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排序方式: 共有755条查询结果,搜索用时 31 毫秒
101.
102.
Priya Gogoi Saedeh Sepehri Yi Zhou Michael A. Gorin Carmela Paolillo Ettore Capoluongo Kyle Gleason Austin Payne Brian Boniface Massimo Cristofanilli Todd M. Morgan Paolo Fortina Kenneth J. Pienta Kalyan Handique Yixin Wang 《PloS one》2016,11(1)
Current analysis of circulating tumor cells (CTCs) is hindered by sub-optimal sensitivity and specificity of devices or assays as well as lack of capability of characterization of CTCs with clinical biomarkers. Here, we validate a novel technology to enrich and characterize CTCs from blood samples of patients with metastatic breast, prostate and colorectal cancers using a microfluidic chip which is processed by using an automated staining and scanning system from sample preparation to image processing. The Celsee system allowed for the detection of CTCs with apparent high sensitivity and specificity (94% sensitivity and 100% specificity). Moreover, the system facilitated rapid capture of CTCs from blood samples and also allowed for downstream characterization of the captured cells by immunohistochemistry, DNA and mRNA fluorescence in-situ hybridization (FISH). In a subset of patients with prostate cancer we compared the technology with a FDA-approved CTC device, CellSearch and found a higher degree of sensitivity with the Celsee instrument. In conclusion, the integrated Celsee system represents a promising CTC technology for enumeration and molecular characterization. 相似文献
103.
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105.
Luca Luiselli Thomas Madsen Dario Capizzi Lorenzo Rugiero Nic Pacini Massimo Capula 《Ecological Research》2011,26(4):745-753
A review of several long-term studies has recently suggested that snakes might be declining in large parts of the world. Additional
data from other long-term studies are therefore urgently needed in order to assess the generalities of such suggested declines.
Based on a 20-year study, we analyzed demographic data on adult dice snakes (Natrix tessellata) studied in central Italy between 1985 and 2004. Both male and female dice snakes were relatively long-lived, with no significant
differences in longevity between the sexes. Individual males and females were observed over a maximum of 10 and 14 years,
respectively. However, the among-year recapture rates between the year the snakes were initially captured and the subsequent
year (i.e., year 1 to year 2) was significantly lower (45%) than the among-year recapture rates during subsequent years (74%;
i.e., year 2 to year 3), suggesting that a large proportion of the snakes at first capture were in fact not resident within
our study area, and hence many snakes were migrating in and out of our 2-km stream study site, with no inter-sexual difference
in dispersal rates. Sex ratio was virtually equal if we consider the study period as a whole. Significant annual fluctuations
were, however, observed through the study. In 1985–1990, 1993–1995, 1998 and 1999 the sex ratio was male-biased, whereas in
2000–2004 female-biased. In terms of both survival and recapture probabilities, model selection showed that Akaike’s information
criterion favored the model incorporating body size, with the model incorporating year having an intermediate likelihood,
and the model with sex included being the most disfavored. Total population number estimates suggest an average 86 adult individuals
along the 2 km of stream with only minor annual variations. However, a significant decrease in the number of males occurred
during the last 6 years of our study. Thus, further monitoring of this population is warranted in light of the decline of
snake populations reported recently. 相似文献
106.
107.
Vanna Fierabracci Pellegrino Masiello Michela Novelli Ettore Bergamini 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1991,570(2):285-291
An amino acid analysis by reversed-phase high-performance liquid chromatography after precolumn derivatization with phenyl isothiocyanate was adapted to the determination of free amino acids in plasma or other biological fluids and in tissue homogenates. Preparation of samples included deproteinization by 3% sulphosalicylic acid, and careful removal under high vacuum of residual phenyl isothiocyanate after derivatization. A Waters Pico-Tag column (15 cm long) was used, immersed in a water-bath at 38°C. In rat or human plasma, separation of 23 individual amino acids, plus the unresolved pair tryptophan and ornithine, was obtained within 13 min. Including the time for column washing and re-equilibration, samples could be chromatographed at 23-min intervals. Variability was tested for each amino acid by calculating the coefficients of variation of retention times (less than 1% in the average) and peak areas (less than 4% for both intra-day and inter-day determinations). The linearity for each standard amino acid was remarkable over the concentration range 3–50 nmol/ml. The mean recovery of amino acid standards added to plasma prior to derivatization was 97 ± 0.8%, except for aspartate (82%) and glutamate (81%). This method is rapid (almost three samples per hour can be analysed, more than in any other reported technique), with satisfactory precision, sensitivity and reproducibility. Therefore, it is well suited for routine analysis of free amino acids in both clinical and research work. 相似文献
108.
A. M. Ferraris Rosa Mangerini Gian Franco Gaetani Cristina Romei Aldo Pinchera Furio Pacini 《Human genetics》1997,99(2):202-205
Multiple endocrine neoplasia type 2 (MEN 2) is a dominantly inherited cancer syndrome characterized by medullary thyroid
carcinoma (MTC) and other tumors. Since MTC can also occur in a sporadic form and as familial medullary thyroid carcinoma,
this neoplasm offers a unique opportunity to investigate the difference of origin, if any, between the sporadic and the hereditary
forms of a tumor. While sporadic malignancies have usually been found to result from a mutational event occurring at the single-cell
level and are therefore monoclonal, studies on hereditary neoplasms have been scarce and often produced conflicting results.
In order to determine the clonal origin of sporadic MTCs and of those occurring in MEN 2 syndromes we used a clonality assay
based on a polymorphic trinucleotide repeat of the X-linked human androgen-receptor gene. We found that 10 out of 11 MTCs
expressed a polyclonal pattern of X inactivation, including a significant percentage of the cases clinically defined as sporadic.
Received: 21 May 1996 / Revised: 14 August 1996 相似文献
109.
Benedetti Ettore Iacovino Rosa Pedone Carlo Rossi Filomena Saviano Michele Isernia Carla Montesarchio Daniela de Napoli Lorenzo Piccialli Gennaro 《International journal of peptide research and therapeutics》1997,4(3):129-134
Summary An N- and C-protected derivative ofhomo-β-leucine, Fmoc-homo-β-(S)-leucine methyl ester, synthesized from the corresponding proteinogenic parent α-amino acid in enantiopure form has been
fully characterized in the solid state by X-ray diffraction analysis. The crystal conformation of this new residue indicates
and extended conformation for thishomo-β-residue, with the ϕ torsion angle being more constrained than the μ and ψ angles. 相似文献
110.