平均差

The soil and water loss which corrades easily becomes faster because of high air temperature, precipitation rain fall, violet red and brick red sandstone, undeveloped formation structure, bad fertility and little vegetation, and frequent and irrational human activity, etc.

原因是研究区月平均气温高，雨量充沛，岩石岩性以紫红、砖红色砂砾岩为主，地层构造不发育，土壤肥力差，植被生长困难，再加上人类活动频繁，以及不合理利用土地资源，使本来就易受侵性的土壤流失更迅速。

Statistical multiple according to the Duncan's SSR, cross-pollinated fruits showed significant difference in average fruit mass, transverse diameter, longitudinal diameter, fruit shape index and flesh firmness.

通过果实平均单果质量、横径、纵径、果形指数、可溶性固形物含量、硬度等内外观性状的新复极差多重比较分析，得出不同花粉对猕猴桃果实影响差异较大。

Lastly, the paper presents the fractional differenced noise model and the autoregressive fractional integrated moving average model.

接着给出能描述长记忆性的分数差分噪声模型和分整自回归移动平均模型。

Then the paper presents the fractional differenced noise model and the autoregressive fractional integrated moving average model. It compared traditional time series models with ARFIMA model.

接着介绍了能描述长记忆性的分数差分噪声模型和分整自回归移动平均模型，并将传统时间序列模型和ARFIMA模型进行比较。

Results Mean tumor enhancement were 48±8 HUand 72±6 HU, normal pancreas enhancement were 125±18 HU、98±11 HU, mean tumor-pancreas contrast was significantly differenced on arterial phase （73±21 HU）and portal venous phase （25±12 HU）.

结果 肿瘤的平均CT值在动脉期和门脉期分别是48±8 HU、72±6 HU，正常胰腺组织的CT值是125±18 HU、98±11 HU，肿瘤-胰腺密度差为73±21 HU、25±12 HU，二者之间有显著差别。

Total laminectomy or half laminectomy would be selected or the nerve root canal was decompressed and hypertrophied ligmentum flavum was removed along with the herriated disc was extirpated if necessary.results all cases were followed from 5 months to 77 months,with an average of 32 months.according to the nakai scale,the results were excellent in 254 cases,good in 41,fair in 5 and poor in none.including 3 cases who had been operated by microendoscopic tubular retractor,and another one had a history of chemonucleolysis.conclusion radiography is very important for suitable selection of surgical indication as well as the operation treatmeat of lumbar disc herniation and lumbar canal stenosis.

结果 术后随访5～77个月，平均32个月，按nakai标准评定疗效：优254例，良41例，可5例（其中在外地做过椎间盘镜术3例，木瓜酶溶核术后1例，而后到本院行此手术），差0例。结论影像学检查为腰椎管狭窄症，黄韧带肥厚的患者，体征与狭窄的定位，在腰椎间盘突出症和腰椎管狭窄症手术方式和适应证的选择上起重要作用。

ABSTRACT It is because that the excellent acceptors for maize transgenic engineering are insufficient in our country, especially in the southwest mountain areas of china and hereditary variation regularity for the two characters such as efficiency of embryonic callus induction and number of regenerating plant (these two characters were abbreviated to the nduction efficiency and number of regenerating in the following of the paper, respectively), which hint the maize culturing capacity, is not very clear. Therefore, aiming at picking out superior acceptors, we had made systematic researches on the two characters with combing traditional quantitative-character genetic analyzing methods such as single-factor genetic mating design, diallel crossing genetic design, genetic effect analyzing method and the modern molecular locating method such as QTLs'. The main results are followed.(1) 50 superior inbred lines and about 30 crosses in our country, especially in the southwest of China were used for identifying and selecting the superior genotypes in the above two investigated characters under the same culturing condition in 2000 and 2001. There was very significant difference among the genotypes in the both characters. But the two characters were not certainly related. Some genotypes such as 18-599 and 18-599 were very good in them. For some ones such as zong 31, induction was higher than 18-599 and 18-599 in the efficiency, but it was only 1/3 to the later in regenerating number. In some genotypes such as S37, R08, R15, P138, A318, induction efficiency was just about 3% and scarcely any regenerating plants were got. On the whole, hybrids acted better than inbreeds in the both characters.(2) Two kind of inbreeds were selected as parents of the Griffing's method 1. 18-599 and 18-599 and the inbred line zong 31 are one kind because they are not only superior in the characters of maize cross breeding, such as CA, resistance to disease and the important agricultural characters, but also excellent in transformation characters as the induction and regeneration.

