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1.
The main purpose of the present investigation was to study the effect of cloturin on aerobic glycolysis, endogenous and exogenous respiration and the level of ATP in both Ehrlich ascites carcinoma (EAC) and P388 murine leukaemia cells incubated in vitro. Also its effect on the level of total (T-SH) and non-protein (NP-SH) thiol groups was investigated. A significant inhibition of aerobic glycolysis was found only in P388 cells after 60 min of cloturin action. Cloturin inhibited both endogenous and exogenous respiration of EAC with succinate as substrate. Cloturin decreased the level of ATP after 2 h incubation in both types of tumour cell. The level of NP-SH was decreased more than that of T-SH in both types of cell.  相似文献   

2.
Three types of chiral stationary phase were used to achieve chromatographic resolution of enantiomers of rac-11-dihydrooracin (DHO), the principal metabolite of a potential cytostatic drug oracin. Chiralcel OD-R as a chiral stationary phase with mobile phase comprising acetonitrile (modifier) and sodium perchlorate (buffering component) proved to be the most suitable system. Chemometric optimisation based on the Box-Wilson central composite design was employed to find the optimum resolution. The optimum factor space was defined by three parameters: temperature, modifier concentration and buffer concentration. Newly designed chromatographic response functions based on a combination of resolution R(S) and retention time of the last component eluted t(RL) were employed to evaluate the resolution with regard to quality and quantity. Optimum values predicted from those models of response surfaces were in excellent agreement with the experimental results. The chromatographic resolution of DHO enantiomers is suitable for xenobiochemical studies on stereoselectivity and stereospecificity of biotransformation enzymes.  相似文献   

3.
From the first test cross progenies of control (no larval transfers; no ethyl methanesulphonate), physical stress (two larval transfers; no ethyl methanesulphonate) and 0.75% ethyl methanesulphonate (two larval transfers; 0.75% ethyl methanesulphonate)-treated F1 (Oregon K +/dumpy black cinnabar, dp b cn) males ofDrosophila melanogaster, respectively, 6,10 and 52 wild-looking first test cross males were again test crossed to obtain second generation. The overall percentages of male recombination detected in the second test cross progenies, in the three sets of experiments, were statistically the same as those in the first test cross progenies. Thus the enhanced male recombination caused by physical stress (with or without ethyl methanesulphonate) was transmitted to next generation. Non-reciprocal male recombination was observed indp b but not inb cn region in both first and second test cross progenies. Three abnormalities, (i) production of wild-type flies in majority overdp b cn type, (ii) Non-Mendelian segregation atdp b andcn loci and (iii) sex-ratio differences fordp bcn and +b cn types observed in test cross progenies of F1 males ofDrosophila melanogaster were transmitted to next generation when induced with 0.75 % ethyl methanesulphonate but not when these abnormalities were induced with physical stress. The data suggest possible association of non-reciprocal male recombination, segregation distortion and sex-ratio imbalance inDrosophila melanogaster. In fact these may be representing different aspects of the same phenomenon  相似文献   

4.
Background: Rapid urease test (CLO‐test) is an inexpensive and quick method for diagnosis of Helicobacter pylori infection with controversial results in children. We evaluated the performance of CLO‐test in relation to endoscopic and histological findings in children with H. pylori infection. Materials and methods: We studied the medical records of c hildren with H. pylori infection who were diagnosed between 1989 and 2009. Noninfected children were used as controls. H. pylori infection was defined by positive culture or by two other positive tests (histology and CLO‐test, or urea breath test when a single test was positive). All children had histology together with CLO‐test. Tissue culture was performed whenever possible. Results: Five hundred thirty infected children (10.4 ± 3.0 years) and 1060 controls (7.3 ± 4.4 years) were studied. Sensitivity of CLO‐test was 83.4% (95% CI, 79.9–86.3%), of culture 84.6% (95% CI, 78.7–89.1%), of histology 93.2% (95% CI, 90.7–95.1%), and specificity 99% (95% CI, 98.2–99.4%), 100%, and 100% respectively. CLO‐test positivity was correlated with higher bacterial density (p < .001), activity (p < .001) and severity of gastritis (p < .01), older age (p < .01), and the presence of antral nodularity (p < .001). When CLO‐test was positive, the concordance with histology and culture was high (95.5 and 89.2% respectively), whereas low concordance was observed when CLO‐test was negative (17.05 and 45.83% respectively). Conclusions: CLO‐test had lower sensitivity and comparable specificity with histology. Both tests should be performed concurrently to accurately diagnose H. pylori infection in children.  相似文献   

