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1.
Gróf A 《Magyar onkologia》2007,51(3):197-208
When competing programs ought to be financed simultaneously for the same purpose, an allocation problem occurs due to scarce resources, and different perspectives and preferences. Facing the problem needs determining criteria which the decision might be based on. Those criteria form the objectives (the scope) of the different participants, and are relevant for the achievement of the goal, providing a comprehensive resource allocation that bridges and integrates the different perspectives. In case of cancer control primary prevention, secondary prevention, therapy and tertiary prevention, education, basic sciences, and clinical trials form the alternatives. An analytic hierarchy process (AHP) is used for supporting decision-making in the resource allocation problem. AHP is a method for setting priorities, but can only work out the implications of what was declared through the pairwise-ranking process, namely the relative preferences, weighing the criteria and rating the alternatives two by two. In the first analysis the relative weights to criteria were 0.099 for 'distributive justice'; 0.120 for constitutional and human rights; 0.251 for lay opinion; 0.393 for EBM; 0.137 for cost-effectiveness. Ranking the alternatives using 'judgements' resulted in relative preference of 0.238 for therapy, 0.204 for primary prevention, 0.201 for secondary prevention, 0.135 for clinical trials, 0.111 for tertiary prevention, 0.066 for basic sciences and 0.045 for education. In the second analysis the relative importance of "cost-effectiveness" was doubled, thus resulting in 0.234 for therapy, 0.216 for secondary prevention, 0.183 for primary prevention, 0.145 for clinical trials, 0.113 for tertiary prevention, 0.063 for basic sciences and 0.046 for education. Sensitivity analysis has shown that increasing the relative weight of cost-effectiveness up to approximately 0.4 changes the rank of alternatives, and above 0.4 this criterion gives secondary prevention preferences. According to the relative rates computed in both of the models all criteria vote for therapy, but these preferences change at the high level of weights, in case of EBM, 'rights', and cost-effectiveness. Cost-effectiveness prefers secondary prevention to therapy; the criterion of constitutional and human rights and the criterion of evidence-based medicine vote for primary prevention.  相似文献   

2.
The rate of reaction between alpha-amino groups and cyanic acid was followed at 26 degrees and ionic strength 0.2 M as a function of pH of human hemoglobin Ao solutions to determine the pK and the pH-independent second order rate constant, kappa, for these groups in the alpha and beta chains. At a given point in time, the extent of the reaction was determined by employing the Beckmann Sequencer as a quantitative tool in which the yields of leucine and histidine in the second Edman degradation cycle were used to define the rates of reaction of the alpha and beta chains, respectively. From these results, the individual were evaluated (Garner, M.H., Garner, W.H., and Gurd, F. R.N. (1973) J. Biol. Chem. 248, 5451-5455). Values for pK for the alpha and beta chains were, respectively, 6.74 and 6.93 for cyanoferrihemoglobin, 6.95 and 7.05 for carboxyhemoglobin, and 7.79 and 6.84 for deoxyhemoglobin. Values for kappa, M- minus 1 S-minus 1, for the alpha and beta chains were, respectively, 12.5 and 17 for cyanoferrihemoglobin, 12 and 18 for carboxyhemoglobin, and 91 and 24 for deoxyhemoglobin. Limits of significance were estimated for both variables in each case. The pK results for valine 1alpha agree well with the value obtained by Hill and Davis (1967) J. Biol. Chem. 242, 2005-2012) for carboxyhemoglobin and with that of Kilmartin and Rossi-Bernardi ((1971) Biochem. J. 124, 31-45) for deoxyhemoglobin. Values obtained for sperm whale myoglobin were 7.77 for pK and 7.4 for kappa. The results are useful for the interpretation of the allosteric interactions of hemoglobin with hydrogen ions, with CO2, and with phosphate.  相似文献   

