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The prevalence of myopia in China is increasing. The early onset and rapid progression of myopia in younger children have attracted more attention. The establishment of standardized children's refractive development records is the basis of myopic prevention and control. It would be helpful to follow the refractive status and pay more attention to the refractive development of potential myopic children, so as to reduce the prevalence of myopia.目前我国学生近视眼患病率不断上升，近视眼低龄化趋势不断扩大，已经引起国家和政府的高度重视。为使我国的近视眼防控工作尽早取得实质性效果，本文在阐述规范化建立儿童屈光发育档案意义的基础上，将近视高危学生作为降低近视眼患病率的主体，提出规范化建立儿童屈光发育档案的要点和临床实践意见，希望为眼科临床相关工作提供指导和参考。

Dietary nitrate which mainly comes from green leafy vegetables, is absorbed into blood circulation by the intestinal mucosa. Parotid gland is an important organ for transporting nitrate. Nitrate in blood is taken up by sialin, a nitrate transporter and concentrated in salivary glands and secreted into saliva. The salivary nitrate is partially reduced to nitrite and nitric oxide by oral bacteria, and then salivary nitrate and nitrite return into blood circulation with swallowing and intestinal mucosal absorption. As a non-classic source of nitric oxide, nitrate-nitrite-nitric oxide pathway plays an important role on physiological and pathological conditions, especially on the condition of hypoxia and ischemia. These functions include body protection, such as gastrointestinal tract, cardiovascular system, anti-inflammation, regulation of glucose/lipid metabolism, improvement of sport ability, maintaining gut microbiome hemostasis, and alleviating senility. The traditional view on nitrate as a harmful substance to human body has been proved to be lack of scientific evidence. With further research and application, as a pioneer from the mouth to the whole body, nitrate is expected to play a crucial part in human health, and prevention and treatment of systemic diseases.绿叶蔬菜是饮食硝酸盐的主要来源，饮食硝酸盐由肠黏膜吸收入血。腮腺是机体转运硝酸盐的重要器官，唾液腺通过唾液腺浆液性细胞膜上硝酸盐转运蛋白（sialin）主动摄取血液中的硝酸盐并分泌至唾液。唾液硝酸盐在口腔细菌作用下部分还原为亚硝酸盐及一氧化氮，唾液硝酸盐和亚硝酸盐随吞咽及肠黏膜吸收再次进入循环。硝酸盐—亚硝酸盐—一氧化氮途径是体内一氧化氮非经典来源途径，其在生理和病理状态下发挥重要作用，尤其是在低氧和缺血状态下更明显。这些作用包括机体保护（如胃肠、心血管保护）、抗炎、调节糖脂代谢、提高运动能力、维持肠道菌群平衡及延缓衰老等。以往认为硝酸盐对机体有害的观点被证明缺乏科学依据。随着研究和应用的不断深入，硝酸盐作为从口腔走向全身的使者有望在全身健康及疾病防治中发挥重要作用。.

Adakite is an intermediate to felsic rock with low K, high Al, Na and Sr, and depleted in Y and HREE, usually occurring in arc settings related to subduction of an oceanic slab. Here we report the occurrence of potassic adakites from south Tibet in an orogenic belt produced by the Indo–Asian continent collision. These adakitic intrusives, as a product of Neogene east–west extension, occur in a Miocene Cu-bearing porphyry belt, which developed along the Gangdese arc paralleling the Yarlung–Zangbo suture, but is locally controlled by NS-striking normal faulting systems. Available age data define a duration of magmatism of 10–18 Ma for the adakitic intrusives and related extrusive analogues in south Tibet, which occur in a post-collisional extensional setting. Geochemical data indicate that these adakitic intrusives are shoshonitic and exhibit calc-alkaline composition with high K, and high Sr/Y and La/Y coupled with low Y and HREE, similar to adakites derived from slab melting. However, a wide range for ϵNd(t) (−6.18 to +5.52), initial 87Sr/86Sr (0.7049–0.7079), 207Pb/204Pb (15.502–15.626), and 208Pb/204Pb (38.389–38.960), as well as high K2O contents (2.6–8.6 wt%) and relatively high Mg# values (0.32–0.74) indicate that these adakitic magmas were formed by a complex mechanism involving partial melting of mafic materials in a thickened lower crust with input of enriched mantle and/or upper crust components. Absence of a negative Eu anomaly, extreme depletion in Y, Nb and Ti, and variable high Sr/Y and La/Yb ratios suggest that the lower crustal source is probably a hydrous amphibole eclogite or garnet amphibolite, as exhumed in the western and eastern Himalayan syntaxes on the Tibetan plateau. Partial melting of the lower crust was most likely triggered by mantle-derived ultra-potassic magmatism (17–25 Ma) formed by slab breakoff or mantle thinning. During the formation and migration of pristine adakitic melts, additional input of ultra-potassic magmas and upper crustal materials could account for the observed ϵNd–ϵSr signatures and high Rb/Sr, K and Mg# characteristics for most of the adakitic intrusives in south Tibet.

