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1.
Specific coagulation factor adsorption to insoluble heparin   总被引:5,自引:0,他引:5  
An insoluble derivative of heparin has been prepared by coupling to agarose beads, and its adsorption of certain blood clotting factors has been investigated. Factors IX* XI, and heparin cofactor (He-Co)** are selectively adsorbed, and can be recovered by elution of the heparin-agarose (H-Ag) with an NaCl gradient. Fibrinogen (FI) adsorption is negligible. The affinity for F IX appears to be lower than for F XI and He-Co. Thrombin, F XI, and He-Co seem to be equally tightly bound to the insoluble H.  相似文献   

2.
Lutalyse*, a commercial preparation of prostaglandin F2a was injected intramuscularly into nulliparous heifers of the German Brown, Holstein—Friesian and White Fulani cattle. Two injections, 25mg/animal each time, were given at intervals of 12 days. All the heifers were inseminated 80h after the second injection. Heifers that were cycling responded well to the treatment and had a higher conception rate than the controls.  相似文献   

3.
Over the past decade, there has been a growing interest in investigating whether disordered proteins can be targeted for clinical purposes using small molecules [1], [2], [3], [4], [5], [6], [7], [8]. While small-molecule binding to disordered proteins can be seen as unorthodox, examples of this phenomenon have been reported. In order to rationalize these observations, a variety of models are emerging, sometimes in apparent contradiction. Here, we offer a structural ensemble modulation” view as an attempt to clarify the language, organize concepts, and facilitate the comparison of different studies. In doing so, we hope to promote the understanding of the general principles underlying this phenomenon toward the development of novel therapeutic compounds targeting disordered proteins, which are prevalent in a wide range of human diseases [1], [2], [3], [4], [5], [6], [7], [8].  相似文献   

4.
Bernard Courtinat 《Geobios》1980,13(2):209-229
Palynological inventory of Saint-Fromont pit 0815 (Manche, France) related to Hettangian seems to show the conspecificity of Classopollis chateaunoviReyre, 1970, Classopollis kieseriReyre, 1970 and Classopollis harisiiMuir & Van Konijnenburg-Van Cittert, 1970. SEM pictures exibit some sculptural elements interpreted as structural attachments of grains in tetrad and compared to those of genus DicheiropollisTrevisan, 1971.  相似文献   

5.
Disparate occurrence of breast cancer remains an intriguing question since only a subset of women with known risk factors develop cancer. Recent studies suggest an active role of local and distant microbiota in breast cancer initiation, progression, and overall prognosis. A dysbiotic microbiota predisposes the body to develop cancer by inducing genetic instability, initiating DNA damage and proliferation of the damaged progeny, eliciting favorable immune response, metabolic dysregulation and altered response to therapy. In this review, we present our analyses of the existing datasets and discuss the local dysbiosis observed in breast cancer patients and different aspects of breast carcinogenesis that can be potentially influenced by local breast microbiota. Striking differences between microbial community compositions in breast of cancer patients compared to healthy individuals were noted. Differences in microbiome were also apparent between benign and malignant disease and between nipple aspirate fluid of healthy individuals and breast survivors. We also discuss the identification of distinct bacterial, fungal, viral as well as parasite signatures for breast cancer. These microbes are capable of producing numerous secondary metabolites that can act as signaling mediators effecting breast cancer progression. We review how microbes potentially alter response to therapy affecting drug metabolism, pharmacokinetics, anti-tumor effects and toxicity. In conclusion, breast harbors a community of microbes that can communicate with the host cells inducing downstream signaling pathways and modulating various aspects of breast cancer growth and metastatic progression and an improved understanding of microbial dysbiosis can potentially reduce breast cancer risk and improve outcomes of breast cancer patients.The human microbiome, now referred to as, the “forgotten organ” contains a metagenome that is 100-fold more diverse compared to the human genome, thereby, is critically associated with human health [1,2]. With the revelations of the human microbiome project and advent of deep sequencing techniques, a plethora of information has been acquired in recent years. Body sites like stomach, bladder and lungs, once thought to be sterile, are now known to harbor millions of indigenous microbial species. Approximately 80% of the healthy microbiome consists of Firmicutes and Bacteroidetes accompanied by Verrucomicrobia, Actinobacteria, Proteobacteria, Tenericutes and Cyanobacteria [[2], [3], [4], [5], [6], [7]]. The role of microbiome in diabetes, obesity and even neurodegenerative diseases was greatly appreciated in the last decade [1,[7], [8], [9], [10], [11], [12], [13], [14]] and now it has been established that microbiome significantly contributes to many organ specific cancers [1,15,16].  相似文献   

