mlsa-iai-msu-lab/ru_sci_bench_zho_cite_reranking huggingface dataset:
Construction of phospholamban antisense RNA recombinant adeno-associated virus vector and its effects in rat cardiomyo-cytes

To construct a recombinant adeno-associated virus (rAAV) vector containing gene encoding phospholamban antisense RNA (asPLB), and analyse its effect on expression of PLB, expression and activity of sarco-endoplasmic reticulum Ca2+-ATPase (SERCA), and the change of intracellular free Ca2+ concentration ([Ca2+]i) in rat cardiomyocytes. Methods: The target gene encoding PLB antisense RNA was inserted inversely into the adeno-associated virus plasmid pAAV-MCS digested by corresponding restricted endonuclease enzyme. The recombinant plasmid and pAAV-RC and pHelper were co-transfected into 293 cell. At the same time, a viral production positive control (rAAV-LacZ) and negative control were performed. The recombinant viruses were used to transfect the cultured rat cardiomyocytes. Site β-Galactosidase staining were performed to observe the transfer efficiency. Reverse transcription-PCR and Western blot were used to determine the mRNA and protein expression of PLB and SERCA. The activity of SERCA and the [Ca2+]i were measured. Results: The rAAV vectors were constructed successfully and were transfected into rat cardiomyocytes effectively. The PLB mRNA and protein expression were reduced in rat cardiomyocytes transfected by rAAV-asPLB compared with controls. The activity of SERCA was increased. In rest state, the level of [Ca2+]i in the rAAV-asPLB transfected group decreased. The level of [Ca2+]i increased when induced by isoproterenol. Conclusion: AAV-asPLB vector was constructed successfully, which disrupted the expression of PLB, enhanced the activity of SERCA, reduced the resting [Ca2+]i, and improved the cardiac function.
NECESSITY AND METHOD OF PUBLIC PARTICIPATION IN STRATEGIC ENVIRONMENTAL ASSESSMENT OF CHINA

Public participation has been one of important problems in the strategic environmental assessment(SEA). In this paper, the origin and the present research-conditions of public participation in SEA were analyzed. Andthe necessity of public participation was illuminated from following three aspects: 1) the public participation in Chi-na's SEA is a key method of gaining the public support; 2) the public participation is one important source of gaininginformation; 3) the public participation is a good way to overcome the obstruction in the traditional mechanism of mak-ing strategy decision. Effective public participation should be involved in the whole process of SEA, and the public par-ticipators should include the public representatives of the groups affected by environmental change, the specialists inSEA and relevant fields, persons who are interested in the strategy and media, and so on. Various methods of public par-ticipation in SEA, including the methods of obtaining information and information feedback or consultation, were dis-cussed. Further, the function, the advantages and the disadvantages of each method were discussed in detail, too.
Spatial Variation of P and N in Water and Sediments of Dianchi Lake, China

Dianchi Lake is one of the most eutrophic lakes in China. In order to understand this eutrophication and to help control the pollution, this research investigated the spatial distribution of Kjeldahl nitrogen (K-N) and total phosphorus(TP) through analysis of bottom water and sediment (3 depths) samples collected at 118 sites around Dianchi Lake. The concentrations of K-N and TP for the lake bottom water in the Caohai part of the lake were much higher than those in the Waihai part, generally decreasing from north to south. In the sediments, the K-N concentration was higher in the Caohai part and the middle of the Waihai part. On the other hand, TP in the sediments was greater in the southern and western parts. Both K-N and TP had similar spatial distributions for the sediment samples of three different depths.Vertically, the K-N and TP concentration in the sediments decreased with an increase in depth. This was evidence that eutrophication and pollution of Dianchi Lake was becoming gradually more severe. Exterior factors including uncontrolled input of domestic and industrial effluents as well as non-point pollution around the lake were the main reasons for serious eutrophication; therefore, controlling these was the first step in reducing eutrophication of Dianchi Lake.
Ammonia Volatilization Losses from Urea Applied to Wheat on a Paddy Soil in Taihu Region, China

