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1.
<正>当窗外猫头鹰的"咕咕"声和外公的呼噜声配成一首滑稽的奏鸣曲,我知道,夜已经很深了。穿好衣服,提上鞋子,我蹑手蹑脚地溜出家门。今晚,对,趁着夜深人静,我要独自走入森林,找到外公提到过的那棵老橡树。哪怕田鼠啃咬我的脚趾,虫虫钻进我的衣领,我都会在树下屏住呼吸,耐心守候,因为……  相似文献   

2.
爱尔兰多尼戈尔郡郊外,一座名叫贝利的宏伟庄园内。庄园主帕克先生站在巨大的落地玻璃窗前,用食指和大拇指轻轻捏着餐巾一角,优雅从容地抹掉嘴边的一丁点儿花生酱。我的庄园怎么样?尊敬的朱莉小姐!帕克转过身,对身边一位戴着鸟羽装饰帽,衣着华贵的漂亮女士说道。恕我直言,帕克先生。朱莉耸耸肩,您的庄园很美,有花草,有庭院,有骏马,有天鹅,但依我看,它太过柔美了。我听说,在都柏林,时髦的绅士们喜欢给自己的庄园加些野性力量。您知道,温克  相似文献   

3.
走进内蒙     
孙丹辉 《化石》2016,(1):61-65
2015年8月1日,我们每一个人收拾好行囊,整装待发,在邓涛老师带领下踏上了去往内蒙古的征程,拉开了探索灰色生命之旅的序幕. 队伍由两辆车、8人组成,我们早晨7点从中国科学院古脊椎动物与古人类研究所出发,披着清晨的阳光,摆脱城市的拥挤,缓缓地“逃离”了北京城.直到抵达张北之后我们的车子才能像矫健的马儿一样驰骋在广袤的公路上,沿途没有了城市的喧闹,没有了交通的堵塞,伴随我们的只有那一眼望去蓝蓝的天空、随风摆动的小草,以及那迷人的风景,偶尔打开车窗,一股凉爽的清风扑面而来,沁人心脾.经过一路的颠簸,我们在傍晚时刻到达锡林浩特,当地文物保护站的同志为我们安顿好了一切.  相似文献   

4.
赵福瑜 《化石》2007,(3):19-21
地球上十二属种动物与人类的关系存在决定意识,人们的社会存在决定人们的社会(思想)意识。人类产生“十二兽”观念并制订,实行十二兽历法,正是人类自身起源于“十二兽”的先祖这一客观事实在人们头脑中的反映。十二兽:我国又称十二禽,十二属,十二物,十二生肖等。所谓十二兽,我国汉族是指鼠,牛,虎,兔,龙,蛇,马,羊,猴,鸡,狗,猪。让我们从十二兽历法的产生和起源来探讨地球上十二属种动物(十二兽)的先祖与人类进化的关系。世界上四大文明古国———中国、印度、埃及和巴比伦各有其“十二兽历法”,内容上大同小异。中国汉族:鼠,牛,虎,兔,龙,蛇,…  相似文献   

5.
无聊的寒假,无聊的阿拉斯加,没有电子游戏,没有小伙伴,最讨厌的是……阿,阿嚏!这鬼天气简直要把人冻成冰棍。一下飞机,盖瑞就在心里一个劲儿地抱怨。为了写一本关于鹰的书,盖瑞的作家老妈带着他,哦不,应该是硬拽着他来到了偏远的阿拉斯加,美其名曰:在冰天雪地中亲近自然。  相似文献   

6.
马志朝  何烈琪  林伟南  刘玮 《蛇志》2008,20(1):17-19
目的 通过对容县2000~2007年84例狂犬病流行病学特点进行分析,探讨流行回升的因素,分析目前防治过程中存在的问题,提出狂犬病的预防对策和措施.方法 收集2000~2007年容县狂犬病疫情报告资料及对狂犬病病例的个案调查资料进行分析.结果 近年来,容县狂犬病疫情明显上升,成为有史以来流行高峰,最高年发病率3.04/10万.发病以农民,学生为主,男性多于女性,全年均有病例发生,无明显季节性,狂犬病暴露动物以犬伤为主,暴露部位以头颈部为最危险,潜伏期最短.结论 为有效预防狂犬病流行,应进一步建立完善犬类的管理的法律、法规,使预防狂犬病进入法制轨道,以有效控制狂犬病流行.伤后未能及时正确处理,暴露后免疫率低,是狂犬病发生的重要原因.加强宣传,提高狂犬病的防控知识,政府部门齐抓共管,采取综合性防控措施,才能有效控制狂犬病的流行.  相似文献   

