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1.
This study evaluated, using Knoop hardness test, the polymerization depth of Rely-X dual-cured resin cement activated by chemical reaction alone (control group) or by chemical/physical mode with light curing through a 1.5-mm-thick ceramic layer (HeraCeram). Bovine incisors had their buccal surface flattened and hybridized. On this surface, a rubber mould (5 mm diameter; 1 mm high) was bulk filled with cement. Either a polyester strip or a 1.5-mm-thick disc of the veneering material was seated over this set. Light curing was performed with either conventional halogen light (QTH; XL2500) for 40 s, light-emitting diode (LED; Ultrablue Is) for 40 s or xenon plasma arc (PAC; Apollo 95E) for 3 s. In a control group, cement setting occurred by chemical reaction alone. After storage dry in dark (24 h/37 masculineC), the specimens (n=5) were sectioned for hardness (KHN) measurements at three depths in a microhardness tester (50 gf load/15 s). Data were submitted to ANOVA and Tukey's test (a = 0.05). Rely-X cement presented higher Knoop hardness values when the QTH and LED LCUs were used, compared to the control group and PAC. Light curing with PAC resulted in lower hardness compared to the control group. Cement hardness was significantly lower in deeper regions.  相似文献   
2.

Objective

An association of the programmed cell death-1 (PD-1) and its ligand PD-L1 with various types of malignant tumors has been established. This study aimed to investigate the role of the PD-L1/PD-1 pathway in oral squamous cell carcinoma (OSCC) and oral epithelial precursor lesions (OEPL).

Materials and methods

We examined 106 OSCC and 79 OEPL specimens for PD-L1 and PD-1 expression by immunohistochemistry. The results were compared with clinicopathological features of OSCC patients.

Results

In OSCC and OEPL specimens, PD-L1 expression was detected predominantly in epithelial or carcinoma cells, whereas PD-1 expression was found mainly in infiltrating or stromal lymphocytes. Seventy-two OSCC (67.9%) and 21 OEPL (26.6%) specimens were positive for PD-L1, and 73 OSCC (68.9%) and 23 OEPL (29.2%) specimens were positive for PD-1. PD-L1 and PD-1 expression levels were significantly different between OEPL and OSCC specimens (P < 0.001). There were significant positive correlations between PD-L1 and PD-1 expression in OEPL and OSCC specimens (P < 0.001). PD-L1 and PD-1 immunoreactivity was significantly associated with tumor size (P < 0.05). PD-L1 and PD-1 immunoreactivity in cases with advanced TNM staging was significantly higher than that in low staging cases (P < 0.01). There were significant correlations between PD-L1 and PD-1 expression in OSCC specimens and pathological variables such as stromal lymphocytic reaction (P < 0.05) and invasion depth (P < 0.01).

Conclusion

PD-L1 and PD-1 immunohistochemical status may be related to carcinogenesis, tumor progression, and prognosis in oral epithelial lesions. Agents targeting PD-1 and PD-L1 might be useful for OSCC treatment.  相似文献   
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A 71-year-old female presented to our hospital due to pain from the right hip joint to the lower abdomen. The pain had suddenly appeared and spontaneously disappeared more than 10 times during the past 2 years. She had visited many hospitals, but remained undiagnosed. The patient underwent a computed tomography (CT) scan of the pelvis, and a soft tissue shadow was seen between the external obturator and pectineal muscles. She was diagnosed with a right obturator hernia and underwent elective repair by laparoscopic trans-peritoneal hernioplasty (TAPP). 1 year has passed since the surgery, without any recurrence of the abdominal pain. Obturator hernias are rare, and most cases are found as incarcerated hernias. It is rare to find an obturator hernia without intestinal obstruction, or with the recurrent pain as in our case. We herein report a case in which an obturator hernia was undiagnosed and intermittent pain was experienced for 2 years prior to TAPP, which appears to have successfully treated the hernia.  相似文献   
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Liposome‐encapsulated hemoglobin with low O2‐affinity (l‐LEH) was shown to be protective in focal brain ischemia and reperfusion (I/R) in rats and primates. We tested l‐LEH in the transient whole brain ischemia in the Tokai high‐avoider rat (THA), which has been selected, mated, and bred over 77 generations for a high and consistent learning ability determined by the Sidman avoidance test (SAT). Young/naïve (before SAT) and adult/parent (after SAT) THA rats underwent acute and complete four‐vessel occlusion in the chest for 3 or 5 min, administration of 2 mL/kg of l‐LEH, saline, or homologous washed red blood cells (RBCs), reperfusion, and resuscitation. One week later, all rats underwent SAT, open‐field behavioral observation, Morris water maze tests, and morphological study. Whereas young/naïve rats treated with l‐LEH retained a rapid and consistent learning curve as in nonischemic controls, THA rats treated with RBCs or saline had retarded learning response on SAT as well as reduced cellularity in the amygdala. Adult/parent rats with established memory on SAT maintained perfect achievement even after I/R. In contrast, l‐LEH‐treated rats showed no better performance on Morris water maze (function) or cellularity of the CA1 sector of the hippocampus (morphology) compared with the rats treated with RBCs. Although task performance on SAT and Morris water maze appeared antithetical, morphological observations corresponded to the respective functions, suggesting that l‐LEH was protective only for the amygdala on SAT tasks but not for the CA1 sector of the hippocampus on spatial orientation as in our previous studies on focal brain I/R, where the cortex was preserved better than basal ganglia.  相似文献   
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Living‐donor lobar lung transplantation (LDLLT) is an established therapy for patients with end‐stage lung disease, but living‐donor lobar lung retransplantation (re‐LDLLT) is rarely reported. We previously reported a case of unilateral antibody‐mediated rejection after LDLLT in the presence of newly formed donor‐specific antibodies against a right‐lobe donor. The same patient developed contralateral bronchiolitis obliterans, resulting in bilateral bronchiolitis obliterans, but re‐LDLLT was successful. Pathological findings of the explanted lungs were consistent with the clinical course of the patient. One year after re‐LDLLT, the patient is doing well without any anti‐human leukocyte antigen antibodies. Four lobes from four different donors were transplanted in this patient. The first two lobes were rejected eventually, but the two lobes implanted later presented no signs of rejection at least for 1 year after the transplant. Herein, we report this rare case and compare the clinical course and pathological findings.  相似文献   
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