Ammonia volatilization losses from urea applied as a basal fertilizer and a top dressing at tillering stage in a wheat field of Taihu Region, China, were measured with a micrometeorological technique. Urea as fertilizer was surface broadcast at 81 (low N) and 135 (high N) kg N ha-1 as basal at the 3-leaf stage of the wheat seedling on December 2002, and 54(low N) and 90 (high N) kg N ha-1 as top dressing on February 2003. Ammonia volatilization losses occurred mainly in the first week after applying N fertilizer and mainly during the period after basal fertilizer application, which accounted for more than 80% of the total ammonia volatilization over the entire wheat growth period. Regression analysis showed that ammonia volatilization was affected mainly by pH and NH4+-N concentration of the surface soil and air temperature.Ammonia volatilization flux was significantly correlated with pH and NH4+-N concentration of the surface soil and with daily air average temperature and highest temperature. Thus, application of urea N fertilizer to wheat should consider the characteristics of ammonia volatilization in different periods of N application so as to reduce ammonia losses.
Antiapoptotic effect both in vivo and in vitro of A20 gene when transfected into rat hippocampal neurons

To evaluate the antiapoptotic effect of the A20 gene in primary hippocampal neurons both in vivo and in vitro. Methods: Primary hippocampal neurons in embryonic day 18 (E18) rats were transfected with the A20 gene by using the new Nucleofector electroporation transfection method. We then examined, whether A20 -neurons possessed anti-apoptotic abilities after TNF-α stimulation in vitro. A20-neurons and pcDNA3 -neurons were transplanted into the penumbra of the brains of rats that had been subjected to 90-min of ischemia induced by left middle cerebral artery occlusion (MCAO). Results: A20-neurons resisted TNF-α induced apoptosis in vitro. The apoptosis rate of neurons overexpressing A20 (28.46%±3.87%) was lower than that in neurons transfected with pcDNA3 (53.06%±5.36%). More A20-neurons survived in the penumbra both 3-d and 7-d after transplantation than did sham pcDNA3 neurons. Conclusion: The novel function of A20 may make it a potential targets for the gene therapy for neurological diseases.
Soil Phosphorus Dynamics as Influenced by Land Use Changes in Humid Tropical, Southwest China

Land use changes can greatly influence soil phosphorus (P) dynamics, especially when converting native forests to agricultural land. Soils in Xishuangbanna, which is one of southwest China's tropical areas that maintain fragments of primary forests, were studied to a) evaluate the effect of two common land use changes, conversion of forests to agricultural land or rubber tree plantation, on the dynamics of available P and total P in bulk soils as well as total P in particle size fractions; b) assess the relationship between soil P dynamics and soil organic carbon (SOC); and c)elucidate the relationship between soil P content and soil properties such as pH and texture. Clearing secondary forests with subsequent shifting cultivation and establishment of rubber tree plantation caused significant decreases (P ＜ 0.05)in available P at 0-20 cm soil depths, whereas for total P there was a significant decrease (P ＜ 0.05) when converting to shifting cultivation, rubber tree plantation, or fallow field at both 0-20 and 20-40 cm depths. Abandonment of fields used for shifting cultivation led to significant increases (P ＜ 0.05) in available P at 20-40 cm depth. In addition, there was a significant positive relationship between soil organic carbon and soil P content. Compared to secondary forests, the ratio of organic carbon to total P in surface soils (0-20 cm) of shifting cultivation and rubber tree plantation was significantly lower (P ＜ 0.05).
白菜WRKY转录因子cDNA片段的克隆

WRKY转录因子是一类含有WRKY氨基酸的锌指蛋白,到目前为止,仅在植物中被发现(Yu et al.,2001).WRKY蛋白含有1个或2个十分保守的WRKY区域,但在保守区域外基因间的同源性较低(Chen and Chen,2002).本研究参照拟南芥WRKY转录因子保守序列设计简并引物,通过RT-PCR方法获得白菜WRKY转录因子cDNA序列,为克隆该转录因子全长cDNA提供基本资料.……
高产抗倒小麦新品种皖麦50及其栽培技术

皖麦50(宿9908)是宿州市农科所1994年用丰产性好、秆矮、抗倒、早熟、落黄较差的豫麦29作母本,以丰产稳产、综合抗性好,适应性广,中后期耐旱、秆高、抗倒能力差的皖麦19为父本进行有性杂交,获得结合双系优点的超亲类型,育出高产、高抗倒伏、中熟、中后期耐旱,抗病和易栽培的小麦新品种.后代采用系谱法选育,杂种F2、F3代分离较大,着重穗多、矮秆、抗病、落黄好等基因性状的选择;F4到F6代性状趋于稳定,着重抗倒、抗旱耐旱性、株型、产量潜力、籽粒品质等基因性状的选择,确定综合性状好的基因类型.1999年后代品系稳定出圃.于2004年2月经安徽省品种审定委员会审定并命名.
噬菌体裂解法快速检测结核分枝杆菌

