Based on a concept of the hyperfocal distance from photographic lens,this study proposes that emmetropia presents far-hyperfocal distance,near-hyperfocal distance and accommodative hyperfocal distance.When emmetropic presbyopias completely lose the ability of accommodation,its farthest blur point is not beyond 1.5 m,even not being at infinity,and the phenomenon of dark focus both completely match with the definition of hyperfocal distance.On the other hand,after cycloplegic mydriatics in emmetropia,it could be found in the region of depth-of-field that there is no change in the back depth of field (clearness in far vision),but change was found in the front depth of field (blur in near vision).It conforms well to the definition of the hyperfocal distance,demonstrating that human eyes belong to the hyperfocal distance optical system.Furthermore,it is reported that the emmetropic presbyopias rarely matched the spectacles higher than +2.50 D in their whole life;therefore,it can be inferred that their accommodative amplitude in youth is equal to this corrected value.This value accounts for about 4％ of the total refractive power in human eyes,so it is suggested that human eye is a micro zoom optical system.Based on the objective existence of hyperfocal distance,the author proposes that human eye is an integrated accommodative mechanism.It includes three components:the accommodative mechanism of near vision,the measuring and controlling mechanism of near vision,and the general control of near vision.This paper discusses the accommodative mechanism of near vision and the resting mechanism of distance vision based on the hyperfocal distance,and considers that when human eye transfer into the accommodation of near vision from the normal distance vision of hyperfocal distance.There are three different pushing forces contributing to lens deformation and its anterior shift,and these forces cause four different accommodative efforts,which constitute the real accommodative efforts in the relative tissue.This paper also points out that it is only the mode of pushing accommodation that can make the lens vary refraction quickly and greatly,and control the amount of deformation effectively.That can not be achieved by the stretching mode proposed by Tscherning & Schachar,because some authors have verified that excessive pulling would result in decline in the refraction,which would be difficult to regulate and control the eye.Similarly,the self-bulging mode of Helmholtz & Gullstrand will not work neither,because it is unable to control the amount of lens deformation that is its fatal defect.

The change of library space is driven by various factors, such as technology innovation, users demand and the changing competitive environments. The evolution processes of library space were thus clarified by retrie-ving CNKI, namely from computer and IT to Internet and wide application of information and communication tech-nology, from physical space to virtual space, from space function to information commons, learning, pioneering work and social intercourse, which can eventually lead to the intelligent, individual and ubiquitous library space.

Choroid neovascularization (CNV) is pathological proliferation of choroid vascular,accompanying with bleeding and leakage,is one of the major factors caused blindness,so CNV inhibitors have become a research hotspot.At present,researches on inhibitors of vascular endothelial growth factors and their receptors,endogenous angiogenesis factors,redox and inflammatory response related factors,etc,have achieved certain progresses.In addition,as drugs with multiple targets for treatment,many Chinese herbs also show inhibition effect on CNV.This article reviews the research advances in inhibitors for CNV.

Objective:To investigate the effect of catgut implantation at acupoint,Compound Erxian Decoction on levels of serum cytokine in ovariectomized rats.Methods:Sixty 3-month-old female Sprague-drawley rats,weighed 230?20g each,were divided into six groups,ten rats in each group.The first group were sham-operated(Sham-G),while the remaining groups,established by excising both sides ovary,were catgut-acupuncture group(CAG),Chinese herb group(CHG),catgut-acupuncture plus Chinese herb group(CCG),estrogen group(EG)and model group(MG).There wasn’t any therapy in sham-operated group and model group.After 12 weeks corresponding therapy,all groups were sacrificed to procure blood serum for testing the contents of E 2 ,GM-CSF,IGF-1,TNF-?by means of radioimmunoassay and both retral thighbone for testing bone mineral density(BMD) and bone mineral content(BMC)in each specimen.Results:The BMD and BMC of thighbone,E 2 and IGF-1 of serum and in CAG,CHG,CCG and EG was compared with Sham-G,there was no significant difference,but which was higher than MG(P

Objective To investigate the distribution of vitamin D receptor(VDR) gene BsmI and Tru9I site gene polymorphism in children in Guangxi region.Methods Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method and DNA sequencing technology were used to analyze the VDR genotype in 268 healthy children [including 143 boys and 125 girls which aged (4.15?0.63) years] in Guangxi region.Hardy-Weinberg balance analysis was used to check up the samples.Results There were 246 cases which were bb genotgpes in BsmI site and 21 cases which were Bb genotypes and 1 case which was BB genotypes in 268 cases.The frequency of bb,Bb and BB in BsmI site were 91.79%,7.84% and 0.37%,respectively.Frequencies of b and B allelic gene were 95.71% and 4.29%;There were 12 cases which were tt genotypes in Tru9I site and 85 cases which were Tt genotypes and 171 cases which were TT genotypes in all 268 cases.tt,Tt and TT in Tru9I site were 4.48%,31.72% and 63.80%,respectively.Frequencies of t and T allelic genes were 20.34% and 79.66%.The result of PCR-RFLP was according to the result of DNA sequencing.The samples had group representation through Hardy-Weinberg balance analysis.Conclusions The polymorphism frequency and distribution of VDR gene BsmI and Tru9I site gene polymorphism of children in Guangxi region of China exhibit its own characteristics.BB and tt genotypes minority.

