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1.
Summary A small population of T cells does not express the conventional T cell receptor characterized by the and polypeptide chains (TCR) but instead, two polypeptides termed and (TCR). This alternative receptor is able to recognize antigen. It appears early in T cell ontogeny, but its role in the thymus prior to the availability of TCR remains unclear. In selected sites such as skin or gut TCR predominates in mice which might suggest a role of T cells in the first line of defense against infection, T cells secrete lymphokines and display cytotoxic activity. However, their activation requirements may differ from what is known for T cells since MHC-nonrestricted and also CD4 and CD8 negative T cells have been described. Preferential activation by mycobacterial antigens possibly indicates a special repertoire of the T cells. In various diseases slightly increased numbers of T cells were found, but these preliminary studies have not yet provided evidence for a major pathogenetic role of T cells.List of abbreviations C constant region (immunoglobulin or TCR gene segment) - CD4 cluster of differentiation 4 (mainly on helper cells) - CD8 cluster of differentiation 8 (mainly on cytotoxic cells) - D diversity region (immunoglobulin or TCR gene segment) - DNA desoxyribonucleic acid - IL2 interleukin 2 - J joining region (immunoglobulin or TCR gene segment) - kD kiloDalton - MHC major histocompatibility complex - NK natural killer (cells) - RA rheumatoid arthritis - TCR T cell receptor - V variable region (immunoglobulin or TCR gene segment)  相似文献   

2.
Zusammenfassung Auf Grund ihres immunbiologischen Verhaltens gehören die Leptospirenstämme Sari, Ghidorsi und Szwajizak zu demselben serologischen Leptospirentyp, für den der Name Leptospira Mini vorgeschlagen wird.Der Stamm Sari wurde 1942 vonMino sowieVercelli in Italien isoliert. Der Stamm Ghidorsi wurde von uns im Zuge unserer Leptospirenforschungen bei einer Reisfeldarbeiterin der Po-Ebene nachgewiesen. Der Stamm Szwajizak, der vonSmith, Brown, Tonge u. Mitarb. im Jahre 1954 beschrieben wurde, ist in Nord-Qeensland gefunden worden. Der Stamm Sari und Ghidorsi gehören dem kompletten Biotyp (AB), der Stamm Szwajizak dem inkompletten (A) an.Leptospira Mini gehört zur Serogruppe hebdomadis. Ihre Virulenz ist schwach und ihre Bedeutung als Erreger menschlicher Leptospiren-infektionen scheint gering zu sein.  相似文献   

3.
Summary Comprehensive hemagglutination inhibition (HI) and neuraminidase inhibition (NI) cross reaction tests were performed using 8 of 9 serotypes of avian paramyxoviruses (PMV). The studies were designed as full scale repeating experiments which permitted an adequate statistical treatment and elaboration of quantitative criteria of antigenic kinship. The results have shown diverse antigenic relationships between different avian paramyxovirus (PMV) serotypes which were asymmetric in some cases. The antigenic relationships found by HI test did not always parallel those found by NI tests. The antigenic inter-relationships have been displayed quantitatively in a diagram. This has given a basis for some suggestions concerning: a) the independent antigenic drift of the HA and Nase antigenic sites of hemagglutinin-neuraminidase (HN) glycoprotein of avian PMVs; b) a tentative subdivision of the whole group of avian PMVs into two subgroups: the first including PMV-2 and PMV-6 serotypes and the second including PMV-1, PMV-3, PMV-4, PMV-7, PMV-8 and PMV-9 serotypes; c) the conception that genomic material coding for the HN glycoprotein consists of a common-to-all-the-PMVs portion and a serotype-specific portion, on one hand, and of a conserved portion and a variable portion, on the other; the ratios between the portions have been shown to be different for, at least, certain PMV serotypes; d) the evolutionary pathways of the avain PMV HN antigenic drift.With 2 Figures  相似文献   