我们自2003年1月起采用结核分枝杆菌噬菌体裂解法快速检测肺结核患者痰液标本中的结核分枝杆菌,结果报告如下.　　1 材料和方法　　1.1 材料结核分枝杆菌噬菌体裂解法试剂盒(FASTPlauqetbTM)购自英国Biotec公司,批号:AC9002.
Extraction and Characterization of Humic Acids and Humin Fractions from a Black Soil of China

Twenty-three progressive extractions were performed to study individual humic acids (Has) and humin fractions from a typical black soil (Mollisol) in Heilongjiang Province, China using elemental analysis and spectroscopic techniques. After 23 HA extractions the residue was separated into high and low organic carbon humin fractions. HA yield was the highest for the first extraction and then gradually decreased with further extractions. Organic carbon (OC) of the humin fractions accounted for 58％ of total OC even after 23 successive HA extractions. In addition, the atomic C/H ratio decreased during the course of extraction while C/O increased; the E4/E6 ratio from the UV analysis decreased with further extraction while E2/Ea increased; the band assigned to aliphatic carbon (2 930 cm-1) in the diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) spectra gradually increased with progressive extraction; the calculated ratio of the sum of aromatic carbon peak heights to that of aliphatic carbon peak heights from DRIFTS spectra declined with extractions; and nuclear magnetic resonance (NMR) data suggested that HA aliphatic carbons increased with extractions while aromatic carbons decreased. Thus, hydrophobicity and aliphaticity of Has increased with extractions while polarity and aromaticity decreased. These data showed substantial chemical, structural, and molecular differences among the 23 Has and two humin fractions. Therefore, these results may help explain why soil and sediment humin fractions have high sorption capacity for organic contaminants.
快速悬浮床烟气脱硫

对快速悬浮烟气脱硫的脱硫特性进行了研究,分析了钙硫比、趋近绝热饱和温度、烟气在吸收塔内的流速以及石灰浆滴的粒径大小和分布等因素对该工艺脱硫效率的影响.结果表明,对系统脱硫效率影响最为明显的参数是脱硫塔出口的趋近绝热饱和温度和钙硫比.得出了最佳的温差为10℃,最佳钙硫比为1.5.
Streptomyces avermitilis from marine

The insecticidal strain 173 was isolated from marine source and its activity was explored by the bioassay of brine shrimp and Helicoverpa armigera. Based on morphological, physiological and molecular properties, the insecticidal strain 173 was identified as Streptonycetes avermitilis, which is the best insecticidal microorganism found in the terrestrial environment. The taxonomy of the strain173, insecticidal spectrum and properties of the corresponding insecticidal antibiotics are reported.
Levels of polychlorinated biphenyls in 1,4-dichlorobenzene mothballs

Although polychlorinated biphenyls(PCBs) are globally recognized pollutant, an understanding of their resources as by-products in chemical industry is poorly investigated. This paper presents data from a study that was conducted in order to determine the extent of PCBs in 1,4-dichlorobenzene(p-DCB) mothballs. Total PCBs and dioxin-like PCBs were detected in five mothball samples. Total PCB concentrations ranged from 328 ng/g to 1798 ng/g, while the levels of WHO-TEQ were between 0.16 pg/g and 13 pg/g. Mean concentrations of total PCBs and WHO-TEQ in the samples were 724 ng/g and 3.2 pg/g, respectively. The highest level of PCB congeners was that of trichlorinated biphenyls(537 ng/g), which maybe due to the relatively low chlorination in the process of p-DCB production. A mechanism of the formation of PCBs from polychlorinated benzene in the presence of chlorine is also suggested. The results suggested that re-estimation on the risk of p-DCB products, especially the products for daily use such as mothballs, is expected.
Growth of Aligned Carbon Nanotubes through Microwave Plasma Chemical Vapor Deposition