Idiopathic thrombocytopenic purpura(ITP) has been confirmed a clinical syndrome because platelets are much destroyed by immunologic mechanism,it is also called immunethrombocytopenic purpura.The pathogenesis of that is very multiplicity,and at present it isn′t understood.This review article is about study progress of B lymphocyte abnormal and the possible pathogenesis of ITP in children.

Objective To study the glucose-6-phosphate dehydrogenase(G6PD)genotypes in the children of viral hepatitis with G6PD deficiency and investigate the relationship between G6PD deficiency and viral hepatitis.Method DNA samples of 18 children with viral hepatitis/ G6PD deficiency were studied for the 3 common mutations by using the natural primers or mismatched primers mediated PCR followed by restriction enzyme analysis and their clinical manifestation was analyzed.Results Among 18 cases,8 cases were G1388A,and 4 cases were G1376T,and 1 case was A95G.The 3 mutations of G1388A,G1376T and A95G added up to 72.22%.There were no significant difference between the patients with viral hepatitis/ G6PD deficiency and the children only with G6PD deficiency.The incidence rates of acute hemolysis and acute renal failure in the viral hepatitis/G6PD deficiency patients were higher than those in children with G6PD deficiency only.Conclusions It is supposed that the G6PD deficiency is primary in the patients of viral hepatitis with G6PD deficiency.The children of viral hepatitis with G6PD deficiency have more severe pathogenetic conditions and more complications than the children with G6PD deficiency only.

It is therapeutically effective to apply hemopoietic growth factors to treat hemopoietic irradiation injuries, but for other tissues injuries, hemopoietic growth factors nearly do not work. At the same time, they are only suitable for the patients with severe and lower level acute radiation sickness (ARS). Besides, clinical therapeutic efficacy of marrow transplantation is not optimistic due to difficulties of marrow zygosity and severe complications such as graft versus host disease, radiation interstitial pneumonitis. Mesenchymal stem cells (MSCs) could secret hemopoietic growth factors, rebuild hemopoietic microenvironment and be easily transfected by exogenous gene, which also have low immunogenicity. At present, studies on MSCs application in the treatment of radiation injuries are at the early -stage, but the precise mechanism is not clear. However, the specific characteristics can make up the disadvantage of traditional treatment of acute radiation sickness, and the clinical application is wide.

Objective To observe the relationship between the intima media thickness(IMT) and the level of serum uric acid in elderly female patients with hypertension Methods Eighty elderly female patients with hypertension were measured for carotid artery average IMT and the level of serum uric acid They were divided into the normal group, intima thicking group ,the plaque shaping group and the vascular stenosis group. In the abnormal groups, probable risk factors were analysed by multiple stepwise regression Results There were significantly differentces among these groups ( P

Objective To investigate the clonal rearrangement of T cell receptor (TCR) ? gene which was of monoclonality,oligoclona-lity or clonal evolution /subclonality during the course of disease in patients with acute lymphoblastic leukemia (ALL) and its significance.Methods Between Sep. 2004 and Sep. 2007,70 patients with ALL were diagnosed in Department of Pediatrics of the First Affiliated Hospital of Guangxi Medical University,among which 51 cases were boys and 19 cases were girls.Their ages ranged from 2 years to 14 years (average age was 8.5 years).DNA samples were extracted from bone marrow cells or venous blood cells by phenol/phenol-isoamyl alcohol-chloroform/isoamyl alcohol law.DNA was amplified by polymerase chain reaction (PCR).Single strand conformation polymorphism analysis (SSCP) of silver stained technique was employed to detect PCR products.Results The amplification products of 23 cases of the 70 ALL patients were positive,in which 10 cases still had positive results in period of complete remission and had poor sensitivity to chemotherapeutic drugs,4 cases were of oligoclonality/ subclonality,and 2 cases were of clonal evolution with poor prognosis.Conclusions Detecting TCR ? gene rearrangement reflects clonal evolution of leukemia cells.The oligoclonality clonal evolution continues to exist,whose multiplication is the main reason of recurrent ALL.Detecting TCR? gene rearrangement,evaluating ALL of the patient's prognosis,the judgment of recurrence and the development of individualized treatment programs have great guiding significance,which can maximize the possibility of the sick children to make long-term disease-free survival and reduce the side effects of chemotherapy on the long-term basis.