A simple and effective method for simultaneously determining the refractive index and the wedge angle of an optical wedge plate is described. The method is based on a real-time holographic interferometer which uses a photorefractive crystal as the recording and reconstruction medium. The wedge sample under test is inserted into a rectangular cell that is placed in the object light beam of the holographic interferometer. The interference patterns produced before and after a reference liquid is poured into the cell are received by a CCD camera and stored in a computer, respectively. The refractive index and the wedge angle of the wedge sample are determined by measuring the number of fringes falling inside a fixed aperture. The principle of the method is analysed and some experimental results with adequate accuracy are given.

Type II collagen-induced arthritis (CIA) in mice is an animal model of autoimmune inflammatory arthritis. Arthritis is induced in susceptible strains of mice (H-2q and H-2r) after immunization with heterologous or autologous type II collagen in CFA. Induction of CIA is T cell dependent and a restricted usage of TCR V beta genes has been found in the arthritic joints and lymph nodes of mice with CIA. However, genes within the MHC are not the only determinants of susceptibility to CIA as SWR/j, AU/ssJ (both H-2q) and RIIIS/J(H-2r) mice are resistant to the induction of CIA. These strains of mice are TCR V beta chain genes deletion mutants (TCR V beta a and TCR V beta c haplotypes) and it was hypothesized that these mice are resistant to CIA because of the absence of a particular set of V beta TCR genes that are genomically deleted in these strains of mice. We now show that BUB/BnJ mice (H-2q) are T cell subsets deficient because of the genomic deletion of TCR V beta 5, 8, 9, 11, 12, and 13 sub-families. Our data demonstrate that despite the deficiency in T cell subsets from genomic deletion of TCR V beta genes, BUB mice are highly susceptible to the development of CIA. These results indicate that genomic deletion of certain TCR V beta genes alone is not in itself sufficient to confer resistance to CIA. These results further suggest that other unknown gene(s) must also contribute to the induction of CIA.

1/3 of the main stream dikes of Songhua River are composed of silty soil. In 1998 the superflood of the Songhua River, a great deal of dangers came about from these dikes constructed with silty soil, this article focusing on the destructive condition of the “sand dikes” of Songhua River makes an integration of the Geocell Reinforced Gravel soil and 3D geonet technology and the ecological protection, and combining the engineering practice, it discuss a new ecological protection technology of the sand dikes.

The silty soil dike section takes about 1/3 of the total length of Songhua River dike. The serious dangers of the 1998 superflood all took place at these sections. The dispersed immersion destruction of the back-dike silty soil is one of the main destructive phenomena. This article presents the structures and designs of the geosynthetics preventing the silty soil dike from the dispersed immersion destruction with the danger removing and reinforcement projects of Songhua River dike.

A human granulocyte-macrophage colony stimulating factor (GM-CSF)/interleukin-3(IL-3) fusion gene with a short linker between the GM-CSF and IL-3 gene has been successfully constructed and expressed in E. coli under the control of T7 promoter. The recombinant fusion protein was expressed as inclusion bodies after the IPTG induction. The yield of the GM-CSF/IL-3 fusion protein was over 30% of the total cellular proteins. Western-blotting results showed that the fusion protein could specifically combined with GM-CSF antibody and IL-3 antibody. The biological activity was detected by the GM-CSF and IL-3 dependent cell line TF-1. After solubilizing with 8 mol/L urea and renaturing with dialysis against Tris. HCl solution, the refolded fusion protein showed obvious activities to maintain the growth of TF-1 cell.

