seen for at least three days. The body showed clear evidence of decomposition. Her head was in what appeared to be a pool of blood. The residence was clean, neat, and showed no evidence of violence. Insulin was found in the refrigerator, and syringes were in the kitchen cabinet. In agreement with these physical findings, her clinical history indicated that she suffered insulin-dependent diabetes mellitus. Autolytic changes were noticed at autopsy, and no obvious cause of death was demonstrated. The autopsy heart blood sample screened negative for cocaine and/or metabolite (benzoylecgonine), phenethylamines, opiates, and barbiturates by radioimmunoassay. The alcohol concentration was 0.51 g/dL in the blood, 0.04 g/dL in the brain, 0.08 g/dL in the liver, and 0.05 g/dL in the urine, and acetone levels were 42 mg/dL, 53 mg/dL, 14 mg/dL, and 19 mg/dL, respectively. Isopropanol was also present in all samples analyzed. The cause of death was ruled as metabolic acidosis due to diabetes mellitus. Possible bacterial postmortem production of ethanol is considered as an explanation for the increased concentration of ethanol found in the postmortem heart blood. 相似文献
93.
Johannes Poms Stephan Sacher Matthias Nixdorf Michael Dekner Sabine Wallner-Mang Ines Janssen 《Pharmaceutical development and technology》2019,24(6):739-750
An undesirable characteristic in lyophilized parenteral products is the potential presence of particulate matter in the final product, which may affect patient safety. In this study, quality risk management tools described in the International Conference on Harmonization Guideline Q9 were used to estimate the risks for a pharmaceutical manufacturing line, based on three critical quality attributes: (1) visible particulate matter; (2) lyo-cake collapse traces; and (3) lyo-cake melt-back traces. Together with a Process Failure Mode Effect Analysis (PFMEA), an input-output analysis of the individual unit operations identified seven major material classes of extrinsic particulate matter. In addition to the process assessment, an experimental investigation of the location of impurities in lyophilized products was performed. To that end, intentionally contaminated vials were examined to locate the particulate matter and its possible migration. The results emphasize the importance of a full transmission mode release testing since the particles may enter the interior of the lyo-cake. A theoretical explanation of the observed impurity locations is provided. 相似文献
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95.
Ines Dallel Intidhar Ben Salem Abderrahmen Merghni Wassim Bellalah Fadoua Neffati Samir Tobji Maha Mastouri Adel Ben Amor 《The Angle orthodontist》2020,90(4):532
ObjectivesTo evaluate the effect of orthodontic appliances on physicochemical, biochemical, and oxidative stress changes in salivary parameters during treatment.Materials and MethodsA cohort study was conducted with 112 healthy patients. Salivary samples were taken at baseline, 1 month, and 9 months after placement of the orthodontic appliances used in treatment.ResultsA statistically significant difference was observed in certain examined salivary parameters, including enzymes, electrolytes, and oxidative stress markers.ConclusionsThe use of aligners had a lower prevalence of disturbing salivary parameters. Orthodontist must consider these changes to prevent the occurrence of white spot lesions. 相似文献
96.
97.
