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1.
The K system in pigs included at least 6 internationally recognized blood group factors (Ka, Kb, Kc, Kd, Ke and Kf) controlled by the following alleles: Kacef, Kacf, Kade, Kae, Kbf and K- ( Andresen, 1963; Brucks 1967, Hojný et al. 1967, Saison 1967, Hojný, Hradecký & Pazdera, 1979). This paper describes the results obtained with a new antiserum, Kg, by which subgrouping of the Kade allele into Kade or Kadeg is possible.  相似文献   

2.
Linkage studies of three-point crosses (triple backcross matings) showed that the linear sequence of three of the pig's immunogenetic traits — the SLA major histocompatibility complex and the J and C blood group loci — is SLA-J-C . Andresen & Baker (1964) and Rasmusen (1965) described close linkage between the J and C blood group loci and respectively found their recombination frequency to be 5.29 ± 1.1 % and 7.00 ± 3.4 %; by combining the data the exact frequency was determined at 5.75 ± 0.79 % (Muir & Rasmusen, 1974). Later, linkage of the SLA major histocompatibility complex with both J (Hruban et al., 1976) and C (Hruban et al., 1977) erythrocytic loci was found. The maximum tabular lod score values were found in the recombination fraction Θ= 0.10 in comparison of SLA and J and in the fraction Θ= 0.20 in comparison of SLA and C (Hruban et al., 1977).  相似文献   

3.
Previous investigations have clearly shown the existence of associations between halothane sensitivity, the H blood group system and the PHI enzyme system in pigs (Rasmusen & Christian 1976, Jørgensen et al. 1976). These associations which have considerable practical interest are most probably linkage phenomenons (Jørgensen 1977, Andresen & Jensen 1977). The major recessive locus for halothane sensitivity (HAL) comprises the two alleles N and n, n being responsible for halothane sensitivity. The distances between this locus and the loci for H and PHI are still not known exactly. This communication aims at clarifying these problems.  相似文献   

4.
根据江苏泰县N-4井五通组观山段顶部的胞石Grahnichitina pilosa的发现,确定观山段的时代为中泥盆世吉维特期。据此认为:擂鼓台段的两层暗色泥岩,应分别对比为南洞页岩、长顺页岩;中泥盆世大海侵时,华南海沿苏皖河经皖南、苏南入侵苏北。对Grahnichitina pilosa进行描记和讨论。  相似文献   

5.
P E Crossen 《Humangenetik》1975,27(2):151-156
The banding patterns of chromosomes from 20 patients with chronic lymphocytic leukaemia (C.L.L.) have been analyzed. 97 of 100 metaphases examined had a normal banding pattern. The 3 remaining metaphases, all from one patient had bands similar to those seen after aging. It is concluded that the chromosomes in C.L.L. have normal banding patterns. The majority of cytogenetic studies in chronic lymphocytic leukaemia have reported normal chromosomes (Fitzgerald and Adams 1965; Oppenheim et al., 1965; Lawler et al., 1968). An inherited abnormality of G group chromosome (No. 22) has been reported in a family, three members of whom developed C.L.L. (Fitzgerald and Hamer, 1969), but further investigations of cases of familial leukaemia failed to reveal a similar abnormality (Fitzgerald et. al., 1966). The development of new techniques which allow the positive identification of individual chromosomes (Caspersson et al., 1969; Dutrillaux and Lejeune, 1971; Sumner et al., 1971; Seabright, 1971), has revolutionised human cutogenetics and revealed additional information regarding chromosome abnormalities and leukaemia (Rowley, 1973; Lobb et al., 1972; Milligan and Garson, 1974). The purpose of this investigation was to determine whether the chromosomes in C.L.L. have normal banding patterns.  相似文献   

6.
Besprechungen     
Book Reviewed in this article: Osche, G. (1966): Die Welt der Parasiten. Frisch, Karl v. (1965): Tanzsprache und Orientierung der Bienen. Reichenbach-Klinke, H. H. (1963): Krankheiten der Reptilien. Reichenbach-Klinke, H. , und E. Elkan (1965): The principal diseases of lower vertebrates. Griffin, D. R. (1964): Bird migration, the biology and physics of orientation behavior. Kaestner, A. (1965): Lehrbuch der Speziellen Zoologie. Kühn, A. (1965): Vorlesungen über Entwicklungsphysiologie. Lorenz, K. (1966): Stammes- und kulturgeschichtliche Ritenbildung. Hafez, E. S. (1962): The Behaviour of domestic animals. Hassenstein, B. (1965): Biologische Kybernetik. Bally, G. (1966): Vom Spielraum der Freiheit. Strohmeyer, C. (1959): Schweinekomödie.  相似文献   

