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排序方式: 共有9086条查询结果,搜索用时 8 毫秒
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Paolo Mazzone Fabrizio Stocchi Salvatore Galati Angelo Insola Maria Grazia Altibrandi Nicola Modugno Domenicantonio Tropepi Livia Brusa Alessandro Stefani 《Neuromodulation》2006,9(3):221-228
Objectives. Traditional deep brain stimulation (DBS) at the subthalamic nucleus (STN) has proved to be efficacious on core Parkinsonian symptoms. However, very disabling l ‐dopa–induced abnormal involuntary movements (AIMs) and axial signs are slightly affected, suggesting that we target less conventional targets. Our candidates for DBS were the globus pallidus internus (GPi) plus the intralaminar thalamic complex (Pf or CM), given its extensive functional links with basal ganglia nuclei. Materials and Methods. The routine utilization of our innovative stereotactic apparatus allows us to implant, at the same time, both the CM‐Pf complex together with the GPi in six Parkinson disease patients. Both intraoperative and postoperative neurophysiologic assessments helped us recognize functional subregions while optimizing implantation of electrodes. Unified Parkinson disease rating scale (UPDRS) motor scores, AIMs, and freezing were carefully blindly evaluated for each condition. Results. A significant amelioration of UPDRS scores was achieved by simultaneous activation of both targets. CM‐Pf activation was only slightly effective in reducing rigidity and akinesia, but more efficacious on freezing. Not surprisingly, AIMs were peculiarly decreased by the activation of the permanent electro‐catheter in the posteroventral GPi. Conclusions. These findings confirm that, in selected patients, it is conceivable to target structures other than the conventional STN in order to maximize clinical benefit. 相似文献
3.
Non-invasive proportional assist and pressure support ventilation in patients with cystic fibrosis and chronic respiratory failure 总被引:12,自引:2,他引:10 下载免费PDF全文
BACKGROUND: Patients with advanced cystic fibrosis can benefit from non-invasive positive pressure ventilation (NPPV) for the treatment of acute decompensation as well as for the management of chronic respiratory failure. This study was undertaken to compare the physiological effects of non-invasive proportional assist ventilation (PAV) and pressure support ventilation (PSV) on ventilatory pattern, transcutaneous blood gas tensions, and diaphragmatic effort in stable patients with cystic fibrosis and chronic CO2 retention. METHODS: In 12 patients two periods of spontaneous breathing were followed randomly by PSV (12 (3) cm H2O) and PAV (flow assist 4.9 (1.3) cm H2O/l.s, volume assist 18.9 (5.1) cm H2O/l) set for the patient's comfort and administered for 40 minutes with 2 cm H2O continuous positive airway pressure. Ventilatory pattern, transcutaneous blood gas tensions, and surface diaphragmatic electromyography were measured in the last 10 minutes of each application. RESULTS: On average, both PSV and PAV improved ventilation (+30%), tidal volume (+30%), and transcutaneous CO2 (-7%) while reducing diaphragmatic activity (-30% with PSV, -20% with PAV). Mean inspiratory airway pressure was lower during PAV than during PSV (9.7 (1.9) and 12.9 (2.7) cm H2O, respectively; p<0.05). The mean coefficient of variation of tidal volume was about 20% (range 11-39%) during spontaneous breathing and did not change with either PAV or PSV. CONCLUSIONS: These results show that short term administration of nasal PAV and PSV to patients with stable cystic fibrosis with chronic respiratory insufficiency is well tolerated, improves ventilation and blood gas tensions, and unloads the diaphragm. 相似文献
4.
Lucio Posteraro Fabrizio Pezzoni Emilio Varalda Gloria Fugazza Anna Mazzucchi 《Journal of neurology》1991,238(6):337-339
Summary A patient who developed a unilateral opercular syndrome following a cerebrovascular accident is described. Computed tomography showed that the lesion did not affect the opercular cortex, but involved deep white matter and the head of the caudate nucleus of the left hemisphere. Persistent hypophonia and transient aphasia were associated. Comparison with previous cases is discussed. 相似文献
5.
G Fitze J Cramer A Serra M Schreiber D Roesner H K Schackert 《Zeitschrift für Kinderchirurgie》2003,13(3):152-157
Hirschsprung disease (HSCR) is considered a model for a complex inheritance disorder. Several genes, including the major HSCR-susceptibility RET proto-oncogene, play an aetiological role in the development of HSCR. Genetic linkage analysis in familial HSCR with both long- and short-segment phenotypes has demonstrated a tight linkage to the RET locus, while the phenotype within a HSCR family is characterised by an incomplete penetrance or a variable extension of the aganglionosis. Therefore, additional genetic alterations of RET are postulated in the aetiology or modification of the HSCR phenotype. In this study, the coding region of all 21 exons of the RET proto-oncogene, including the flanking intronic sequences, were investigated by direct DNA sequencing in a HSCR population. We genotyped the c.135 G/A polymorphism and resolved haplotypes comprising the mutation locus and the c.135 G/A polymorphism. Twenty different mutations were detected in 18 of 76 HSCR patients. In ten families the mutations were inherited from the parents, while only four patients had a positive family history for the disease. Moreover, in all ten families an incomplete penetrance of the HSCR phenotype was observed. We have investigated the effect of the non-mutated wild-type allele as well as the c.135 G/A polymorphism on the phenotype within the HSCR families. Our findings support the notion that both RET alleles are involved in the pathogenesis of a subgroup of HSCR patients in a dose-dependent fashion. Additionally, we have shown a modifying effect of the c.135 G/A polymorphism on the HSCR phenotype within HSCR families. 相似文献
6.
