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71.
Psychogenic nonepileptic seizures (PNES) are paroxysmal clinical events that are often misdiagnosed as epileptic seizures, but which are not associated with electrographic discharge. Brain connectivity changes occurring during PNES are not known. We studied functional connectivity (Fc) in two patients with drug-resistant epilepsy, explored by stereotactic electroencephalography (EEG), in whom we recorded both epileptic seizures (ES) and PNES. Functional connectivity using pair-wise nonlinear correlation was computed between signals from seven brain areas: amygdala, hippocampus, lateral temporal cortex, anterior insula, orbitofrontal cortex, prefrontal cortex, and lateral parietal cortex. We assessed changes in global Fc during PNES in comparison with a background period. During PNES, a global decrease of Fc occurred between the different brain regions studied, compared with the interictal period. In both patients, decreased Fc was prominent in connections involving the anterior insula and parietal cortex. In conclusion, some PNES are associated with ictal functional disconnection between brain areas, particularly involving the parietal cortices and the anterior insula.  相似文献   
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Two female patients, 42 and 30 years old, respectively, died of acute nonlymphocytic leukemia 43 and 38 months, respectively, after a subsequent treatment: chemotherapy for one and irradiation and chemotherapy for the other, following excision of a malignant glioma. At the time of death, both seemed to be in complete remission of their brain tumor. Both had been treated with procarbazine and nitrosoureas. The latter were responsible for severe myelosuppressive episodes and seem to have played an essential role in the induction of the leukemia. In one case, a myelodysplasia was observed before the onset of the AL and the diagnosis of refractory anemia with excess of blasts seemed warranted. Secondary acute leukemias are rare in the evolution of malignant gliomas and the usefulness of subsequent radiochemotherapy cannot be questioned at the present time. The risks involved in this therapy are minor when compared to the short-term fatal prognosis of this type of tumor. Cancer 52:222-226, 1983.  相似文献   
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Deletion of the late cornified envelope (LCE) genes LCE3B and LCE3C has recently been identified as a risk factor for psoriasis. Expression of 16 LCE genes of LCE groups 1, 2, 3, 5, and 6 was examined in vivo and in vitro. Quantitative PCR demonstrated that moderate to high LCE expression was largely confined to skin and a few oropharyngeal tissues. Genes of the LCE3 group demonstrated increased expression in lesional psoriatic epidermis and were induced after superficial injury of normal skin, whereas expression of members of other LCE groups was down-regulated under these conditions. Immunohistochemistry and immunoelectron microscopy demonstrated that LCE2 protein expression was restricted to the uppermost granular layer and the stratum corneum. Stimulation of in vitro reconstructed skin by several psoriasis-associated cytokines resulted in induction of LCE3 members. The data suggest that LCE proteins of groups 1, 2, 5, and 6 are involved in normal skin barrier function, whereas LCE3 genes encode proteins involved in barrier repair after injury or inflammation. These findings may provide clues to the mechanistic role of LCE3B/C deletion in psoriasis.  相似文献   
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Crustacean primary cell culture: A technical approach   总被引:10,自引:0,他引:10  
Crustacean cell culture has gained attention as a potent model to assist in the development of diagnostic reagents and probes for use in the shrimp, crayfish and lobster industries. The availability of such cellular tools is especially important to industries which use intensive aquaculture methods and thus have increased risk of disease problems. Indeed, crustacean cell cultures offer potential for studying the effects of pathogens in vitro and for increasing our knowledge on developmental and sexual maturation processes, or endocrine regulation in crustaceans. Although numerous attempts have been undertaken, no established cell line of marine crustaceans has been reported to date. However, primary cultures obtained from various organ sources are reported with increasing frequency. They represent the first steps towards the establishment of cell lines and they provide useful information concerning the most suitable cell culture conditions involved in the survival and proliferative capacity of the various tissues.  相似文献   
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Biventricular pacing (BiV) is emerging for patients with dilated cardiomyopathy (DCM) and asynchrony. We measured basal asynchrony and early resynchronization by radionuclide angioscintigraphy (RNA) in order to predict long-term evolution of ventricular function after BiV. Thirty-four patients (NYHA Class III-IV,65.4 +/- 11 years) with large QRS(179 +/- 18 ms)were implanted with BiV and studied by RNA before (D0), at day 8 (D8), and during follow-up(20 +/- 7 months). We calculated left and right ejection fractions, the interventricular dyssynchrony (TRVLV), and the apicobasal dyssynchrony (Tab). LVEF improved from 20.2 +/- 8.1%(D0) to27.1%+/- 12.6%(follow-up,P < 0.003 vs D0) and RVEF from 28.6%+/- 13%(D0) to 34.3 +/- 11.5%(follow-up,P < 0.03 vs D0). Inter- (DeltaTRVLV) and intraventricular resynchronization was immediate and remained stable: TRVLV decreased from 68.3 +/- 38 ms(D0) to 13.4 +/- 48.5 ms(D8) and1.8 +/- 39.2 ms(follow-up,P < 0.0001 vs D0); and Tab from 45.8 +/- 64.1 msto-18 +/- 68(D8) and-28.3 +/- 53.6 ms(follow-up,P < 0.0001 vs D0). Early inter- and intraventricular resynchronization (DeltaTab) at D8 were related to late LVEF and RVEF improvement. Together, an LVEF > 15% and a significant interventricular dyssynchrony (TRVLV > 60 ms) at D0 have a sensitivity of 79% and a positive predictive value of 83% to predict an improvement of LVEF superior to 5% at follow-up. In DCM patients, BiV resynchronizes ventricles early and in the long-term, while RVEF and LVEF improve progressively. Patients with large electromechanical dyssynchrony benefit most from BiV.  相似文献   
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We wanted to test the following hypothesis: the location of the tibial and femoral ACL attachments measured by a navigation system differs from their actual anatomic location. A total of 10 gross specimens were studied. The standard navigated procedure was used. Metallic reference pins were implanted around the tibial and femoral ACL attachments and palpated with a navigated stylus. Their position was recorded in comparison with the same tibial or femoral reference point. All measurements were repeated with a caliper. Caliper and navigated measurements were compared with appropriate statistical tests at a 0.05 level of significance. There was a significant difference between caliper and navigated measurements at the tibia in absolute value (maximal range of 4 mm, mean difference about 2 mm), but the difference ratio was low (about 3%); there was no significant difference between caliper and navigated measurements at the femur. There was a strong correlation and a good agreement between caliper and navigated measurements. It is likely that these differences have few, if any, clinical relevance. We demonstrated that the navigation system used during the present study has the potential to enhance the precision of the intra-operative measurement of the tunnel placement during ACL replacement.  相似文献   
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