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991.
992.
Central giant cell granuloma (CGCG) is a benign lesion of unknown etiology that especially affects the jaws, usually appears in patients younger than 30 years and is more common in females than in males. Lesions generally occur in the anterior portion of the jaws and mandibular lesions frequently cross the midline. The conventional treatment of CGCG is surgical removal. According to clinical and radiological features, the extent of tissue removal ranges from simple curettage to an en bloc resection. We present an 8-year-old male patient, lack of any systemic disease or syndrome, complaining from painless swelling of the left posterior part of the mandible. In intraoral examination, a firm, expansive swelling with overlying intact mucosa, extending from mandibular primary canine to the distal portion of the left permanent first molar, was detected. A panoramic radiograph exhibited an ill-defined radiolucent lesion of 1.5 x 2 cm, extending from left permanent first molar to angulus mandibula and a well-defined, unilocular radiolucent lesion of 1 x 2 cm, extending from angulus to ramus mandibula on the asymptomatic right side. After the assessment of MRI, surgical removal was planned with the otorhinolaryngology department and lesions were totally removed under general anesthesia in two consecutive operation. Histopathologic examination revealed typical giant cell granuloma containing numerous multinucleated giant cells embedded in a fibrous stroma. In presenting this case we aimed to share occurrence of bilateral central giant cell granulomas of the mandible in the absence of hyperparathyroidism and associated syndromes, which is very rare in the literature. 相似文献
993.
Jangwook P. Jung Arun K. Nagaraj Emily K. Fox Jai S. Rudra Jason M. Devgun Joel H. Collier 《Biomaterials》2009,30(12):2400-2410
Self-assembling peptides and peptide derivatives bearing cell-binding ligands are increasingly being investigated as defined cell culture matrices and as scaffolds for regenerative medicine. In order to systematically refine such scaffolds to elicit specific desired cell behaviors, ligand display should ideally be achieved without inadvertently altering other physicochemical properties such as viscoelasticity. Moreover, for in vivo applications, self-assembled biomaterials must exhibit low immunogenicity. In the present study, multi-peptide co-assembling hydrogels based on the β-sheet fibrillizing peptide Q11 (QQKFQFQFEQQ) were designed such that they presented RGDS or IKVAV ligands on their fibril surfaces. In co-assemblies of the ligand-bearing peptides with Q11, ligand incorporation levels capable of influencing the attachment, spreading, morphology, and growth of human umbilical vein endothelial cells (HUVECs) did not significantly alter the materials' fibrillization, β-turn secondary structure, or stiffness. RGDS-Q11 specifically increased HUVEC attachment, spreading, and growth when co-assembled into Q11 gels, whereas IKVAV-Q11 exerted a more subtle influence on attachment and morphology. Additionally, Q11 and RGDS-Q11 were minimally immunogenic in mice, making Q11-based biomaterials attractive candidates for further investigation as defined, modular extracellular matrices for applications in vitro and in vivo. 相似文献
994.
E Alibrahim RN Gibson J Vincent T Speer N Collier C Jardine 《Journal of Medical Imaging and Radiation Oncology》2006,50(2):136-142
This study aimed to assess the ability of CT–i.v. cholangiography to show the perihilar biliary and cystic duct anatomy and to assess the relative performance of axial, maximum intensity projection and surface rendered displays. We also assessed the correlation between serum bilirubin levels and adequacy of biliary opacification. Spiral CT was carried out following infusion of 100 mL of Biliscopin in 181 patients with suspected biliary disease. The display of biliary anatomy was of high quality, with 91% of patients having good opacification of at least first‐order bile ducts and 84% having good opacification of at least third‐order right and left hepatic ducts. The quality of biliary opacification correlated inversely to serum bilirubin levels, with levels above two to three times the normal value being associated with lower rates of good opacification. Maximum intensity projection and surface rendered reformats aided anatomical interpretation to a similar degree. The relative frequency of types of perihilar branching patterns and cystic duct junctional anatomy correlated closely to those reported from previous anatomical studies. 相似文献
995.
Zusammenfassung Zur Feststellung des Heilwertes von Malariaheilmitteln eignet sich die natürliche Halteridieninfektion des afrikanischen Reisfinken. Nach der Behandlung mit einem wirksamen Präparat verschwinden die Parasiten aus der Blutbahn, um später mehr oder weniger stark wieder aufzutreten, während die Infektion bei den unbehandelten Kontrollen zeimlich gleichmäßig weiter fortbesteht.Die Arbeit wurde mit Unterstützung der Notgemeinschaft der Deutschen Wissenschaft durchgeführt. 相似文献
996.