The possibility of using lactose as an inducer to substitute the common inducer IPTG in the fermentation process of the recombinant microorganism was deeply investigated. The influences of culture conditions such as lactose concentration, growth medium composition, the point of induction and the duration of the induction phase on the expression of the recombinant protein were analyzed and studied in detail. In the following experiments, lactose was then used in the high cell density culture process of E. coli BL21 (DE3)(pFu). The final cell density (OD600) was over 40. The expression level of recombinant protein was about 15% of the total cellular protein. Both the culture density and foreign protein expression level were lower than those induced by IPTG. However, because of the potential toxicity to human beings and the high cost of IPTG, the use of lactose might provide an alternative means of inducing foreign protein expression. This would be more attractive in industrial scale productions of recombinant proteins. The results confirmed that lactose could be used as an inducer in the fermentation process.

By using intrasplenic immunization and the conventional B lymphocyte hybridoma technique, we have established two novel hybridoma cell lines stably secreting specific monoclonal antibodies (MAbs) to magaininII, termed as 2D1 and 3F8, respectively. The two cell lines were then subjected to RNA extraction and the VH and VL segments were obtained by reverse transcription of RNA followed by polymerase chain reaction (RT-PCR) and characterized by nucleotide sequence analysis. The VH segments of 2D1 and 3F8 belong to the VH5 family and the VL segments of 2D1 and 3F8 belong to VK10 and VK1 groups, respectively. The two MAbs utilize different VL segments and have disparities in their HCDR3 regions, which may contribute to the different epitope recognition of the two antibodies.

Type II collagen-induced arthritis (CIA) in mice is an animal model of autoimmune inflammatory arthritis. Arthritis is induced in susceptible strains of mice (H-2q and H-2r) after immunization with heterologous or autologous type II collagen in CFA. Induction of CIA is T cell dependent and a restricted usage of TCR V beta genes has been found in the arthritic joints and lymph nodes of mice with CIA. However, genes within the MHC are not the only determinants of susceptibility to CIA as SWR/j, AU/ssJ (both H-2q) and RIIIS/J(H-2r) mice are resistant to the induction of CIA. These strains of mice are TCR V beta chain genes deletion mutants (TCR V beta a and TCR V beta c haplotypes) and it was hypothesized that these mice are resistant to CIA because of the absence of a particular set of V beta TCR genes that are genomically deleted in these strains of mice. We now show that BUB/BnJ mice (H-2q) are T cell subsets deficient because of the genomic deletion of TCR V beta 5, 8, 9, 11, 12, and 13 sub-families. Our data demonstrate that despite the deficiency in T cell subsets from genomic deletion of TCR V beta genes, BUB mice are highly susceptible to the development of CIA. These results indicate that genomic deletion of certain TCR V beta genes alone is not in itself sufficient to confer resistance to CIA. These results further suggest that other unknown gene(s) must also contribute to the induction of CIA.

Vasoactive intestinal peptide (VIP)-like immunoreactivity is present at low levels in the superior cervical ganglion of the adult rat, where immunostained neural processes, but only an occasional immunostained cell body, are found. However, when ganglia are maintained for 24 or 48 hr in organ culture, their content of VIP-like immunoreactivity increases 6- or 31-fold, respectively. When examined at 24 hr, the increase in VIP-like immunoreactivity is totally blocked by an inhibitor of RNA or protein synthesis. Many neuronal cell bodies and processes with immunoreactivity for VIP and the related peptide histidine isoleucine amide (PHI) are seen in cultured ganglia. In addition, VIP/PHI mRNA is abundant in cultured ganglia but only barely detectable in ganglia prior to culture. Under the same culture conditions, neuropeptide Y-like immunoreactivity increases to a small extent, and tyrosine hydroxylase activity and total ganglion protein remain unchanged. These results support the idea that adult sympathetic neurons exhibit plasticity in neuropeptide expression and that this plasticity, in the case of VIP, depends on changes in gene expression.