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21.
Davicino Roberto Patricia Micucci Turner Sebastian Ferraro Graciela Claudia Anesini 《Basic & clinical pharmacology & toxicology》2010,106(1):38-44
Abstract: Limonene is a monoterpene present in citrus fruit and is used as flavouring agents of foods. It was shown that monoterpenes possess antioxidant activity. Previously, it was demonstrated that limonene exerts anti‐proliferative action on a lymphoma cell line without modifying normal lymphocyte viability. H2O2 has a modulator role in cell proliferation. In the present study, the effect of limonene on normal lymphocytes proliferation and its relation with H2O2 level modulation was analysed, evaluating its effect on the activity of cell antioxidant enzymes, such as catalase, peroxidase and superoxide dismutase. Limonene exerted a biphasic effect on cell proliferation; the increase in cell proliferation was related to the decrease in H2O2 level by the increase in catalase and peroxidase activities. Moreover, limonene protected the cells to the oxidative stress induced by exogenous addition of H2O2. In view of these results, it is possible that limonene could protect normal lymphocytes from diseases related to oxidative stress, including cancer, but further research is necessary to establish the role of limonene as a potential antioxidant that can effectively protect lymphocytes from oxidative stress and mitochondrial dysfunction. 相似文献
22.
Eugenia Arias Horacio Martinetto Marcelo Schultz Sebastian Ameriso Santiago Rivera Oscar Lossetti Gustavo Sevlever 《Diagnostic molecular pathology》2006,15(3):174-179
A polymerase chain reaction (PCR) method for the detection of the glmM gene, selected as Helicobacter pylori target sequence, was improved. While performing pathogenicity island cagA gene detection to discriminate pathogenic strains in atherosclerotic carotid samples, several cagA-positive but glmM-negative samples were found. Polymorphisms present in the region amplified in the nested PCR reaction could explain this result; primers were therefore designed to perform a seminested reaction; this modification optimized sensitivity while maintaining specificity. A real-time PCR for Helicobacter DNA detection was also setup. The combination of all 4 PCR reactions detected 83% of H. pylori DNA-positive samples in atherosclerotic carotid tissue, 64% of which were cagA gene positive. 相似文献
23.
Accelerating cardiac cine 3D imaging using k-t BLAST. 总被引:1,自引:0,他引:1
Sebastian Kozerke Jeffrey Tsao Reza Razavi Peter Boesiger 《Magnetic resonance in medicine》2004,52(1):19-26
By exploiting spatiotemporal correlations in cardiac acquisitions using k-t BLAST, gated cine 3D acquisitions of the heart were accelerated by a net factor of 4.3, making single breathhold acquisitions possible. Sparse sampling of k-t space along a sheared grid pattern was implemented into a cine 3D SSFP sequence. The acquisition of low-resolution training data, which was required to resolve aliasing in the k-t BLAST method, was either interleaved into the sampling process or obtained in a separate prescan to allow for shorter breathhold durations in patients with heart disease. Volumetric datasets covering the heart with 20 slices at a spatial resolution of 2 x 2 x 5 mm3 were recorded with 20 cardiac phases in a total breathhold duration of 25-27 sec, or 18 sec if partial Fourier sampling was additionally employed. The feasibility of the method was demonstrated on healthy volunteers and on patients. The comparison of endocardial area derived from single slices of the 3D dataset with values extracted from separate single-slice acquisitions showed no significant differences. By shortening the acquisition substantially, k-t BLAST may greatly facilitate volumetric imaging of the heart for evaluation of regional wall motion and the assessment of ventricular volume and ejection fraction. 相似文献
24.
