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1.
Objective： To investigate the association of Graves＇ disease and Graves＇ ophthalmopathy with the C/T transition polymorphism at position -318 of promoter and the A/G transition polymorphism at position 49 of exon 1 within cytotoxic T lymphocyte associated antigen-4 （CTLA-4） gene. Methods： Thirty-three patients with ophthalmopathy of Graves＇ disease, fifty-six Graves＇ patients without ophthalmopathy and sixty normal subjects as control were involved in the present case-control study. The polymorphisms were evaluated by polymerase chain reaction fragment length polymorphism （PCR-RFLP）. Comparisons were made of gene frequencies and allele frequencies between the groups. Results： The gene frequencies of CT and allele frequencies of T were much higher in Graves＇ patients with ophthalmopathy than that in the group without ophthalmopathy （P=-0.020, P=-0.019）. The gene frequencies of GG and allele frequencies of G in patients with Graves＇ disease were significantly increased as compared with control group （P=0.008, P=0.007）. The data suggest that smokers with Graves＇ disease seemed to be more predisposed to ophthalmopathy than non-smokers （P=0.018）. Conclusion： Our results suggest that an allele of T at position -318 of promoter is associated with genetic susceptibility to Graves＇ ophthalmopathy while an allele of G at position 49 of exon 1 is associated with genetic susceptibility to Graves＇ disease instead. Smoking is believed to be a major risk factor for ophthalmopathy.  相似文献   

2.
INTRODUCTION Throughout this paper, we shall work with a filtered complete probability space (?,F,(Ft),P) sat-isfying the usual conditions. Let B=(Bt)t≥0 be a stan-dard Brownian motion with B0=0. Denote by ú the set of all non-negative real numbers. Recall that a diffusion process X starting at x≥0 is called the square of a Bessel process of dimension δ>0 if d X t = δd t 2 | X t |d Bt , X 0= x, (1) Clearly, this equation has a unique non-negative strong solution X, i.e., …  相似文献   

3.
Seed vigor is an important characteristic of seed quality, and rice cultivars with strong seed vigor are desirable in direct-sowing rice production for optimum stand establishment. In the present study, the quantitative trait loci (QTLs) of three traits for rice seed vigor during the germination stage, including germination rate, final germination percentage, and germination index, were investigated using one recombinant inbred line (RIL) population derived from a cross between japonica Daguandao and indica IR28, and using the multiple interval mapping (MIM) approach. The results show that indica rice presented stronger seed vigor during the germination stage than japonica rice. A total of ten QTLs, and at least five novel alleles, were detected to control rice seed vigor, and the amount of variation (R 2) explained by an individual QTL ranged from 7.5% to 68.5%, with three major QTLs with R 2>20%. Most of the QTLs detected here are likely to coincide with QTLs for seed weight, seed size, or seed dormancy, suggesting that the rice seed vigor might be correlated with seed weight, seed size, and seed dormancy. At least five QTLs are novel alleles with no previous reports of seed vigor genes in rice, and those major or minor QTLs could be used to significantly improve the seed vigor by marker-assisted selection (MAS) in rice.  相似文献   

4.
A rice mutant with Yaponica 9522 cultivar background Oryza sativa extraordinary glume 1 （Oseg 1） was identified from the M2 mutant pool mutagenized by ^60Co γ-ray. Compared with wild type plants, Oseg 1 developed longer empty glumes and rudimentary glumes. In some Oseg 1 mutants, the number of stamens of flowers was reduced and leaf-like lodicules occurred, and excessive lemma/palea-like organ could be observed in some mutant spikelets. This indicated that OsEG1 could regulate the development of rudimentary glumes, empty glumes, lemma/palea, lodicules, and stamens. Genetic analysis indicated that Oseg 1 came from a single recessive genetic locus. To clone OsEG1 gene, F2 population was constructed by a cross between Oseg 1 （Japonica） and Guangluai4 （Indica）. Using map-based cloning approach, OsEG1 was mapped on chromosome 4, between INDEL marker OS407 and WHM0466 with genetic distance of 2.0 cm and 1.0 cm, respectively. These results are useful for further cloning and functional analysis of the OsEG1 gene.  相似文献   

