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41.
42.
Potocki–Lupski syndrome is a condition mainly characterized by infantile hypotonia, developmental delay/intellectual disability (DD/ID), and congenital anomalies, caused by duplications of the 17p11.2 region, encompassing RAI1 gene. Its clinical presentation is extremely variable, especially for what concerns the cognitive level and the behavioral phenotype. Such aspects, as well as the dysmorphic/malformative ones, have been covered by previous studies; otherwise neurological features have never been systematically described. In order to delineate the neurological phenotype of Potocki–Lupski Syndrome, we collect an 8‐patients cohort. Developmental milestones are delayed and a mild to moderate cognitive impairment is present in all patients, variably associated with features of autism spectrum disorder, behavioral disturb, and sleep disturb. Hypotonia appears a less frequent finding than what previously reported, while motor clumsiness/coordination impairment is frequent. EGG registration demonstrated a common pattern with excess of diffuse rhythmic activity in sleep phases or while the patient is falling asleep. Brain MRI did not reveal common anomalies, although unspecific white matter changes may be present. We discuss such findings and compare them to literature data, offering an overview on the neurological and cognitive‐behavioral presentation of the syndrome.  相似文献   
43.
Pneumocystis carinii f. sp. hominis isolates from 207 clinical specimens from nine countries were typed based on nucleotide sequence variations in the internal transcribed spacer regions I and II (ITS1 and ITS2, respectively) of rRNA genes. The number of ITS1 nucleotides has been revised from the previously reported 157 bp to 161 bp. Likewise, the number of ITS2 nucleotides has been changed from 177 to 192 bp. The number of ITS1 sequence types has increased from 2 to 15, and that of ITS2 has increased from 3 to 14. The 15 ITS1 sequence types are designated types A through O, and the 14 ITS2 types are named types a through n. A total of 59 types of P. carinii f. sp. hominis were found in this study.  相似文献   
44.
We recently set up a gamma interferon (IFN-γ) enzyme-linked immunospot assay (ELISPOT), using selected early secreted antigenic target 6 (ESAT-6) peptides, that appears specific for active tuberculosis (A-TB). However, ELISPOT is difficult to automate. Thus, the objective of this study was to determine if the same selected peptides may be used in a technique more suitable for routine work in clinical laboratories, such as whole-blood enzyme-linked immunosorbent assay (WBE). For this purpose, 27 patients with A-TB and 41 control patients were enrolled. Our WBE, using the already described selected peptides from ESAT-6 plus three new ones from culture filtrate protein 10, was performed, and data were compared with those obtained by ELISPOT. Using our selected peptides, IFN-γ production, evaluated by both WBE and ELISPOT, was significantly higher in patients with A-TB than in controls (P < 0.0001). Statistical analysis showed a good correlation between the results obtained by WBE and ELISPOT (r = 0.80, P < 0.001). To substantiate our data, we compared our WBE results with those obtained by QuantiFERON-TB Gold, a whole-blood assay based on region of difference 1 (RD1) overlapping peptides approved for TB infection diagnosis. We observed a slightly higher sensitivity with QuantiFERON-TB Gold than with our WBE (89% versus 81%); however, our test provided a better specificity result (90% versus 68%). In conclusion, results obtained by WBE based on selected RD1 peptides significantly correlate with those generated by ELISPOT. Moreover, our assay appears more specific for A-TB diagnosis than QuantiFERON-TB Gold, and thus it may represent a complementary tool for A-TB diagnosis for routine use in clinical laboratories.  相似文献   
45.
The encounter of NK cells with dendritic cells (DC) undergoing maturation may result in the induction of NK cell proliferation. Whether such proliferation involves most NK cells or just a subset has yet to be determined. In the present study we analyzed the nature of such proliferating NK cells by combining carboxyfluorescein succinimidyl ester staining and double-fluorescence cytofluorimetric analysis. Freshly isolated peripheral blood NK cells cultured with LPS and immature DC underwent proliferation; however, proliferating cells were confined to a minor NK cell subset. This subset is characterized by the CD56(bright)CD16(-)NKG2A(+)KIR(-) surface phenotype (KIR, killer Ig-like receptor). This was further confirmed by the fact that, after cell sorting, only the CD56(bright) NK cells were able to proliferate in response to the DC stimulus, whereas the CD56(dull) were not. We also provide evidence that the CD56(bright) subset is the main source of IFN-gamma-producing NK cells, upon interaction with DC. The CD56(bright)CD16(-) NK cells express a panel of surface molecules including CD62L, CCR7 and CXCR3 that may allow their homing either to secondary lymphoid compartments or to inflamed tissues. This implies that, in vivo, the interactions between DC undergoing maturation and CD56(bright) NK cells may occur in different tissues and have different functional implications.  相似文献   
46.
