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61.
62.
Revision of the coral genus Acropora (Scleractinia: Astrocoeniina: Acroporidae) in Indonesia 总被引:1,自引:0,他引:1
CARDEN C. WALLACE JACQUELINE WOLSTENHOLME 《Zoological Journal of the Linnean Society》1998,123(3):199-379
The coral genus Acropora is reviewed from Indonesia for the first time, following detailed collections made at 131 sites and additional material collected from approximately 40 sites throughout the archipelago during the period 1993–6. Eighty-three species are recorded, four of these ( Acropora halmaherae, A. awi, A. plumosa and A. simplex ) new to science, six first described in 1994 and six in 1997. Records are compared with specimen-based records from localities worldwide. The species of Acrokora occurring in Indonesian waters include five recorded only from the Indian Ocean and Indonesia, seven recorded only from the Pacific Ocean, South China Sea and Indonesia, and a further 10 species apparently endemic to Indonesia, as well as widespread Indo-Pacific species. Two species ( A. jacquelineae Wallace, 1994 and A. batunai Wallace, 1996) are recorded only from north central Indonesia and Papua New Guinea, and two species ( A. russelli Wallace, 1994 and A. turaki Wallace, 1994) only from north central Indonesia and north western Australia. The findings contribute to a new view of the corals of the Indo-Pacific 'centre of diversity' as a composite fauna with origins in a number of events in space and time. 相似文献
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64.
Corsini A Grignaffini P Beitz J Mest HJ Bellosta S Fumagalli R Paoletti R 《Cytotechnology》1993,11(1):S15-S17
The effect of trapidil derivative AR12456 on intracellular cholesterol metabolism was investigated in human hepatoma cell line HepG2. AR12456 enhanced the uptake and degradation of125I-LDL in a dose-dependent manner. The drug inhibited cholesterol synthesis and esterification without affecting cellular cholesterol content and bile acid synthesis; cholesterol efflux was slightly increased. These results show that the inhibition of cholesterol synthesis together with the enhanced expression of LDL receptors may partially explain the hypocholesterolemic activity of compound AR12456. 相似文献
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66.
Henri CM Heuven Rik HJ van Wijk Bert Dibbits Tony A van Kampen Egbert F Knol Henk Bovenhuis 《遗传、选种与进化》2009,41(1):4
Quantitative trait loci (QTL) affecting carcass and meat quality located on SSC2 were identified using variance component methods. A large number of traits involved in meat and carcass quality was detected in a commercial crossbred population: 1855 pigs sired by 17 boars from a synthetic line, which where homozygous (A/A) for IGF2. Using combined linkage and linkage disequilibrium mapping (LDLA), several QTL significantly affecting loin muscle mass, ham weight and ham muscles (outer ham and knuckle ham) and meat quality traits, such as Minolta-L* and -b*, ultimate pH and Japanese colour score were detected. These results agreed well with previous QTL-studies involving SSC2. Since our study is carried out on crossbreds, different QTL may be segregating in the parental lines. To address this question, we compared models with a single QTL-variance component with models allowing for separate sire and dam QTL-variance components. The same QTL were identified using a single QTL variance component model compared to a model allowing for separate variances with minor differences with respect to QTL location. However, the variance component method made it possible to detect QTL segregating in the paternal line (e.g. HAMB), the maternal lines (e.g. Ham) or in both (e.g. pHu). Combining association and linkage information among haplotypes improved slightly the significance of the QTL compared to an analysis using linkage information only. 相似文献
67.
Martinus AM van Boekel Erik R Vossenaar Frank HJ van den Hoogen Walther J van Venrooij 《Arthritis research & therapy》2001,4(2):87
The diagnosis of rheumatoid arthritis (RA) is primarily based on clinical symptoms, so it is often difficult to diagnose RA in very early stages of the disease. A disease-specific autoantibody that could be used as a serological marker would therefore be very useful. Most autoimmune diseases are characterized by a polyclonal B-cell response targeting multiple autoantigens. These immune responses are often not specific for a single disease. In this review, the most important autoantibody/autoantigen systems associated with RA are described and their utility as a diagnostic and prognostic tool, including their specificity, sensitivity and practical application, is discussed. We conclude that, at present, the antibody response directed to citrullinated antigens has the most valuable diagnostic and prognostic potential for RA. 相似文献
68.
