Asset specificity and farmers' intergenerational succession willingness of apple management

Understanding the factors behind apple farmers’willingness to pass on the management of their farms to their descendants is crucial to the continuity of apple production.Due to the high specificity of the human capital,physical assets,land assets,and geographical location in apple production,this study used a binary logistic regression and a mediating effect model to explore the impact of asset specificity on farmers’intergenerational succession willingness of apple management(FISWAM)and to examine the mediating effects of loss aversion in the impact of asset specificity on the FISWAM.The results showed that about 18.68%of the respondents expressed willingness to transfer their apple business between generations,and the FISWAM was generally weak.In addition to the negative impact of geographical location specificity(GLS),human capital specificity(HCS),physical assets specificity(PAS),and land assets specificity(LAS)can enhance the FISWAM.Loss aversion plays a partial mediating role in the impact of PAS,LAS,and GLS on the FISWAM.

Sensitivity and specificity of hearing tests for screening hearing loss in older adults

Objectives: The study aimed to determine the most appropriate hearing screening test to identify disabling hearing loss for adults aged 65 years or older.Methods: This study included 577 older adults. Four hearing screening tests were considered in the study, including the Hearing Handicap Inventory for Elderly Screening(HHIE-s), three single question tests, the whisper test, and the finger rub test. The sensitivity and specificity of these tests referenced to the hearing threshold of disabling hearing loss were estimated.Results: Among all tests, only the single self-perception question(0.7064 for sensitivity;0.7225 for specificity) and whisper test(0.7833 for sensitivity;0.7708 for specificity) could obtain both sensitivity and specificity higher than 70% for adults aged ≥65 years.Conclusion: Overall, we suggest using the whisper test to identify disabling hearing loss(>40 dB HL at the better ear) for adults aged 65 years or older. However, if the conditions do not permit, the single selfperception question is also acceptable. Moreover, HHIE-s might not be a good test to detect disabling hearing loss for adults aged 80 years or older.

Adaptive Graph Embedding With Consistency and Specificity for Domain Adaptation

Domain adaptation(DA) aims to find a subspace,where the discrepancies between the source and target domains are reduced. Based on this subspace, the classifier trained by the labeled source samples can classify unlabeled target samples well.Existing approaches leverage Graph Embedding Learning to explore such a subspace. Unfortunately, due to 1) the interaction of the consistency and specificity between samples, and 2) the joint impact of the degenerated features and incorrect labels in the samples, the existing approaches might assign unsuitable similarity, which restricts their performance. In this paper, we propose an approach called adaptive graph embedding with consistency and specificity(AGE-CS) to cope with these issues. AGE-CS consists of two methods, i.e., graph embedding with consistency and specificity(GECS), and adaptive graph embedding(AGE).GECS jointly learns the similarity of samples under the geometric distance and semantic similarity metrics, while AGE adaptively adjusts the relative importance between the geometric distance and semantic similarity during the iterations. By AGE-CS,the neighborhood samples with the same label are rewarded,while the neighborhood samples with different labels are punished. As a result, compact structures are preserved, and advanced performance is achieved. Extensive experiments on five benchmark datasets demonstrate that the proposed method performs better than other Graph Embedding methods.

Astrocyte evolution and human specificity

The cerebral cortex is one of the most complex structures of the mammalian central nervous system and accounts for the extraordinary cognitive abilities in primates and humans.Since the 19th century,neur ons have been believed to be the main players in the building of the brain,yet astrocytes also play a crucial role as fundamental building blocks of the cerebral cortex complexity.

A study of acupoint specificity and mechanism of electroacupuncture intervention on chronic colitis in rats based on PI3K/AKT/mTOR signaling pathway