7.
Dixon  L. K.  Nelson  B. A.  Priest  R. L. 《Genetica》1984,52(1):63-68
Mice of the genus Peromyscus all have 48 chromosomes. Yet the appearance of the 48 chromosomes is highly variable from species to species (Hsu & Arrighi, 1966, 1968, 1971; Pathak et al., 1973) and even in different populations of the same species (Sparkes & Arakaki, 1966; Ohno et al., 1966; Hsu & Arrighi, 1968; Arakaki et al. 1970; Te & Dawson, 1971; Bradshaw & Hsu, 1972; Murray & Kitchin, 1976). The evolutionary significance of this variation and the mechanisms for its initiation and maintenance have been of interest for quite a few years. However, it was not until the sophisticated chromosome banding techniques became available that mammalian cytogeneticists were able to begin to study the chromosome variation of Peromyscus in some detail. The use of C-banding led Hsu & Arrighi (1971) to the finding that the short arms of chromosomes in three different species of Peromyscus contained constitutive heterochromatin. These results suggested that the variations in the number of acrocentric chromosomes in Peromyscus might be a result of different amounts of heterochromatin. Later studies (Duffey, 1972; Waterbury, 1972; and Pathak et al., 1973) were also consistent with this hypothesis.However, it was soon discovered that not all chromosomal differences among Peromyscus populations are due to heterochromatin changes. Studies by Arighi et al. (1976) and Murray & Kitchin (1976) showed that some chromosomal differences between species and subspecies of Peromyscus are due to pericentric inversions. Thus, it appears that both inversions and the addition of heterochromatin are involved in the evolution of the karyotype of Peromyscus.The purpose of our study was to investigate the chromosomes of Peromyscus maniculatus in different populations in Colorado (U.S.A.) and to test for relationships involving an altitudinal gradient. In the first part of this study, orcein stained chromosomes from three subspecies of mice sampled at nine different altitudes were examined for karyotype variability. In the second part of the study, karyotypes of two subspecies (P. m. rufinus and P. m. luteus), representing high and low altitude populations were examined with Q banding to determine the mechanisms responsible for chromosomal differences.  相似文献   

8.
Though several agents may be involved in the etiology of enzootic pneumonia of pigs, recent investigations seem to indicate that the great majority of cases are caused by a Mycoplasma species — called M. suipneumoniae in Britain (Goodwin et al 1965) and M. hyopneumoniae in the U.S.A. (Maré & Switzer 1965).  相似文献   

9.
Several successful attempts have been made to induce swine dysentery in pigs using pure cultures of Treponema hyodysen-teriae (Taylor & Alexander 1971, Harris et al. 1972, Akkermans & Pomper 1973, Hughes et al. 1975). In these studies, either conventional or specific-pathogen-free pigs were used. In the present study, 2 approximately 8 weeks old conventional pigs (Nos. 1 and 2) were purchased and fed the same basic ration as used by Teige et al. (1977). In addition, 10 % cod liver oil was incorporated in the diet at each feeding. After a feeding period of 25 days rectal swabs were applied and examined for the presence of spirochaetes. The pigs were then fed a 3 days old primary and pure culture of T. hyodysenteriae on TSA-S400 medium (Songer et al. 1976). The culture originated from the colon of a pig with swine dysentery (Pig No. 4, Teige et al. 1977). Each pig received the agar contents of 5 petri dishes which were mixed with the food.  相似文献   

10.
Aquatic hyphomycetes on submerged fallen leaves and deadwoods have been numerously reported in fast running streams in temperate countries(Ingold,1976;Ingold,1979;Chauvet,1990;Barlocher & Rosset,1987;Barlocher et al.,1995;Descals et al.,1995).However,documented information is considerably limited in African countries(Ingold,1956;Dixon,1959;Le-John,1965;Ferreira et al.,1981),and unavailable in Cameroon,a country mostly covered with heavy tropical forests(Loung,1980).This paper is to present a list of aquatic and aeroaquatic hyphomycetes identified from foam samples collected in Cameroon during a two-year survey.  相似文献   

