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11.
Russo P Persegani C Papeschi LL Nicolini M Trimarchi M 《The International journal of neuroscience》1999,100(1-4):29-37
The present study examined sex differences in hemisphere preference (HP) assessed by the Preference Test (PT). This instrument is designed to measure the extent to which normal subjects rely on right-hemisphere or left-hemisphere cognition. Factor analysis on the total sample (N=1,057; 473 men and 584 women) revealed a clear two-factor structure (i.e., left-HP and right-HP), although separate analyses for men and women suggest that this structure is more straightforward in men than in women. The main differences between men and women have to do with PT items relevant to language abilities, where women tend to be more symmetrically distributed across the two factors. However, the frequency of right- and left-HP is similar in men and women and does not change for men when PT scores are recalculated after removal of unspecific items. Furthermore, once the items that assess verbal abilities were excluded, the corrected PT value for women showed higher right-HP. Our results provide some indications of a less pronounced lateralization of hemisphere-linked cognitive abilities in women. 相似文献
12.
Transplantation of immunodeficient mice with human hematopoietic cells has greatly facilitated studies of the earliest stages of human hematopoiesis. These include demonstration of the ability of injected 'human-specific' hematopoietic growth factors to enhance the production of human cells at multiple levels of differentiation. In contrast, the effects of continuous exposure to such molecules have not been well investigated. Here, we show that nonobese diabetic severe combined immunodeficiency mice genetically engineered to produce ng/ml serum levels of human interleukin-3 (IL-3), granulocyte/macrophage-stimulating factor (GM-CSF) and Steel factor (SF) display a complex phenotype when transplanted with primitive human bone marrow (BM) or fetal liver cells. This phenotype is characterized by an enhancement of terminal human myelopoiesis and a matched suppression of terminal human erythropoiesis, with a slight reduction in human B-lymphopoiesis in the BM of the engrafted mice. Human clonogenic progenitors are more prevalent in the blood of the transplanted growth factor-producing mice and this is accompanied by a very marked reduction of more primitive human cells in the BM. Our findings suggest that long-term exposure of primitive human hematopoietic cells to elevated levels of human IL-3, GM-CSF and SF in vivo may deleteriously affect the stem cell compartment, while expanding terminal myelopoiesis. 相似文献
13.
BACKGROUND AND PURPOSE: To appraise the potential benefit of a conformal technique with non-coplanar fields to minimise lung irradiation in the radiation treatment of breast. PATIENTS AND METHODS: A comparative study was carried out at planning level for six patients selected for their inadequate sparing of healthy lung tissue with the reference tangential technique. Plans were designed for the conventional tangential technique, for an alternative conformal approach with three beams and for the newly proposed technique with two non-coplanar beams. RESULTS: In average for the new technique compared to the reference, mean lung dose dropped from approximately 16 to 10.5 Gy, V(20 Gy) from 29.5 to 18.2% and the dose delivered to 1/3 (1/4) of the lung volume dropped from 28.5% (67.3%) to 8.7% (13.4%). For PTV, the volume receiving at least 90% of the prescribed dose resulted 97.4% for the new and 97.3% for the reference. Conformity index improved significantly from 2.58 for the reference to 1.84 for the new technique. CONCLUSIONS: For a subgroup population of breast cancer patients, where conventional techniques failed to achieve high conformal avoidance, a treatment modality with non-coplanar beams was developed and clinically tested for six patients. It resulted dosimetrically adequate, particularly when the risk of toxicity is relevant. 相似文献
14.
A Fogliata G Nicolini M Alber M Asell B Dobler M El-Haddad B H?rdemark U Jelen A Kania M Larsson F Lohr T Munger E Negri C Rodrigues L Cozzi 《Radiotherapy and oncology》2005,76(3):300-310
BACKGROUND AND PURPOSE: To evaluate the performance of ten different treatment-planning systems when intensity modulated (IMRT) plans are designed for breast treatments that include the irradiation of the internal mammary chain. PATIENTS AND METHODS: A dataset of five patients (CT images and volumes of interest) was distributed to design IMRT plans on the ten systems. To minimise biases, the same geometry and clinical planning aims were imposed on the individual plans. Results were analysed in terms of dose distributions and dose volume histograms. RESULTS AND CONCLUSIONS: For target coverage, the volume receiving more than 95% of the prescribed dose ranged from 77% (OTP) to 91% (Eclipse and Pinnacle), the volume receiving more than 107% ranged from 3.3% (Hyperion) to 23.2% (OTP). The mean dose to ipsilateral lung ranged from 13 Gy (Eclipse) to 18 Gy (OTP). The volume of the contralateral breast receiving more than 10 Gy ranged from 3% (Pinnacle) to 26% (Precise). The volume of heart receiving more than 20 Gy ranged from 7% (Eclipse) to 47% (Precise), the maximum significant dose to heart ranged from approximately 27 Gy (XiO) to approximately 49 Gy (Precise). The maximum significant dose to healthy tissue ranged from approximately 51 Gy (Eclipse) to approximately 62 Gy (OTP). It was also possible to show that the treatment geometry proposed here enables to minimise contralateral breast irradiation while keeping minimal ipsilateral lung (or heart) involvement and satisfactory target coverage. 相似文献
15.