5.
This work investigated the microwave dielectric properties of A-site substitution by rare earth La3+in(Pb0.5Ca0.5)(Fe0.5Ta0.5)O3(PCFT) system.A single perovskite phase was obtained only when the doping content was 2%.Suitable La3+ doping improved microwave dielectric performances.Excessive La3+doping caused the formation of secondary phase,which resulted in the decreasing of permittivity εrand quality factor Qfvalues.Especially,when the doping content is 2%-5%,permittivity εrwas above 75 and Qfvalues were 6...  相似文献   

6.

Objective  

The gene for mast cell chymase (CMA1) is an ideal candidate for investigating the genetic predisposition to coronary heart disease (CHD), as activated mast cells have been found to be present in a greater proportion in the shoulder region of atheroma than in normal coronary intimae. Previous studies have indicated that CMA1 promoter polymorphism rs1800875 may be involved in regulating immunoglobulin E (IgE) levels in patients with eczema, and it is associated with the progression of immunoglobulin A nephropathy.  相似文献   

7.
The line persistence of a graph G, Pt （ G ） is the minimum number of lines which must be removed to increase the diameter of G. In Ref. [7] （J. Shanghai Univ., 2003,7（4）：352-357）, we gave a characterization of graphs of diameter five with ρ1 （ G ）≥2. In this paper we will show that each of the 8 special graphs Xi （ i = 1,2,3,4,5,6,7,8） listed in condition （2） of Theorem 1 in Ref. [7] can not be deleted. Therefore the results we obtained in Ref. [7] can not in general be improved.  相似文献   

8.
Postherpetic neuralgia (PHN) is a severe sequela of herpes zoster (HZ). Until now, only age and pain severity were considered predisposing factors for the development of PHN. We evaluated 49 patients with acute phase HZ, 10 of whom developed PHN (Group A) and 39 of whom did not develop PHN (Group B). Twenty-five healthy volunteers similar in age and gender distribution to the study group were recruited as controls (Group C). Numbers of serum CD3+ (pan-T lymphocytes), CD4+ (helper/inducer), and CD8+ (suppressor/cytotoxic) lymphocytes were decreased significantly in Groups A and B relative to the control group, but there were no statistical differences between Groups A and B. Interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, IL-8, and IL-10 were significantly elevated in Groups A and B relative to Group C. IL-6 was significantly higher in Group A than in Group B, and was significantly positively correlated with pain severity scored on a visual analog scale. Therefore, we suggest that the inflammatory response, especially that of IL-6, in the acute phase of HZ may be associated with hyperalgesia and the development of PHN. Project (No. 2008ZYC07) supported by the Zhejiang Medical Bureau of China  相似文献   

9.
Objective: To investigate the cytokine response pattern (IL-4/IFN-γ) in infants with RSV infections and bronchiolitis during the acute phase. Methods: Four-color flow cytometry was used to measure intracellular IL-4 and IFN-γ expressions in peripheral blood CD3+ and CD8+ lymphocytes from RSV-infected and bronchiolitis infants. Serum IL-4 and IFN-γ levels were also determined. Results: RSV-infected and bronchiolitis infants showed no statistical differences from not-RSV-infected or pneumonia infants and control in the frequency of IL-4 and IFN-γ expressions in CD3+CD8- lymphocytes, showed no obvious Th1/Th2 imbalance, while IFN-γ was expressed much more frequently in CD3+CD8+ lymphocytes. Systematically, RSV-infected and bronchiolitis infants showed much lower levels of serum IL-4 and IL-4/IFN-γ ratios and much higher serum IFN-γ levels than control. However, there were no statistical differences in the above three indices between RSV-infected and not-RSV infected infants or between bronchiolitis and pneumonia infants, except that bronchiolitis infants had a higher level of serum IFN-γ than pneumonia infants statistically. Conclusions: There is no type-2 cytokine response predominance in the acute phase of RSV infection and bronchiolitis. IL-4 production is suppressed and IFN-γ production upregulated, the latter being most prominent in bronchiolitis infants.  相似文献   