6.
During recent years, numerous attempts have been made to correlate both quantitative (Davies &; Taylor, 1959; Engen, 1962; Beck, 1964; Engen, Cain &; Rovee, 1968; Cain, 1969; Dravnieks &; Laffoit, 1970; Laffort, 1969a,b) and qualitative (Davies, 1965; Amoore &; Venstrom, 1965; Döving, 1966a,b; Wright &; Michels, 1964; Leveteau &; MacLeod, 1969) odorous properties of single compounds to their molecular properties. These attempts have been only partially successful.In the present paper we will try to explain the several odorous properties of single compounds on the basis of the non-specific properties of odorants involved in solubility.This model is a first approach, and although it gives statistically highly significant relations, it is not as accurate as those advanced with respect to the physical and sensory dimensions of stimuli in the fields of vision and audition.We will first give the present definitions of the most suitable physicochemical parameters, and then advance quantitative and qualitative models for single compounds. Quantitative odorous properties are: odour threshold, rate of change of odour intensity with odorant concentration in the suprathreshold region, and the somewhat controversial upper odour intensity. Qualitative properties refer to odour character.  相似文献   

7.
Peter M. Galton 《Geobios》1985,18(5):671-676
The femur of the anchisaurid (= plateosaurid) prosauropoddinosaur Euskelosaurus browniiHuxley, 1866 from the lower Elliot Formation (Upper Triassic) of South Africa is sigmoidal in posterior view with the fourth trochanter well removed from the medial edge. The sympatric Melanorosaurus readiHaughton, 1924 is not a junior synonym of Euskelosaurus brownii because the femur is straight in posterior view with the fourth trochanter close to the medial edge. In addition to Melanorosaurus, the Melanorosauridae Huene, 1929 includes Camelotia borealis nov. gen. and nov. sp. from the Upper Triassic of England, Riojasaurus incertusBonaparte, 1969 from the Upper Triassic of Argentina, and possibly some of the posteranial material referred to the? rauisuchian the codontian Sinosaurus triassicusYoung, 1948 from the Lower Jurassic of China.  相似文献   

8.
Biological temperature-dependent rate models based on Arrhenius' and Eyring's equations have been formulated by Johnson & Lewin (1946), Hultin (1955), and Sharpe & DeMichele (1977). The original formulation of Sharpe and DeMichele is poorly suited for non-linear regression. Very high correlations of parameter estimators occassionally make regression with their equation impossible using Marquardt's algorithm (1963).This analysis describes a new formulation of Sharpe and DeMichele's model that greatly alleviates the non-linear regression problem. It is partly based on Hultin's formulation (1955). Biological and graphical interpretation of the model parameters is discussed. Regression suitability is illustrated with a typical data set. Similar modifications to the equations of Hultin (1955) and Johnson & Lewin (1946) are described.  相似文献   

9.
10.
The revision of Agrilus (Coleoptera, Buprestidae) pests of citrus trees from A. angulatus species–group comprising six species: A. angulatus (Fabricius, 1798); A. connatus sp. nov.; A. livensKerremans, 1892a, Kerremans, 1892b; A. mediocrisKerremans, 1900; A. nubilusKerremans, 1892a, Kerremans, 1892b and A. olivaceidorsisObenberger, 1917 from South and Southeast Asia is provided. The study is based on examination of all relevant types and 2498 additional specimens. The key to species is given and complemented with illustrations of morphology, habitus, genitalia, size variability, color variability, type specimens and distribution. Comprehensive commented literature references, data on type specimens, faunal records, revised and updated distribution and host plant data are cited for each species. The new species A. connatus sp. nov. from Laos and Thailand is described. The following taxonomic and nomenclatural acts are proposed: the name grisatorKerremans, 1893syn. nov. (Agrilus) is a junior subjective synonym of the name nubilusKerremans, 1892a, Kerremans, 1892b (Agrilus); the name macellusBourgoin, 1922syn. nov. (Agrilus) is a junior subjective synonym of the name olivaceidorsisObenberger, 1917 (Agrilus); the lectotype of Buprestis angulataFabricius, 1798 (now in Agrilus) is designated.www.zoobank.org/urn:lsid:zoobank.org:pub:BAE5BD51-2811-44CE-8BC1-AEEC76075667  相似文献   

11.
12.
13.
The Island Model introduced by Sewall Wright (1951) has proven to be a useful construction for studying the interaction of genetic drift, population subdivision, and mutation. Interest in the model has recently increased because of its relevance to certain questions involving the rate of differentiation of sub-populations under the neutral allele hypothesis (e.g., Smith, 1970; Latter, 1973). It is perhaps the only realistic population structure in which the test for neutrality proposed by Lewontin and Krakauer (1973) is valid (Lewontin and Krakauer, 1975). If data from natural populations is to be compared to the predictions of the Island Model, it is desirable to have an alternative model with the same migration pattern but with natural selection operating. In this paper one such model will be introduced where the stochastic element comes from random fluctuations in the environment rather than from genetic drift. The model is a direct extension of the one in the previous paper in this series (Gillespie, 1975) which dealt with a population which is subdivided into two patches with restricted migration between them.  相似文献   