3.
Among the many simultaneous determination methods for carotenoid and retinoid, there are only a few reports including the saponification process. However, the yields of beta-carotene and retinol were higher when using this process. In this study, the analytical conditions, including saponification, were investigated. The extraction solvent was n-hexane and the sample solvent was HPLC mobile phase in the beta-carotene and retinol analysis. BHT as an antioxidant was added at concentrations of 0.125 and 0.025%, respectively, to ethanol and n-hexane phase in the extraction process for serum. The recovery rates were 99.7, 93.7 and 98.3% for beta-carotene, retinol and retinyl palmitate in serum, respectively, and 107.1, 92.8 and 98.8% for beta-carotene, retinol and retinyl palmitate in liver, respectively. The within-day coefficients of variation (C.V.) were 6.0% for serum and 4.7% for liver in the case of beta-carotene, 7.1% for serum, and 5.1% for liver in the case of retinol. The between-day coefficients of variation were 2.7% for serum and 2.7% for liver in the case of beta-carotene, and for retinol, 6.4% for serum and 2.7% for liver.  相似文献   

4.
On the basis of examination of the collection of the Natural History Museum (london), an annotated list of 36 encyrtid species with new records for 12 countries is given: one species new for both Ukraine and Croatia; two, for Austria, Cyprus, and Norway; three, for U.K.; four, for Germany and Spain; five, for Bulgaria; six, for Italy; eight, for France, and twelve, for Greece.  相似文献   

5.
This paper presents a method for constructing a one-sex life table that incorporates age, marriage and parity. The life table is the basis for a generalized population model, with immediate extension to a stable population differentiated by age, marriage and parity status. The method is quite general and could be extended, without major modification, to more complex life tables.Computation of intrinsic rates of increase for a number of populations adjusted for age, for age and parity, for age and marriage, and for age, marriage and parity shows that adjustment for marriage accounts for most of the difference between the age-adjusted rate and the age-, marriage-, and parity-adjusted rate. Adjustment for parity without adjustment for marriage may be misleading.  相似文献   

6.
Aspects related to hatching, life time, mortality, feeding behaviour and fecundity for each stage of Triatoma pallidipennis life-cycle were evaluated. The hatching rate observed for 200 eggs was 60% and the average time of hatching was 18 days. Eighty nymphs (N) (40%) completed the cycle and the average time from NI to adult was 168. 7+/-11.7days. The average span in days for each stage was 18.0 for NI, 18.5 for NII, 30.0 for NIII, 35.7 for NIV and 50.1 for NV. The number of bloodmeals at each nymphal stage varied from 1 to 5. The mortality rate was 9.17 for NI, 5.5 for NII, 6.8 for NIII 4.17 for NIV and 13.04 for NV nymphs. The average number of eggs laid per female in a 9-month period was 498.6. The survival rates of adults were 357+/-217.9 and 262.53+/-167.7 for males and females respectively.  相似文献   

7.
A total of 1922 first generation crossbred cows born between 2005 and 2012 produced by inseminating purebred Israeli Holstein cows with Norwegian Red semen, and 7487 purebred Israeli Holstein cows of the same age in the same 50 herds were analyzed for production, calving traits, fertility, calving diseases, body condition score, abortion rate and survival under intensive commercial management conditions. Holstein cows were higher than crossbreds for 305-day milk, fat and protein production. Differences were 764, 1244, 1231 for kg milk; 23.4, 37.4, 35.6 for kg fat, and 16.7, 29.8, 29.8 for kg protein; for parities 1 through 3. Differences for fat concentration were not significant; while crossbred cows were higher for protein concentration by 0.06% to 0.08%. Differences for somatic cells counts were not significant. Milk production persistency was higher for Holstein cows by 5, 8.3 and 8% in parities 1 through 3. Crossbred cows were higher for conception status by 3.1, 3.6 and 4.7% in parities 1 through 3. Rates of metritis for Holsteins were higher than the crossbred cows by 7.8, 4.6 and 3.4% in parities 1 to 3. Differences for incidence of abortion, dystocia, ketosis and milk fever were not significant. Holstein cows were lower than crossbred cows for body condition score for all three parities, with differences of 0.2 to 0.4 units. Contrary to comparisons in other countries, herd-life was higher for Holsteins by 79 days. A total of 6321 Holstein cows born between 2007 and 2011 were higher than 765 progeny of crossbred cows backcrossed to Israeli Holsteins of the same ages for milk, fat and protein production. Differences were 279, 537, 542 kg milk; 10.5, 17.7, 17.0 kg fat and 6.2, 12.9, 13.2 kg protein for parities 1 through 3. Differences for fat concentration were not significant, while backcross cows were higher for protein percentage by 0.02% to 0.04%. The differences for somatic cell score, conception rate, and calving diseases other than metritis, were not significant. Holstein cows were lower than backcross cows by 1.5% to 2.5% for conception status in parities 1 to 3 and lower for body condition score for parities 1 and 2, with differences in the range of 0.06 to 0.09 units. Culling rates were higher, and herd-life lower for the crossbred cows. The gains obtained in secondary traits for crossbred cows did not compensate for the major reduction in production.  相似文献   

