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1.
Summary The histochemical activities of succinic dehydrogenase (SDH), myofibrillar Adenosine triphosphatase (ATPase) and alpha glycerophosphate dehydrogenase were studied in serial sections of rat vastus lateralis (red) (RVL), gastrocnemius and diaphragm muscles. Three main fibre-types were distinguished. The Type I fibres of RVL and gastrocnemius muscles fell into two distinct groups: one category-Type IA showed very low ATPase activity. The second category of Type IB fibres displayed moderate ATPase reaction. The Type IA fibres were divisible into two sub-groups when tested for SDH reaction. Type IA1 fibres possessed a homogenous distribution of diformazan·granules throughout the fibre: Type IA2 fibres displayed characteristic moth-eaten pattern of diformazan localization. The diaphragm muscle did not show either Type IB or Type IA2 varieties. The great majority of Type I fibres were sub-type IA1 in the three fast muscles studied. It is also demonstrated here that an inherent heterogeneity exists between Type I fibres of diaphragm and leg muscles in regard to -GPD localization. This histochemical data emphasizes the fact that subdivision of Type I striated muscle fibres of mammalian animals into two sub-types is only approximate and that a further subcategorization is possible.  相似文献   

2.
Biology cannot accommodate all aspects of culture. Aspects of culture that a biological approach can take into account can be covered by the biological categories of phenotype and environment. There is no need to treat culture as a separate category. Attempts to elaborate biological explanations of cultural variation will meet with success only if biologists expand theories of development, and integrate them in evolutionary biology. The alternative — elaborating the idea of so-called cultural inheritance — makes little sense from a biological point of view.  相似文献   

3.
Assignment of human ferritin genes to chromosomes 11 and 19q13.3→19qter   总被引:10,自引:0,他引:10  
Worwood  M.  Brook  J. D.  Cragg  S. J.  Hellkuhl  B.  Jones  B. M.  Perera  P.  Roberts  S. H.  Shaw  D. J. 《Human genetics》1985,69(4):371-374
Summary Extracts of hamster-human and mouse-human hybrids, some with translocations involving chromosome 19, have been assayed for both human spleen ferritin (rich in L subunits) and human heart ferritin (rich in H subunits). Hybrid lines retaining part of the long arm of chromosome 19 including the region 19q13.319qter produced human L type ferritin. This confirms the previous assignment of the ferritin gene to chromosome 19 (Caskey et al. 1983). However, lines retaining chromosome 11 were found to contain human H type ferritin suggesting that the gene for the H subunit is on this chromosome. The presence of chromosome 6 was not necessary for the expression of either H or L type human ferritin. It thus seems unlikely that the gene for idiopathic haemochromatosis is a ferritin gene.  相似文献   

4.
Contrary to other reports, we have found that the A type G6PD found in two permanent cell lines—HeLa (Gey), with its single cell clonal derivative HeLa S3, and Detroit 98, with its four clonal derivative lines—is not a single variant but rather at least three different isozymes. One is heat stable with normal specific activity and normal A type electrophoretic migration, another is heat labile with normal specific activity and normal A type electrophoretic migration, and the third is heat labile with reduced specific activity and slightly slow A type electrophoretic migration. We also found that in a mosaic cell population with respect to G6PD phenotype, the predominant G6PD phenotype varied randomly over a 5-month period, that the G6PD phenotype might be mutable in permanent cell lines, and that spontaneous human cell lines might not be HeLa cell contaminants as has been suggested.Aided by the National Institutes of Health General Research Support Grant # 5 S01 FR05507.  相似文献   

