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排序方式: 共有429条查询结果,搜索用时 218 毫秒
271.
272.
Giuseppe Aprile Giovanna De Maglio Jessica Menis Mariaelena Casagrande Francesco Tuniz Federica Edith Pisa Caterina Fontanella Miran Skrap Carlo Alberto Beltrami Gianpiero Fasola Stefano Pizzolitto 《International journal of molecular sciences》2013,14(2):2370-2387
Brain metastases (BM) from colorectal cancer (CRC) are a rare but increasing event. Surgical resection of oligometastatic disease, including BM, may produce a survival benefit in selected patients. Previous studies described the HER-2 expression patterns in CRC patients, but its prognostic role still remains controversial. Information on the HER-2 expression in BM from CRC is currently lacking. Among the over 500 patients treated at our Department of Neurosurgery in the last 13 years (1999–2012), we identified a cohort of 50 consecutive CRC patients resected for BM. Clinical data were retrospectively reviewed using electronic hospital charts and surgical notes. Formalin-fixed, paraffin-embedded tissue samples were retrieved and histologically reviewed. HER-2 status was assessed on 4-μm sections by HerceptTest™, and scored by two pathologists according to gastric cancer HER-2 status guidelines. In score 2+ cases HER-2 gene copy number was analyzed by FISH, performed using the PathVysion HER-2 DNA Probe Kit. Median age at time of BM resection was 65 years (35–82); most patients were males (60%) with a good performance status. The majority of the BM were single (74%) and sited in the supratentorial area (64%); 2–4 lesions were diagnosed in 9 patients (18%), and >4 in 3 patients (6%). The rate of HER-2 positivity (defined as IHC score 3+ or IHC score 2+ and FISH gene amplification) was 8.1% for the primary CRC tumors and 12% for their corresponding BM. The concordance rate between primary tumors and matched BM was 89%. Median overall survival after neurosurgery was 6.5 months for HER-2 IHC score 0 vs. 4.6 months for HER-2 IHC score 1+/2+/3+; the difference was statistically significant (p = 0.01, Log-rank test). HER-2 positivity of our case cohort was low but comparable to literature. Concordance rate of HER-2 expression between BM and corresponding primary tumors is high and similar to those reported for breast and gastric cancers. Our data suggest a potential negative prognostic value of HER-2 expression in brain lesions from CRC. 相似文献
273.
Maria Giovanna Buonomenna Giovanni Golemme Caterina Maria Tone Maria Penelope De Santo Federica Ciuchi Enrico Perrotta 《Advanced functional materials》2012,22(8):1759-1767
The preparation and characterization of new, tailor‐made polymeric membranes using poly(styrene‐b‐butadiene‐b‐styrene) (SBS) triblock copolymers for gas separation are reported. Structural differences in the copolymer membranes, obtained by manipulation of the self‐assembly of the block copolymers in solution, are characterized using atomic force microscopy, transmission electron microscopy, and the transport properties of three gases (CO2, N2, and CH4). The CH4/N2 ideal selectivity of 7.2, the highest value ever reported for block copolymers, with CH4 permeability of 41 Barrer, is obtained with a membrane containing the higher amount of polybutadiene (79 wt%) and characterized by a hexagonal array of columnar polystyrene cylinders normal to the membrane surface. Membranes with such a high separation factor are able to ease the exploitation of natural gas with high N2 content. The CO2/N2 ideal selectivity of 50, coupled with a CO2 permeability of 289 Barrer, makes SBS a good candidate for the preparation of membranes for the post‐combustion capture of carbon dioxide. 相似文献
274.
Caterina Levantesi Rosanna La Mantia Uta Böckelmann M. Neus Ayuso-Gabella Valter Tandoi Thomas Wintgens 《The Science of the total environment》2010,408(21):4923-4930
Managed Aquifer Recharge (MAR) is becoming an attractive option for water storage in water reuse processes as it provides an additional treatment barrier to improve recharged water quality and buffers seasonal variations of water supply and demand. To achieve a better understanding about the level of pathogenic microorganisms and their relation with microbial indicators in these systems, five waterborne pathogens and four microbial indicators were monitored over one year in three European MAR sites operated with reclaimed wastewater. Giardia and Cryptosporidium (oo)cysts were found in 63.2 and 36.7% of the samples respectively. Salmonella spp. and helminth eggs were more rarely detected (16.3% and 12.5% of the samples respectively) and Campylobacter cells were only found in 2% of samples. At the Belgian site advanced tertiary treatment technology prior to soil aquifer treatment (SAT) produced effluent of drinking water quality, with no presence of the analysed pathogens. At the Spanish and Italian sites amelioration of microbiological water quality was observed between the MAR injectant and the recovered water. In particular Giardia levels decreased from 0.24-6.14 cysts/L to 0-0.01 cysts/L and from 0.4-6.2 cysts/L to 0-0.07 cysts/L in the Spanish and Italian sites respectively. Salmonella gene copies and Giardia cysts were however found in the water for final use and/or the recovered groundwater water at the two sites. Significant positive Spearman correlations (p < 0.05, rs range: 0.45-0.95) were obtained, in all the three sites, between Giardia cysts and the most resistant microbial markers, Clostridium spores and bacteriophages. 相似文献
275.