5.
Objective The aim of our study was to evaluate the accuracy of the serology test kit (Signify H. pylori test), an office-based serological test and to compare relative performances with endoscopy, including biopsy urease tests (Clotest), histology, and culture when applied to dyspeptic adult patients in Hong Kong Chinese. Methods Prospective clinical trial was conducted at the Alice Ho Miu ling Nethersole Hospital (AHNH) outpatient endoscopy center from June to December 2004 and included adult Chinese patients who attended the endoscopy center. A research nurse interviewed consenting patients and whole blood samples were obtained via simple fingerstick were then and transferred to Signify test kits. The results were read after 5 minutes. The presence of two distinct lines within the result-reading window was treated as a positive result; a single distinct line was treated as a negative result. All patients underwent upper gastroduodenal endoscopy, and antral/antrum gastric biopsy specimens were taken and then processed for microbiological cultures. Results A total of 384 patients were recruited in the study and 131 (34.7%) patients were tested positive for H. pylori. Among them, 62 patients (47.3%) were detected by the Signify H. pylori test. The Signify serology test kit was 52.7% sensitive, 87.9% specific, and 75.7% accurate, respectively in the current study. Conclusion The Signify H. pylori test showed a sub-optimal correlation between the presence of H. pylori infection and the serological test results in a Hong Kong Chinese population.  相似文献   

6.
From April to July 2003 and 2004, we surveyed the nest-site selection of the White Eared pheasant (Crossoptilon crossoptilon) in the Zhujie Monastery and in the mountain facing it in Sichuan Province, China. In this paper, we studied the nest characteristics and the clutch size of the pheasant. Habitat sampling method was used to determine the variables that might affect the nest-site selection of the White Eared pheasant. Chi-square test was used to identify which habitat type was likely to be preferred by the bird. Independent-samples t test and Mann-Whitney U test were used to find which variables were important for the birds’ nest-site selection. A total of 13 nests were found. Oak shrub was greatly preferred as nest sites (84.62%). Nests under a rock wall (7.69%) and a fallen tree (7.69%) were also found. The average clutch size of a White Eared pheasant is 7.33±0.54 (range, 5–11; n=12). Laying period was between April 27 and May 21. In the Zhujie area, 1 nest was in the forest and 11 nests were in oak shrubs. The species preferred oak shrub as its nesting habitat (χ 2=8.333, df=1, P<0.05). The bird was more likely to place its nest in sites with a high coverage, i.e. 0.5, 1, and 2 m above the ground (independent-samples t test, P<0.05), and with a large shrub diameter (Mann-Whitney U test, P<0.05). The species are more likely to prefer sites with plant cover, shrub cover (independent-samples t test, P<0.05), and shrub height (Mann-Whitney U test, P<0.05) in a relatively small range. Translated from Journal of Beijing Normal University (Natural Science), 2005, 41(2) (in Chinese)  相似文献   

7.
Background and Aims: To assess the validity of biopsy‐based tests (histology, culture, and urease test) and serology in detecting current H. pylori infection for the peptic ulcer patients who had gastric bleeding. Methods: A total of 398 peptic ulcer patients were enrolled and divided into two groups, according to the presence or absence of bleeding. The diagnosis for current H. pylori infection was verified using the gold standard combining individual H. pylori tests. Sensitivity, specificity, and positive and negative predictive values of the culture, Campylobacter‐like organism (CLO) test (urease test), histology, and serology were compared. Results: Of the total study population (N = 398), 157 (39.4%) patients were categorized into the bleeding group. The sensitivities of the culture (40.0%) and CLO (85.0%) in the bleeding group were significantly lower than culture (58.1%) and CLO (96.4%) in the nonbleeding group (p = .012 and p < .001, respectively). In the bleeding group, the sensitivity of CLO (85.0%) was significantly lower than histology (92.5%) and serology (97.4%) (p = .013 and p = .002, respectively), which was not found in the nonbleeding group. The specificity of serology in the bleeding group (56.3%) was significantly lower than that of nonbleeding group (74.2%) (p = .038). Similarly, the specificity of serology was significantly lower than the other H. pylori tests in the bleeders. Conclusions: Bleeding decreased the sensitivity of H. pylori tests in patients with peptic ulcer, especially in urease test or culture. In contrast, histology was found to be a quite reliable test, regardless of the presence of bleeding.  相似文献   

