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71.
This study investigated the effects of NaOCl on resin-tooth bonds to simulate the situations of long-term durability and caries invasion. Resin-tooth bonded specimens were produced with the use of two resin adhesives (Excite and One-Bond). Resin-tooth bonded beams (adhesive area; 0.9 mm2) were serially sectioned and the specimens were immersed in 10% NaOCl medium for 0 (control), 2, 4, and 6 h after being stored in water for 24 h. After immersion, microtensile bond tests were performed. SEM fractography was conducted to calculate each failure mode by image analysis. In addition, the adhesive interface was examined with the use of TEM. In the control specimens, enamel bond strengths had no difference between Excite (45.6 +/- 15.0) and One-Bond (56.9 +/- 12.9). On the other hand, dentin bond strengths had significant difference between Excite (80.6 +/- 21.2) and One-Bond (50.7 +/- 11.2). The bond strengths decreased with increased storage time for both systems with enamel and dentin bonds. The deteriorated mineralized dentin of beams resulted in bond-strength reduction for resin-enamel bonds. For dentin bonding, the adhesive interface was gradually dissolved from the outer to the center portion of the beam. The depletion of collagen fibrils within the demineralized dentin or hybrid layer deformation was found under SEM and TEM examinations. These morphological changes are responsible for bond strength reduction of resin-dentin bonds.  相似文献   
72.
A case of undifferentiated carcinoma arising from benign lymphoepithelial lesion (BLEL) of the parotid gland was studied by light and electron microscopy. Histopathologically, the carcinoma was composed of pleomorphic anaplastic cells showing an undifferentiated type among abundant lymphoid tissue forming germinal center. Among the prominent lymphoid tissue, epithelial hyperplasia, dysplasia, and squamous metaplasia of the duct epithelium were found. Dysplastic epithelium revealed a transition with carcinomatous component in some areas. On the electron microscopic observation, the tumor cells were poorly differentiated, possessing desmosomes and intracytoplasmic filaments. The patient is alive and well 2 months after resection of the tumor, but has a high titer of serum Epstein-Barr virus capsid antigen in IgG. Eighty five cases of the malignant lymphoepithelial lesion (MLEL) including the present case are summarized.  相似文献   
73.
An autopsy case of a 58-year-old woman with massive cardiac Involvement of adult T cell leukemia/lymphoma (ATLL) is reported. She developed cardiac failure due to aortic and mitral regurgitation with cardiac infiltration of ATLL cells, and underwent replacement of both aortic and mitral valves. Studies of the cut-surfaces revealed diffuse thickening of the subendocardial wall of the left chamber with widespread whitish-brown tumor infiltrates. In the regions surrounding the replaced aortic and mitral valves there was also massive tumor cell infiltration. The tumor cells infiltrating the cardiac muscle wall were T cell in origin and exhibited Leu-3a (CD4)-positive immunoreaction. Ultrastructurally, tumor cells contained markedly indented nuclei and some were attached directly to the muscle cells. These findings suggest that this was an unusual form of ATLL with widespread involvement of the heart.  相似文献   
74.
Purpose

Intravesical bacillus Calmette–Guérin (BCG) is the standard of care for bladder carcinoma in situ (CIS). The response to BCG therapy against CIS is generally assessed by random bladder biopsy (RBB). In this study, we examined the necessity of routine RBB after BCG therapy.

Methods

We retrospectively identified 102 patients who were initially diagnosed with CIS with or without papillary tumor and received subsequent 6–8-week BCG therapy. Thereafter, all patients underwent voiding cytology analysis, cystoscopy, and RBB to evaluate the effects of BCG therapy. We evaluated the association between clinical parameters (voiding cytology and cystoscopy findings) and the final pathological results by RBB specimens.

Results

According to the pathological results of RBB, 30 (29%) patients had BCG-unresponsive disease (remaining urothelial carcinoma was confirmed pathologically) and 20 were diagnosed with CIS. Positive/suspicious voiding cytology and positive cystoscopy findings were well observed in patients who had BCG-unresponsive disease compared with their counterparts (p?=?0.116, and p?<?0.001, respectively). The sensitivity (Sen.), specificity (Spe.), positive predictive value (PPV), and negative predictive value (NPV) of voiding cytology were 50%, 68%, 39%, and 77%, respectively. The values for cystoscopy findings were as follows: Sen.: 87%, Spe.: 57%, PPV: 46%, and NPV: 91%. The values for their combination (having either of them) were as follows: Sen.: 100%, Spe.: 44%, PPV: 43%, and NPV: 100%.

Conclusion

RBB after BCG therapy for patients with negative voiding cytology and negative cystoscopy may be omitted because their risk of BCG-unresponsive disease is significantly low (NPV: 100%).

