双丝

To investigate whether the expression of cdc2 and cyclin B1 in spermatogenic cells during spermatogenesis is actually a temperature dependent event, in situ hybridization, Western blotting and immunohistochemistry analysis were used to study the expression of cdc2 and cyclin B1 in normal and cryptorchid testis. Results showed that heat would differentially hurt male germ cells in different developmental stages during spermatogenesis, especially the pachytene primary spermatocytes. Most of spermatogonia in contralateral cryptorchid testis were not harmed fatally by heat as yet, indicating that spermatogonia could resist to beat to a certain extent. In this case spermatogonia could develop to pachytene/diplotene primary spermatocytes, but they could not acquire the ability to complete the transition from mitosis to meiosis, and then appeared to go through apoptosis. Therefore, we could not find the descendants of meiosis: secondary spermatocytes and round spermatids, elongated spermatids and spermatozoon. The abdominal temperature had no significant influence on the transcription of cdc2 and cyclin B1 in the spermatogonia and pachytene/diplotene primary spermatocytes. In normal rabbit testis, cyclin B1 increased in the pachytene/diplotene primary spermatocytes before meiosis and reached its peak in the spermatids.

为了解精子正常发生过程中cdc2和cyclin B1表达的低温依赖性，我们利用原位杂交和免疫组化等方法，研究了正常和隐睾精子发生过程中cdc2和cyclin B1的转录和翻译调控活动，结果表明：（1）热对各阶段的雄性生殖细胞都有损害，粗线期的初级精母细胞尤为敏感，实验性隐睾内的精原细胞尚未完全受到"致命"影响，说明精原细胞对热有一定的耐受性，但即使成为粗线期／双线期初级精母细胞，却未能获得由有丝分裂过渡到减数分裂的能力，呈现不同程度的凋亡，所以在整个切片中找不到源自减数分裂的产物----次级精母细胞、圆形精子细胞，更谈不上长形精子细胞和精子的形成；（2）腹腔高温未明显地影响隐睾精原细胞和粗线期/双线期初级精母细胞中cyclinB1和cdc2的转录，说明高温并不是通过影响cyclin B1和cdc2的转录活动而导致生精过程阻断的；（3）正常兔睾丸组织中，〓在精原细胞和粗线期／双线期精母细胞中均有表达：cyclin B1蛋白在减数分裂前期的粗线期／双线期初级精母细胞中的表达量增加，于变态末期的精子细胞中达高峰。

The tore equipment of Two-For-one Twisterfor Filament,which can wind different forms semifinished yarn into double- cone bobbin yarn.

本机用于将原不同形状丝还络成具有一定规格的双锥型筒丝，供各种国产及进口倍捻机丝用，本机是倍捻机及捻线机必备的前道配套设备。

The main work is as followings: First, we use KE SI DA microscope for observing the appearance and configuration of bicomponent fiber. It was found in the bicomponent fiber it is a bilateral array for the PET and PTT. The cross section is anisomerous with PTT and PET side by side. After heat treating the shape of single filament becomes three dimensional curly and the number of crimp is biggest in the condition of relaxation. In the range of some tention, the bulkiness and crimpness fall obviously after the bicomponent fiber is treated with heat.

首先利用科视达观察了PTT/PET双组分复合纤维的外观形态，发现PTT/PET双组分复合纤维中PTT、PET两种组分呈双边分布，横截面呈不对称的哑铃状，PTT和PET两组分分居在横截面两侧，单丝经热处理呈现出三维立体卷曲，在无张力条件下卷曲数最多，在一定的张力范围内，随着所加负荷的增加，PTT/PET双组分复合纤维热处理后的蓬松性及卷曲性均下降显著。

Upon binding ATP or a nonhydrolyzable analog such as AMPPNP, RecA undergoes an allosteric transition into a high-affinity DNA-binding form. When RecA combines with dsDNA to form RecA-dsDNA nucleofiliment, it can unwind dsDNA and change the dsDNA structure.