Aligned carbon nanotubes (CNTs) were synthesized on glass by microwave plasma chemical vapor deposition (MWPCVD) with a mixture of methane and hydrogen gases at the low temperature of 550 ℃. The experimental results show that both the self-bias potential and the density of the catalyst particles are responsible for the alignment of CNTs. When the catalyst particle density is high enough, strong interactions among the CNTs can inhibit CNTs from growing randomly and result in parallel alignment.
Effect of free-air CO2 enrichment on nematode communities in a Chinese farmland ecosystem

At a rice-wheat rotational free-air CO2 enrichment(FACE) platform, the effect of elevated atmospheric CO2 on soil nematode communities in a farmland ecosystem was studied. Wheat plots were exposed to elevated atmospheric CO2 (ambient 370 μl/L + 200 μl/L).32 families and 40 genera of nematode were observed in soil suspensions during the study period. Under FACE treatment, the numbers of total nematodes, bacterivores and fungivores exhibited an increasing trend. Because of the seasonal variation of soil temperature and moisture, the effectof elevated atmospheric CO2 on soil nematodes was only observed under favorable conditions. The response of nematode communities to elevated atmospheric CO2 may indicate the change of soil food web.
Investigation of natural VOC emitted from tropical vegetations in China

Twenty-three kinds of typical plants in Xishuangbanna, the tropical area of southwestern China, were screened to estimate the emission rates of isoprene and monoterpenes by adopting bag-enclosure and curette sampling methods followed by a GC-FID analysis. It was found that the Ficus species were mainly emitting isoprene and most tropical vegetations were mainly releasing monoterpenes. The results also showed that the emissions of isoprene were affected by both temperature and PAR( Photosynthetic Active Radiation), while monoterpene emissions were mainly temperature-dependent.
Organic carbon stock in topsoil of Jiangsu Province, China, and the recent trend of carbon sequestration

Data collection of soil organic carbon(SOC) of 154 soil series of Jiangsu, China from the second provincial soil survey and of recent changes in SOC from a number of field pilot experiments across the province were collected. Statistical analysis of SOC contents and soil properties related to organic carbon storage were performed. The provincial total topsoil SOC stock was estimated to be 0.1 Pg with an extended pool of 0.4 Pg taking soil depth of 1 m, being relatively small compared to its total land area of 101700 km2 . One quarter of this topsoil stock was found in the soils of the Taihu Lake region that occupied 1/6 of the provincial arable area. Paddy soils accounted for over 50% of this stock in terms of SOC distribution among the soil types in the province. Experimental data from experimental farms widely distributed in the province showed that SOC storage increased consistently over the last 20 years despite a previously reported decreasing tendency during the period between 1950-1970. The evidence indicated that agricultural management practices such as irrigation, straw return and rotation of upland crops with rice or wheat crops contributed significantly to the increase in SOC storage. The annual carbon sequestration rate in the soils was in the range of 0.3-3.5 tC/( hm2 · a), depending on cropping systems and other agricultural practices. Thus, the agricultural production in the province, despite the high input, could serve as one of the practical methods to mitigate the increasing air CO2.
紫杉醇联合5-氟脲嘧啶、顺铂治疗晚期胃癌、食管癌38例疗效评价

紫杉醇(PTX)是从红豆杉树皮中提取的广谱抗肿瘤药物,其抗癌作用机制主要是通过促进微管蛋白装配成微管及阻滞其解聚,从而使细胞的微管失去正常功能,导致癌细胞死亡[1].2001年6月至2003年12月,作者采用国产紫杉醇(PTX,北京四环制药厂,批号:0309231)联合顺铂(DDP)以及5-氟脲嘧啶(5-Fu)治疗晚期食管癌以及胃癌患者38例,临床疗效较好,报道如下.
吗啡耐药性及依赖性的细胞分子生物学机制研究近况

自1806年Sertürner报道从鸦片里分离出吗啡至今已近200年,吗啡仍然被有效地广泛应用于临床治疗各种急慢性疼痛.但是由于存在耐药性及依赖性而使其应用受到限制,并且滥用吗啡及其衍生物仍然是非常深刻的社会问题.所以伴随着吗啡的诞生,人们就致力于其耐药性及依赖性的研究.尽管有可观的进步,但有关介导其发生的分子及细胞学机制仍然不清楚或存在争论.本文就吗啡耐药及依赖性发生机制中细胞信号转导及神经适应性塑性方面近年研究的概况作一简要介绍.
Preventive role of palladium-103 radioactive stent on in-stent restenosis in rabbit iliac arteries

