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131.
E. Thies T. Jenkins F. Stutzenberger 《World journal of microbiology & biotechnology》1994,10(6):657-663
Tween 80 (0.1%, v/v) added to Thermomonospora curvata growing in minimal medium caused a transient lowering of the dry cell mass, decreased the optimal growth temperature of the thermophile from 62 to 54°C, and increased extracellular esterase activity. Cells grown in the presence of Tween 80 had decreased concentrations of branched chain fatty acids and increased concentrations of oleic acid. The detergent removed surface protuberances from mycelia and increased the liberation of enzymes active against crystalline cellulose, but did not stimulate liberation of enzymes active against carboxymethylcellulose, starch or pectin. 相似文献
132.
Frances Jurnak Marilyn D. Yoder Richard Pickergill John Jenkins 《Current opinion in structural biology》1994,4(6)
A new type of structural domain, composed of parallel β-strands folded into a coiled structure, has been observed in several protein structures within the past year. An analysis of the basic motif indicates that there are two distinct types, with variations likely to be discovered in the future. 相似文献
133.
134.
Mapping of Murine Fibroblast Growth Factor Receptors Refines Regions of Homology between Mouse and Human Chromosomes 总被引:1,自引:0,他引:1
Karen B. Avraham David Givol Aaron Avivi Avner Yayon Neal G. Copeland Nancy A. Jenkins 《Genomics》1994,21(3)
The genes for the fibroblast growth factor receptors Fgfr2, Fgfr3, and Fgfr4 have been mapped in the mouse using an interspecific backcross mapping panel. The Fgfr loci map to previously defined regions of homology between human and mouse chromosomes and provide additional information regarding human/mouse comparative mapping. 相似文献
135.
Leslie F. Lock Debra J. Gilbert Valerie A. Street Mary B. Migeon Nancy A. Jenkins Neal G. Copeland Bruce L Tempel 《Genomics》1994,20(3)
Cloning of the Drosophila Shaker gene established that a neurological phenotype including locomotor dysfunction can be caused by a mutation in a voltage-gated potassium (K) channel gene. Shaker sequences have been used to isolate a large family of related K channel genes from both flies and mammals. Toward elucidating the evolutionary relationship between loci and the potential causal connection that K channels may have to mammalian genetic disorders, we report here the genetic mapping of 12-16 different murine, voltage-gated K channel genes. We find that multiple genes, in some cases from distantly related K channel subfamilies, occur in clusters in the mouse genome. These mapping results suggest that the K channel gene subfamilies arose through ancient localized gene duplication events, followed by chromosomal duplications and rearrangements as well as further gene duplication. We also note that several neurologic disorders of both mouse and human are associated with the chromosomal regions containing K channel genes. 相似文献
136.
The effects of lipids on the glycosylation of recombinant human interferon- expressed in a Chinese Hamster Ovary cell line were investigated in batch culture. Lipids form an essential part of the N-glycosylation pathway, and have been shown to improve cell viability. In control (serum-free) medium the proportion of fully-glycosylated interferon- deteriorated reproducibly with time in batch culture, but the lipoprotein supplement ExCyte was shown to minimise this trend. Partially substituting the bovine serum albumin content of the medium with a fatty-acid free preparation also improved interferon- glycosylation, possibly indicating that oxidised lipids carried on Cohn fraction V albumin may damage the glycosylation process.Abbreviations BSA
bovine serum albumin
- CHO
chinese hamster ovary
- DHFR
dihydrofolate reductase
- FCS
foetal calf serum
- IFN-
human interferon-gamma
-
q
IFN
specific interferon production rate
-
specific growth rate
- 2N
doubly-gycosylated
- 1N
singly-glycosylated
- ON
non-glycosylated 相似文献
137.
Russell B. Lingham Keith C. Silverman Gerald F. Bills Carmen Cascales Manual Sanchez Rosalind G. Jenkins Suzanne E. Gartner Isabel Martin Maria T. Diez Fernando Peláez Sagrario Mochales Yu-Lin Kong Richard W. Burg Maria S. Meinz Leeyuan Huang Mary Nallin-Omstead Scott D. Mosser Michael D. Schaber Charles A. Omer David L. Pompliano Jackson B. Gibbs Sheo B. Singh 《Applied microbiology and biotechnology》1993,40(2-3):370-374
Chaetomellic acids A and B, isolated from Chaetomella acutiseta, are specific inhibitors of farnesyl-protein transferase that do not inhibit geranylgeranyl transferase type 1 or squalene synthase. Chaetomellic acids A and B are reversible inhibitors, resemble farnesyl diphosphate and probably inhibit FPTase by substituting for farnesyl diphosphate. Chaetomellic acid production appears to be widespread within the genus Chaetomella.
