日本三角涡虫组织结构嗜银反应观察

涡虫在动物系统演化史上占有十分重要的地位,雌雄同体,具有很强的再生能力,因此,对其组织结构嗜银反应进行研究具有重要的意义.本文用Grimellus还原银法显示了日本三角涡虫(Dugesia japonica)嗜银反应阳性的组织结构.结果表明:肠上皮细胞内有很多染成棕褐色的圆形泡状结构,肠上皮下的实质组织细胞中分布很多黑色颗粒;交配囊上皮细胞可见染成棕褐色的颗粒;在雄腔和交配囊柄两侧和后部可见染成棕褐色的三角形区域;纵神经索嗜银反应较弱,呈浅褐色.因此,可以确定肠上皮下实质组织中存在APUD系统.     

九孔鲍血细胞的研究

采用May Grunwald-Giemsa染色法研究九孔鲍(Haliotis diversicolor supertexa)血细胞的显微结构,根据细胞大小和核质比将九孔鲍血细胞分为3类:大细胞、中等细胞和小细胞.血细胞密度为(8.32±4.76)×106/mL,大细胞、中等细胞和小细胞分别占血细胞总数的3.6%、91.7%和4.7%.透射电镜下血细胞可分为两类:颗粒细胞对应于光镜下的大细胞和中等细胞;无颗粒细胞对应于光镜下的小细胞.用细胞化学的方法证明九孔鲍血细胞中含有多糖、酸性磷酸酶、非特异性酯酶和过氧化物酶,它们的阳性率分别为57.3%、95.2%、86.3%、6.7%;但是根据血细胞的这几种成分不能区分血细胞的类型.     

16Mn合金无缝钢管在山区高水头管引工程的应用

山区管引工程地形复杂,大都具有坡陡谷深、高水头、小流量的特点,对管材的选择和接头处理要求较高,16Mn合金无缝钢管屈服点σs=300-400N/mm2,[σ]可达到150-200N/mm2,屈服点和允许应力较普通钢管和PE管较高。通过永平县普棚下大沟改建工程倒虹吸的设计施工和运行效果看,16Mn合金无缝钢管可作为我们优化设计的一种方法,在山区高水头管引工程中应用的推广。     

盐穴储气库建腔期边界区域流场的模化实验研究

为了解盐穴储气库建腔阶段中心管、外管循环流体所产生的对流扩散运动对盐腔壁区域流场速度的影响,运用相似模化原理建立了相似模型,采用粒子图像测速系统(PIV)和Fluent数值模拟软件,对不同条件下建腔阶段的边界附近流场进行测试与数值模拟。结果表明,正循环下,底部边界受到的流体对流扩散的影响要大于侧壁边界,在本模型中对距离盐腔侧壁边界0.2m区域内流场速度影响非常小;反循环下,随外管的提升,对流扩散的主要影响区域发生变化,并且边界区域流体速度也随对流扩散的主要影响区域而变化;在反循环下,缩短外管长度和增大流量都会使得边界区域流体速度增大,但两者主要影响的边界区域范围有所不同。数值模拟和实验得出的结论吻合度较高。本实验结果对提高盐穴储气库建腔效率有一定的参考价值。     

水溶性富勒烯衍生物的合成

给出用电化学反应和加成反应合成水溶性多羟基富勒烯衍生物褐色晶体的方法.通过研究分析其红外吸收谱、快原子轰击电离质谱和1H及13C核磁共振谱,发现该衍生物为富勒醇.该衍生物能在水中及空气中长时间稳定存在,在25℃下在水中的溶解度大于100mg/mL.     

两种黑色素细胞染色法的介绍

黑色素细胞在正常情况下分散在皮肤、毛发、眼虹膜及脉络膜等器宫内。皮肤的黑色素细胞位于表皮基底细胞之间,无细胞间桥和张力原纤维,胞浆透亮,核小而色深,有长的胞浆树突(图1),能产生或制造黑色素。在某些病理情况下,例如由于黑色素细胞的增生或功能亢进等原因。所引起的良性或恶性的病变,种类较多,在病理诊断中常带来一定的困难,单用一般常规H.E.染色较难确诊,必须选择特异性强,操作较为方便的方法才行。按黑色素是一种蛋白衍生物,呈褐色     

8mm雪崩管过模功率合成器

本文介绍了1种四管IMPATT二极管功率合成电路。采用矩形谐振腔合成技术已成功地使用在毫米波IMPATT二极管功率合成。谐振腔是用过膜(尺寸)波导腔。过尺寸波导腔的使用增加了二极管之间的纵向距离,减小了在很高频率时机械尺寸的要求。合成单元是使用交叉的同轴——波导耦合的二极管支持结构。腔的两端由膜片和1个可调的短路器形成。这腔容易与标准波导耦合。由于矩形波导的不连续性,存在模的转换损耗。实验中获得了功率合成输出,并且有较高的功率合成效率。     

