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1.
DENNIS M. DWYER 《The Journal of eukaryotic microbiology》1974,21(1):139-145
Antigens prepared from Trichomonas gallinae, Histomonas meleagridis, Dientamoeba fragilis, Entamoeba invodens and Entamoeba histolytica were separated by electrophoresis in agar gels and reacted with antisera prepared in rabbits against each of the 5 species. The most numerous and strongest precipitin lines were obtained from reactions between the homologous antigens and antisera. Direct and cross-absorption reaction methods were employed with each antiserum and the various antigens to ascertain quantitatively the immunologic relationships among the several organisms. Trichomonas shared many common antigens with Histomonas, fewer with Dientamoeba and none with either species of Entamoeba. Histomonas was more closely related antigenically to Dientamoeba than to Trichomonas. The histomonad had only a few weakly cross-reacting antigens in common with the 2 Entamoeba species. Dientamoeba shared the most common antigens with Histomonas, fewer with Trichomonas and the fewest with Entamoeba. Somewhat stronger cross-reactivity was obtained with anti-Dientamoeba serum and E. invadens than between this immune serum and E. histolytica. The 2 species of Entamoeba shared the largest number of common antigens with each other, and to a much lesser extent both species cross reacted with Dientamoeba. Anti-Entamoeba sera had only a few weak cross-reacting precipitins with Histomonas. No antigenic relationship was found between either species of Entamoeba and Trichomonas. 相似文献
2.
Summary
Brassica napus and Brassica juncea were infected with a number of Agrobacterium tumefaciens strains. Tumourigenesis was very rapid and extremely efficient on B. juncea with all but one of the strains. Tumourigenesis on B. napus varied widely. It was very efficient with the nopaline strains, was reduced with the succinamopine strain A281 and was very weak with the octopine strains. The latter observation was confirmed with six different B. napus rapeseed cultivars. The selectivity was due to differences in the virulence of Ti plasmids with B. napus, rather than the tumourigenicity of the T-DNA or virulence of the chromosomal genes associated with the strains. An exception was strain LBA4404. The virulence of the octopine strains was increased by coinfection with more virulent disarmed strains and by induction with acetosyringone. 相似文献
3.
Effects of mutual intercropping on cadmium accumulation by the accumulator plants Conyza canadensis,Cardamine hirsuta,and Cerastium glomeratum 总被引:1,自引:0,他引:1
Hui Xia Dong Liang Fabo Chen Ming'an Liao Yi Tang 《International journal of phytoremediation》2018,20(9):855-861
In this study, three cadmium (Cd) accumulator species (Conyza canadensis, Cardamine hirsuta, and Cerastium glomeratum) were co-cultured in Cd-contaminated soil in pots to study the effects of intercropping on co-remediation. Only C. canadensis intercropped with C. glomeratum, C. hirsuta intercropped with C. glomeratum, and three-species intercropping increased plant biomass compared with their respective monocultures. The treatments of C. canadensis intercropped with C. glomeratum and three-species intercropping increased the Cd contents in roots and shoots of C. canadensis, whereas the other intercropping treatments decreased or had no significant impact on Cd contents. As for Cd accumulation, the treatments of C. canadensis intercropped with C. glomeratum, C. hirsuta intercropped with C. glomeratum, and three-species intercropping increased Cd accumulation in a single plant compared with that of their respective monocultures, whereas other intercropping treatments decreased Cd accumulation in individual plants. Only the treatments of C. canadensis intercropped with C. glomeratum and C. hirsuta intercropped with C. glomeratum increased Cd accumulation in shoots of a single pot compared with that of their respective monocultures. Therefore, C. canadensis intercropped with C. glomeratum and C. hirsuta intercropped with C. glomeratum may improve the phytoremediation efficiency for Cd-contaminated soil. 相似文献
4.
