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61.
62.
Comparative analysis of the cattle and human genomes: detection of ZOO-FISH and gene mapping-based chromosomal homologies 总被引:6,自引:0,他引:6
Comparative chromosome painting with individual human chromosome-specific libraries (CSLs) on cattle metaphase chromosomes
delineated 46 homologous chromosomal segments between the two species. Continuous arrangement of these segments on individual
cattle chromosomes demonstrates a nearly complete coverage of the bovine karyotype and shows physical boundaries of bovine
chromosomal segments homologous to individual human chromosomes. Alignment of the available comparative gene mapping data
with the homologous segments strongly supports the detected gross homologies between the karyotypes of the two species. In
addition to cattle, four human CSLs were hybridized to sheep metaphase chromosomes also, to further verify the known karyotype
homology within the Bovidae. Besides its application to karyotype evolution research, the comparative knowledge provides for
rapid expansion of the much needed Type I locus-based bovine gene map.
Received: 9 September 1995 / Accepted: 4 December 1995 相似文献
63.
Nia J. Bryant Robert C. Piper Lois S. Weisman Tom H. Stevens 《The Journal of cell biology》1998,142(3):651-663
A large number of trafficking steps occur between the last compartment of the Golgi apparatus (TGN) and the vacuole of the yeast Saccharomyces cerevisiae. To date, two intracellular routes from the TGN to the vacuole have been identified. Carboxypeptidase Y (CPY) travels through a prevacuolar/endosomal compartment (PVC), and subsequently on to the vacuole, while alkaline phosphatase (ALP) bypasses this compartment to reach the same organelle. Proteins resident to the TGN achieve their localization despite a continuous flux of traffic by continually being retrieved from the distal PVC by virtue of an aromatic amino acid–containing sorting motif. In this study we report that a hybrid protein based on ALP and containing this retrieval motif reaches the PVC not by following the CPY sorting pathway, but instead by signal-dependent retrograde transport from the vacuole, an organelle previously thought of as a terminal compartment. In addition, we show that a mutation in VAC7, a gene previously identified as being required for vacuolar inheritance, blocks this trafficking step. Finally we show that Vti1p, a v-SNARE required for the delivery of both CPY and ALP to the vacuole, uses retrograde transport out of the vacuole as part of its normal cellular itinerary. 相似文献
64.
65.
Fazile Nur Ekinci Akdemir Berna Karagöz Recep Soslu Saleh H. Alwasel 《Journal of enzyme inhibition and medicinal chemistry》2016,31(6):114-118
AbstractThe antioxidant effects of ellagic acid (EA) and hesperidin (HES) against skeletal muscle ischemia/reperfusion injury (I/R) were performed. Hindlimb ischemia has been induced by tourniquet occlusion for 2?h on left hindlimb. At the end of ischemia, the tourniquate has been removed and initiated reperfusion for 2?h. EA (100?mg/kg) has been applied orally before ischemia/reperfusion in the EA?+?I/R group. HES (100?mg/kg) has been given orally in the HES?+?I/R group. The left gastrocnemius muscle has been harvested and stored immediately at??80?°C until assessed for the levels of MDA and antioxidant enzymes activities. MDA level has statistically increased in I/R group (p?<?0.05) compared to other groups. The muscle tissue antioxidant enzymes activities were lower than the other groups in the I/R group (p?<?0.05). EA and HES treatments significantly reversed the damage level in I/R, also activity of tissue SOD increased in the EA?+?I/R and HES?+?I/R groups. 相似文献
66.
67.
The heart is one of the least regenerative organs in the body, and highly vulnerable to the increasing incidence of cardiovascular diseases in an aging world population. Cell-based approaches aimed at cardiac repair have recently caused great public excitement. But clinical trials of patients’ own skeletal myoblasts or bone marrow cells for transplantation have been disappointing. Human embryonic stem cells (hESCs) form bona fide cardiomyocytes in vitro which are readily generated in mass culture and are being tested in animal models of heart damage. The early results, while encouraging, underscore that much remains to be done. This review focuses on the many challenges that remain before hESCs-mediated repair of the human heart becomes a reality. 相似文献
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70.
Christelle Hély Kelly K. Caylor Peter Dowty Samuel Alleaume Robert J. Swap Hank H. Shugart Christopher O. Justice 《Ecosystems》2007,10(7):1116-1132
Abstract
We present a regional fuel load model (1 km2 spatial resolution) applied in the southern African savanna region. The model is based on a patch-scale production efficiency
model (PEM) scaled up to the regional level using empirical relationships between patch-scale behavior and multi-source remote
sensing data (spatio-temporal variability of vegetation and climatic variables). The model requires the spatial distribution
of woody vegetation cover, which is used to determine separate respiration rates for tree and grass. Net primary production,
grass and tree leaf death, and herbivory are also taken into account in this mechanistic modeling approach. The fuel load
model has been calibrated and validated from independent measurements taken from savanna vegetation in Africa southward from
the equator. A sensitivity analysis on the effect of climate variables (incoming radiation, air temperature, and precipitation)
has been conducted to demonstrate the strong role that water availability has in determining productivity and subsequent fuel
load over the southern African region. The model performance has been tested in four different areas representative of a regional
increasing rainfall gradient—Etosha National Park, Namibia, Mongu and Kasama, Zambia, as well as in Kruger National Park,
South Africa. Within each area, we analyze model output from three different magnitudes of canopy coverage (<5, 30, and 50%).
We find that fuel load ranges predicted by the model are globally in agreement with field measurements for the same year.
High rainfall sustains green herbaceous production late in the dry season and delays tree leaf litter production. Effect of
water on production varies across the rainfall gradient with delayed start of green material production in more arid regions. 相似文献