细胞发生

The ultrastructural changes during the development of sieve element companion cell complex (SE/CC complex) in Populus deltoides were investigated using electronic microscopy. The result showed that SE and CC tome from the same secondary phloem mother cell. The development of sieve element went through three stages, i. e. immature, mature, and degenerate stage. In immature stages the sieve element presented radial expansion, cell wall thickening, and production of sieve plastid and P-protein. The cytoplasma selectivly autolysed in mature stage. At the same time, karyoplasm was dispersed, and nuclear envelope was not clear, or karyoplasm was disorgnized, and nuclear envelope was clear. The karyopalsm finally turned into P-protein. In degenerate stage, the cytoplasm completely disappeared, and the function was lost.

利用电镜技术研究美洲黑杨次生韧皮部筛管和伴胞发育过程中细胞超微结构的动态变化，观察到筛管和伴胞由同一个次生韧皮部衍生细胞分裂分化形成筛管约发育历经未成熟期、成熟期和衰退期的变化未成熟期筛管分子表现为细胞的径向扩展、壁的增厚、筛管质体和P-蛋白质的产生；成熟期筛管分子细胞组分发生选择性自溶，细胞核核质弥散状，核膜不清晰，或核膜清晰而核物质降解，最后细胞核完全解体转化为P-蛋白质类的物质；衰退期筛管分子细胞质完全解体消失，失去功能。

Numbers of secretory granules, oplasmic reticulums, mitochondrias in ACTH cells all changed distinctly. GTH cytoplast were full of big and small, high density electron secretory granules.STH cells were in activity synthesis and secretion, secretory granules were from fusion to release. TSH cells cytoplast evacuated secretory granules, electron density decreased and vacuofes appeared.

ACTH细胞分泌物颗粒数量、内质网及线粒体均发生明显变化；GTH细胞胞质中充满电子密度较高的大、小两种分泌颗粒；STH细胞处于活跃的合成和分泌状态，分泌颗粒呈现出由融合到释放的状态；TSH细胞胞质中分泌颗粒排空，且电子密度降低，出现大空泡。

Necrosis and apoptosis that gradually increase and eventually result in enervation and death of chicken with selenium-penia. The effect of selenium on the lipid peroxidation of the cellular membrane system of tissues is the main mechanism that selenium induces apoptosis of tissues.

雏鸡硒缺乏时，甲状腺、肝脏、胸部肌肉、胰腺、胸腺等组织细胞凋亡增加，证明硒缺乏雏鸡体内发生两种细胞死亡，即坏死和细胞凋亡，由于细胞坏死和凋亡的加重与增多，致使硒缺乏雏鸡走向衰竭，最后死亡。

CD44 is a single strand glucoprotein family encoded by single gene on the memebrane surface with high heterology,which can mediate adhesion between cell and cell as well as cell and extracellular matrix.Its different splicing variants will result in the variety of its gene products.Especially,its splicing varant V6 (CD44v6) is condided to have oncogenicity.CD44v6 takes part in the genesis and development of tumor at some certain and is one of prognostic factors.So it will be the marker indicating tumor development.

CD44是由单一基因所编码的具有高度异质性的单链膜表面糖蛋白家族，介导细胞与细胞、细胞与细胞外基质之间的黏附作用，其拼接变异体的不同构成了其基因产物的多样性；尤其拼接变异体V6(CD44v6)被认为具有致瘤性；CD44v6在一定程度上参与了肿瘤的发生发展，是预后因子之一，并且可能作为肿瘤进展的标志物。

Other reported cases in the prostate include a clear cell carcinoma of the prostatic utricle in a 16 year old boy reported from Uruguay and a renal cell type of prostatic carcinoma which lacked hobnail cells and had staining patterns similar to renal cell carcinoma.

其他有关前列腺透明细胞癌的报道有两例，一例发生在乌拉圭的一个16岁男孩的前列腺囊，另一例报道为前列腺癌的肾细胞型，此类型没有靴钉样细胞，而是与肾细胞癌相似的染色形式。

The difference of survivin expression intensity was statistically significant (P.05). Conclusion: A suitable-expression of survivin in normal early gestation villi may be crucial for embryo karyokinesis and cell proliferation. An over-expression of survivin in GTDs may be an important role in their oncogenesis.

适度survivin是正确完成胚胎细胞有丝分裂和细胞增殖的必要条件，因survivin的过表达引起的细胞凋亡阻滞在妊娠滋养细胞疾病的发生发展过程中可能起重要作用。

The protoxylem vessels initiated lignification in the early stage of vascular bundle differentiation, whereas metaxylem vessels and fiber walls started lignification from the middle lamella and cell comers after completion of vascular bundle differentiation. The walls of most parenchyma cells lignified after the stem reached its full height, while a few parenchyma cells remained non-lignified even the culm is 7 years old.

研究结果表明：毛竹茎的原生木质部导管在维管束发育早期就已木质化；后生木质部导管和纤维细胞在维管束分化完成后，自胞间层和细胞角隅处开始木质化；基本薄壁组织细胞木质化的发生较晚，通常在茎的节间完成伸长生长后才开始，但也有少数薄壁组织细胞始终保持非木质化的薄壁状态。

However, it remains to be determined if virion attachment to target cells is sufficient to induce cell death, or if apoptosis is triggered directly or indirectly by one or more virion-associated proteins.

但是，是毒吸附细胞表面诱导凋亡的发生还是病毒的一个或多个结构蛋白诱导细胞凋亡的发生还有进一步的研究。

At 24 h, Ang1 was expressed mainly in the lens, optic cup, mesencephalon, ventral part of hindbrain, and myotomes in the somites, while zfTie2 was mainly expressed in intersomitic vessels including dorsal aorta and axial veins, and sprouting vessels from the dorsal aorta in the trunk. VEGF was expressed mainly in the lens, optic cup, mesencephalon and myotomes in the somites, while zfFlk1 was mainly expressed in intersomitic vessels including dorsal aorta and axial veins, and sprouting vessels from the dorsal aorta in the trunk.

结果从受精卵胚胎发育第12小时可见血管内皮细胞生长因子和血管发生素1及其相应受体flk1和Tie2的表达；在受精卵胚胎发育的第16小时，血管内皮细胞生长因子和血管发生素1主要在头部和尾部胚芽表达；第24小时在眼球、视窝、中脑、后脑的腹前侧和肌节中表达，Tie2和Flk1主要在肌间背部动脉血管、躯干新生血管芽和轴向静脉中表达。

Experiments were also performed to study the IIF behavior of microcapsules of various sizes by the cryomicroscope. It was observed that the microcapsules behaved as osmometers that water migrated across the cell wall when there was an osmotic potential. During freezing, IIF phenomenon of microcapsules occurred immediately after the ice front touched the microcapsule following the seeding of the supercooled solution.

在本研究中亦以褐藻酸钠为材料制作不同大小微胶囊以模拟人工细胞，并以低温显微镜系统进行其低温冷冻实验，实验结果显示微胶囊会因为内外渗透压不同而发生水分迁移现象，且当触发囊壁外过冷水溶液时，囊壁外冰晶形成会随即造成微胶囊发生细胞内冻结现象。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。