10.
Background: Allogeneic blood transfusion-induced immunomodulation (TRIM) and its adverse effect on the prognosis of patients treated surgically for cancer remain complex and controversial. However, the potential risk associated with allogeneic blood transfusion has heightened interest in the use of autologous blood transfusion. In the present study, the serum concentrations of neopterin, interferon-gamma (IFN-γ), T lymphocyte subsets (CD3 , CD4 , CD8 , CD4 /CD8 ) and a possible association between these variables were investigated. The purpose was to further evaluate the effect of autologous versus allogeneic blood transfusion on immunological status in patients undergoing surgery for gastric cancer. Methods: Sixty ASA I～II (American Society of Anesthesiologists) patients undergoing elective radical resection for stomach cancer were randomly allocated to receive either allogeneic blood transfusion (n=30) or autologous blood transfusion (n=30). Serum concentrations of the neopterin, IFN-γ and T lymphocyte subsets in the recipients were measured before induction of anesthesia, after operation, and on the 5th postoperative day. Results: Both two groups, serum neopterin, IFN-γ, percentages of T-cell subsets (CD3 , CD4 ), and CD4 /CD8 ratio had significantly decreased after operation, but decreased more significantly in group H (receiving allogeneic blood transfusion) than those in group A (receiving autologous whole blood transfusion) (P<0.05). On the 5th postoperative day, serum neopterin, IFN-γ, CD3 , CD4 T-cells, and CD4 /CD8 ratio returned to the baseline values in group A. In contrast, the above remain decreasing in group H, where there were no significant relations between serum neopterin and IFN-γ. Conclusion: Perioperative surgical trauma and stress have an immunosuppressive impact on gastric cancer patients. Allogeneic blood transfusion exacerbates the impaired immune response. Autologous blood transfusion might be significantly beneficial for immune-compromised patients in the perioperative period, clearly showing its superiority over allogeneic blood transfusion.  相似文献   

11.
Objectives: During visual stimulation, the elevated metabolism rate will couple with increase of blood flow velocity(BFV) in posterior cerebral artery(PCA). This study with TCD was aimed to investigate whether the coupling might change according to the different vasoneuronal conditions. Methods: Ninety-nine volunteers including 24 hypertension(HT) patients and 2 patients suffering from both HT and diabetes mellitus(DM) were enrolled in this trial. BFV and pulse indexes(PI) in P2 segments of PCA on both sides were monitored during visual stimulation. Results: In all subjects, Mean BFV increased and PI went down in response to visual stimulation. The percentages of changes (ΔV and ΔP) of both mean BFV and PI were larger in young group(<55 years old) than in old one(≥55 years old). There was significant positive correlation between ΔV and ΔP. Multivariated regression analysis did not show HT and DM, but age related to ΔV(ΔP). We did not find significant difference of ΔV(ΔP) between left and right sides. Conclusions: Blood flow velocity in PCA P2 segment increased due to decreased cerebrovascular resistance during visual stimulation and the response weakened with aging of the patient.  相似文献   

12.
R. Jayaraman 《Resonance》2008,13(10):898-908
One of the goals of genetics is to understand genes in as much detail as possible. For instance, with respect to a given gene, one would like to know its chromosomal location, its physical and genetic size, its neighbours, the number of mutations/alleles defining the gene, the order of mutations, the genetic/physical distance between them, etc. Thus, rather than focusing on the whole genome, one focuses on the finer details of a given genetic segment. The exercise of probing such details is called ‘fine structure genetic analysis’. There are several pioneers who have contributed enormously to this area in many bacterial and phage systems. Two stalwarts, Seymour Benzer and Charles Yanofsky, stand preeminent among them. In the following pages I present briefly Benzer’s outstanding work on the fine structure of the rII region of bacteriopage T4. These path-breaking studies contributed significantly to our understanding of the structure, organization and function of genes. R Jayaraman is an Emeritus Professor of Molecular Biology at the School of Biological Sciences, Madurai Kamaraj University, Madurai, where he taught and carried out research in the area of microbial genetics for three decades.  相似文献   