Furha Iram Cossor Lucile L. Adams-Campbell Rowan T. Chlebowski Marc J. Gunter Karen Johnson Robert E. Martell Anne McTiernan Michael S. Simon Thomas Rohan Robert B. Wallace Jessica K. Paulus 《Cancer epidemiology》2013,37(5):742-749
Background: Observational studies have associated metformin use with lower colorectal cancer (CRC) incidence but few studies have examined metformin's influence on CRC survival. We examined the relationships among metformin use, diabetes, and survival in postmenopausal women with CRC in the Women's Health Initiative (WHI) clinical trials and observational study. Methods: 2066 postmenopausal women with CRC were followed for a median of 4.1 years, with 589 deaths after CRC diagnosis from all causes and 414 deaths directly attributed to CRC. CRC-specific survival was compared among women with diabetes with metformin use (n = 84); women with diabetes with no metformin use (n = 128); and women without diabetes (n = 1854). Cox proportional hazard models were used to estimate associations among metformin use, diabetes and survival after CRC. Strategies to adjust for potential confounders included: multivariate adjustment with known predictors of colorectal cancer survival and construction of a propensity score for the likelihood of receiving metformin, with model stratification by propensity score quintile. Results: After adjusting for age and stage, CRC specific survival in women with diabetes with metformin use was not significantly different compared to that in women with diabetes with no metformin use (HR 0.75; 95% CI 0.40–1.38, p = 0.67) and to women without diabetes (HR 1.00; 95% CI 0.61–1.66, p = 0.99). Following propensity score adjustment, the HR for CRC-specific survival in women with diabetes with metformin use compared to non-users was 0.78 (95% CI 0.38–1.55, p = 0.47) and for overall survival was 0.86 (95% CI 0.49–1.52; p = 0.60). Conclusions: In postmenopausal women with CRC and DM, no statistically significant difference was seen in CRC specific survival in those who used metformin compared to non-users. Analyses in larger populations of colorectal cancer patients are warranted. 相似文献
5.
Summary The distributions of five Drosophila species and four components of the microflora have been compared across a total of 48 traps baited with four different fruit and vegetable substrates in two domestic compost heaps in Canberra (Australia). Large and consistent differences are found, both among the Drosophila and among the microbial classes, in their distributions across traps baited with different substrates. Moreover the distribution of each Drosophila species shows a unique set of strong associations with the microbial distributions. Thus the distributions of both D. simulans and D. melanogaster are found to be strongly negatively correlated with the abundance of bacteria while D. simulans is also strongly positively correlated with the titre of fermenter yeasts. D. immigrans is strongly positively correlated both with bacteria and with non-fermenter yeasts. D. hydei is positively correlated with nonfermentery yeasts and D. busckii is negatively correlated with fermenter yeasts. Moulds are the only microbial class not consistently associated with the distribution of any of the Drosophila species. The correlations with the other microbial classes are sufficient to explain the majority of the abundance differences of the Drosophila species among the trap types. It is therefore proposed that the clear partitioning of the fruit resources by the Drosophila is due to their differing primary interactions with the microflora. 相似文献
6.
Luciana Fachini Costa Ana L. Cabello Diego Felipe Alves Batista Sankar P. Chaki Paul de Figueiredo Tatiane Alves da Paixão Allison C. Rice-Ficht Thomas A. Ficht Renato Lima Santos 《Microbiology and immunology》2020,64(11):730-736
Brucellosis is a major zoonotic disease, and Brucella melitensis is the species most often associated with human infection. Vaccination is the most efficient tool for controlling animal brucellosis, with a consequent decrease of incidence of human infections. Commercially available live attenuated vaccines provide some degree of protection, but retain residual pathogenicity to human and animals. In this study, Brucella ovis ∆abcBA (Bo∆abcBA), a live attenuated candidate vaccine strain, was tested in two formulations (encapsulated with alginate and alginate plus vitelline protein B [VpB]) to immunize mice against experimental challenge with B. melitensis strain 16M. One week after infection, livers and spleens of immunized mice had reduced numbers of the challenge strain B. melitensis 16M when compared with those of nonimmunized mice, with a reduction of approximately 1-log10 of B. melitensis 16M count in the spleens from immunized mice. Moreover, splenocytes stimulated with B. melitensis antigens in vitro secreted IFN-γ when mice had been immunized with Bo∆abcBA encapsulated with alginate plus VpB, but not with alginate alone. Body and liver weights were similar among groups, although spleens from mice immunized with Bo∆abcBA encapsulated with alginate were larger than those immunized with Bo∆abcBA encapsulated with alginate plus VpB or nonimmunized mice. This study demonstrated that two vaccine formulations containing Bo∆abcBA protected mice against experimental challenge with B. melitensis. 相似文献
7.