5.
Zusammenfassung Das Zetern der Amseln wurde von 1969 bis 1972 in einem sehr regelmäßig besetzten Revier automatisch registriert. Sowohl das Zetern sämtlicher registrierter Amseln, als auch das Zetern bestimmter Individuen gehorchen den meisten Aschoff'schen Regeln. Zwischen Individuen sind die Zeteranfänge äußerst unterschiedlich, die Zeterenden dagegen nicht. Die individuellen Zeteranfänge reichen in der Vergleichszeit von ca. 50 min bis 20 min vor Sonnenaufgang (Mittelwerte für 1/3 Monat).
The alarm-call activity of the Blackbird
Summary In a very regulary occupied district the alarm-call (Zetern) of blackbirds was automatically recorded from 1969 till 1972. The Zetern of all recorded blackbirds as well as the Zetern of single individuals obey to most of Aschoff's rules. Among the individuals the beginnings of the Zetern are extremly different, but not the endings of the Zetern.The interindividual beginnings of Zetern in the comparable time reach from about 50 min. to about 20 min. before sunrise (mean values for 1/3 of a month).
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6.
Zusammenfassung Mischungen aus dem Mycel sweier weißer oder zweier brauner Stämme des Kulturchampignons hatten keinen Einfluß auf den Fruchtkörperetrag.Bei Mischungen aus einem weißen und einem braunen Stamm was dagegen der Ertrag immer niedriger als erwartet und das Mycel verschwand verhältnismäßig schnell. Der Ertragsausfall beruht in der Regel auf einer Unterdrückung des braunen Stammes.Herrn Prof. von Sengbusch zum 65. Geburtstag in Dankbarkeit und Verehrung gewidment.  相似文献   

7.
The purpose of this study was to investigate whether subjects who self-report high levels of stress have lower immunity, and whether low-immunity subjects under high stress could enhance phagocytic activity through biofeedback-assisted relaxation (BAR). During Phase 1, the level of stress and the level of phagocytic immune functioning (nitroblue tetrazolium test) were assessed as high or low. Significant chi-square analysis (x2=3.8624, df=1, p<.05) showed that subjects with high stress had low immunity. Sixteen high-stress, low-immunity subjects were randomly assigned to BAR and control groups during Phase 2. Following treatment, NBT changes showed significant increases (F=11.11, p<.003) for experimental group as compared to control group. White blood cell count and white blood cell differential were unchanged across blood samples for both groups. Experimental subjects reported significant decreases in tension-anxiety and increases in overall coping. BAR was concluded to have improved coping skills and phagocytic capacity. BAR affected the quality, rather than the quantity, of phagocytic neutrophils.  相似文献   

8.
Alcántara  O.  Luna  I.  Velázquez  A. 《Plant Ecology》2002,161(2):167-174
Mexican cloud forest vegetation has been recorded in temperate humidconditions at rather different elevations ranging from 600 to 3000m. They are characterised by high biodiversity under continuousfoggy situations. Some authors state that many genera are quantitativelyimportant to depict cloud forest conditions. Detailed quantitative studiescomprising most of the localities of Mexican cloud forests to depict altidudinaldistribution ranges on basis of preferential genera have not been previouslyconducted. The aim of this study is (1) to recognise characteristic preferentialgenera of Mexican cloud forest conditions, and (2) to determine quantitativelythe current altitudinal distribution pattern of this vegetation type. From adatabase composed by 995 genera inhabiting in the Mexican cloud forests, sixgenera were chosen preliminary as preferential characteristics. These wereClethra, Magnolia, Meliosma, Styrax, Symplocos, andTernstroemia. These genera include 70 species that occur atover 70% of the current Mexican cloud forest fragments. The mean elevation ofthese genera records were 1853 m (±600 at 95% confidenceinterval). The results showed that Mexican cloud forests occur optimally between1250 and 2450 m. Additionally, Mexican cloud forest is the bestdistributed within some provinces of the Región Mesoamericana deMontaña, chiefly at Serranías Meridionales,Sierra Madre Oriental, and SerraníasTransístmicas. The results are discussed in light of theimportance of these regions as diversification centres.  相似文献   