在ATP或其类似物的辅助下，RecA可以直接与双股DNA结合而形成核丝，并将双股DNA加以解螺旋，并改变双股DNA的结构。

In this study, genetic analyses were conducted to determine the genetic basis in an elite resistant inbred line Siyi with complete resistance to maize dwarf mosaic. A new genetic model, two dominant complementary genes conditioning the resistance, were found by Mendelian genetic analysis based on parents, F1, F2 and backcrosses in three successive years' field trails. The two genes were further mapped near the centromere of chromosome 3 and 6, respectively by tightly linked microsatellite markers using 242 plants from F2 generation. The resistance gene on chromosome 3 is 1.0 cM apart from the flanking markers phi053 and umc1527, respectively. Whereas the linkage distance between two flanking markers bnlg1600 and phi075 and resistance gene on chromosome 6 was 1.0 and 4.0 cM, respectively. Genotypic analysis of the plants from testcross and F3 populations supported the new genetic manners.

课题组通过连续三年的抗病鉴定，在国内种质资源中筛选出一份综合农艺性状优良、配合力较高的自交系四一，三年的表型遗传研究和两年的分子标记工作，发现四一中的玉米矮花叶病抗性是由两对显性互补基因控制的，进而利用F2作图群体，把发现的两个基因定位在第三和第六染色体的着丝点附近，并获得了双侧紧密连锁的分子标记连锁图谱，其中第三染色体上的分子标记UMC1527和phi053从抗病基因双侧逼近1 cM，而第六染色体上的分子标记phi075、bnlg1600从抗病基因双侧分别逼近4 cM和1 cM；利用B2群体、F2：3家系、BC3F1群体和带有第三、第六染色体抗病基因以及两个抗病基因的近等基因系，进一步证实了四一中成株期抗性是由两个显性互补基因控制的。

GB screw, self-produced self-Pin (4-56) high-strength screw, lead screw 12-48 ladder deduction is deducted,·, joint mother, Cone's mother, tubes, implosion, custom-made single-head, double-headed, anchor bolts and all kinds of special pieces, quality reliable, delivery timely, available year-round spot.

国标丝杠、自产自销(4-56)高强度丝杠、梯型扣丝杠12-48、正扣、反扣、接头母、锥型母、管、内爆、订做单头、双头、地脚螺栓及各种异型件，质量可靠，供货及时，常年备有现货。

Longfeng car foot pad is a professional firm to produce automobile foot factory, although the establishment of only a few years time, but varied Products include nylon fabric, the United Statesáfabric, polypropylene fabric twine, monofilament polypropylene fabric, silk-e-day fabric, jacquard fabric stock, high-cut fabric at the end of lap, two-color jacquard fabric with multi-color jacquard fabric.

隆丰汽车脚垫商行是专业以生产汽车脚垫的工厂，虽然成立只有短短几年时间，但产品多样包括有尼龙面料、美尼丝面料、丙纶合股面料、丙纶单丝面料、天娥丝面料、合股提花面料、高割底圈面料、双色提花面料与多色提花面料。

The use of a large number of wires in annular Z-pinch implosions has enabled the generation of strong X rays,which is significantly affected by the structure of the wire-array and the assembly precision of the wires.

在利用金属丝阵Z箍缩产生强X射线辐射的方法中，为获得超强X射线，一般采用直径几μm的钨丝构成单、双或多层圆柱面状丝阵负载，其中丝阵负载的结构和装配精度是关键因素。

In this paper, the structure and its morphology of the as-spun isotactic polypro- pylene monofilaments has been investigated by using cross polarized microscope, SALS, SEM, WAXD, density, birefringence and Hardy's thin cross-section device.

本文采用正交偏振光、小角激光散射、扫描电子显微镜，广角X光衍射、密度、双折射和切片技术，对工业用丝——IPP单丝的未拉伸丝的结构及其形态进行了广泛的研究。

Double Circle Fence, also known as double-lap Fence, which uses 2.5mm cold-welded together, after drawing, each hizontal wire mesh has a curved arc to increase the strength.

双圈护栏网又称为双圈隔离栅，它采用2.5mm 冷拉丝后焊接而成，每个网孔的横丝有一个弯弧，以增加强度。

I am accused of being overreligious," she said in her quiet, frank manner,"but that does not prevent me thinking the children very cruel who obstinately commit such suicide.""

客人们在卡罗利娜·埃凯家里，举止就文雅一些，因为卡罗利娜的母亲治家很严厉。

Designed by French fashion house Herm è s, this elegant uniform was manufactured in our home, Hong Kong, and was the first without a hat.

由著名品牌 Herm è s 设计，这件高贵的制服是香港本土制造，是我们第一套不配帽子的制服。