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1.
Summary The dorsal tegument of the mature cercaria of Notocotylus attenuatus is a syncytial, cytoplasmic layer, containing two types of secretory granule which are identifiable ultrastructurally. The type 1 secretory bodies are electron lucid, whereas most type 2 granules have a banded appearance. The ventral tegument contains granules which are secreted from the type 3 cells; the type 3 granules are membrane bound, electron dense, and consist of both an amorphous and a finely striated zone. The type 4 cells mainly contain cigar-shaped granules consisting of an amorphous core surrounded by concentric striations. The granules exhibit structural variability in shape and content. The type 4 cells undergo a cellular migration to the tegument during encystment. The structure of the posterior-lateral glands and mode of secretion of the granules are described. Possible functions of microtubules are discussed for each cell type. Details of some secretory processes involved in the formation of the hemispherical cyst wall are described. The layers of the cyst wall may be related to the granular contents of the various parenchymal cells of the cercaria. The tegument of the metacercaria originates primarily from the cytoplasm of the type 1, type 2, type 3 and type 4 cells.  相似文献   

2.
兴安杜鹃叶中挥发性成分的GC-MS分析   总被引:1,自引:0,他引:1  
惠宇  孙墨珑 《植物研究》2012,(3):365-368
采用水蒸气蒸馏法对兴安杜鹃叶中的挥发性成分进行提取,并运用气相色谱—质谱联用技术(GC-MS)对其挥发性成分进行了系统的分离和鉴定。从兴安杜鹃叶中共鉴定出54种挥发性成分,占总馏出成分的97.84%。兴安杜鹃叶主要挥发性成分为桉叶醇(eduesmol),相对含量10.95%;β-愈创木烯(β-guaiene),相对含量10.21%;长叶醛(longifolenaldehyde),相对含量7.88%;1,5,9,9-四甲基-1,4,7-环十一碳三烯(1,5,9,9-tetramethyl-1,4,7-cy-cloundecatriene),相对含量7.80%;杜鹃酮(germacrone),相对含量5.91%;(-)-葎草烯环氧化物Ⅱ((-)-HumuleneepoxideⅡ),相对含量5.52%;2-庚基-1,3-二氧戊环(2-heptyl-1,3-dioxolane),相对含量4.99%;石竹烯(caryo-phyllene),相对含量3.70%;(+)-γ-古芸烯((+)-γ-gurjunene),相对含量3.44%。  相似文献   