4.
Ohne ZusammenfassungMit 4 Textabbildungen. Albrecht Bethe zum 80. Geburtstag in treuer Verehrung.Ermöglicht wurde diese Untersuchung durch Unterstützung des Baruch Center of Physical Medicine and Rehabilitation und durch Kontrakt zwischen der Office of Naval Research und dem Medical College of Virginia.  相似文献   

5.
Summary For the budding yeast Saccharomyces cerevisiae the mitotic cell cycle is coordinated with cell mass at the regulatory step start. The threshold amount of cell mass (reflected as a critical size) necessary for start is proportional to nutrient quality. This relationship leads to a transient accumulation of cells at start, termed nutrient modulation, upon enrichment of nutrient conditions. Nutrient enrichment abruptly increases the critical size needed for start, causing the smaller cells, produced in the previous cell cycle, to be delayed at start while growing larger. Here we show that, in S. cerevisiae, a second cell-cycle step, at mitosis, also exhibits nutrient modulation, and is, therefore, another point of cell-cycle regulation. At both mitosis and start, nutrient modulation was found through mutation to be regulated by the activity of the cyclin-related WHI1 (CLN3) gene product.  相似文献   

6.
Summary In rabbit kidney cells infected with strains of Herpes simplex virus producing either cell-rounding or polycaryocytosis, Vinblastine induced paracrystals. This could be shown by phase-contrast- and electron-microscopy. Infections were done under one-step-growth conditions or at low MOI.90 per cent noninfected cells contained stress fibers as detected by Servablue R250-staining. Shortly after recruitment into polycaryocytes, stress fibers of normal length appearing in criss-cross arrangement can be seen in the periphery of these cells. Later they polymerize to very long fibers and finally they are partially destroyed. The time of destruction depends on the MOI employed. By using Actinomycin D and/or Cycloheximide as blocking agents, it could be shown that polymerization of microfilaments correlates in time with giant cell formation. In view of the fact that the virus synthesis is accompanied in parallel by a special rearrangement of microfilaments as well as polycaryocytosis, both these processes have to be considered as caused by early (and late?) protein-synthesis (-/-proteins) but not as induced by very-early proteins (-proteins).With 10 FiguresIn part presented at the Meeting of the Section Virologie of the Deutsche Gesellschaft für Hygiene und Mikrobiologie, 1980, Tübingen.  相似文献   

7.
Sections of bovine ovaries fixed in Bouin's fluid or methanol-acetic acid and embedded in paraffin were incubated with chicken polyclonal antibodies to HPLC-purified zona glycoproteins ZP3 and ZP3. Oocytes of primordial follicles as well as of primary follicles showed weak labelling with anti-ZP3 and anti-ZP3. No immunostaining could be observed in the follicle cells. The ZP of primary follicles displayed distinct immunoreactivity for both ZP3 and ZP3. In secondary follicles, distinct labelling with anti-ZP3 and weak labelling with anti-ZP3 could be seen in the oocyte. The ZP showed immunoreactivity with antibodies to ZP3 and ZP3. Both antibodies labelled single follicle cells. In tertiary follicles, the oocytes were weakly labelled with anti-ZP3 and anti-ZP3. Some granulosa cells showed staining for ZP3 and ZP3. The ZP displayed strong immunoreactivity for ZP3 and ZP3. Cells of the corona radiata were strongly immunopositive for ZP3 and ZP3. Similar histotopography of immunoreactive cells could be seen in preovulatory follicles. The characteristic pattern observed for the distribution of ZP3 and ZP3 strongly suggests that in the porcine ovary both the oocyte and the follicle cells contribute to the synthesis of the ZP, perhaps in sequence.  相似文献   

