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1.
Ale? Hrdli?ka's hypothesis on a Neandertal phase of human evolution is examined in light of current data and interpretations on Neandertals. Hrdli?ka's interpretations are related to his ideas regarding the peopling of the New World. A major early statement of Hrdli?ka's views on Neandertal was his Huxley Memorial Lecture of 1927. We assess this formulation and subsequent development of his hypothesis. Hrdli?ka's position is compared with the “presapiens” and “pre-neandertal” hypotheses on the basis of current theory and data.  相似文献   

2.
Hyperimmunization of B6.C-H-2bm?1 (H-2bm?1), a congenic mutant of C57Bl/6J (B6), with the C57Bl lymphoma EL4 resulted in the induction of antibodies with apparent EL4 specificity. EL4 reactivity was demonstrable in H-2bm?1 anti-EL4 sera by complement-mediated cytotoxicity, absorption, and enzyme-linked immunosorbent assay. By these same serological tests, H-2bm?1 anti-EL4 serum was found to be nonreactive with B6 normal lymphoid cells, embryonic fibroblasts, and two fibrosarcomas previously induced in B6 mice by methylcholanthrene. These data suggest that the serological response of H-2bm?1 to EL4 is directed against tumor-associated antigens on EL4. These findings indicate that congenic mutants which differ from the wild-type strain at MHC Class I subloci, but which do not evoke serological responses to MHC components, may provide convenient sources for preparing serological reagents directed against tumor-specific antigens.  相似文献   

3.
Fourteen species of Baptisia were compared serologically, using antiserum against B. nuttalliana. By means of both immunoelectrophoretic and double-diffusion techniques, it was possible to disclose 11 distinct arcs plus some weaker arcs, with few reliable (definite and repeatable) differences detected among the species of Baptisia investigated. Since the individual species of Baptisia are often quite distinctive, as judged by other chemical and morphological criteria, the serological data are in this instance conservative and appear to be effective in circumscribing the genus. In contrast, striking interspecific differences in the serological properties of unicellular green algae have been obtained (reported elsewhere) by similar techniques in this laboratory. It is concluded that serological data should be regarded as adjuncts to other systematic knowledge only on the basis of empirical manifestations of their utility. There is no clear justification for regarding serological data as intrinsically either superior or inferior to other systematic criteria.  相似文献   

4.
This study was designed to identify the rare?type?ABO?blood?groups, B(A) 02, from Eastern China. Three samples with discordant serological results during routine blood type identification and four samples from one sample’ family were selected. All of them were detected by serological method. The exon 6 and 7 of the ABO genes were amplified by PCR and sequenced. They were typed as AsubB by serology and as BO by genotype. In AsubB samples, nt 700C>G mutation was detected in B gene, which was previously defined as B(A)02 alleles. In these seven samples, six showed B(A)02/O01 and one showed B(A)02/O02.B(A)02 allele was found to be more common in this study than B(A)04 which is considered to be more frequent than B(A)02. The careful identification of rare blood types is important for the safety of clinical blood transfusion.  相似文献   

5.
Defined serological blood tests of deceased cornea donors are required to minimize the risk of viral infections of a transplant recipient as much as possible. Haemolysis, autolysis and bacterial contamination, may produce significant changes of post-mortem blood samples, which may lead to false serological test results. Pre- and post-mortem findings from the same cornea donors of the University Tissue Bank of the Charité in the years 2004-2009 (n?=?487) were retrospectively analyzed and compared. The test results from pre-mortem blood samples were defined as the reference for the post-mortem blood test. Of 487 cornea donors, there were a total of 21 cases (4.3?%) with discrepancies between serological test results from pre- and post-mortem blood samples. Of these, 7 values referred to the HBsAg-testing, 3 to the anti-HBs-, 1 to the anti-HBcIgG?+?IgM-, 1 to the anti-HCV-, 4 to the anti-HIV 1/2- and 5 to the TPLA-findings. False negative results within post-mortem serology occurred in 4 of 487 cases (0.8?%). False positive results within the post-mortem blood samples occurred at a much more frequent rate, with 17 of 487 cases (3.5?%). Discrepancies between serological pre- and post-mortem blood tests occur mainly due to the use of non-validated test systems. Therefore, it seems reasonable to test pre- and post-mortem blood samples serologically, whenever possible, at the same time, regardless of the sample age. Positive results, regardless of the sample type, should always be retested with validated confirmation tests (e.g. NAT), in order to differentiate between false and true positive results.  相似文献   

