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排序方式: 共有1714条查询结果,搜索用时 46 毫秒
1.
Case report 506 总被引:1,自引:0,他引:1
F. Bertoni M.D. V. Zucchi M.D. S. Mapelli M.D. P. Bacchini M.D. 《Skeletal radiology》1988,17(7):522-526
2.
Flavio Masi Benedetta Leggio Giulio Nanni Simona Scheggi M Graziella De Montis Alessandro Tagliamonte Silvia Grappi Carla Gambarana 《Neuropsychopharmacology》2003,28(4):683-693
Long-term acetyl-L-carnitine (ALCAR) administration prevents the development of escape deficit produced by acute exposure to unavoidable stress. However, it does not revert the escape deficit sustained by chronic stress exposure. Rats exposed to chronic stress show a low dopamine (DA) output in the nucleus accumbens shell (NAcS) and do not acquire an appetitive behavior sustained by the earning of vanilla sugar (VS) made contingent on the choice of one of the two divergent arms of a Y-maze (VS-sustained appetitive behavior, VAB), while control rats consistently do. The present study shows that ALCAR treatment in rats exposed to a 7-day stress protocol prevented a decrease in DA output in the NAcS and medial prefrontal cortex (mPFC) of rats, and that it strengthened the DA response to VS consummation in the same two areas. Moreover, rats treated with long-term ALCAR or exposed to chronic stress while treated with ALCAR acquired VAB as efficiently as control rats. Moreover, VAB acquisition in stressed rats treated with ALCAR coincided with the reversal of the deficits in escape and in dopaminergic transmission in the NAcS. Thus, repeated ALCAR treatment preserved the DA response to VS in chronically stressed rats and this effect appeared to be predictive of the rat's competence to acquire VAB. 相似文献
3.
Ricca V Nacmias B Boldrini M Cellini E di Bernardo M Ravaldi C Tedde A Bagnoli S Placidi GF Rotella CM Sorbi S 《Neuroscience letters》2004,365(2):92-96
Various studies have evaluated the possible role of the -1438G/A polymorphism within the 5-HT2A receptor gene in the susceptibility to Eating Disorders (EDs). One hundred and forty-eight ED patients (EDp) and 89 control subjects were interviewed by means of the Eating Disorder Examination (EDE) and analyzed for distribution of the -1438G/A polymorphism. Patients with the AA genotype suffering from Anorexia Nervosa and Bulimia Nervosa showed higher Weight and Shape Concern (P = 0.003 and P = 0.010, respectively) scores and greater overall severity of the ED psychopathology (EDE total score) (P = 0.012). The obtained preliminary data suggest the use of dimensional psychopathological measures in ED genetic studies. 相似文献
4.
Comparative Evaluation of Ligation-Mediated PCR and Spoligotyping as Screening Methods for Genotyping of Mycobacterium tuberculosis Strains 总被引:3,自引:0,他引:3
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Stefano Bonora M. Cristina Gutierrez Giovanni Di Perri Francesca Brunello Benedetta Allegranzi Marco Ligozzi Roberta Fontana Ercole Concia Veronique Vincent 《Journal of clinical microbiology》1999,37(10):3118-3123
Spoligotyping has been suggested as a screening test in multistep genotyping of Mycobacterium tuberculosis strains. Relying on restriction fragment length polymorphism (RFLP) analysis with IS6110 (IS6110 RFLP analysis) as a "gold standard," we performed a comparative evaluation of spoligotyping and ligation-mediated PCR (LMPCR), a recently described PCR-based typing method, as rapid screening tests for fingerprinting of 158 M. tuberculosis strains collected in Verona, Italy. LMPCR seemed to be comparable to spoligotyping in terms both of feasibility with rapidly extracted DNA and of generation of software-analyzable images. Moreover, LMPCR grouped considerably fewer strains than spoligotyping (38 versus 67%) and was found to reduce the cluster overestimation rate (26.3 versus 58%) and to give a better discriminatory index (0.992 versus 0.970) compared to spoligotyping. In our geographical region, where there was no evidence of clustered strains carrying fewer than six IS6110 copies, LMPCR was found to be more discriminatory than spoligotyping. We also evaluated two models of three-step typing strategies, involving the use of spoligotyping and LMPCR as screening methods and IS6110 RFLP analysis as a further supporting test. LMPCR proved to be a more effective first-step test than spoligotyping, significantly reducing the need for subtyping. LMPCR should be considered an alternative to spoligotyping as a rapid screening method for M. tuberculosis fingerprinting, particularly in areas with a low prevalence of M. tuberculosis strains carrying few copies of IS6110. 相似文献
5.
