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91.
92.
Analysis of the floral transcriptome uncovers new regulators of organ determination and gene families related to flower organ differentiation in Gerbera hybrida (Asteraceae) 下载免费PDF全文
Laitinen RA Immanen J Auvinen P Rudd S Alatalo E Paulin L Ainasoja M Kotilainen M Koskela S Teeri TH Elomaa P 《Genome research》2005,15(4):475-486
Development of composite inflorescences in the plant family Asteraceae has features that cannot be studied in the traditional model plants for flower development. In Gerbera hybrida, inflorescences are composed of morphologically different types of flowers tightly packed into a flower head (capitulum). Individual floral organs such as pappus bristles (sepals) are developmentally specialized, stamens are aborted in marginal flowers, petals and anthers are fused structures, and ovaries are located inferior to other floral organs. These specific features have made gerbera a rewarding target of comparative studies. Here we report the analysis of a gerbera EST database containing 16,994 cDNA sequences. Comparison of the sequences with all plant peptide sequences revealed 1656 unique sequences for gerbera not identified elsewhere within the plant kingdom. Based on the EST database, we constructed a cDNA microarray containing 9000 probes and have utilized it in identification of flower-specific genes and abundantly expressed marker genes for flower scape, pappus, stamen, and petal development. Our analysis revealed several regulatory genes with putative functions in flower-organ development. We were also able to associate a number of abundantly and specifically expressed genes with flower-organ differentiation. Gerbera is an outcrossing species, for which genetic approaches to gene discovery are not readily amenable. However, reverse genetics with the help of gene transfer has been very informative. We demonstrate here the usability of the gerbera microarray as a reliable new tool for identifying novel genes related to specific biological questions and for large-scale gene expression analysis. 相似文献
93.
Prognostic factors in laryngeal carcinoma: the role of apoptosis,p53, proliferation (Ki-67) and angiogenesis 总被引:3,自引:0,他引:3
Teppo H Soini Y Melkko J Koivunen P Alho OP 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2003,111(4):451-457
Even though the roles of different known or suggested prognostic factors in laryngeal cancer have been studied in detail, clinical stage at time of diagnosis and anatomic subsite of the tumour remain the only practical predictors of clinical outcome and offer the only guidelines in the planning of treatment. In this study, the relative roles of known demographic and clinical prognostic factors, in addition to four histopathological factors, were evaluated in a sample of 100 laryngeal carcinoma patients with multivariate analysis using the Cox regression model. In addition to advanced stage (stage III-IV) (relative hazard of death (HR) 8.9, p=0.01) and supraglottic disease (HR 5.6, p=0.02), high apoptotic index (HR 11.1, p=0.05) was significantly associated with poor survival. Cell proliferation, p53 and angiogenesis did not significantly affect the prognosis. In the future, high degree of apoptosis could be used to identify patients with poor prognosis in laryngeal cancer. 相似文献
94.
Haider Al‐Hello Petri Ylipaasto Teemu Smura Elisabeth Rieder Tapani Hovi Merja Roivainen 《Journal of medical virology》2009,81(2):296-304
It was shown recently that 15 successive passages of a laboratory strain of the Coxsackie B virus 5 in a mouse pancreas (CBV‐5‐MPP) resulted in apparent changes in the virus phenotype, which led to the capacity to induce a diabetes‐like syndrome in mice. For further characterization of islet cell interactions with a passaged virus strain, a murine insulinoma cell line, MIN‐6, was selected as an experimental model. The CBV‐5‐MPP virus strain was not able to replicate in MIN‐6 cells in vitro but required adaptation over a few days for progeny production and the generation of cytopathic effects. In order to determine the genetic characteristics required for virus growth in MIN‐6 cells, the whole genome of the MIN‐6‐adapted virus variant was sequenced, and critical amino acids were identified by comparing the sequence with that of a virus strain passaged repeatedly in the mouse pancreas. The results of site‐directed mutagenesis demonstrated that only one residue, amino acid 94 of VP1, is a major determinant for virus adaptation to MIN‐6 cells. J. Med. Virol. 81:296–304, 2009. © 2008 Wiley‐Liss, Inc. 相似文献
95.
96.
Tuula Vasankari Pekka Holmström Jukka Ollgren Kari Liippo Maarit Kokki Petri Ruutu 《BMC public health》2007,7(1):291
Background
We investigated the patient- and treatment-system dependent factors affecting treatment outcome in a two-year cohort of all treated culture-verified pulmonary tuberculosis (TB) cases to establish a basis for improving outcomes. 相似文献97.