6.
Ora D. Canaani  Kenneth Sauer 《BBA》1978,501(3):545-551
The absorption and CD spectra of chloroplast fragments from spinach, barley and a barley mutant (chlorophyll b-minus) were studied at temperatures of 23°C and ?196°C. The CD spectrum of wild type barley and spinach at ?196°C showed troughs at 640, 653, 676 and 695 nm and a maximum at 667 nm. The CD spectrum of the barley mutant at ?196°C consisted of a large trough at 684 nm, a small trough at 695 nm and a positive peak at 670 nm. A new feature observed at ?196°C but not at 23°C is the trough at 640 nm. This 640 nm CD signal is missing in the CD spectrum of the barley mutant. It is attributable to the light-harvesting chlorophyll ab protein which appears to be missing in the mutant. Another new feature, the trough at 695 nm, was observed in the CD spectra of spinach, barley and the barley mutant at ?196°C. The 695 nm trough appears to be sensitive to detergents and it may be due to a labile chlorophyll a·protein complex. Possible interpretations of these data are discussed.  相似文献   

7.
Ten population samples from different geographic origins were tested serologically for the AG polymorphism of human beta-lipoproteins. Their haplotype frequencies were used with previously published data to perform a wide analysis of AG genetic differentiations throughout the world. Coancestry coefficients were computed from weighted F(ST)s among populations by using a matrix of molecular distances among AG haplotypes, which is here determined on the basis of DNA studies. Coancestry coefficients derived from unweighted F(ST)s and more classical Prevosti distances were computed on the same data and used for a comparison. In all cases a highly significant correlation was found between genetics and geography on a worldwide scale, while the significance of the correlation with linguistics differed. A test of significance of the pairwise F(ST)s among populations also gave different results depending on whether the molecular distance matrix among AG haplotypes was included. Globally, this study shows that in spite of being highly significantly correlated to each other, different genetic distance measures can lead to different interpretations of the same data set. Moreover, the elucidation of the molecular models related to the presently known serological polymorphisms may represent an additional tool for analyzing such polymorphisms in human population genetics studies.  相似文献   

8.
This article examines the provisions in the 2010 Russian–Norwegian Treaty on Maritime Delimitation and Cooperation in the Barents Sea and the Arctic Ocean dealing with the management of transboundary hydrocarbon resources. How compatible is the unitization mechanism in the Treaty with Russian and Norwegian legislation? Will there be tension between Russian and Norwegian interpretations? How does Russian and Norwegian legislation support or challenge the concept of a “unit operator” in a cross-border unitization? What are the possible concerns and pitfalls related to mechanisms for consultations and procedures for dispute resolution?  相似文献   

9.
Years of work with ionizing radiations have given us a wealth of data on radiation-induced mutations. These data, which have given insights regarding the mutational processes, should form the background for all mutagenesis work. In chemical mutagenesis, as in radiation mutagenesis, it is important to know the shape of the dose-effect curve in order to make further interpretations and calculations. It is also important to be on the constant alert for new relations that can be explored.  相似文献   

10.
Human serological profiles, and feline serological and fecal profiles were used to study the epidemiology of toxoplasmosis in Santa Clara County, California. The prevalence of human toxoplasmosis was determined to be 42.9% in a test population of 147 women. The prevalence of feline toxoplasmosis was indicated to be 34.8% based on serological analysis of 158 felines. Of 107 cats tested, 6.5% were shedding Toxoplasma gondii - like oocysts in their feces. Statistical analyses of questionnaire data indicated that the major infection sources for seropositive humans in this study were: (1) eating rare-medium cooked beef; (2) exposure to cats; and (3) working in an outside garden. Of these three sources, gardening represented the least risk. The data from questionnaires with reference to age, residence, and eating and toilet habits of owned felines were evaluated and found to show no significant statistical correlation with seropositivity. The infection sources for seropositive felines could not be determined. The plausible significance of feline-human interaction, human consumption of infected meat, and gardening habits is stressed.  相似文献   