7.
按树是我国南方地区常见的常绿树种,我们经过较长时间的调研和资料整理,认为桉树类的枝叶油与柴油的理化性质十分接近,是非常好的内燃机燃料油的代用品。而且,蒸馏按树油与绿化荒山、培育用材林矛盾不大,建设按树油基地不仅可以解决燃料油的短缺,也可培植用材林,带动地方经济的发展,增加农民收入,是一举多得的事业。  相似文献   

8.
《生命世界》2012,(10):94-95
野生红豆杉,冰川世纪遗留下来的古老树种,以它顽强的生命力屹立在地球上已几百万年。在人类出现在这个星球以前,它就以红彤彤的红豆果,扮靓了地球的山间和密林。它树姿优美,枝繁叶茂,苍劲挺拔,一派生机盎然,令人敬畏。它果实鲜红,艳丽无比,圆如珍珠,寄托相思之情,令人爱怜。它全身是宝,强身健体,防癌抗癌,历史悠久,令人感动。  相似文献   

9.
聆听草语     
碣石山 《生命世界》2005,(4):100-101
出小小的村落,一直往南走,有一片辽阔的草地。任那向阳的坡坝上,长着墨绿色的草儿们。浓浓的,密密的,人丁旺盛,不像园圃那么单调。蒲公英、野艾、沙拉秧、芨芨草、酢浆草、抽筋草、马齿苋、野羊姜……这些草常常迷幻了我的心与眼。我分不清它们的性别,更不甚清楚它们归属哪个"门派"。眼熟的几个叫着名字,剩下的含混着打个招呼,像人群中那些混个脸熟却不知名姓的人一样。在尘世间活得飞扬跋扈时,我去看草。它们平凡地生活着,宽容,谦让,和平友爱的样子,没有专制,也不自以为  相似文献   

10.
说起竹子,人们都会想到南方。这不奇怪,野生的竹子主要分布于秦岭和淮河以南,而北方的竹子,基本都是移栽的。可是,如果时光倒流几千年,你也许会发现,在广袤的中华大地上,在中华民族的发源地——黄河流域,到处都有竹子的分布。  相似文献   

11.
The respiratory epithelium in the lungs of the tortoise (Testudo graeca) has been studied by electron microscopy. The epithelium consists of a mosaic of two different cell types (here called "pneumonocytes"). Type I pneumonocytes are roughly squamous and possess attenuated flanges of cytoplasm which extend over the septal capillaries. Localized cytoplasmic expansions are often present near the periphery of these flanges. Most of the organelles are concentrated in the perinuclear region; the most prominent of these are the mitochondria and osmiophilic inclusions. In contrast, type II pneumonocytes are cuboidal and are richly endowed with organelles including large Golgi complexes, extensive endoplasmic reticulum and numerous inclusion bodies. The morphological evidence suggests that type I pneumonocytes are involved in the secretion of osmiophilic material (presumed to be pulmonary surfactant) and in maintaining the integrity of the air-blood barrier. Type II pneumonocytes appear to be concerned solely with the production of surfactant.  相似文献   

12.
Summary The cells of the sinuatrial ring bundle are smaller than the ordinary myocardial cells; they have a regular outline and a large content of myofibrils exhibiting distinct H-bands and M-lines. Rudimentary T-tubules are found. The cells are connected by frequent nexus junctions, desmosomes and regions of interfibrillar contact, both on the well developed intercalated discs and at the periphery of the cells.The cells in the cauda of the sinus node, which extends alongside the crista terminalis together with the right branch of the sinuatrial ring bundle, are irregularly outlined and have a highly variable diameter (1–10 m). They occur in clusters of closely packed cells. The content of myofibrils is sparse and the fibrils exhibit no M-lines and only weak H-bands. No T-tubules are found. The cells are not connected by intercalated discs and no nexus junctions are found.Both tissues contain unmyelinated nerves and nerve fibres. Varicosities with mitochondria and vesicles are found in close apposition to the muscle cells.  相似文献   