Value of duplex Doppler ultrasonography in renal colic 总被引:1,自引:0,他引:1
OBJECTIVES: The aim of our study was to determine the value of duplex Doppler ultrasonography (DDU) in the patients' evolution with renal colic. The study of the resistive index (RI), difference of the RI (ARI) associated with a DDU intravesical recording (ureteral jets) were compared with renographic findings in renal colic. PATIENTS AND METHODS: Between October 1998 and January 2001 we studied 377 cases with suspected renal colic by intravenous pyelography (IVP), grey-scale ultrasonography and DDU with determination of the RI, the difference between the RI of ipsilateral and contralateral kidneys (ARI) and the amplitude (maximum length of the intravesical ureteral jet), velocity and frequency of the urine bolus. We considered normal values RI < or = 0.70 and ARI < or = 0.06. VP was used as a referee investigation and the ureteral intravesical jets were determined in standard conditions. All patients came to the hospital between 4 and 12 h after the onset of the renal colic. RESULTS: We found four series of patients: 1, acute (complete) obstructed kidney (IVP nonfunctional) and dilatation at normal grey-scale, with normal contralateral kidney (n = 153). In this series we found RI > 0.70 in 87%, RI > 0.06 in 90% and absent ureteral intravesical jet of the obstructed kidney site in 89%; 2, acute (complete) obstructed kidney (IVP nonfunctional) without abnormalities at normal grey-scale, with normal contralateral kidney (n = 57). In this series we found RI > or = 0.70 in 73.5%, deltaRI > 0.06 in 82.5% of patients, absent or asymmetric ureteral intravesical jet in 80.7% of cases; 3, incomplete obstructed kidney (IVP with various degree of ureterohydronephrosis) with normal contralateral kidney (n = 96). In this series we found RI > or = 0.70 in 58.3% and deltaRI > 0.06 in 64.5% of patients, asymmetric ureteral intravesical jets in 74% of cases; 4, normal both kidneys normal IVP) were found in 71 cases (18.8%). In this series we found RI < 0.70 in 80.2%, deltaRI < or = 0.06 in 89% of cases, normal ureteral intravesical jets in 93% of cases. The mean RI was 0.76 (0.05) in 306 obstructed kidneys, significantly higher than the mean RI of 0.62 (0.05) in 448 normal kidneys (P < 0.001). The ARI in patients with obstruction was significantly higher than in patients with normal both kidneys, at 0.08 (0.05) and -0.001 (0.03), respectively (P < 0.001). The RI was sensitive in 75.5% and specific in 92.5% and ARI was sensitive in 80.7% and specific in 95.7% (versus IVP, considered the referee value). The presence of the intravesical ureteral jets of the renal colic side, associated with the values of RI (RI < or = 0.70) and deltaRI (deltaRI < or = 0.06), was followed by spontaneous passage of the stones in 71% of cases. CONCLUSIONS: Renal DDU and consecutively, intravesical evaluation of ureteral jets could detect acute renal obstruction and, as a functional investigation, could have a predictive value regarding the ureteral stones passage. It could replace the IVP, being a sensitive and highly specific test. 相似文献
98.
Effects of bisphenol A and artificial UVB radiation on the early development of Rana temporaria 总被引:3,自引:0,他引:3
Ultraviolet-B (UVB) radiation is one environmental factor that may act in concert with other stressors, such as xenobiotics, to produce adverse effect on amphibian populations. Embryos (< 24 h old) of the common frog (Rana temporaria) were exposed to four concentrations (0, 10, 100, or 1000 microg/L) of bisphenol A (BPA), with and without ultraviolet-B (UVB) radiation, for 20 d in the laboratory. Throughout the experiment the biologically effective daily UVB dose, calculated with Setlow's DNA action spectrum, was 2.80 kJ m(-2). UVB radiation as such did not have any significant effect on frog embryos. However, a BPA treatment of 1000 microg/L had a significant effect on embryos in both the UVB and no-UVB treatments, with the effect being greater with UVB. UVB produced a significant decrease in survival in the newly hatched frog larvae at all BPA concentrations. These results demonstrate that simultaneous exposure to these two stress factors is more harmful to R. temporaria larvae than exposure to one stressor alone. 相似文献
99.
100.
Sorodoc L Păduraru D Frasin M Benchea B Petriş O Zaharia I 《Revista medico-chirurgical?? a Societ????ii de Medici ??i Naturali??ti din Ia??i》2002,106(1):70-75
Core body temperature below 35 degrees C is defining arbitrarily hypothermia. There is no worldwide consensus concerning the staging and resuscitation strategies in such a vital emergency, not even in rewarming strategy. Accidental hypothermia has its own "survival chain", modifying some steps or the timing in the common cardiopulmonary resuscitation protocol, according to some particularities of the metabolism in such an accident. Taking into account the two major events during hypothermic conditions (ventricular fibrillation and coma), we have proposed a better borderline between the three severity classes, based on clinical, paraclinical and prognostic arguments. The interest in this special environmental emergency situation is coming not only from its incidence, but especially from its particular long time period in which the resuscitation maneuvers could be effective, so that a literature review mixed with our practical observations may be of didactical and legal benefit also. 相似文献