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51.
I C Kim 《The Journal of biological chemistry》1982,257(2):1063-1070
Rabbit antiserum produced against rat liver cytochrome H-450 was specific for cytochrome H-450. The antiserum did not react with hemolysate, microsomal and mitochondrial fractions of liver, and tissue extracts from heart, lung skeletal muscle, and testis of rat. With the monospecific antiserum, a rocket immunoelectrophoretic assay method was developed for the quantitation of the antigen with a sensitivity of 25 ng. By using rocket immunoelectrophoresis, the total amounts of the antigen found in liver, kidney, and brain of 20 rats were 33.6, 3.6, and 1.3 mg, respectively. It appears that the antigens in liver, kidney, and brain are immunologically identical. From immunological studies with subcellular fractions of rat liver, the antigen was found only in the postmicrosomal fraction. This indicates that the antigen is not a precursor or a proteolytic product of known cytochromes in mitochondria or microsomes. Therefore, cytochrome H-450 is a unique cytosolic protein found in brain, kidney, and liver. 相似文献
52.
53.
54.
Emin Oguzhan Oguz Hayati Yuksel Yasar Enli A. Cevik Tufan Gunfer Turgut 《Biological trace element research》2010,133(3):335-341
Copper is an essential trace element that is extremely toxic to organisms and organs at high doses. We have investigated the
histological and biochemical effects of a toxic dose of copper sulfate on the liver of term Ross broiler chicks. Fertilized
eggs were divided into three groups: experimental, injected with 50 mcg/0.1 ml copper sulfate in the air chambers on day 1;
sham, injected with 0.1 ml saline; and control, no injection. Term chicks were killed and their livers investigated histologically,
with hematoxylin–eosin-stained sections examined under light microscopy, and biochemically, for malondialdehyde and glutathione
levels. Histological examinations showed copper-treated samples with granular degeneration and necrosis of hepatocytes and
impairment to the cell lining of the remark cords. The samples had a congestive appearance, with blood in the vena centralis
and sinusoids, slight connective tissue increase, and lymphocyte infiltration. Control and sham group sections had normal
appearances. As oxidative damage parameters, in the copper-treated group, malondialdehyde levels were increased and glutathione
levels decreased. In the sham and control groups, there were no significant differences. At this toxic dose, copper sulfate
shows oxidative damage according to the histology of term chick liver that are confirmed biochemically by the changes in malondialdehyde
and glutathione levels. 相似文献
55.
The purpose of this review is to provide a global perspective on Oncorhynchus salmonine introductions and put-and-take fisheries based on modern stocking programs, with special emphasis on freshwater
ecosystems. We survey the global introductions of nine selected salmonines of the genus Oncorhynchus: golden trout, cutthroat trout, pink salmon, chum salmon, coho salmon, masu/cherry salmon, rainbow trout/steelhead, sockeye
salmon/kokanee, and chinook salmon. The information is organized on a geographical basis by continent, and then by species
and chronology. Two different objectives and associated definitions of ‘success’ for introductions are distinguished: (a)
seed introduction: release of individuals with the purpose of creating a wild-reproducing, self-sustaining population; and
(b) put-and-take introduction: release of individuals with the purpose of maintaining some level of wild population abundance,
regardless of wild reproduction. We identify four major phenomena regarding global salmonine introductions: (1) general inadequacy
of documentation regarding introductions; (2) a fundamental disconnect between management actions and ecological consequences
of introductions; (3) the importance of global climate change on success of previous and future introductions; and (4) the
significance of aquaculture as a key uncertainty in accidental introductions. We conclude this review with a recognition of
the need to terminate ongoing stocking programs for introduced salmonines worldwide. 相似文献
56.
57.
Giovanni Murtas 《Systems and synthetic biology》2010,4(2):85-93
One of the major properties of the semi-synthetic minimal cell, as a model for early living cells, is the ability to self-reproduce
itself, and the reproduction of the boundary layer or vesicle compartment is part of this process. A minimal bio-molecular
mechanism based on the activity of one single enzyme, the FAS-B (Fatty Acid Synthase) Type I enzyme from Brevibacterium ammoniagenes, is encapsulated in 1-palmitoyl-2oleoyl-sn-glycero-3-phosphatidylcholine (POPC) liposomes to control lipid synthesis. Consequently molecules of palmitic acid released
from the FAS catalysis, within the internal lumen, move toward the membrane compartment and become incorporated into the phospholipid
bilayer. As a result the vesicle membranes change in lipid composition and liposome growth can be monitored. Here we report
the first experiments showing vesicles growth by catalysis of one enzyme only that produces cell boundary from within. This
is the prototype of the simplest autopoietic minimal cell. 相似文献
58.
Background
Identifying essential genes in bacteria supports to identify potential drug targets and an understanding of minimal requirements for a synthetic cell. However, experimentally assaying the essentiality of their coding genes is resource intensive and not feasible for all bacterial organisms, in particular if they are infective. 相似文献59.
Background
Phylogenies capture the evolutionary ancestry linking extant species. Correlations and similarities among a set of species are mediated by and need to be understood in terms of the phylogenic tree. In a similar way it has been argued that biological networks also induce correlations among sets of interacting genes or their protein products. 相似文献60.