9.
Mauritania: A neocolonial desert   总被引:1,自引:0,他引:1  
Conclusion The Mauritanian ruling class, imposed upon the masses in 1960, continued to be assisted and advised by French cooperants techniques in the post-colonial period working closely with international finance capital, and have been promising their subjects that the construction of their society depended on the successful operation of multinational cooperation, represented in the country by MIFERMA and SOMIMA. By the 1970's it became clear to the majority of the Mauritanian people that these foreign firms were carrying out the systematic pillage of their resources rather than stimulating the development of their country; and that the rapid growth of the extractive sector was part of a radical process of peripherization, which has woven the Mauritanian economy and society into the capitalist center. Moreover, external economic aid pushed the neo-colonial state into the debt trap. Accordingly, Bonte observed that while production apparently increased and while private capital certainly flowed into the country, it flowed out in even larger quantities. These flows led to a persistent deficit in the balance of payment and to a growing debt [95]. This trend has been worsening in recent years. Without loans from European, American, and conservative Arab regimes, the neo-colonial state would have collapsed financially. Indeed, from 1970 to 1975, foreign loans provided between 75 and 90 percent of the funds for the governmental development programs [96].The social conditions of the people drastically worsened in the 1970's. For instance, in 1976 a government official admitted that only 15 percent of the total population received medical attention. Moreover, the activities of the multinational corporations have destroyed the supportive communal structures of the rural masses which, in the past, have minimized the consequences of drought and other economic crises. When the 1969–74 drought occurred, innumerable droughtstricken nomads and subsistence agriculturalists found themselves helpless and completely destitute. Confronted with such as state of affairs, they had no alternative but to flee to the mushrooming slums surrounding the urban centers, there to lead mutilated and mutilating lives.For these masses neither Mauritanianization nor nationalization have prevented their growing immiseration. The extractive activities, whether under the aegis of multinational corporations or state-owned companies, which remain dependent on finance capital and its market, cannot resolve the fundamental problems of the Mauritanian people. On the contrary, the operations of these foreigndominated companies negate the possibility of a liberating, diversified industrial process that relies on, assesses and takes into account the primary needs of the people. Only an industry that results in large employment effects generated in proportion to the amount of capital invested and whose management is assumed to a large degree by the producers themselves, can achieve deep development of a country like Mauritania. Extractive industry controlled by multinational corporations cannot generate positive linkage effects [97] to the local economic sectors powerful enough to effectuate their development within a well-planned, culturally integrated, and economically fruitful national social economy. A neo-colonial state of the Mauritanian type — ruled by a class that owes its ascension to power to a retreating colonialism — formed as a mediating mechanism for prolonging the foreign exploitation of its own resources — cannot resolve the basic problems of the people. In short, when the iron ore of Mauritania is worked out, that country will go back to the desert [98]. However, this observation by Amin is apocalyptic, pessimistic, and dangerously deterministic. Another, more viable, more human, alternative is for the northwestern African peoples to extricate themselves from the world capitalist system, and its local comprador bourgeois allies. They must find a way to dis-establish the neo-colonial, inviable statelets and replace them with a confederation of socialist republics devoted to the elimination of exploitation and the construction of authentic national cultures.Mahfoud Bennoune is Assistant Professor of Anthropology at Stockton State College, Pomona, New Jersey.  相似文献   

10.
Molecules of deoxyribonucleic acid and synthetic polydeoxyribonucleotides (NA) in the particles of liquid-crystalline dispersions resulting from interaction with chitosan are accessible to interaction with intercalators. The intercalation is accompanied by alteration in the direction of spatial twist of cholesterics of NA–chitosan complexes. This effect is absent in the case of classical cholesterics produced from NA molecules via phase exclusion, i.e., the cholesteric structure of NA–chitosan complex is very labile as distinct from classical cholesteric NA.  相似文献   

