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1.
Development of yellow mustard (Sinapis alba L.) with superior quality traits (low erucic and linolenic acid contents, and low glucosinolate content) can make this species as a potential oilseed crop. We have recently isolated three inbred lines Y1127, Y514 and Y1035 with low (3.8%), medium (12.3%) and high (20.8%) linolenic acid (C18∶3) content, respectively, in this species. Inheritance studies detected two fatty acid desaturase 3 (FAD3) gene loci controlling the variation of C18∶3 content. QTL mapping revealed that the two FAD3 gene loci responsible for 73.0% and 23.4% of the total variation and were located on the linkage groups Sal02 and Sal10, respectively. The FAD3 gene on Sal02 was referred to as SalFAD3.LA1 and that on Sal10 as SalFAD3.LA2. The dominant and recessive alleles were designated as LA1 and la1 for SalFAD3.LA1, and LA2 and la2 for SalFAD3.LA2. Cloning and alignment of the coding and genomic DNA sequences revealed that the SalFAD3.LA1 and SalFAD3.LA2 genes each contained 8 exons and 7 introns. LA1 had a coding DNA sequence (CDS) of 1143 bp encoding a polypeptide of 380 amino acids, whereas la1 was a loss-of-function allele due to an insertion of 584 bp in exon 3. Both LA2 and la2 had a CDS of 1152 bp encoding a polypeptide of 383 amino acids. Allele-specific markers for LA1, la1, LA2 and la2 co-segregated with the C18∶3 content in the F2 populations and will be useful for improving fatty acid composition through marker assisted selection in yellow mustard breeding.  相似文献   

2.
This study developed a method for estimating the leaf area (LA) of muskmelon by using allometry. The best linear measure was evaluated first, testing both a leaf length and width (W). Leaf samples were collected from plants grown in containers of different sizes, leaves of four cultivars, at different develpoment stages, and of different leaf sizes. Two constants of a power equation were determined for relating allometrically a linear leaf measure and LA, in a greenhouse crop. W proved to be a better fit than the leaf length. The maximum attainable W and LA were estimated at Wx = 15.4 cm and LAx = 174.1 cm2. The indicators of fit quality showed that the function was properly related to LA and W as: LA/LAx = Ao × (W/WLx)b; the allometric exponent was b = 1.89, where R 2 = 0.9809 (n = 484), the absolute sum of squares, 0.4584, and the standard deviation of residues, 0.03084, based on relative values calculations (LA/LA x and W/WLx). The relationship was not affected by the cultivar, crop age, leaf size or stress treatment in the seedling stage. The empirical value of allometric constant (A0) was estimated as 0.963.  相似文献   

3.
4.
The results of three long-term breeding and genetic experiments with Drosophila melanogaster performed at different times are summarized. Selections for different fitness components led to similar results. The data on the concentration of viability mutations in the inbred strains LA, LA+, and LA? after 400 generations of selection and the strain ULA during its breeding are presented for the first time. The results of studying the genetic heterogeneity and spontaneous mutational process in Drosophila inbred strains comply with the idea of M.E. Lobashev that “a change in the direction of selection or acceleration of its rate is always accompanied by a concurrent increase in mutational variation.”  相似文献   

5.
Eucalypt chloroplast DNA (cpDNA) provides useful markers for phylogenetic and population research including gene flow and maternity studies. All cpDNA studies in Eucalyptus to date have been based on the RFLP technique, which requires relatively large amounts of clean DNA. The objective of this study was to develop PCR-based cpDNA markers for Eucalyptus. The chloroplast genome of Eucalyptus, like that of most angiosperms, possesses inverted repeats (IR). The two junctions between the IRs and the large single copy (LSC) regions are defined as JLA andJLB. The region surrounding the JLA junction was sequenced from 26 Eucalyptus DNA samples (21 of E. globulus, plus 5 other species), andtheJLB region was sequenced using 5 of these samples. The samples were chosen to represent all major haplotypes identified in previous cpDNA RFLP studies. The JLA products were 150–210 bp in size, while those fromJLB were approximately 500 bp in size. Eighteen mutations were scored in total. Extensive variation was found in the IR within the intergenic spacer between rpl2 and the IR/LSC junctions. Many of these characters were complex indels. One sample of E. globulus possessed a relatively large (38 bp) insertion which caused displacement of the IR/LSC junctions. This is the first report of intraspecific variation in the position of IR/LSC junctions; interspecific variation was also found. The LSC region near JLB had a low rate of mutation and none were informative. The LSC region near JLA possessed 2 informative mutations. The variation revealed from these sequences reflects the differentiation previously uncovered in an extensive RLFP analysis on the same samples. These results suggest that the JLA region will provide very useful cpDNA polymorphisms for future studies in Eucalyptus. Received: 20 March 1999 / Accepted: 16 December 1999  相似文献   

