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91.
92.
Synopsis Deviations from morphological intermediacy in six first generation hybrids between three hatchery strains of rainbow trout,
raised in a common environment, are reported. Hybrids have higher mean counts of four meristic characters than their maternal
parental strain in a significantly greater number of cases (18 out of 24). Furthermore, eight of eleven hybrid indices are
not intermediate. These results are discussed in reference to several mechanisms and models proposed to account for observed
responses of meristic characters to environmental and genetic influences. 相似文献
93.
A study of 138 patients with psoriasis--74 with psoriasis alone and 64 with psoriatic arthritis--revealed a significantly increased frequency of the HLA antigens A1, A28, B13, DR7 and MT3 in those with psoriasis alone and of Bw39 in those with psoriatic arthritis. The frequency of B17 was higher in both patient groups than in a control group of healthy individuals. The frequency of DRw6 was slightly higher in the patients with psoriasis alone (17.8%) than in the controls (4.7%), and that of DR7 was higher in the patients with psoriatic arthritis (52.9%) than in the controls (32.6%). Elevated levels of serum IgG and IgA along with positive results of tests for antinuclear antibody or rheumatoid factor or both were present in less than a tenth of the patients with psoriatic rash alone and in up to a third of those with psoriatic arthritis. Psoriatic arthritis was found to be less likely to develop in patients with purely guttate psoriasis than in those with other types of psoriasis. Clinical subtypes of psoriatic rash or psoriatic arthritis were not associated with the presence of particular HLA antigens. 相似文献
94.
Degradation of Thyrotropin-Releasing Hormone and Luteinising Hormone-Releasing Hormone by Enzymes of Brain Tissue 总被引:2,自引:0,他引:2
Abstract: In this article, the enzymes of brain and associated tissues that can degrade thyrotropin-releasing hormone (TRH) and luteinising hormone-releasing hormone (LH-RH) are reviewed. As both TRH and LH-RH are considered to act as neurotransmitters or neuromodulators in the CNS, attention is paid to the subcellular location of the enzymes described and how their topographies and substrate specificities fit them to playing roles as inactivating agents for TRH and LH-RH or as regulators of intracellular concentrations of TRH and LH-RH. Consideration is also given to enzymes involved in biotransformation of TRH to secondary metabolites that exhibit biological activity and to enzymes involved in the metabolism of secondary metabolites. 相似文献
95.
Lucas E. Castelli Raquel M. Gleiser Moira Battán-Horenstein 《Ecological Entomology》2020,45(3):718-726
1. Direct consumption of organic matter by the saprophagous larvae provides the ecosystem with a fundamental service by recycling nutrients and reducing exposure to decomposing matter. The present study aimed to assess the functional role of saprophagous flies in the mass loss of different types of decomposing organic matter. 2. Two types of common urban waste were used to measure the role of flies in reducing organic matter: chicken viscera (chicken) and a mixture of flour and uncooked eggs (flour and eggs), representing leftover food. Ten traps baited with each substrate, under field conditions, allowed fly access (exposed to flies) and three traps from each substrate did not (unexposed controls); adult flies entering the traps or emerging from the substrates and substrate mass loss were recorded. 3. Species from Calliphoridae, Sarcophagidae, Muscidae, and Fanniidae families were collected mainly in traps baited with chicken, with Phoridae being the most abundant in traps with flour and eggs as bait. A significantly richer (P < 0.05) assemblage of fly species accessed the traps baited with chicken viscera (21 species) compared with those emerging (11 species), whereas similar numbers of species accessed (n = 5) or emerged (n = 1) from traps baited with flour and eggs (average richness accessing 7.97, emerging 2.83). Chicken substrate mass loss and species richness were positively related (r = 0.56, P = 0.001). In traps where richness was larger than 10 species, the substrates were reduced by more than 85% of their initial weight compared with unexposed controls, which lost 30%. Substrate mass loss significantly increased with the abundance of flies (r = 0.73, P < 0.0001). 4. The results of the present study support the functional role of saprophagous species diversity on the decomposition rates of organic matter, reinforcing the negative consequences of loss or gain of species in modified landscapes and for ecosystem function. 相似文献
96.
Acidic glycosaminoglycans in developing sterno-costal cartilage of the hydrocephalic (ch+/ch+) mouse
Moira Breen Robert Richardson W. Bondareff H.G. Weinstein 《Biochimica et Biophysica Acta (BBA)/General Subjects》1973,304(3):828-836
The sterno-costal cartilage of the hydrocephalic mouse carrying the autosomal recessive gene (ch+/ch+) has 40 ± 3% of the acidic glycosaminoglycan concentration of the normal control containing the satin marker (+sa/+sa). The acidic glycosaminoglycan concentration of the sterno-costal cartilage in the heterozygous mouse (ch+/+sa) is significantly higher (114 ± 8%) than the normal control. The distribution of the acidic glycosaminoglycans in the sterno-costal cartilage is similar in the normal, heterozygous and homozygous mice at all stages of development studied, (prenatal, newborn and postnatal) being 78 ± 4% chondroitin 4(6)-sulfate and 22% hyaluronic acid and/or keratan sulfate. The concentration of acidic glycosaminoglycans in the sterno-costal cartilage decreases as development progresses in all three gene types of mice. The reduced level of acidic glycosaminoglycans in the sterno-costal cartilage of the autosomal recessive mouse, ch+/ch+, is associated with a defect in the formation of the sternum. The higher than normal acidic glycosaminoglycan concentration in the sterno-costal cartilage of the heterozygous mouse ch+/+sa is associated with delayed calcification of the sternum. This study characterizes the molecular locus of a defect in the extra-cellular matrix of a mouse carrying a lethal gene and may help in understanding proteoglycan disorders (mucopolysaccharidosis) in the human. 相似文献
97.