Correspondence to: R. B. Lingham 相似文献
138.
Submaximal,aerobic exercise training exacerbates the cardiomyopathy of postweanling Cu-depleted rats
Jeannette Davidson Denis M. Medeiros Robert L. Hamlin James E. Jenkins 《Biological trace element research》1993,38(3):251-272
To determine the dual effect of exercise training and copper depletion on myocardial function and ultrastructure, postweanling
rats were either trained or sedentary while fed copper-adequate or copper-deficient diets for 8 wk. Rats developed characteristic
myocardial subcellular degeneration and increased cardiac mitochondrial volume density when copper depleted, despite lack
of overt cardiac hypertrophy, hypertension, or anemia. Training combined with copper depletion induced mild left ventricular
hypertrophy. Basal laminae appeared fractionated in areas at capillary-myocyte interface, with focal pericapillary and interstitial
collagen accumulation, where-as overt fibrosis was absent or minimal. Electrocardiograms revealed increased QRS wave and QT
duration and notching of QRS complex with copper depletion, consistent with intraventricular conductance disturbances. The
oxidative capacity of soleus muscle increased with training in copper-adequate rats, but was reduced with progressive copper
depletion. These data suggest that copper depletion and training are synergistic in effecting focal accumulation of collagen,
with deleterious effect on exercise capacity. 相似文献
139.
Louis Faso Richard S. Trowbridge Wei Quan Xiu-Lan Yao Edmund C. Jenkins Alma Maciulis Thomas D. Bunch Henry M. Wisniewski 《In vitro cellular & developmental biology. Animal》1994,30(4):226-235
Summary A strain of cerebral endothelial cells was established from isolated cortical microvessels of caprine brain. These cells,
which are referred to as ECl cells, can be routinely subcultured to 32 passages without the loss of differentiated morphologic
and immunologic traits. The ability to routinely subculture ECl cells is an important asset, given that isolated cerebral
endothelial cells in mammals generally lose their differentiated traits after only 2 to 3 passages.
ECl cells were shown to contain Factor VIII-related antigen, which is a specific marker for cells of endothelial origin. ECl
cells morphologically demonstrated a scarcity of pinocytotic vesicles on their apical surfaces, a lack of trans-cytoplasmic
vesicles, and the ability to form in culture confluent monolayers with tight junctional complexes. Therefore, ECl cells possess
specific antigenic and ultrastructural features which classify them as being small vessel endothelial cells of the blood-brain
barrier type. Cytogenetic evaluation of ECl cells demonstrated a normal female goat 60,XX karyotype and confirmed the apparent
non-transformed nature of ECl cells due to the lack of chromosome abnormalities or rearrangements. Using scanning electron
microscopy, ECl cells were also shown to form confluent monolayers on mixed nitrocellulose filters, a feature that will enable
the development of an in vitro system to study trans-endothelial transport. Given that ECl cells are readily subcultured and
grow well on nitrocellulose filters, and that they resemble cerebral endothelium in vivo, it seems evident that ECl cells
can be used as a versatile model for the study of blood-brain barrier function, regulation, and pathology. 相似文献
140.
Rowan Jenkins 《The Botanical review》1993,59(2):81-111
A review of methods used in the taxonomy of the Fagaceae is presented, with a critical focus made on the nomenclature of extant and fossil taxa, notablyNothofagus. The most recent classifications of the family and the problems of character weighting are considered, and an argument is made to reduce the subfamilies to tribes. The origin of the cupule is then discussed. Interpretations of the cupule as a series of reduced dichasial axes are criticized for their essentialistic approach, lack of evolutionary evidence and failure of application to the family as a whole. With the postulating of an ancestral form, the origin of the cupule involving a combination of characters from an outer tripartite perianth whorl and the pericarp is proposed. The theory provides for the evolution of the thin-walled dry pericarp and all the cupule forms found in the family today. 相似文献