利用多媒体计算机对青年人根突的测量研究

目的 为计算机技术应用于全口义齿磨光面根突的制作提供测量方法和基础数据。方法 选择17～25岁青年人400例,灌取上、下颌模型,利用自行设计的多媒体计算机诊断与预测系统对根突形态进行测量。结果 得到根突形态的测量方法和基础数据。结论 根突形态有规律可循,测量值与上中切牙宽度相比,记录其相对值能科学地反映个体差异。

Effect of Jasmonic Acid on Lateral Root Formation in Rice Seedling

实验材料为水稻 (OryzasativaL .)栽培品种“IR8”(国际水稻所 8号 )及其少侧根突变体MT10。将 2d水稻幼苗种子根全部浸入 0 .0 16～ 5 0 μmol/L茉莉酸 (JA)溶液处理 2d ,结果表明JA显著抑制种子根的伸长 ,其抑制程度与JA浓度成正比。不高于 2 μmol/L的JA显著促进侧根的发生 ,每cm的侧根数目随浓度的增加而增加 ,最多可增加到原来的 16 8% (“IR8”)和 2 85 % (MT10 )。 10 μmol/L的JA仍促进处理过程中和处理后生成根区段的侧根数目的增加 ,但明显抑制处理前生成根区段侧根的发生 。

Preliminary study on a gravity－insensitive rice mutant

A gravity-insensitive mutant was isolated from rice (Oryza sativa L. cv. Zhonghua 11) transformed by Agrobacterium tumefaciens. The mutant's shoot growth (prostrate growth) was insensitive to gravity; whereas root growth displayed a normal positive gravitropism. Histological observation of root caps and leaf sheaths indicated that there was no significant difference in the number and size of amyloplasts in cells of the mutant and cells of the wild type.

Differential response of root morphology to potassium deficient stress among rice genotypes varying in potassium efficiency

Disparity in the root morphology of six rice(Oryza sativa L.) genotypes varying in potassium(K) efficiency was studied with three K levels:5 mg/L(low),10 mg/L(moderate) and 40 mg/L(adequate) in hydroponic culture. Morphological parameters included root length,surface area,volume and count of lateral roots,as well as fine(diameter<0.2 mm) and thick(diameter>0.2 mm) roots. The results indicate that the root growth of all genotypes was reduced under low K,but moderate K deficiency increased the root length of the efficient genotypes. At deficient and moderate K levels,all the efficient rice genotypes developed more fine roots(diameter<0.2 mm) than the inefficient ones. Both fine root count and root surface area were found to be the best parameters to portray K stress in rice. In accordance with the root morphology,higher K concentrations were noted in shoots of the efficient genotypes when grown at moderate and deficient K levels,indicating that root morphology parameters are involved in root uptake for K and in the translocation of K up to shoots. K deficiency affected not only the root morphology,but also the root ultra-structure. The roots of high-efficient genotypes had stronger tolerance to K deficient stress for root membrane damage,and could maintain the developed root architecture to adapt to the low K growth medium.

PAd-shRNA-PTN reduces pleiotrophin of pancreatic cancer cells and inhibits neurite outgrowth of DRG

AIM:To investigate the silencing effects of pAdshRNA-pleiotrophin(PTN) on PTN in pancreatic cancer cells,and to observe the inhibition of pAd-shRNA-PTN on neurite outgrowth from dorsal root ganglion(DRG) neurons in vitro.METHODS:PAd-shRNA-PTN was used to infect pancreatic cancer BxPC-3 cells;assays were conducted for knockdown of the PTN gene on the 0th,1st,3rd,5th,7th and 9th d after infection using immunocytochemistry,real-time quantitative polymerase chain reaction(PCR),and Western blotting analysis.The morphologic changes of cultured DRG neurons were observed by mono-culture of DRG neurons and co-culture with BXPC-3 cells in vitro.RESULTS:The real-time quantitative PCR showed that the inhibition rates of PTN mRNA expression in the BxPC-3 cells were 20%,80%,50% and 25% on the 1st,3rd,5th and 7th d after infection.Immunocytochemistry and Western blotting analysis also revealed the same tendency.In contrast to the control,the DRG neurons co-cultured with the infected BxPC-3 cells shrunk;the number and length of neurites were significantly decreased.CONCLUSION:Efficient and specific knockdown of PTN in pancreatic cancer cells and the reduction in PTN expression resulted in the inhibition of neurite outgrowth from DRG neurons.

Sinorhizobium meliloti nifA mutant induces different gene expression profile from wild type in Alfalfa nodules

Several studies have demonstrated that the Rhizobium nifA gene is an activator of nitrogen fixation acting in nodule bacteria. To understand the effects of the Sinorhizobium meliloti nifA gene on Alfalfa, the cDNA-AFLP technique was employed to study the changes in gene expression in nifA mutant nodules. Among the approximately 3,000 transcriptderived fragments, 37 had differential expression levels. These expression levels were subsequently confirmed by reverse Northern blot and RT-polymerase chain reaction. Sequence analyses revealed that 21 cDNA fragments corresponded to genes involved in signal communication, protein degradation, nutrient metabolism, cell growth and development.

