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81.
A 60-year-old female underwent screening colonoscopy. Narrow-band imaging (NBI) without magnification showed a 20-mm, well-demarcated brownish area located close to the dentate line of the anal canal. Conventional white-light imaging revealed an ill-defined, flat lesion with scattered reddish spots at the same site. Magnifying endoscopy with NBI (M-NBI) revealed abnormal microvessels with dilatation, tortuosity, caliber change and various shapes that were similar to the intrapapillary capillary loop patterns seen in esophageal squamous cell carcinoma in situ. Endoscopic submucosal dissection (ESD) was performed, and on histological examination, the resected specimen showed squamous cell carcinoma (SCC) in situ and clear surgical margins. Thus, NBI is an efficient method for detecting superficial SCC in the anal canal and M-NBI may be useful for determining the extent of the lesion. During screening colonoscopy, the anal region should be carefully observed using NBI, as early detection offers a greater opportunity for ESD which is a less invasive procedure.  相似文献   
82.
Primary squamous cell carcinoma is rarely observed, with a reported incidence of 0.04–0.07 % of all gastric cancers. An 81-year-old male underwent chemoradiotherapy for type 1 gastric cancer of the posterior wall of the cardiac region in 2005. The tumor disappeared after 1 year of therapy, following which an area of white epithelium, approximately 30 mm in diameter and continuous with the esophageal mucosa, became visible. Biopsy of the white epithelium indicated normal squamous epithelium. An elevated lesion was subsequently detected in the area of white epithelium on upper gastrointestinal endoscopy during a follow-up examination 5 years after therapy. As a biopsy of the same site indicated squamous cell carcinoma, we performed endoscopic submucosal dissection. Histopathological examination indicated high-grade fibrosis due to radiotherapy and showed a moderately differentiated squamous cell carcinoma invading the scarred portion. We describe a case where the developmental process of a squamous cell carcinoma was observed using endoscopy, including narrow band imaging with magnification. This carcinoma likely originated from squamous metaplasia that developed after chemoradiotherapy was administered for a gastric cancer.  相似文献   
83.
84.
The present study evaluated the effect of various surface treatments for zirconia ceramics on shear bond strength between an indirect composite material and zirconia ceramics. In addition, we investigated the durability of shear bond strength by using artificial aging (20,000 thermocycles). A total of 176 Katana zirconia disks were randomly divided into eight groups according to surface treatment, as follows: group CON (as-milled); group GRD (wet-ground with 600-grit silicon carbide abrasive paper); groups 0.05, 0.1, 0.2, 0.4, and 0.6 MPa (airborne-particle abrasion at 0.05, 0.1, 0.2, 0.4, and 0.6 MPa, respectively); and group HF (9.5% hydrofluoric acid etching). Shear bond strength was measured at 0 thermocycles in half the specimens after 24-h immersion. The remaining specimens were subjected to 20,000 thermocycles before shear bond strength testing. Among the eight groups, the 0.1, 0.2, 0.4, and 0.6 MPa airborne-particle abraded groups had significantly higher bond strengths before and after thermocycling. The Mann-Whitney U-test revealed no significant difference in shear bond strength between 0 and 20,000 thermocycles, except in the 0.2 MPa group (P = 0.013). From the results of this study, use of airborne-particle abrasion at a pressure of 0.1 MPa or higher increases initial and durable bond strength between an indirect composite material and zirconia ceramics.  相似文献   
85.

Objectives

This study aims to evaluate the effect of both feldspathic porcelain coating of zirconia frameworks and priming agents on shear bond strength between an indirect composite material and zirconia frameworks.

Materials and methods

A total of 462 airborne-particle-abraded zirconia disks were divided into three groups: untreated disks (ZR–AB), airborne-particle-abraded zirconia disks coated with feldspathic porcelain, (ZR–PO–AB), and hydrofluoric acid-etched zirconia disks coated with feldspathic porcelain (ZR–PO–HF). Indirect composite (Estenia C&;B) was bonded to zirconia specimens with no (CON) or one of four priming agents—Clearfil Photo Bond (CPB), Clearfil Photo Bond with Clearfil Porcelain Bond Activator (CPB?+?activator), Estenia Opaque primer, or Porcelain Liner M Liquid B (PLB)—with or without an opaque material (Estenia C&;B Opaque). All specimens were tested for shear bond strength before and after 20,000 thermocycles. The Steel–Dwass test and Mann–Whitney U test were used to compare shear bond strength.

