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121.
Summary We have examined a water-dominated multicomponent system after irradiation in the multimegarad dose range with gamma rays from a60Co source at both 77 and 310 K. The constituents were simple organic compounds in the proportions in which they appear in a dense interstellar cloud: HCN/CH3OH/CH3CN/C2H5CN/HCOOH=10.60.20.10.05. The total amounts were adjusted to correspond to a carbon to nitrogen ratio of 1.8 and a water content of about 50% in a cometary nucleus where the dust to volatiles ratio is 1; the total amount of CN-bearing compounds was taken to correspond to 0.4% of the cometary mass. In experiments at 310 K about 40 radiolytic products are identified, among them aldehydes and amino and carboxylic acids. Abundant polymeric material (Mw up to 80,000 daltons) is formed. The basic aspects of radiolysis of the liquid system are present also at 77 K, although at radiation-chemical yields that are lower by one to two orders of magnitude. We have considered the relevance of the present findings to the chemistry of a liquid-water core and the icy layers of a cometary nucleus.  相似文献   
122.
In contrast to cold and eurythermal waters, benthic communities of warm brooks in temperate regions have been inadequately studied. In order to investigate the effects of water thermal regime on the benthic communities of warm waters and their relationships with those of cold and eurythermic ones, the macrozoobenthos was studied at eight sites in the Toplica River, and at four sites in its tributary, the Termalni brook. Investigations were carried out seasonally from April 2000 to January 2001. Warm waters of the Termalni brook were characterized by specific macrozoobenthos assemblages that exhibited significant differences to the populations of eurythermal and cold waters of the Toplica River. The dominant taxa in the macrozoobenthos community of warm waters were mainly Gastropoda species. Moreover, benthic communities of warm waters were characterized by lower diversity and greater biomass in comparison with those of cold and eurythermal waters. The gradient of average annual temperatures represented the main ecological factor influencing changes of diversity and biomass along the course of the investigated Termalni brook. Inflow of warm waters at site T6 lead to a decrease in macrozoobenthos abundance and changes in qualitative and quantitative composition of the benthocoenosis of a highland stream, but did not significantly alter diversity.  相似文献   
123.
A total of 835 patients with symptoms of chronic prostatitis syndrome and no evidence of structural or functional lower genitourinary tract abnormalities were examined in a three year period at the Outpatient Department for Urogenital Infections, University Hospital for Infectious Diseases "Dr. Fran Mihaljevi?" Zagreb, Croatia. Disease etiology was determined in 482 (57.72%) patients. Chlamydia trachomatis was proved to be the causative pathogen in 161 patients, Trichomonas vaginalis in 85, Escherichia coli in 68, Enterococcus in 51, Proteus mirabilis in 20, Klebsiella pneumoniae in 9, Streptococcus agalactiae in 15, Ureaplasma urealyticum in 49 patients with chronic prostatitis. Other patients had mixed infection. In 257 (53.32%) of 482 patients, the inflammatory finding (>10 WBCs/hpf) was found in EPS or VB3. Normal WBCs/hpf (<10) was found in 103 (63.98%) of 161 patients with symptoms of chronic prostatitis in whom C. trachomatis was detected in EPS or VB3, in 50 (58.82%) of 85 patients in whom Trichomonas vaginalis was isolated, and in 23 (46.94%) of 49 patients in whom Ureaplasma urealyticum was isolated.  相似文献   
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125.
We present a rectangle-based segmentation algorithm that sets up a graph and performs a graph cut to separate an object from the background. However, graph-based algorithms distribute the graph's nodes uniformly and equidistantly on the image. Then, a smoothness term is added to force the cut to prefer a particular shape. This strategy does not allow the cut to prefer a certain structure, especially when areas of the object are indistinguishable from the background. We solve this problem by referring to a rectangle shape of the object when sampling the graph nodes, i.e., the nodes are distributed non-uniformly and non-equidistantly on the image. This strategy can be useful, when areas of the object are indistinguishable from the background. For evaluation, we focus on vertebrae images from Magnetic Resonance Imaging (MRI) datasets to support the time consuming manual slice-by-slice segmentation performed by physicians. The ground truth of the vertebrae boundaries were manually extracted by two clinical experts (neurological surgeons) with several years of experience in spine surgery and afterwards compared with the automatic segmentation results of the proposed scheme yielding an average Dice Similarity Coefficient (DSC) of 90.97±2.2%.  相似文献   
126.

Introduction

Hieracium s. str. represents one of the largest and most complex genera of flowering plants. As molecular genetics seems unlikely to disentangle intricate relationships within this reticulate species complex, analysis of flavonoids and phenolic acids, known as good chemosystematic markers, promise to be more reliable. Data about pharmacological activity of Hieracium species are scarce.