8.
The current paper is a synoptic review of the distribution and host associations of the 25 species of hard tick fauna (family Ixodidae) in Romania. In addition to a full literature survey, original data is presented, based on eight years of occasional or targeted sample collection. The literature data on geographical distribution was transposed digitally to the decimal degree coordinate system. For each species, an updated distribution map is given together with all historical data and new host associations. Overall, our paper records 58 new tick-host associations for Romania: 20 for Ixodes ricinus, 1 for I. apronophorus, 6 for I. arboricola, 2 for I. hexagonus, 9 for I. redikorzevi, 1 for I. trianguliceps, 2 for I. vespertilionis, 2 for Haemaphysalis punctata, 1 for H. sulcata, 2 for H. concinna, 1 for D. marginatus, 4 for Rhipicephalus sanguineus sensu lato, 1 for R. bursa and 6 for Hyalomma marginatum.  相似文献   

9.

Purpose

This study aimed to establish a set of disability weights (DWs) for sleep problems and fatigue which could be applied in composite health outcome measures in order to quantify the burden of symptoms and economically evaluate the effects of increasing temperatures on a life cycle approach.

Methods

The conditions were evaluated by a two-step questionnaire study. In the first step, specialists determined the DW for each condition. The second step was identical to the first, except that the determinations were made by primary care physicians. Both groups of medical practitioners used an interpolation method consisting of a comprehensive set of 31 disease-specific DWs.

Results and discussion

Mean DWs for sleep disturbance were 0.101 for environmental sleep disturbance, 0.069 for mild sleep disturbance, and 0.086 for moderate sleep disturbance. Mean DWs for chronic fatigue syndrome (CFS) were 0.099 for a diagnosis of CFS, 0.164 for mild handicap, 0.281 for moderate handicap, and 0.459 for severe handicap. Mean DWs assigned by primary care physicians for sleep disturbance were 0.114 for environmental sleep disturbance, 0.140 for mild sleep disturbance, and 0.126 for severe sleep disturbance. Those for CFS were 0.154 for a diagnosis, 0.099 for mild handicap, 0.147 for moderate handicap, and 0.226 for severe handicap.

Conclusions

Using the present valuation protocol, it appeared feasible to establish the burden of symptoms as attributable to increasing temperatures. The results can be applied in composite health outcome measures for public health research, environmental research, and economic evaluations.  相似文献   

10.
Soil salinity and alkalinity are important abiotic components that frequently have critical effects on crop growth, productivity and quality. Developing soybean cultivars with high salt tolerance is recognized as an efficient way to maintain sustainable soybean production in a salt stress environment. However, the genetic mechanism of the tolerance must first be elucidated. In this study, 257 soybean cultivars with 135 SSR markers were used to perform epistatic association mapping for salt tolerance. Tolerance was evaluated by assessing the main root length (RL), the fresh and dry weights of roots (FWR and DWR), the biomass of seedlings (BS) and the length of hypocotyls (LH) of healthy seedlings after treatments with control, 100 mM NaCl or 10 mM Na2CO3 solutions for approximately one week under greenhouse conditions. A total of 83 QTL-by-environment (QE) interactions for salt tolerance index were detected: 24 for LR, 12 for FWR, 11 for DWR, 15 for LH and 21 for BS, as well as one epistatic QTL for FWR. Furthermore, 86 QE interactions for alkaline tolerance index were found: 17 for LR, 16 for FWR, 17 for DWR, 18 for LH and 18 for BS. A total of 77 QE interactions for the original trait indicator were detected: 17 for LR, 14 for FWR, 4 for DWR, 21 for LH and 21 for BS, as well as 3 epistatic QTL for BS. Small-effect QTL were frequently observed. Several soybean genes with homology to Arabidopsis thaliana and soybean salt tolerance genes were found in close proximity to the above QTL. Using the novel alleles of the QTL detected above, some elite parental combinations were designed, although these QTL need to be further confirmed. The above results provide a valuable foundation for fine mapping, cloning and molecular breeding by design for soybean alkaline and salt tolerance.  相似文献   