Over a three-year period (1959-1962), 122 children with essential nocturnal enuresis, observed at The Hospital for Sick Children, Toronto, used a waking apparatus for an average time of 3½ months. All were wet almost every night before the trial.At follow-up, the average duration of which was nine months, 50% were dry more than 7.5 nights out of 10. Thirty patients (40%) were completely dry.Since essential enuresis is probably due to an isolated maturational lag, progress in so-called “failures” of treatment can be measured in terms of an increasing initial dry interval between initiation of sleep and first voiding. 相似文献
98.
Functional characterization of Pneumocystis carinii brl1 by transspecies complementation analysis
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Pneumocystis jirovecii is a fungus which causes severe opportunistic infections in immunocompromised humans. The brl1 gene of P. carinii infecting rats was identified and characterized by using bioinformatics in conjunction with functional complementation in Saccharomyces cerevisiae and Schizosaccharomyces pombe. The ectopic expression of this gene rescues null alleles of essential nuclear membrane proteins of the Brr6/Brl1 family in both yeasts. 相似文献
99.
Maurizio Galderisi Francesco Marra Roberta Esposito Vincenzo Schiano Lomoriello Moira Pardo Oreste de Divitiis 《Cardiovascular ultrasound》2007,5(1):1-14
Morbidity and mortality rates are higher in patients with severe left ventricular (LV) systolic dysfunction and ECG-derived prolonged QRS interval than in those with normal QRS duration. QRS duration is currently used on the grounds that it reflects the presence of ventricular dyssynchrony. However, 30–40% of patients selected on the basis of a prolonged QRS do not receive benefit by cardiac resynchronization therapy (CRT) since they do not show any significant inverse LV remodeling and QRS duration does not accurately distinguish responders to CRT. Consequently, mechanical dyssynchrony (particularly intra-ventricular dyssynchrony) seems to be much more important than electrical dyssinchrony. Pre- and post-echocardiographic assessment should require the combination of conventional and specific applications ranging from M-mode and pulsed/continuous Doppler, to pulsed Tissue Doppler, the off-line analysis of colour Tissue Velocity Imaging, Strain Rate Imaging, and real time three-dimensional reconstruction However, there is not no consensus about the best approach and the best ultrasound parameter for selecting candidates to CRT and ECG representation of abnormal cardiac conduction still remains as the main criterion in guidelines. This review is a practical update of ultrasound methods and measurements of atrio-ventricular, inter-ventricular and intra-ventricular dyssynchrony and describes experiences which used either conventional Doppler echocardiography and more advanced techniques. By these experiences, the global amount of LV dyssynchrony seems to be critical: the greater intra-ventricular dyssynchrony, the higher the possibility of significant LV inverse remodeling. After CRT, it is necessary also to evaluate the optimal atrio-ventricular delay and ventricular-ventricular delay setting that maximizes LV systolic function. 相似文献
100.
Gračan R Buršić M Mladineo I Kučinić M Lazar B Lacković G 《Diseases of aquatic organisms》2012,99(3):227-236
We analysed the intestinal helminth community of 70 loggerhead sea turtles Caretta caretta with a curved carapace length ranging from 25 to 85.4 cm, recovered dead in neritic foraging habitats in the Adriatic Sea in 1995 to 2004. The overall prevalence of infection was high (70.0%), with a mean abundance of 36.8 helminth parasites per turtle. Helminth fauna comprised 5 trematodes (Calycodes anthos, Enodiotrema megachondrus, Orchidasma amphiorchis, Pachypsolus irroratus, Rhytidodes gelatinosus) and 3 nematodes (Sulcascaris sulcata, Anisakis spp., Hysterothylacium sp.), with 6 taxa specific for marine turtles. In terms of infection intensity and parasite abundance, O. amphiorchis was the dominant species (mean intensity: 49.8; mean abundance: 12.8), followed by R. gelatinosus (30.5 and 8.3, respectively) and P. irroratus (23.5 and 7.0, respectively), while larval Anisakis spp. exhibited the highest prevalence (34.3%). The intensity of helminth infection ranged from 1 to 302 (mean: 52.6 ± 69.1) and was not correlated with the size of turtles; this relationship held for all species, except R. gelatinosus (rS = 0.556, p < 0.05). In comparison to other marine habitats, the helminth community of Adriatic loggerheads is characterised by higher species diversity (Shannon-Wiener H' = 1.58) and evenness (E = 0.76), and lower dominance values (Berger-Parker d = 0.35), which can be attributed to the life history and feeding ecology of sea turtles in recruited neritic grounds and the diversity of their benthic prey. 相似文献