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排序方式: 共有147条查询结果,搜索用时 265 毫秒
1.
Ante M. Krstulovi Laura Bertani-Dziedzic Sandra Bautista-Cerqueira Stanley E. Gitlow 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1982,227(2):379-389
We describe a direct analysis for the simultaneous quantitative determination of 4-hydroxy-3-methoxyphenylacetic (homovanillic) acid and other monoamine metabolites in human lumbar cerebrospinal fluid, utilizing reversed-phase high-performance liquid chromatography with amperometric detection. In addition, a rapid isocratic separation was developed for homovanillic acid in the presence of other endogenous compounds.Twenty-five unselected diagnostic specimens of human lumbar cerebrospinal fluid were extracted with ethyl acetate and subsequently analyzed using the described method. Chromatographic peaks were identified on the basis of retention behavior and ratio of responses at several oxidation potentials.Although our quantitative results correlate well with the literature values, the data were not interpreted clinically since samples were obtained from routine, diagnostic testing of patients admitted to the medical or neurologic services at the Mount Sinai Hospital. 相似文献
2.
Matthew J. Friedman Ante M. Krstulović Henri Colin Georges Guiochon Kathleen Pajer 《Analytical biochemistry》1984,142(2):480-486
Described in this paper is a rapid, isocratic assay for serum indole-3-acetic acid (IAA). The sample preparation involves only protein precipitation using sulfosalicylic acid, and the sensitivity of amperometric detection is in the picogram range. The chromatographic analysis time is approximately 4 min. The devised method was used for a longitudinal study of IAA levels in serum samples from control subjects and newly abstinent alcoholics. Dietary variations were eliminated by administering a 2.0-g loading dose of L-Trp to all subjects investigated. The results are presented in the form of cumulative frequency polygons. Preliminary data indicate no differences in IAA levels between newly abstinent alcoholics and control subjects. 相似文献
3.
Antoncić I Dunatov S Bralić M Perković O Coklo M Jurjević A 《Collegium antropologicum》2011,35(2):483-486
Intravenous (i.v.) thrombolysis with recombinant tissue plasminogen activator (rt-PA) is the only available pharmacological therapy to improve the outcome of acute ischemic stroke. We compared 71 patients presenting with ischaemic stroke and given intravenous rt-PA (0.9 mg/kg total dose) within 3 h with 71 patients who present to the hospital more than 3 hours after stroke symptom onset. The primary endpoint was the modified Rankin scale (mRS) at 90 days, dichotomised for favourable and unfavourable (score 2-6). Outcome measures were symptomatic intracerebral haemorrhage within 36 h (haemorrhage associated with National Institutes of Health Stroke Scale [NIHSS] > or = 4 points deterioration), and mortality at 3 months. More patients had favourable outcome with the rt-PA-treated group than with the control group (64.79% vs. 22.54%; p = 0.0001). The greater proportion of patients left with minimal or no deficit 90 days after rt-PA treatment, as compared with the control group. In the treated group symptomatic intracranial hemorrhage occurred in 1 patient who recovered to a level of functional independence, and asymptomatic intracranial hemorrhage was observed in 2 patients. Our experience of an acute stroke thrombolysis service shows that we are able to provide this treatment safely and in accordance with established treatment guidelines. We recommend thrombolytic treatment in acute ischemic stroke for selected population. 相似文献
4.
The efficiency of protected areas (PAs) has often been questioned due to global decline of biodiversity. Invertebrates, especially insects, have been historically underrepresented in conservation studies. Our study focuses on hoverflies, an important group of insect pollinators and proven to be good bioindicators. Research was focused in Serbia, one of Europe's hotspots of hoverfly diversity, with a long tradition of hoverfly research, which provided sufficient information for achieving our aims: identifying areas of high hoverfly diversity, evaluating the efficiency of PAs and prime hoverfly areas (PHAs) in the conservation of hoverflies, determining how well they cover the distribution of hoverfly species, especially those of conservation concern, and testing the importance of the size of the area for conservation of hoverfly diversity. We applied weighting of the species to help stress the importance of species of conservation concern. The results indicated that PHAs cover the areas with high hoverfly diversity better than PA networks, especially when it comes to species of conservation concern. Generalized linear model results showed that the area size was a significant predictor of number of species in both PA and PHA. This indicates that area size is key when designating new areas important for conservation, but there are also other factors that need to be taken into account, such as habitat quality or suitability. Studies like this are useful in aiding designation of new areas important for conservation of certain species and in identifying sampling gaps, which could potentially aim future research in that direction. 相似文献
5.
A new hoverfly species, Cheilosia barbafacies Vujić & Radenković sp. n. (Diptera, Syrphidae), is described and distinguished from the closely related species Cheilosia pascuorum Becker, 1894, based on material collected from the mountains of the Balkan Peninsula. Diagnostic characteristics and an identification key for the members of the proxima group of Cheilosia s. str., including the new taxon, are provided. 相似文献
6.