3.
Zusammenfassung Das Muster in den Calcitindividuen des Eischalenkalkes der Vögel-seine Entstehung wird kurz erläutert — kann durch Spalten, Verwachsungsnähte, Anordnung der Globularinklusionen ohne weiteres hervortreten, läßt sich aber auch durch bestimmte Eingriffe, z. B. Ätzen, verdeutlichen. Quer- und Flachschliffe der Eischale von Diomedea exulans (Albatros) zeigen im Bereich der Säulenlage ein ausgeprägtes Globularmuster:In den Primen der Inneren Säulenlage erscheinen am Querschliff die Inklusionen in Parallelstreifen, die schräg gegen die Schalenoberfläche verlaufen, wobei die Neigung von einem zum anderen Prisma wechselt. Jede Reihe dieses Streifenmusters setzt sich aus rhombischen Elementen zusammen, derart, daß das eine Paar der Rhombenseiten die Längsränder des Streifens liefert, das andere aber, schräg über ihn verlaufend, seine Elemente trennt. Die Girlandenzone der Inneren Säulenlage wird durch den genannten Neigungswechsel des — hier vergröberten — Streifenmusters erzeugt.In der Äußeren Säulenlage häufen sich die Globularinklusionen in rechteckigen oder rhombischen Feldern an, die innerhalb des gleichen Prismas parallel stehen. Die Felder sind durch schmale helle inklusionsfreie Raine getrennt, in denen Verwachsungsnähte sich zeigen können. Dieses Block- oder Rhombenmuster ist auch am Flachschliff sichtbar.Der Übergang vom Streifenmuster der Inneren zum Rhomben- oder Blockmuster der Äußeren Säulenlage vollzieht sich über eine die Elemente durchschneidende Schichtlinie hinweg, ohne Störung der optischen Einheitlichkeit des Prismas. So kann das gleiche Musterelement unterhalb der Schichtlinie das Streifen-, oberhalb derselben das Blockmuster darbieten. Sowohl bei den Inneren wie bei den Äußeren Säulenprismen erfolgt die seitliche Verfugung der Nachbarn unter dem Einfluß des Musters, was bei den Inneren Säulen zackigen, bei den Äußeren mehr glatten Grenzverlauf erzeugt. Oft brechen Musterelemente an den Prismengrenzen ab. Manche Prismen der Inneren Säulenlage erscheinen am Flachschliff rhombisch umrissen. Auch am hügeligen Relief der Schalenoberfläche treten Rhombengrenzen hervor.
Summary The pattern in the calcite individues of the avian egg shell — its development is shortly explained — can appear by clefts, outgrowing sutures, arrangement of the globular inclusions, but also can be rendered conspicuous by certain treatments, e.g. etching. Transverse and tangential ground sections through the egg shell of Diomedea exulans (albatros) show in the column layer a characteristic globular pattern.In the prisms of the inner column layer the inclusions are arranged on transverse sections in parallel stripes, running obliquely against the shell surface, whereby its inclination changes from one to the other prism. Each row of this stripe pattern is composed by rhombic elements, so that one pair of the rhomb sides form the longitudinal edges of the elements but the other, obliquely cutting the stripes, separate the elements. The garland zone of the inner column layer is the expression of the alternating inclination in the stripe pattern — here more coarse.In the outer column layer the globular inclusions are accumulated in rectangular or rhombic areas parallel within the same prism. The elements of this block or rhomb pattern are separated by narrow light inclusion-free hiels, in which outgrowing sutures can appear; the pattern is also visible in tangential ground sections.The transition of the stripe pattern to the rhomb or block pattern happens on a stratification line — without disturbance of the the uniform extinction of the prism between crossed polars. Thereby the same pattern element can show under the stratification line the stripe pattern and above it the block pattern. In the inner as in the outer column prisms the lateral indentation of the neighbours is determined by the pattern, producing in the inner columns a pronged, in the outer a more smooth boundary. Often pattern elements break off at the prism boundaries. Some prisms of the inner column layer show a rhombic contour in tangential ground sections. Also on the hilly relievo of the shell surface rhombic limitation is observable.
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4.
人工种植长春花生物学性状和生物碱含量的季节动态   总被引:1,自引:0,他引:1  
以人工种植的长春花(Catharanthus roseus(L.)G. Don)为材料,研究了一个生长季节内长春花的生物学性状和生物碱含量的季节动态。研究发现,长春花的株高、生物量和叶片数呈现相似的生长趋势,即前期(5~7月)缓慢增长、中期(7~9月)快速增长和后期(9~10月)增长缓慢3个明显的季节生长特征,而花总数在前期和中期也呈现相似的规律,但在后期(9~10月)快速下降。长春花叶片中3 种生物碱含量的季节变化规律明显,变化趋势相一致。3 种生物碱的含量在一个生长季节内均是先增加后降低再增加的趋势,且3 种生物碱含量均在7月下旬和10月下旬出现2个明显的高峰值。长春花叶片中长春碱含量与长春质碱和文多灵含量之间均有较强的正相关,且与文多灵含量呈显著的正相关(p<0.05),长春花叶片中长春质碱含量与文多灵含量之间呈显著的正相关(p<0.05)。因此,生产实践中人工种植长春花的最佳采收期是10月末,并可通过改变环境因子进一步诱导长春花叶片中长春碱类物质的积累。  相似文献   