Mark L. Kraus Judith S. Weis Peddrick Weis 《Archives of environmental contamination and toxicology》1988,17(3):355-363
Tolerance to mercury in two populations of the grass shrimpPalaemonetes pugio was examined at different stages of this animal's life cycle. One population came from a mercury-contaminated creek, Piles Creek (PC), near industrialized Linden, New Jersey. The other population came from a relatively clean area, Big Sheepshead Creek (BSC), near non-industrialized Tuckerton, New Jersey. Larval grass shrimp showed no significant difference between populations in terms of mortality in 0.01 mg/L HgCl2, although treated BSC larvae metamorphosed significantly (P < 0.05) more slowly than their respective control group. While no BSC larvae survived the 0.0125 mg/L methylmercuric chloride (meHg) treatment, PC larvae exposed to 0.0125 mg/L meHg survived as well as their controls, indicating enhanced tolerance to meHg in this population.Adult shrimp were exposed for 14 days to control, 0.025 mg/L meHg, 0.025 mg/L HgCl2, 0.05 mg/L meHg, or 0.05 mg/L HgCl2 PC shrimp were significantly (P < 0.05) more tolerant to both 0.025 mg/L meHg, and 0.025 mg/L HgCl2 than were the BSC adults.Polyacrylamide gel electrophoresis suggests that both populations of shrimp are capable of producing a metallothionein like protein (MT) in response to treatment with HgCl2; MT is found in higher levels in field-caught PC shrimp than in field-caught BSC shrimp. MT was not present in field-collected, viable eggs from either population. 相似文献
25.
Andreas Büttner Bilge Bavbek Peter A. Winkler Parviz Mehraein Serge Weis 《Neuropathology》1997,17(2):94-100
The clinical, radiological, and pathological features in 10 cases of ganglioglioma are described. The clinical data were derived from the patients' medical records, including a review of the age, sex, details of the presenting symptoms, radiological imagings, surgical intervention, and the clinical outcome. Age ranged from 1 to 66 years (mean 29); there were five males and five females. The tumors were located in the fronto-medial, bifrontal, temporal, temporo-basal, temporo-parieto-occipital, and parietal lobes; the 3rd ventricle; the cervicothoracic spinal cord; and the conus medullaris. The presenting symptoms were focal seizures, headaches, hemiparesis, paraparesis, and tetraparesis. In four patients, gross total resection was achieved and in the remaining six patients only subtotal resection was possible. Tumor recurrence occurred in three patients, 1 year, 14 months, and 2 years after the first operation. The histopathologic appearance of gangliogliomas showed a broad variation of the neuronal, glial, and stromal component. Studying proliferation characteristics, labeling for Ki-67 ranged from 0 to 13.7% (mean 4.1) and for PCNA from 0 to 32.1% (mean 20.4). Due to their favorable prognosis, early recognition and correct diagnosis are important in order to avoid progressive neurological deficits and unnecessary aggressive therapy. The application of immunohistochemistry for both neuronal (synaptophysin, NSE, NFP) and astrocytic (GFAP) cell markers, as well as proliferation markers, are recommended in the diagnostic setting for gangliogliomas. The treatment of choice is total surgical resection. The role of radio- and chemotherapy is still controversial. 相似文献
26.
W W Loney B J Kudchodkar S Weis M B Clearfield J Shores A G Lacko 《American journal of therapeutics》1997,4(9-10):301-309
Subjects with high-density lipoprotein cholesterol (HDL-C) values of less than 47 mg/dL (mean 35.6 +/- 5.5 mg/dL) were selected for this study to examine relationships between plasma lipids, lipoprotein components, and the outcome of gemfibrozil therapy. Changes in plasma lipoprotein subfractions were determined to better understand the previously observed variability of the responses in both HDL-C and triglycerides to gemfibrozil. Based on the data collected, an attempt was made to identify pretreatment lipid parameters that may be predictive regarding the efficacy of gemfibrozil therapy. Serum samples were analyzed at the outset and after the conclusion of 12 weeks of gemfibrozil therapy. Because the HDL-C response to therapy was highly variable, the data from patients were separated into two groups, responders (>20% increase in HDL-C) and nonresponders (<20% increase in HDL-C). The lipid components of lipoprotein subfractions were evaluated using multiple regression analysis yielding predictive models that show the relationship between specific lipoprotein subfractions and the percentage change in HDL-C and posttreatment triglyceride levels. Group classification was then predicted with 78% accuracy using specific lipoprotein subfractions to estimate an individual's percentage change in HDL-C. The major difference between the responder and nonresponder groups was their respective correlations between triglyceride-lowering and changes in HDL-C. In the responder group, there was a significant correlation between the changes in HDL-C and the lowering of triglycerides (r = 0.61, p = 0.03), whereas the nonresponder group showed no such correlation (r = 0.17, p = 0.52). The predictive model also proved to be highly accurate in forecasting the effectiveness of the triglyceride-lowering action of gemfibrozil in this group of patients. 相似文献
27.
