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81.
We have isolated the chicken LIS1 homolog, chLIS1, with DNA sequence similarity of over 68% to the human cDNA and 99% amino
acid identity. Additionally, we describe the pattern of chLIS1 expression in the chicken embryo. The early embryonic expression
is highly specific to the developing nervous system, whereas later the expression is more widespread.
Received: 16 February 1999 / Accepted: 30 March 1999 相似文献
82.
Cloning, structural organization, and chromosomal assignment of the porcine c-fos proto-oncogene, FOS 总被引:1,自引:0,他引:1
Reiner G Heinricy L Brenig B Geldermann H Dzapo V 《Cytogenetics and cell genetics》2000,89(1-2):59-61
The complete porcine c-fos proto-oncogene (FOS) with flanking regions was cloned and sequenced. FOS consists of four exons at amino acids 1-47, 48-131, 132-167, and 168-380 and includes all the typical motifs of the fos proto-oncogene. The promoter contains consensus sequences for CRE, SRE, CaRE, and the E-Box, as well as an AP-1 site. Homologies between human and swine were between 89.7% and 96.3% in the exons. Based on somatic cell hybrid panel screening and known homologies between swine chromosome 7 and human chromosome 14, the porcine c-fos gene was assigned to chromosome 7q23. 相似文献
83.
Biodegradation of Aliphatic-Aromatic Copolyesters by Thermomonospora fusca and Other Thermophilic Compost Isolates
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Ilona Kleeberg Claudia Hetz Reiner Michael Kroppenstedt Rolf-Joachim Müller Wolf-Dieter Deckwer 《Applied microbiology》1998,64(5):1731-1735
Random aliphatic-aromatic copolyesters synthesized from 1,4-butanediol, adipic acid, and terephthalic acid (BTA) have excellent thermal and mechanical properties and are biodegradable by mixed cultures (e.g., in compost). Over 20 BTA-degrading strains were isolated by using compost as a microbial source. Among these microorganisms, thermophilic actinomycetes obviously play an outstanding role and appear to dominate the initial degradation step. Two actinomycete strains exhibited about 20-fold higher BTA degradation rates than usually observed in a common compost test. These isolates were identified as Thermomonospora fusca strains. They appeared to be particularly suitable for establishment of rapid degradation tests and were used in comparative studies on the biodegradation of various polyesters. 相似文献
84.
An evaluation of field data from historical buildings in Germany showed that chemoorganotrophic bacteria are the most numerous microorganisms in building stones, followed by fungi and nitrifying bacteria. Chemoorganotrophic bacteria and fungi were present in almost every sample. Ammonia and nitrite oxidizers were found in 55 and 62% of the samples, respectively. Within months, natural stone was colonized by chemoorganotrophic microorganisms. The highest cell numbers were usually found near the surface. The colonization of natural stone by nitrifying bacteria took several years. The highest cell numbers were in some cases found underneath the surface. Nitrifying bacteria showed a preference for calcareous material with a medium pore radius between 1 and 10 m. Cell numbers of nitrifying bacteria did not correlate to the nitrate content of the stone material. We demonstrated that the stone inhabiting microflora can cause significant loss of nitrate by denitrification. Our data strongly suggested that microbial colonization of historical buildings was enhanced by anthropogenic air pollution. Samples taken from stone material with a pore radius 1 m had significantly higher cell numbers when they were covered with black crusts. A comparison of samples taken between 1990–1995 from buildings throughout Germany showed that in eastern Germany a significantly stronger colonization with facultatively methylotrophic bacteria and nitrifying bacteria existed. The same was true for natural stone from an urban exposure site when compared to material from a rural exposure site. Data from outdoor exposure and laboratory simulation experiments indicated that the colonization of calcareous stone by nitrifying bacteria was enhanced by chemical weathering. 相似文献
85.
A general approach is described for the implementation of a networked multi-unit computer integrated control system. The use
of data acquisition hardware and graphical programming tools alleviates tedious programming and maintains potency and flexibility.