基于自聚焦微透镜的内窥镜诊疗系统设计

内窥镜是医学微创手术的首选设备,而基于自聚焦微透镜的内窥镜因能达到传统光学及电子内镜无法满足5mm以下管腔微创手术的要求,又可最大限度减少患者痛苦和手术风险而成为内镜发展的主流趋势。利用0.1mm～3mm的自聚焦微透镜核心技术研制新一代超细内镜诊疗设备系列产品,其外径0.9mm～8mm,可作为妇科医生常规检查的新式武器——＂看诊器＂,用于阴道、宫腔及输卵管疾病的无创及微创诊疗,是传统光学宫腔镜的升级换代产品,并可向血管、胆管、眼科等各种细小管腔疾病的微创诊疗产品延伸。     

棕色脂肪组织银染实验

通过改进龙桂开银染方法对休眠期刺猬褐色脂肪组织进行染色实验,结果表明适当改进的龙桂开银染方法能够使褐色脂肪组织染出良好的效果,并在银染的休眠期刺猬褐色脂肪组织观察中发现,休眠期刺猬褐色脂肪组织细胞内有核仁,并多为1～4个,这与常规描述不一致。     

鲎血淋巴系统的特点及其功能

鲎的血淋巴系统由心脏、血管和血淋巴液组成．心脏和血管系统非常发达，而且血液量巨大．血淋巴液由血浆和血细胞组成．血浆主要含有血蓝蛋白、02—巨球蛋白、C—反应蛋白等．对鲎血细胞的种类，看法不一，其主要的血细胞类型为颗粒性血细胞，其胞质中含有特征性的大小颗粒．鲎的血淋巴中含有50种以上的免疫因子，大都位于大小颗粒中，它们在鲎的天然免疫中起重要的作用．     

The distribution of integumentary structures in a feathered dinosaur

Non-avian theropod dinosaurs with preserved integumentary coverings are becoming more common; but apart from the multiple specimens of Caudipteryx, which have true feathers, animals that are reasonably complete and entirely articulated that show these structures in relation to the body have not been reported. Here we report on an enigmatic small theropod dinosaur that is covered with filamentous feather-like structures over its entire body.     

Basal tyrannosauroids from China and evidence for protofeathers in tyrannosauroids

Tyrannosauroids are one of the last and the most successful large-bodied predatory dinosaur groups, but their early history remains poorly understood. Here we report a new basal tyrannosauroid from the Early Cretaceous Yixian Formation of western Liaoning, China, which is small and gracile and has relatively long arms with three-fingered hands. The new taxon is the earliest known unquestionable tyrannosauroid found so far. It shows a mosaic of characters, including a derived cranial structure resembling that of derived tyrannosauroids and a primitive postcranial skeleton similar to basal coelurosaurians. One of the specimens also preserves a filamentous integumentary covering similar to that of other coelurosaurian theropods from western Liaoning. This provides the first direct fossil evidence that tyrannosauroids had protofeathers.     

Forensic palaeontology: The Archaeoraptor forgery

The Archaeoraptor fossil was announced as a 'missing link' and purported to be possibly the best evidence since Archaeopteryx that birds did, in fact, evolve from certain types of carnivorous dinosaur. It reportedly came from Early Cretaceous beds of China that have produced other spectacular fossils transitional between birds and extinct non-avian dinosaurs. But Archaeoraptor was revealed to be a forgery in which bones of a primitive bird and a non-flying dromaeosaurid dinosaur had been combined. Here we use high-resolution X-ray computed tomography (CT) to determine the nature and extent of the forgery, as well as how it was built, by imaging the fracture pattern and distribution of materials through the entire specimen.     

Fine structure of bone in dinosaurs, birds and mammals

After observation of detailed structural evidence for the origin of birds from dinosaurs, and in light of evidence that dinosaur bone tissue resembles the histology in mammals, the histology of bone has become one of the focal points in discussions of the physiology of dinosaurs and Mesozoic birds. Most of this microstructural information has focused on features related to the vascular organization and the amount of remodelled bone around vascular canals. However, the finer structures have received less attention, although differences in such structures have been observed among modern vertebrates. Here we present evidence that canaliculi--the submicrometre-sized channels that interconnect bone cells and vascular canals--and the collagen fibre bundles in bone are differently organized among certain dinosaur lineages. Ornithomimid dinosaurs are more like birds than mammals in these features. In canalicular structure, and to some extent in fibre bundle arrangement, ornithischian dinosaurs are more like mammals. These differences in both canalicular and lamellar structure are probably linked to differences in the process and rate of bone formation.     

Baryonyx, a remarkable new theropod dinosaur

An extremely large claw bone, some 30 cm long, was found in Wealden (Lower Cretaceous) deposits in a Surrey claypit in January 1983. This led to the discovery the following month of the well-preserved skeleton of a new large theropod dinosaur. Only one other theropod specimen comprising more than a few bones had ever been found in Britain, and that discovery was more than a century ago. Indeed, no large theropod, reasonably complete, had previously been discovered in Lower Cretaceous rocks anywhere in the world. Our study so far suggests that the Surrey dinosaur was a typical large theropod in certain respects, resembling, for example Allosaurus. In several other respects, however, it differs sufficiently from all known dinosaurs to merit designation as the representative of a new species, genus and family.     