11.
Teak (Tectona grandis Linn. f.) has been planted extensively in the tropics for its highly valued timber. We analysed data from a 3.5-year-old teak progeny test with clonal replication located in northern Australia. Additive and non-additive genetic variances were estimated for commercially important traits. Trees originating from seedlings were on average 2% taller and 4% straighter than those of the same genotype originating from cuttings. Non-additive genetic variance represented 35–50% of total genetic variance for growth traits and 63% of total genetic variance for incidence of flowering. Narrow-sense heritability was 0.22 for diameter, 0.18 for height and volume, 0.07 for stem straightness, 0.05 for insect defoliation, 0.03 for epicormic sprouts and 0.30 for incidence of flowering (estimated on an assumed underlying continuous scale). Broad-sense heritability was 0.37 for diameter, 0.28 for height, 0.35 for volume, 0.12 for stem straightness, 0.06 for insect defoliation, 0.12 for epicormic sprouts and 0.71 for incidence of flowering. Positive correlations were found between tree volume and flowering and between tree volume and stem straightness. The presence of sizeable non-additive variance supports the selection and deployment of clones to capture the full extent of genetic variation in commercially important traits.  相似文献   

12.
The aim of this study was to estimate the genetic parameters for preweaning traits and their relationship with reproductive, productive and morphological traits in alpacas. The data were collected from 2001 to 2015 in the Pacomarca experimental farm. The data set contained data from 4330 females and 3788 males corresponding to 6396 and 1722 animals for Huacaya and Suri variants, respectively. The number of records for Huacaya and Suri variants were 5494 and 1461 for birth weight (BW), 5429 and 1431 for birth withers height (BH), 3320 and 896 for both weaning weight (WW) and average daily gain (DG) from birth to weaning, 3317 and 896 for weaning withers height (WH), and 5514 and 1474 for survival to weaning. The reproductive traits analyzed were age at first calving and calving interval. The fiber traits were fiber diameter (FD), standard deviation of FD (SD), comfort factor and coefficient of variation of FD and the morphological traits studied were density, crimp in Huacaya and lock structure in Suri, head, coverage and balance. Regarding preweaning traits, model of analysis included additive, maternal and residual random effects for all traits, with sex, coat color, number of calving, month–year and contemporary group as systematic effects, and age at weaning as linear covariate for WW and WH. The most relevant direct heritabilities for Huacaya and Suri were 0.50 and 0.34 for WW, 0.36 and 0.66 for WH, 0.45 and 0.20 for DG, respectively. Maternal heritabilities were 0.25 and 0.38 for BW, 0.18 and 0.32 for BH, 0.29 and 0.39 for WW, 0.19 and 0.26 for WH, 0.27 and 0.36 for DG, respectively. Direct genetic correlations within preweaning traits were high and favorable and lower between direct and maternal genetic effects. The genetic correlations of preweaning traits with fiber traits were moderate and unfavorable. With morphological traits they were high and positive for Suri but not for Huacaya and favorable for direct genetic effect but unfavorable for maternal genetic effect with reproductive traits. If the selection objective was meat production, the selection would have to be based on the direct genetic effect for WW but not on the maternal genetic effect that has been shown to have less relevance. Other weaning traits such as WH or DG would be indirectly selected.  相似文献   