Szilvia Kusza Katalin Priskin Ante Ivankovic Bogumila Jedrzejewska Tomasz Podgorski András Jávor Sándor Mihók 《Biological journal of the Linnean Society. Linnean Society of London》2013,109(1):54-65
The aim of this work was to gather information about the origin and genetic characterization of the Central European Hucul horse based on 71 horses using 17 microsatellites and the D‐loop region of mtDNA. Their genetic relationship to the Polish Konik (N = 7), German (N = 4) and Hungarian wild Przewalski horses (N = 4) and 200 horse sequences from GenBank was also analysed. Both microsatellite and mtDNA analysis showed a high genetic variation in the Hucul. A total of 130 alleles were detected, the mean number of observed alleles per microsatellite was 7.647, and the number of effective alleles was 4.401. The average observed and expected heterozygosity were 0.706 and 0.747, respectively. The high heterozygosity values and Wright's fixation index (FIS) (?0.128) indicated a low level of inbreeding, low or no selection pressure, and large number of alleles. mtDNA analysis revealed 18 haplotypes for the Hucul population with a total of 23 variable sites. Haplotype and nucleotide diversities were 0.935 ± 0.011 and 0.022 ± 0.012, respectively. Neutrality tests (Tajima's D and Fu's Fs) were non‐significant, and mismatch distribution was ragged, indicating that the Hucul population is in genetic equilibrium. The most frequent mtDNA D‐loop region belonged to haplogroup A (48%), which was also present in Przewalski Wild horse samples, while Polish Konik samples belonged to three haplotypes and C, F, and G haplogroups. Large and significant pairwise ΦST values along with a small number of common haplotypes indicated a low level of gene flow and lack of genetic structure among the three studied breeds (Hucul, Konik, and Przewalski Wild horse). The present work contributes to our knowledge of the genetic diversity of the Hucul horse and helps to define its genetic conservation. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109 , 54–65. 相似文献
7.
The whole brain free fatty acid (FFA) level, as well as the activities of superoxide dismutase (SOD) and glutathione peroxidase (GPX) were determined in the frontal cortex, cerebellum, hippocampus, and pons-medulla region of the single pentylenetetrazol (PZT)-treated and PZT-kindled Hannover-Wistar rats. PZT administration in the convulsive dose caused significant increase of the brain FFA content. Decreased SOD activity was detected in the frontal cortex of PZT-kindled rats, whereas decreased GPX activity was found in the frontal cortex and cerebellum of all treated rats, as well as in the hippocampus and pons-medulla of PZT-kindled rats. Kindling caused distinctive change of antioxidative defense in the frontal cortex, hippocampus, and pons-medulla region. 相似文献
8.
Ante Jerkovic Alison M. Kriegel John R. Bradner Brian J. Atwell Thomas H. Roberts Robert D. Willows 《Plant physiology》2010,152(3):1459-1470
Bran from bread wheat (Triticum aestivum ‘Babbler’) grain is composed of many outer layers of dead maternal tissues that overlie living aleurone cells. The dead cell layers function as a barrier resistant to degradation, whereas the aleurone layer is involved in mobilizing organic substrates in the endosperm during germination. We microdissected three defined bran fractions, outer layers (epidermis and hypodermis), intermediate fraction (cross cells, tube cells, testa, and nucellar tissue), and inner layer (aleurone cells), and used proteomics to identify their individual protein complements. All proteins of the outer layers were enzymes, whose function is to provide direct protection against pathogens or improve tissue strength. The more complex proteome of the intermediate layers suggests a greater diversity of function, including the inhibition of enzymes secreted by pathogens. The inner layer contains proteins involved in metabolism, as would be expected from live aleurone cells, but this layer also includes defense enzymes and inhibitors as well as 7S globulin (specific to this layer). Using immunofluorescence microscopy, oxalate oxidase was localized predominantly to the outer layers, xylanase inhibitor protein I to the xylan-rich nucellar layer of the intermediate fraction and pathogenesis-related protein 4 mainly to the aleurone. Activities of the water-extractable enzymes oxalate oxidase, peroxidase, and polyphenol oxidase were highest in the outer layers, whereas chitinase activity was found only in assays of whole grains. We conclude that the differential protein complements of each bran layer in wheat provide distinct lines of defense in protecting the embryo and nutrient-rich endosperm.Wheat grain (Triticum aestivum) is a major cereal crop and staple food in many parts of the world. The endosperm is the main nutritional component and is extracted in milling to produce base ingredients such as flour and semolina. Crop yield and quality may be compromised by both environmental and biological stresses. Wheat varieties are known to vary in their resistance to such stresses, probably due to individual differences in defense protein levels (Demeke and Morris, 2002; Bonnin et al., 2005; Yarullina et al., 2005). Cereal grain contains many defense proteins that have been categorized according to their mode of action and structural similarities. A major class of these is the pathogenesis-related (PR) proteins, which include PR-1, PR-2 (β -1,3-glucanases), PR-3 (chitinases), PR-4 (wheatwin1), and PR-5 (thaumatin-like proteins; Selitrennikoff, 2001; Desmond et al., 2006). Other known