Objective

Evaluation of the chemosystematic significance of flavonoids and phenolic acids of methanol extracts of aerial flowering parts of 28 Hieracium species from the Balkans. Additionally, investigation of antioxidant potentials of the extracts.

Methods

Comparative qualitative and quantitative analysis of flavonoids and phenolic acids was performed by LC–MS. Multivariate statistical data analysis included non‐metric multidimensional scaling (nMDS), unweighted pair‐group arithmetic averages (UPGMA) and principal component analysis (PCA). Antioxidant activity was evaluated using three colorimetric tests.

Results

Dominant phenolics in almost all species were luteolin type flavonoids, followed by phenolic acids. Although the investigated Hieracium species share many compounds, the current classification of the genus was supported by nMDS and UPGMA analyses with a good resolution to the group level. Hieracium naegelianum was clearly separated from the other investigated species. Spatial and ecological distances of the samples were likely to influence unexpected differentiation of some groups within H. sect. Pannosa. The vast majority of dominant compounds significantly contributed to differences between taxa. The antioxidant potential of the extracts was satisfactory and in accordance with their phenolics composition.

Conclusions

Comparative LC–MS analysis demonstrated that flavonoids and phenolic acids are good indicators of chemosystematic relationships within Hieracium, particularly between non‐hybrid species and groups from the same location. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
127.
The aim of this study was to explore the expression of cancer/testis tumor associated antigens (C/T TAAs) MAGE-A 3/4 and NY-ESO-1 in lung squamous cell carcinoma and adenocarcinoma, and to evaluate their association with the standard clinical-pathological features of surgically treated lung cancer patients. The study included 80 patients with non-small cell lung cancer (40 adenocarcinomas, 40 squamous cell carcinomas) who had undergone surgery in the period between 2002 and 2005. The MAGE-A3/4 and NY-ESO-1 antigen expression was analyzed immunohistochemically (IHC). The results showed MAGE-A3/4 and NY-ESO-1 positive staining in 65.1% and 23.3% of squamous cell carcinomas and 18.9% and 10.8% of adenocarcinomas, respectively. A statistically higher MAGE-A3/4 expression was observed in planocellular bronchial carcinoma (p < 0.001), while no difference was found in the expression of NY-ESO-1 in adenocarcinoma and planocellular carcinoma (p = 0.144). A significant association was found between the MAGE-A3/4 expression and presence of tumor necrosis in squamous cell cancer specimens (p = 0.001), but not in adenocarcinoma (p = 0.033). A statistically significant association was noted between the NY-ESO-1 expression and positive hilar and mediastinal lymph nodes in adenocarcinoma (p = 0.025) whereas it was not the case in squamous cell carcinoma. Non-small cell lung cancer frequently expresses cancer/testis tumor associated antigens. Our results demonstrate that the MAGE-A3/4 and NY-ESO-1 expression was significant associated with prognostic factors of poor outcome of disease (presence of tumor necrosis and lymph node metastasis). As C/T antigens are important for inducing a specific immune reaction in lung cancer patients, there is an intention to form a subgroup of patients in the future, whose treatment would be enhanced by specific immunotherapy based on the observed scientific results.  相似文献   
128.
Double tooth     
The form of primary and permanent teeth can differ morphologically from that which is considered normal, completely or in some parts. The changes in tooth form can be hereditary or caused by some disease or trauma. Fusion is a union of one or more teeth during development. Gemination means that two separate morphological units were created by division of the tooth germ. The intention of this study was to state the prevalence of double teeth (fusion and gemination) among the persons tested, as to gender, distribution in the maxilla or mandible, and whether the anomaly occurred bilaterally or unilaterally. The results of this investigation have shown that in a total of examined 3,517 plaster models, a prevalence of double teeth was 0.2%. 57.2% of them were fusioned and 42.9% geminated.  相似文献   
129.
130.
Previous studies of ferrous wild-type phenylalanine hydroxylase, [Fe(2+)]PAH(T)[], have shown the active site to be a six-coordinate distorted octahedral site. After the substrate and cofactor bind to the enzyme ([Fe(2+)]PAH(R)[L-Phe,5-deaza-6-MPH(4)]), the active site converts to a five-coordinate square pyramidal structure in which the identity of the missing ligand had not been previously determined. X-ray absorption spectroscopy (XAS) at the Fe K-edge further supports this coordination number change with the binding of both cosubstrates to the enzyme, and determines this to be due to the loss of a water ligand.  相似文献   
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