Virgínia Carla de Oliveira Tatsuya Nagata Felipe C. Guimarães Fernanda A. Ferreira Elliot Watanabe Kitajima Cícero Nicolini Renato de Oliveira Resende Alice Kazuko Inoue-Nagata 《Virus genes》2013,46(1):190-194
A tymovirus was isolated in Brazil from tomato plants with severe symptoms of leaf mosaic and blistering. The virus was mechanically transmissible to solanaceous indicator host species. The infected plants contained icosahedral particles and chloroplasts with membrane deformations which are typical cytopathic effects caused by tymoviruses. Its coat protein amino acid sequence shares the maximum of 64 % identity with the tymovirus Chiltepin yellow mosaic virus, which suggested that it can be considered as a distinct member of the genus Tymovirus. In a phylogenetic tree, this tymovirus was clustered with other solanaceous-infecting tymoviruses. It was tentatively named as Tomato blistering mosaic virus (ToBMV). 相似文献
16.
17.
Home therapy with porcine factor VIIIC was safe and effective when administered to five hemophilic patients over periods of 8 1/2, 6, 4, 3 1/2, and 2 years. No significant transfusion reactions occurred. Before treatment with porcine factor VIIIC, all five had high-level, high- responding anti-human VIIIC inhibitors initially lacking anti-porcine factor VIIIC activity. Although specific anti-porcine VIIIC inhibitors arose in all patients, these were generally transient, and only one patient became refractory to treatment. We believe that porcine factor VIIIC is the treatment of choice in patients whose inhibitors do not cross-react. All five patients lost their original anti-human VIIIC inhibitors after starting treatment with porcine VIIIC, permitting the reintroduction of human VIIIC in three of them. There has been no recurrence of anti-human VIIIC inhibitor activity during 2 to 3 years of regular treatment with human VIIIC in these patients. This suggests that tolerance to human VIIIC has arisen as a result of treatment with porcine VIIIC. Porcine VIIIC may have a role in the desensitization of some factor VIIIC inhibitor patients. 相似文献
18.
Angeloni S Nicolini G Merli M Nicolao F Pinto G Aronne T Attili AF Riggio O 《The American journal of gastroenterology》2003,98(8):1844-1848
OBJECTIVES: Polymorphonuclear (PMN) cell count in ascitic fluid is the most useful test for the diagnosis of spontaneous bacterial peritonitis (SBP). We evaluated the validity of an automated blood cell counter for the PMN determination in ascitic fluid by comparing it with the traditional hematologic method with a light microscope in a manual counting chamber. METHODS: A total of 130 ascitic fluid samples were collected from 74 consecutive cirrhotics. The agreement between the two techniques was assessed according to Bland and Altman's method. The sensitivity, specificity, and positive and negative predictive values of the automated blood cell counter were calculated by considering the diagnosis of SBP as a PMN count > or = 250 cells/mm(3), determined by the manual method as the "gold standard." RESULTS: The mean PMN counts assessed by the manual method and the automated blood cell counter were 124 +/- 301 cells/mm(3) and 130 +/- 339 cells/mm(3), respectively (p = 0.89, ns). The mean +/- SD of the difference between manual and automated measurements was 6 +/- 61 cells/mm(3), whereas the limits of agreement were +127 cells/mm(3) (95% CI = +108 to +147) and -115 cells/mm(3) (95%CI = -96 to -135). SBP was diagnosed in 11 patients. All but one were correctly identified with the automated blood cell counter, with a sensitivity of 94% and a specificity of 100%; positive and negative predictive values were 100% and 99.1%, respectively. CONCLUSIONS: The manual method and the automated blood cell counter have a good agreement in the PMN determination in ascitic fluid, and the automated blood cell counter is a reliable tool for rapid diagnosis of SBP. 相似文献
19.
P. Tatarelli G. Fornaro V. Del Bono L.A. Nicolini A.M. Raiola F. Gualandi R. Varaldo T. Di Muccio M. Gramiccia L. Gradoni E. Angelucci C. Viscoli M. Mikulska 《Journal of infection and chemotherapy》2018,24(12):990-994
Visceral leishmaniasis has been recognized as an opportunistic infection affecting people with cellular-immunity impairment, including hematopoietic cell transplantation (HCT) recipients. We describe the case of a young Italian man with Hodgkin lymphoma, who developed visceral leishmaniasis after multiple lines of chemotherapy and allogenic HCT. Literature review of visceral leishmaniasis in HCT recipients was also performed. Eleven patients (median age 50 years, 9 male) developed visceral leishmaniasis after allogenic (n = 9) and autologous (n = 2) HCT. Most of them presented with fever and pancytopenia. Bone marrow examination was the main diagnostic technique; liposomal amphotericin B was the treatment of choice. Four out of eight patients (for whom data are available) experienced visceral leishmaniasis relapse. Visceral leishmaniasis in HCT recipients is a rare event that should be suspected in patients with persistent fever, pancytopenia and possible exposure to Leishmania spp., remembering that – as well as South-East Asia, East Africa and South America - it is endemic in several European regions. 相似文献
20.
Two alpha-globin structural mutants were mapped to their encoding loci by in vitro translation of hybrid-selected alpha 1- and alpha 2-globin mRNA. The more highly expressed mutant, alpha Spanish Town (alpha 27Val), is encoded at the alpha 2 locus and the less expressed mutant, alpha Fort de France (alpha 45Arg), is encoded at the alpha 1 locus. These results further define the distribution of alpha-globin structural mutations within the alpha-globin gene cluster and substantiate the dominant role of the alpha 2-globin locus in alpha- globin expression. 相似文献