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1.
用组织化学方法研究了胰阔盘吸虫(Eurytremapancreaticum)尾蚴体内各器官组织的化学成分结果表明,其体内含有糖原、粘蛋白、蛋白质、脱氧核糖核酸DNA及核糖核酸RNA等物质.讨论了其粘液腺及穿刺腺的生理功能.  相似文献   
2.
在内蒙古呼伦贝尔草原检获土耳其斯坦东毕吸虫幼虫期发育程度各不相同的阳性萝卜螺,通过组织学和组织化学方法对其幼虫期进行了观察. 参考周述龙(1991)对日本血吸虫尾蚴幼虫期进行的分期,把土耳其斯坦东毕吸虫的尾蚴发育过程也分为 5 期,尾蚴发育的胚细胞期、胚球期、尾蚴雏体期、尾蚴成熟前期和尾蚴成熟期. 子胞蚴育腔内胚细胞分裂,形成胚球,胚球中出现体细胞和胚细胞的分化,胚细胞结合疏松,胞浆中含酸性粘液和大量汞溴酚蓝反应阳性的碱性蛋白成分. 尾蚴成熟前后在三种腺体的呈色反应方面和日本血吸虫相似,其后钻腺腺体部分 P A S反应呈阳性的含糖类物质在雏体期后期开始分泌,逐渐由腺管通向头器末端. 两种尾蚴在尾蚴的体实质部分,对 P A S和汞溴酚蓝反应的呈色结果有着较大的差异. 另外,通过扫描电镜对土耳其斯坦东毕吸虫的尾蚴进行了比较观察,它们在头器的结构、体棘的形态以及感觉器的分布上存在着一定的差异.两种血吸虫的相似性表明在系统演化上有着密切的联系.  相似文献   
3.
采用一系列组织化学方法,较全面地揭示了黑线仓鼠睾丸组织曲细精管中各期生精细胞的组织化学特点及其与生精能力的关系,提出了糖原细胞分裂同步化程度和精子的PAS反应强弱程度可分别作为衡量睾丸组织生精能力和精子受精能力大小的指标.  相似文献   
4.
Different histochemical techniques were applied to examine the morphological features of the secretory cells of hypopharyngeal glands in the wasp Polistes versicolor. The results showed that most analyzed individuals present active glands with secretion stored in the cytoplasm. In some glands, morphological analyses revealed the presence of degenerative characteristics. Analyses of cellular integrity, however, did not detect dead cells. The results showed that, in P. versicolor, the development and regression of the hypopharyngeal glands were not age related, unlike glands of social bees.  相似文献   
5.
Comparative studies on the nervous system revealed that nitric oxide (NO) retains its function through the evolution. In vertebrates NO can act in different ways: it is released solely or as a co-transmitter, released from presynaptic or postsynaptic site, spreads as a volumetric signal or targets synaptic proteins. In invertebrates, however, the possible sites of NO release have not yet been identified. Therefore, in the present study, the subcellular distribution of the NO synthase (NOS) was examined in the central nervous system (CNS) of two gastropod species, the terrestrial snail, Helix pomatia and the pond snail, Lymnaea stagnalis, which are model species in comparative neurobiology. For the visualization of NOS NADPH-diaphorase histochemistry and an immunohistochemical procedure using a universal anti-NOS antibody were applied. At light microscopic level both techniques labeled identical structures in sensory tracts ramifying in the neuropils of central ganglia and cell bodies of the Lymnaea and Helix CNS. At ultrastructural level NADPH-d reactive/NOS-immunoreactive materials were localized on the nuclear envelope and membrane segments of the rough and smooth endoplasmic reticulum, as well as the cell membrane and axolemma of positive perikarya. NADPH-d reactive and NOS-immunoreactive varicosities connected to neighboring neurons with both unspecialized and specialized synaptic contacts. In the varicosities, the majority of the NADPH-d reactive/NOS-immunoreactive membrane segments were detected in round and pleomorph agranular vesicles of small size (50–200 nm). However, only a small portion (16%) of the vesicles displayed the NADPH-d reactivity/NOS-immunoreactivity. No evidence for the postsynaptic location of NOS was found. Our results suggest that the localization of NADPH-diaphorase and NOS is identical in the snail nervous system. In contrast to vertebrates, however, NO seems to act exclusively in an anterograde way possibly released from membrane segments of the presynaptic transmitter vesicle surface. Based on the subcellular distribution of NOS, NO could be both a volume and a synaptic mediator, in addition NO may function as a co-transmitter.  相似文献   
6.