6.
The influence ofH-2 subregions on graft survival in a liver slice-tokidney bed grafting system has been investigated.H-2K-region andH-2IA-region donor-recipient differences, either individually or in concert, cause acute graft rejection.H-2D-region donor-recipient differences cause chronic immunological reaction as evaluated by histological criteria. Grafts across this barrier may ultimately be rejected or may survive indefinitely. Several possible explanations for the variation in survival are proposed. The remaining knownH-2 regions (IB, IC, S, andG) all appear to cause immunological reactivity in a recipient animal which differs from the liver tissue donor at any of these regions. However, only anIC-region difference may ultimately cause complete graft destruction following an extended chronic immunological course. Grafts across background histocompatibility barriers of several genetic types show rejection patterns equivalent to those seen acrossK andIA barriers. These patterns are unchanged, whether or not the donor and recipient are congenic forH-2 alleles. DifferentH-2 allelic donor-recipient differences do, however, show different times of survival, indicating variation in strength or number of donor antigens or differences in recipient immune response.  相似文献   

7.
Summary In situ hybridization with polytene chromosomes was used to demonstrate the transposition of mobile dispersed genes (mdg)-1 and 3 following the selection of flies from low reproductive activity and vability (LA stock) for high reproductive activity, viability and fitness (LA+ and HA stocks).The inbred LA stock is continuously selected for low reproductive activity and viability and maintains at least for twentyfive generations a characteristic pattern of mdg-1 distribution in 14–15 sites. Inbred LA+ and HA stocks exhibit a changed pattern of mdg-1 locations and the number of sites reaches 21–25. Parallel and independent selection for higher viability may lead to similar characteristic changes in the localization of mdg-1.In several independent experiments we observed, within one generation, a spontaneous and saltatory growth of viability and fitness in the mass-bred LA stock. In these cases new mdg-1 and mdg-3 sites reproducibly appeared to within several bands, some of them characteristic of LA+ and HA stocks.We discuss the possible role of mdg in determining the quantitative characters of individuals and their fitness.  相似文献   

8.

Background

The Glasgow Coma Scale (GCS) is currently the most widely used scoring system for comatose patients. A decade ago, the Full Outline of Unresponsiveness (FOUR) score was devised to better capture four functional aspects of consciousness (eye, motor responses, brainstem reflexes, and respiration). This study aimed to validate the Chinese version of the FOUR score in patients with different levels of consciousness.

Methods

The study had two phases: (1) translation of the FOUR score, and (2) assessment of its reliability and validity. The Chinese version of the FOUR score was developed according to a standardized protocol. One hundred-twenty consecutive patients with acute brain damage, admitted to Nanfang Hospital (Southern Medical University, Guangdong, China) from November 2014 to February 2015, were enrolled. The inter-rater agreement for the FOUR score and GCS was evaluated using intraclass correlation coefficient (ICC). Receiver operating characteristic (ROC) curves were established to determine the scales’ abilities to predict outcome.

Results

The rater agreement was excellent both for FOUR (ICC?=?0.970; p?<?0.001) and GCS (ICC?=?0.958; p?<?0.001). The FOUR score yielded an excellent test-retest reliability (ICC?=?0.930; p?<?0.001). Spearman’s correlation coefficients between GCS and the FOUR score were high: r?=?0.932, first rating; r?=?0.887, second rating (all p?<?0.001). Areas under the curve (AUC) for mortality were 0.834 (95 % CI, 0.740–0.928) and 0.815 (95 % CI, 0.723–0.908) for the FOUR score and GCS, respectively.