11.
One of the aspects of antagonistic relations could be the competence of microorganisms for specific sites of attachement to the epithelium common for shigellae and some E. coli serological types; this was demonstrated on a model of shigella-induced keratoconjunctivitis and in experiments with the HEp-2 cells infected with H3-glucose-labeled Sh. flexneri 5a, with combined administration of the latter with E. coli 08 and 028. The data obtained emphasized the importance for the development of the infectious process of the primary stage of shigella attachment to the epithelium. It was also revealed that the presence of common pili in the strains or production of colicine by bacteria intensified the antagonistic activity of E. coli, irrespective of their serological type.  相似文献   

12.
用免疫电镜技术研究长叶车前花叶病毒株系的血清学关系   总被引:3,自引:0,他引:3  
徐均焕 《病毒学报》1992,8(2):174-178
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13.
猪繁殖与呼吸综合征病毒(PRRSV) Nsp7蛋白具有较强的免疫原性,且在美洲型(NA)和欧洲型(EU) PRRSV之间免疫原性差异显著,是抗体分型检测的理想靶抗原.本研究采用原核表达系统分别表达和纯化了NA和EU PRRSV Nsp7蛋白,Western blotting分析表明重组蛋白与相应血清型抗体有较强的免疫反应,但特异性较差,与另一血清型抗体仍存在一定的免疫反应,预示两种血清型PRRSV Nsp7蛋白存在免疫交叉反应抗原表位,全长表达不能用于分型诊断.利用生物学软件分析NA和EU PRRSV Nsp7的相似抗原表位,采用融合PCR缺失其编码序列后,经表达纯化获得NA-△Nsp7和EU-△Nsp7两种截短蛋白,蛋白大小约为43 kDa,Western blotting分析表明NA-△Nsp7和EU-△Nsp7可分别与相应血清型抗体发生特异性反应,且无免疫交叉反应,为NA和EU PRRSV分型抗体检测试剂的研制奠定了基础.  相似文献   

14.
Antibodies isolated from antiserum against plant viruses were labeled with the isotope35S as follows: the mixture of antibodies with radioactive cysteine hydrochloride was allowed to stand for half an hour, run on a Sephadex G-25 column and individual fractions were collected. Sephadex G-50 bed was equilibrated and washed with saline (0,85 % NaCl) phosphate buffer (0,01 m) pH 7,2. Fractions showing the highest radioactivity and at the same time the most evident serological reaction were combined and used as35S labeled antibodies. The labeled antibodies were used for rubbing leaves; the leaves were afterwards incubated, washed, killed, dried and then subjected to autoradiography. The method of indirect serological reaction also proved to be very good. Using this method, pig gamma globulin against rabbit gamma globulin was labeled with35 S; this labeled gamma globulin was then used to detect serological reaction on leaves between the virus and homologous rabbit antiserum and/or antibodies. The results of those reactions were also determined by autoradiography. Exact procedure for labeling antibodies, carrying out serological reactions and autoradiography is desribed.  相似文献   

15.
Although several investigators have presented data suggesting that the Caprifoliaceae is polyphyletic in origin, the family has been retained as a taxon in recent classifications. Serological analyses of the taxa included within the family have been undertaken to provide additional taxonomic data. Precipitin techniques of double diffusion (Ouchterlony) and nephelometry (Boyden Procedure) were used to analyse serological similarities of seed proteins from representatives of the family. Three distinct groupings were detected for the taxa included in the Caprifoliaceae. AlthoughViburnum exhibited greatest serological similarity withSambucus, Viburnum was quite distinct from all members of the family investigated.Sambucus also was somewhat distinct from the other genera and exhibited about as much serological correspondence withCornus of the Cornaceae as with any tested member of the Caprifoliaceae. The remaining species examined formed a very close serological grouping. These data can be interpreted as supporting either a monophyletic or polyphyletic origin of the family as presently composed, because of the different arrangements of the families Caprifoliaceae and Cornaceae in the various systems of classification.  相似文献   