13.
Oxidation-reduction midpoint potentials were determined, as a function of pH, for the disulfide/dithiol couples of spinach and pea thioredoxins f, for spinach and Chlamydomonas reinhardtii thioredoxins m, for spinach ferredoxin:thioredoxin reductase (FTR), and for two enzymes regulated by thioredoxin f, spinach phosphoribulokinase (PRK) and the fructose-1,6-bisphosphatases (FBPase) from pea and spinach. Midpoint oxidation-reduction potential (Em) values at pH 7.0 of -290 mV for both spinach and pea thioredoxin f, -300 mV for both C. reinhardtii and spinach thioredoxin m, -320 mV for spinach FTR, -290 mV for spinach PRK, -315 mV for pea FBPase, and -330 mV for spinach FBPase were obtained. With the exception of spinach FBPase, titrations showed a single two-electron component at all pH values tested. Spinach FBPase exhibited a more complicated behavior, with a single two-electron component being observed at pH values >/= 7.0, but with two components being present at pH values <7.0. The slopes of plots of Em versus pH were close to the -60 mV/pH unit value expected for a process that involves the uptake of two protons per two electrons (i. e., the reduction of a disulfide to two fully protonated thiols) for thioredoxins f and m, for FTR, and for pea FBPase. The slope of the Em versus pH profile for PRK shows three regions, consistent with the presence of pKa values for the two regulatory cysteines in the region between pH 7.5 and 9.0.  相似文献   

14.
The rearing of Galleria mellonella L. in laboratory is important for multiplication of entomopathogenic nematodes, mandatory for biological control studies. The objective of this study was to evaluate the effect of three thermal profiles on development stages of this insect, allowing synchronization of cycle production. Two distinct rearing phases were done: firstly, using nucleous of incubation for development of eggs and, secondly, using circular-aluminum manifolds for development of larvae and pupae. The time necessary for development of the immature stages decreased with higher temperatures. Incubation periods lasted 13.4 days at 22 degrees C, 8.3 at 27 degrees C and 6.8 days at 32 degrees C, while periods for larvae development lasted 40.4, 27.2, and 23.4 days, respectively, for the same temperatures. Development to pupal stage was observed 18.2, 15.0, and 12.2 days, respectively, for the same temperatures. Larval survival was higher at 32 degrees C, however embryonic stages and pupae survival were higher at 27 degrees C. and 22 degrees C, respectively. The threshold temperature was 11.209167 degrees C for the embryonic development stage, 7.695869 degrees C for larval stage, and 1.943050 degrees C for pupal stage of G. mellonella. Thermal constants were 138.380533 DG (degree day) for egg, 554.968830 DG for larvae, and 369.054080 DG for pupae.  相似文献   

15.
Genetic parameters for growth, mortality and reproductive performances of Markhoz goats were estimated from data collected during 1993–2010 at Markhoz goat Performance Testing Station in Sanandaj, Iran. For kid performance traits 3763 records were available for birth weight (BW), 2931 for weaning weight (WW), average daily gain (ADG) and Kleiber ratio (KR) (approximated as ADW/WW0.75) and 3032 for pre-weaning mortality (PWM). For doe reproductive performance traits there were 2920 records available for litter size at birth (LSB), litter size at weaning (LSW), total litter weight at birth (TLWB) and litter mean weight per kid born (LMWKB), and 2182 for total litter weight at weaned (TLWW) and litter mean weight per kid weaned (LMWKW). Genetic parameters were estimated with univariate and bivariate models using restricted maximum likelihood (REML) procedures. Random effects were explored by fitting additive direct genetic effects, maternal additive genetic effects, maternal permanent environmental effects, the covariance between direct and maternal genetic effects, and common litter effects in different models for pre-weaning traits of kids. Also, in addition to an animal model, sire and threshold models, using a logit link function, were used for analyses of PWM. Models for LSB, LSW, TLWB, TLWW, LMWKB, and LMWKW included direct additive genetic effects, permanent environmental effects due to the animal as well as service sire effects. Estimated direct heritabilities were moderate for pre-weaning traits (0.22 for BW, 0.16 for WW, 0.21 for ADG, and 0.27 for KR and 0.29 for PWM), and low for reproduction traits (0.01 for LSB, 0.01 for LSW, 0.02 for TLWB, 0.03 for TLWW, 0.07 for LMWKB, and 0.06 for LMWKW). The estimates for the maternal additive genetic variance ratios were lower than direct heritability for BW (0.07) and KR (0.04). The estimate for the maternal permanent environmental variance ratios (c2) varied from 0.01 for KR to 0.07 for WW and ADG. The magnitude of common litter variance ratios (l2) was more substantial for BW (0.46) than the PWM (0.19) and KR (0.16). The estimate for the permanent environmental variance due to the animal (c2) ranged from 0.03 for LMWKB to 0.07 for TLWB and LMWKW, whereas service sire effects (s2) ranged from 0.02 to 0.04. The correlation between direct and maternal genetic effects were negative and high for BW (?0.51) and KR (?0.62). The genetic correlations between pre-weaning growth traits were positive and moderate to strong, as were genetic correlations between reproductive traits. Between BW and PWM the correlation was ?0.35. Phenotypic and environmental correlations for all traits were generally lower than genetic correlations.  相似文献   