Susanne Brakemeier Ines Eichler Hartmut Hopp Ralf K?hler Joachim Hoyer 《Cardiovascular research》2002,53(1):209-218
OBJECTIVE: Stretch-activated cation channels (SAC) have been suggested to act as endothelial mechanosensors for hemodynamic forces. Ca(2+) influx through SAC could induce an intracellular Ca(2+) signal stimulating Ca(2+)-dependent synthesis of vasodilators like NO, prostacyclin, or EDHF. In the present study we tested whether laminar shear stress (LSS) regulates SAC function. METHODS: Electrophysiological properties of SAC were investigated in human umbilical vein endothelial cells (HUVEC) subjected to defined levels of LSS in a flow-cone apparatus. RESULTS: In HUVEC, we identified a Ca(2+) permeable SAC that was activated by membrane stretch. Single-channel current densities of SAC in cell-attached patches were significantly increased in HUVEC exposed to an LSS of 5 dyn/cm(2) for 4 h (1.15+/-0.17 SAC/patch) compared to HUVEC kept in stationary culture (0.46+/-0.07 SAC/patch). Exposure of HUVEC to a higher LSS of 15 dyn/cm(2) for 4 h induced similar up-regulation of SAC (1.27+/-0.21 SAC/patch). After 24 h exposure to LSS of 15 dyn/cm(2), single-channel current densities of SAC remained up-regulated (1.07+/-0.18 SAC/patch) compared to controls. In addition, stretch-sensitivity of SAC (channel activity NP(o) at -30 mmHg) significantly increased after 2 h of exposure to LSS of 5 and 15 dyn/cm(2) and remained up-regulated after 24 h. Inhibition of protein kinases and tyrosine kinases by H7 and genistein, respectively, prevented LSS-induced alteration of SAC function. CONCLUSION: Single-channel current density and mechanosensitivity of SAC in HUVEC is up-regulated by LSS. Up-regulation of SAC function leads to enhanced mechanosensitive Ca(2+) influx, and represents a novel adaptive mechanism of the endothelium in the presence of altered hemodynamic forces. 相似文献
98.
Derouich-Guergour D Aldebert D Vigan I Jouvin-Marche E Marche PN Aubert D Ambroise-Thomas P Pelloux H 《Parasite immunology》2002,24(5):271-279
The in vitro regulation of tumour necrosis factor (TNF)-alpha receptors during Toxoplasma gondii infection of human MRC5 fibroblasts and human myelomonocytic THP-1 cells was investigated. Cells were infected with the virulent RH of T. gondii. TNFR membrane receptors were analysed by flow cytometry with biotinylated TNF-alpha. Shedding of the soluble form of TNFR1 and TNFR2 in cell culture supernatants was measured by enzyme-linked immunosorbent assay, and expression of mRNA production of TNFR1 and TNFR2 was analysed by quantitative real-time polymerase chain reaction, 1 h after infection. In the MRC5 cell line, T. gondii infection did not induce any up- or down-regulation of membrane TNFRs, soluble TNFRs or mRNA of TNFRs. However, THP-1 cell infection with living parasites induced a significant soluble TNFR1 release by THP-1 cells after 1 h. We detected an approximately 50% up-regulation (P < 0.01) of soluble TNFR1 in infected THP-1 cells compared to controls. No change in soluble TNFR2 levels was observed in the same conditions. Moreover, infection decreased the level of TNF membrane receptors, but had no effect on TNFR1 and TNFR2 mRNA levels. TNFR modulation by T. gondii infection, in vitro, depends on the cell type. Furthermore, our data suggest that living parasites control the shedding of the soluble form of TNFR1. This mechanism may influence the role of TNF-alpha in toxoplasmosis. 相似文献
99.
Matthias Augustin Christine Reich Ines Schaefer Ina Zschocke Stephan Jeff Rustenbach 《Journal der Deutschen Dermatologischen Gesellschaft》2008,6(2):113-120
Background: Benefit assessment of drugs and medical products has become a legally established feature of medical research. A standardized assessment of benefits using scientifically sound and valid methods is essential. Objective: Development, validation and practical evaluation of an instrument to record patient benefit in treatment of acne. Patients and Methods: In open interviews with n = 50 patients, possible benefits of the therapy from the patients' point of view were recorded. The item pool thus generated was reviewed by a panel of dermatologists, psychologists and patients and transferred to a 23‐item questionnaire. This is used prior to therapy to assess patients' desired benefits and after therapy to record the perceived benefits. The therapy goals and the resulting benefits are then used to generate a weighted ‘Patient Benefit Index’ (PBI). The procedure has been tested for its validity and feasibility in n = 923 patients with acne. Results: Patients accepted the instrument and deemed it to be easily understandable. Additionally, the method proved itself to be internally consistent, constructively valid and sensitive to changes. Conclusions: The Patient Benefit Index (PBI) is a valid and highly accepted practical instrument for recording patient benefit. The PBI permits an individualized, patient‐weighted assessment of the benefits of acne therapy. 相似文献
100.