Antiretroviral Therapy through Barriers： A Prominent Role for Nanotechnology in HIV-1 Eradication from Sanctuaries

Abstract： In HIV-1 management, eradication of the virus from sanctuaries represents a major and challenging goal. The genital tract, gut associated lymphoid tissue, lymph nodes, central nervous system, macrophages and latently infected CD4＋ T lymphocytes are typical sites where H1V-1 compartmentalizes. To circumvent this problem, a consistent number of studies have focused on improving ARVs （antiretroviral drugs） delivery into sanctuary sites and different nanoteehnological approaches have been developed. Cellular HIV-1 sanctuaries （i.e. macrophages） can be reached by nanoformulation of ARVs or by activation of latently infected cells. Anatomical sanctuaries （i.e. brain or male genital tract） can be addressed by increasing the permeation of ARVs across tissue barriers, such as the blood-brain barrier or the blood-testis barrier, while ARVs concentration in lymph nodes can be enhanced by drug encapsulation in CD4-targeted nanoparticles.

Is There Hysteresis in Unemployment in OECD Countries？ Evidence From Panel Unit Root Test With Structural Breaks

This study tests the hysteresis hypothesis of unemployment in fifteen OECD countries by using panel unit root tests which allow for structural breaks. We apply annual unemployment rates covering 1985-2008 periods. We test whether unemployment rates are stationary by using second generation tests which allow cross section dependency among series and panel unit root test based on structural break advanced by Carrion-i-Silvestre, Barrio-Castro and Lopez-Bazo （2005）. We find series as a stationary process with structural breaks according to Carrion-i Silvestre et al. （2005） test, while we find series as unit root process with second generation panel unit root test. According to the Carrion-i Silvestre et al. （2005） test, we find the evidence of absence of hysteresis in analyzed countries. As a result, temporary shocks have temporary effects on unemployment instead of permanent effect. Structural factors can affect the natural rate of unemployment and, therefore, unemployment would be stationary around a process that is subject to structural breaks. So, there still exists a unique natural rate of unemployment to which the economy eventually will converge.

A gene encoding AtPIP5K2 may be involved in regulating the sensitivity to osmotic stress

One mutant line eto with salt tolerance was screened from a T-DNA insertion mutant collection of Arabidopsis thaliana. In addition to a reduced rate of seed germination, NaCl and ABA also inhibited the growth and the greening of cotyledons of wild-type seedlings, but not the eto mutant. TAIL-PCR analysis showed that T-DNA tag insertion in the eto was located at nucleotide 27,502 in BAC F3M18, upstream （at position -487 relative to the translation initiation codon） of gene At lg77740 （encoding a putative phosphatidylinositol-4-phosphate 5-kinase, AtPIP5K2）. This inserted mutation cosegregated closely with the eto phenotype, Another analysis not only indicated that AtPIP5K2 transcript is expressed predominantly in roots and rosette leaves, but also showed the T-DNA insertion resulted higher accumulation of the AtPIP5K2 in eto mutant plants and did not influenced the expression of the upstream At lg77730 gene. This change may play an essential role in the tolerance of eto mutant plant to the osmotic stress.

Expression of the tyrosine kinase receptor EphA5 and its ligand ephrin-A5 during mouse spinal cord development

Objectives To study the expression patterns of two Eph family molecules, the receptor EphA5, and the ligand ephrin-A5, during spinal cord development. Methods The receptor expression was analyzed using beta-galactosidase knockin mice, and affinity ligand probe binding. The ligand expression was assessed using two different affinity probes, and knockout mouse tissues as controls. Results EphA5 was expressed in the ventral spinal cord, while ephrin-A5 was located in the dorsolateral regions of the spinal cord throughout development. Conclusions These results show that EphA5 and ephrin-A5 are expressed over broad developmental stages and may play important roles in establishing the dorsoventral organization of the spinal cord.

孤立性翼突良性病变的诊断与治疗

目的：探讨孤立性翼突良性病变的临床和病理特征,以及经鼻内镜手术治疗和转归特点。方法：回顾性分析我科收治的4例翼突良性病变患者的临床资料。术前均行高分辨率CT及增强MRI检查,全身麻醉,经鼻内镜行肿物切除手术。术后随访12-48个月,行鼻内镜及MRI检查,了解术腔恢复情况及术后复发情况及手术前后症状改变及缓解情况。结果：术后病理确诊,2例为囊肿性病变,1例为梭形细胞脂肪瘤,1例为炎性病变。术后随访术腔瘢痕形成,表面光滑,术后无复发,术后未有新发症状,术后鼻塞缓解,头痛症状无变化。结论：高分别率CT结合增强MRI对于翼突部位病变的位置、范围、性质的确定有重要意义。经鼻内镜切除孤立性翼突良性病变是一种微创、安全、有效的治疗方法。