The long pentraxin PTX3 up-regulates tissue factor in activated monocytes: another link between inflammation and clotting activation 总被引:4,自引:0,他引:4
Napoleone E di Santo A Peri G Mantovani A de Gaetano G Donati MB Lorenzet R 《Journal of leukocyte biology》2004,76(1):203-209
Pentraxin-3 (PTX3), an acute-phase protein that belongs to the family of the PTXs, is found elevated in septic shock and increased in patients with acute myocardial infarction. As tissue factor (TF) plays a key role in thrombosis and inflammation associated with atherosclerosis and as we have recently reported that PTX3 increases TF synthesis in endothelial cells, we tested whether PTX3 could modulate TF expression in monocytes. Monocytes from peripheral blood of healthy donors were incubated with highly purified PTX3 with or without lipopolysaccharide (LPS). Cells were then disrupted, and procoagulant activity was assessed by a one-stage clotting time. PTX3 enhanced TF activity and antigen from LPS-stimulated monocytes in a dose-dependent way. The effect was specific, as other PTXs, such as C-reactive protein and serum amyloid P component, were ineffective. Moreover, the increase in activity was specific for LPS, as in the presence of other TF-inducing agents such as interleukin-1beta and tumor necrosis factor alpha, PTX3 was not effective. The increase in TF activity requires mRNA synthesis, as assessed by polymerase chain reaction. The mechanism by which PTX3 modulates TF synthesis resides in an enhanced IkappaB, alpha phosphorylation and degradation and increased migration of the transacting factor c-Rel/p65 into the nucleus, as determined by Western blot and electro-mobility shift assay. These results show that PTX3 is an enhancer of the expression of TF by mononuclear cells. In the area of vascular injury, during the inflammatory response, cell-mediated fibrin deposition takes place. PTX3 increases TF expression, thus potentially playing a role in thrombogenesis and wound healing. 相似文献
6.
Alessandro Finazzi-Agrò Giovanni Floris Maria Benedetta Fadda Carlo Crifò 《Inflammation research》1979,9(3):244-247
Various drugs were tested as inhibitors of diamine oxidase on the basis of chemical relationships to the enzyme substrates.It was found that serotonine tryptamine and phenformin are good competitive inhibitors while cimetidine and pheniprazine are non-competitive inhibitors. Other antihistaminic drugs like promethazine are less powerful inhibitors. 相似文献
7.
Pucciarelli HM Orden AB Cesani MF Oyhenart EE Muñe MC Zucchi M 《Growth, development, and aging : GDA》2002,65(2):83-93
An experiment on rat undernutrition through seven generations was performed in order to see: (1) whether the nutritional stress on growth increases from one generation to the next, and (2) if an equilibrium point (AFP) in which the RFI--the amount of food intake (mg) per gram of body weight--reached is the same in both control and undernourished animals. The RFI values were calculated for each generation, between the 30th and 100th days of age. A moderate undernutrition was applied to the seven generations (F1 to F7) following the parental (P) one, which acted as controls. Undernourishment was made from conception to the end of the experiment (100 days old). The RFI values diminished with the age increment and increased through generations. There was, however, a clear AFP of 75.9 +/- 3.5 mg/g at 100 days of age in males, and of 78.7 +/- 4.2 mg/g at 90 days of age in females. A clear cumulative increment of RFI through the filial generations was also found at intermediate growth ages. The frequently argued nongenetic transmission of the nutritional deficiencies from parents to descendants was corroborated with the present results. Such cumulative effect was evident at ages before the AFP was reached; i.e., when the decrement in body mass of the undernourished animals was not yet equilibrated with the amount of available nutrients. 相似文献
8.