11.
A scheme for constructing computer models of motorneurons is presented. These model neurons display both repetitive firing and action potentials of appropriate time course; the technique combines ideas of Dodge and Cooley (1973) and Kernell and Sjöholm (1972, 1973). This scheme is used to construct models of motorneurons of different input resistance (and hence different geometry) in order to examine Kernell's (1966) observations that (a) small motorneurons require a lower injected current to begin firing than do large motorneurons; but (b) the slope of the injected current-firing rate curve is less for small neurons than large. It is concluded that this behavior is not a simple consequence of the cell geometry, but requires different time courses for a slow conductance across the cell membrane. This observation is consistent with the experimentally observed differences in time course of afterhyperpolarization between large and small cells (Eccles et al., 1958). The models are used to study input-output relations for motorneurons when the input is a steady conductance change on the cell membrane, possibly in conjunction with an injected current. Comparisons are drawn with the experimental observations of Kernell (1965a, 1965b) and Chaplain and Schaupp (1973). It is shown that the observations of Henneman et al. (1965a, 1965b) and Milner-Brown et al. (1973a, 1973b) on the order of recruitment of motorneurons under conditions of natural stimulation may be explained by the following version of the size principle: a given input to a pool of motorneurons causes equivalent conductance changes on each cell of the pool—here equivalent means the input is distributed to corresponding portions of the soma-dendritic tree and is of equal magnitude in mhos. Hypotheses are offered as to how this distribution of input may be accomplished in Nature.  相似文献   

12.
Data from one apparent crossover between S and H, two between PHI and HAL on one side and S on the other, and one between PHI on one side and HAL, S and H on the other, indicate a gene order in pigs of Phi-Hal-S-H-Pgd for genes for PHI, halothane sensitivity, inhibition of expression of A and O, H red blood cell antigens and 6-PGD types. Rasmusen et al. (1980) provided data for a gene order in pigs ofPhi-Hal-H-Pgd for genes for phosphohexose isomerase (PHI) isozyme variants, halothane sensitivity (HAL), H red cell antigens and 6-phosphogluconate dehydrogenase (6-PGD) variants, and suggested that there might be a locus for a gene for inhibition of expression of A and O separate from the locus for H. This is contrary to an earlier proposal by Rasmusen (1972) that the H-system genotype directly influences expression of A and O. Imlah (1980) suggested that the recessive gene for halothane sensitivity has a suppressant effect on the expression of A and O. Andresen (1981) proposed that the locus for inhibition of A and O (for which Rasmusen, 1964, proposed the symbol S) was between the loci for HAL and H types. Data presented in Table 1, which includes haplotypes for three recombinant offspring described by Rasmusen et al. (1980) (883-1, 233-3 and 3864-1) as well as one other recombinant (296-2) provide evidence for the gene order for five genes proposed by Andresen. Types for 6-PGD are listed for all pigs, although they do not provide evidence for gene order in these cases. Male 883-1 (Table 1, and Rasmusen et al., 1980, Table 5) provided the original evidence for recombination between S and H. His phenotype, as well as his genotype as revealed by progeny test (Rasmusen et al., 1980, Table 6) indicated that recombination had occurred between the genes for PHI, HAL and S and the gene for H type in his dam, so that the S locus mapped between H and the loci for the other three traits. The phenotype of one of his sons (233-3, Table 1, and Rasmusen et al., 1980, Table 6) indicated that there had been a recombination between genes for PHI and HAL types on one side and S and H types on the other, providing evidence that the S locus was separate from PHI and HAL as well as H. Another pig listed in Table 1,3864-1, was also described by Rasmusen et al. (1980, Table 9) as a recombinant. This pig provides evidence for recombination between PHI on one side and HAL, S and H on the other, establishing a gene order of Phi-Hal-S-H-Pgd. The last pig listed in Table 1,296-2, is a recombinant comparable to 233-3. The H type of his dam provides markers indicating the recombination was between PHI and HAL on one side and S and H on the other, although the unusual expression of HAL phenotype in both parents of 296-2 makes her haplotypes somewhat uncertain. (Recombination may have been between PHI and HAL rather than as indicated in Table 1.) In spite of incomplete penetrance for HAL (Ollivier et al., 1975; Smith & Bampton, 1977) which makes haplotypes for HAL questionable in some cases, the other genetic markers available are useful to show that recombination has taken place. Without considering the results of halothane testing, if the apparent recombinants are accepted as being as indicated, the order of the genes at the other four loci seems established. Alleles for S types appear to be separable by recombination from those for PHI and H, and the S locus appears to be between the loci for PHI and H. For the five loci, data obtained thus far are cohsistent with a gene order of Phi-Hal-S-H-Pgd.  相似文献   