Neil M. Ampel Sara O. Dionne Andrea Giblin Abigail B. Podany John Galgiani 《Mycopathologia》2009,167(4):173-180
Background Mannose-binding lectin (MBL) is a circulating collectin that is part of the innate immune response. We explored the serum
levels of MBL in persons with different forms of coccidioidomycosis.
Methods Serum MBL was measured by ELISA from samples obtained from healthy donors with immunity to Coccidioides, and those with various forms of active coccidioidomycosis. Blood cell specimens from a subgroup of subjects with active
coccidioidomycosis were examined for single nucleotide polymorphisms of the MBL gene and promoter regions.
Results The control group comprised 29 healthy immune subjects. Patient groups with active coccidioidomycosis consisted of 20 patients
with symptomatic primary pulmonary coccidioidomycosis, 26 with non-meningeal disseminated coccidioidomycosis, and nine with
coccidioidal meningitis. The group with active coccidioidomycosis was significantly older and more likely to be male than
the control group (for both, P < 0.001). The mean ± SEM level of serum MBL in the healthy controls was 169.4 ± 28.6 ng/ml, significantly higher than the
79.2 ± 10.9 ng/ml for all active groups (P < 0.001). Moreover, the active coccidioidomycosis group was significantly more likely to have serum MBL level ≤70 ng/ml compared
to the control group (P = 0.001). Genetic analysis in 27 subjects with active coccidioidomycosis revealed marked variation based on race and ethnicity.
Among a subgroup of 10 white, non-hispanic men with active coccidioidomycosis, there was a significant association between
the H and P haplotypes and MBL levels ≤70 ng/ml (P < 0.036 and P < 0.035, respectively).
Conclusions These data suggest that there is an association between low serum MBL levels and symptomatic coccidioidomycosis. 相似文献
8.
Homologous resistance to F. hepatica and T. taeniaeformis and cross resistance between these two parasites was investigated in the rat. Rats given a primary infection with F. hepatica were challenged with either F. hepatica or T. taeniaeformis. Conversely rats given a primary infection with T. taeniaeformis were challenged with either F. hepatica or T. taeniaeformis.Infection with F. hepatica generated significant resistance against challenge with F. hepatica given 9 weeks later. Similarly, infection with T. taeniaeformis protected against challenge with T. taeniaeformis given 6 weeks later. Infection with F. hepatica also generated significant resistance against challenge with T. taeniaeformis given 4, 8 or 9 weeks later. Primary infection with T. taeniaeformis did not protect against challenge with F. hepatica. 相似文献
9.
Bernard A. Eskin Carolyn E. Grotkowski Christopher P. Connolly William R. Ghent 《Biological trace element research》1995,49(1):9-19
This research describes the effects of short-term elemental iodine (I2) and iodide (I−) replacement on thyroid glands and mammary glands of iodine-deficient (ID) Sprague-Dawley female rats. Iodine deficiency
causes atypical tissue and physiologic changes in both glands. Tissue histopathology and the endocrine metabolic parameters,
such as serum TT4, tissue and body weights, and vaginal smears, are compared. A moderate reduction in thyroid size from the ID control (IDC)
was noted with both I− and I2, whereas serum total thyroxine approached the normal control with both I− and I2, but was lower in IDC. Thyroid gland IDC hyperplasia was reduced modestly with I2, but eliminated with I−. Lobular hyperplasia of the mammary glands decreased with I2 and increased with I− when compared with the IDC; extraductal secretions remained the same as IDC with I2, but increased with I−; and periductal fibrosis was markedly reduced with I2, but remained severe with I−. Thus, orally administered I2 or I− in trace doses with similar iodine availability caused different histopathological and endocrine patterns in thyroid and
mammary glands of ID rats. The significance of this is that replacement therapy with various forms of iodine are tissue-specific. 相似文献
10.