Giulia Barcia Marlne Rio Zahra Assouline Coralie Zangarelli Charles-Joris Roux Pascale de Lonlay Julie Steffann Isabelle Desguerre Arnold Munnich Jean-Paul Bonnefont Nathalie Boddaert Agns Rtig Metodi D. Metodiev Benedetta Ruzzenente 《European journal of human genetics : EJHG》2021,29(3):533
Mitochondrial translation is essential for the biogenesis of the mitochondrial oxidative phosphorylation system (OXPHOS) that synthesizes the bulk of ATP for the cell. Hypomorphic and loss-of-function variants in either mitochondrial DNA or in nuclear genes that encode mitochondrial translation factors can result in impaired OXPHOS biogenesis and mitochondrial diseases with variable clinical presentations. Compound heterozygous or homozygous missense and frameshift variants in the FARS2 gene, that encodes the mitochondrial phenylalanyl-tRNA synthetase, are commonly linked to either early-onset epileptic mitochondrial encephalopathy or spastic paraplegia. Here, we expand the genetic spectrum of FARS2-linked disease with three patients carrying novel compound heterozygous variants in the FARS2 gene and presenting with spastic tetraparesis, axial hypotonia and myoclonic epilepsy in two cases.Subject terms: Metabolic disorders, Mutation 相似文献
9.
Macchi C Popolizio A Casamorata F Bicchi S Pieroni A Molino Lova R Miniati B Gulisano M Catini C Conti AA Gensini GF 《Italian journal of anatomy and embryology = Archivio italiano di anatomia ed embriologia》2002,107(2):93-97
Fifty-four subjects, aged between 20 and 35 years, divided into two subgroups, respectively 30 healthy subjects (17 males and 13 females) and 24 subjects with "gonalgia sine materia" (13 males and 11 females) underwent isokinetic exercise test in order to compare their dominant limb with the not dominant one as regard as the strength of extensor and flexor muscles of the knee. No statistically significant difference was found in any of the studied parameters in the comparison between the dominant limb and the not dominant one, both within the subgroup of healthy subjects and within the subgroup of subjects with "gonalgia sine materia". Authors conclude that psychological features may play a preeminent role in the genesis, as well as in the maintenance of "gonalgia sine materia", thus confirming previous data available in medical literature. 相似文献
10.
Simona Di Terlizzi Elisabetta Zino Benedetta Mazzi Chiara Magnani Cristina Tresoldi Serena Kimi Perna Marco Bregni Silvano Rossini Fabio Ciceri Claudio Bordignon Chiara Bonini Katharina Fleischhauer 《Biology of blood and marrow transplantation》2006,12(1):95-101
Minor histocompatibility antigens (mHags) HA-1 and HA-2 are encoded by biallelic loci, with immunogenic variants, HA-1H and HA-2V, which induce strong HLA-A2-restricted alloreactive T-cell responses, and nonimmunogenic counterparts, HA-1R and HA-2M, which represent functional null alleles that are poorly presented by HLA class I molecules. HA-1 and HA-2 are potential targets of selective graft-versus-leukemia and graft-versus-tumor reactivity after allogeneic hematopoietic stem cell transplantation (HSCT); however, these applications are restricted to a limited number of patients. Here, we show that a far more frequent application of HA-1 and HA-2 disparity relies on their use as markers for the state of host chimerism after allogeneic HSCT. We have determined allelic frequencies of 29.3% and 70.7% for HA-1H and HA-1R, respectively, and of 83.7% and 16.3% for HA-2V and HA-2M, respectively, in >200 healthy individuals from northern Italy. Similar frequencies were observed in nearly 100 patients affected by hematologic malignancies or solid tumors, thus showing that HA-1 and HA-2 variability are not associated with the presence of cancer. On the basis of these data, we predict that HA-1 and HA-2 can be used in 32.8% and 23.5% of Italian transplant patients, respectively, as markers for the state of host chimerism, whereas exploitation of disparity for these mHags for targeted immunotherapy will be possible in 10.7% and 1.1% of Italian patients, respectively. Retrospective HA-2 typing of bone marrow aspirates obtained from a patient during complete remission or recurrence of acute myeloid leukemia after haploidentical HSCT showed the feasibility of using HA-2 as a surrogate marker for disease monitoring. Because of an apparent north-south gradient for HA-1 allelic frequencies, with higher frequencies for the HA-1H variant reported in white populations from Southern Europe as compared with Northern Europe and North America, the diagnostic applicability of HA-1 disparity will be slightly more frequent in transplant patients from the north. Taken together, our data show that determination of HA-1 and HA-2 variability can be an important parameter for the selection of allogeneic stem cell donors, in particular for patients affected by hematologic malignancies without a tumor-specific molecular marker. 相似文献