5.
Idioms of distress refers to the popular expression of emotional tension that arises in the relationship between sickness and kinship. By reference to case studies and discussions among the Polynesian people of Tonga, the author shows where such tension arises and how it influences the sickness process. Sickness is necessarily a collective phenomenon which can best be understood not simply as a clinical event, but as an experience that is part of the experience of family. Various ways of expressing distress as a reflexive encounter between personal and cultural meaning systems are reviewed, as are several new concepts such as doing sickness as kinship, and turning in the process of decision making in the kinship management of sickness. The explanatory models of sickness in Tonga are shown to encompass culturally sanctioned expressions of distress as part of the adaptive coping mechanisms in that society. Distress frequently emerges in somatic form, as a number of studies have shown. However, the author emphasizes the kinship meaning of sickness, kinship management and sickness therapy, the adaptive process of idiomatic expressions of distress, which are expanded here and offered as potential avenues for elaboration in other cultural milieu. Two aspects of the notion idioms of distress are noted, and the phenomenon is understood as a process which acts as a prime mover in social change.  相似文献   

6.
  • 1.1. The urate, urea and ammonia content of the whole egg of the Japanese quail was measured in late incubation in eggs subject to different rates of water loss.
  • 2.2. High rates of water loss substantially increased egg urate content, but had little or no effect on urea or ammonia content.
  • 3.3. Allopurinol, an inhibitor of urate synthesis, reduced egg urate content to low levels, but produced no effect on urea content, and a small reduction in ammonia content.
  • 4.4. The urea concentration of the embryo was lower than in allantoic fluid.
  • 5.5. It is concluded that urate production by the avian embryo is primarily concerned with the modification of allantoic fluid composition.
  相似文献   

7.
The total content of quaternary ammonium compounds (QAC) and the choline content in roots, leaves, and xylem exudates of the halophyte Suaeda altissima (L.) Pall. were determined after growing plants at various NaCl concentrations in the nutrient solution (1, 50, 100, and 250 mM). Based on the results obtained, the content of glycine betaine in organs and xylem exudates of S. altissima was estimated as the difference between the total content of QAC and the choline content. In roots choline accounted for the largest portion of QAC (from 69 to 96% at various NaCl concentrations in nutrient media), whereas in leaves it contributed only 12–23%. The contribution of choline to QAC content in the xylem exudates was 84–90%. It is concluded that choline in S. altissima is mainly synthesized in roots and is delivered with the ascending water flow to leaves where it is utilized as a substrate for glycine betaine synthesis. The content of glycine betaine in leaves increased with elevation of NaCl concentration in the nutrient solution, thus contributing appreciably to the maintenance of osmotic balance in the cytoplasm of S. altissima at high salinity.  相似文献   

8.
以同期种植的云南报春花为试验材料,利用获得的云南不同纬度、不同海拔高度,而经度差异不大的4个试验点的UV-B辐射观测资料,初步研究了低纬高原地区不同UV-B辐射强度变化对云南报春花丙二醛、可溶性蛋白质的影响。结果表明,UV-B辐射强度从2~5月呈上升趋势,辐射值最高为丽江点,5月份达12·90w·m-2,相对来说高海拔地区的紫外辐射强度较强,各试验点报春花叶片的丙二醛含量以3、4月份较高,可溶性蛋白质含量以2、4月份较高。随着UV-B辐射强度增强,报春花丙二醛含量先升高后降低,叶片丙二醛含量也较高,不同生育期丙二醛含量不同,其含量以开花期和结实期最高;而随着UV-B辐射强度的变化,各实验点报春花叶片蛋白质含量变化不一致,不同生育期可溶性蛋白质含量不同,其含量以开花期为最高。  相似文献   