13.
1 Introduction We consider the finite digraphs that do not havemultiple arcs or loops , but pairs of opposite arcs areallowed.LetD=(V,A) be a digraph , whereVisthe set of vertices andAis the set of arcs .If there isan arc (x,y) fromxtoy,thenthe vertexxis …  相似文献   

14.
The effectiveness of various analytical formulas for estimating R 2 shrinkage in multiple regression analysis was investigated. Two categories of formulas were identified: estimators of the squared population multiple correlation coefficient (ρ2) and those of the squared population cross-validity coefficient (ρc 2). The authors conducted a Monte Carlo experiment to investigate the effectiveness of the analytical formulas for estimating R 2 shrinkage, with 4 fully crossed factors (squared population multiple correlation coefficient, number of predictors, sample size, and degree of multicollinearity) and 500 replications in each cell. The results indicated that the most widely used Wherry formula (in both SAS and SPSS) is probably not the most effective analytical formula for estimating ρ2. Instead, the Pratt formula and the Browne formula outperformed other analytical formulas in estimating ρ2 and ρc 2, respectively.  相似文献   

15.
To test the hypothesis that the etiology of reading difficulties may differ for males and females in more severely impaired samples, reading performance data from monozygotic (MZ), same-sex dizygotic (DZss), and opposite-sex dizygotic (DZos) twin pairs were analyzed using a model-fitting implementation of the DeFries-Fulker (DF) model (Purcell & Sham, 2003, Behavior genetics, 33, 271–278). Five non-independent samples were selected using cut-offs of −1 (N = 737 pairs), −1.5 (N = 654), −2 (N = 468), −2.5 (N = 335), and −3 (N = 198) standard deviations (s) below the mean composite reading score of control twins. Male/female gender ratios for children with reading difficulties were significantly higher than 1.0 for all five samples and increased as a function of severity (viz., 1.15, 1.17, 1.40, 1.61, and 1.88, respectively). When the DF model was fit to the data, estimates of heritability (h g2) and shared environmental influences (c g2) were not significantly different for males and females in any of the groups. Consequently, the most parsimonious model that provided a good fit to the data at all five levels of severity equated the heritabilities and shared environmental influences for males and females, and fixed the DZos coefficient of genetic relatedness at 0.5. Thus, these results provide no evidence for a differential etiology of reading difficulties as a function of gender in more severely impaired samples, and suggest that the same genetic and environmental influences contribute to reading difficulties in males and females, irrespective of severity.  相似文献   

16.
Background： Recent autopsy study showed a high incidence ofcerebrovascular lesions in Alzheimer＇s disease （AD）. To assess the impact of cerebrovascular pathology in AD, we used diffusion tensor imaging （DTI） to study AD patients with and without cerebrovascular lesions. Materials and Methods： Conventional and DTI scans were obtained from 10 patients with probable AD, 10 AD/V patients （probable AD with cerebrovascular lesions） and ten normal controls. Mean diffusivity （D） and fractional anisotropy （FA） values of some structures involved with AD pathology were measured. Results： D value was higher in AD patients than in controls in hippocampus and the cingulate gyrus. In AD/V patients, increased D value was found in the same structures and also in the thalamus and basal ganglia compared to controls. There was a significant difference of D value between AD and AD/V patients. FA value reduced in the white matter of left inferior temporal gyrus and in the bilateral middle cingulate gyrus in patients with AD/V compared with controls. The MMSE （mini-mental state examination） score significantly correlated with FA value in the right hippocampus （r=0.639, P〈0.019）, in the right anterior cingulate gyrus （r=0.587, P〈0.035） and in left parahippocampal gyrus （r=0.559, P〈0.047）. Conclusion： Cerebrovascular pathology had stronger impact on the D value than the AD pathology alone did. Elevated D value in thalamic and basal ganglia may contribute to cognitive decline in AD/V patients. Reduced FA values in AD/V patients may indicate that cerebrovascular pathology induced more severe white matter damage than the AD pathology alone did.  相似文献   

