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1.
The morphology and innervation of the six oculomotor muscles in the gobiid fishTridentiger trigonocephalus are described. Every rectus muscle is composed of two types of muscle fibres. Muscles attach onto the cartilaginous or fibrous
sclerotica. Oblique muscles attach onto the ethmoidal plate; recti muscles attach onto the parasphenoid or a thick fibrous
membrane. There is no myodome. The common oculomotor nerve is composed of four bundles, the trochlear and the externus of
two. The two kinds of fibres of the lateral rectus and the two distinct bundles of the nerve VI suggest a possible homology
between this muscle in fishes and the lateral rectus+retractor bulbi in mammals. 相似文献
2.
The aim of this investigation was to evaluate the semen quality traits of purebred male rabbits and their crosses under subtropical Egyptian conditions. A full 3 x 3 diallel crossing was performed for producing the first generation progeny of New Zealand White (N), Flander (F) and Rex (R) breeds. The highest ejaculate volume (p< 0.05) and percentage of live sperms (p<0.01) with the lowest percentage of sperm cell morphological abnormalities (p<0.05) had been recorded in the NF bucks. Moreover, they possessed positive estimates of direct heterosis for ejaculate volume, mass motility (Mm), individual motility (Im) and sperm cell concentration (SCC). On the contrary, pH had negative estimates of direct heterosis in all crosses and their reciprocal. Semen pH was negatively correlated with SCC (r = -0.18), Mm (r = -0.13) and Im (r = -0.23). In conclusion, the superiority of crossbreeding was particularly obvious in the New Zealand White x Flander males, which cumulated heterosis and favorable maternal effects of the Flander dams. 相似文献
3.
Mingyue Wang Pranab K Mukherjee Jyotsna Chandra Ali Abdul Lattif Thomas S McCormick Mahmoud A Ghannoum 《BMC microbiology》2008,8(1):31
Background
We have previously shown that supernatant from Candida albicans (CA) culture contains a Secretory Interleukin (IL)-12 Inhibitory Factor (CA-SIIF), which inhibits IL-12 production by human monocytes. However, the effect of CA-SIIF on secretion of other cytokines by monocytes is unknown, and detailed characterization of this factor has not been performed. 相似文献4.
5.
Activity of phosphate-dissolving bacteria in Egyptian soils 总被引:1,自引:0,他引:1
S. M. Taha S. A. Z. Mahmoud A. Halim El-Damaty A. M. Abd El-Hafez 《Plant and Soil》1969,31(1):149-160
6.
A variety of morphological changes in the basement membrane (BM) are known to occur in inflammatory diseases. Modifications of the BM can be associated with significant changes in protein content. Candida albicans (C. albicans) is normally a commensal organism and is a member of the natural flora of a large number of healthy individuals. However, under certain conditions, C. albicans can invade host tissues, causing inflammation and tissue damage. The aim of this study was to investigate the effect of C. albicans on the expression and production of structural (laminin-5 and type IV collagen) and inflammatory [matrix metalloproteinases (MMPs) and their inhibitors] proteins by human oral epithelial cells. Using engineered normal human oral mucosa infected with 10(5) C. albicans/cm2 for different periods of time, we were able to demonstrate that this yeast promotes significant laminin-5 and type IV collagen gene activation and protein secretion. These effects were accompanied by MMP-2 and MMP-9 gene activation. Interestingly, only the levels of active MMP-9 rose. The increase in MMP levels was paralleled by a decrease in the secretion of type 2 matrix metalloproteinase tissue inhibitors (TIMP-2). Our results demonstrated that C. albicans has a significant effect on tissue structure through BM protein and MMP modulation. This might help C. albicans overcome the mechanical and biological defenses of the tissue and allow it to disseminate, causing severe infections. If C. albicans uses MMPs (mainly MMP-9) to disseminate, inhibition of this protease could be of interest in treating a variety of inflammatory disorders, including oral candidiasis. 相似文献
7.