9.
This article provides a review of selected presentations and events that highlighted the annual meeting of the International Society for the Advancement of Respiratory Psychophysiology (ISARP) and the 14th International Symposium on Respiratory Psychophysiology, Toronto, Ontario, Canada, October 1995. The meeting, which was scheduled as a satellite to the 35th annual meeting of the Society for Psychophysiological Research, included two workshops (Diana M. Innocenti on Identification of Individual Breathing Patterns and Introduction to the Reeducation of Dysfunctional Patterns in Hyperventilation, Asthma, and Emphysema and Richard N. Gevirtz on Respiratory and Psychophysiological Factors in the Diagnosis and Treatment of Functional Cardiac and Panic Disorders), two symposia (one on Breathing Retraining: Issues and Applications and one on Capnography and Hyperventilatory Hemodynamics), three invited addresses (Hans Folgering on Rehabilitation of Patients with Exercise Hypoxemia; David Stubbing on Assessing Impairment, Disability, and Handicap in Chronic Lung Disease; and Robert Banzett on Hypercapnia-Induced Air Hunger), three panel sessions (one on Respiratory Psychophysiology of Airway Obstruction, one on Applied Respiratory Psychophysiology, and one on Hyperventilation and Panic: Psychological Aspects), and a poster session.  相似文献   

10.
The main component of the ganglioside1 mixture from the brain of the adult amphibian Xenopus laevis accounts for 35% of the total, as lipid bound sialic acid. This ganglioside has been purified and characterized by thin layer chromatography, partial and exhaustive enzymatic hydrolysis with sialidase, TLC-overlay procedures with anti-Gg4Cer and anti-Neu5Ac6GalNAc specific monoclonal antibodies and mass spectrometry. All together the results suggest the following structure:Neu5Ac8Neu5Ac3Gal3(Neu5Ac8Neu5Ac6)GalNAc4Gal4Glc1Ceror, IV3--Neu5Ac2,III6--Neu5Ac2-Gg4Cer.  相似文献   

11.
Arsenic content was assayed in the samples of the femur head of the people living in southern and central Poland (Kraków, n=13; Silesian region, n=13; Łódź, n=12). The average age being 68.7±8.7 yr. Arsenic content in the femur head was determined applying the hydride generation atomic absorption spectrometry (HG-AAS) method after microwave mineralization. The average arsenic contents in the femur head of the residents of the Łódź, Kraków, and Silesian regions were 0.41 μg/g, 0.37 μg/g, and 0.18 μg/g, respectively. No correlation has been found between arsenic content in the femur head and the content of other metals. Neither the age nor sex of the people tested affected the arsenic content in the femur head.  相似文献   

12.
Summary Myotendinous junctions in the myotomal tail muscles of the tadpole of Rana rugosa were examined by electron microscopy. At the site of the myotendinous junction, the sarcolemma is covered on its sarcoplasmic aspect by the connecting filament layer and the attachment layer, and on the extracellular aspect by the intermediary layer and the external lamina, with associated collagen fibrils. The intermediary layer consists of filamentous structures which closely resemble microfibrils (Hanak and Böck, 1971), spine-like or thread-like profiles (Korneliussen, 1973) and intermediary layer (Nakao, 1975a, b) in the myotendinous junctions of other vertebrate skeletal muscles.Particularly interesting is the fact that all the coverings and linings of the sarcolemma, including the external lamina, are completely absent in the terminal segment of the finger-like sarcolemmal invagination characteristic of the myotendinous junction. Furthermore, special types of coupling between a sac of sarcoplasmic reticulum and a part of the sarcolemmal invagination are frequently observed. These couplings always occur along the region of the sarcolemma where the external lamina is absent. The couplings show features similar to those of the triad, such as SR feet , scalloped SR membranes and granular content of the SR sac, suggesting that they are analogous and functionally similar to the triad and other equivalent structures.  相似文献   