The abilility of γ-emitting palladium-103 stent implantation to inhibit in-stent restenosis in rabbit iliac arteries was investigated. Quantitative histomorphometry of the stented iliac segments 28 days after the implantation indicated that palladium-103 stents made a significant reduction in neointimal area and percent area stenosis compared with the nonradioactive stents. Lumen area in the palladium-103 stents treatment group was larger than the control group. However, the reduction of neointima formation by palladium-103 stents implantation was in a non-dose-dependent fashion. Low ionizing radiation doses via γ-emitting palladiurn-103 stent are effective in preventing neointimal hyperplasia in iliac arteries of rabbits. Palladium-103 stents can be employed as a possible novel means to prevent in-stent restenosis.
骨髓间充质干细胞移植治疗脑梗死的研究现状

从传统的发生生物学观点来看,成年受损伤大脑不具备结构上有意义的自身修复功能,成熟脑细胞一旦受损就不能再生.骨髓间充质干细胞(mesenchymal stem cells,MSCs),又称骨髓基质干细胞,是骨髓中非造血实质细胞的干细胞,具有高度的自我复制能力和多向分化潜能,可分化成多种细胞.传统观点认为,MSCs只能够分化成中胚层来源的间质细胞,如:成骨细胞、软骨细胞、脂肪细胞、肌腱细胞、网状细胞和血管内皮细胞,但近来研究表明它可以向三个胚层的多种组织分化,如来源于外胚层的神经元、神经胶质细胞等,故MSCs近年来被用于脑缺血动物模型的治疗,初步研究表明它能改善脑缺血动物的神经功能缺失症状,MSCs移植为脑缺血患者开辟了一种新的治疗方法.本文对MSCs移植治疗脑缺血的研究近况进行综述.
脊髓马尾神经内恶性淋巴瘤1例

患者女性，68岁。双下肢进行性麻木、疼痛、无力，运动障碍2个月。病情发展较快，下肢逐渐瘫痪。查体：全身浅表淋巴结不肿大。腹部B超示肝、胆、胰、脾、肾未见明显异常。MRI示腰椎管内（L1～S4）占位病变。手术探查腰2、3、4椎管内马尾神经较正常粗大，与周围神经粘连。游离时见每根神经变粗，质地较硬。
Theorems of Idempotent Commutative Groupoids

In this paper, among other results, we prove that a clone C with five essentially binary operations is minimal if and only if C is a clone of a non-trivial affine space over GF(7).   This result is a product of systematic investigation of varieties of idempotent commutative groupoids.  It is probably the most spectacular result of this investigation, but many other results formulated and proved throughout the paper may turn out more useful in further study in this area.
Effects of AlN Layer and Impurities on Optical Properties of GaN

The effects of the incorporated oxygen and the different buffer layers on the optical properties and surface morphology of GaN were studied. The results show that the decrease of the concentration of the incorporated oxygen has no effect on the surface morphology, but improves the optical properties. While the introduction of the AlN buffer layer makes not only the surface morphology but also the optical properties improve. Both the oxygen contamination from the nitrogen source and the resulted morphology are directly related to the line width of the low-temperature photoluminescence(PL) spectra.
1例医疗事故鉴定的分析探讨

杨某,女,46岁.无意中发现颈部肿物并疼痛4个月,于2002年5月6日就医.查体:颈部向右偏斜,活动自如;右颈部触及约7cm×5cm×5cm大小的圆形肿块,其边界清楚,质地硬,有压痛,并随吞咽动作上下移动;皮肤正常.5月30日核素扫描图提示:结节性甲状腺肿大(右叶"凉结节",峡部"热"结节).
基于包络线法对土壤光谱特征的提取及其分析

土壤的光谱反射率是土壤内在的理化特征之光谱行为的综合反应[1].Stoner[2]比较详细地描述了五大类土壤光谱反射曲线类型及其与土壤性质、土壤发生分类的关系.戴昌达等[3]根据360～2 500nm的土壤光谱反射率,将我国主要土壤的光谱反射特性曲线划分为平直型、缓斜型、陡坎型和波浪型四类.
蛋白酪氨酸磷酸酶IB与亚型糖尿病的中药治疗

