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991.
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993.
Jakub Pazdrowski Pieńkowski Piotr Magdalena Kordylewska Anna Wegner Paweł Golusiński Wojciech Golusiński 《Reports of Practical Oncology and Radiotherapy》2010,15(3):60-63
Background
The exact assessment of a tonsil carcinoma''s size is often difficult because of the tumour''s submucosal extension and deep infiltration.Aim
The aim of the study is to assess the usefulness of intraoperative ultrasonography in tonsil cancer.Material
Twenty patients with carcinoma of the tonsil were included in the study (squamous cell carcinoma keratosis – 12, squamous cell carcinoma akeratosis – 6, diffuse large B cell lymphoma – 1, neoplasma malignum microcellulare – 1).Method
Transcutaneous, endoscopic, and intraoperative ultrasonography were performed using a linear 7.5 MHz probe.Results
The difference in the results was statistically significant between palpation examination and intraoperative ultrasonographic examination, between transcutaneous ultrasonographic examination and intraoperative ultrasonographic examination, and between endoscopic ultrasonographic examination and intraoperative ultrasonographic examination in tonsil tumours. Generally, tumour size assessed by intraoperative ultrasonography was more advanced than those assessed by other methods.Conclusions
Intraoperative ultrasonography is a safe, non-invasive method, which can be repeated at every stage of surgery. There were no contraindications or side effects. In all cases histological margins corresponded to sonographic margins. Intraoperative ultrasonography provides a quick and reliable orientation during resection of tonsil carcinoma. 相似文献994.
Ida Bærholm Schnell Magdalena Fraser Eske Willerslev M. Thomas P. Gilbert 《Arthropod-Plant Interactions》2010,4(2):107-116
A DNA-based tool was validated that potentially enables the characterisation of both plant and insect of origin of small (approximately
1 ml) samples of bee honey. Using this method, mitochondrial, nuclear and chloroplast DNA (mtDNA, nuDNA, cpDNA) markers were
successfully extracted, PCR amplified, and sequenced from a range of honeys, and the relative amount of plant nuDNA and cpDNA,
and bee mtDNA in the samples was quantified using quantitative real-time PCR. Short, but taxonomically informative lengths
of insect and plant organelle DNA could be routinely recovered from all honey samples tested, and longer organelle, and nuclear
DNA sequences can be recovered from many. The data also enabled preliminary characterisation of the quality of these different
DNA sources in honey. Although the absolute quantity of the different genetic markers varied considerably between sample,
a general trend was observed of insect mtDNA dominating over plant organelle DNA, and with plant nuclear DNA at the lowest
levels. Furthermore there was a clear correlation between the plant DNA content and the success of the PCR assays. To maximise
successful characterisation of samples, future studies are recommended to focus on the use of organelle markers, and limit
the size of PCR amplicons targeted, although with appropriate sample selection and assay optimisation, other approaches may
be possible. 相似文献
995.
Martyńska L Polkowska J Wolińska-Witort E Chmielowska M Wasilewska-Dziubińska E Bik W Baranowska B 《Reproductive biology》2006,6(Z2):29-35
Orexin A (OxA), a recently discovered neuropeptide, is synthesized mainly by neurons located in the posterolateral hypothalamus and is a 33 amino acid peptide with N-terminal pyroglutamyl residue and two inter-chain disulfide bonds. It is a potent agonist for both the orexin-1 (OxR1) and orexin-2 (OxR2) receptors. Orexin A and its receptors are widely distributed in the central nervous system (CNS) and peripheral organs suggesting the pleiotropic functions of this peptide. Orexin A is involved in food intake and energy expenditure in many species, but also plays an important role in the regulation of the hypothalamo-pituitary axes. The role of orexin A in the regulation of the hypothalamo-pituitary-adrenal, -thyroid, -somatotropic, and -gonadal axes has been inadequately investigated. Orexinergic fibres project to the septal-preoptic and arcuate nucleus-median eminence regions--two areas of the brain directly involved in the synthesis and release of gonadotropin-releasing hormone (GnRH). Contentious opinions concerning the influence of orexin A over the hypothalamo-gonadotropic axis have been reported in both in vivo and in vitro studies. Further studies are necessary to clarify relationships between orexin A and the hypothalamo-pituitary hormones involved in reproduction. 相似文献
996.