Objective:This study aimed to elucidate the differences in effects and mechanisms of action of electric-needle therapy at Tian Shu(ST25),Da Chang Shu(BL25),Zu San Li(ST36)and Shang Ju Xu(ST37)acupoints on chronic experimental colitis in rats through the PI3K/AKT/mTOR signaling pathway.Methods:Sixty pathogen-free SD rats were randomly assigned to six groups:the normal,model,Tian Shu(ST25),Da Chang Shu(BL25),Zu San Li(ST36)and Shang Ju Xu(ST37)groups,each with 10 rats.Chronic colitis was induced in rats by combining immunization and local stimulation.After model establishment,electrical needle intervention combined with dispersing wave of 2 Hz/50 Hz with a current intensity of 2 mA once daily for 20 min was applied on acupoints of each group.Subsequently,the inflammation of colonic mucosa and serum levels of inflammatory factors(IL-23,IL-17,IL-10)were observed;ELISA was used to detect mRNA expressions of PI3K,Akt and mTOR in colitic tissues by RT-PCR as well as protein content of p-PI3k/PI3K,p-Akt/Akt,and p-mTOR/mTOR in colitic tissues by Western blotting.Result:Compared with the normal group,the model rats showed a poor general condition,serious damage to the colonic mucosa with a large number of inflammatory cells infiltration.The serum IL-23 and IL-17 expressions were significantly increased(P<0.01),while the serum IL-10 expression was significantly decreased(P<0.01);the mRNA and protein expressions of PI3K,Akt,mTOR and p-PI3K,p-Akt and p-mTOR were significantly increased(P<0.05,P<0.01).Compared with the model group,the pathological slices of rats in each acupoints intervention group showed obvious improvement of colitis inflammatory reaction and tissue damage;the serological levels of IL-23 and IL-17 were significantly reduced(P<0.01),while the serology level of IL-10 was significantly increased(P<0.01);the expressions of PI3K,Akt,mTOR mRNA and p-PI3K,p-Akt,p-mTOR proteins were significantly decreased(P<0.05,P<0.01).Compared with Tian Shu(ST25),Da Chang Shu(BL25),Zu San Li(ST36)groups,the recovery degree of mucosa layers in Shang Ju Xu(ST37)group was closer to that of normal group,and the curative effect was relatively the best;in terms of serological levels of IL-23 and IL-17,the Shang Ju Xu(ST37)group was significantly lower(P<0.05),while the level of IL-10 was significantly higher(P<0.01);the expressions of PI3K,Akt,mTOR mRNA and p-PI3K,p-Akt,p-mTOR proteins were significantly decreased(P<0.05,P<0.01).Conclusion:Results indicate that electrical acupuncture at Tian Shu(ST25),Da Chang Shu(BL25),Zu San Li(ST36)and Shang Ju Xu(ST37)show similar effects in relieving the colitis-induced damage in the mucosa of chronic colitis rats,as well as inflammatory response.Among them,Shang Ju Xu(ST25)has a superior overall effect in treating chronic colitis compared to Tian Shu(ST25),Da Chang Shu(BL25)and Zu San Li(ST36).The mechanism may be related to inhibition of PI3K/Akt/mTOR signaling pathway.

A Simple and Rapid Method to Determine the CO_2/O_2 Specificity Factor for Rubisco

A simple and rapid new method is presented to determine the CO 2/O 2 specificity factor for ribulose_1,5_bisphosphate(RuBP) carboxylase/oxygenase (Rubisco). In principle, the quantitative formula, which intrinsically resulted in error or enormous error in all reported methods, was improved to circumvent the problem. In practice, the complicated procedure with radiolabelling and chromatographic separation of 3_phosphoglycerate and 2_phosphoglycolate was substituted by one_step procedure without radiolabelling and chromatographic separation to decrease the random error. The effects of pH, temperature and ionic strength on accuracy of the data and the reliability of the calculation of the CO 2/O 2 specificity factor are also discussed.

Analysis of Seed-specificity of Silencing fad_2 Gene Expression in Transgenic Rapeseed Line W-4(Brassica napus L.)

This study was to investigate the efficiency and specificity of RNAi silencing on the expression of endogenous fad2 gene in transgenic line W-4. [Method] The relative expression of fad2 gene in seeds at different developmental stages of 7th, 14th, 21st and 28th day after flowering （DAF） as wel as the root, stem, leaf at winter seedling stages of both the transgenic line W-4 and non-transgenic control Westar by real-time fluorescence quantitative PCR. [Results] The results showed the relative expression of fad2 gene was gradual y increasing with the days after flowering in the seeds of the control Westar, while it was found decreasing significantly since the 21st DAF in the seeds of the line W-4. The decline was up to 60% in comparison with the control Westar. However, no significant difference in the relative expression of fad2 gene in other organs like root, stem and leaf was observed between transgenic line W-4 and non-transgenic control Westar. Fatty acid composition analysis showed the oleic acid desaturation parameter（ODP） in seeds of the line W-4 was 0.07 in average, decreased by nearly 75% than control Westar which was 0.24 in average, while no significant difference in the seedling root, stem and leaf was measured between transgenic rapeseed and control. [Conclusion] The results above validated that RNA interference in transgenic rapeseed W-4 is at a seed-specific manner, not interfering with fad2 gene expression in organs such as the root, stem and leaf. The study also found that the period of fad2 gene expres-sion decline was wel coincided with the expression of napin gene, both appeared at the 21st DAF, indicating that the expression of dsRNA of fad2 gene is precisely control ed by the napin promoter.

