共尾性

The cofinality of a set of ordinals or any other well ordered set is the cofinality of the order type of that set.

序数或任何其他良序集合的集合的共尾性是这个集合的序类型的共尾性。

So the cofinality operation is

所以共尾性运算是

All superclasses of closed unbounded classes are stationary and stationary classes are unbounded, but there are stationary classes which are not closed and there are stationary classes which have no closed unbounded subclass ( such as the class of all limit ordinals with countable cofinality ).

所有闭合无界类的超类是固定的并且固定类是无界的，但是有着不闭合的固定类并且有着没有闭合无界子类的固定类(比如带有可数共尾性的所有极限序数的类)。

For example, the cofinality of ω is ω, because the sequence ω·''m''( where ''m'' ranges over the natural numbers ) tends to ω; but, more generally, any countable limit ordinal has cofinality ω.

例如，ω的共尾性是ω，因为序列ω·''m''(这里的''m''取值于自然数之上)趋向于ω；但是，更加一般的说，任何可数极限序数都有共尾性ω。

The cofinality of any ordinal ''α'' is a regular ordinal, i.e. the cofinality of the cofinality of ''α'' is the same as the cofinality of ''α''.

任何序数''α''的共尾性是正规序数，就是说''α''的共尾性的共尾性同于''α''的共尾性。

Notice that a number of authors define confinality or use it only for limit ordinals.

注意很多作者只对极限序数定义或使用共尾性。

There were 36 males and 40 females,with the average age of 47.7 years.36 patients presented with sciatica and perineal numbness,11 patients had painless mass and the other 20 were identified due to other causes.Among 67 benign neurogenic tumors,54 were originated from S1-S3 nerves,3 from S4-S5 nerves and 11 from the presacral space without caudal involvement.Giant cell tumor was found in 60 patients,which included 24 males and 36 females,with an average age of 32 years.Upper sacrum（S1-S2） was involved firstly.There were 56 patients（average,37.7 years） diagnosed as other primary benign bone tumors,which included 24 cases of teratomas,epidermoid cyst or dermoid cyst.Other malignant tumors,including chondrosarcoma （17）,Ewing′s sarcoma/PNET（14）,multiple myeloma（12）,lymphoma（6） and osteosarcoma（6） were found in 64 patients.

其中脊索瘤95例，男62例，女33例，平均年龄55.7岁，骶尾区疼痛是主要症状（82例），半数以上患者伴有坐骨神经痛，肿瘤多先累及低位骶骨（S3~S5）；神经源性肿瘤76例，男36例，女40例，平均年龄47.7岁，神经纤维瘤43例，神经鞘瘤24例，恶性神经鞘瘤9例，主诉多为坐骨神经痛、会阴部麻木（36例）和无痛性包块（11例），20例患者为查体或其他原因检查时发现，67例骶骨良性神经源性肿瘤起源于S3以上神经者54例，起源于S3以下神经者3例，发生于骶前未累及骶管者10例；骨巨细胞瘤60例，男24例，女36例，平均年龄32岁，腰骶尾部不适（37例）、坐骨神经痛（21例）是主要的临床表现，肿瘤多先累及上位骶骨（S1~S2）；骶骨其他原发良性肿瘤及瘤样病变56例，包括畸胎瘤、皮样囊肿、表皮样囊肿共24例；其他原发恶性肿瘤64例，包括软骨肉瘤17例，尤文肉瘤14例，多发性骨髓瘤12例，成骨肉瘤6例等。

On the 10th ,20th ,30th,40th and 50th day, cut the tail of each mouse to make blood smears, stained the smears by Wrights method, and counted the erythrocyte containing HowellJolly bodies, or containing basophilic stipplings, or showing polychromatophilia, or showing hypochromic.

昆明种成年雄性小鼠15只，随机分成两组，实验组10只饮用2g/L硝酸铅溶液(1251mgPb2+/L)染毒，共50d。每10d切尾涂片一次，分别镜检计数含HowellJolly小体RBC，嗜碱性点彩RBC，嗜多色性RBC及低色素性RBC的出现率。

Nov. mainly inhabits those channels such as mahuang channel、gari channel、bori channel、heping channel and dengchi channel. So it belongs to the distribution area extremely narrow type. From May to October 2005 and May to August 2006, 671 specimens collected were used for studies on the reproductive strategies such as reproduction time, spawning type, the ratio and the fecundity, and gonad development and characters of early life history. The main results are as follows: 1.Every year speaking of spawning season the male"s is earlier than female"s slightly.

Nov。仅分布于宝兴河支流东河盐井以上河段，主要分布在蚂蝗沟、嘎日沟、波日沟、和平水域及邓池沟，属于分布区极其狭窄的种类。2005年5月—10月和2006年5月—8月共采集671尾标本，运用常规生物学指标的测定分析法和性腺的组织切片法，以及对成熟亲鱼人工授精获得的胚胎在立体显微镜下活体观察，研究其繁殖期、产卵类型、性比和繁殖力等繁殖策略及性腺发育和早期发育。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。