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991.
This study investigated the effect of the AMPA receptor antagonist 6,7-dinitroquinoxaline-2,3-dione (DNQX) microinjected into the core and shell sub-regions of the accumbens nucleus (Acb), on the level of fear/anxiety and emotional learning, in female rats submitted to the elevated plus-maze (EPM), an animal model of anxiety. Bilateral microinjections of DNQX (330 and 660 ng) into the Acb shell (AP, +1.08 to +2.16) induced an anxiolytic-like effect in relation to rats microinjected with vehicle, since there was an increased percentage of entries in the open arms of the maze. The 660 ng DNQX microinjection into the Acb shell also increased the percentage of entries into the open arms in relation to 660 ng DNQX microinjection into the Acb core. Prior DNQX microinjections in both core and shell sub-regions of the Acb failed to impair the emotional learning, since the animals exhibited an increase of the open arm avoidance on EPM Trial 2 in relation to EPM trial 1. DNQX microinjections into both sub-regions of the Acb did not change the number of entries into the enclosed arms, either in the EPM Trial 1 or in the EPM Trial 2, which indicates an absence of drug-induced locomotor impairment. Similarly, DNQX microinjections into both sub-regions of the Acb failed to alter the total arm entries, rearing, grooming and head-dipping frequency. The anxiolytic-like effect induced by DNQX suggests that the AMPA receptor in the Acb shell, but not in the Acb core, may underlie anxiety regulation in the EPM.  相似文献   
992.
Using the polymerase chain reaction we have isolated and sequenced cDNA clones corresponding to the polymorphic first domain of the DRβ1 chain from the DR4, “Dw13” cell line, JHa. We have found that the JHa DRβ1 allele differs from previously reported Dw13 alleles by a single amino acid substitution at position 86. The functional relevance of this polymorphism is supported by the reactivity pattern of a T-cell clone, E38. E38 is an alloreactive T-cell clone which reacts with all Dw14 stimulator cells and all Dw13-positive cells tested except the “Dw13”- positive homozygous typing cell line JHa. Inhibition studies with monoclonal antibodies revealed the stimulating determinant to be on DR and not on DQ or DP molecules. These data indicate that position 86 of the DRβ1 chain can play an important role in the formation of determinants recognized by T cells.  相似文献   
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Objectives

To investigate whether chronic temporomandibular disorder (TMD) patients showed any changes in swallowing compared to a control group. Moreover, it was examined whether swallowing variables and a valid clinic measure of orofacial myofunctional status were associated.

Material and methods

Twenty-three patients with chronic TMD, diagnosed with disc displacement with reduction (DDR) and pain, according to the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD), and 27 healthy volunteers (control group) were compared. Surface electromyography (EMG) of the temporalis, masseter, sternocleidomastoid, and suprahyoid muscles was performed during swallowing tasks of thin liquid (10 and 15 mL) and spontaneous saliva. Data were normalized.

Results

Compared to the control group, TMD patients showed a prolonged duration of swallowing for liquid and saliva and required a longer time to reach the activity peak and half the integral. While the overall mean value of the relative peaks was similar for the groups, the suprahyoid peak was significantly lower in the TMD group during swallowing of liquid. Moreover, TMD patients recruited the jaw elevator muscles proportionally more than controls. The orofacial myofunctional status was moderately correlated with EMG parameters.

Conclusion

Patients with chronic TMD showed temporal prolongation and changes in the relative activity of the muscles during the swallowing tasks.

Clinical relevance

The present results contribute additional evidence regarding the reorganization of muscle activity in patients with chronic TMD.

  相似文献   
997.
Crithidia oncopelti, C. deanei, andC. desouzai are flagellates of the Trypanosomatidae family that present bacterium-like endosymbionts in their cytoplasm. Direct and indirect lectin-gold labeling techniques were used at the electron microscopic level in Lowicryl K4M-embedded cells to demonstrate the presence of intracellular lectin-binding sites. We used the lectinsUlex europaeus I, Griffonia simplicifolia II, Ricinus communis I, Arachis hypogaea, G. simplicifolia I, Wistaria floribunda, Limulus polyphemus, andCanavalia ensiformis, which recognize -l-fucose, - and -N-acetylglucosamine, -galactose and -N-acetylgalactosamine, -galactose, -galactose, -N-acetylgalactosamine, sialic acid and -d-mannose, and -d-glucose residues, respectively. The nucleus was the cellular structure most frequently labeled by the lectins. The Golgi complex was seldom labeled, whereas the endoplasmic reticulum and the flagellar pocket presented a large number of binding sites. Symbionts had their two unit membranes weakly labeled by the different lectins but displayed no labeling of the space between the membranes.  相似文献   
998.
Clonal rearrangements of immunoglobulin heavy chain genes as well as both T cell receptor (TCR) delta and gamma genes were found in four cases of blast crisis of Ph+ chronic myeloid leukaemia with unequivocal B cell precursor (common) immunophenotype. In one case, the TCR beta chain gene was also rearranged. Although the developmental sequence of TCR delta, gamma and beta rearrangements in T lymphocytes appeared to be respected, a full phenotypic effect, characteristic of T cell was not observed in these otherwise typical 'common' blast cells. Cytogenetic analysis ruled out the occurrence of TCR rearrangement due to structural chromosome changes. A high incidence of unexpected TCR gene rearrangements has been previously reported in the de novo 'common' acute lymphoblastic leukaemias (ALL). Our cases of chronic myeloid leukaemia (CML) in lymphoid blast crisis show that genotypic similarities may exist between these two haematological entities.  相似文献   
999.

Purpose  

The aim of the study was to assess the role of CA 15.3, CT and positron emission tomography (PET)/CT in patients with breast cancer and suspected disease relapse after primary treatment.  相似文献   
1000.
We observed a 34-year-old man who was incidentally found to have an adrenal mass during surgical follow-up for perforated ulcer. The patient was subjected to I-123 MIBG scintigraphy, 68Ga-DOTANOC PET/CT, and F-18 DOPA PET/CT. Only F-18 DOPA PET/CT showed evidence of an avid adrenal mass. A CT-guided biopsy was performed and it was suggestive for pheochromocytoma. He underwent surgery and a pheochromocytoma, about 40 mm in diameter, was detected. Traditionally, I-123 MIBG scintigraphy has been used in detecting chromaffin cell tumors, but more recently it had been demonstrated that a certain part of pheochromocytoma could be false-negative on scintigraphy.  相似文献   
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