14.
Michel Melou 《Geobios》1985,18(5):595-607
Since it is impossible to state about any genericassignment for Orthis berthoisiRouault, 1849the species name is herein restricted to original specimens figured by the author. The study of the Brachiopods from the St-Germain-sur-Ille Formation allows to confirm the first determination by De Tromelin &Lebesconte (1875)and to establish their conspecificity with Orthis berthoisi var. erratica described in 1869 by Davidson from the Budleigh-Salterton pebbles. The successive assignment of the species erratica to the genus Svobodaina(Cocks, 1978) then to Corineorthis(Cocks & Lockley, 1981) is discussed. The attribution to the genus DrabovinellaHavlicek, 1951appears most likely.  相似文献   

15.
A DNA binding protein with a molecular weight of 64,000(64DP) has been purified to homogeneity from human serum, and its quantitative assay has been developed. The average level of serum 64DP in 30 normal controls was 41.4 μg/ml, whereas it was 175 μg/ml in 87 patients with untreated malignant disease. Furthermore it was found to be elevated in all tested patients, 8 cases, with carcinoma in early stages. Serum 64DP has been found to be different from C3DP, CEA# or α-FP#, and it appears that this protein might prove to be a useful tumor marker in malignant diseases.  相似文献   

16.
Nosema pulvisPerez, 1905, Ameson pulvis (Perez) Sprague, 1977, in muscles of the crabs Carcinus maenas and C. mediterraneus from the coast of France, was observed with the electron microscope. It was found to be structurally similar to the type species A. michaelis (Sprague, 1970). Sprague, 1977, having moniliform sporogonial plasmodia, unikaryotic sporoblasts, and hirsute sporulation stages. It is treated as distinct from A. michaelis because it has slightly smaller spores (by comparison with syntype material of A. michaelis) and appears to have fewer coils in the polar filament. The results require the removal of the genus Ameson from the family Nosematidae Labbé, 1899, where Sprague (1977) had placed it under the erroneous supposition that its sporoblasts are diplokaryotic. Ameson is transferred to family Unikaryonidae Sprague, 1977. Ameson is distinguished from PereziaLéger and Duboscq, 1909, shown by Ormieres et al. to have a similar developmental pattern, by presence of appendages on its sporulation stage. A. nelsoni (Sprague, 1950), the third, and only other species of Ameson, lacks the appendages and is transferred to genus Perezia.  相似文献   

17.
18.
Michel Brunet 《Geobios》1979,12(5):653-673
A screen washed and hand sorted sample of six tons sediments from La Milloque (Lot-et-Garonne) has yielded to the author several thousand micromammal's teeth. Among the Rodents, four extinct species of Cricetids have been recognized: Eucricetodon praecursor (Schaub, 1925); Adelomyarion viretiHugueney, 1969; Pseudocricetodon cf. thaleri (Hugueney, 1969); Melissiodon quercyiSchaub, 1920. The fossil remain's study affords many paleontological informations more particularly for E. praecursor, a previously poorly known species. About the upper Oligocene biochronology the four species' evolution degrees prove the statute of reference locality attributed to La Milloque, «mammalian timemark just below the reference locality of Coderet (Allier). Moreover it's pointed out that the locality of Rickenbach (Switzerland) is slightly older than La Milloque, whereas an intermediate age between La Milloque and Coderet can be suggested for the locality of Dicupentale (Tarn-et-Garonne).  相似文献   

19.
Based on a model of the active site of myosin (Ramirez, Shukla &; Levy, 1978), a chemical mechanism for MgATPase and intermediate oxygen exchange is presented. In this mechanism, oxygen exchange takes place via an oxyphosphorane intermediate that undergoes double turnstile rotation (Ugi, Ramirez, Marquarding, Klusacek &; Gillespie, 1971; Ramirez &; Ugi, 1974. During hydrolysis by native skeletal muscle myosin, only three [18O] atoms from labelled water are rapidly incorporated into the phosphorus that is finally released to the medium as Pi; whereas, during hydrolysis by subfragment 1 (S1), which is the head of myosin, four oxygens are labelled rapidly. To explain this difference, we postulate that cleavage of the (S1)-(S2) hinge in the preparation of S1 modifies the interaction of the oxyphosphorane intermediate at the active site. This enables a normally non-exchangeable oxygen to enter the exchange process. This is consistent with our earlier interpretation to the effect that the active site and the hinge in myosin are relatively close to each other Shukla &; Levy, 1977b; Shukla &; Levy, 1978. We postulate that the major elements of the active site are situated on a 92 amino acid fragment, p10, isolated by Elzinga &; Collins, 1977 from myosin. P10 is now known to be situated in the region that connects the head to the body of a myosin heavy chain (Lu, Sosinki, Balint &; Streter, 1978). An examination of the p10 fragment for a possible point of proteolytic attack in the region of the hinge which will generate S1 revealed lysine 82. Breaking the protein chain at a point so close to the active site pocket could explain the effect of hinge cleavage on oxygen exchange. Two additional features of the present mechanism are: (1) the protonation of Pγ of a MgPα,Pγ complex of ATP, which depresses monomeric metaphosphate mediated hydrolysis, and enhances oxyphosphorane formation by addition of water to Pγ; (2) the coordination of Nτ-methylhistidinet2 of actin with Mg at the active site, which activates the release of the products of hydrolysis.  相似文献   

20.
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