主要原因

The reason for primary amenorrhea is very complicated. One of the main causes is chromosome anomalies.

原发性闭经是一种原因复杂的疾病，染色体异常则是发病的主要原因。

The difference in anaerobe distribution and granule size between the two kinds of sludges resulted in smaller sorption capacity of sludge from EGSB reactor, which made the difference in resistance to PCP.

两种颗粒污泥微生物组成的差异和粒径大小的不同是导致EGSB反应器颗粒污泥对PCP的吸附量小于UASB反应器颗粒污泥的主要原因，而这是两种厌氧颗粒污泥对PCP毒性耐受能力不同的原因之一。

It has been one of the… if not the principle reasons behind the worldwide rise in anti-Americanism since 2001

如果说自2001年开始的反美运动的主要原因不是伊拉克战争，它至少也是其中之一的原因。

Terms to know: Habeas Corpus Emancipation Emancipation Proclamation Fort Sumter Confederacy Union Thirteenth Amendment Ironclad ships Harper's Ferry Secession Trent Affair Conscription Uncle Tom's Cabin Battles to know: Gettysburg Shiloh Bull Run Antietam Vicksburg Chancellorsville Concepts to know Resources of Union start of war Resources of he Confederates start of war Anaconda Plan Concept of "Total War" Causes of the War Acts of protest before and during the war Lincoln's main reason for war How war affected the economy of the Confederacy How war affected the economy of the Union Other: Andersonville Fort Pillow Appomattox Court House Gettysburg Address Battlefield Medicine

条款知道：人身保护令解放解放宣言桑特堡邦联联盟第十三条修正案铁船哈珀的渡轮分裂国家特伦特事件征兵汤姆叔叔的小屋战斗知道：葛底斯堡希洛牛市安蒂特姆维克斯堡钱概念知道资源的联盟开始的战争资源Confederates开始他的战争蟒蛇计划观念的"总体战"原因战争抗议行动之前和战争期间林肯的主要原因战争如何受战争影响的经济邦联如何受战争影响的经济联盟其他：安德森维尔堡枕头阿波马托克斯法院大楼葛底斯堡演说战地医学

Analyses of the water quality variation show that aquiculture is a main source of organic pollution, and the growth of the urban population is the main reason for nutrient pollution.

分析总结了水质污染变化原因，指出衡阳市养殖业的发展成为衡阳段有机污染的重要来源之一，城镇人口增加是营养型污染增加的主要原因。

Generally,the cause that deaf children cannot speak correctly and articulately is that they are not good at breath-control while speaking.

聋儿说不好话的原因，其共性和主要原因是发音说话不会控制气息所致。

Objective:to investigate the cesarean section of the reasons for the bleeding, and lower the rate of obstetric hysterectomy possibility.methods: 30 cases in our hospital cesarean section in the clinical data of patients with hemorrhage were retrospectively analyzed.results: in 30 cases of bleeding, placental factors accounted for 53.33%, 36.67% of the uterine atony, uterine incision bleeding laceration of 6.67%, 3.33% of the amniotic fluid embolism, hysterectomy three cases.conclusion:placenta, uterine atony cesarean section is the main reason for the bleeding.

目的：探讨剖宫产术中大出血的原因及降低产科子宫切除率的可能性。方法：对我院30例剖宫产术中大出血患者的临床资料进行回顾性分析。结果：30例大出血中，胎盘因素占53.33%，宫缩乏力占36.67%，子宫切口裂伤出血占6.67%，羊水栓塞占3.33%。治疗结果中，子宫切除3例，占剖宫产术的0.076%（3/3 935）。结论：胎盘因素、宫缩乏力是剖宫产术中大出血的主要原因。

The common reason for prospective memory failure reported in the question-naire was that background task was allocated overwhelming attention.

被试自陈的预期记忆失败原因是背景任务占用了他们的注意资源；老年被试的注意资源减少是其预期记忆衰退的主要原因。

However, with the rapid development of the small town, some problems and contradictions about the small town planning and construction in the Midwest Lack-developed Areas emerge by and by: lots of small towns have not transparent tactic steering and scientific economic management mechanism and pattern, leading to construction confusion, ground use squandering, environment pollution, industrial structure reasonable, infrastructure layout disharmonize; without supervise law and rule in the small town construction, leading to the small town being be out of harmony with the area, the function of small in the area is restricted; the small town resource being used freely, and the administration coming to chaos, leading to repetition construction, resource waste, and so on.

论文以"三农"问题为切入点，紧紧围绕中西部欠发达地区小城镇规划与建设所面临的关系小城镇未来发展的三个关键问题：土地利用、生态环境和基础设施建设等进行深入剖析，分析问题产生的原因：城乡二元结构是导致小城镇建设问题的主要原因；观念保守，体制不健全；财政财力不足，基础设施资金投入比例低；规划落后于建设，规划中存在非科学因素；缺乏区域设施共建共享的有效机制。在此基础上提出解决问题的对策。

The welding juncture of the axis head and the surrounded plate in the holding circle of bessemer converter crack severely .By means of analysis to the material,the structure and the process,we find out that one of the main reason of crack is the thickness of welding plates vary a lot, the other is that it isn't penetrable for welding.

转炉用托圈的轴头与围板焊接处严重开裂，通过对其材质、结构、工艺进行分析，找出接头断裂的主要原因，一方面是由于焊缝连接件厚度相差悬殊，另一方面是由于焊缝未焊透，这两方面原因造成应力集中。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。