OBJECTIVE: Elevation of blood pressure and heart rate increase the risk of cardiovascular disease. Administration of estrogens does not affect heart rate but may decrease 24 h blood pressure. In this study, we tested the effect of the estro-progestogenic compound tibolone. METHODS: Thirty healthy, post-menopausal women were randomized to receive placebo (n = 15) or tibolone, at the commonly prescribed dose of 2.5 mg per day (n = 15). Before and after 6 months of treatment, in each woman blood pressure and heart rate were monitored every 30 min for 41 h by an ambulatory device. Valuable readings were those collected from 8:00 a.m. of the second day to 8:00 a.m. of third day. Analyses were performed of 24 h, day-time (7:00 a.m.-11:00 p.m.) and night-time (11:00 p.m.-7:00 a.m.) values. Day to night difference was also calculated. Results: Placebo did not modify 24h, day-time, and night-time blood pressure or heart rate values. Day-night differences were also not affected by placebo. Similarly to placebo, tibolone administration did not modify any of the blood pressure parameters taken into consideration. By contrast, a significant decline of 24 h heart rate (73.2 +/- 2.3 beats/min versus 69.3 +/- 1.7 beats/min; P < 0.0008) was observed. The effect was significant both at day (76.6 +/- 2.4 beats/min versus 72.1 +/- 1.9 beats/min; P < 0.0001) and night (65.8 +/ 2.6 beats/min versus 62.4 +/- 1.9 beats/min; P < 0.05). Day-night blood pressure and heart rate differences were not affected by tibolone. CONCLUSIONS: In post-menopausal women, administration of tibolone does not influence 24 h blood pressure but reduces heart rate.  相似文献   
47.
This research aimed to investigate the time course of the cortical activity level preceding spontaneous awakening as a function of age and state. Two groups of infants (1-4 and 9-14 weeks of age) were continuously monitored by polygraphic recording and behavioural observation during the night. The electroencephalographic (EEG) activity recorded by the C3-O1 lead was analysed through an automatic analysis method which provides, for each 30-s epoch, a single measure, time domain based, of the EEG synchronization. The EEG parameter values were computed in the 6 min preceding each awakening out of non-rapid eye movement (NREM) sleep and out of rapid eye movement (REM) sleep. The EEG background activity level did not change in the minutes preceding awakening out of REM sleep. Awakening out of NREM sleep was preceded by a change of EEG activity level in the direction of higher activation with different time course according to the age. Both REM and NREM sleep results suggest that a high level of EEG activity is a prerequisite for the occurrence of a spontaneous awakening.  相似文献   
48.
Summary The Southern blot hybridization technique has been applied to study the configuration of immunoglobulin and T-cell receptor genes in 6 cases of the so called mediastinal large cell lymphoma with sclerosis. This lymphoma has been recently recognized as a separate entity among non-Hodgkin lymphomas mainly affecting young adult patients. The B-cell origin of this neoplasm was suggested by means of immunohistochemical analysis. However, the immunophenotypical B-cell related markers used do not always exhibit lineage fidelity. The Southern blot analysis demonstrated the presence of unique heavy and k-light chain immunoglobulin gene rearrangements, establishing genotypically their B-cell origin.This work was supported by the Associazione Italiana per la Ricerca sul Cancro, Milano, Italy, and Progetto finalizzato Oncologia (contratto no 86.00461.44), CNR, Rome, Italy. Aldo Scarpa and Maurizio Lestani are supported by a Scholarship from the Associazione Italiana per la Ricerca sul Cancro, Milano, Italy  相似文献   
49.
 Regional cerebral blood flow changes related to the performance of two oculomotor tasks and a central fixation task were compared in ten healthy human subjects. The tasks were: (a) performance of fast-regular saccades; (b) performance of voluntary antisaccades away from a peripheral cue; (c) passive maintenance of central visual fixation in the presence of irrelevant peripheral stimulation. The saccadic task was associated with a relative increase in activity in a number of occipitotemporal areas. Compared with both the fixation and the saccadic task, the performance of antisaccades activated a set of areas including: the superior and inferior parietal lobules, the precentral and prefrontal cortex, the cingulate cortex, and the supplementary motor area. The results of the present study suggest that: (a) compared with self-determined saccadic responses the performance of fast regular, reflexive saccades produces a limited activation of the frontal eye fields; (b) in the antisaccadic task the inferior parietal lobes subserve operations of sensory-motor integration dealing with attentional disengagement from the initial peripheral cue (appearing at an invalid spatial location) and with the recomputation of the antisaccadic vector on the basis of the wrong (e.g., spatially opposite) information provided by the same cue. Received: 20 May 1996 / Accepted: 28 January 1997  相似文献   
50.
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