defense proteins are xylanase inhibitor proteins (XIPs) and α -amylase inhibitor proteins (Mundy et al., 1984; Payan et al., 2003). All of these defense proteins have both general and specific roles that contribute to plant survival, although little is known of their location within the various grain tissues, particularly the multiple layers that constitute bran.Proteomic analysis of wheat grain has previously been applied to identify proteins in the germ and endosperm (Skylas et al., 2000; Wong et al., 2004; Mak et al., 2006), but analysis of bran and bran tissue fractions has not been reported. Collection of sufficiently pure bran tissue fractions has limited progress, mainly due to the strong bonds between the various bran tissue layers and endosperm in dry grain. Thus, a method to obtain bran layers free from contaminants, such as adjacent tissue and endosperm, is required to provide a sample suitable for proteomic analysis. Soaking whole grain in water causes the endosperm to soften, allowing it to be easily removed and washed from the bran; the bran becomes malleable enough to dissect. While this approach might not identify the proteome of dry grain fractions, it is the best available representation of the three distinct tissue fractions in grains, namely the outer layer (epidermis and hypodermis), intermediate layer (cross cells, tube cells, testa, and nucellar tissue), and inner layer (aleurone cells; Antoine et al., 2003, 2004). Using this method, water-soluble proteins that diffuse from the grain can be collected and identified.In this study we aimed (1) to dissect bran into the three separate tissue fractions described above and to identify the protein complement of each fraction using proteomics, (2) to confirm the location of three major defense proteins identified (one from each microfraction) using immunolocalization, and (3) to identify water-soluble proteins and assay any defense-related proteins for enzymatic activity. 相似文献
9.
The aim of the study was to determine the impact of demographic and anthropometric parameters on the gastric myoelectrical activity characteristics in a healthy Croatian population. The influence of age, sex, body mass index (BMI) and menstrual cycle phase on the gastric myoelectrical activity characteristics was assessed. The study included 120 healthy subjects of both sexes (60 male and 60 female), divided into four age groups (18-35, 36-50, 51-65 and > 65 years) and three BMI groups (BMI < 25, 25-30 and > 30). Female subjects of reproductive age were divided into three groups according to menstrual cycle phase (day 1-3, day 4-8 and day 9-20 of menstruation). All study subjects underwent percutaneous electrogastrography (EGG) for 60 min before and 60 min after a test meal. The following parameters of the gastric myoelectrical activity were observed: dominant frequency (DF); dominant frequency within normal range (DFNR, %); coefficient of variation for dominant frequency (CVDF); dominant strength (DS. mV); postprandial increase intensity in dominant strength (PPIIDS, %); bradygastria (BG, c/min, %); tachygastria (TG, c/min, %); and arrhythmia (AR). Age was found to influence preprandial but not postprandial DFNR, CVDF and AR. Sex influenced preprandial DF, CVDF, DS and BG, and postprandial DF, CVDF, PPIIDS and TG. BMI exerted an impact on preprandial TG and AR, and postprandial DF, CVDF and AR. The phase of menstrual cycle influenced DF in preprandial period and none of EGG parameters in postprandial period. 相似文献
10.
Stimac G Dimanovski J Trnski D Katusić J Ruzić B Spajić B Reljić A Padovan M Kraus O 《Collegium antropologicum》2007,31(4):1055-1060
We demonstrate the evolution of the clinical presentation and outcomes for patients with clinically localized prostate cancer (PC) treated with radical retropubic prostatectomy (RRP) at our department, emphasizing epidemiologic significance of changes during the 10-year period. We assessed the annual trends for changes in patients age, preoperative prostate specific antigen (PSA), preoperative versus postoperative stages and Gleason grades, organ confined status and surgical margin status. A total of 488 RRPs were performed from January 1996 to December 2005 with the annual frequency increased from 8 to 129 (1512.5%). Mean patient age increased from 61.5 to 66.12 years in 2005, with the percentage of men aged more than 70 years increased from 12.5 to 26.5%, respectively. The detection of PC based solely on pathological PSA levels (as indication for prostate biopsy) rose impressively from 25.5 to 70% and the rates of postoperative organ-confined disease also increased significantly from 25 to 74.7%. Mean preoperative PSA decreased from 16.7 to 9.89 ng/mL. On the contrary, there was an increase in percentage of patients with preoperative PSA values ranging from 4 to 10 ng/mL (from 20 to 65.4%). Positive surgical margin rate decreased from 49.4 to 25% and percent of patients receiving neoadjuvant therapy decreased from 78.5 to 5.4%. Proportion of patients who were undergraded decreased from 75.1 to 31.7%. The rates of understaging have remained relatively stable over the years. During the study period, PC was increasingly detected by prostate biopsy on the basis of a pathological PSA level only and shifted significantly to more organ-confined stages with more favourable outcomes for pathological variables due to a more accurate assessment of clinical stage prior to surgery, reduced use of neoadjuvant therapy and improved surgical technique. Our data also argue strongly that routine PSA testing should be expanded and not restricted. 相似文献