8.
Summary Studies have been made of the heterogeneity of infectivity and CFA in Teschen virus (Talfan strain) suspensions. Most of the infectivity was contained in two components of densities 1.46 gm./ml. and 1.35 gm./ml. The physical, chemical and immunological properties of these components have been compared. It was possible, however, to convert a large proportion of 1.46 component to 1.35 component by treating the 1.46 component with sodium dodecyl sulphate. This would indicate that the 1.46 component was a complex formed between the infective particles and cellular debris.Further studies on the growth characteristics and electron microscopy of the virus have been made.  相似文献   

9.
Zusammenfassung Untersuchungen über den Einfluß von 9-Fluorcortisol auf die Nebennierenrindenfunktion ergaben — in Verbindung mit in der Literatur mitgeteilten Werten — eine dosisabhängige Einschränkung der Ausscheidung von Nebennierenrindenhormonen. Die Ansprechbarkeit der Nebennierenrinde auf exogenes ACTH bleibt erhalten. Es ist daher eine Hemmung der hypophysären ACTH-Sekretion anzunehmen, die durch die Struktur des synthetischen Steroids erklärbar ist. — In geringer Dosierung, wie sie als Erhaltungsdosis bei Langzeittherapie verabfolgt wird, verursacht 9-Fluorcortisol keine wesentliche Einschränkung der Hormonausscheidung.
Effect of 9-fluorocortisol on adrenocortical function
Summary Investigation of adrenal cortical function during administration of 9-fluorcortisol revealed—in connection with results obtained from the literature—a dose-related inhibition of the secretion of adrenocortical hormones. Adrenal cortical response to exogenous ACTH remains unaffected. An inhibition of hypophyseal ACTH-secretion is therefore assumed, caused by the structure of the synthetic steroid. At low dosage, as applied in long-term treatment, no significant alteration of steroid excretion patterns was observed.


Astonin-H, Hersteller: Fa. E. Merck A.G., Darmstadt.

In der Arbeit werden folgende Abkürzungen verwendet: 17-KS=17-Ketosteroide; 17-OH-CS=17-Hydroxycorticosteroide; F=Cortisol=Pregn-4-en-11,17,21-triol-3,20-dion; E=Cortison=Pregn-4-en-17,21-diol-3,11,20-trion; THF=Tetrahydrocortisol=5-Pregnan-3,11,17,21-tetrol-20-on; allo-THF=allo-Tetrahydrocortisol=5-Pregnan-3,11,17,21-tetrol-20-on; THE=Tetrahydrocortison=5-Pregnan-3,17,21-triol-11,20-dion; Andro=Androsteron=5-Androstan-3-ol-17-on; Ätio=Ätiocholanolon=5-Androstan-3-ol-17-on; DHA=Dehydroepiandrosteron=Androst-5-en-3-ol-17-on.

Herrn Prof. Dr. med. H. Franke zum 60. Geburtstag gewidmet.  相似文献   

10.
A possible mechanism is proposed for the enhancement/weakening of those cortical signals in the cortex-basal ganglia-thalamus-cortex neural network which induce/do not induce opening of NMDA channels in the spiny neurons of the striatum and which can be regarded as strong/weak in terms of this measure. The mechanism is based on the modulatory influences of dopamine on changes in the efficiency of corticostriatal inputs. In the absence of dopamine, relative increases in the intensity of strong (weak) cortical signals can lead to the induction of long-term potentiation (depression) of corticostriatal synapses. In this case, because of the differently directed influences on thalamic cells of signals passing via strionigral and striopallidal cells, strong signals at the output of the thalamus are weakened, while weak signals are strengthened. Activation of dopamine D1 (D2) receptors on strionigral (striopallidal) neurons may facilitate increases in the extent of long-term potentiation/depression (decreases in the extent of long-term potentiation/depression or induction of long-term potentiation/depression). The consequence of this is that strong signals at the output of the thalamus can be strengthened synergistically, while weak signals cab be weakened synergistically. Background cortical signals evoking tonic release of dopamine in the striatum can decrease strengthening because of weakening of the modulatory influence of dopamine on the modification of corticostriatal synapses.  相似文献   