Results

In ZR–AB specimens, the initial bond strength of the CPB and CPB?+?Activator groups was significantly higher as compared with the other three groups (P?P?Conclusion Feldspathic porcelain coating of a Katana zirconia framework enhanced the bond strength of Estenia C&;B indirect composite to zirconia independent of surface treatment. The use of a silane coupling agent and opaque material yields durable bond strength between the indirect composite and feldspathic-porcelain-coated zirconia.

Clinical relevance

The results of the present study suggest that feldspathic porcelain coating of zirconia frameworks is an effective method to obtain clinically acceptable bond strengths of a layering indirect composite material to a zirconia framework.  相似文献   
86.
A 20-year-old man presented with pain and recurrent hemarthrosis in the right knee. Magnetic resonance imaging of the knee showed a lesion with homogeneous low signal intensity on T1-weighted images and a heterogeneous, low to high signal intensity on T2-weighted images. At arthroscopy, the mass was located between the posterior cruciate ligament and the posterior knee joint capsule. The tumor was excised through a posterior approach and histologically diagnosed as a nodular fasciitis. Intra-articular nodular fasciitis is a very rare clinicopathologic entity. The current case showed the unique clinical feature of recurrent hemarthrosis at initial presentation, which has not been previously reported.  相似文献   
87.
The Otton frog (Babina subaspera) and Holst’s frog (Babina holsti) are both endangered sister species belonging to family Ranidae. For extensive genetic and ecological research of these species, we isolated and characterized 8 new microsatellite loci of the Otton frog and validated cross-amplification in Holst’s frog along with 8 previously reported loci. The total number of alleles and the expected heterozygosity of newly isolated loci in the Otton frog population ranged from 5 to 12 and from 0.620 to 0.905, respectively. We also confirmed cross-amplification in 4 of the new loci and in all previously reported loci in Holst’s frog with the same level of polymorphism as the Otton frog. Our findings suggest that these novel loci will be applicable for conservation genetic studies across varying scales.  相似文献   
88.
Wiskott–Aldrich syndrome (WAS) is a condition with variable expression, which causes persistent thrombocytopenia and, in its complete form, also causes small platelets and humoral immunodeficiency. A 14-year-old boy, diagnosed with WAS but never treated, presented with symptoms of heart and renal failure. His right buccal region was swollen and his right first molar showed a cyst-like image on dental X-ray films. The boy's symptoms were attributed to an infected cyst, greatly aggravated by WAS-related immunodeficiency. The boy was sedated and the affected tooth and cyst were enucleated. Invasive treatment was safely achieved by paying close attention to whole-body management.  相似文献   
89.

Background

Superficial temporal artery-to-middle cerebral artery (STA-MCA) anastomosis is a common procedure for neurosurgeons. The surgery necessarily requires accurate and speedy manipulation of microscope, for which a specific training is needed. Unexpected bypass occlusion sometimes happen during surgery.

Objective

Generally, conventional interrupted or continuous suture has been used for vascular anastomosis, despite various ideas have been attempted in the other surgery fields. We propose a horizontal mattress suture technique for intracranial microvascular bypass surgery. This is the first report ever published on intracranial vascular anastomosis.

Methods

We had four patients of STA-MCA bypass surgery with “mattress anastomosis” from March to May of 2012.

Results

During the procedure, there was no bypass occlusion and good patency was confirmed in all cases.

Conclusion

Intimae of the recipient and the donor blood vessel contact each other precisely with this technique. Although a long-term assessment of patency is needed, it is useful for the intracranial bypass surgery.  相似文献   
90.
The MERA monopivot centrifugal pump has been developed for use in open‐heart surgery, circulatory support, and bridge‐to‐decision for up to 4 weeks. The pump has a closed‐type, 50‐mm diameter impeller with four straight paths. The impeller is supported by a monopivot bearing and is driven by a radial‐flux magnet‐coupling motor. Because flow visualization experiments have clarified sufficient pivot wash and stagnation at the sharp corner of the pivot support was suggested, sharp corners were removed in the design stage. The index of hemolysis of the pump operating at more than 200 mm Hg was found to be lower than that of a commercial pump. Four‐week animal tests were then conducted two times; improvement of thrombus formation was seen in the female pivot through modification of female pivot geometry. Overall antithrombogenicity was also recorded. Finally, to assure mid‐term use, an additional 4‐week durability test revealed that the rate of the axial pivot wear was as small as 1.1 µm/day. The present in vitro and in vivo studies revealed that the MERA monopivot centrifugal pump has sufficient hemocompatibility and durability for up to 4 weeks.  相似文献   
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