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1.
Summary By using oligonucleotide hybridization, restriction endonuclease analysis and direct sequencing of amplified genomic DNA, we have been able to characterize 18 different mutations in the -globin genes of 161 thalassemia homozygotes and 107 -thalassemia heterozygotes from Turkey (429 -thalassemia chromosomes). Previous studies dealing with -thalassemia in Mediterranean countries have shown that, in most Mediterranean populations, only a few mutations are prevalent. In contrast, -thalassemia in Turkey does not seem to be associated with a few predominant mutations. The six most frequent alleles, IVS-I-110 (GA), IVS-I-6(TC), FSC-8 (-AA), IVS-I-1(GA), -30(TA) and FSC-5 (CT), account for only 69.3% of the disease genes; indeed, all 26 mutations assayed represent 85.8% of the disease genes, confirming the considerable molecular heterogeneity of -thalassemia among Turks, and indicating the possible presence of rare, previously undefined, mutations in the population. Two mutations observed in this study, IVS-I-116 (TG) and Cd44(-C), have not been reported in the Turkish population to date. Since preventive medical services, such as genetic counseling and prenatal diagnosis, are greatly improved by detailed knowledge of the molecular pathology of thalassemia, we strongly believe that the presented data will facilitate the intended establishment of a prenatal diagnosis center, based on DNA analysis, in Turkey.  相似文献   

2.
We have studied the mechanism of Ca current inactivation in the -cell line HIT-T15 by conventional and perforated patch recording techniques, using two pulse voltage protocols and a combination of current and tail current measurements. In 5 mM Ca, from a holding potential of - 80 mV, the maximum current showed a complex time course of inactivation: a relatively fast, double exponential inactivation (h1 12 ms and h2 60 ms) and a very slowly inactivating component ( > 1 s). The faster component (h1) was due to the voltage-dependent inactivation of a low-threshold-activated (LVA), T-type current, which deactivates more slowly ( 3–5 ms) than the other components ( 0.2–0.3 ms). The intermediate component (h2) was due to the Ca-dependent inactivation of a portion of the high-threshold-activated (HVA) current. A saturating dose of the dihydropyridine (DHP) nifedipine (10 M) did not affect the LVA current, but inhibited by 68 ± 5% the transient, Ca-sensitive portion of the HVA current and by 33 ± 12% the long lasting component. We suggest that three components of the calcium current can be resolved in HIT cells and the main target of DHPs is a HVA current, which inactivates faster than the DHP-resistant HVA component and does so primarily through calcium influx. Correspondence to: C. Marchetti  相似文献   

3.
Zusammenfassung Im sessilen Bulbus olfactorius von Teleosteern werden große Nervenzell-Somata als bulbäre Riesenzellen beschrieben. Sie treten bei Arten mit einem gestielten Bulbus nicht auf. Ihre Anordnung geht parallel mit dem bulbären Verlauf des Nervus terminalis. Holmgrens Kaudale Zellgruppe bzw. das Kerngebiet des Nervus terminalis (Scharrer) ist eine häufig anzutreffende Gruppierung dieser Zellen am caudalen Bulbusende. Es wird die Möglichkeit erörtert, ob die bulbären Riesenzellen nicht den Ganglienzellen des Nervus terminalis verwandte Strukturen darstellen.
Giant cells in the olfactory bulb of teleostean fishes
Summary Large nerve cell somata are described as bulbar giant cells in the sessile olfactory bulb of teleostean fishes. They are not found in species with a stalked olfactory bulb. They are arranged along the bulbar course of the nervus terminalis. In the Kaudale Zellgruppe of Holmgren and the Kerngebiet des Nervus terminals of Scharrer a greater part of these giant cells lie at the caudal end of the bulb. It is discussed if these cells are related to the ganglion cells of the nervus terminalis.
  相似文献   