The anatomical and histochemical study of young and adult endocarps of Argania spinosa (sampled from Tindouf; Algeria) shows a general structure that is similar to that of majority of stone fruits. These samples consist of tissues that contain lignified and cellulosic cell walls. The majority of the tissues are composed of sclerenchyma cells; with very thick lignified cell walls and conducting tissues. Coniferyl lignins are abundant in the majority of the lignified tissues. However, the coniferyl lignins appear at the primary xylem during lignification. Syringyl lignins are present in small quantities. The electron microscopy observation of the sclerenchyma cell walls of the young endocarp shows polylamellate strates and, cellular microfibrils in arced patterns. This architecture is observed in the cell walls of the adult endocarp only after the incubation of the tissue in methylamine. These configurations (arcs) are the result of a regular and complete rotation with a 180° variation in the microfibril angle; the complete and symmetrical arcs show a helicoidal mode of construction. The observation of the sclerenchyma cells revealed the capacity of helicoidal morphogenesis to adjust itself under the influence of topological constraints, such as the presence of a large number of pit canals, which maintain symplastic transport.  相似文献   
7.
Reference is usually made to the parallel orientation towards the main line of exerted tension at the pubic joint in mice, for supporting forces applied to the joint. Despite the wealth of morphological information about the extracellular matrix in this joint, little is known regarding the involvement of the crimp of collagen fibers in the dramatic transformations occurring in this region during the last 3 days of pregnancy. Examination of the collagenous architecture suggests that the biomechanical properties are directly related to fibril diameters, composition of ground substance and changes in the bundle morphology, particularly in the crimp structure. The purpose of this study was to further describe the transformation of the collagen fibers of the pubic symphysis during late mouse pregnancy. We examined the architecture of collagen fibers in the symphysis and pubic ligament through the Picrosirius-polarization method and also through scanning electron microscopy to directly visualize and measure the crimping from pregnant and virgin mice. The crimp angle and the length of five consecutive crimps were measured according to Patterson-Kane et al. [Connect. Tissue Res. 36 (1997) 253]. It could be demonstrated that the angles progressively decreased and the crimp length increased, denoting that the fibers have untwisted during the relaxation process. Our findings suggest that a disruption of the helical arrangement of the collagen containing fibers may contribute to explaining the rapid remodeling that occurs at the end of pregnancy and that is responsible for an increase in pliancy and length of the pubic ligament in mice.  相似文献   
8.
Staining methods applied to glycol methacrylate embedded tissue sections   总被引:2,自引:0,他引:2  
The use of glycol methacrylate (GMA) avoids some technical artifacts, which are usually observed in paraffin-embedded sections, providing good morphological resolution. On the other hand, weak staining have been mentioned during the use of different methods in plastic sections. In the present study, changes in the histological staining procedures have been assayed during the use of staining and histochemical methods in different GMA-embedded tissues.

Samples of tongue, submandibular and sublingual glands, cartilage, portions of respiratory tract and nervous ganglion were fixed in 4% formaldehyde and embedded in glycol methacrylate. The sections of tongue and nervous ganglion were stained by H&E. Picrosirius, Toluidine Blue and Sudan Black B methods were applied, respectively, for identification of collagen fibers in submandibular gland, sulfated glycosaminoglycans in cartilage (metachromasia) and myelin lipids in nervous ganglion. Periodic Acid-Schiff (PAS) method was used for detection of glycoconjugates in submandibular gland and cartilage while AB/PAS combined methods were applied for detection of mucins in the respiratory tract. In addition, a combination of Alcian Blue (AB) and Picrosirius methods was also assayed in the sublingual gland sections.