11.
Pretreatment of pancreatic cells with pertussis toxin resulted in a 30% increase in peak whole-cell Ca2+ currents recorded in the absence of exogenous intracellular guanine nucleotides. Intracellular application of 90 M GTP[S], by liberation from a caged precursor, resulted in 40% reduction of the peak Ca2+ current irrespective of whether the current was carried by Ca2+ or Ba2+. Effects on the delayed outward K+ current were small and restricted to a transient Ca2+-dependent K+ current component. Inhibition by GTP[S] of the Ca2+ current was not mimicked by standard GTP and could not be prevented either by pretreatment with pertussis toxin or by inclusion of GDP[S] or cyclic AMP in the intracellular medium. The inhibitory effect of GTP[S] could be counteracted by a prepulse to a large depolarizing voltage. A similar effect of a depolarizing prepulse was observed in control cells with no exogenous guanine nucleotides. These observations indicate that inhibition of cell Ca2+ current by G protein activation results from direct interaction with the channel and does not involve second-messenger systems. Our findings also suggest that the cell Ca2+ current is subject to resting inhibition by G proteins.  相似文献   

12.
    
Summary The nuclear inclusions characteristic of the virosis of dense nuclei of the Lepidoptera have been identified, by electron microscopic cytological studies, as aggregations of elements corresponding to the paraspherical virus isolated from infected cells.  相似文献   

13.
Summary Damage to the anterior limbic and motor regions of the brain cortex results in two types of distribution of degenerated fibers over the brain cortex in dogs. The first lateral type is characterized by a predominant fragmentation of a large number of thick horizontal or diagonal fibers of the lower cortical layers on the lateral surface; the second type, known as medial, by the fragmentation of single slender radial fibers and horizontal fibers of the first cortical layer on the medial surface.The lateral-type degenerated fibers are distributed over the cortex of the sigmoid, presplenial, suprasplenial and ectolateral convolutions (motor, parietal and occipital fields). They are most numerous in the motor (4) and optic (19, 18) areas. The medial-type degeneration is characteristic of the cingulum (gyrus cinguli) (limbic fields).An injury to the anterior and posterior portions of the sigmoid convolution causes a less extensive lateral-type degeneration than an injury to the genual convolution.Presented by Academician V. N. Chernigovskii Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 59, No. 3, pp. 18–22, March, 1965  相似文献   

14.
Zusammenfassung Die Abstammung der-Globuline im Liquor wurde bei 20 Fällen mit den verschiedensten neurologischen Erkrankungen untersucht. — Die spezifische Aktivität der-Globuline war bei normalen und pathologischen Liquors ausnahmslos niedriger als im Serum. Es treten demnach nur einzelne Serum--Globuline in den Liquor über, ein verschieden großer Anteil der Liquor--Globuline wird im Liquorraum gebildet. Die-Fraktion im Liquor besitzt einen Serumanteil, von dem die liquoreigenen oder auch cerebrogenen-Globuline unterschieden werden können. Beziehungen zwischen der Höhe des liquoreigenen-Globulinanteils zu einzelnen Krankheitsgruppen waren nicht herzustellen. Es ließ sich aber zeigen, daß eine Erhöhung des elektrophoretisch ermittelten relativen-Globulingehaltes im Liquor bei pathologischen Fällen nicht — wie bisher angenommen wurde — mit einer Zunahme des cerebrogenen Eiweißes einherzugehen braucht. — Die Bedeutung des liquoreigenen-Globulins ist noch unbekannt, auch ist es nicht möglich zu entscheiden, welche einzelnen Proteine innerhalb der-Fraktion im Liquorraum entstanden sind oder aus dem Serum stammen.Mit Unterstützung der Deutschen Forschungsgemeinschaft.  相似文献   