4.
Summary Dark grown seedlings ofLactuca sativa L. var. Grand Rapids (tip burn resistant strain) do not form an appreciable plumular hook. But a normal plumular hook, as is formed e. g. byPhaseolus vulgaris in complete darkness, can be induced by red light. It has been shown in this paper that the formation of the plumular hook in lettuce seedlings is controlled exclusively by the reversible red far-red reaction system (low energy reaction).The hook which has been closed by red radiation can be reopened by light. In this respect only blue and far-red radiation are effective. The hook can only be reopened if blue or far-red are applied with rather high irradiances over a relatively long time period (high energy reaction). The action spectrum and the kinetics of this high energy reaction show that this photoreaction is identical with the so called blue, far-red reaction system which we could demonstrate during recent years to be involved in the photomorphogenesis of the mustard seedling (Sinapis alba L.) and which apparently is also involved in many other photomorphogenic responses (cf.Hendricks et al. 1960). In mustard the low and the high energy reactions always function in a synergistic manner, in lettuce the opposite is true: The closing of the plumular hook is controlled by the reversible red, far-red system, the reopening of the hook is controlled by the blue, far-red system. In this way the two systems can be more clearly separated and characterized physiologically.

Mit 12 Textabbildungen  相似文献   

5.
On age morphological changes of males of Chydoridae (Cladocera)   总被引:2,自引:2,他引:0  
N. N. Smirnov 《Hydrobiologia》1967,30(3-4):555-571
Summary Young and adult males of 11 species of Chydoridae are studied, their figures being published here (fig. 1–15). The necessity is stressed to distinguish young forms of males and gynandromorphic individuals.Pleuroxus balatonicus is considered to be described from the population ofPleuroxus unicatus having under Balaton Lake conditions retarded transformation of young males into adult form, and accordingly having unusually numerous young males. \qO\qs\qn\qo\qv\qn\qy\ye \qr\ye\qz\qu\ql\Qj\qt\qa\qt\qy 11 (. 1–15). . , Pleuroxus uncinatus , Pleuroxus balatonicus.  相似文献   

6.
Summary Size and shape of mitochondrial DNA molecules of Schizosaccharomyces pombe were analyzed by electron microscopy. Besides numerous linear molecules, circular molecules ranging from 0.83 m to 12.81 m were found. Depending on the method of preparation, both closed and open circular molecules were found. Most of the circular molecules could be assigned to five major size classes of 0.83±0.05 m, 1.7±0.05 m, 4.74±0.04 m, 5.74±0.04 m, and 8.32±0.07 m. Possible explanations for the different size classes of mitochondrial DNA molecules are discussed.  相似文献   

7.
Feulgen and silver-stained karyotypes and meiosis of two triploid viviparous onion forms (Allium cepa var.viviparum), the Croatian Ljutika and the Indian Pran, were comparatively analyzed. The results of chromosome measurements show that Ljutika and Pran are karyologically not identical, although significant similarities were found in the morphology of their chromosomes. Five geographically distant clones of Ljutika showed good agreement in the number and gross morphology of the chromosomes and in the number and position of NORs and interphase nucleoli. Heterotrivalents were predominant in meiosis of Ljutika but a relatively high frequency of higher multivalents together with univalents and bivalents were also observed. The relationship between Ljutika and Pran and their possible origin are discussed.  相似文献   

8.
    
Summary 1. Aerial chases of a female duck by a number of (Reihen) include three different forms of chasings: a) chases in connection with swimming courtship (Gesellschaftsspiel); b) territorial chases performed by a which is driving away a of a pair that had entered the territory of the former; c) chases of a in brooding mood by a number of intending to copulate.2. Aerial chases of type a) are part of the courtship, they are courtship flights. They are preceded and often followed by swimming courtship and they are characterized by the birds uttering their courtship calls. They may be observed from late August to the beginning of May.3. Chases of type c) are characterized by the female's call and gesture of repulsion. It only occurs when the female is laying or brooding. The periods of chases of type a) and c) overlap, which may explain the controversy betweenGeyr vonSchweppenburg andChristoleit.4. The Red-crested Pochard- has a special gliding performance during its courtship flight.  相似文献   

