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121.
The polariscopic examination of isolated shoulder joint capsules shows that the entire capsule does not have a homogeneous collagen structure. Most of the capsule is characterized by regular collagen fibers which cross at an obtuse angle in the area of the musculus supraspinatus and at an acute angle in the area of the m. infraspinatus. The density of the collagen network increases from the medial to the lateral part. Deviating from this basic pattern of the joint capsule, there is a different collagen texture in the area between the m. supraspinatus and the m. subscapularis. This texture has dissociated, rarefied and irregular collagen fibers. This means that the area--in comparison with the remainder of the capsule--is characterized not only by missing reinforcing ligaments but also by a deviating pattern of the collagen fibers. This different collagen structure is already existent in the fetus. 相似文献
122.
Michael Lippert Karl Steiner Hans-Dieter Payer Sabina Simons Christian Langebartels Heinrich Sandermann Jr. 《Trees - Structure and Function》1996,10(4):268-275
An exposure — response study with proportionalto-ambient ozone levels was conducted in closed chambers on 3-year-old European beech (Fagus sylvatica L.) of montane origin. The fumigation started in April 1990 and lasted for a single growing season. Climate data and ozone concentrations monitored at an experimental station of the Institute for Applied Plant Biology, Schönenbuch, Switzerland were simulated in the exposure chambers 12 days later (1*O3). To test exposure-response relations three additional treatments were applied, subambient (0.2*O3) and two proportionally increased ozone treatments (1.5*O3 and 2*O3). The photosynthetic behaviour of the trees in August revealed the light reactions to be less affected than parameters which are related to the dark reactions of photosynthesis. Assimilation (A350), apparent carboxylation efficiency (CE), and maximum photosynthetic capacity (A2500) were reduced with increasing ozone concentration. For the ozone response of CE and A2500 Critical Levels were calculated. 相似文献
123.
Summary In the young part of the stem of Polytrichum commune the protoplasts of the two types of conducting cells, the leptoids and parenchyma cells, are nearly identically equipped with cell organelles and cytoplasmic structures. Both types contain a nucleus, chloroplasts, mitochondria, and dictyosomes. The endoplasmic reticulum builds characteristic cisterns in form of hollow cylinders extending from one end wall to the other. The cisterns are connected with many plasmodesmata, which occur only in the end walls. Leptoids have oblique end walls with 16 to 20 plasmodesmata per m2, and parenchyma cells show cross walls perpendicular to the axis with 9 to 12 plasmodesmata per m2.Since the leptoids are supposed to be the pathways for the longitudinal transport of assimilates (Eschrich and Steiner, 1967, 1968), it is of interest that early in their development these elements undergo a change in their protoplasmatic structure. Two to 3 cm below the apical cell the protoplasts degenerate and show lysosome-like structures. The endoplasmic reticulum and other structures are deformed or dissolved; the plasmodesmata are constricted by callose deposits. At the same level the parenchyma cells still retain the original structure of their protoplasts.Thus, assimilates moving upward in one row of leptoids may penetrate the whole lumen of the leptoids at lower levels, but they are restricted to the cisterns of the endoplasmic reticulum at higher levels of the stem. 相似文献
124.
Stefenon Valdir Marcos Ree Joseph Francis Pinheiro Marcos Vinicius Marques Goeten Daniela Steiner Neusa Guerra Miguel Pedro 《Plant Cell, Tissue and Organ Culture》2020,142(2):241-251
Plant Cell, Tissue and Organ Culture (PCTOC) - Mambalgin-1 is a peptide that acts as a potent analgesic through inhibiting acid-sensing ion channels (ASIC) in nerve cells. Research has shown that... 相似文献
125.
Molecular mapping of QTLs for Fusarium head blight resistance in spring wheat. II. Resistance to fungal penetration and spread 总被引:3,自引:0,他引:3
Buerstmayr H Steiner B Hartl L Griesser M Angerer N Lengauer D Miedaner T Schneider B Lemmens M 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2003,107(3):503-508
Fusarium head blight (FHB, scab) causes severe yield and quality losses, but the most serious concern is the mycotoxin contamination of cereal food and feed. The cultivation of resistant varieties may contribute to integrated control of this fungal disease. Breeding for FHB resistance by conventional selection is feasible, but tedious and expensive. The aim of this work was to detect QTLs for combined type I and type II resistance against FHB and estimate their effects in comparison to the QTLs identified previously for type II resistance. A population of 364, F1 derived doubled-haploid (DH) lines from the cross 'CM-82036' (resistant)/'Remus' (susceptible) was evaluated for components of FHB resistance during 2 years under field conditions. Plants were inoculated at anthesis with a conidial suspension of Fusarium graminearum or Fusarium culmorum. The crop was kept wet for 20 h after inoculation by mist-irrigation. Disease severity was assessed by visual scoring. Initial QTL analysis was performed on 239 randomly chosen DH lines and extended to 361 lines for putative QTL regions. Different marker types were applied, with an emphasis on PCR markers. Analysis of variance, as well as simple and composite interval mapping, revealed that two genomic regions were significantly associated with FHB resistance. The two QTLs on chromosomes 3B (Qfhs.ndsu-3BS) and 5A (Qfhs.ifa-5A) explained 29 and 20% of the phenotypic variance, respectively, for visual FHB severity. Qfhs.ndsu-3BS appeared to be associated mainly with resistance to fungal spread, and Qfhs.ifa-5A primarily with resistance to fungal penetration. Both QTL regions were tagged with flanking SSR markers. These results indicate that FHB resistance was under the control of two major QTLs operating together with unknown numbers of minor genes. Marker-assisted selection for these two major QTLs appears feasible and should accelerate the development of resistant and locally adapted wheat cultivars. 相似文献
126.