γδ T lymphocytes respond to different bacterial antigens and transformed cells. The antigenic molecules responsible for this activity have been studied extensively in antigenic preparations from Mycobacterium . We describe here the in vitro effect of Pseudomonas aeruginosa on γδ T lymphocytes and the properties of the implicated compounds. We found a preferential γδ T-cell expansion when we used heat-treated P. aeruginosa preparations and a dose-dependent inhibition of proliferation of peripheral blood mononuclear cells (PBMC) when non-heat-treated antigens were studied. This expansion corresponded to a Vγ9-positive subpopulation. In contrast to αβ T lymphocytes, the highest stimulatory activity was restricted to very small cytosolic compounds. This activity was protease resistant and phosphatase sensitive and always dependent on interleukin (IL)-2 or αβ T-cell activation. We concluded that the antigenic molecules from P. aeruginosa that activated γδ T lymphocytes were small, non-peptidic, phosphorylated compounds, similar to those previously described from Mycobacterium . 相似文献
7.
8.
Salvatore Serra Giuliana Brunetti Giovanni Vacca Carla Lobina Mauro A M Carai Gian Luigi Gessa Giancarlo Colombo 《Alcohol》2003,29(2):101-108
Results of a recent study have demonstrated that exposure to multiple ethanol concentrations and repeated ethanol deprivation periods in Indiana ethanol-preferring (P) rats resulted in the development of an alcohol deprivation effect (ADE; the temporary increase in voluntary ethanol intake after a period of deprivation from ethanol) characterized by consumption of intoxicating amounts of ethanol. The current study was designed to possibly extend these results to Sardinian alcohol-preferring (sP) rats, generated with the same selective program previously used for P rats. To this aim, ethanol-naive sP rats were exposed initially to the home cage four-bottle choice [10%, 20%, and 30% (vol./vol.) ethanol solutions and water] for eight consecutive weeks. Subsequently, rats were divided into two groups: The first group had continuous access to the four-bottle regimen (nondeprived rats), and the second group was exposed to five cycles of 14-day periods of deprivation from ethanol and 14-day periods of reexposure to the four-bottle regimen. An ADE developed after each deprivation period. However, the extra intake of ethanol was limited to the first hour of each reaccess period. Magnitude of ADE did not change with repeated periods of deprivation. However, a shift in preference toward the two highest concentrations of ethanol solutions was evident from the first reexposure to ethanol and was maintained throughout the study. These results provide further evidence on the heterogeneity of ethanol-drinking behavior among rat lines selectively bred for high ethanol preference and consumption. 相似文献
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10.
Empty Sella and Headache 总被引:2,自引:0,他引:2
Teresa Catarci Fabrizio Fiacco Luigi Bozzao Manuela Pati Alice Valeria Magiar Rosanna Cerbo 《Headache》1994,34(10):583-586
SYNOPSIS
Empty sella is an anatomical condition caused by herniation of the subarachnoid space into the pituitary fossa through an incompetent seller diaphragm. Headache seems to be one of the most frequently reported symptoms. We studied 13 headache patients (12 females, 1 male) presenting with primary empty sella (PES) on CT scan. The characteristics of the headache were analyzed and plasma levels of pituitary hormones or cortisol assessed. We confirmed the nonspecific nature of the headache in PES even though the majority of our patients complained of daily headache, mostly localized anteriorly. Hormone plasma levels were within normal range in all the patients assessed. However, four patients reported earlier endocrine disorders and more than half of the patients presented with obesity.
In our opinion, PES should be suspected in middle-aged overweight women with daily headache even in the absence of endocrine symptomatology. 相似文献
Empty sella is an anatomical condition caused by herniation of the subarachnoid space into the pituitary fossa through an incompetent seller diaphragm. Headache seems to be one of the most frequently reported symptoms. We studied 13 headache patients (12 females, 1 male) presenting with primary empty sella (PES) on CT scan. The characteristics of the headache were analyzed and plasma levels of pituitary hormones or cortisol assessed. We confirmed the nonspecific nature of the headache in PES even though the majority of our patients complained of daily headache, mostly localized anteriorly. Hormone plasma levels were within normal range in all the patients assessed. However, four patients reported earlier endocrine disorders and more than half of the patients presented with obesity.
In our opinion, PES should be suspected in middle-aged overweight women with daily headache even in the absence of endocrine symptomatology. 相似文献