9.
Zusammenfassung Ein hochgeordnetes System tubulärer Strukturen wurde als bisher unbekannter Plasmaeinschluß in den Siebelementen von Dioscorea reticulata beschrieben. 250 Å weite, kontrastreiche Tubuli ordnen sich in hexagonal dichtester Packung zu 0,2 bis 1,3 großen Körpern an. Die einzelnen Tubuli sind helixähnlich gewunden und geben dem Plasmaeinschluß eine den Heitz-Leyon-Kristallen der Plastiden von Chlorophytum ähnliche Gestalt. Herkunft und Bedeutung dieser Gebilde sind noch weitgehend unbekannt.
On the fine structure of a lattice-like body in the sieve elements of Dioscorea reticulata
Summary In the parietal protoplast of differentiated sieve elements of Dioscorea reticulata an up to now unknown lattice-like body has been described in detail. Many 250 Å wide tubules combine to form very regularly composed bodies, which are about 0.2 to 1.3 large. Each tubule is twined like a helix and is spaced equidistantly from the adjoining ones, the interval being 450 to 500 Å. On the whole the lattice-like bodies of Dioscorea largely resemble the so-called Heitz-Leyon-crystals of young plastids.


Mit 2 Textabbildungen  相似文献   

10.
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   

11.
Four glycosidases were analyzed in 10 mm apical segments prepared from growing roots (15 mm) of Zea mays L. The pH optima were found to be 5.8 for -glucosidase, 4.4 for -galactosidase, 6.4 for -glucosidase and 6.0 for -galactosidase. The -glucosidase showed 4-fold higher activity than the -galactosidase. The distribution of the -glucosidase activity was signifcantly different from that of the -galactosidase, -glucosidase and -galactosidase.Abbreviations -Glu -glucosidase - -Gal -galactosidase - -Glu -glucosidase - -Gal -galactosidase  相似文献   

12.
EF-1a binds aminoacyl-tRNA to the ribosome with the hydrolysis of GTP; the complex facilitates the exchange of GDP for GTP to initiate another round of elongation. To examine the subunit structure of EF-1 and phosphorylation by protein kinase CKII, recombinant , , and subunits from rabbit were expressed in E. coli and the subunits were reconstituted into partial and complete complexes and analyzed by gel filtration. To determine the availability of the and subunits for phosphorylation by CKII, the subunits and the reconstituted complexes were examined as substrates for CKII. Formation of the nucleotide exchange complex increased the rate of phosphorylation of the subunit and reduced the Km, while addition of to or the complex inhibited phosphorylation by CKII. However, a had little effect on phosphorylation of . Thus, the and subunits in EF-1 were differentially phosphorylated by CKII, in that phosphorylation of was altered by association with other subunits, while the site on was always available for phosphorylation by CKII. From the availability of the subunits for phosphorylation by CKII and the composition of the reconstituted partial and complete complexes, a model for the subunit structure of EF-1 consisting of (22)2 is proposed and discussed.  相似文献   

13.
The preparation of benzyl 2,3,6,2,6-penta-O-benzyl--d-lactoside, which is a key intermediate for chemical synthesis of oligosaccharide components of glycosphingolipids, was achieved by an improved method. The 3-O-p-methoxybenzyl and 3-O-methyl derivatives were prepared from benzyl 2,3,6,2,6-penta-O-benzyl--d-lactoside through stannylation. By using benzyl -d-lactoside as starting material, benzyl 3-O-methyl-, 3-O-benzyl- and 3-O-p-methoxybenzyl--d-lactoside were regioselectively synthesized using the same procedure.  相似文献   