Conclusions

The Chinese version of the FOUR score is a reliable scale for evaluating the level of consciousness in patients with acute brain injury.
  相似文献   

9.
The possibility that Ia antigens are unique among H-2 antigens in their relationship to the Fc receptor was investigated in an EA rosette assay. Antibody specific for antigens in various regions of theH-2 complex was incubated with mouse cells, and the ability of the cells to form rosettes with antibody-coated chicken erythrocytes was tested. Antibody raised against the H-2 antigens of Ia-negative tumor cells was highly effective in inhibiting rosette formation. A variety of antisera againstK-, I-, andD-region antigens tested in recombinant mice inhibited EA rosette formation, suggesting that antigens in each of these regions could be detected in rosette inhibition. The F(ab′)2 fragments of all antisera tested also produced specific EA rosette inhibition. Finally, antibody against Ia antigens failed to inhibit bone marrow RFCs, although antibody against H-2K and H-2D antigens did inhibit. Although H-2 serology is in a state of rapid change at present, it must be concluded that in this assay, antibody against antigens in theK andD regions as well as theI region can inhibit EA rosette formation. Inhibition of these rosettes by anti H-2 sera is therefore not due to a special association of Ia antigens with Fc receptors.  相似文献   

10.
Solanum pennellii LA716, a wild relative of tomato, produces acylsugars, an insect resistance compound with activity against many tomato insect pests. Breeding of cultivated tomato using S. pennellii LA716 as a donor parent has led to the development of the elite acylsugar-producing tomato breeding line CU071026. CU071026 contains five introgressed S. pennellii genomic regions, and produces acylsugars at moderate levels that are effective against insect pests. A BC1F1 population was created by crossing the F1 CU071026?×?S. pennellii LA716 with CU071026 as the recurrent parent; this BC1F1 population was used to identify additional regions of the S. pennellii genome important for further improvement of acylsugar production. This population was genotyped with 94 markers in the segregating regions and phenotyped for level of acylsugar production. Using QTLNetwork 2.1 for the detection of quantitative trait loci (QTL) and epistatic interactions, this study identified five QTL for total acylsugar level. Additionally, two epistatic interactions between QTL were found to control significant levels of total acylsugar production. Two of the QTL identified were further evaluated in silverleaf whitefly (Bemisia tabaci) field cage trials using acylsugar breeding lines that differ for the presence/absence of these QTL. While high levels of silverleaf whitefly resistance were observed in all acylsugar breeding lines, lines containing the additional QTL on either chromosomes 6 or 10 had increased levels of total acylsugar production and reduced incidence of whitefly. Acylsugar lines containing the chromosome 6 QTL also had increased density of the type IV glandular trichomes which produce and exude acylsugars.  相似文献   

11.
Probable crossing-over in theB blood group system of chickens   总被引:1,自引:1,他引:0  
Erythrocytes of two chickens from among 1,206 hybrids obtained from a (CB x CC)F1xWB cross reacted with antisera against B antigens of all three lines involved in the cross. The possibility that the two birds had not originated from these crosses was excluded. The irregularity observed in cock 744 is accounted for by assuming a recombinant chromosome, BR1, transmitting part of the B1 and part of the B2 antigenic specificities. Inheritance of B antigens is assumed to be effected by alleles of at least two loci,B-F andB-G. We found that the alleles of theB-F locus determined the serologically defined (SD) and histocompatibility (H) antigens, and the alleles of theB-G locus determined only the SD antigens. The irregularity in theB system of cock 2,349 has not yet been satisfactorily explained.  相似文献   

12.
Estimation of total leaf area (LAT) is important to express biochemical properties in plant ecology and remote sensing studies. A measurement of LAT is easy in broadleaf species, but it remains challenging in coniferous canopies. We proposed a new geometrical model to estimate Norway spruce LAT and compared its accuracy with other five published methods. Further, we assessed variability of the total to projected leaf area conversion factor (CF) within a crown and examined its implications for remotely sensed estimates of leaf chlorophyll content (C ab). We measured morphological and biochemical properties of three most recent needle age classes in three vertical canopy layers of a 30 and 100-year-old spruce stands. Newly introduced geometrical model and the parallelepiped model predicted spruce LAT with an error <5 % of the average needle LAT, whereas two models based on an elliptic approximation of a needle shape underestimated LAT by up to 60 %. The total to projected leaf area conversion factor varied from 2.5 for shaded to 3.9 for sun exposed needles and remained invariant with needle age class and forest stand age. Erroneous estimation of an average crown CF by 0.2 introduced an error of 2–3 μg cm?2 into the crown averaged C ab content. In our study, this error represents 10–15 % of observed crown averaged C ab range (33–53 μg cm?2). Our results demonstrate the importance of accurate LAT estimates for validation of remotely sensed estimates of C ab content in Norway spruce canopies.  相似文献   