8.
A test of the irregular echinoid Hemipneustes striatoradiatus (Leske) was dissolved in dilute hydrochloric acid to expose the flint steinkern. This revealed slender, string-like borings that were mainly limited to ambulacra (Talpina isp. cf. T. canna (Price)); less common pouch-like borings limited to part of one ambulacrum only (Rogerella isp. cf. R. pattei (Saint Seine)); and slender, sinuous to contorted burrows, Planolites montanus Richter. Ingress to the test (borers) and sediment infill (burrowers) was presumably through the ambulacral pore pairs of the dead test. Borings and burrows were probably not coeval. Such infestations of fossil echinoids may be locally common, but their identification is controlled by the difficulty of seeing features of both the test and the infill.  相似文献   

9.

This study was to evaluate the effect of Streptococcus salivarius K12 on tongue coating–associated halitosis. Twenty-eight subjects having tongue coating–associated halitosis were randomly divided into either a test or control group. For each of the 30 days, the test subjects sucked S. salivarius K12 tablet while the control subjects sucked placebo tablets. All the subjects did not take physical (tongue scraping) and chemical (antiseptic mouth-rinse) oral cavity pretreatment prior to use of the tablets. At baseline, and on the 1st, 7th, and 14th day after completing the course of tablets, the subjects were assessed for their organoleptic test (OLT) scores, volatile sulfur compound (VSC) levels, and tongue coating scores (TCS). During the course, all subjects kept their routine oral care habits without scraping their tongue coating. Plaque index, probing depth, and bleeding index were recorded at baseline and at the completion of the trial. On the 1st day following the end of tablet use, the OLT scores and VSC levels had significantly decreased in the test group when compared with the baseline values (P = 0.001 and P = 0.012). The TCS in the test group were also significantly decreased (P = 0.05). At days 7 and 14, the OLT scores in the test group were still significantly lower than the baseline levels (P = 0.006 and P = 0.039 respectively). However, there were no statistical differences with OLT, VSC, and TCS between the test group and the placebo group by analysis of multi-level regression model. The use of S. salivarius K12 did not have significant effect on halitosis with tongue coating cause when the tongue coating was not physically or chemically pre-treated, which implies removing tongue coating is required before Streptococcus salivarius K12 use.

  相似文献   

10.
Three different bioassays, two culture tube test methods with respectively Stigeoclonium tenue or Scenedesmus quadricauda and one bottle test with S. quadricauda, were compared. The yields obtained in the various tests were linearily correlated (r = 0.86, P < 0.001). The same primary limiting nutrient was indicated by the bioassays in most cases. However the algal growth in the tube test using Stigeoclonium was more often P-limited. In the case of S. quadricauda both test methods (tube and bottle) were nearly equally effective. The yields of N-limited samples were significantly correlated with the inorganic-N as well as total-N concentration of the water sample. A significant correlation of the ortho-P as well as total-P concentration with the yield of the P-limited assays was only found for Stigeoclonium tenue. The critical total N/P ratio (by weight) for N or P limitation was approximately 17: 1 for Stigeoclonium tenue and 22: 1 for Scenedesmus quadricauda.  相似文献   

11.
Two different kits for the detection of serum cryptococcal antigen in patients with pulmonary cryptococcosis were evaluated. The Eiken test (the Eiken Co., Tokyo), which uses pronase for pretreatment of serum, was compared with the Crypto-LA test (International Biological Laboratories, Cranbury, NJ), which did not use pronase prior to testing. Cryptococcal antigen was detected in 21 of 23 patients (91%) with the Eiken test and in only 10 of 23 patients (43%) with the Crypto-LA test (p<0.01 by Mcnemar test). However, the sensitivity of two tests was identical without use of pronase, as both tests could detect as little as 104 cells/ml ofCryptococcus neoformans and 10 ng/ml of capsular polysaccharide ofC. neoformans. In those serum specimens for which both tests were positive, titers were much higher for the Eiken test, but there was a statistically significant correlation between the two tests (coefficient correlation 0.79,p<0.01). Cryptococcal antigen titer levels measured by the Eiken test correlated well with clinical courses. There was one false-positive reaction among 82 sera of non-cryptococcal patients. Pronase enhanced the sensitivity of the Eiken test, which appeared to be useful in patients with pulmonary cryptococcal disease, and its use may prevent unneeded lung biopsies.  相似文献   