16.
Performance of dairy cattle clones and evaluation of their milk composition   总被引:2,自引:0,他引:2  
Genetic and phenotypic performance of U.S. Holstein embryo-split and nuclear-transfer clones was documented for yield and fitness traits. For cows, mean genetic superiority based on pedigree was 186 kg of milk, 9 kg of fat, and 7 kg of protein for embryo-split clones and 165, 10, and 8 kg, respectively, for nuclear-transfer clones compared with the population for the same birth year; pedigree advantage for male clones generally was slightly greater. Estimates of genetic merit that considered a clone's own performance as well as pedigree merit were slightly lower for embryo-split cows than for their full siblings for yield but not for milk composition (fat and protein percentages), mastitis resistance (somatic cell score), longevity (productive life), or cow fertility (daughter pregnancy rate); no corresponding genetic differences were found for nuclear-transfer cows or for cloned bulls regardless of clone type. For bulls, estimated genetic merit based on daughter yield was more similar for clone pairs with apparent identical genotype than for pairs from the same biotechnology but nonidentical as confirmed by blood typing. Yield deviations were lower for clones than for their full siblings. Milk composition (total solids, fat, fatty acid profile, lactose, and protein) also was compared for nuclear-transfer clones (Brown Swiss, Holstein, and Holstein-Jersey cross) with non-cloned cows and literature values; no differences were found for gross chemical composition of milk. No obvious differences were evident between cloned and non-cloned animals or for the milk that they produced.  相似文献   

17.
Drought tolerance is one of the most important but complex traits of crops. We looked for quantitative trait loci (QTLs) that affect drought tolerance in maize. Two maize inbreds and their advanced lines were evaluated for drought-related traits. A genetic linkage map developed using RFLP markers was used to identify QTLs associated with drought-related traits. Twenty-two QTLs were detected, with a minimum of one and a maximum of nine for drought-related traits. A single-QTL was detected for sugar concentration accounting for about 52.2% of the phenotypic variation on chromosome 6. A single-QTL was also identified for each of the traits root density, root dry weight, total biomass, relative water content, and leaf abscisic acid content, on chromosomes 1 and 7, contributing to 24, 0.2, 0.4, 7, and 19% of the phenotypic variance, respectively. Three QTLs were identified for grain yield on chromosomes 1, 5, and 9, explaining 75% of the observed phenotypic variability, whereas four QTLs were detected for osmotic potential on chromosomes 1, 3, and 9, together accounting for 50% of the phenotypic variance. Nine QTLs were detected for leaf surface area on chromosomes 3 and 9, with various degrees of phenotypic variance, ranging from 25.8 to 42.2%. Four major clusters of QTLs were identified on chromosomes 1, 3, 7, and 9. A QTL for yield on chromosome 1 was found co-locating with the QTLs for root traits, total biomass, and osmotic potential in a region of about 15 cM. A cluster of QTLs for leaf surface area were coincident with a QTL for osmotic potential on chromosome 3. The QTLs for leaf area also clustered on chromosome 9, whereas QTLs for leaf abscisic acid content and relative water content coincided on chromosome 7, 10 cM apart. Co-location of QTLs for different traits indicates potential pleiotropism or tight linkage, which may be useful for indirect selection in maize improvement for drought tolerance.  相似文献   