Phylogenetic diversity and specificity of bacteria associated with Microcystis aeruginosa and other cyanobacteria

Interactions between bacteria and cyanobacteria have been suggested to have a potential to influence harmful algal bloom dynamics; however, little information on these interactions has been reported. In this study, the bacterial communities associated with five strains of Microcystis aeruginosa, three species of other Microcystis spp., and four representative species of non-Microcystis cyanobacteria were compared. Bacterial 16S rDNA fragments were amplified and separated by denaturing gradient gel electrophoresis （DGGE） followed by DNA sequence analysis. The similarities among bacterial communities associated with these cyanobacteria were compared to the digitized DGGE profiles using the cluster analyses. The bacterial community structure of all cyanobacterial cultures differed. Cluster analysis showed that the similarity values among M. aeruginosa cultures were higher than those of other cyanobacterial cultures. Sequence analysis of DGGE fragments indicated the presence of bacteria including, Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Bacteroidetes and Actinobacteria in the cyanobacterial cultures. Members of the Sphingomonadales were the prevalent group among the Microcystis-associated bacteria. The results provided further evidence for species-specific associations between cyanoabcteria and heterotrophic bacteria, which are useful for understanding interactions between Microcystis and their associated bacteria.

Expression and role of specificity protein 1 in the sclera remodeling of experimental myopia in guinea pigs

AIM：To study the expression of collagen I and transcription factor specificity protein 1（Sp1）,a transforming growth factor-β1（TGF-β1） downstream target,and reveal the impact of the TGF-β1-Sp1 signaling pathway on collagen remodeling in myopic sclera.METHODS：Seventy-five 1-week-old guinea pigs were randomly divided into normal control,form deprivation myopia（FDM）,and self-control groups.FDM was induced for different times using coverage with translucent latex balloons and FDM recovery was performed for 1wk after 4wk treatment;then,changes in refractive power and axial length were measured.Immunohistochemistry and reverse transcription-polymerase chain reaction were used to evaluate dynamic changes in collagen I and Sp1 expression in the sclera of guinea pigs with emmetropia and experimental myopia,and the relationship between collagen I and Sp1 levels was analyzed.RESULTS：In the FDM group,the refractive power was gradually changed（from 2.09±0.30 D at week 0 to-1.23±0.69 D,-4.17±0.59 D,-7.07±0.56 D,and-4.30±0.58 D at weeks 2,4,6,and 1wk after 4wk,respectively;P〈0.05）,indicating deepening of myopia.The axial length was increased（from 5.92±0.39 mm at week 0 to 6.62±0.36 mm,7.30±0.34 mm,7.99±0.32 mm,and 7.41±0.36 mm at weeks 2,4,6,and 1wk after 4wk;P〈0.05）.The m RNA and protein expression of Sp1 and collagen I in the sclera of the FDM group was lower than that of the control groups（P〈0.05）,and the reduction was eye-coverage time-dependent.Furthermore,correlation between Sp1 and collagen I down-regulation in the myopic sclera was observed.CONCLUSION：Our data indicate that transcription factor Sp1 may be involved in the regulation of type I collagensynthesis/degradation during myopic sclera remodeling,suggesting that TGF-β1 signaling plays a role in the development and progression of myopia.

Tissue specificity of DNA damage response and tumorigenesis

The genome of cells is constantly challenged by DNA damages from endogenous metabolism and environmental agents.These damages could potentially lead to genomic instability and thus to tumorigenesis.To cope with the threats, cells have evolved an intricate network, namely DNA damage response(DDR) system that senses and deals with the lesions of DNA.Although the DDR operates by relatively uniform principles, different tissues give rise to distinct types of DNA damages combined with high diversity of microenvironments across tissues.In this review, we discuss recent findings on specific DNA damage among different tissues as well as the main DNA repair way in corresponding microenvironments, highlighting tissue specificity of DDR and tumorigenesis.We hope the current review will provide further insights into molecular process of tumorigenesis and generate new strategies for cancer treatment.