Artem Polugrudov Sergey Popov Vasily Smirnov Alexander Panev Ekaterina Ascheulova Ekaterina Kuznetsova 《Biological Rhythm Research》2017,48(6):917-929
Young residents of the European North of Russia with normal body weight (n = 66) were divided into three groups, SJL ≤ 1 h, 1 < SJL ≤ 2 h, and SJL > 2 h, using the Munich ChronoType Questionnaire. Participants consumed a breakfast consisting of pizza ad libitum and rated their appetite sensations using visual analog scales. Participants in three SJL groups consumed the same amount of the ad libitum meal and reported similar levels of satiety and fullness right after food intake (intra-meal satiation). However, participants with SJL > 2 h were found to feel significantly hungrier in comparison with participants with SJL ≤ 1 h. In addition, participants with SJL > 2 h reported a diminished satisfaction with food consumption (inter-meal satiety) during 120 min after test breakfast. Thus, the study demonstrates that SJL appears to be associated with disturbance of appetite regulation in young northerners with normal body weight. 相似文献
11.
Marie Novak 《International journal for parasitology》1984,14(5):497-501
Novak M. 1984. Cross-protection between the metacestodes of Mesocestoides corti and Taenia crassiceps in mice. International Journal for Parasitology14: 497–501. Infection with M. corti generated significant resistance against a challenge with T. crassiceps introduced either 2 or 6 weeks after primary infection. Challenge infection with T. crassiceps did not influence primary infection with M. corti. Infection with T. crassiceps protected significantly against challenge with M. corti given 2 weeks but not 6 weeks after the primary infection. Challenge infection with M. corti significantly suppressed primary infection with T. crassiceps. 相似文献
12.
Peng Qi Yue-ming Chen Hao Wang Meng Fang Qiang Ji Yun-peng Zhao Xiao-juan Sun Yan Liu Chun-fang Gao 《Cancer immunology, immunotherapy : CII》2009,58(9):1433-1440
Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide. The risk for developing HCC increases
with severity of inflammation and fibrosis. Transforming growth factor-β1 (TGF-β1) is most frequently upregulated in tumor
cells. The most studied −509C>T polymorphism of TGF-β1 gene has been associated with colorectal, gynecologic, and lung cancers.
To assess whether this polymorphism in TGF-β1 gene is associated with susceptibility to and/or clinicopathologic characteristics
of HBV-related HCC, a total of 575 patients with chronic HBV infection and 299 healthy volunteers with no evidence of recent
or remote HBV infection were prospectively enrolled. The patients were divided into two groups: those without (n = 196) and those with HCC (n = 379). These 379 HCC patients with chronic HBV infection were designated as cases, the remaining 196 patients without HCC
and 299 healthy volunteers served as disease and healthy controls, respectively. −509C>T polymorphism in the TGF-β1 gene promoter
was studied using restriction fragment-length polymorphism. In addition, tumor tissues of liver (n = 60) were obtained from the studied HCC patients for measurement of TGF-β1 mRNA expression levels. We also assessed the
plasma TGF-β1 levels of HBV patients without (n = 94) or with HCC (n = 136) and healthy subjects (n = 120). In our study group, the risk of HCC in Chinese patients with HBV infection was significantly lower with the TT genotypes
than in those with the CC genotypes at position −509 of TGF-β1 gene (P = 0.01). In addition, in the case group, patients with the CC genotype had a statistically significant higher median plasma
TGF-β1 or liver tumor tissue TGF-β1 mRNA level compared with the individuals with the TT genotype. However, in a subsequent
analysis of the association between this polymorphism and clinicopathological characteristics including tumor number, size,
grade, stage, and invasiveness, there was no significant difference in both the distribution of genotype or allelic frequency
within HCC patients, indicating that −509C>T exchange in TGF-β1 gene may play an important role in the occurrence, not the
progression of HBV-related HCC through influencing plasma concentrations of TGF-β1 or TGF-β1 mRNA expression of liver tumor
tissue. 相似文献
13.