18.
目的:利用HPLC-MS/MS方法对十种一碳代谢相关产物进行定量分析。方法:采用Aglient ZORBAX SB-AQ C18柱(2.1mm×100 mm,3.5 m)、电喷雾离子源(ESI),以多离子反应监测方式(MRM)进行正离子检测。对游离叶酸(FA)、5-甲酰四氢叶酸(5-FT)、5-甲基四氢叶酸(5-MT)、S-腺苷蛋氨酸(SAM)、S-腺苷同型半胱氨酸(SAH)、胱硫醚(CYSTA)、组氨酸(HIS)、丝氨酸(SER)、蛋氨酸(MET)、同型半胱氨酸(HCY)进行定量分析。结果:FA、5-FT、5-MT、SAM、SAH、CYSTA、HIS、SER、MET、HCY的检测限分别为0.1 ng.L-1、0.25 ng.L-1、0.1 ng.L-1、0.1 ng.L-1、0.25 ng.L-1、0.25 ng.L-1、0.1 ng.L-1、0.025 ng.L-1、0.1 ng.L-1、0.1 ng.L-1。FA、5-FT、5-MT、SAH、CYSTA浓度测定方法线性范围为2~50 ng.L-1,SER、SAM浓度测定方法线性范围20~500 ng.L-1,MET、HCY浓度测定方法线性范围200~5000 ng.L-1,HIS浓度测定方法线性范围为400~10000 ng.L-1,r均在0.993以上,全部涵盖了已报道的血清中指标的含量范围。结论:建立了HPLC-MS/MS方法,可同时分析十种一碳代谢通路的关键产物,所需样品量少,检测速度快,同时实现分项检测,可为多种代谢性疾病系统性地检测一碳代谢中间产物体液分析方法建立实验条件基础。  相似文献   

19.
Derivatives of D-luciferin, D-luciferin methyl ester, D-luciferin O-sulfate, D-luciferin O-phosphate, D-luciferyl-L-N alpha-arginine and D-luciferyl-L-phenylalanine were used as highly sensitive substrates for carboxylic esterase, arylsulfatase, alkaline phosphatase and carboxypeptidases A, B and N. Enzymatic cleavage of the compounds by enzymes leading to the release of D-luciferin was demonstrated. Kinetic constants have been determined for D-luciferin methyl ester and carboxylic esterase, for D-luciferin O-sulfate and arylsulfatase, for D-luciferin O-phosphate and alkaline phosphatase, for D-luciferyl-L-phenylalanine and carboxypeptidase A, and for carboxypeptidases B and N and D-luciferyl-L-N alpha-arginine. All compounds proved to be highly sensitive substrates for the respective enzymes, permitting a limit of detection for enzymes between 10 and 500 fg per assay.  相似文献   

20.
关于植物DNA条形码研究技术规范   总被引:4,自引:0,他引:4  
DNA条形码是利用标准的基因片段对物种进行快速鉴定的技术,已经成功用于生物物种分类和鉴定、生态学调查和生物多样性评估等研究领域。尽管生命条形码数据(BOLD)系统提供了主要针对动物类群DNA条形码研究的技术规范,但由于植物本身的生物学特性与所使用的条形码不同,因此已有技术规范并不完全适用于植物DNA条形码的研究。本文根据植物DNA条形码研究的特点与我国的实际情况,编写了植物DNA条形码研究技术标准和规范指南,具体包括十个方面的内容,即植物DNA条形码研究的样品采集策略;植物标本和野外数据的采集规范;植物标本图像信息的采集规范;植物DNA材料的采集规范;植物DNA材料的干燥与保存规范;植物总DNA的质量标准及保存规范;植物标准DNA条形码的选择与通用引物;DNA条形码的扩增与测序;DNA条形码数据的命名、编辑和提交规范;以及DNA条形码数据分析。我们期望通过这些标准规范的实施和在实践中的不断修订和完善,能为我国学者开展植物DNA条形码和iFlora研究提供参考和借鉴。
关键词:植物DNA条形码;技术规范;物种鉴定;标准;新一代植物志  相似文献   

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