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排序方式: 共有2227条查询结果,搜索用时 15 毫秒
1.
Caterina Proto Daniela Romualdi Rosa Maria Cento Rosario S Spada Giuseppina Di Mento Raffaele Ferri Antonio Lanzone 《Gynecological endocrinology》2006,22(4):213-218
BACKGROUND: In the central nervous system, several neuropeptides are believed to be involved in the pathophysiology of Alzheimer's disease (AD). Indeed, previous studies have documented that glucagon-like peptide 1 (GLP-1) possesses neurotropic properties and can reduce amyloid-beta peptide levels in the brain in vivo. Moreover, the concentrations of neuropeptide Y (NPY) seem to be altered in the cerebrospinal fluid of patients with AD and in subjects with major depression. Finally, among the modifications induced by aging, a dysregulation of the ghrelin-growth hormone (GH) system has been reported. METHODS: We investigated the plasma concentrations of these neuropeptides in 14 subjects with AD. Data obtained from these patients were compared with data from an age- and weight-matched healthy group. RESULTS: No significant differences were found between the two groups in relation to plasma levels of GLP-1, NPY, ghrelin and GH. Peripheral NPY concentrations were positively correlated with ghrelin levels in both groups, and with plasma GLP-1 concentration only in controls. CONCLUSION: On the basis of our results, peripheral levels of these neuropeptides seem not to serve as biochemical markers of AD. 相似文献
2.
In vitro study of the antibacterial activity of ofloxacin against recent clinical isolates 总被引:1,自引:0,他引:1
The in vitro activity of ofloxacin, a new broad-spectrum antimicrobial agent, was studied by a standardized single disc method. A total of 990 clinical isolates were tested, including 20 strains of anaerobic bacteria. Ofloxacin was highly active against 683 strains (70.41%), had intermediate activity against 109 (11.23%) and had no activity against 178 (18.35%). Ofloxacin was highly active against E. coli, Klebsiella sp., Citrobacter sp., Proteus mirabilis, Proteus morganii, Salmonella sp., Campylobacter jejuni, Haemophilus influenzae, Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pneumoniae, Eubacterium sp., Propionibacterium acnes and Streptococcus sp. Pseudomonas sp., Serratia sp. and Proteus vulgaris had percentages of resistance to ofloxacin of 37.11%, 32% and 33.33% respectively. High percentages of resistance to ofloxacin were found only for Providencia sp., Proteus rettgeri and Bacteroides fragilis. With regard to Streptococcus faecalis, the results obtained with the disc procedure were not reliable and MIC determination was necessary to assess the behaviour of the drug. 相似文献
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5.
Claudio Babiloni Giuliano Binetti Emanuele Cassetta Gloria Dal Forno Claudio Del Percio Florinda Ferreri Raffaele Ferri Giovanni Frisoni Koichi Hirata Bartolo Lanuzza Carlo Miniussi Davide V Moretti Flavio Nobili Guido Rodriguez Gian Luca Romani Serenella Salinari Paolo M Rossini 《Clinical neurophysiology》2006,117(2):252-268
OBJECTIVE: The present study tested the hypothesis that cortical electroencephalographic (EEG) rhythms. change across normal elderly (Nold), mild cognitive impairment (MCI), and Alzheimer's disease (AD) subjects as a function of the global cognitive level. METHODS: Resting eyes-closed EEG data were recorded in 155 MCI, 193 mild AD, and 126 age-matched Nold subjects. EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10.5 Hz), alpha 2 (10.5-13 Hz), beta 1 (13-20 Hz), and beta 2 (20-30 Hz). EEG cortical sources were estimated by LORETA. RESULTS: Occipital delta and alpha 1 sources in parietal, occipital, temporal, and 'limbic' areas had an intermediate magnitude in MCI subjects compared to mild AD and Nold subjects. These five EEG sources presented both linear and nonlinear (linear, exponential, logarithmic, and power) correlations with the global cognitive level (as revealed by mini mental state examination score) across all subjects. CONCLUSIONS: Cortical EEG rhythms change in pathological aging as a function of the global cognitive level. SIGNIFICANCE: The present functional data on large populations support the 'transitional hypothesis' of a shadow zone across normality, pre-clinical stage of dementia (MCI), and AD. 相似文献
6.