  相似文献   
75.
Neurosurgical Review - Although transvenous embolization (TVE) via the superior ophthalmic vein (SOV) is adopted in treating cavernous sinus dural arteriovenous fistula (CS DAVF), its effect on the...  相似文献   
76.
BackgroundThe Shoulder Pain and Disability Index (SPADI) is a simple disease specific questionnaire that is used to evaluate the impact of shoulder disorders. The purpose of this study was to translate the SPADI into Japanese (SPADI-Jp) and evaluate its reliability and validity in Japanese patients with shoulder disorders.MethodsCross-cultural adaptation of the SPADI was performed according to international guidelines. A total of 100 patients with shoulder disorders participated in this study. Each participant was asked to finish the SPADI-Jp, Disability of Arm, Shoulder and Hand (DASH), and the Short-Form 36 (SF-36) at the initial visit. Thirty-four patients repeated the SPADI-Jp to assess the test–retest reliability. The test–retest reliability was quantified using the interclass correlation coefficient (ICC), while Cronbach's alpha was calculated to assess the internal consistency. The construct validity was assessed using Spearman's rank correlation coefficients.ResultsInternal consistency in the SPADI-Jp was very high (0.969), as measured by the Cronbach's alpha. The ICC of the SPADI-Jp was 0.930. There was a strong, positive correlation between the DASH and the SPADI-Jp (r = 0.837, p < 0.001). The SPADI-Jp was significantly correlated with most of the SF-36 subscales. The correlations of the SPADI-Jp with physical subscales of the SF-36 were stronger than those with the other subscales.ConclusionsWe demonstrated that the SPADI-Jp is a reliable and valid self-assessment tool. Because cross-cultural adaptation, validation, and reliability of the disease-specific questionnaire for shoulder pain and disability have not been evaluated in Japan, the SPADI-Jp can be useful for evaluating such patients in the Japanese population.  相似文献   
77.
78.
We describe a case history of a 24-year-old male with osteogenesis imperfecta (OI) who developed osteosarcoma of the left thigh. High-dose ifosfamide therapy caused marked tumor regression of multiple lung metastases. Immunohistochemically, the tumor cells were diffusely positive for the p53 protein. Mutation of the p53 gene was not detected by direct genomic sequencing of exons 4–8. The radiographic characteristics, including irregularly distributed osteolytic lesions and cortical discontinuity, should not be confused with hyperplastic callus formation, a benign process. A biopsy is critical to establish the differential diagnosis between osteosarcoma and common hyperplastic callus formation in OI; however, it must be applied with great care.  相似文献   
79.
The neurotoxicity ofn-hexane is thought to be caused ultimately by 2,5-hexanedione (2,5-HD), one of then-hexane metabolites. The potentiation ofn-hexane neurotoxicity by co-exposure with MEK, therefore, is suspected to be related to kinetics of 2,5-HD in blood. To clarify the kinetics ofn-hexane metabolites in the mixed exposure ofn-hexane and MEK, rats were exposed to 2000 ppmn-hexane or a mixture of 2000 ppmn-hexane and 2000 ppm MEK, and the time courses of serumn-hexane metabolites were determined. 2,5-HD in serum increased until 2 h after the end of exposure, when serum 2,5-HD concentration reached a peak of 16.35 g/ml in then-hexane-alone group. In contrast, 2,5-HD in the mixed exposure group increased much more slowly during and after exposure than in then-hexane-alone group. It reached a peak of 2.12 g/ml at 8 h after the end of exposure. Serum MBK, a precursor of 2,5-HD in the co-exposure group, was about half in then-hexane-alone group during exposure. However, MBK decreased more slowly in the co-exposure group than in then-hexane-alone group after the end of the exposure. The results suggest that co-exposed MEK might inhibit oxidation ofn-hexane and decrease clearance ofn-hexane metabolites. Co-exposed MEK did not increase serum 2,5-HD, which was considered a main neurotoxic metabolite. Therefore the enhancement of neurotoxicity could not be attributed to increased serum 2,5-HD in the co-exposed group. The mechanism of enhancement of neurotoxicity ofn-hexane by MEK should be studied further.  相似文献   
80.
Glioblastoma cells secrete transforming growth factor- (TGF-), whichhas a variety of immunosuppressive properties. We investigatedthe effect of irradiation TGF- secretion by malignantglioma cells. Three malignant glioma cell lines (T98G,A172, KG-1-C) were cultured and irradiated using 10and 50 Gy Linac radiation. After further culturefor 36 hours in serum-free culture medium, thesupernatants were collected. The TGF- activity in theculture supernatants was determined using a specific bioassay.The levels of the active form and totalTGF- in the supernatants from irradiated malignant gliomacells decreased compared to those from un-irradiated cells.However, since irradiation inhibited the growth of tumorcells, the amount of TGF- secretion per cellin irradiated cells tended to increase after irradiation.These results suggest that malignant glioma cells canstill secrete TGF- and activate latent TGF- evenafter large dose irradiation, despite the inhibition oftumor growth.  相似文献   
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