THE EXTENSIVENESS AND SPECIFICITY OF EFFECT OF ELECTROACUPUNCTURE AT DIFFERENT ACUPOINTS ON NOCICEPTIVE RESPONSE OF CONVERGENT NEURONS IN TRIGEMINAL NUCLEUS CAUDALIS

Experiments were carried out on rats anaesthetized with uraethane. The sponta-neous discharges and nociceptive responses of convergent neurons in the right trigerninal nucleus cau-dalis(TNC) to noxious stimuli at receptive field (cheek) were recorded extracellularly with glass mi-cro-electrode. Electroacupuncture (EA ) was applied at bilateral " Xiaguan" (ST 7 on face ) or "Zusanli" (ST 36 on shank) acupoint with Iow (2V) and high (18V) intensity. The noclceptive re-sponse of convergent neurons in TNC could be inhihited by low intensity EA applied at "Xiaguan" butnot "Zusanlil", showing the specificity of acupoints. High intensity EA at either "Xiaguan" or "Zusan-li" also reduced the nociceptive responses, showing the analgesic extensiveness of acupoints. We sug-gest that "the gate of control" mechanism plays a main role in low intensity EA and "diffuse noxiousinhibitory controls" (DNIC) rnechanism does so in high intensity EA.The results suggest that we should pay attention to the location of acupoints,

Evaluation of the Sensitivity and Specificity of the New Clinical Diagnostic and Classification Criteria for Kashin-Beck Disease,an Endemic Osteoarthritis,in China

This study aimed to evaluate the sensitivity and specificity of the new clinical diagnostic and classification criteria for Kashin-Beck disease （KBD） using six clinical markers： flexion of the distal part of fingers, deformed fingers, enlarged finger joints, shortened fingers, squat down, and dwarfism. One-third of the total population in Linyou County was sampled by stratified random sampling.

Identification of highly conserved domains in hemagglutinin associated with the receptor binding specificity of influenza viruses: 2009 H1N1, avian H5N1, and swine H1N2

The hemagglutinin (HA) of influenza viruses facilitates receptor binding and membrane fusion, which is the initial step of virus infection. Human influenza viruses preferentially bind to receptors with α2-6 lin- kages to galactose (SAα2,6Gal), whereas avian influenza viruses prefer receptors with α2-3 linkages to galactose (SAα2,3Gal). The current 2009 H1N1 pandemic is caused by a novel influenza A virus that has its genetic materials from birds, humans, and pigs. Its pandemic nature is characterized clearly by its dual binding to the α2-3 as well as α2-6 receptors, because the seasonal human H1N1 virus only binds to the α2-6 receptor. In a previous study, the informational spectrum method (ISM), a bioinformatics technique, was applied to uncover one highly conserved region in the HA protein associated with receptor binding preference in each of various influenza subtypes. In the present study, we extended the previous work by discovering multiple such domains in HA of 2009 H1N1 and avian H5N1 to expand our repertoire of known key regions in HA responsible for receptor binding affinity. Three such domains in HA of 2009 H1N1 were found at residue positions 106 to 130, 150 to 174, and 191 to 221, and another three domains in HA of avian H5N1 were located at residue positions 46 to 65, 136 to 153, and 269 to 286. These identified domains could be utilized as therapeutic and diagnostic targets for the prevention and treatment of influenza infection.

PGC-1α differentially regulates the mRNA expression profiles of genes related to myofiber type specificity in chicken