13.
14.
Leaf growth responses to N supply and leaf position were studied using widely-spaced sunflower plants growing under field conditions. Both N supply (range 0.25 to 11.25 g added N per plant) and leaf position significantly (p=0.001) affected maximum leaf area (LAmax) of target leaves through variations in leaf expansion rate (LER); effects on duration of expansion were small. Specific leaf nitrogen (SLN, g N m-2) fell quite rapidly during the initial leaf expansion phase (LA < 35% LAmax) but leveled off during the final 65% increase of leaf area. This pattern held across leaf positions and N supply levels. Leaf nitrogen accumulation after 35% LAmax continued up to achievement of LAmax; reductions in the higher SLN characteristic of the initial phase were insufficient to cover the nitrogen requirements for expansion during the final phase. LER in the quasi-linear expansion phase (35 to 100% of LAmax) was strongly associated with SLN above a threshold that varied with leaf position (mean 1.79±0.225 g N m-2). This contrasts with the response of photosynthesis at high irradiance to SLN, which has previously been shown to have a threshold of 0.3 g N m-2; in the present work saturation of photosynthetic rate was evident when SLN reached 1.97 g N m-2. Thus, once the area of a leaf exceeds 35% of LAmax, expansion proceeds provided SLN values are close to the levels required for maximum photosynthesis. However, growth of leaves during the initial expansion phase ensures a minimum production of leaf area even at low N supply levels.  相似文献   

15.
There is a genetic difference in rat hemoglobin (Hb) β-chain structure, with alternate alleles, A and B, at a single locus. This study was designed to find out whether marrow sensitivity due to γ exposure and experimentally induced anemia in age-matched adult rats is entirely strain specific or is a combination of both strain and Hb genotype. Eight strains of inbred and outbred rats comprising AA and BB types were examined. The data indicate that there is a relationship between marrow sensitivity and Hb genotypes in response to erythropoietic stress caused by three techniques.  相似文献   

16.

Background

Apical membrane antigen 1 (AMA1) is a leading candidate vaccine antigen against blood-stage malaria, although to date numerous clinical trials using mainly protein-in-adjuvant vaccines have shown limited success. Here we describe the pre-clinical development and optimization of recombinant human and simian adenoviral (AdHu5 and ChAd63) and orthopoxviral (MVA) vectors encoding transgene inserts for Plasmodium falciparum AMA1 (PfAMA1).

Methodology/Principal Findings

AdHu5-MVA prime-boost vaccination in mice and rabbits using these vectors encoding the 3D7 allele of PfAMA1 induced cellular immune responses as well as high-titer antibodies that showed growth inhibitory activity (GIA) against the homologous but not heterologous parasite strains. In an effort to overcome the issues of PfAMA1 antigenic polymorphism and pre-existing immunity to AdHu5, a simian adenoviral (ChAd63) vector and MVA encoding two alleles of PfAMA1 were developed. This antigen, composed of the 3D7 and FVO alleles of PfAMA1 fused in tandem and with expression driven by a single promoter, was optimized for antigen secretion and transmembrane expression. These bi-allelic PfAMA1 vaccines, when administered to mice and rabbits, demonstrated comparable immunogenicity to the mono-allelic vaccines and purified serum IgG now showed GIA against the two divergent strains of P. falciparum encoded in the vaccine. CD8+ and CD4+ T cell responses against epitopes that were both common and unique to the two alleles of PfAMA1 were also measured in mice.

