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101.
European Archives of Psychiatry and Clinical Neuroscience - Chronic benzodiazepine use is common in patients with mental illness and is associated with cognitive impairment. It is unclear whether...  相似文献   
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The mononuclear complex, [Co(TAMEN)](ClO(4))(2) (DMSO), containing the Mannich base N,N'-tetra-(4-antipyrylmethyl)-1,2-diaminoethane (TAMEN) as ligand, was synthesized and characterised by conductometric, electronic and infrared spectroscopic properties. The single-crystal X-ray structure show the presence of two well defined units, [Co(TAMEN)](2+) and (ClO(4))(-). The complex cation contains cobalt(II) in the pseudo octahedral environment created by the N(2)O(4) donor set of TAMEN. The cobalt(II) complex have been screened for its cytotoxic activity against three cultured human cell lines established from hepatoma (Hep G2), breast (MCF-7) and lung (A549) cancers as well as on non-tumor bovine kidney (MDBK) cells. The cytotoxic activity of the ligand TAMEN was assessed on one tumor (Hep G2) and one non-tumor (MDBK) cell lines. The cobalt(II) compound was found to decrease in a time- and concentration- dependent manner the viability of tumor (A549, MCF-7, Hep G2) cell lines, while the ligand TAMEN expressed proliferative activity on hepatoma (HepG2) and bovine kidney (MDBK) cells, especially after prolonged incubation.  相似文献   
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Poly(ether ether ketone) (PEEK) and its composites are recognized as alternative bearing materials for use in arthroplasty because of their mechanical properties. The objective of this project was to evaluate the biological response of two different kinds of carbon fiber-reinforced (CFR) PEEK compared with ultra-high molecular weight polyethylene (UHMWPE) in vivo as a standard bearing material. Wear particles of the particulate biomaterials were injected into the left knee joint of female BALB/c mice. Assessment of the synovial microcirculation using intravital fluorescence microscopy as well as histological evaluation of the synovial layer were performed 7 days after particle injection. Enhanced leukocyte–endothelial cell interactions and an increase in functional capillary density as well as histological investigations revealed that all tested biomaterials caused significantly (P < 0.05) increased inflammatory reactions compared with control animals (injected with sterile phosphate-buffered saline), without any difference between the tested biomaterials (P > 0.05). These data suggest that wear debris of CFR-PEEK is comparable with UHMWPE in its biological activity. Therefore, CFR-PEEK represents an alternative bearing material because of its superior mechanical and chemical behavior without any increased biological activity of the wear particles, compared with a standard bearing material.  相似文献   
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PURPOSE: To evaluate the influence of cyclic loading and type of adhesive on the shear bond strength of the bracket-cement-enamel bond. METHODS: The materials studied were: Transbond XT (a Bis-GMA resin composite cement), Fuji Ortho LC (a resin-modified glass-ionomer cement), and Fuji IX Fast (a conventional glass-ionomer cement). The shear bond strength (SBS) and the shear bond fatigue limits (SBFL) were determined after 72-hour storage in 37 degrees C water for the cement itself, the button-cement interface, the cement-enamel interface, and the bracket-cement-enamel system. The SBFL was determined with the aid of the "staircase method" at 10,000 cycles. The results were analyzed using ANOVA and Tukey HSD post hoc test (P < 0.05). RESULTS: ANOVA showed significant differences between the SBS of the materials. Fatigue was observed in all substrate combinations, with the exception for the Fuji IX Fast cement-enamel and the Fuji Ortho LC bracket-cement-enamel combinations.  相似文献   
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BACKGROUND:

The glycoprotein YKL‐40 is synthesized both by cancer cells and by tumor‐associated macrophages and plays a functional role in tumor progression. Consequently, high serum YKL‐40 levels have been associated with a poor prognosis in patients with several cancer types. However, the role of YKL‐40 has not been established in nonsmall cell lung cancer (NSCLC).

METHODS:

Pretreatment serum levels of YKL‐40 were determined in 189 patients with NSCLC (143 men and 46 women; median age, 62 years;, age range, 41‐76 years). Twelve percent of patients had stage IIIB disease, and 88% had stage IV disease. Ninety‐eight patients received combined gemcitabine and vinorelbine, and 91 received combined gemcitabine, vinorelbine, and cisplatin as first‐line chemotherapy. The median overall survival was 37 weeks.

RESULTS:

Patients had a median serum YKL‐40 level of 209 ng/mL (range, 19‐2153 ng/mL). No correlation was observed between overall survival and the type of chemotherapy regimen used, tumor stage, sex, or histologic types. Patients with high serum YKL‐40 levels (greater than the median level for all patients [209 ng/mL]) had a significantly shorter survival than patients with serum YKL‐40 levels below the median (median survival, 32 weeks vs 41 weeks; P = .007). In multivariate analysis, the serum YKL‐40 level, the presence of bone lesions, and the serum lactate dehydrogenase level were independent, statistically significant prognostic factors.

CONCLUSIONS:

The pretreatment serum YKL‐40 level was identified as a new, independent prognostic biomarker in patients with metastatic NSCLC and may help to determine the individual prognosis of these patients. Cancer 2010. © 2010 American Cancer Society.  相似文献   
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