Makoto Daimon Toshihide Oizumi Shigeru Karasawa Kiriko Wada Shinji Susa Isao Kubota Takeo Kato 《Biochemical and biophysical research communications》2009,386(1):26-29
The association of the Ser326Cys polymorphism of the 8-oxoguanine glycosylase 1 (OGG1) gene with type 2 diabetes was examined using a Japanese population (n (M/W): 4585 (2085/2500); age: 62.6 ± 10.9 years). HbA1c levels and frequency of diabetic subjects were significantly higher in subjects with genotypes with Cys allele than in those without (p = 0.032 and 0.037, respectively). Multiple logistic regression analysis showed that genotypes with Cys allele were significantly associated with diabetes (OR: 1.32, p = 0.0289). In subjects whose glucose tolerance was classified by FPG and 2-h PG (n = 1.634), the association was more substantial (genotypes with Cys allele vs. without, OR: 1.70, p = 0.0059; genotypes Cys/Cys vs. Ser/Ser, OR: 2.19, p = 0.0008). In subjects with genotype Ser/Ser, the insulin secretion index, HOMA-β, increased in the subjects with glucose intolerance and decreased in the subjects with diabetes, while, in subjects with genotypes Ser/Cys + Cys/Cys, HOMA-β decreased as the glucose tolerance progressed (p for trend = 0.010). 相似文献
14.
Shuai Yuan Huaping Li Chen Chen Feng Wang Dao Wen Wang 《Journal of cellular and molecular medicine》2021,25(7):3484-3497
Patients with hyperglycemia tend to be susceptible to Coronavirus disease 2019 (COVID-19). However, the association of HbA1c level with outcome of COVID-19 patients was unclear. We performed a retrospective study of 2880 cases of COVID-19 admitted in Tongji Hospital, Wuhan, China, among which 922 had detected the HbA1c levels. We found that COVID-19 patients with either lower levels of HbAlc (3%-4.9%) or higher levels of HbAlc (≥6%) were associated with elevated all-cause mortality. Meanwhile, we observed that HbAlc levels were highly correlated with haemoglobin (Hb) and total cholesterol (TC) (P < .0001), moderately correlated with albumin (ALB) and high-sensitive C reaction protein (hs-CRP) (0.0001 < P<.001), and relatively low correlated with low-density lipoprotein cholesterol (LDL-C) (.001 < P<.01). These associated cofactors might together contribute to the clinical outcome of COVID-19 patients. Furthermore, the mortality was higher in COVID-19 patients with newly diagnosed diabetes mellitus (DM) compared with COVID-19 patients with history of DM. Moreover, in patients with history of DM, the mortality was decreased in patients treated with anti-hyperglycaemic drugs. In summary, our data showed that the in-hospital mortality was increased in COVID-19 patients with lower or higher levels of HbAlc. Meanwhile, initiation of appropriate anti-hyperglycaemic treatment might improve the clinical outcome in COVID-19 patients. 相似文献
15.
Influence of phosphate status on phosphate uptake kinetics of maize (Zea mays) and soybean (Glycine max) 总被引:1,自引:0,他引:1
To obtain plants of different P status, maize and soybean seedlings were grown for several weeks in flowing nutrient solution culture with P concentrations ranging from 0.03–100 µmol P L-1 kept constant within treatments. P uptake kinetics of the roots were then determined with intact plants in short-term experiments by monitoring P depletion of a 3.5 L volume of nutrient solution in contact with the roots. Results show maximum influx, Imax, 5-fold higher in plants which had been raised in solution of low compared with high P concentration. Because P concentrations in the plants were increased with increase in external P concentration, Imax was negatively related to % P in shoots. Michaelis constants, Km, were also increased with increased pretreatment P concentration, only slightly with soybean, but by a factor of 3 with maize. The minimum P concentration, Cmin, where net influx equals zero, was found between 0.06 and 0.3 µmol L-1 with a tendency to increase with pretreatment P concentration. Filtration of solutions at the end of the depletion experiment showed that part of the external P was associated with solid particles.It was concluded that plants markedly adapt P uptake kinetics to their P status, essentially by the increase of Imax, when internal P concentration decreases. Changes of Km and Cmin were of minor importance. 相似文献
16.