The GMA-embedded tissue sections showed an optimal morphological integrity and were favorable to the staining methods employed in the present study. In the sections of tongue and nervous ganglion, a good contrast of basophilic and acidophilic structures was obtained by H&E. An intense eosinophilia was observed either in the striated muscle fibers or in the myelin sheaths in which the lipids were preserved and revealed by Sudan Black B. In the cartilage matrix, a strong metachromasia was revealed by Toluidine Blue in the negatively-charged glycosaminoglycans. In the chondrocytes, glycogen granules were intensely positive to PAS method. Extracellular glycoproteins were also PAS positive in the basal membrane and in the region occupied by the lamina externa and reticular fibers surrounding each smooth muscle cells of the blood vessels. In the epithelial cells of the respiratory tract, acid and neutral mucins were histochemically detected by AB and PAS methods, respectively. Moreover, granules containing acid and neutral mucins were revealed in purple by AB and PAS concomitantly. In the sublingual gland sections, a distinct affinity of acid mucins by AB (in turquoise-blue) and collagen fibers by Picrosirius (in red) was obtained when these methods were combined. Although some routine dyes used in paraffin sections have showed a weak stain in historesin sections, our results showed that different dyes could be applied in GMA sections if modified staining procedures were assayed. Therefore, appropriate staining contrast and, thus, detection of one or different substances in a same section can be acquired in association to the good morphological resolution provided by GMA.  相似文献   

9.
本文对小麦茎生长锥分化及花和花序发育过程中细胞内物质的变化进行了研究。其变化规律可总结为以下两方面:(1)DNA,RNA 和蛋白质分布的细胞区域基本一致,且都在发生新器官和迅速生长发育的原分生组织细胞中含量最丰富。(2)淀粉物质的大量积累都是向着迅速生长与发育的新器官方面转移,而且积累淀粉的细胞区域总是紧靠在原分生组织的后面,但不在原分生组织细胞中,穗轴上不同部位小穗及小穗上不同部位小花的发育状况与所获得的营养物质(主要是多糖)成正相关。  相似文献   
10.
During Isoptera evolution, the caste of soldiers disappeared in some Apicotermitinae termites as in the Neotropical Ruptitermes. Paired dorsolateral structures located between the metathorax and abdomen of foraging workers of Ruptitermes were previously denominated dehiscent glands, and are responsible for releasing an adhesive secretion that immobilizes enemies, causing their death. In this study, we investigated the morphology of dehiscent organs of workers of Ruptitermes reconditus, Ruptitermes xanthochiton, and Ruptitermes pitan and also second instar larvae of R. reconditus using light, laser scanning confocal, and transmission electron microscopy. Additionally, we performed a preliminary protein analysis using SDS-PAGE to further characterize the secretion of Ruptitermes dehiscent organs. Our results showed that the dehiscent organs do not exhibit the typical characteristics of the exocrine glandular cells class I, II or III of insects, suggesting that they constitute a new type of defensive organ. Thus, the denomination dehiscent gland was not used but dehiscent organ. Dehiscent organs in larvae are formed by fat body cells. In workers, dehiscent organs are composed by compact masses of cells that accumulate a defensive secretion and are poor in organelles related to the production of secretion. Since the dehiscent organs are not glands, we hypothesize that the dehiscent organs originate from larval fat body. The defensive secretion may have been produced at younger developmental stages of worker or the defensive compounds were absorbed from food and accumulated in the worker fat body. Histochemical techniques and SDS-PAGE revealed that the secretion of Ruptitermes dehiscent organs is constituted mainly by a protein of high molecular weight (200 kDa). In conclusion, the dehiscent organs are extremely different from the exocrine glands of termites and other insects described until now. In fact, they seem to be a specialized fat body that is peculiar and exclusive of Ruptitermes termites.  相似文献   
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