Previous studies on mammals showed that peroxisome proliferator-activated receptor gamma coactivator-1α(PGC-1α)played a prominent role in regulating muscle fiber type transition and composition.However,the role of PGC-1αin chicken muscle has seldom been explored.To investigate the effect of PGC-1αon chicken skeletal muscles in this study,the PGC-1αgene was overexpressed or silenced in chicken primary myoblasts by using lentivirus,and then the effects of the PGC-1αgene overexpression and knockdown on the mRNA expression profile of genes related to myofiber type specificity were examined during fiber formation.The results showed that overexpression of PGC-1αfrom proliferation to differentiation was accompanied by the up-regulated expression of Pax7,MyoD,and CnAα,which was significantly(P<0.01)increased after one day of transfection(1 I).The enhancement of MyoG,MEF2 c,and MyHC SM expression lagged,which was improved significantly(P<0.01)after four days of transfection(1 I3 D).Overexpression of PGC-1αdecreased(P<0.01)the MyHC FWM expression after four days of transfection(1 I3 D),and it had no significant impact(P>0.05)on the expression of CnB1,NFATc3,and MyHC FRM during myofiber formation.The effective silence(P<0.01)of PGC-1αby lentivirus mediating short hairpin RNA(shRNA)was detected after four days of transfection(1 I3 D)in cultures,and the lack of its function in chicken primary myoblasts significantly(P<0.01)down-regulated the expression of Pax7,MyoD,CnAα,MyoG,MEF2 c,and MyHC SM,significantly(P<0.01)up-regulated the expression of MyHC FWM,and had no significant impact(P>0.05)on the expression of CnB1,NFATc3,and MyHC FRM.These results indicated that the role of PGC-1αin regulating the fiber type specificity of chicken skeletal muscles might be similar to that in mammals,which interplayed with key genes related to myocyte differentiation and calcineurin signaling pathway.

Cerebral functional imaging of Waiguan (SJ 5) acupoint specificity using single-photon emission computed tomography

The action of needling in acupoint therapy has to first be regulated and integrated by the brain, and then it affects the target organ and manifests its therapeutic effects, which is dependent on the specificity of the acupoints. The authors put forward the hypothesis of the ＂acupoint-related brain＂. Single-photon emission computed tomography was used to explore the activation of brain regions following true needling in true acupoint Waiguan （SJ 5）, sham needling in true acupoint Waiguan, true needling in a sham point, and sham needling in a sham point. The relative specificity of Waiguan in normal persons was analyzed by observing changes in regional cerebral blood flow. Compared with the sham needling in true acupoint group and sham needling in the sham point group, acupuncture at Waiguan can activate brain regions controlling movement. Compared with true needling in the sham point group, acupuncture at Waiguan can also activate brain regions controlling movement. The results suggest that the specificity of needling at an acupoint is related to certain activated cerebral functional regions, which are associated with the clinical application of the acupoint.

Some Evidence for Host Specificity in Arbuscnlar Myc-orrhizas

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Specificity and sensitivity of visual evoked potentials P100 latency to different events exercise

Visual evoked potentials (VEPs) are a series of signals about visual occipital cortex in response to visual stimuli and can be used as one of ob-jective non-invasive neuro-physiological pa-rameters to reflect the visual organs and central visual pathway’s functional integrity. Previous studies have shown that acute and chronic ex-ercise could affect VEPs independent from body temperature and other physiological parameters. VEPs may well be used as neuro-physiological criteria in defining the performances of the ath-letes. Different sports training have different effects on VEPs, but the results are not consis-tent. P100 latency is the representative compo-nent of VEPs and it is of high, steady amplitude and of slight intra- and inter-individual variabil-ity so that the index is most commonly used. The purpose of this study was to investigate the specificity and sensitivity of P100 latency to dif-ferent physical activities. The neural electricity device of NDI-200 was used to measure the pattern reversal VEPs of all subjects, including the values of the resting state before and after different events exercise. Different events exer-cise contained an aerobic cycloergometric ex-ercise (7 subjects were conducted to a Bruce Graded Exercise Test on the Monark Ergomedic 839E cycloergometer, THR (target heart rate) = 85% HRmax, 3 times/week, about 10 minutes once time, 6 weeks), tennis training (16 volun-teers, 2 hours/day, 3 days/week, 8 weeks), aerobic Latin exercise (7 subjects, 1 hour/day, 3 days/week, 6 weeks) and the Baduanjin of Health Qigong training (6 subjects, 1 hour/day, 3 days/week, 6 weeks). The VEPs recordings of the control groups obtained synchronized with the experimental groups. SPSS 11.5 for win-dows was used for statistical analysis. A level of P﹤0.05 was accepted as statistically significant. The VEPs P100 latency of post-exercise of all experimental groups except Baduanjin group became shorter significantly compared with those of pre-exercise (P﹤0.05). No significant difference was found between pre-and post- exercise for the control groups. This study showed that exercise could shorten the P100 la-tency significantly. Moreover, it also indicated that VEPs were sensitive to exercise to a certain extent. We concluded that VEPs might well be used as neuro-physiological criteria in defining the performances of the athletes. It was found that the VEPs P100 latency became shorter after most training programs;furthermore, it demon-strated that P100 latency of VEPs had little specificity to different events.