276.
For many years it has been known that PARAFAC offers a very attractive approach for modeling fluorescence excitation-emission matrices. Due to the uniqueness of the PARAFAC model and analogy between the structure of fluorescence data and the PARAFAC model, it is apparent that PARAFAC can resolve overlapping signals into pure spectra and relative concentrations under mild conditions. There are hundreds of applications exemplifying this, but still the use of PARAFAC has not spread from chemometrics to more main-stream analytical chemistry. Many reasons can be offered to explain this, but one seems to be that in practice it is difficult for chemometric novices to make use of PARAFAC. Selection of wavelengths, handling of scatter and of outliers are all issues that must be dealt with in order to build a good PARAFAC model. In this paper, a new algorithm called EEMizer is developed that aims to automate the use of PARAFAC. Through several examples it is shown how this algorithm can provide appealing PARAFAC models of data that would otherwise be hard to model. 相似文献
277.
Wojciech Jó?wicki Anna A. Bro?yna Jerzy Siekiera Andrzej T. Slominski 《International journal of molecular sciences》2016,17(3)
In the present study, we evaluated tumor-infiltrating lymphocytes (TILs) and blood regulatory T lymphocyte (Tregs, CD4+/CD25+/FoxP3+) expression in bladder cancer patients. The number of CD4+, CD8+, CD25+, FoxP3+ and CD20+ TILs was analyzed in association with clinico-pathomorphological features. In more advanced metastasizing tumors, showing non-classic differentiation (ND) and a more aggressive tissue invasion type (TIT), the number of TILs decreased. A low number of CD4+ TILs was associated with poor prognosis. Similarly, Treg frequency before surgery and after surgical treatment was significantly lower in more advanced tumors. The changes in TILs, as well as of local and systemic Tregs, were accompanied by changes in the histological phenotype of urothelial carcinoma regarding pT stage, NDs, TIT, and clinical outcomes. The number of TILs and the frequency of blood Tregs (indicators of antitumor response) may be essential for choosing an immunotherapy that is adjusted to the immune status according to the phase of tumor growth. Moreover, a significant reduction in the number of CD4+ and CD8+ TILs with the development of NDs in more advanced tumors may be associated with lower tumor immunogenicity, resulting in immune tolerance towards tumor tissue. These observations and the tendency of urothelial bladder carcinoma to undergo NDs in a heterogeneous manner during tumor progression suggest complex interactions between bladder cancer immunogenicity and stages of tumor progression. 相似文献
278.
Artoni Silvia Bastiani Luca Buzzi Maria Claudia Buzzi Marina Curzio Olivia Pelagatti Susanna Senette Caterina 《Universal Access in the Information Society》2018,17(1):191-210
Universal Access in the Information Society - This study investigates whether ICT technology can enhance applied behavior analysis (ABA) rehabilitation therapy for children with autism. A... 相似文献
279.
Lucia Mason Sonia Zaccoletti Sara Scrimin Maria Caterina Tornatora Elena Florit Thomas Goetz 《Journal of Computer Assisted Learning》2020,36(1):89-101
This study investigated the contribution of both physiological and behavioural process data to the comprehension of conflicting digital texts. We measured skin conductance level (SCL) as an index of arousal and the first-pass and look-back fixation times as indices of visual behaviour while reading. Forty-eight seventh graders read four webpages on genetically modified food, and their comprehension of the texts was measured using a short essay. Results showed that the type of webpage did not differentiate the process data. Statistical procedures for the comparison of a series of regression models revealed that SCL and first-pass fixation time negatively predicted multiple-text comprehension while also considering the control variables. The more the students were aroused while reading and the longer the processing time during the first encounter with the reading material, the poorer their comprehension of the conflicting texts. However, the interaction of prior knowledge and arousal positively predicted multiple-text comprehension. A slope analysis revealed that when participants had high prior knowledge and high arousal during reading, their postreading comprehension performance increased. 相似文献
280.
Riccardo Poli Mathew Salvaris Caterina Cinel 《Genetic Programming and Evolvable Machines》2012,13(3):377-405
We propose the use of genetic programming (GP) as a means to evolve brain–computer interfaces for mouse control. Our objective is to synthesise complete systems, which analyse electrical brain signals and directly transform them into pointer movements, almost from scratch, the only input provided by us in the process being the set of visual stimuli to be used to generate recognisable brain activity. Experimental results with our GP approach are very promising and compare favourably with those produced by support vector machines. 相似文献