蛋白酪氨酸磷酸酶IB（PTPIB）是II型糖尿病相关蛋白，是治疗II型糖尿病一个重要的潜在靶点。II型糖尿病的治疗关键是要寻到对PTPIB具有高度选择性的有效抑制剂。目前，有一些关于PTPIB抑制剂的文献报道，但这些抑制剂对PTPIB的选择力不够强。中药中有很多单味中药和复方制剂有降血糖作用，但其治疗糖尿病的作用机制还不很清楚，可能是中药制剂中的某个或某些成分与机体中PTPIB或其他糖尿病相关蛋白发生了作用等。开展药效学和基因芯片研究有利于深人探讨中药治疗正型糖尿病的作用机制。
腹腔镜术后趋肤效应致迟发性消化道穿孔一例

患儿:男,80 d.因发热2d伴腹泻入内科.入院前8 d曾于我院行腹腔镜下幽门环肌切开术,术后第2 d开始饮食,无呕吐、发热等症状,第6 d出院.出院当天发热,因有明确呼吸道感染接触史、症状和体征,考虑合并肺炎,家长亦要求当地治疗,遂出院.出院后持续发热,后出现发吭、腹胀,2 d后再次入院.入院查体:T:38.5 ℃,P:130次/min, R:42次/min,神清、颈软、反应差,双肺呼吸音粗,可闻干湿啰音,腹稍胀,软,无明显腹膜炎体征,肠鸣音存在,但较弱,1～2次/min.X线片示:肺部散在斑片影,肠管气体分布不均,结合病史考虑肺炎、肠功能紊乱,收入内科.次日病情加重,腹胀明显,复查X线片示:膈下有游离气体,急转外科手术.术中见幽门黏膜有一0.2 cm×0.2 cm的穿孔,予修补.术后消炎对症支持治疗,痊愈出院.术后诊断:腹腔镜下幽门环肌切开术后迟发性幽门穿孔;泛发性腹膜炎;肺炎.
HPLC法测定栽培芍药枯萎前后不同部位芍药昔的含量变化

白芍为芍药科植物芍药Paeonia lactifloraPall. 的干燥根。白芍具有养血柔肝、缓中止痛、敛阴止汗的作用，其临床应用十分广泛。白芍的主要化学成分是以芍药昔（poeoniflorin）为代表的单枯及其昔类化合物。关于芍药中芍药昔的含量测定已有很多报道〔1-3〕。本实验以HPLC法对芍药根不同部位及枯萎前后芍药昔的含量进行测定，分析其含量变化，为芍药的采收加工的合理化提供依据。
婴幼儿血管瘤的起源及其病理演变机制

婴幼儿血管瘤是儿童期最常见的肿瘤,在白种人儿童中的发病率高达8%～10%[1],好发于头面部,在开始6个月中,增长非常迅速,此后,增长速度逐渐减慢,到1岁左右,开始进入消退期[2].……
用于CNC系统的新型液晶驱动系统的开发

主要介绍在新型数控系统(CNC)研发过程中LCD硬件连接及驱动程序的开发.新型数控系统使用LH79520 CPU,该CPU内置的彩色液晶控制器驱动LM32019T液晶屏.
车床主轴箱前轴承孔变形的原因分析

普通车床在静态下测试,其几何精度合格,主轴径向跳动、轴向窜动不超差,但加工轴类零件时产生锥度较大.文章从主轴箱体的材料、成型工艺和主切削力作用下引起前轴承孔的塑性变形进行了全面的分析,并提出了维修方案,对金属切削机床故障判断具有一定的指导意义.
机械制造企业信息化讲座:第七讲企业经营管理与ERP技术

1企业经营管理与ERP技术的发展1.1从定货点法到MRP20世纪60年代以前企业生产管理采用库存控制法,也称为定货点法.60年代美国管理专家约瑟夫·奥列基提出对物料的需求有独立需求与相关需求两种类型的概念后,产生了解决物料需求的新思想.将独立需求和相关需求分别加以处理,其次在库存状态中引入了时间分段的概念.所谓时间分段就是给库存状态数据加上时间坐标,亦即按具体的日期计划时区记录和存贮状态数据,从而解决了何时定货以及订货的数量问题.这就是物料需求计划(MRP:Material Re-quirement Planning).
视网膜干细胞研究现状