BRIAN L. SPEARS MARK C. WALLACE WARREN B. BALLARD RICHARD S. PHILLIPS DERRICK P. HOLDSTOCK JOHN H. BRUNJES ROGER APPLEGATE MICHAEL S. MILLER PHILLIP S. GIPSON 《The Journal of wildlife management》2007,71(1):69-81
Abstract: Wild turkey (Meleagris gallopavo) broods spend the first several days of life on the ground until poult flight capabilities are attained. This is a critical period of wild turkey life history, with poult survival ranging from 12% to 52%. We measured vegetation in plots used by Rio Grande wild turkey (M. g. intermedia) preflight broods at 4 sites in southwest Kansas and the Texas Panhandle, USA, to determine microhabitat selection for ground roosting and to determine if microhabitat was related to poult survival. Hens selected ground-roost locations with more visual obstruction from multiple observation heights than random sites. Plots surrounding ground roosts had 1) greater visual obstruction; 2) increased tree decay; 3) higher percent grass, shrub, litter, and forb cover; and 4) lower percent bare ground cover than random sites. Grass, shrubs, and downed trees appeared to provide desired cover for ground-roosting broods. Poult survival increased with age of poult, size of brood, and density of shrubs 1–2 m tall. Plots used by broods <10 days old with above average survival contained more visual obstruction and shrubs than plots used by broods 10–16 days old with above average survival, signifying a shift in habitat use by successful broods as poults attain flight abilities. Density of shrubs 1–2 m tall in brood-use areas appears to be important for poult survival to 16 days of age on southern Great Plains rangeland habitats. Ground-level vegetative cover appears to be a significant factor in preflight poult survival. Provisions of ground-level vegetative cover should be considered during wild turkey brooding periods where increased poult survival is desired. 相似文献
69.
The influence of microhabitat on availability of drifting invertebrate prey to a net-spinning caddisfly 总被引:2,自引:0,他引:2
SUMMARY. 1. Invertebrate drift was sampled at both a rockface and a deep pebble riffle site in streams draining both a clearcut and a forested catchment.
2. A sampler was designed to separate the bottom 2 cm of flow, encompassing the effective range of caddisfly (Hydropsychidae: Trichoptera) catchnets. from upper flow.
3. No significant difference in drift density (numbers per cubie metre) was seen between sites within each stream. However, numbers per square centimetre intake area per day at the rockface sites were 4 times higher in the clearcut and 10 times higher in the forested stream than at the pebble-riffle site.
4. Rockface habitat which had highest drift availability was also the site of maximum secondary production of the predaceous collector- filterer Parapsyche cardis in both streams studied.
5. Increased sediment load in the clearcut stream may influence the efficiency of utilization of invertebrate drift by collector-filterers. 相似文献
2. A sampler was designed to separate the bottom 2 cm of flow, encompassing the effective range of caddisfly (Hydropsychidae: Trichoptera) catchnets. from upper flow.
3. No significant difference in drift density (numbers per cubie metre) was seen between sites within each stream. However, numbers per square centimetre intake area per day at the rockface sites were 4 times higher in the clearcut and 10 times higher in the forested stream than at the pebble-riffle site.
4. Rockface habitat which had highest drift availability was also the site of maximum secondary production of the predaceous collector- filterer Parapsyche cardis in both streams studied.
5. Increased sediment load in the clearcut stream may influence the efficiency of utilization of invertebrate drift by collector-filterers. 相似文献
70.
van Can HJ te Braake HA Bijman A Hellinga C Luyben KC Heijnen JJ 《Biotechnology and bioengineering》1999,62(6):666-680
There is a need for efficient modeling strategies which quickly lead to reliable mathematical models that can be applied for design and optimization of (bio)-chemical processes. The serial gray box modeling strategy is potentially very efficient because no detailed knowledge is needed to construct the white box part of the model and because covenient black box modeling techniques like neural networks can be used for the black box part of the model. This paper shows for a typical biochemical conversion how the serial gray box modeling strategy can be applied efficiently to obtain a model with good frequency extrapolation properties. Models with good frequency extrapolation properties can be applied under dynamic conditions that were not present during the identification experiments. For a given application domain of a model, this property can be used to considerably reduce the number of identification experiments. The serial gray box modeling strategy is demonstrated to be successful for the modeling of the enzymatic conversion of penicillin G In the concentration range of 10-100 mM and temperature range of 298-335 K. Frequency extrapolation is shown by using only constant temperatures in the (batch) identification experiments, while the model can be used reliable with varying temperatures during the (batch) validation experiments. No reliable frequency extrapolation properties could be obtained for a black box model, and for a more knowledge-driven white box model reliable frequency extrapolation properties could only be obtained by incorporating more knowledge in the model. Copyright 1999 John Wiley & Sons, Inc. 相似文献