13.
Im allgemeinen ist eine Mallophagengattung auf eine einzige Familie oder Ordnung ihrer Wirte beschränkt; seit N itzsch (1815) und K ellogg (1896) konnte diese Erscheinung immer wieder bestätigt werden. Damit ist auch naturgemäß die Verbreitung der Mallophagen identisch mit der ihrer Wirte; allerdings können extreme Klimate (s. E ichler , 1963, und N iethammer , 1962) das Vorkommen der Mallophagen im Gegensatz zu dem ihrer Wirte beschränken. Trotz dieser Ausnahmen ist es jedoch wegen des engen Wirt-Parasit-Verhältnis grundsätzlich möglich, mit Hilfe der Mallophagen-Verbreitung den Wirt betreffende, taxonomische, phylogenetische und zoogeographische Fragen zu erörtern. Wie erfolgreich diese Untersuchungsmethoden sind, zeigen etwa die Arbeiten von C lay (1961, 1964, 1966 a, b), E ichler (1963), E lbel & E merson (1959) und T immermann (1957, 1965).  相似文献   

14.
This minireview in memory of Daniel I. Arnon, pioneer in photosynthesis research, concerns properties of the first and still only known alternative photophosphorylation system, with respect to the primary phosphorylated end product formed. The alternative to adenosine triphosphate (ATP), inorganic pyrophosphate (PPi), was produced in light, in chromatophores from the photosynthetic bacterium Rhodospirillum rubrum, when no adenosine diphosphate (ADP) had been added to the reaction mixture (Baltscheffsky H et al. (1966) Science 153: 1120–1122). This production of PPi and its capability to drive energy requiring reactions depend on the activity of a membrane bound inorganic pyrophosphatase (PPase) (Baltscheffsky M et al. (1966) Brookhaven Symposia in Biology, No. 19, pp 246–253); (Baltscheffsky M (1967) Nature 216: 241–243), which pumps protons (Moyle J et al. (1972) FEBS Lett 23: 233–236). Both enzyme and substrate in the PPase (PPi synthase) are much less complex than in the case of the corresponding adenosine triphosphatase (ATPase, ATP synthase). Whereas an artificially induced proton gradient alone can drive the synthesis of PPi, both a proton gradient and a membrane potential are required for obtaining ATP. The photobacterial, integrally membrane bound PPi synthase shows immunological cross reaction with membrane bound PPases from plant vacuoles (Nore BF et al. (1991) Biochem Biophys Res Commun 181: 962–967). With antibodies against the purified PPi synthase clones of its gene have been obtained and are currently being sequenced. Further structural information about the PPi synthase may serve to elucidate also fundamental mechanisms of electron transport coupled phosphorylation. The existence of the PPi synthase is in line with the assumption that PPi may have preceded ATP as energy carrier between energy yielding and energy requiring reactions.  相似文献   

15.
The results of investigations done in 1965, 1966, and 1972 on the workload of motormen of high-speed trains operating on railroads with maximum speeds of 210 km/hr were compared in an attempt to discuss the physiological implications of the driving task. The driving time of a 515 km section was 4 hr in 1965 and was lowered to 3 hr 10 min since 1966 for the fastest super-express trains. The mean heart rate was maintained around 80 beats/min during the entire driving period in 1965, but declined gradually in 1966 or 1972. Although in 1966 the operations at constant high speed appeared to favor cerebral activities, drivers in the 1972 investigation not only showed lowered perceptual and choice reaction performances but also experienced significant increase in errors in detecting signal tones given as a subsidiary task. Polygraphic recordings in 1972 indicated that drivers sometimes fell into drowsing of short duration intermittently, accompanied by temporary drop in heart rate, absence of controller action, and increase of detection errors. These effects were dominant in periods after 90 min of driving. The need to reduce the monotomy effects during underloaded train driving is suggested.  相似文献   

16.
《Ibis》1967,109(2):290-291
E astwood , E. & R ider , G. C. 1966. Grouping of nocturnal migrants.
G yllin , R. 1965. (Some aspects of the inland wader migration over Sweden with special regard to the relationship between the resting and migrating numbers.)
H augh , J. R. & C ade , T. J. 1966. The spring hawk migration around the southern shore of Lake Ontario.
H ofslund , P. B. 1966. Hawk migration over the western tip of Lake Superior.
M erkel , F. W. & W iltschko , W. 1965. Nächtlide Zugunruhe und Zugorientierung bei Klein-vögeln.
W iltschko , W. & M erkel , F. W. 1965. Orientierung Zugunruhiger Rotkehlchen un Statischen Magnetfeld. Verhandlungen der Deutschen Zoologischen Gesellschaft in Jena 1965
Ö sterlöf , S. 1966. (The migration of the Goldcrest ( Regulus regulus ).)
S cott , R. E. 1965. Weights and measurements of migrant passerines, September 1962.
THIEDE, W. 1963–65. Die Verbreitung des Rotschenkels, Tringa totanus
8. Zoologischer Anzeiger  相似文献   

