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991.
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993.
A rare cause of breast mass that mimics carcinoma: Foreign body reaction to amorphous surgical material 总被引:2,自引:0,他引:2
Yazici B Sever AR Mills P Fish D Jones S Jones P 《Wiener klinische Wochenschrift》2007,119(15-16):497-499
A breast mass caused by foreign body type granulomatous reaction to surgical material is a very rare lesion and may mimic carcinoma. Reported foreign materials have included suture materials, silicone, paraffin, gunpowder and carbon particles used for localization of a nonpalpable breast lesions. To our knowledge, a foreign body reaction to gauze sponge has not been reported previously. A 58-year-old woman who had an enlarging mass that mimicked breast carcinoma, due to foreign body reaction to gauze sponge is presented here, and relevant literature is reviewed. 相似文献
994.
Claro S Kanashiro CA Oshiro ME Ferreira AT Khalil RA 《The Journal of pharmacology and experimental therapeutics》2007,322(3):964-972
The use of gamma-radiation in treatment of pelvic cancer is associated with injury of healthy surrounding tissues and disorders of intestinal motility; however, the cellular mechanisms involved are unclear. We tested the hypothesis that exposure of visceral smooth muscle cells (SMCs) to gamma-radiation induces apoptosis via activation of specific protein kinase C (PKC) isoforms. Cultured SMCs and slices from guinea pig ileum smooth muscle longitudinal layer (GPISMLL) were exposed to 10 to 50 Gy. Flow cytometry in gamma-radiated SMCs showed increased percentage of cells in the sub-G(0)/G(1) phase, a hallmark of apoptosis. gamma-Radiation-induced reduction in cell survival was partially but significantly alleviated with the PKC inhibitors. Sections of gamma-irradiated GPISMLL showed DNA fragmentation and apoptotic bodies analyzed by the terminal deoxynucleotidyl transferase dUTP nick-end labeling method, whereas the plasma and nuclear membranes were preserved. Confocal microscopy in gamma-radiated SMCs labeled with annexin V-fluorescein showed an increase in apoptotic cells and phosphatidylserine externalization. Contraction of GPISMLL strips in response to KCl and acetylcholine was reduced in tissues exposed to 30 and 50 Gy. gamma-Radiation of GPISMLL caused an increase in PKC activity in the particulate fraction, a decrease in the cytosolic fraction, and increased particulate/cytosolic PKC activity ratio. Western blot analysis revealed significant amounts of alpha- and epsilon-PKC in the cytosolic fraction of control GPISMLL. gamma-Radiation caused an increase in the amount of alpha- and epsilon-PKC in the particulate fraction and a decrease in the cytosolic fraction. Data suggest that gamma-radiation induces apoptosis, growth arrest, and contractile dysfunction in visceral SMCs of GPISMLL via activation and translocation of alpha- and epsilon-PKC isoforms. 相似文献
995.
Gastrocutaneous fistula after gastrostomy tube removal may persist for a prolonged period. We present a case of a 58-year-old woman with a GCF that had persisted for 5 months following the removal of an endoscopically-placed gastrostomy tube (PEG). Conservative therapy with anti-acid medications and administering motility agents was unsuccessful. For the closure of the GCF, the endoscopic metal clips were used to close the fistula. 相似文献
996.
997.
AIM: The aim of this article is to report a case of bilateral multiple impacted supernumerary teeth. A discussion of possible mechanisms of development is also presented along with a concise review of the literature. BACKGROUND: Supernumerary teeth occur in the context of various scenarios in the primary and the permanent dentition. Multiple supernumerary teeth are a rare finding especially in the absence of associated syndrome or disease. REPORT: A case of bilateral multiple impacted supernumerary teeth localized to the mandibular premolar region is reported. Some of the supernumerary teeth as well as the erupted premolars had persistent open apices. Coronal malformation of the right maxillary first premolar was another interesting finding. There was an absence of any concomitant disease. SUMMARY: The aforementioned combination of findings has not been reported previously. The anatomical, geometrical, and spatial relationships of supernumerary teeth with their erupted equivalents may shed light on some controversial aspects of the etiology. 相似文献
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999.
PURPOSE: To evaluate the influence of thermal and mechanical load cycling on the microtensile dentin bond strength of two self-etching and one total-etch adhesives. METHODS: The adhesive materials were: a two-step self-etch adhesive (Clearfil SE Bond), a one-step self-etch adhesive (Hybrid Bond), and a total-etch one-step adhesive (Admira Bond). Sixty freshly extracted human third molars were used. In each tooth, a Class I cavity (4 x 4 mm) was prepared in the occlusal surface with the pulpal floor extending about 1 mm into dentin. The teeth were divided into three groups (n=20). Each group was restored with the resin composite Clearfil APX using one of the adhesives. After restoration, 10 teeth in each group were thermocycled between 5 degrees C and 55 degrees C, (dwell time 3 minutes, 5,000 cycles). The same teeth were then mounted in a fatigue loading machine to receive an intermittent load of 125 N at 52 cycles/minute for 4,000 cycles. Subsequently, each tooth was sectioned longitudinally, bucco-lingually and mesio-distally to get rectangular slabs 1-1.2 mm in thickness for the microtensile test. Each slab was then placed in a universal testing machine and tensile load was applied at a cross-head speed of 0.05 mm/minute. RESULTS: Without loading procedures, there was no significant difference in the bond strength of the tested adhesives. In contrast to Admira Bond and Clearfil SE Bond, fatigue loading resulted in a significant reduction of the bond strength for Hybrid Bond when compared to the unloaded restorations. 相似文献
1000.
In LeFort I surgery, the separation of the pterygomaxillary junction is done by osteotomy. Although the osteotome is positioned too close to the maxillary artery and its branches during pterygomaxillary separation, postoperative complications from vascular injuries are uncommon. We describe an unusual occurrence of a maxillary artery pseudoaneurysm after LeFort I and bilateral sagittal split osteotomies for maxillary advancement and mandibular setback as well as (anterior sliding) genioplasty. In a patient with class III occlusion and midface retrusion, the significant bleeding began 10 days postoperatively, which was controlled by anterior and posterior nasal packing. The bleeding recurred 28 days after surgery; thus, vascular anatomy in the pterygomaxillary area is reviewed, pseudoaneurysm was diagnosed on selective carotid angiography and successfully treated by embolization; and 2-year follow up was uneventful. 相似文献