Othman Shibly Robert E. Schifferle Sebastian G. Ciancio Majd Tarakji Maryanne L. Mather 《Journal of clinical periodontology》1997,24(4):260-263
Abstract A single blind 30 day study compared the reduction of plaque and gingivitis for the Hapika® Powerbrush to the Interplak® ultra 10 tuft. A longitudinal parallel group design was utilized and screening evaluation was performed to determine patient eligibility prior to study enrollment. 66 subjects were entered into the study and assigned to 1 of 2 groups, each using one of the toothbrushes. At baseline, subjects received an oral soft tissue exam, a dental hard tissue exam, and were scored by the Lobene modification of the Löe and Silness gingival index (GI). Plaque was then disclosed and scored both pre and post brushing using the modified Turesky plaque/debris examination and an interproximal bleeding examination was performed post-brushing. On days 15 and 30, after an oral soft tissue and GI examination, plaque was graded by the Modified Turesky plaque/debris exam. Subjects then brushed and were graded by the Modified Turesky plaque/debris examination and an interproximal bleeding index examination. The results showed that both brushes provided a similar change in clinical indices. All produced a statistically significant reduction from baseline to day 30 for the gingival index (26.5-29.1%), the bleeding index (13.8-24.1%), and the plaque index (16.9-19.4%), A comparison of pre and post brushing scores for the plaque index at 30 showed that both brushes reduced plaque similarly with a statistically significant reduction (P<0.05) from their pre-brushing plaque index scores at all time periods. 相似文献
28.
Edward Golec Sebastian Nowak Roman Go?dzialski Micha? Godyń 《Chirurgia narzadów ruchu i ortopedia polska》2003,68(3):185-189
In this paper the authors evaluate the long-term results of treatment for articular calcaneus fractures with Westhues method. This evaluation is performed with regard to triple measurement of B?hler's angle value and to subjective criteria. The clinical material from years 1985-2002 consists of 47 patients aged between 24 and 56 years (mean age 32 years) with articular calcaneus fractures--namely, 41 male patients (87.2%) and 6 female patients (12.8%). The follow-up examination was performed in 24 patients (51% of all patients), namely, in 23 male patients (48.8%) and in one female patient (2.2%). Minimum follow-up time was 12 months and maximum was 9 years. Acquired results suggest that Westhues method restores normal B?hler's angle value only in tongue-type calcaneous fractures. 相似文献
29.
Venöse Thromboembolien (VTE) stellen eine häufige Morbiditäts- und Mortalitätsursache dar; die jährliche Inzidenz wird mit etwa 1 : 1 000 angegeben. Dabei sind verschiedene Risikogruppen zu unterscheiden, die sowohl durch endogene Faktoren (z. B. genetisch deteminierte Thrombophilie), viel häufiger aber durch exogene Faktoren (zugrundeliegende Erkankung) charakterisiert werden. Diese Heterogenität resultiert in Besonderheiten bei Prophylaxe und Therapie von VTE, auf die in dieser Darstellung eingegangen werden soll. 相似文献
30.
Is neurogenesis reparative after status epilepticus? 总被引:1,自引:0,他引:1