Standardized reagents and protocols for engineering zinc finger nucleases by modular assembly 总被引:1,自引:0,他引:1
Wright DA Thibodeau-Beganny S Sander JD Winfrey RJ Hirsh AS Eichtinger M Fu F Porteus MH Dobbs D Voytas DF Joung JK 《Nature protocols》2006,1(3):1637-1652
Engineered zinc finger nucleases can stimulate gene targeting at specific genomic loci in insect, plant and human cells. Although several platforms for constructing artificial zinc finger arrays using "modular assembly" have been described, standardized reagents and protocols that permit rapid, cross-platform "mixing-and-matching" of the various zinc finger modules are not available. Here we describe a comprehensive, publicly available archive of plasmids encoding more than 140 well-characterized zinc finger modules together with complementary web-based software (termed ZiFiT) for identifying potential zinc finger target sites in a gene of interest. Our reagents have been standardized on a single platform, enabling facile mixing-and-matching of modules and transfer of assembled arrays to expression vectors without the need for specialized knowledge of zinc finger sequences or complicated oligonucleotide design. We also describe a bacterial cell-based reporter assay for rapidly screening the DNA-binding activities of assembled multi-finger arrays. This protocol can be completed in approximately 24-26 d. 相似文献
997.
Lukasz Wicherek Magdalena Dutsch-Wicherek Krystyna Galazka Tomasz Banas Tadeusz Popiela Agata Lazar Beata Kleinrok-Podsiadlo 《Reproductive biology and endocrinology : RB&E》2006,4(1):41-9
Background
The coexistence of endometrial and immune cells during decidualization is preserved by the ability of endometrial cells to regulate the cytotoxic immune activity and their capability to be resistant to immune-mediated apoptosis. These phenomena enable the survival of endometrial ectopic cells. RCAS1 is responsible for regulation of cytotoxic activity. Metallothionein expression seems to protect endometrial cells against apoptosis. The aim of the present study was to evaluate RCAS1 and metallothionein expression in human ovarian and scar endometriomas in relation to the presence of immune cells and their activity. 相似文献998.
The antioxidant and prooxidant effects of tannic, ellagic and gallic acids (1-60 microM) in the presence of hydrogen peroxide (40 and 100 microM) or copper ions (50 microM) on B14 Chinese hamster cells were examined. The fluorescence probe DCFH-DA (dichlorofluorescein-diacetate) was used to analyse the levels of reactive oxygen species. This method showed the reduction in oxidation of DCF (dichlorofluorescein). It indicates that antioxidant capacity of tested polyhenols is decreased in the presence of hydrogen peroxide or copper ions. Spectrophotometric assay with Ellman's reagent was used to determine SH-groups. The experimental results revealed the oxidative modification of proteins after exposure to polyphenols at concentrations above 15 microM. Additional incubation with H2O2 or Cu(2+) ions showed the prooxidant activity of tested complexes also for polyphenols used at a concentration of 1 microM. Fluorescence method with Hoechst 33258/propidium iodide dyes was used to study apoptotic and necrotic cell death. The obtained data demonstrated that polyphenols alone, as well as in the presence of hydrogen peroxide or copper ions, can induce DNA fragmentation. 相似文献
999.
1000.
Phenotypic approaches based on metabolic and biological characteristics of Corynebacterium pseudotuberculosis have been limited due to insufficient discrimination between closely related isolates. In this paper we present performance and convenience of three molecular typing methods: BOX-PCR, random amplification of polymorphic DNA (RAPD) and amplification of DNA fragments surrounding rare restriction site (ADSRRS-fingerprinting) in genome analysis of these bacteria. Among examined 61 strains there were distinguished four, eight and 10 different genotypes by BOX-PCR, RAPD and ADSRRS-fingerprinting, respectively. The value of discrimination index was the lowest for BOX-PCR (D = 0.265), much bigger for RAPD (D = 0.539) and the highest for ADSRRS-fingerprinting (D = 0.604). The good discriminatory ability and reproducibility of RAPD and ADSRRS-fingerprinting indicates that those techniques may be particularly applied for epidemiological studies of C. pseudotuberculosis isolates. We found that ADSRRS-fingerprinting is a rapid method offering good discrimination power, excellent reproducibility and may be applied for epidemiological studies of intraspecific genetic relatedness of C. pseudotuberculosis strains. 相似文献