16.
The authors present the results of study of the serological properties of 46 strains of saprophytic leptospirae of different origin. On the basis of the affinity of the antigenic structure detected in the cross microagglutination reaction (MAR) 38 strains under study were united into 8 serological groups; the rest 8 strains were serologically independent in this reaction. The fact that 9 strains of water leptospirae isolated in the Armenian SSR belonged to one serological group was proved in the cross MAR and the test of aglutinin adsorption. This serological group was new and was named L. armenica. Five individual serological types of saprophytic leptospirae were differentiated in its composition. Comparative study of the serological interrelations between the group of strains isolated in Armenia and the strains of some serological groups and serological types the closest serological connections were noted in the K-1030 (serological group Armenica) and Bovedo (serological group Andamana) strains. It is believed that the existing division of the saprophytic leptospirae into two serological groups (Semaranga and Andamana) required widening and supplement by new serological groups and serological types.  相似文献   

17.
Our goal in this review is to explore the relationship between Drosophila and vertebrate neural stem cell development by comparing progress in each system with the aim of answering several central questions in stem cell biology: (a) How are stem cells formed? (b) Do stem cells divide symmetrically or asymmetrically? (c) How is stem cell fate maintained? (d) How is stem cell differentiation initiated? (e) How are different stem cell fates determined? (f) How “plastic” are different neural stem cell fates? (g) How do neural stem cells produce different progeny? and (h) What regulates stem cell proliferation versus quiescence? Not surprisingly, research in Drosophila and vertebrate systems each have their own biases, strengths, and weaknesses; we hope that by directly comparing progress in each field, new experiments and interpretations in both vertebrate and Drosophila research will become apparent. It has become increasingly clear that vertebrates and Drosophila share many fundamental mechanisms of neurogenesis, validating a comparative approach. © 1998 John Wiley & Sons, Inc. J Neurobiol 36: 111–127, 1998  相似文献   

18.
BackgroundAs prevalence decreases in pre-elimination settings, identifying the spatial distribution of remaining infections to target control measures becomes increasingly challenging. By measuring multiple antibody responses indicative of past exposure to different pathogens, integrated serological surveys enable simultaneous characterisation of residual transmission of multiple pathogens.Methodology/Principal findingsHere, we combine integrated serological surveys with geostatistical modelling and remote sensing-derived environmental data to estimate the spatial distribution of exposure to multiple diseases in children in Northern Ghana. The study utilised the trachoma surveillance survey platform (cross-sectional two-stage cluster-sampled surveys) to collect information on additional identified diseases at different stages of elimination with minimal additional cost. Geostatistical modelling of serological data allowed identification of areas with high probabilities of recent exposure to diseases of interest, including areas previously unknown to control programmes. We additionally demonstrate how serological surveys can be used to identify areas with exposure to multiple diseases and to prioritise areas with high uncertainty for future surveys. Modelled estimates of cluster-level prevalence were strongly correlated with more operationally feasible metrics of antibody responses.Conclusions/SignificanceThis study demonstrates the potential of integrated serological surveillance to characterise spatial distributions of exposure to multiple pathogens in low transmission and elimination settings when the probability of detecting infections is low.  相似文献   

19.
A circulation at the territory of the country of various biochemical and serological variants of escherichia belonging to serological group O1, isolated in acute intestinal diseases of children and adults, was revealed. Nonhomogeneousness of the partial composition of the O-antigen was demonstrated; K-antigens were determined; new H-antigens were described. Of the 10 serological types of escherichia there proved to prevail O1 : K? : Hp and O1 : K1 : Hp; in group and sporadic acute intestinal diseases there were for the first time isolated O1 : K1 : H34, O1 : K1 : H20, O1 : K1 : Hp, O1 : K51 : H7, and O1 : K? : H20.  相似文献   

20.
Streptococci isolated from the dental plaque of five animal species were identified by physiological and serological methods. Twenty-nine strains of streptococci considered to resemble Streptococcus mitior or Strep. bovis on the basis of physiological data reacted with Lancefield group B or group K antisera respectively in tube precipitation tests. Further serological studies with standardized antigens from known serogroup B and K streptococci revealed that only three of these 29 isolates had been serogrouped accurately and carried the appropriate group antigen. Comparisons were made between the reactivity of the antisera produced by Difco and Wellcome Reagents with acid and autoclaved extracts of the strains. It was shown that the accuracy of serogrouping such isolates could be improved if the tests were made in a gel diffusion system that included a reference antigen.  相似文献   

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