11.
In the present report, we used serological, cellular, and restriction fragment length polymorphism (RFLP) to investigate the DR1 haplotype in the Israeli population. We describe an Israeli homozygous typing cell (HTC), HLA-DwLVA, which defines a new lymphocyte-activating determinant associated with Bw65, DR1 and distinct from Dwl. The parents of this donor, non-Ashkenazi Algerian Jews, are first cousins and share HLA-Cw8, Bw65, BfS, DR1, DQw1, DPw4. No specificity could be assigned to HLA-DwLVA using the 91 Ninth Workshop HTCs. Two families and forty unrelated DR1 individuals were studied with DwLVA and a panel of DR1/Dw1 HTCs. HLA-DwLVA showed segregation as a single determinant within families. This new specificity was present in 24 out of 40 (60%) unrelated DR1 individuals, indicating that in the Israeli population DwLVA is the main lymphocyte-defined determinant associated with the serologically defined DRI specificity, in contrast to non-Jewish Caucasoids where DR1 is significantly associated with Dw1. The vast majority of DwLVA-positive carriers were also Bw65 carriers, indicating that Bw65, DR1, DwLVA may represent a typical allele combination in the Israeli population. The RFLP analysis established the correlation of certain RFLPs with Dw1 and DwLVA. In addition, we describe a cluster of RFLPs that may correspond to a new Dw subtype associated with DR1, for which no serological and cellular reagents have been described so far.  相似文献   

12.
    
In vitro folding studies of several proteins revealed the formation, within 2–4 msec, of transient intermediates with a large far-UV ellipticity but no amide proton protection. To solve the contradiction between the secondary structure contents estimated by these two methods, we characterized the isolated C-terminal fragment F2 of the tryptophan synthase 2 subunit. In 2, F2 forms its tertiary interactions with the F1 N-terminal region. Hence, in the absence of F1, isolated F2 should remain at an early folding stage with no long-range interactions. We shall show that isolated F2 folds into, and remains in, a state called the pre-molten globule, that indeed corresponds to a 2- to 4-msec intermediate. This condensed, but not compact, state corresponds to an array of conformations in rapid equilibrium comprising native as well as nonnative secondary structures. It fits the new view on the folding process.  相似文献   

13.
In the ascophoran bryozoanCryptosula pallasiana (Moll) many examples of regenerative growth and of abnormal zooids have been observed. Most of the different forms of monsters are caused by fusion of zooids or zooid buds respectively. Zooids may often fuse laterally but in a few cases also distally. Some monster zooids have two polypides and combined opercula caused by various degrees of fusion of the apertures. Lack of sufficient space may lead to the formation of dwarf zooids or remainder cystids.  相似文献   

14.
Summary Two intracapillary (IC) media feed protocols termed media rich and media lean were examined in an effort to understand the effect of this variable on hollow fiber cell cultures. The media rich protocol emphasized a high volume IC media per day (5 liters) containing no serum and a normal amount of extracapillary (EC) media serum (10% v/v). Alternatively, the media lean protocol used up to 1.0 liter of IC media per day containing 5% v/v serum and increased EC media serum (20% v/v). Both protocols produced substantial amounts of antibody in 25 days using HFN7.1 hybridoma cells (ATCC CRL 1606), however the media rich protocol produced twice as much antibody as the media lean protocol. The metabolism of the cells was dramatically different as measured by glucose uptake rate (GUR) with media lean cells having a six-fold lower GUR. Our results indicate that the media rich protocol is useful for producing larger amounts of antibody in a short time frame. The media lean protocol may be considered when the production costs of antibody, particularly media and serum, is the overriding concern.  相似文献   

15.
Summary The incidence of myosatellite cells associated with white and red muscle fibres of the parietal muscle and red fibres of the craniovelar muscle was estimated by quantitative electron microscopy in the Atlantic hagfish (Myxine glutinosa, L.). Myosatellite cell nuclei constitute 3, 11 and 23 % of the total number of nuclei inside the basal lamina of the three types of muscle fibres, respectively. However, the total number of nuclei is highest in white fibres, most of the nuclei belonging to striated muscle cells. Myosatellite cell profiles in transverse sections constitute 23, 41 and 61 % of the number of muscle fibre profiles of the three types, respectively. The intervals between adjacent myosatellite cells are 135 m in white fibres, 55 m in red parietal fibres, and only 25 m in craniovelar fibres. Since craniovelar fibres are also comparatively thin, myosatellite cells constitute a significant fraction of the volume inside the basal lamina in these fibres. The myosatellite cells are 30–50 m long and up to 5 m thick. Some myosatellite cells possess few organelles, whereas others appear to contain many free ribosomes, granular endoplasmic reticulum, prominent Golgi apparatus and lysosome-like bodies.This investigation was supported by the Norwegian Research Council for Science and the Humanities (NAVF grant No. C20.30–37). The authors are indebted to Jorunn Line Vaaland and Berit Branil for technical assistance, and to Dr. Finn Walvig, Biological Station, University of Oslo, Drøbak, for supplying the hagfish  相似文献   