Conclusions/Significance

Optimized transgene inserts encoding two divergent alleles of the same antigen can be successfully inserted into adeno- and pox-viral vaccine vectors. Adenovirus-MVA immunization leads to the induction of T cell responses common to both alleles, as well as functional antibody responses that are effective against both of the encoded strains of P. falciparum in vitro. These data support the further clinical development of these vaccine candidates in Phase I/IIa clinical trials.  相似文献   

17.
The tomato as both a fresh consumption and industrial product is one of the most profitable vegetables and has a large cultivation area in the world. Parallel to intense production activities, Tomato Spotted Wilt Virus (TSWV), like viral diseases, results in significant economic losses every year. Use of resistant cultivars is the most efficient and environmental-friendly method of fighting against these diseases. This study was conducted to develop new tomato genetic resources resistant to TSWV because of the Sw-5 resistance breaking (RB) isolates that were determined in tomato cultivation areas. In this study, a total of 40 tomato materials including 15 lines, 9 commercial varieties and 16 wild genotypes were by tested with molecular and biological testing methods. Mechanical inoculation method was used for biological testing and SCAR marker was used in molecular analysis. S. penellii, S. chmielewski, S. habrochaites, S. peruvianum and S. sitiens, LA0716, LA1028, LA1777, LA2744 and LA4110 genotypes were found as resistant against breaking isolates of Tomato Spotted Wilt Virus. These genotypes may be a good resistance source for the future breeding studies in tomato.  相似文献   

18.
The extracellular surface of theα-chain ofTorpedo california acetylcholine receptor (AChR) was mapped for regions that are accessible to binding with antibodies against a panel of synthetic overlapping peptides which encompassed the entire extracellular parts of the chain. The binding of the antipeptide antibodies to membrane-bound AChR (mbAChR) and to isolated, soluble AChR. was determined. The specificity of each antiserum was narrowed down by determining the extent of its cross-reaction with the two adjacent peptides that overlap the immunizing peptide. With mbAChR, high antibody reactivity was obtained with antisera against peptidesα1–16,α89–104,α158–174,α262–276, andα388–408. Lower, but significant, levels of reactivity were obtained with antibodies against peptidesα67–82,α78–93,α100–115, andα111–126. On the other hand, free AChR bound high levels of antibodies against peptidesα34–49,α78–93,α134–150,α170–186, andα194–210. It also bound moderate levels of antibodies against peptidesα262–276 andα388–408. Low, yet significant, levels of binding were exhibited by antibodies against peptidesα45–60,α111–126, andα122–138. These binding studies, which enabled a comparison of the accessible regions in mbAChR and free AChR, revealed that the receptor undergoes considerable changes in conformation upon removal from the cell membrane. The exposed regions found here are discussed in relation to the functional sites of AChR (i.e., the acetylcholine binding site, the regions that are recognized by anti-AChR antibodies, T-cells and autoimmune responses and the regions that bind short and long neurotoxins).  相似文献   

19.
20.
《Endocrine practice》2019,25(10):994-1002
Objective: To provide real world observational data about glucose control, the burden of diabetes, comorbidities, and cardiovascular risk factors among patients initiating second-line therapy in Latin America (LA).Methods: This report is a cross-sectional analysis of the LA cohort of the DISCOVER study, describing the regional prevalence of microvascular and macrovascular complications in Mexico, Costa Rica, Panama, Colombia, Argentina, and Brazil.Results: One thousand six hundred and sixteen patients were included in 69 investigational sites. Hemoglobin A1c was >7% (42 mmol/mol) in 81.3% of subjects. Macrovascular complications were reported by 13.8% of the subjects. Microvascular conditions were reported in 15.2% of the subjects. The prevalence of hypertension and of hyperlipidemia was 55.5% and 45.9%, respectively. Blood pressure, total cholesterol, and low-density lipoprotein were out of target levels in 38.5%, 51.2%, and 81.7% of the patients, respectively. Overweight or obesity was reported in 83.8% of the cases.Conclusion: Our study shows that patients with type 2 diabetes in LA are not reaching their glucose, lipids, blood pressure, and weight targets. The prevalence of microvascular (15.2%), macrovascular (13.8%), and uncontrolled comorbidities in patients at an early stage of the disease (initiating a second-line therapy) highlights the need for more aggressive risk factor screening as well as treatment in LA.Abbreviations: CV = cardiovascular; CVD = cardiovascular disease; DM = diabetes mellitus; HbA1c = hemoglobin A1c; LA = Latin America/Latin American; LDL = low density cholesterol; T2DM = type 2 diabetes mellitus  相似文献   

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