One application of the control system, the control of a mammalian cell perfusion culture based on a key nutrient glucose concentration,
was demonstrated. The control system offers customized user interface for all process control parameters and allows the flexibility
for continued improvement and implementation of new tailored functions. The temperature, pH, dissolved oxygen and glucose
level were accurately controlled.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
86.
Monocyte-colony inhibition factor (M-CIF) was produced in microcarrier perfusion cultures from engineered Chinese hamster
ovary (CHO) cells. Three and fifteen liter microcarrier perfusion bioreactors equipped with internal spin filters were operated
for over two months. Approximately 60 L and 300 L of culture filtrate were harvested from the 3L and 15L microcarrier perfusion
bioreactors respectively. During the perfusion operation, cell density reached 2–6 × 106 cells/ml. Importantly, stable expression of M-CIF from the CHO cells under non-selection condition was maintained at a level
of 4–10 mg/L. Specific productivity was maintained at 1.8–3.4 mg/billion cells/day. The ability of the recombinant CHO cells
to migrate from microcarrier to microcarrier under our proprietary HGS-CHO-3 medium greatly facilitated microcarrier culture
scale-up and microcarrier replenishment. Future directions for microcarrier perfusion system scale-up and process development
are highlighted.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
87.
88.
The level of expression of sexually selected traits is generally determined by genes, environment and their interaction. In species that use multiple sexual signals which may be costly to produce, investing in the expression of one sexual signal may limit the expression of the other, favoring the evolution of a strategy for resource allocation among signals. As a result, even when the expression of sexual signals is condition dependent, the relative level of expression of each signal may be heritable. We tested this hypothesis in the East-Mediterranean barn swallow (Hirundo rustica transitiva), in which males have been shown to express two uncorrelated sexual signals: red-brown ventral coloration, and long tail streamers. We show that variation in both signals may partially be explained by age, as well as by paternal origin (genetic father-son regressions), but that the strongest similarity between fathers and sons is the relative allocation towards one trait or the other (relative expression index), rather than the expression of the traits themselves. These results suggest that the expression of one signal is not independent of the other, and that genetic strategies for resource allocation among sexual signals may be selected for during the evolution of multiple sexual signals. 相似文献
89.
Introduction
The association between short stature and increased risk of ischemic heart disease has been subject to studies for decades. The recent discussion of cardiovascular risk during growth hormone therapy has given new importance to this question. We have hypothesized that the autonomic system is a crucial element relating to this subject.Methods
Heart rate variability calculated from 24-hour electrocardiogram data is providing insight into the regulatory state of the autonomous nervous system and is an approved surrogate parameter for estimating cardiovascular risk. We have calculated heart rate variability during clonidine testing for growth hormone stimulation of 56 children. As clonidine is a well-known effector of the autonomous system, stimulating vagal tone and decreasing sympathetic activity, we compared the autonomous reactions of children with constitutional growth delay (CGD), growth hormone deficiency (GHD) and former small for gestational age (SGA).Results
During clonidine testing children with CGD showed the expected α2-adrenoreceptor mediated autonomous response of vagal stimulation for several hours. This vagal reaction was significantly reduced in the SGA group and nearly non- existent in the GHD group.Discussion
Children with GHD show a reduced autonomous response to clonidine indicating α2-adrenoreceptor sub sensitivity. This can be found prior to the start of growth hormone treatment. Since reduction of HRV is an approved surrogate parameter, increased cardiovascular risk has to be assumed for patients with GHD. In the SGA group a similar but less severe reduction of the autonomous response to clonidine was found. These findings may enrich the interpretation of the data on growth hormone therapy, which are being collected by the SAGhE study group. 相似文献90.
Johannes Ehler Sebastian Koball Martin Sauer Steffen Mitzner Heiko Hickstein Reiner Benecke Uwe K. Zettl 《PloS one》2015,10(8)