12.
A total of six male and six female sprinters at the same national competition level and aged 18–20 years performed a force/velocity test and a 30-s supramaximal exercise test (Wingate test) on 2 different days, separated by a maximal interval of 15 days. The maximal anaerobic power (W max) was determined from the force/velocity test, and the mean anaerobic power (W) from the Wingate test. Immediately after the Wingate test, a 5-ml venous blood sample was drawn via a heparinized catheter in an antebrachial vein for subsequent catecholamine (adrenaline and noradrenaline) analysis. After 5 min recovery a few microlitres of capillary blood were also taken for an immediate lactate determination. Even expressed per kilogram lean body mass,W max andW were significantly lower in women. The lactate and adrenaline responses induced by the Wingate test were also less pronounced in this group whereas the noradrenaline levels were not significantly different in men and women. Above all, very different relationships appeared between lactate, adrenaline, noradenaline and W according to sex. Thus, as reported by other authors, the adrenergic response to a supramaximal exercise seemed to be lower in women than in men. Nevertheless a different training status between the two groups, even at same national competition level, could not be excluded and might contribute, at least in part, to the gender differences observed in the present study.  相似文献   

13.
Two pools of isothiocyanate fluorescein-conjugated rabbit antisera toBacteroides fragilis, B. thetaiotaomicron, B. vulgatus, B. distasonis, B. ovatus, and toB. melaninogenicus, subsp.melaninogenicus andintermedius, andB. asaccharolyticus, respectively, were used in immunofluorescent (IF) tests of smears of 122 clinical specimens from a variety of sources, including abscesses and wounds. Smears of broth medium of 14 blood cultures were also tested. Bacteria of the species and subspecies mentioned were detected by the IF tests in 100 and by culture studies in 106 of the 136 speciments tested. Results of the culture studies indicated that 6 tests were false-negative by the IF test, while no false-positive tests were found. The sensitivities of the two test kits were 97% and 85%, respectively, while their specificities were 100%. The predicted value for a positive test with any of the two pools of antisera was 100%, while the predicted value for a negative test was 93% and 97%, respectively. The use of the two test kits (Fluoretec F and M) was found to be a valuable means for a rapid diagnosis of human infections with theBacteroides species mentioned.  相似文献   

14.
15.
Phytochemical investigations were performed on the EtOAc-soluble fraction of the whole plant of the sky flower (Duranta repens) which led to the isolation of the iridoid glycosides 16. Their structures were elucidated by both 1D and 2D NMR spectroscopic analysis. All the compounds showed potent antioxidative scavenging activity in four different tests, with half maximal inhibitory concentration (IC50) values in the range 0.481–0.719?mM against DPPH radicals, 4.07–17.21 µM for the hydroxyl radical (?OH) inhibitory activity test, 43.3–97.37 µM in the total reactive oxygen species (ROS) inhibitory activity test, and 3.39–18.94 µM in the peroxynitrite (ONOO?) scavenging activity test. Duranterectoside A (1) displayed the strongest scavenging potential with IC50 values of (0.481?±?0.06?mM, 4.07?±?0.03, 43.30?±?0.05, 3.39?±?0.02?µM) for the DPPH radicals, ?OH inhibitory activity test, total ROS inhibitory activity test and the ONOO? scavenging activity test, respectively.  相似文献   

16.
Bruns  Eric  Egeler  Philipp  Roembke  Joerg  Scheffczyk  Adam  Spoerlein  Peter 《Hydrobiologia》2001,463(1-3):185-196
The uptake of chemicals in soil organisms, especially earthworms, has been studied many times. However, in Europe no internationally accepted standardised test guideline for the assessment of bioaccumulation in the soil ecosystem exists. Therefore, the German Federal Environmental Agency recently funded a project in which a standardisable test method for measuring bioaccumulation of chemicals using earthworms and enchytraeids is being developed. In this contribution, initial results with the new method are presented, using two model chemicals (the insecticide lindane and the fungicide hexachlorobenzene). Two enchytraeid species (Enchytraeus luxuriosus and Enchytraeus albidus) were selected as test organisms due to their easy handling and their important ecological role in the soil compartment. Artificial soil and a natural standard soil were used as test substrates. Test concentrations were based on previous results of acute and reproduction toxicity tests performed with the same species. Uptake as well as the elimination of the test substances were examined under standardised conditions in a closed test system. The first results show that both chemicals were accumulated considerably by both enchytraeid species. The bioaccumulation factors (BAFs) of lindane and hexachlorobenzene found for enchytraeids are significantly higher compared to those for lumbricid earthworms. Evaluation of the preliminary data suggests that the smaller species E. luxuriosus accumulated the two chemicals to a greater extent than E. albidus. In most cases, both chemicals were eliminated completely. The use of this new test method appears suitable for the ecotoxicological risk assessment of bioaccumulative chemicals.  相似文献   