Methyl 2,3-O-isopropylidene-alpha-D-mannofuranosidurononitrile [alternative name: methyl (5R)-5-C-cyano-2,3-O-isopropylidene-alpha-D-lyxofuranoside] (2), methyl 2,3-O-isopropylidene-alpha-D-mannofuranosiduronamide [methyl (5S)-5-C-carbamoyl-2,3-O-isopropylidene-alpha-D-lyxofuranoside; methyl (5S)-2,3-O-isopropylidene-alpha-D-lyxo-hexofuranosiduronamide] (3), methyl 2,3-O-isopropylidene-alpha-D-mannofuranosiduronic acid [methyl (5S)-2,3-O-isopropylidene-alpha-D-lyxo-hexofuranosiduronic acid] (4), methyl 5-deoxy-2,3-O-isopropylidene-5-ureido-beta-L-gulofuranosiduronamide [methyl (5R)-5-deoxy-2,3-O-isopropylidene-5-ureido-alpha-D-lyxo-hexofuranosiduronamide (5), and (4S,5S,6R)-5,6-dihydro-6-hydroxy-4,5-isopropylidenedioxy-4H-pyrido[2,1-e]imidazolidine-2',4'-dione [IUPAC name: (3aS,4R,8aS)-4-hydroxy-2,2-dimethyl-3a,8a-dihydro-4H-1,3-dioxa-4a,6-diaza-s-indacene-5,7-dione] (6), instead of the expected hydantoin derivative, were obtained from the Bucherer-Bergs reaction of methyl 2,3-O-isopropylidene-alpha-D-lyxo-pentodialdo-1,4-furanoside (1). The structure of 6 was deduced from NMR and mass spectral data and confirmed by X-ray crystallography. The configuration at C-5 in 2-5 was confirmed by establishing the 5S configuration of 3 by X-ray crystallography. Conformations of the six- and five-membered rings in 3 and 6 are also discussed. 相似文献
127.
Robert F. Steiner Mahnaz Motevalli-Alibadi 《Archives of biochemistry and biophysics》1984,234(2):522-530
The average separation of the phenolic groups of tyrosine-99 and tyrosine-138 has been measured by radiationless energy transfer between each tyrosine and the nitro derivative of the second tyrosine. A separation of 16.7 ± 0.7 Å was found in the absence of Ca2+ and 15.5 ± 0.7 Å in the presence of Ca2+. 相似文献
128.
129.
A genetic map of melon highly enriched with fruit quality QTLs and EST markers, including sugar and carotenoid metabolism genes 总被引:4,自引:0,他引:4
R. Harel-Beja G. Tzuri V. Portnoy M. Lotan-Pompan S. Lev S. Cohen N. Dai L. Yeselson A. Meir S. E. Libhaber E. Avisar T. Melame P. van Koert H. Verbakel R. Hofstede H. Volpin M. Oliver A. Fougedoire C. Stalh J. Fauve B. Copes Z. Fei J. Giovannoni N. Ori E. Lewinsohn A. Sherman J. Burger Y. Tadmor A. A. Schaffer N. Katzir 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,121(3):511-533
A genetic map of melon enriched for fruit traits was constructed, using a recombinant inbred (RI) population developed from a cross between representatives of the two subspecies of Cucumis melo L.: PI 414723 (subspecies agrestis) and ‘Dulce’ (subspecies melo). Phenotyping of 99 RI lines was conducted over three seasons in two locations in Israel and the US. The map includes 668 DNA markers (386 SSRs, 76 SNPs, six INDELs and 200 AFLPs), of which 160 were newly developed from fruit ESTs. These ESTs include candidate genes encoding for enzymes of sugar and carotenoid metabolic pathways that were cloned from melon cDNA or identified through mining of the International Cucurbit Genomics Initiative database (http://www.icugi.org/). The map covers 1,222 cM with an average of 2.672 cM between markers. In addition, a skeleton physical map was initiated and 29 melon BACs harboring fruit ESTs were localized to the 12 linkage groups of the map. Altogether, 44 fruit QTLs were identified: 25 confirming QTLs described using other populations and 19 newly described QTLs. The map includes QTLs for fruit sugar content, particularly sucrose, the major sugar affecting sweetness in melon fruit. Six QTLs interacting in an additive manner account for nearly all the difference in sugar content between the two genotypes. Three QTLs for fruit flesh color and carotenoid content were identified. Interestingly, no clear colocalization of QTLs for either sugar or carotenoid content was observed with over 40 genes encoding for enzymes involved in their metabolism. The RI population described here provides a useful resource for further genomics and metabolomics studies in melon, as well as useful markers for breeding for fruit quality. 相似文献
130.