干细胞是当今细胞生物学乃至整个生命科学研究的主要热点之一,视网膜干细胞的研究近年来颇有进展,这对于治疗眼科临床的一些疾病,如遗传性视网膜变性、原发或继发性视网膜变性疾病、老年性黄斑病变等,提供了具有较大发展潜力的新途径.现就视网膜干细胞的发现与鉴定,体外培养、增殖、分化以及移植方面的研究进展作一综述.
数控车床液压卡盘软爪车削夹具

数控车床一般用液压卡盘来夹持工件.液压卡盘通常都配有不淬火的卡爪,我们称之为软爪.软爪分为内夹和外夹两种形式,卡盘闭合时夹紧工件的软爪为内夹式软爪,卡盘张开时撑紧工件的软爪为外夹式软爪.如图1所示,软爪1是以端面齿槽与卡爪座3定位,通过螺钉和卡爪座中的T型螺母2固定在卡爪座3上.液压卡盘工作时,软爪在卡爪座的带动下,作闭合或张开运动,将工件夹紧或松开.夹持不同工件时,通过改变软爪在卡爪座上的位置来改变液压卡盘的夹持尺寸.
提高机床制造企业的核心竞争力--专访中国机床工具工业协会总干事长吴柏林先生

2004年中国政府为了保障国民经济的健康协调发展,对一些领域实行宏观调控.这种宏观调控对中国机床市场产生了哪些影响?CIMT2005展览会在即,展会情况如何?面对国家的宏观调控政策,以及国外机床制造商的极大压力,中国机床工具行业如何应对?带着这些疑问,我刊记者专门拜访了新当选的中国机床工具工业协会总干事长吴柏林先生,我们一起来听听吴总干事长先生的观点.
钻顶结合施工法在导流排水管施工中的应用

耒阳电厂灰坝四口辐射井沉井最深达33 m,每口井间距60 m,井间的φ127导流钢管施工难度大.根据现场的地质情况,采用自行设计的"钻顶结合"的施工工艺.首先采用顶管顶进25～35 m,换钻机用钻杆从顶管中穿过后再钻进25～35 m,进行纠偏到达井壁,最后换顶管机沿着钻杆顶进到井壁,较好地解决了这一难题.
城镇污水生物脱氮达标排放工艺选择

《城镇污水处理厂污染物排放标准》(GB18918-2002)中规定了新的氮排放标准.通常污水处理厂采用生物脱氮处理工艺时,出水中氮含量远低于规定值,为此,提出了生物脱氮处理工艺出水水质恰好达标的几种工艺,以节约投资与运行费用.
硒有效防治病毒感染性疾病进展

人体必需的微量元素硒与病毒感染性疾病关系的新研究成果日益增多.本文将以大量实验和临床研究成果,结合病毒感染的共性特征,对硒通过提高机体免疫力和适宜的氧化还原调控能力来降低人体对病毒感染的易感性,有效防治病毒感染性疾病做一综述.提示硒用于各种病毒传染性疾病防治的重要意义.
亲子鉴定中检出21三体综合征一例

我们在亲子鉴定案例中检出1例21三体综合征(Down's syndrome),其3个位于21号染色体的短串联重复序列(short tandem repeat, STR)基因座图谱均表现为3个峰(或3条带),现报道如下.……
充分利用冬闲稻田大力发展冬季饲草

论述了小黑麦、黑麦草、鲁梅克斯、紫云英等冬季饲草在湘南冬闲稻田的发展前景、产量、营养价值及栽培技术.实践表明:湘南地区利用冬闲稻田种植小黑麦、黑麦草、鲁梅克斯、紫云英等冬季饲草可以解决牛、羊等草食动物在冬季和早春桔草季节没有青草供应的矛盾,保证牧草四季均衡供应,为湘南发展草食动物创造有利条件.
红壤母质熟化过程中土壤磷的组分变化研究

通过对3种红壤母质和不同施肥管理条件下土壤磷组分的分析,发现在花岗岩母质中,O-P是无机磷的主要组成部分,紫色土母质以Ca10-P为主,四纪红壤以O-P为主.不施用化学肥料,由于红壤母质肥力低下,作物产量很低,对土壤熟化的影响很小,土壤组分变化很少.施用化学肥料(含化学磷肥)后,3种母质的Ca-P、Al-P、Fe-P明显上升,土壤有效磷和全磷都显著增加.施用化学磷肥使土壤对磷的吸附减少,提高磷肥当季作物利用率.施肥是加速红壤母质熟化的主要途径和方法.
土壤对铵的矿物固定及固定态铵释放的研究进展