13.
It is 100 years since Gini noted that in some samples of litters of mice and rabbits, the variances of the distributions of the combinations of the sexes are sub-binomial. In other words, in contrast with binomial expectation, there are too many litters in which the sexes are equally balanced, and there are too few unisexual litters. In the intervening years, this finding has been replicated in a number of further species, but no explanation has become established. Potential explanations are reviewed here, and it is suggested that the most likely cause is that, at the time of formation of the zygotes, p, the probability that a zygote will be male, varies from one zygote to another within litters, thus constituting an example of Poisson variation. And it is a standard result in probability theory that such variation causes sub-binomial variance.  相似文献   

14.
200 gall-bladders of goat were studied for histology and histochemistry. The lining epithelium is tall columnar with striated border. The glands are mucous and serous, and the secretion of both surface and glands is a polyssaccharide-protein complex. The regional differences at neck, body and fundus of the gall-bladder are described. Few enterochromaffin cells with granules, which are PAS-positive and contain 5-hydroxytryptamine, are encountered at the wedge between the granular epithelial cells and the cells lining the crypts. The relationship between these cells and lymphocytic infiltration is discussed. The thick circular muscle layer at the neck region is considered a sphincter of the gall-bladder.  相似文献   

15.
Summary In the mouse, the rostral zone of the pars intermedia is almost exclusively composed of typical corticotrophic cells. They are located around and even within the neural stalk, at the level of transition between stalk and neural lobe. In the rat, the corticotrophic cells of the rostral zone are found in scattered islets among the MSH producing cells, and also in the neural lobe. In both the rat and mouse, these cells are in direct contact with various types of nerve terminals. Synaptoid contacts with aminergic and neurosecretory nerve fibers are observed. Furthermore they are also closely related to the hypophysial portal vessels. Following adrenalectomy, the cells located in the neurohypophysis always react more intensely than tose in the rostral zone. The functional significance of these corticotrophic cells which are subject to both humoral and neural regulation remains as yet hypothetical. Their participation in neurogenic stress response seems probable.  相似文献   

16.
From the aspect of its mucopolysaccharide content the mast cell population is not homogeneous. The pulmonary and heart muscle mast cells of the rat are alcian blue positive, the mast cells of the thyroid gland, lymph nodes, subcutaneous connective tissue, mesentery and peripheral nerve are safranin positive, whereas among the mast cells of the peritoneal cavity and the thymus there are both alcian blue and saffranin positive forms. The least acid mucopolysaccharides are in the mast cells of the peritoneal fluid, the mesentery and the lungs, whereas the most acid ones are in the mast cells of the lymph nodes, the subcutaneous connective tissue and the thyroid gland. There is a considerable difference between the two last mentioned organs. The mast cells of the subcutaneous connective tissue are end-product cells without amine or precursor turnover, whereas the mast cells of the thyroid gland incorporate and deliver amines, which may participate in the regulation of the host gland.  相似文献   

17.
In this essay crucial problems of the origin of cancer and the development of malignancy are discussed. The problem of precancer and three ways leading to malignancy are considered: induction of tumor precursors, accumulation of genetic traits common for tumor growth, and the role of inflammation in tumor induction. The nature of viral oncogenes and modes of their action are described in the context of their origin as a component of the viral genome. Oncogenes of RNA-containing viruses and DNA-containing tumorigenic viruses are described together with cellular protooncogenes, which are progenitors of RNA-containing viral oncogenes. Hematological malignancies are described as an intermediate form between simple tumors induced by a single oncogene and more complicated epithelial tumors. The roles of tumor suppressor genes and the interaction of several oncogenes in the formation of carcinomas and also the role of progression in tumor evolution are discussed.  相似文献   

18.
19.
The fundamental ideas of the phoronomics of the entropy are developed. There are some important kinematic quantities and three kinematic decompositiones.  相似文献   

20.
Voigt T  Dauber W 《Tissue & cell》2004,36(4):249-252
In the present investigation the sole plate area of motor end plates of the frog is ultrastructurally examined with different postfixation methods. We concentrated in this case on the proof of the smooth and rough sarcoplasmic reticulum of the sole plate. The relations of the smooth and rough sarcoplasmic reticulum to subsynaptic folds and the local T-system and its connections to diads and triads in the sole plate area are represented. The morphological differences between mammal and frog are pointed out. The possible functions of the sarcoplasmic reticulum in the myofibril-free sarcoplasm are discussed.  相似文献   

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