Bioprospecting of Saprobe Fungi from the Semi‐Arid North‐East of Brazil for the Control of Anthracnose on Sorghum 下载免费PDF全文
Renata Sousa Resende Cristiane Aparecida Milagres Danielle Rezende Carlos Eduardo Aucique‐Perez Fabrício Ávila Rodrigues 《Journal of Phytopathology》2015,163(10):787-794
Anthracnose, caused by the hemiotrophic fungus Colletotrichum sublineolum, is one of the most important diseases affecting sorghum production worldwide. The main goal of this study was to select saprobe fungi from the semi‐arid north‐east of Brazil that could increase sorghum resistance to anthracnose and investigate this increased resistance at both physiological and biochemical levels. Plants were sprayed with Curvularia inaequalis, Gonytrichum macroladum, Memnoniella levispora, Pithomyces chartarum, Periconia hispidula, Phaeoisaria clematidia, Dictyochaeta heteroderae, Sarcopodium circinatum, Periconia byssoides, Moorella speciosa, Stachybotrys chartarum, Pseudobotrytis terrestres, Memnoniella echinata, Stachybotrys globosa and Gonytrichum clamydosporium 24 h before inoculation with C. sublineolum. Plants sprayed with water served as the control treatment. The area under the anthracnose progress curve was significantly reduced in comparison with the control treatment only for plants sprayed with C. inaequalis. Therefore, C. inaequalis was selected for physiological and biochemical evaluations. The peroxidases, chitinases and β‐1,3‐glucanases activities were significantly higher for plants sprayed with C. inaequalis and inoculated with C. sublineolum than for plants not sprayed with C. inaequalis and inoculated with C. sublineolum. There was no apparent decrease in the values of net carbon assimilation rate, stomatal conductance to water vapour or transpiration rate for plants sprayed with C. inaequalis and infected by C. sublineolum in comparison with plants not sprayed with C. inaequalis and infected by C. sublineolum. In conclusion, sorghum resistance against C. sublineolum infection was greatly potentiated by C. inaequalis without any apparent change in the photosynthetic capacity of the infected plants. 相似文献
17.
Calli were induced from mature caryopses of timothy grass (Phleum pratense L.) on MS medium (Murashige and Skoog 1962) supplemented with 500 mg·dm−3 casein hydrolysate and 5 mg·dm−3 2,4-D (2,4-dicholorophenoxyacetic acid) or 2 mg·dm−3 dicamba (3,6-dichloro-o-anisic acid). Twelve-week-old calli were passaged on media with reduced levels of auxins (2 mg·dm−3 2,4-D or 1 mg·dm−3 dicamba). Tissues induced on medium with 2,4-D were transferred on medium with 2,4-D and on medium with dicamba; parallely
calli initiated on medium with dicamba were passaged on medium with 2,4-D or dicamba. Calli from various media sequences were
used to establish cell suspension cultures in media containing 2 mg·dm−3 2,4-D or 1 mg·dm−3 dicamba. An assessment of regeneration ability of calli was made on MS medium containing 0.2 mg·dm−3 kinetin. Callus tissue induced and/or subcultured on any of the media with 2,4-D did not regenerate plants while dicamba
added to the media was the effective stimulator of regenerability. In the presence of 2,4-D calli and suspensions produced
a jelly-like extracellular matrix. In cell suspension this phenomenon was observed 4–5 days after each passage. The measurements
of electric potential of calli, growing on MS medium with kinetin were performed. Non-regenerating callus areas had an electric
potential close to 0 mV while parts of tissue with meristematic centres were characterized by lower values of electric potential. 相似文献
18.