13.
The taxonomic significance of the trunk limbs of the chydoridae (Cladocera)   总被引:1,自引:1,他引:0  
N. N. Smirnov 《Hydrobiologia》1966,27(3-4):337-343
Summary The differences in the structure of the trunk limbs allow to outline three sections of Chydoridae (see table I and fig. 1), coinciding with the sections distinguished according to the structure of the head pores.
Chydoridae (Cladocera)
Chydoridae (. ), , .
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14.
Hamase K  Homma H  Takigawa Y  Imai K 《Amino acids》1999,17(3):277-283
Summary In a previous report (Hamase, K. et al., Biochim Biophys Acta 1134: 214–222 (1997)), we showed that the rat pineal gland contains D-leucine (D-Leu) as well as D-aspartic acid (D-Asp). In this communication we report alterations in the content of these D-amino acids during anesthesia. The D-Asp content was significantly increased from 2.8 to 5.0, 4.8 and 5.8 nmol/pineal gland by administration of ether, urethane and pentobarbital, respectively. In contrast, the D-Leu content was decreased by administration of urethane or pentobarbital. The D-Leu content decreased from 4.2 to 2.2 pmol/pineal gland 4 hours after administration of urethane, although the content remained unchanged until 1.5 hours after administration. The content of the L-enantiomers of these amino acids were not affected by anesthesia. The urethane-induced decrease in D-leucine content was almost completely suppressed by a-agonist, (-)-isoproterenol, whereas the agonist itself had no effect.  相似文献   

15.
Summary This paper deals with the ultrastructure of two types of intranuclear inclusions, nuclear bodies and membranous lamellar bodies, present in hypothalamic pericytes of intact adult rats. The nuclear bodies exhibited simple and granular forms, whereas the membranous lamellar bodies were entirely made up of myelin-like membrane whorls.The occurrence of these bodies in nuclei of pericytes has never been previously reported. The origin and functional meaning of such structures is discussed in the light of recent ultrastructural and biochemical studies on nuclear inclusions.  相似文献   

16.
T. M. Butt  A. Beckett 《Protoplasma》1984,120(1-2):61-71
Summary A detailed account of the ultrastructure and behaviour of the spindle pole body (SPB) of the entomophthoraceous fungusErynia neoaphidis is presented for the first time.The SPB consists of extranuclear (ENC) and intranuclear (INC) components. The ENC is a saucepan-shaped structure which lies in a pocket of the nuclear envelope. It is composed of a forked, fibrillar handle and a shallow, cylindrical pan. The pan has a wall of two layers, both of which are thickened with a regular periodicity so that they appear to be beaded. It is postulated that the pan is formed from rough endoplasmic reticulum and that it synthesizes the amorphous, electron-dense material coating the ENC.The INC is a saucer-shaped, electron-dense plaque in which the ends of the spindle microtubules terminate. During metaphase, a clear zone separates the INC from the nuclear envelope and persists until telophase. The roles of the amorphous, electron-dense material and the clear zone as well as the method of SPB replication are discussed.  相似文献   

17.
Summary Solute osmotic potentials (x) in the vessels of hydroponically grown maize roots were measured to assess the osmotic-xylem-sap mechanism for generating root pressure (indicated by guttation). Solutes in vessels were measured in situ by X-ray microanalysis of plants frozen intact while guttating. Osmotic potentials outside the roots (o) were changed by adding polyethylene glycol to the nutrient solution. Guttation rate fell when o was decreased, but recovered towards the control value during 3–5 days when o was greater than or equal to –0.3 MPa, but not when o was equal to –0.4 MPa. In roots stressed to o = –0.3 MPa, x, was always more positive than o, and x changed only slightly (ca. 0.05 MPa). Thus the adjustment in the roots which increased root pressure cannot be ascribed to x, contradicting the osmotic-xylem-sap mechanism. An alternative driving force was sought in the osmotic potentials of the vacuoles of the living cells (v), which were analysed by microanalysis and estimated by plasmolysis. v showed larger responses to osmotic stress (0.1 MPa). Some plants were pretreated with abundant KNO3 in the nutrient solution. These plants showed very large adjustments in v (0.4 MPa) but little change in x (0.08 MPa). They guttated by 4 h after o was lowered to –0.4 MPa. It is argued that turgor pressure of the living cells is a likely alternative source of root pressure. Published evidence for high solute concentrations in the xylem sap is critically assessed.Abbreviations o external water potential - x osmotic potential of xylem sap - v osmotic potential of vacuolar sap - EDX energy dispersive X-ray microanalysis - CSEM cryo-scanning electron microscope - LN2 liquid nitrogen - PEG polyethylene glycol  相似文献   