17.
18.
In the last few years special interest has been focused on enteric diseases localized to the lower alimentary tract, especially the ileum of weaned pigs. An increasing frequency of disorders of unknown aetiology described as regional ileitis (Emsbo 1951), necrotic enteritis (Jubb & Kennedy 1970), and intestinal adenomatosis (Rowland et al. 1973) has been reported. The changes include thickening of the ileal mucosa with hypertrophy of the muscular wall. The normal structure of villi is replaced by a proliferation of crypt cells. Necrosis of the mucosa and granulation-tissue proliferation in the submucosa occur in later stages. Regional ileitis in man (Crohn et al. 1932) which is described as a chronic enteric disease with granulomatous inflammatory changes localized to segments of the ileum is also attracting increasing attention in medical research (Liljefors 1972). The lesions are also found in the colon, and the presence of a transmissible agent involved in the aetiology of Crohn's disease has been discussed on the basis of animal experiments (Cave et al. 1973). The disease in pigs is accompanied by haematological changes, including decreased concentration of total serum protein, albumin, alkaline phosphatase, and zinc (Martinsson et al. 1974, 1976).  相似文献   

19.
Ecology of Phytoplankton of the Volta Lake   总被引:2,自引:2,他引:0  
S. Biswas 《Hydrobiologia》1972,39(2):277-288
Summary Regular limnological observations at the lower reaches of the Volta Lake revealed significant changes in the transparency, colour, total iron and dissolved oxygen from 1965 to 1966 but not from 1966 to 1967. These factors also showed correlations of such a significance that many of them could be estimated from a simple measurement of the transparency alone. The density of phytoplankton did not change significantly either from 1965 to 1966 or from 1966 to 1967. The chief constituents, however, passed through a series of changes from a green alga (Actinastrum) in early 1965, through the flagellates (Crytomonas and Peridinium) during 1965–1966, to the diatoms (Nitzschia and Synedra) during 1966–1967. The density of phytoplankton correlated significantly only with the dissolved oxygen from which it could be roughly estimated.
Résumé Les observations limnologiques régulières dans la partie Sud du Lac Volta révélaient des changements significatifs dans la transparence, la couleur, la quantité totale de fer et l'oxygène dissout pour la période de 1965 à 1966 mais rien de semblable pour celle de 1966 à 1967. Ces facteurs montraient aussi des corrélations si significatives que beaucoup d'entre eux pouvait être estimé à partie de la simple mensuration de la seule transparence. La densité de phytoplancton ne changeait pas de manière significative que ce soit de 1965 à 1966 ou de 1966 à 1967. Toutefois, les principaux constituants passaient par une série de changements allant des algues vertes (Actinatrum) au début de 1965, aux flagellates (Cryptomonas et Peridinium) de 1965 à 1966 puis aux diatomées (Nitzschia et Synedra) de 1966 à 1967. La densité de phytoplancton presentait une corrélation significative uniquement avec l'oxygène dissout duquel il pouvait être grossièrement estimé.
  相似文献   

20.
Infectious pancreatic necrosis (IPN) is a disease of salmonid fishes. It has been reported in many countries throughout the world (M’Gonigle 1940, Wood et al. 1955, Besse & Kinkelin 1965, Vestergård Jørgensen & Bregnballe 1969, Sano 1971, Ball et al 1971, Ljungberg & Vestergård Jørgensen 1972, Schlotfeldt et al. 1975). Outbreaks of the disease can cause serious losses in populations of hatchery reared salmonids, the mortality rate varying between 10 and 90 % (Vestergård Jørgensen & Kehlet 1971). There are at least four different serotypes of the virus distinguished by neutralization tests (Wolf et al. 1968). Twenty-five isolates of IPN virus in Denmark proved to represent only two serotypes (Sp and Ab) (Vestergård Jørgensen & Kehlet). The present paper reports the first isolation of IPN virus from the stock at a fish farm in Norway.  相似文献   

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