鳖的肝脾是免疫器官

取鳖的各类骨,肝,脾制成切片进行研究。结果发现：鳖骨髓不造血,肝内的淋巴组织多为成熟的中、小淋巴细胞,少数为分裂状态的淋巴细胞和浆细胞,肝实质内,肝窦内及靠近肝内的血管处,各期各类的血细胞丰富;脾脏内的脾小体中,越靠近中心淋巴细胞,其核仁越清晰,细胞核的结构越疏松,细胞的分裂现象越明显,脾索内发现有巨噬细胞,网状细胞,浆细胞,成熟和幼稚的各种血细胞等,因此说,肝和脾是鳖的免疫器官。     

A new carnivorous dinosaur from the Late Jurassic Solnhofen archipelago

Small Late Jurassic theropod dinosaurs are rare worldwide. In Europe these carnivorous dinosaurs are represented primarily by only two skeletons of Compsognathus, neither of which is well preserved. Here we describe a small new theropod dinosaur from the Late Jurassic period of Schamhaupten in southern Germany. Being exquisitely preserved and complete from the snout to the distal third of the tail, the new fossil is the best-preserved predatory, non-avian dinosaur in Europe. It possesses a suite of characters that support its identification as a basal coelurosaur. A cladistic analysis indicates that the new taxon is closer to maniraptorans than to tyrannosauroids, grouping it with taxa often considered to be compsognathids. Large portions of integument are preserved along its tail. The absence of feathers or feather-like structures in a fossil phylogenetically nested within feathered theropods indicates that the evolution of these integumentary structures might be more complex than previously thought.     

A primitive therizinosauroid dinosaur from the Early Cretaceous of Utah

Therizinosauroids are an enigmatic group of dinosaurs known mostly from the Cretaceous period of Asia, whose derived members are characterized by elongate necks, laterally expanded pelves, small, leaf-shaped teeth, edentulous rostra and mandibular symphyses that probably bore keratinized beaks. Although more than a dozen therizinosauroid taxa are known, their relationships within Dinosauria have remained controversial because of fragmentary remains and an unusual suite of characters. The recently discovered 'feathered' therizinosauroid Beipiaosaurus from the Early Cretaceous of China helped to clarify the theropod affinities of the group. However, Beipiaosaurus is also poorly represented. Here we describe a new, primitive therizinosauroid from an extensive paucispecific bonebed at the base of the Cedar Mountain Formation (Early Cretaceous) of east-central Utah. This new taxon represents the most complete and most basal therizinosauroid yet discovered. Phylogenetic analysis of coelurosaurian theropods incorporating this taxon places it at the base of the clade Therizinosauroiden, indicating that this species documents the earliest known stage in the poorly understood transition from carnivory to herbivory within Therizinosauroidea. The taxon provides the first documentation, to our knowledge, of therizinosauroids in North America during the Early Cretaceous.     

多电极电磁流量计肢体血液流速分布测量研究

为实现人体血液流速分布的非侵入式测量,对重大心血管疾病进行预判,将多电极电磁流量计应用于人体肢体血液速度剖面测量,将传统Shercliff权函数改进为区域权函数,模仿人体肢体结构建立COMSOL仿真模型,将测量截面划分为不同区域,通过多对电极获取不同位置的弦端电压,确定肢体截面上不同测量区域的权函数,进而计算各测量区域的局部轴向平均速度。针对动脉、静脉所在位置范围内进行不同区域划分并进行血液流速分布测量,仿真验证了多电极电磁测量系统对动脉、静脉血管中互为逆向流动的速度信息测量的可行性。三维有限元仿真和计算结果表明,所提出的测量方法能够实现肢体测量截面处不同方向的流速测量,并且具有较高的速度分布重构精度,对于人体血液流速测量和血流变异常监测具有参考价值。     

Branched integumental structures in Sinornithosaurus and the origin of feathers

The evolutionary origin of feathers has long been obscured because no morphological antecedents were known to the earliest, structurally modern feathers of Archaeopteryx. It has been proposed that the filamentous integumental appendages on several theropod dinosaurs are primitive feathers; but the homology between these filamentous structures and feathers has been disputed, and two taxa with true feathers (Caudipteryx and Protarchaeopteryx) have been proposed to be flightless birds. Confirmation of the theropod origin of feathers requires documentation of unambiguously feather-like structures in a clearly non-avian theropod. Here we describe our observations of the filamentous integumental appendages of the basal dromaeosaurid dinosaur Sinornithosaurus millenii, which indicate that they are compound structures composed of multiple filaments. Furthermore, these appendages exhibit two types of branching structure that are unique to avian feathers: filaments joined in a basal tuft, and filaments joined at their bases in series along a central filament. Combined with the independent phylogenetic evidence supporting the theropod ancestry of birds, these observations strongly corroborate the hypothesis that the integumental appendages of Sinornithosaurus are homologous with avian feathers. The plesiomorphic feathers of Sinornithosaurus also conform to the predictions of an independent, developmental model of the evolutionary origin of feathers.