18.
The regional difference in the carbohydrate components of the ductus epididymis epithelium of a lizard was delineated by means of 13 lectins. Basal cells expressed only N-acetylglucosamine (GlcNAc). Throughout the ductus, the secretory cells showed oligosaccharides with terminal N-acetylneuraminic acid (Neu5Ac)(2,6)galactose (Gal)/N-acetylgalactosamine (GalNAc) and internal mannose (Man) and/or glucose (Glc) in the whole cytoplasm, oligosaccharides terminating in Neu5Ac(2,6)Gal(1,3)GalNAc, Neu5Ac(2,6)Gal (1,4)GlcNAc, GalNAc, GlcNAc, and fucose (Fuc) in the supra-nuclear zone, and also glycans terminating in Neu5Ac(2,3)Gal (1,4)GlcNAc, Neu5Ac(2,6)Gal(1,3)GalNAc, Gal (1,4)GlcNAc on the luminal surface. In the caput and corpus regions, the supra-nuclear cytoplasm was characterized by terminal Gal(1,4)GlcNAc and GalNAc, the luminal surface by GalNAc and Gal. The Golgi zone, showing oligosaccharides with terminal Neu5Ac(2,3)Gal (1,4)GlcNAc, Neu5Ac(2,6)Gal (1,3)GalNAc, Neu5Ac(2,6)Gal (1,4)GlcNAc, and internal GlcNAc, expressed terminal Gal (1,4)GlcNAc and GalNAc in the caput, and terminal GalNAc in the corpus. The granules showed all the investigated carbohydrates in their peripheral zone except terminal GalNAc and Fuc, whereas internal Man/Glc and terminal Gal were expressed in the central core, and Fuc throughout the ductus, terminal GlcNAc in the caput and corpus, and terminal GalNAc only in the corpus.  相似文献   

19.
All models of self-motion from optical flow assume the instantaneous velocity field as input. We tested this assumption for human observers using random-dot displays that simulated translational and circular paths of movement by manipulating the lifetime and displacement of individual dots. For translational movement, observers were equally accurate in judging direction of heading from a velocity field with a two-frame dot life and a direction field in which the magnitudes of displacement were randomized while the radial pattern of directions was preserved, but at chance with a speed field in which the directions were randomized, preserving only magnitude. Accuracy declined with increasing noise in vector directions, but remained below 2.6° with a 90° noise envelope. Thus, the visual system uses the radial morphology of vector directions to determine translational heading and can tolerate large amounts of noise in this pattern. For circular movement, observers were equally accurate with a 2-frame velocity field, 3-frame acceleration displays, and 2-frame and 3-frame direction fields, consistent with the use of the pattern of vector directions to locate the center of rotation. The results indicate that successive independent velocity fields are sufficient for perception of translational and circular heading.  相似文献   

20.
The structures of the N-linked sugar chains in the PAS-6 glycoprotein (PAS-6) from the bovine milk fat globule membrane were determined. The sugar chains were liberated from PAS-6 by hydrazinolysis, and the pyridylaminated sugar chains were separated into a neutral (6N) and two acidic chains (6M and 6D), the acidic sugar chains then being converted to neutral sugar chains (6MN and 6DN). 6N was separated into two neutral fractions (6N13 and 6N5.5), while 6MN and 6DN each gave a single fraction (6MN13 and 6DN13). The structure of 6N5.5, which was the major sugar chain in PAS-6, is proposed to be Man16 (Man13) Man14GlcNAc14GlcNAc-PA; 6N13, 6MN13 and 6DN13 are proposed to be Gal13Gal14GlcNAc12Man16 (Gal13Gal14GlcNAc12Man13) Man14GlcNAc14 (Fuc16)GlcNAc-PA;6M and 6D had 1 or 2 additional NeuAc residues at the non-reducing ends of 6MN13 and 6DN13, respectively. © 1998 Rapid Science Ltd  相似文献   

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