A case of hypertrophic osteoarthropathy associated with achalasia is reported. The signs and symptoms of hypertrophic osteoarthropathy abated after treatment of the patient's achalasia with Heller's myotomy. A review of the literature regarding the cause of hypertrophic osteoarthropathy is discussed briefly. 相似文献
997.
A digital imaging system that employs a novel scanning x-ray tube, a multiple-slit assembly (MSA), and an image intensifier (II)-TV digital system is described. Use of the MSA can increase x-ray utilization by a factor of 100 over that obtained with single-slit systems. Scatter and veiling glare can be reduced substantially by synthesizing the final image from a number of multiple-slit images, resulting in improvement in contrast sensitivity. An experimental prototype system consisted of a conventional x-ray tube and an II-TV digital system used in conjunction with mechanical scanning of the MSA. Attenuation curves measured with an aluminum stepwedge showed that scatter and veiling glare were eliminated by this approach. Reconstructed images of phantoms were superior to images obtained with conventional wide-beam exposure. Physical parameters related to design of the scanning x-ray tube and a digital system for acquiring images of the chest are discussed. 相似文献
998.
Experiments were conducted to study proteoglycan biosynthesis by rabbit articular chondrocytes cultured in the presence of NSAIDs and 35SO4(2-) for up to 8 days. Both articular cartilage explants and confluent chondrocyte monolayer culture models were used. Medium was changed every 2 days and the [35SO4]proteoglycans which had accumulated in the medium and the extracellular matrix during the culture intervals were assayed separately. In long-term experiments, drugs were removed on day 8, and proteoglycan production during a 10-12 day culture interval also was assayed. The drugs studied were diclofenac, indomethacin, ketoprofen, piroxicam and tiaprofenic acid, at concentrations of 0, 0.1, 1, 10, 50 and 100 micrograms/mL. Whereas proteoglycan production by cell cultures was maximal early in the culture period, explants produced more proteoglycans as time progressed. The highest concentrations of all of the drugs, especially diclofenac and indomethacin, inhibited proteoglycan secretion by both cell and explant cultures. However, after removal of the drugs from the cultures, suppressed proteoglycan production reversed to levels equivalent to, or higher than controls in the cell cultures, but largely persisted in explant cultures. About 70-80% of proteoglycans produced by explants were retained in the matrix, whereas about 80-90% of proteoglycans produced by cell cultures were secreted into the medium. Where drugs inhibited proteoglycan production, the levels were reduced by approximately the same proportions in both extracellular matrix and culture medium fractions. Of the NSAIDs examined only ketoprofen demonstrated a stimulatory effect on PG synthesis in explant cultures at a physiological concentration (0.1 microgram/mL). 相似文献
999.
Rapid assessment of a patient with possible major peripheral vascular injury is essential to preserve limb function. Intravenous digital subtraction angiography (IV DSA) allows rapid evaluation of these patients without the need for intraarterial examination. We report our experience in 295 vessels studied by IV DSA for the evaluation of possible traumatic arterial injury to the extremities or neck. Of our study population requiring angiography (469 patients), 63.4% were appropriate candidates for IV DSA. Of the vessels studied by IV DSA, 93.6% required no further radiologic evaluation. A normal appearance on IV DSA study indicates no major vascular injury; patients with positive studies may proceed to surgery without further interventional assessment. 相似文献
1000.
Using the in situ perfused rat liver model, the effect of erythromycin (Ery) on the disposition of cyclosporin A (CyA) and the major human metabolite, AMl, was investigated. Prior to perfusion experiments, oral dosing was carried out for three days on three groups of male Sprague—Dawley rats (300–350 g), involving pretreatment with water (control and H2O/Ery groups) or erythromycin (Ery oral group). On the fourth day, perfusion experiments took place using standard techniques, with the addition of 20 mg Ery to the H2O/Ery and Ery oral groups, and 2.5 mg CyA to all groups. Perfusate and bile samples were collected and assayed for CyA and AMl by HPLC. Results indicated that inhibition of CyA metabolism had occurred as the CyA concentration in perfusate was significantly higher in both Ery groups at all times compared to the control group, and the levels of AMl in both perfusate and bile were significantly lower than in the control group. There was also a marked reduction in the apparent metabolic clearance of CyA in the Ery groups. It was concluded that AMl production had been inhibited by Ery, the most likely mechanism being inhibition of the isoenzyme CYP3A with which Ery forms a stable complex. 相似文献