16.
Two different twodimensional cellulose thinlayer separations for blocked, methylated mRNA 5-termini are described. They allow rapid analysis even of complex mixtures of mRNA cap structures on the basis of their methyl group content and base composition. These simple procedures are especially useful for the analysis of [3H-methyl]-labeled mRNA in combination with tritium fluorography. A qualitative and quantitative analysis of the methylated cap structures of in vitro labeled Vaccinia core mRNA is presented. The presence of methylated cap structures in Vaccinia RNA increases the in vitro translation efficiency of methylated Vaccinia RNA over Vaccinia RNA transcribed in the absence of a methyl group donor.  相似文献   

17.
Summary Intestinal lipid absorption and transport were investigated in albino rats. The observations point towards the existence of a continuity between plasma membrane invaginations and elements of the Golgi complex on its mature face. They also suggest a segregation of lipid droplets by paired Golgi membranes and plasma membrane invaginations. The following way for lipid transport is deduced: lipid droplets moving inside the smooth endoplasmic reticulum accumulate progressively and are condensed in Golgi cisternae of the forming face. Their limiting membrane ruptures and liberated lipid droplets are segregated by paired Golgi membranes of the mature face or by plasma membrane invaginations. Subsequently the inner of the two segregating membranes disappears while the lipid droplet is moved towards the intercellular space inside a canal communicating with this space. The suggestion is made that the Golgi apparatus is of double origin: one component representing a terminal plication of the endoplasmic reticulum; the second one—a terminal plication of the plasma membrane invagination. This concept explains the ultrastructural and histochemical differences between Golgi membranes of the forming and mature faces of the complex.  相似文献   

18.
This paper explores the usefulness of a concept of human behavioral breakdowns for studying psychiatric phenomena from a cross-cultural standpoint. The kinds of conceptualizations that are available in the English literature about human behavioral breakdowns across societies are reviewed. The way these breakdowns have been handled in the Western European Tradition of medicine is given special emphasis. Attention is focused on schizophrenia as one of the modern disease concepts of psychiatry that is a variant of human behavioral breakdowns. The essay then looks at schizophrenia using contemporary ideas about cultural relativism as these apply to the study of psychiatric phenomena in relation to society. Perspectives about the variable as versus the invariant in schizophrenia are reviewed.  相似文献   

19.
Summary Fundamentally, theoretically, there is only one process underlying genetic and cultural evolution: natural selection. Organism fitness-enhancement (adaptive significance) is one of its practical mechanisms; group formation and maintenance is another, often but not always through fitness-enhancement; and need-fulfillment is still another. If Durham can accept that formulation, and switch from organism-thinking to instruction-thinking (Cloak, 1975: 178), he will free himself from two handicaps: First, he can forget his worries about reductionism and determinism (1976a: 100, 101). Under this general theory of natural selection, cultural evolutionis biological evolution, continued by other (nongenetic) means. Second, he will spare himself the appearance of anthropomorphism, mentalism, and wishy-washiness attendant on his discussion of kinds of significance, other than adaptive significance, of cultural behaviors (1976a: 102–106, 115).  相似文献   

20.
Summary The temporal muscles of the guinea pig show a sexual differentiation reflected in their histochemical enzyme pattern. Using histochemical methods for mitochondrial (SDH, -GPDH), and glycolytic enzymes (phosphorylase, LDH) it could be shown, that in adult animals the male muscle is a white muscle with marked activity of glycolytic enzymes, the female muscle a red muscle displaying high activity of mitochondrial enzymes. This differential enzyme pattern can be converted by the application of testosterone to the female type during the postnatal development. The male sex hormone thus affects the histochemical enzyme pattern of the muscle, converting the red, female into a white, male muscle in the female guinea pig.  相似文献   

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