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91.
92.
Background:  Addictive drugs activate extracellular signal regulated kinase (ERK) in brain regions critically involved in their affective and motivational properties. The aim of this study was to demonstrate the ethanol-induced activation of ERK in the nucleus accumbens (Acb) and in the extended amygdala [bed nucleus of the stria terminalis lateralis (BSTL) and central nucleus of the amygdala (CeA)] and to highlight the role of dopamine (DA) D1 receptors in these effects.
Methods:  Ethanol (0.5, 1, and 2 g/kg) was administered by gavage and ERK phosphorylation was determined in the nucleus Acb (shell and core), BSTL, and CeA by immunohistochemistry. The DA D1 receptor antagonist, SCH 39166 (SCH) (50 μg/kg), was administered 10 minutes before ethanol (1 g/kg).
Results:  Quantitative microscopic examination showed that ethanol, dose-dependently increased phospho-ERK immunoreactivity (optical and neuronal densities) in the shell and core of nucleus Acb, BSTL, and CeA. Pretreatment with SCH fully prevented the increases elicited by ethanol (1 g/kg) in all brain regions studied.
Conclusions:  The results of this study indicate that ethanol, similar to other addictive drugs, activates ERK in nucleus Acb and extended amygdala via a DA D1 receptor-mediated mechanism. Overall, these results suggest that the D1 receptors/ERK pathway may play a critical role in the motivational properties of ethanol.  相似文献   
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PURPOSE: The aim of this study was to compare the value of endoluminal ultrasonography (ELUS) with magnetic resonance imaging (MRI) for preoperative staging of rectal carcinoma. METHODS: Thirty-seven consecutive patients were examined by ELUS and MRI. Imaging results were compared with pathohistologic studies. A tumor extending beyond the bowel wall was considered to be positive and one within the bowel wall was considered negative. Lymph node involvement was considered present if nodes equal to or greater than 5 mm in diameter were found in the perirectal tissue. For evaluating the differences between the two methods, the Mc Nemar test was performed. RESULTS: T-Staging was correct in 88.2 percent (30/34) of patients by ELUS and in 82.3 percent (28/34) by MRI (difference not significant). N-Staging was correct in 80 percent (20/25) by ELUS and in 60 percent (15/25) by MRI (difference of borderline significance). A comprehensive preoperative staging (T + N) was made correctly in 68 percent (17/25) by ELUS and in 48 percent only (12/25) by MRI (difference not significant). CONCLUSIONS: We suggest that ELUS and MRI must be evaluated within the framework of established parameters when treatment modalities such as preoperative radiation therapy and local or radical surgical approach must be decided.  相似文献   
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Clinical Rheumatology - Kawasaki disease (KD) is the most frequent cause of acquired heart disease in children in high-income countries because of coronary artery involvement. Risk factors for...  相似文献   
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The absence or very low levels of plasminogen cause a rare disabling disease called ligneous conjunctivitis, characterized by the growth of fibrin-rich pseudomembranes in the conjunctiva and on other mucosal surfaces. Several mutations have been detected in the plasminogen gene of patients affected with ligneous conjunctivitis. The human plasminogen gene, located on chromosome 6, has a marked homology with the genes belonging to the plasminogen-apo(a) family, and with a number of pseudogenes and plasminogen-like genes located on chromosome 2. This work describes a series of nucleotide variations related to genes other than the plasminogen one, found during the genetic characterization of plasminogen defect in two unrelated patients with ligneous conjunctivitis. The results of automated sequences of each exon and intron-exon boundaries were compared with those of the human plasminogen gene from the NCBI gene bank. In particular, a co-amplified gene on chromosome 2 mimicking a 14 bp deletion in exon 5 of the plasminogen gene was identified by sequencing two different bands obtained from a long run of the PCR exon 5 product in NuSieve agarose gel, and by PstI restriction enzyme analysis of the same amplicons. Moreover, 21 single nucleotide exchanges due to plasminogen-like genes co-amplification were observed, namely one in exon 1, two in exon 4, three in exons 3, 5 and 16, four in exon 13, and five in exon 17. In conclusion, these data confirm the difficulty of plasminogen genetic analysis and may help researchers to better identify the true plasminogen gene mutations causing molecular defects.  相似文献   
99.
Purpose

To evaluate the reproducibility of the 2D shear wave elastography (2D-SWE) method and to identify the prognostic factors of breast lesions.

Methods

In this prospective study, 44 female patients were consecutively included from January 2020 to September 2021. All patients showing visible masses at B-mode ultrasound underwent to clinical evaluation, followed by qualitative and quantitative 2D-SWE by two different operators with over 15-year and 2-year experience, respectively. Subsequently, patients underwent to surgical treatment after core needle biopsy. Reproducibility of qualitative and quantitative 2D-SWE was evaluated by Cohen’s kappa and intraclass correlation coefficient (ICC). Clinical, imaging, and histopathological data and 2D-SWE evaluations were analysed with Spearman's rank correlation test.

Results

The mean age of the patients was 55 years?±?12. The mean histological and ultrasound tumour size of were 23.1 mm?±?13.2 and 17.2 mm?±?10.2, respectively. The interobserver agreement showed a good reproducibility limited to the qualitative evaluation colour maps (Cohen’s kappa?=?0.603) and to the quantitative evaluation E ratio (ICC?=?0.771). Correlation analysis between the ultrasound and 2D-SWE values and the clinical-pathological parameters showed a significant relationship between E ratio and Elston–Ellis grading (P?<?0.030) and between tumour size and Elston–Ellis grading (P?<?0.041).

Conclusion

The 2D-SWE has shown good reproducibility among operators with different experience. It could be a promising tool in the evaluation of some prognostic factors in ultrasound visible breast cancer.

  相似文献   
100.
We have previously shown that the life cycles of several viruses are influenced by host-cell redox states. Reports of the antioxidant activities of the plant polyphenol resveratrol (RV) prompted us to investigate its effects on influenza virus replication in vitro and in vivo. We found that RV strongly inhibited the replication of influenza virus in MDCK cells but that this activity was not directly related to glutathione-mediated antioxidant activity. Rather, it involved the blockade of the nuclear-cytoplasmic translocation of viral ribonucleoproteins and reduced expression of late viral proteins seemingly related to the inhibition of protein kinase C activity and its dependent pathways. RV also significantly improved survival and decreased pulmonary viral titers in influenza virus-infected mice. No toxic effects were observed in vitro or in vivo. That RV acts by inhibiting a cellular, rather than a viral, function suggests that it could be a particularly valuable anti-influenza drug.  相似文献   
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