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181.
应用大体解剖学和组织学方法探讨中国西北、华北地区特有动物--双峰驼眼球及其附属器官的解剖组织学特点,为特有资源的保护和开发研究提供一定的理论依据.结果表明:双峰驼具有2~5行睫毛和双层眼睑.骨性眼眶夹角约为95~105°.眼肌有四条直肌、两条斜肌、一条上提睑肌和漏斗肌.双峰驼泪腺呈不规则三角形,角膜高度角质化,视网膜为典型的十层结构.双峰驼眼的主要结构与其他脊椎动物类似,在形态学特点和组织学结构方面与其生长的荒漠、半荒漠环境相适应. 相似文献
182.
果蝇唾腺染色体观察实验教学的改革与探索 总被引:1,自引:0,他引:1
果蝇唾液腺染色体观察实验中,传统的方法因为种种原因效果较差。根据长期的教学实践,对该实验作了一些改革与探索。实践证明,改革后实验材料易获得,步骤简洁,所制装片清晰,取得较好的效果。 相似文献
183.
在离子液体四氟硼酸1-丁基-3-甲基咪唑(fBrnim]BF4)和NaH2PO4形成的双水相体系中,研究茜素红S(ARS)与牛血清白蛋白(BSA)生成复合物光谱行为和溶液酸度,盐浓度,离子液体用量,共存物质等对体系复合物测定影响.离子液体用量1.5 mL,磷酸二氢钠2.0 g,ARS 1.0 mL,蛋白质溶液1.0 mL,pH 6时ARS与BSA复合物吸光度较大.离子液相中复合物最大吸收波长位于531 nm,比单纯ARS红移109 nm;摩尔吸光系数(ε)为2.32×104L·mol-1·cm-1.用加入不同类型表面活性剂方法,初步探讨了ARS与BSA之间的作用机理.使用后的离子液体经过简单处理可以重复使用. 相似文献
184.
Summary Recent work concerning the number, site(s) and means of adjustment to the 24-h day of internal clocks is reviewed. Work on humans is considered wherever possible though much of the work involving ablation and in vitro techniques necessarily involves other species, particularly rodents. It is concluded that, though recent advances have been impressive and present techniques appear likely to continue to produce results and stimulate discussion, more attention should be directed to considering the circadian system as a whole rather than as an assemblage of individual components. 相似文献
185.
唾液腺素、羧甲基壳聚糖、低分子壳聚糖对豚鼠齿龈炎的疗效 总被引:3,自引:0,他引:3
针刺豚鼠牙龈,并用1%正丁酸涂抹伤口引起炎症,分别用2%唾液腺素、2%羧甲基壳聚糖(CMCTS)、2%低分子壳聚糖(LMCTS)和蒸馏水涂抹伤口引起炎症研究对齿龈炎的疗效。结果表明:唾液腺素、羧甲基壳聚糖(CMCTS)、低分子壳聚糖(LMCTS)对齿龈炎都有一定程度的疗效。 相似文献
186.
187.
利用UV Vis光谱的方法,系统的研究了银胶溶液与HSA的结合情况.通过研究不同pH条件下,银胶溶液的聚集情况,计算出银胶溶液聚集的热力学参数和动力学参数.证明在pH≤7的溶液中,银胶颗粒与血清白蛋白之间主要是通过离子键形成缔合物,使整个银胶溶液表现出蛋白质的性质,阻止了银胶溶液的聚集.在pH>7的条件下,银胶颗粒与血清白蛋白之间主要是依靠范德华力结合在一起的,血清白蛋白起桥联作用,使银胶颗粒之间形成疏松的缔合物,加速了银胶溶液的聚集. 相似文献
188.
《Journal of Natural History》2012,46(1-2):35-58
The dorsal abdominal scent glands of nymphs in Lygaeoidea are diverse. Some related characters, such as number and distribution of dorsal abdominal scent gland openings (DSOs), and shapes of dark plates surrounding DSOs have been commonly used in taxonomic and/or phylogenetic studies of Lygaeoidea. However, comparative studies of the cuticular fine structures surrounding the DSOs in lygaeoid (and other Heteroptera) nymphs are few. We examined the cuticular fine structures surrounding DSOs of fifth‐instar nymphs of 25 species in seven families of Lygaeoidea with scanning electron microscopy. The results showed that the structures surrounding DSOs, such as distribution pattern of cell network, type of network, type of non‐latticed area, pattern of channels for glandular secretion, are complicated and diverse at the family level, indicating that they are valuable in taxonomic and phylogenetic analyses. 相似文献
189.
《Journal of Natural History》2012,46(2):331-348
Summary The larval development of Argulus coregoni from the first to the ninth stage was studied, with special reference to the morphological changes of the appendages and some other parts of the body. A newly hatched larva is a copepodid-form measuring 0·6–0·7 mm long and approaches the shape of the adult after moulting into the second stage (0·7–0·9 mm). Throughout the larval stages, the first maxilla shows the most remarkable modification. The larvae of the first to the fifth stage are equipped with two strong, curved claws, which act as a clasping organ, at the terminal segment of the first maxilla. The basal segment expands considerably at the third stage (0·9–1·1 mm) prior to forming a sucker at the sixth stage (1·7–2·2 mm). The claws start to degenerate at the fifth stage (1·4–1·8 mm), but are still recognizable as a rudiment after the seventh stage (2·2–2·6 mm). The other distinct morphological changes that occurred are: (1) bifurcation of the anterior part of the dorsal ridges on the carapace, (2) development of the male accessory copulatory organ at the basal segments of the second to the fourth legs, (3) number of posteriorly directed minute spines on the ventral surface of the carapace, (4) number of elements in the supporting ribs of the suckers, (5) number of spines found at the first segment of the second maxilla, and (6) number of setae on the four pairs of thoracic legs. The larval forms of A. coregoni younger than the fourth stage (1·1–1·4 mm) are indistinguishable from those of A. japonicus and A. foliaceus. 相似文献
190.