14.
R. Wiermann 《Planta》1970,95(2):133-145
Summary The synthesis and accumulation of several phenylpropanes in the anther content (pollen+tapetum fraction) during microsporogenesis has been investigated by chromatographic techniques in Narcissus pseudonarcissus, Lilium candidum, and in the Darwin tulip Apeldoorn.In these species, the pigmentation process is initiated by the synthesis of several cinnamic acid derivates (mainly derivates of ferulic acid) during meiosis II. In Narcissus, and intense synthesis of kaempferol glycosides takes place during the separation of the tetrad which follows immediately upon its formation. In Tulipa and Lilium, however, chalcones are synthesized in an intermediate phase before flavonols and anthocyanins (in Tulipa) are produced in significant amounts.In Tulipa, the investigations revealed the following sequence in the pigmentation process: cinnamic acid derivatives-chalcone-flavonols-anthocyanins. The sequence is discussed in relation to flavonoid biosynthesis. Because of biogenetic considerations a special emphasis is laid on the chalcone stage. Chromatographic and spectroscopic data show that the isomerization product of the chalcone is eriodictyol. Accordingly, this chalcone must be 2,3,4,4,6-pentahydroxychalcone. Other chalcones could not be identified.During anthesis the following aglycones are accumulated in the pollen of Tulipa cv. Apeldoorn: ferulic acid, p-coumaric acid, kaempferol, quercetin, isorhamnetin, delphinidin, and small traces of the pentahydroxy-chalcone, which is the main pigment in the intermediate stages of microsporogenesis.On the basis of histochemical findings, it is suggested that at least the final steps of synthesis leading to flavonol and anthocyanidin glycosides take place on the pollen wall in the loculus of the anthers, that is, in the extracellular space.

Untersuchungen zum Phenylpropanstoffwechsel des Pollens IV.  相似文献   

15.
Summary A series of man-Chinese hamster and man-mouse somatic cell hybrids was investigated to study the localization of the genes coding for the human lysosomal enzyme -galactosidase (EC 3.2.1.23) and for its protective protein. Using a monoclonal antibody, raised against human placental -galactosidase, it was observed that the structural locus for the -galactosidase polypeptide is located on chromosome 3. The nature of the involvement of chromosome 22 in the expression of human -galactosidase was elucidated by metabolic labelling of the hybrids with radioactive amino acids, immunoprecipitation with monoclonal and polyclonal antibodies against -galactosidase, followed by analysis via gel electrophoresis and fluorography.The data show that the presence of chromosome 22 coincides with the presence of a 32 kd protein. This polypeptide, the protective protein was previously shown to be intimately associated with human -galactosidase. In addition, the protective protein was found to be essential for the in vivo stability of -galactosidase by aggregating -galactosidase monomers into high molecular weight multimes. Both chromosome 3 and 22 are therefore necessary to obtain normal levels og -galactosidase activity in human cells.  相似文献   

16.
Summary The inheritance of resistance to whitebacked planthopper Sogatella furcifera (Horvath) was studied in 21 rice varieties. Reactions of F1; F2 and F3 progenies of the crosses of 21 resistant varieties with the susceptible variety TN 1 revealed that a single dominant gene governs resistance in Mushkan 41, Santhi, Siahnakidar 195, SM2-34, Tirisurkh 251, Zirijowaian 245, 18, 24A, 39, 76 S, 78, 180, 213 B, 267, 293, CI 6037-4, NP97, S39 JKW and Bansphul. In varieties 65 and 274 A, resistance is governed by one dominant and one recessive gene which segregate independently of each other. Tests for allelism with the Wbph 1 gene originally identified in N 22 revealed that the dominant gene present in all the test varieties is the same as Wbph 1. Further studies are required to determine the allelic relationships of the recessive gene found in varieties 65 and 274 A.  相似文献   

17.
The properties of the -2-l-fucosyltransferases in submaxillary gland preparations from blood group ABH secrefors and non-secretors were compared. The level of activity in the non-secretor gland homogenates amounted to about 5% only of that found in the secretor gland preparations. The enzymes from the two sources differed in solubility properties, charge and affinities for donor and acceptor substrates. The enzyme from secretor glands showed a preference for acceptors with Type 1 [d-galactosyl(1–3)-N-acetyl-d-glucosamine] structures whereas the enzyme from non-secretor glands had a preference for Type 2 [d-galactosyl(1–4)-N-acetyl-d-glucosamine] structures.These results demonstrate that expression of the secretor gene (Se) is associated with a molecular form of the -2-l-fucosyltransferase that is different from the species present in the same tissue when theSe gene is not expressed.  相似文献   