15.
Summary A new method for the separation of isoenzymes of-glutamyl-transpeptidase is described, using electrophoresis on acetate cellulose gel and a developing solution composed by-glutamyl-naphthylamide, and a colored diazonium compound.The method permits the separation of up to four different isoenzymes, which we called-GT1,-GT2,-GT3,-GT4, the first two showing an electrophoretic migration similar to that of 1- and 2-globulins and the other two to that of-globulins.The present technique has proved its usefulness in detecting isoenzymes in serum with values of total-glutamyl-transpeptidase higher than 80 U/L.The application of this method in 52 patients with different types of biliary obstruction and hepatocellular damage has shown that it provides new possibilities in differential diagnosis.  相似文献   

16.
Zusammenfassung Die Ergebnisse optischer Drehfähigkeitsmessungen an H- und L-Polypeptidketten normaler und Myelomproteine vom G-Typ werden mitgeteilt und mit den optischen Konstanten kompletter G-Proteine verglichen. Durch Kreuzungen zwischen unspezifischen und spezifischen Polypeptidketten werden die Bedingungen einer spezifischen Rekombination geprüft. Sie sind insbesonders dann gegeben, wenn autologe, d.h. vom gleichen Myelomprotein stammende Polypeptidketten gemischt werden. Die Befunde werden in ihrer Beziehung zum Problem der Antikörperspezifität diskutiert.
Summary The results of measurements of the optical rotatory dispersion on H- and L-polypeptide chains of normal and myeloma proteins are reported Comparisons of the optical parameters with those of the whole G-proteins were performed. By mixing of normal or unspecific and myeloma or specific polypeptide chains the conditions of specific recombination were examined. Specific recombination occurs especially when autologous chains, that means polypeptide chains of an individual myeloma protein, are mixed. The implications of this finding are discussed with respect of the problem of antibody specifity.


Herrn Prof. Dr.H. E. Bock zum 65. Geburtstag.  相似文献   

17.
Summary Electron microscope observations of the excretory cell of the infective larva reveal that it contains a large nucleus surrounded by cytoplasm containing numerous organelles, multi-granular bodies, vesicles and granules typical of glandular cells. The proximal region of the excretory duct bears a number of scattered microvilli, on its adluminal surface, and the distal region is lined with a thin multilayered cuticle.In the liver stage larva 2 days after infection, 2 lateral excretory columns are present. These arise from the excretory cell body and extend posteriorly for about half the length of the intestine. Each column contains a narrow longitudinal canal surrounded by cytoplasm rich in mitochondria, granular endoplasmic reticulum, free ribosomes and large vacuoles. Evidence was obtained of the passage of substances through the wall of the canal but their chemical nature was not determined.Further extension of the lateral columns is seen in the 8-day, lung-stage larva, the columns now extending for more than two-thirds the length of the intestine. Their diameter is also increased but their internal structure is essentially similar to that of the 2-day liver-stage larva.The excretory duct which arises immediately anterior to the nucleus has a structure similar to that of the lateral columns for the first half of its length, the microvilli described in the infective larva being absent at this stage. The distal half of the duct is lined with cuticle.  相似文献   

18.
Zusammenfassung Der Gehalt an Immunglobulinen G, A und M im Serum schwangerer, gesunder Frauen wurde in Abhängigkeit vom Alter der Gravidität geprüft und verglichen mit den Werten aus Seren eines Kollektivs weiblicher Blutspender gleicher Altersstufe. Es wurde festgestellt, daß der Serumspiegel an G stark absinkt, der Gehalt an A eine sinkende Tendenz zeigt und der M-Spiegel unbeeinflußt bleibt.
Summary Serum of pregnant healthy women was investigated for its percentage of Ig G, Ig A and Ig M dependent from the stage of pregnancy. These measurements were compared with results from a group of female blood-donors of the same age. It was concluded, that the serumcontent of G decreases very distinctly, the Ig A percentage is somewhat diminished whereas the M content shows no differences between the two groups.
  相似文献   