In a period cross‐sectional study performed to examine ectoparasites on 340 stray cats in Jerusalem, Israel, 186 (54.7%) were infested with the cat flea, Ctenocephalides felis (Siphonaptera: Pulicidae), 49 (14.4%) with the cat louse, Felicola subrostratus (Phthiraptera: Trichodectidae), 41 (12.0%) with the ear mite, Otodectes cynotis (Astigmata: Psoroptidae), three (0.9%) with the fur mite, Cheyletiella blakei (Trobidiformes: Cheyletidae), two (0.6%) with the itch mite Notoedres cati (Astigmata: Sarcoptidae), and 25 (7.3%) with ticks of the species Rhipicephalus sanguineus sensu lato (Ixodida: Ixodidae), Rhipicephalus turanicus or Haemaphysalis adleri (Ixodida: Ixodidae). A higher number of flea infestations was observed in apparently sick cats (P < 0.05) and in cats aged < 6 months (P < 0.05). The proportion of flea‐infested cats (P < 0.01), as well as the number of fleas per infested cat (P < 0.01), was higher in autumn than in other seasons. By contrast with findings in cats with flea infestations, rates of infestation with ticks were higher amongst cats with clinical signs (P < 0.01) and cats aged ≥ 6 months (P < 0.05). The high rates of ectoparasite infestation in the cats studied constitute a risk for the spread of vector‐borne infections of zoonotic and veterinary importance. 相似文献
19.
《Reports of Practical Oncology and Radiotherapy》2020,25(4):692-697
PurposeThe objective of this study was to assess synthesized effective atomic number (Zeff) values with a new developed tissue characteristic phantom and contrast material of varying iodine concentrations using single-source fast kilovoltage switching dual-energy CT (DECT) scanner.MethodsA newly developed multi energy tissue characterisation CT phantom and an acrylic phantom with various iodine concentrations of were scanned using single-source fast kilovoltage switching DECT (GE-DECT) scanner. The difference between the measured and theoretical values of Zeff were evaluated. Additionally, the difference and coefficient of variation (CV) values of the theoretical and measured values were compared with values obtained with the Canon-DECT scanner that was analysed in our previous study.ResultsThe average Zeff difference in the Multi-energy phantom was within 4.5%. The average difference of the theoretical and measured Zeff values for the acrylic phantom with variation of iodine concentration was within 3.3%. Compared to the results for the single-source Canon-DECT scanner used in our previous study, the average difference and CV of the theoretical and measured Zeff values obtained with the GE-DECT scanner were markedly smaller.ConclusionsThe accuracy of the synthesized Zeff values with GE-DECT had a good agreement with the theoretical Zeff values for the Multi-Energy phantom. The GE-DECT could reduce the noise and the accuracy of the Zeff values than that with Canon-DECT for the varying iodine concentrations of contrast medium.Advances in knowledgeThe accuracy and precision of the Zeff values of the contrast medium with the GE-DECT could be sufficient with human equivalent materials. 相似文献
20.
This investigation deals with the control effects of the insect pathogenic fungus Metarhizium anisopliae var. anisopliae on Daktulosphaira vitifoliae. In pot experiments, the soil surrounding phylloxera-infected grapes was inoculated with barley colonised with M. anisopliae. After thirty-two days, ineight of ten Metarhizium-applied pots nofresh phylloxera infections could be observed.In two of ten plants, a few fresh nodositiessingly occupied with phylloxera or phylloxeraeggs could be found. In all untreated plants,fresh nodosities with either single (two of sixplants) or multiple (four of six plants)occupation with phylloxera could be observed.M. anisopliae could be re-isolated in aconcentration of <1 × 103 CFU g$minus;1 soil dry weight from those pots with phylloxera-infected plants that had been treated with the fungus. The potential role of M. anisopliae in grape phylloxera management is discussed. 相似文献