针对我国、特别是西南山地所需玉米转基因工程育种优良受体极为匮乏和反应玉米幼胚培养能力的2个主要性状，即玉米幼胚胚性愈伤组织诱导率和胚性愈伤组织绿苗发生数的遗传变异规律十分不清楚的实际情况，本研究从筛选玉米转基因工程所需要的优良受体入手，采用单因素遗传交配设计、双列杂交遗传交配设计、世代基因效应等传统数量性状分析方法，以及现代分子标记定位主效QTL分析方法，对玉米幼胚胚性愈伤组织诱导率和胚性愈伤组织绿苗发生数等2个性状进行了较为系统的分析研究，取得以下主要研究结果：(1)于2000年和2001年通过对我国、特别是西南地区近50份优良自交系和近30个杂交组合，在相同培养条件下，对幼胚培养胚性愈伤组织诱导率和胚性愈伤组织绿苗发生数等2个幼胚培养能力性状进行了筛选与鉴定，发现玉米不同基因型具有完全不同的幼胚培养胚性愈伤组织诱导率和胚性愈伤组织绿苗发生数，但幼胚培养胚性愈伤组织诱导率与胚性愈伤组织绿苗发生数并不具有必然的相关关系，有的基因型，如自交系18-599和18-599在胚性愈伤组织诱导率和愈伤组织绿苗发生数等2个性状都表现相当优异；有的基因型，如自交系综31，仅幼胚培养胚性愈伤组织诱导率性状表现高于19-599和18-599，但在胚性愈伤组织绿苗发生数这一性状则与它们有相当大的差距，仅为19-599和18-599的1/3左右；有的基因型，如S37、R08、R15、P138、A318等玉米自交系不仅幼胚培养胚性愈伤组织诱导率很低，平均仅在3％左右，而且胚性愈伤组织绿苗发生数表现也很差，基本上没有分化成苗。

The prognoses of these patients are extremely poor with a mean survival time of only 7.6 weeks.

这些病人的预后很差，平均存活时间只有7.6周。

After analyzing the impacting factors of natural vulnerability along the Pearl River mouth, the paper divides the coastline of approximately 412km into 25 15-minute gird cells. For assessment purposes, the six variables including geography, relative sea-level change, average tide range, regional slope, shoreline erosion or accretion rates and tropic cyclone impacting frequency are selected as assessed variables. Once each section of coastline is assigned a risk value for each specific data variable, the costal vulnerability index can be useto calculate the natural vulnerability of the areas along the Pearl River mouth. After that, the paper develops a database for assessment of coastal vulnerability to sea-level rises and protracts a 1:2,000,000 vectors CVI map of the coastlines along the Pearl River mouth.

为了探讨不同海岸带对未来海平面上升的自然脆弱性，本文以珠江口沿岸作为研究个案，在分析珠江口沿岸自然脆弱性的影响因子的基础上，把珠江口沿岸412km岸线划分为25个15′×15′的网格单元，选取了地质、海平面上升率、平均潮差、区域海岸坡度、海岸侵蚀/堆积率、热带气旋影响频率6个评价指标，应用CVI指数评价公式对珠江口地区进行海岸脆弱性评价，并建立海岸脆弱性评价数据库，绘制了珠江口沿岸1：2，000，000的数字化CVI图。

Reasonably well compared with those in other countries, average standards are not improving despite billions in extra spending, and a stubbornly long tail of underachievers straggles behind.

虽然说与其他国家相比，英国学生表现的略好一些，但数十亿额外开支并没有将学生的平均水平带动上去，并且还有一大群差等生在后面拖后腿。

I'm gonna go pack my regular, long bathing suit.

我要去打包我那不起眼的超长泳裤

Random number generators are used in many areas, with the improvement of the computational ability of the computer.

随着计算机计算能力的不断提高，随机数发生器在许多领域有了更加广泛的应用。