19.
Summary The terms reticulosis and reticulum cell sarcoma (= malignant lymphoma, histiocytic type) are discussed regarding the modern concept of the monocyte macrophage system which today has replaced the ancient theory of the reticuloendothelial system. The monocyte macrophage system is not independent, but closely related to the myeloid system. Thus, a third blood forming system as was believed in the case of RES does not exist. Phagocytic reticulum cells of the various hematopoietic organs are highly activated monocyte-derived macrophages. All those conditions formerly termed reticuloses have been found to belong either to the myeloid or to the lymphatic system. Considering the reticulum cell sarcomas or malignant histiocytic lymphomas, most of them seem to be of lymphatic rather than of macrophage origin, representing highgrade malignant lymphomas, possibly immunoblastic sarcomas. No relationship between these tumours and the monocyte macrophage system has been established, so far. Therefore, the terms reticulosis and reticulum cell sarcoma should be no longer used in order to avoid confusion, in order to stimulate sufficient diagnostic efforts which will really clarify such cases, and in order to give full credit to modern results of hematopathology.  相似文献   

20.
Summary 1.Responses were recorded from 160 ascending tract cells in segments L4 to L6 of the spinal cord in chloralose anaesthetized, spinalized cats. The tract cells were identified by antidromic activation following stimulation of pathways in the lateral and ventral funiculi at the level of the spinal cord transection at the thoracolumbar junction. Axonal conduction velocities ranged from 9 to 114 m/s. 2. A sample of 152 of the neurones examined could be subdivided according to the distribution of their receptive fields into 49 cells activated just from receptors located in skin (s cells), 17 neurones excited by receptors in deep tissues (d cells), 15 units with a convergent input from receptors in skin and deep tissues (sd cells), and 25 neurones with a convergent input from the knee joint and either skin (sj cells), deep tissues (dj cells) or both (sdj cells). No receptive fields could be demonstrated for the remaining 46 neurones. 3. S and sj cells were found almost exclusively in the dorsal horn, whereas many d, sd, sdj and dj units were in the ventral horn. Almost all of the cells that lacked receptive fields were in the ventral horn or intermediate grey. 4. Ninety-one of 158 cells (56%) demonstrated no background activity. Of these, 43 cells (27%) lacked receptive fields. Many of the silent neurones were in the ventral horn, but some were in the dorsal horn. Of 25 cells having knee joint input, 18 (72%) had background activity. 5. All of the neurones that had a receptive field in the knee joint also had a convergent input from receptors in other tissues. In 3 cases, there was a receptive field in the skin over the foot (sj cells). For 16 cells, receptive fields included not only the knee joint but also skin and deep tissue (sdj cells). Usually, the cutaneous receptive field was near the knee joint, but sometimes it was remote, such as on the foot. The deep receptive fields were chiefly in the muscles of the thigh and/or leg. For 6 dj cells, the receptive fields included not only the knee joint but also deep fields like those of sdj cells. 6. Cutaneous receptive fields were classified as low threshold (cells excited best by innocuous intensities of mechanical stimulation), wide dynamic range (cells activated by weak mechanical stimuli, but the best responses were to noxious stimuli) or high threshold (innocuous stimuli had little effect, but noxious mechanical stimuli produced a vigorous discharge). Similarly, stimulation of the knee joint with weak mechanical stimuli could excite some neurones, while others could be activated by weak or strong articular stimuli but were excited best by noxious stimuli, and still other neurones were activated by knee joint stimuli only if the intensity was noxious. 7. In several instances, contralateral receptive fields were noted. These were generally in deep tissue or in the knee joint. 8. It was concluded that many of the responses to articular stimulation of the spinal cord ascending tract cells examined in this study could have been mediated by the fine afferent fibres that supply the knee joint. Although further work will be required to determine which particular ascending tracts transmit nociceptive information concerning the knee joint, it can be proposed that many of the responses demonstrated here were likely to play a role in either joint pain of in triggering responses associated with joint pain.  相似文献   

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