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1.
胃癌术前介入治疗的临床和病理观察(附250例报告)   总被引:9,自引:0,他引:9  
研究和评估胃癌患者前介入治疗的疗效。方法;对250例胃癌患者术前进行了介入治疗,采用Seldinger法经一侧股动脉置管达部肿部位主要动脉,一次性注入化疗药物,5-Fu500mg/m^2,Epiadramycin 400mg/m^2,mmc15MG/M^2。在化疗后7-10天后行根治性切除术,介入组中随机选择82例并观察大体标本和癌肿组织病理学改变,对照组40例术前未进行化疗,直接手术切除,进行病  相似文献   

2.
饲料中的钙磷含量与河蟹生长的关系   总被引:1,自引:0,他引:1  
在水族箱中用体重29-33g的中华绒螯蟹蟹种对配合饲料中适宜的钙磷含量进行了研究。磷分设3个水平:1.2%,1.7%和2.2%;钙分设3个水平;1.5%,2.2%和2.9%。水体中钙含量为40.5mg/L,磷为0.04mg/L。试验全期27d,以蟹体生长、生长比率(SGR)、蛋白质效率(PER)和饲料系数(FCR)作为试验指标。结果表明,饲料中适宜的钙磷含量分别为2.9%和1.7%,钙磷比为1.7  相似文献   

3.
生长调节物质对丹参叶片脱分化及根芽分化的效应   总被引:11,自引:1,他引:11  
生长调节物质对丹参叶片脱分化及根芽分化效应的研究结果表明:(1)0.5~5.0mg/L2,4-D,0.1~0.5mg/LNAA0.5~1.5mg/LIBA或0.2~1.0mg/L4PU-30诱导叶片的脱分化率高达97%~1000%。(2)0.1~0.5mg/LNAA或0.5~2.0mg/IBA诱导芽化率为93%~100%,3种细胞分裂素中,4PU-30对叶片芽化最有效,6-BA和KT次之。(3)随  相似文献   

4.
锥花丝石竹快速繁殖参数的探讨   总被引:1,自引:0,他引:1  
文中探讨了两个锥花丝石竹品种组织培养快速繁殖过程中激素组成对繁殖倍数、有效苗指数、诱导生根苗指数、年产苗量和生根率的影响。结果表明:激素浓度为6BA0.2mg/L~0.5mg/L、IAA0.2mg/L~0.5mg/L的条件下,t值介于6~7之间,a/k值小于1,一个芽的年产苗量大约为1×104株~1×105株。这一繁殖倍数既可达到快繁的目的,又可保证苗的健壮度。锥花丝石竹的生根则以1/2MS加NAA0.5mg/L,IBA0.5mg/L最适宜,两个品种的生根率均可达98%。  相似文献   

5.
对绿色巴夫藻pavlavaviridis进行了生态条件试验,认为该藻能适应光强500-2500Lux;适温范围5-33℃,最适20-26℃;密度1.005-1.040g/cm3,最适1.005g/cm3;pH5-9都可以满足其正常生长,通过单因子和正交试验表明:培养液的较佳配方是在天然海水中加入(NH2)2CO-N20mg/dm3,KH2PO4-p1mg/dm3,FeSO4-Fe0.2mg/dm3,维生素B11mg/dm3和维生素B120.005mg/dm3。  相似文献   

6.
水镁石纤维是天然产出的、罕见的高镁实心纤维。其抗拉强度为95×9.81×10 ̄6Pa,弹性模量为1.5~2.0×9.8×10 ̄9pa,显微硬度为70~240,密度为2.44~2.48g/cm ̄3。电阻率为3×10 ̄5Ω.m~6.1×10 ̄7Ω.m,介电常数为4.7~7.2,磁化系数为11.5~15.5cm ̄3/g。耐热区间为450~480℃,导热系数为0.131w/m·k,热膨胀系数为5.7~8.8×10 ̄(-7)m/℃,热容为1.26I/g,热解焓为19.6KJ/mol。Ne=1.575~1.577,No=1.552~1.556,白度73.5%。本文还讨论了上述物理性质的各种变化、影响因素及其应用。  相似文献   

7.
拟除虫菊酯对昆虫 ATPase 的影响研究   总被引:3,自引:0,他引:3  
美洲大蠊中枢神经系统ATPase活力测定的最适反应条件是:对于Na+-K+-ATPase,蛋白质含量5~10μg,pH值7.0,反应温度30℃,反应时间15min.Km和Vmax分别为5.38×10-3mol/L和143.75nmol/min·mg-1.Ca2+-Mg2+-ATPase基本相同,只是pH值为7.4,Km和Vmax分别为2.64×10-4mol/L和46.28nmol/min·mg-1.初步研究了氯氰菊酯及氰戊菊酯的不同异构体对ATPase的影响,结果显示均对ATPase有不同程度的抑制,与生测结果不完全一致.  相似文献   

8.
低功率密度微波辐射对人细胞的非热效应   总被引:2,自引:0,他引:2  
采用频率为2450MHz,功率密度为3,5和7mW/cm^2的微波照射人精子1h,发现3mW/cm^2和7mW/cm^2的微波对人精子的活动度、存活率、畸形率和穿卵率没有任何影响,而5mW/cm^2的微波对从精子的活动度、存活率、畸形率及其穿卵率有显著的影响。实现表明,微波的非热效应不仅存在,且在5mW/cm^2附近有明显的功率密度窗效应。  相似文献   

9.
研究了转基因油菜R0、R1、R2代的Km抗性。试验结果表明:芥菜型油菜R0的1,5,6,7,8,10号无性系可抗Km50mg/L,其余的均抗Km35mg/L。R1种子在Km20mg/L的生根培养基上进行生根抗性试验,生根与不生根的比例经适合性检验(x2检验)有10个无性系符合孟德尔单基因分离的遗传规律,只有两个无性系不符合这一规律,出现了较高的抗性苗比例(34:2;40:6)。R2代共做了7个单株的种子抗性试验,其中6个单株的种子出现3:1的分离比,一个单株没有发生分离,种子全部可抗Km。  相似文献   

10.
正交设计法在白三叶组织培养中的应用   总被引:17,自引:0,他引:17  
以白三叶的叶片为外植体,采用正交设计法,对愈伤组织生长和细胞悬浮培养的培养基进行了优化筛选。实验结果表明,白三叶叶片愈伤组织生长的最佳培养基配方为MB+0.5mg/L 2,4-D+0.2mg/L NAA+1mg/L BA+2mg/L甘氨酸+100mg/L肌醇+3%蔗糖+0.7%琼脂;细胞悬浮培养的最佳培养基的配方为MB+4mg/L 2,4-D+0.2mg/L NAA+0.5mg/L BA+2mg/  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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