Among 315 cases of parenchymal renal carcinoma resected between 1975 and 1985, 19 cases (6 per cent) of sarcomatoid carcinoma were identified. All patients were symptomatic or had a palpable mass in the flank at hospitalization. Tumor stage generally was advanced at operation and metastases were detected in 8 patients (Robson stage IV), all of whom died after an average postoperative survival of 8 months. In 3 patients there was tumor invasion of the renal vein (Robson stage IIIA), and they died after an average postoperative period of 11 months. Of 4 patients with perinephric fat invasion (Robson stage II) 2 died of cancer after an average survival of 15 months and 2 are alive with no evidence of disease for an average of 73 months postoperatively. In these later 2 cases the sarcomatoid areas constituted less than 5 per cent of the entire tumor and the remaining tumor was low grade carcinoma. In 3 patients adequate followup is not available and 1 was lost to followup. This histological variant of parenchymal cell carcinoma is a high grade malignancy with a poor prognosis. Operative treatment appears to be ineffective in modifying the behavior of the tumor. 相似文献
7.
Agenesis of common carotid artery is rare and no report of stenting procedures (carotid artery stenting) for associated stenosis of the internal carotid have been published. We report a case of internal carotid stenosis associated with this anomaly. A 73-year-old male with left internal carotid artery originating from the arch, with significant stenosis, was referred to us. Wallstent was deployed with success. Carotid artery stenting should be reserved to uncomplicated arch anatomy and plaques with low fragmentation risk. 相似文献
8.
M. Cioni I. Iero G. Tornatore A. Cocilovo A. Belfiore R. Ferri 《Neurological sciences》2007,28(2):100-103
Abstract We describe kinematics, kinetics and electromyographic patterns of a patient with spinal myoclonus of the left lower limb,
during walking. Gait analysis was performed when the patient was OFF and ON his treatment with antiepileptic drugs. When OFF,
we mainly observed clonic bursts and out-of-phase activations of m. tibialis anterior and m. rectus femoris, with increased
hip flexion, reduction of knee flexion during swing and excessive ankle dorsal flexion. Furthermore, large oscillations of
knee moment of force and power during stance phase were also observed. These abnormal patterns markedly recovered when ON
drugs. 相似文献
9.
In this work, the dosimetric characteristics of a new commercial carbon fiber treatment table are investigated. The photon beam attenuation properties of the Siemens image-guided radiation therapy (IGRT) tabletop were studied in detail. Two sets of dosimetric measurements were performed. In the first experiment a polystyrene slab phantom was used: the central axis attenuation and the skin-sparing detriment were investigated. In the second experiment, the off-axis treatment table transmission was investigated using a polystyrene cylindrical phantom. Measurements were taken at the isocenter for a 360° rotation of the radiation beam. Our results show that the photon beam attenuation of the Siemens IGRT carbon fiber tabletop varies from a minimum of 2.1% (central axis) to a maximum of 4.6% (120° and 240° beam incidence). The beam entrance dose increases from 82% to 97% of the dose at the depth of maximum for a clinical 6-MV radiation field. The depth of maximum also decreases by 0.4 cm. Despite the wedge cross section of the table the beam attenuation properties of the IGRT tabletop remain constant along the longitudinal direction. American Association of Medical Dosimetrists. 相似文献
10.
Chemiluminescence dot blot hybridization assay for detection of B19 parvovirus DNA in human sera. 总被引:5,自引:3,他引:2 下载免费PDF全文
M Musiani M Zerbini D Gibellini G Gentilomi S Venturoli G Gallinella E Ferri S Girotti 《Journal of clinical microbiology》1991,29(9):2047-2050
A chemiluminescence dot blot hybridization assay was used for the detection of B19 parvovirus DNA in human sera by using digoxigenin-labeled probes. The probes were revealed immunoenzymatically by use of anti-digoxigenin Fab fragments conjugated with alkaline phosphatase. The chemiluminescence signal was obtained by reacting the labeled probe-target complex with an enzyme-triggerable dioxetane substrate. The emitted photons were detected with instant photographic films. In the search for B19 parvovirus DNA, 2,808 serum samples were analyzed. 相似文献