概述了近年来国内外学者在土壤对铵的矿物固定与土壤固定态铵的释放研究方面的进展情况,包括土壤固定态铵的含量、土壤对铵的矿物固定机制、土壤对铵的矿物固定及其释放的动力学与其影响因素,并对今后的进一步研究进行了展望.
湖南省柑桔种植中存在的问题及对策

分析了湖南省柑桔栽培种植中存在的主要问题,提出湖南柑桔产业的发展必须更新观念、加强协作、实现生产良种化、优质化、高效化、安全化、产业化,建立大市场,树立大品牌.
水稻理想株型研究进展与育种策略

从穗、叶、根、株高等方面简要介绍了株型育种所取得的进展和育种专家提出的几个有代表性的理想株型模式,指出了21世纪中国水稻育种工作者应坚持理想株型与优势利用相结合的方向,坚持常规技术与高新技术的联结,坚持跨地域、跨学科、跨专业的强强联手的水稻理想株型育种策略.
染色体t(11;15)平衡易位

先证者男,2天,因其母患妊高症,孕35+5周,行剖宫产,出生体重2200 g.查体:头颅正常,五官端正,眼、耳鼻无异常,腹软,肝脾不大,肛门正常,阴茎短小,隐睾,上肢,左手掌外翻,右脚内翻,神经系统无阳性发现,患儿患新生儿呼吸窘迫综合征.其母,28岁,系第1次妊娠,孕期无感冒及服药史,无有毒有害物接触史,其父母非近亲结婚,身体均健康.
逆行岛状皮瓣临床应用失败原因分析及技术改进

目的分析逆行岛状皮瓣临床应用失败的原因并提出改进的方法. 方法 1994年7月至2003年5月,临床应用逆行岛状皮瓣160例.对其中15例手术失败者进行了分析. 结果静脉回流障碍是引起逆行岛状皮瓣手术失败的主要原因(9例),其中,皮瓣完全坏死5例,皮瓣远端部分坏死4例;皮瓣的蒂部扭转或受压是术后皮瓣坏死的另一重要原因(3例). 结论吻合皮瓣远端浅静脉可改善逆行皮瓣的静脉回流,切断并结扎皮瓣蒂部浅静脉是手术成功的关键.仅依靠逆行岛状皮瓣蒂部的两条伴行静脉能够保证皮瓣的静脉回流.
病毒性角膜内皮炎临床观察

我院自2001-2003年收治了7例病毒性角膜内皮炎患者并取得较好的疗效，现将诊治情况总结如下： 临床资料：7例患者均为单眼发病，其中右眼2例，左眼5例；男4例，女3例；年龄最大43岁，最小18岁，平均为26岁。5名患者既往有病毒性角膜炎的病史并在门诊或入院治疗。本次发病诱因：‘上感，3例，疲劳2例，月经1例，焦虑1例。本次发病至就诊时最短2天，最长5天，期间均未用激素治疗。入院查体：视力0.08-0.1之间5人，0.2-0.3之间2人，结膜混合充血，角膜上皮层光滑，基质层水肿，病变区角膜增厚，未见明显灰白混浊浸润及新生血管。水肿区见后弹力层皱褶，内皮层混浊、粗糙，KP为色素性和／或灰白点状并局限于水肿区。其中3人房闪＋，未见成形渗出，瞳孔3x3mm，直接光反射灵敏。其中6人眼压高，28.01mmHg-35.76mmHg，平均32.11mmHg。
福州市植被生态环境遥感定量研究

以福州市为研究区域,以陆地资源卫星TM影像为主要遥感信息源,在GIS数据的支持下开展了植被生态环境的系列研究,通过对植被覆盖的科学预测,初步掌握了福州植被在未来50年变化趋势;根据这些研究结果,设计出了生态环境速查技术并对福州生态环境进行监测,评价获得了基于遥感信息的生态环境等级;随着研究的深入,又开展了直接反映生态环境状况的遥感本底值的研究,获得了福州生态环境遥感本底值,为实现业务化监测奠定了基础;最后根据遥感监测结果和GIS数据在人工智能和虚拟技术的支持下对典型区进行了3维虚拟表达,为智能化决策提供了借鉴。