Abdel-Halim Mahmoud Mohammed El-Sayed Hans Jürgen Rehm 《Applied microbiology and biotechnology》1987,26(3):211-214
Summary The growth rates of immobilized Penicillium chrysogenum strains are important in their application to semicontinuous penicillin production. Immobilized P. chrysogenum strains produced about 10–15% less biomass but about 1–2 times more penicillin than free suspended mycelia.In a chemically defined medium an industrial P. chrysogenum strain, S1, produced about 10–12 times more penicillin than strain ATCC 12690. In a complex medium the immobilized P. chrysogenum S1 produced about 12% penicillin more than in shaken cultures. In bubble column fermentations, penicillin production was 163% higher in the complex medium than in the chemically defined medium. 相似文献
8.
The kinetics of the oxidation of CoII(EDTA)2− by IO4− were studied in various ethanol + water mixtures covering the range 7.9 to 58.0 wt% ethanol, at five different temperatures in the range 15–35 °C. The effect of solvent on the rate and mechanism of the reaction was investigated. An inner-sphere mechanism for the reaction was proposed and supported by the calculated activation parameters. 相似文献
9.
N G Fossett P Arbour-Reily G Kilroy M McDaniel J Mahmoud A B Tucker S H Chang W R Lee 《Mutation research》1990,231(1):73-85
N-Ethyl-N-nitrosourea (ENU) was used to induce mutations in the Drosophila melanogaster, alcohol dehydrogenase (Adh) gene. Flies were treated with ENU and mated to homozygous intragenic Adh null mutants; Adh null mutations were selected by exposure of the F1 generation to 1-penten-3-ol. Fourteen Adh null mutations were recovered which included 11 from spermatozoa, 2 from oocytes and 1 from a premeiotic spermatocyte. 2 mutations from spermatozoa and 1 of the mutations from oocytes were multilocus deficiencies which included the Adh locus as determined by complementation tests. The remaining 11 intragenic Adh null mutations were sequenced using the Sanger dideoxy method. One Adh null mutation induced in an oocyte was an AT to TA transversion and the mutation induced in a premeiotic spermatocyte was a GC to AT transition, both of which resulted in a single amino acid substitution. The 11 null mutations induced in spermatozoa were a data set in which both the dose of ENU and the treated germ-cell stage were held constant; therefore, only these 11 mutations were used to calculate the mutation frequency and compare the mutations at the Adh locus with those recovered in other studies. The dose of ENU induced a sex-linked recessive lethal frequency approximately 300 times that of the spontaneous frequency; therefore, these mutations were assumed to have been induced by ENU. 2 of the 11 mutations induced in spermatozoa were multilocus deficiencies and 9 were intragenic mutations. 7 of the 9 intragenic mutations were GC to AT transitions which resulted in 5 single amino acid substitutions, 1 premature translation termination codon, and 1 splice site mutation.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
10.
J R Paulson P W Mesner J J Delrow N N Mahmoud W A Ciesielski 《Analytical biochemistry》1992,203(2):227-234
A new method is described for analysis of histone H1 and other basic proteins by cationic disc electrophoresis in polyacrylamide gels at neutral pH. The multiphasic buffer (disc) system uses Na+ as leading ion, L-histidine as trailing ion, and Hepes as buffering counterion. These "Hepes/histidine gels" have three advantages over conventional acid-urea gels for studies of H1 phosphorylation and dephosphorylation: speed, convenience, and the need for only small amounts of cells or chromatin. Core histones and their acetylated forms can also be separated in gels containing 0.4% Triton X-100. The difference in electrophoretic mobility between mitotic (superphosphorylated) and interphase H1 from HeLa cells is approximately twice as great at neutral pH as at pH 4.5, making it possible to separate these two H1 forms rapidly and easily in Hepes/histidine "minigels" only 5-cm long. Total histones can be rapidly prepared by simply neutralizing 0.2 N HCl extracts, and the entire analysis, from harvesting cells to destaining gels, can be carried out in 1 day. The stacking effect of the disc system produces sharp bands and high resolution even with relatively dilute samples. 相似文献