17.
Sera from 17 patients of scrub typhus in the acute and convalescent phases were tested by indirect immunoperoxidase test, Weil-Felix (WF) test, enzyme-linked immunosorbent assay (ELISA), and immunoblotting. In the comparison of antibody titers between acute- and convalescent-phase sera, we recognized a parallelism of increment between the titers in WF test and titers of immunoglobulin M (IgM) in ELISA against Proteus mirabilis strain OXK-whole cells and OXK-lipopolysaccharides (Proteus OXK-LPS). Furthermore, IgM antibodies from almost all of WF test-positive sera recognized LPS from Proteus OXK in immunoblotting. Based on these results, it was concluded that IgM antibody rather than IgG may participate in WF test, and that Proteus OXK-LPS may have one of antigenic epitopes common to the components of R. tsutsugamushi.  相似文献   

18.
Two laboratory methods of testing for resistance to Botrytis squamosa in Allium cepa, A. fistulosum and hybrid material derived from them were developed. In one method, seedlings were sprayed with conidiospores, incubated for 3 days at 15°C (2 days at 100% r.h.) and the numbers of lesions per leaf assessed. This test was destructive. The second method was non-destructive, the plants being retained for breeding purposes. Leaf segments (25 × 15 mm) or leaf discs (14 mm diameter) were inoculated individually with a drop (0·014 ml) of spore suspension, and maintained at 15°C and 100% r.h. with a 12 h photoperiod. The length of the latent period, denned as the number of days for 50% of the leaf portions to produce lesions bearing visible mycelium, was determined for each onion line in a test. The reciprocal (1/t) of the latent period was used to test for significant differences between lines by analysis of variance. With both test methods, spores were applied at concentrations that discriminated relative resistance most readily. In both seedling and leaf segment tests A. fistulosum was more resistant than A. cepa to B. squamosa. The leaf disc test indicated that cultivars of A. fistulosum differed in their resistance. In hybrid material resistance was intermediate or more like that of A. fistulosum.  相似文献   

19.
Stingrays (Order: Myliobatiformes) are well‐known predators that feed on a variety of marine species including crustaceans, teleosts, molluscs and annelids. Here, a predatory attack by a stingray on the large spatangoid echinoid Meoma ventricosa (Lamarck) is reported from the shallow‐water carbonate platform of San Salvador, Bahamas. A single stingray was observed feeding on a large adult specimen of M. ventricosa near Sand Dollar Beach, San Salvador Island. The partially crushed and partially eviscerated test of the attacked echinoid was collected from the feeding site. In addition, a crushed test of a freshly killed, smaller irregular clypeasteroid echinoid Leodia sexiesperforata (Leske) was also recovered at the same site. In both cases, the test was broken across the test plates and not along plate boundaries. Meoma ventricosa showed major plate loss on the oral side; however, bite traces and spine loss were not observed in the damaged areas. Similarly, L. sexiesperforata showed no evidence of spine removal; however, bite marks were identifiable. The observed test damage in both taxa is morphologically distinct and could be potentially identifiable in the fossil record.  相似文献   

20.
Leptospires were isolated from 24 of 327 (7%) muskrats (Ondatra zibethicus) caught in The Netherlands. All isolates were identified asLeptospira interrogans. One isolate was typed as serovarcopenhageni in the Icterohaemorrhagiae serogroup, one as serovarlora in the Australis serogroup. Twenty-one isolates showed a close relationship with serovarsgrippotyphosa, valbuzzi, muelleri andratnapura from the Grippotyphosa serogroup. One isolate was lost. Sera from 196 muskrats were examined by the microscopic agglutination test. Forty-five (23%) sera reacted positively (titers1: 160), 42 (21%) of these 45 sera to Grippotyphosa and 3 (2%) to Sejroe serogroup antigens. This is the first report of serological and cultural evidence of leptospira infection in muskrats in The Netherlands.Abbreviations CAAT cross agglutination absorption test - 5-FU 5-fluorouracil - MAT microscopic agglutination test - MCA monoclonal antibodies - PBS phosphate buffered saline - REA restriction endonuclease analysis - SDS sodium dodecyl sulphate  相似文献   

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