Application of Current Hapten in the Production of Broad Specificity Antibodies Against Organophosphorus Pesticides

Diethylphosphono acetic acid （DPA） was used as a current hapten to generate broad specificity polycolonal antibodies against a group of organophosphorus pesticides. Six New Zealand white rabbits were immunized with immunogens synthesized by the active ester method （AEM） or 1-ethyl-3-（3-dimethylaminopropyl）-carbodimide method （EDC）. The titers of antisera reached 25 600 by AEM and 6 400 by EDC, respectively. Polyclonal antibodies raised against DPA were screened and selected for the competitive indirect enzyme-linked immunosorbent assay （CI-ELISA）. A CI-ELISA for DPA was developed with a detection limit of 3.536 ng mL^-1and an I50 value of 0.182 μg mL^-1. The assay specificity was evaluated by obtaining competitive curves for several structurally related compounds as competitors. The antiserum showed high affinities to chlorpyrifos, diazinon, omethoate, parathion-ethyl and profenofos with I50 of 0.12, 0.15, 0.21, 0.88, 0.97 and 2.5 μg mL^-1, respectively. The results indicate that the assay could be a screening tool for quantitation and semiquantitation determination of the above former five organophosphorus pesticides.

Transcription factors specificity protein and nuclear receptor 4A1 in pancreatic cancer

Specificity protein(Sp)transcription factors(TFs)Sp1,Sp3 and Sp4,and the orphan nuclear receptor 4A1(NR4A1)are highly expressed in pancreatic tumors and Sp1 is a negative prognostic factor for pancreatic cancer patient survival.Results of knockdown and overexpression of Sp1,Sp3 and Sp4 in pancreatic and other cancer lines show that these TFs are individually pro-oncogenic factors and loss of one Sp TF is not compensated by other members.NR4A1 is also a prooncogenic factor and both NR4A1 and Sp TFs exhibit similar functions in pancreatic cancer cells and regulate cell growth,survival,migration and invasion.There is also evidence that Sp TFs and NR4A1 regulate some of the same genes including survivin,epidermal growth factor receptor,PAX3-FOXO1,α5-andα6-integrins,β1-,β3-andβ4-integrins;this is due to NR4A1 acting as a cofactor and mediating NR4A1/Sp1/4-regulated gene expression through GC-rich gene promoter sites.Several studies show that drugs targeting Sp downregulation or NR4A1 antagonists are highly effective inhibitors of Sp/NR4A1-regulated pathways and genes in pancreatic and other cancer cells,and the triterpenoid celastrol is a novel dual-acting agent that targets both Sp TFs and NR4A1.

Expression and role of specificity protein 1 and collagenⅠin recurrent pterygial tissues

AIM:To investigate the expression profiles of the transcription factor specificity protein 1(Sp1)and collagenⅠin recurrent pterygial tissues.What is more,to compare the changes of Sp1 and collagen I among primary pterygial tissue,recurrent pterygial tissue and conjunctival tissue.METHODS:In the prospective study,we collected the pterygial tissues of 40 patients who underwent resection of primary pterygial tissue and recurrent pterygial tissue,and the conjunctival tissues of 10 patients with enucleation due to trauma.The relative expression levels of Sp1 and collagen I were analyzed by reverse transcription quantitative-polymerase chain reaction and Western blot.Paired t-test was performed to compare the Sp1 and collagen I of recurrent pterygial tissues,as well as the primary pterygial tissues and conjunctival tissues.In further,Pearson’s hypothesis testing of correlation coefficients was used to compare the correlations of Sp1 and Collagen I.RESULTS:The content of Sp1 and collagen I m RNA and protein was significantly greater in recurrent pterygial tissue than that was in primary and conjunctival tissue(P<0.05).There was a positive correlation between the m RNA and protein levels of Sp1 and collagen I in recurrent pterygial tissues(protein:r=0.913,P<0.05;m RNA:r=0.945,P<0.05).CONCLUSION:Sp1 and collagen I are expressed in normal conjunctival,primary,and recurrent pterygial tissues,but expression is significantly greater in the latter.Sp1 and collagen I may be involved in the regulation of the development of recurrent pterygium.