18.
Imaginal disks and the gonads of Ch. thummi have been used to obtain clear criteria for the determination of the developmental stage of 4th instar larvae. The imaginal anlagen are growing continuously and the established developmental phases are representing equal intervals of time.

Mit Unterstiitzung der Deutschen Forschungsgemeinschaft.

Die Arbeit wurde Herrn Prof. Dr. W. Kuhl zum 75. Geburtstag gewidmet.  相似文献   

19.
Wu AM 《Neurochemical research》2002,27(7-8):593-600
Glycosphingolipids (GSLs) contain many carbohydrate epitopes or crypto-glycotopes for Gal and GalNAc reactive lectins. Many of them are in the nervous system and function as important receptors in various life processes. During the past two decades, 11 mammalian structural units have been used to express the binding domain of applied lectins. They are: F, GalNAc1 3GalNAc; A, GalNAc1 3Gal; T, Gal1 3GalNAc; I, Gal1 3GlcNAc; II, Gal1 4GlcNAc; B, Gal1 3Gal; E, Gal1 4Gal; L, Gal1 4Glc; P, GalNAc1 3Gal; S, GalNAc1 4Gal, and Tn, GalNAc1 Ser(Thr). Although 10 of them occur in GSLs, only 3 (L , S , and T ) are found in human brain, and 2 (L and II ) are present in the inner structures of human blood group active GSLs. In the families of gangliosides, L and II represent 55% of the total structural units, while the other three units (T , P , and S ) constitute the rest. To facilitate the selection of lectins that could serve as structural probes, the carbohydrate binding specificities of Gal/GalNAc reactive lectins have been classified according to their highest affinity for the structural units and their binding properties expressed by decreasing order of reactivity. Hence, the binding relation between GSLs and Gal/GalNAc specific lectins can be established.  相似文献   

20.
Zeins from Zea mays L cv. Maya and coixins from Coix lacryma-jobi L. cv. Adlay were fractionated to obtain -, -, and -zein and -, -, and -coixin. The -coixins were composed of 4 polypeptide classes of 27 kDa (C1), 25 kDa (C2), 17 kDa (C4) and 15 kDa (C5) with solubility properties very similar to those of the 22 kDa and 19 kDa -zeins. Like the -zeins, the C1 and C2 -coixins corresponded to 80% of total Coix prolamins. The fraction corresponding to -coixin contained only one protein band of 22 kDa (C3). This coixin fraction has solubility properties similar to those of -zein and represents 15% of the total coixin. The -zein fraction was composed of a major 17 kDa protein band, while the -coixin fraction consisted of a mixture of - and -coixins.Polyclonal antibodies raised against C1 recognized C1 and C2 and cross-reacted strongly with the 22 kDa -zein, as did C4 and C5 antisera. The antiserum against -coixin showed strong cross-reaction with -zein. The homology between coixins and zeins was further investigated by using Southern hybridization analyses. The genomic DNA of maize and Coix were digested with several restriction enzymes and probed with cDNA clones representing 19 and 22 kDa -zeins as well as the 28 and 16 kDa -zeins. The Coix genome showed complex cross-hybridization sequences with the 22 kDa -zein cDNA, while no cross-hybridization was observed with the 19 kDa cDNA clone. The cDNA clone representing the 28 kDa -zein cross-hybridized with only one band of Coix genomic DNA, in contrast to the three bands observed in maize. This same Coix sequence also cross-hybridized with the cDNA clone representing the 16 kDa -zein. The relevance of these findings are discussed in the context of the origin of zein and coixin genes.  相似文献   

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