17.
1 Introduction Interior-point methods (IPMs) for semidefinite opti-mization (SDO) have been studied intensively,due totheir polynomial complexity and practical efficiency.In the past decade , SDO has become a popular re-search area in mathematical programming when it be-came clear that the algorithm for linear opti mization(LO) can often be extended to the more general SDOcase. Other two factors are also responsible for thisincreasing interest in SDO. Firstly, SDO has a wideapplication…  相似文献   

18.
The effects of salinity(50 mmol/L NaCl) and Cd(1 μmol/L CdCl2) as sole and combined on growth and photosyn-thetic parameters were studied using two soybean genotypes,Huachun 18 and NGB.The concentrations of Cd2 ,Zn2 ,Ca2 ,Mg2 ,K and Na were also determined in seeds and pods.Huachun 18 suffered a more serious decrease than NGB in net photosynthetic rate(Pn) in the treatments of salinity stress alone and combined stress(NaCl Cd),showing that it is relatively sensitive to salinity.The decrease in Pn caused by salt stress in Huachun 18 was mainly due to the reduced total chlorophyll content and photosynthetic efficiency(the ratio of variable fluorescence to maximal fluorescence,Fv/Fm),whereas the decease in NGB was mainly related to reduced stomatal conductance(Gs).The combined stress of both Na and Cd did not induce further decrease in photosynthesis and fluorescence in the two genotypes relative to salt or Cd stress alone.Greater change in the pod concentrations of Zn2 ,Ca2 ,Mg2 ,K and Na was detected under salt stress for Huachun 18 than for NGB.The results suggested that the interactive effect of NaCl-Cd on growth and nutrient uptake differs between the two soybean genotypes.  相似文献   

19.
INTRODUCTION Telomeres are distinctive DNA-protein struc-tures that cap the ends of linear chromosomes.It is very important to keep the chromosomes stabilization.Telomerase activity is closely linked to attainment of cellular immortality,a step in carcinogenesis,while lack of such activity contributes to cellular senes-cence.Telomerase is activated in more than85%ofmalignant tumors(Hiayma et al.,1997).Human te-lomeric repeat binding factor1(TRF1)is a telomere associated with proteins a…  相似文献   

20.
Conclusions In spite of very high toxic potency of PAH, in India environmental monitoring and assessment of PAH is rarely done compared to European countries and US. The Central Pollution Control Board (CPCB) had recently initiated regular monitoring of PAHs in ambient air in select cities. According to CPCB, ambient air PAH in Delhi ranged between 9.4–60.9 nanograms per cubic meter (ng/m3) during 1999–2000 with higher values recorded in winter. Other research studies reported about 4.999.56 ng/m3 of benzo[a]pyrene in suspended paniculate matter (SPM) during 1986 in urban Delhi. In Calcutta, sum of 12 PAHs was 22.91 and 190.96 ng/m3 in SPM at Jadavpur and Maulali respectively, in 1994. The average benzo[a]pyrene concentration was 10.4+4.76 ng/m3. These levels are apparently manifold higher than the European standards. Apart from few such studies no detailed studies are available in India. Even in the current standards and specifications for diesel engines there is no emission limit for PAH. Recently it had specified that 10% of PAH by hydrocarbons as limit that should be adopted by 2005. In the current Indian scenario, especially after the economic liberalization in 1991, the motor vehicle population is increasing rapidly, leading to corresponding increase in PAH emissions. The role of PAHs in cardiovascular mortality, cancer cases and several other health abnormalities that are reported nowadays cannot be ignored.  相似文献   

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