usually occur

However, malignancies usually occur when fragments of these tumors are transplanted in other rats.

但如把此肿瘤的组织块移植于其他大鼠则经常表现出恶性.

Ingrown toenails usually occur in the big toe.

指甲内嵌通常发生在大拇指上.

Its clinical symptoms are recurrent episodes of wheezing, expiratory dyspnea, chest tightness and cough, which usually occur at night and or in the morning, and could be released spontaneously or with appropriate treatment.

临床上表现为反复发作性的喘息、呼气性呼吸困难、胸闷、咳嗽，常在夜间和或清晨发作，症状可自发缓解或经治疗后缓解。

They usually occur along the boundaries of the thin plates that cover the Earth like an egg shell.

地震一般都在较薄的板块边缘沿线发生，而较薄的板块对地球而言就像鸡蛋壳一样。

Small precursory events usually occur before strong instability involving the intersecting faults.

涉及交叉断层的较大失稳事件发生前常出现前兆性小事件。

The respiratory behaviors usually occur when they are in the middle of water.

母仔豚呼吸行为多发生在夹江中心水域。

Faulf of electric equipments usually occur in their use.

电气设备使用中经常会出现故障。

II. Inevitable abortion is a threatened abortion with a dilated cervical os. Menstrual-like cramps usually occur.

难免流产是指先兆流产时宫颈口扩大, 腹痛类似于经期腹痛.

The mutations usually occur in mucous malignant cancer and the mutation rate is increased significantly.

polβ基因突变多发生在粘膜性恶性肿瘤，并且突变发生频率也相对较高。

Merge and acquisition usually occur in capital intensive industries.

并购活动通常发生在资本密集型行业。

Tunnel projects usually occur in city where high-rise building and elevated bridge etc have badly concentrated.

地铁工程建设多滞后修建于高层建筑、高架桥梁等已高度密集的城市环境中。

Elastic fibers usually occur as individual , refractile, branching, and anastomosing fibers.

弹性纤维通常是单独的, 折光的, 分枝的及吻合的纤维.

The breakthrough of gas usually occur during low permeability reservoir development, that lead to recovery efficiency fall.

低渗透油藏注气开发极容易发生气窜，导致采收率降低。

This class of problems usually occur in many scientific and engineering fields.

此类问题时常出现在许多科学与工程的研究领域内。

The valve regurgitate flow usually occur in multiple mainveins in DDVI, and in femoral veins in DVI.

DDVI组发生返流瓣膜组合是以多条大静脉同时出现为主,而DVI组则以单根为主.

BACKGROUND: Vascular complications usually occur in diseases related to obesity such as primary hypertension or diabetes.

背景：原发性高血压、糖尿病等肥胖相关性疾病往往出现血管并发症，活血化瘀法治疗肥胖症有一定疗效，据此推测肥胖与血瘀证可能相关。

In blasting engineering work, the influence of complicated geological conditions whiCh usually occur on blasting effect comes in many ways.

定向爆破工程中，爆区地质条件往往很复杂，因此对爆破效应的影响也是多方面的。

Goods normally leave the factory on time. Any delays usually occur in the course of delivery.

工厂平常都会准时出货, 延误往往发生在送货中.

Hepatitis B, C and D usually occur as a result of parenteral contact with infected body fluids.

发生乙型、丙型和丁型肝炎通常是由于通过非肠道途径接触了受感染的体液。

Tropical cyclones in the Bay of Bengal region usually occur in the non-monsoon months.

该研究指出，在有记录的历史中，印度洋北部首次在2007年6月形成了一场5级热带飓风以及两个更猛烈的热带风暴。孟加拉湾地区的热带气旋通常发生在非季风时期。

Reunions usually occur every five years , beginning five years after graduation.

聚会常常是五周年一次,从毕业离校的五年后开始.

These two kinds of lesions usually occur within 3 months after birth.

婴儿湿疹和婴儿脂溢性皮炎好发于出生后3个月以内的婴儿，后者可能是由于母体雄性激素的影响。

They usually occur during stressful moments, such as when a person is in danger.

它们通常出现在压力大的时候，比如说当人处于危险中。

Osteoporosis is usually occur concomitantly with arterial calcification in elderly.

众所周知老年患者发生骨质疏松的同时常常伴发血管钙化。

They usually occur in high stakes situations, where people have something to lose or gain.

微表情通常会在人们经历得失、情势危急的时候出现。

Elastic fibers usually occur as individual, refractile, branching, and anastomosing fibers.

弹性纤维通常是单独的，折光的，分枝的及吻合的纤维。

Terrible things usually occur at midnight.

可怕的事情通常在午夜发生。

In many plants, including most tree crops, nitrate nitrogen does not usually occur in the leaves.

在一些植物中, 包括绝大多数的木本作物, 硝态氮并非经常存在于叶片中.

The events callbacks usually occur at the time of parsing.

事件回调通常在进行解析时发生。