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排序方式: 共有1211条查询结果,搜索用时 31 毫秒
1.
Drahomíra Kenov Lucie oltysov Michal Pravenec Marie-Pierre Moisan W. Theodore Kurtz Vladimír Ken 《Journal of Experimental Animal Science》2000,41(1-2)
The SHR-Lx congenic strain carrying a differential segment of chromosome 8 of BN and PD origin was recently shown to exhibit a significant decrease in blood pressure as compared to the SHR strain. There were two positional candidate genes for blood pressure control mapped to the differential segment: the rat kidney epithelial potassium channel gene (Kcnj1) and brain dopamine receptor 2 gene (Drd2). Bot these genes were separated into SHR.BN-RNO8 congenic substrains. In this communication, we are presenting the assignment of two further putative candidate genes, which might be involved in blood pressure control to the BN/PD differential segment of the SHR-Lx congenic strain. These are: the gene coding for smooth muscle cell specific protein 22 (Sm22) defined by the D8Mcw1 marker and neuronal nicotinic acetylcholine receptor gene cluster, defined by the D8Bord1 marker. Moreover, the glutamate receptor gene Grik4 which also maps to the differential segment of the SHR-Lx should be taken into account. The genetic separation of all these putative candidate genes of blood pressure control is being performed by recombinations and subsequent selection using (SHR×SHR-Lx) intercross population. 相似文献
2.
3.
Y H Gulcan N Duman A Kumral B Sa?olLebe S Kavuk?u D Er?al M Celilo?lu H Ozkan 《Genetic counseling (Geneva, Switzerland)》2001,12(3):263-267
Cerebrohepatorenal malformation is a rare familial disorder characterized by typical renal lesions combined with Dandy-Walker malformation, and congenital hepatic fibrosis. In this case report, a male premie with the diagnosis of cerebrorenal syndrome or so called Goldston syndrome is presented. Besides the rarity of this syndrome, this case is the second reported patient diagnosed prenatally. 相似文献
4.
Subcellular localization of the 84,000 dalton heat-shock protein in mouse neuroblastoma cells: evidence for a cytoplasmic and nuclear location 总被引:1,自引:0,他引:1
P M van Bergen en Henegouwen G Berbers W A Linnemans R van Wijk 《European journal of cell biology》1987,43(3):469-478
Using affinity-purified antibodies, the 84,000 dalton heat-shock protein (hsp) has been localized in mouse N2A neuroblastoma cells by immunocytochemical techniques. Immunofluorescence microscopy showed that hsp84 was present both in the cytoplasm and in the nucleus. The nucleoli were found to be unlabelled. Immunogold labelling on ultrathin cryosections revealed that hsp84 was evenly distributed throughout the entire cytoplasm. No preferential association of hsp84 with the plasma membrane or with membranes from organelles was observed. In the nucleus the hsp84 was present in both the euchromatin and heterochromatin. In the nucleolus only the fibrillar part was labelled and virtually no gold particles were observed in the granular part. A long-term hyperthermic treatment of 3 h at 42.5 degrees C was found to induce an accumulation of hsp84 inside the nucleus. No alterations in hsp84 distribution were observed during a treatment of the cells with 75 microM sodium arsenite for 3 h. Drastic alterations were observed in the nucleoli after both stress treatments. The granular part had totally disappeared and only remnants of the fibrillar part which contained hsp84, were found. Besides the nuclear accumulations of hsp84 during heat shock, no additional changes in the hsp84 location in stressed cells were observed. During a recovery from the heat shock by replacing the cells at 37 degrees C, a decrease in the nuclear location of hsp84 was observed, indicating the reversibility of this process. The significance of these results for the role of hsp84 in normal and in stressed cells is discussed. 相似文献
5.
Vladimír Křen Jiří Ludvík Olga Kofroňová Jaroslava Kozová Zdeněk Řeháček 《Applied microbiology and biotechnology》1987,26(3):219-226
Summary The 550-day semicontinuous cultivation of Claviceps fusiformis immobilized in calcium alginate is documented. The vegetative mycelium from seed or from early-production submerged culture is the best choice for immobilization. No extracellular glucans are produced by immobilized cells. Immobilized spores give low yields of clavine alkaloids. Alginate concentrations in a range of 2%–4% do not influence yield and spectrum of alkaloids. The cytoplasm of the immobilized cells becomes condensed (after 3 days), polysaccharides disappear, and centres of lipid synthesis are formed in the cytoplasm. After 60 days the cells harbour a great number of lipid particles, mitochondria are diminishing and their cristae partly disappear, indicating a decreased respiration capacity. After 350–500 days the volume of most cells is increased many times and the cells are filled with large oval bodies of electrondense material. Chloramphenicol protects immobilized cultures against bacterial contamination. 相似文献
6.
Ulrik Røen 《Hydrobiologia》1987,145(1):125-130
Chydorus arcticus n.sp. (Cladocera: Chydoridae: Chydorinae) is described, figured, and differentiated from the closely relatedC. sphaericus (O.F. Müller, 1785). The known distribution of the species is given, and some aspects of speciation of arctic crustaceans
are pointed out. 相似文献
7.
Miroslav Flieger Jaroslav Votruba Vladimír Křen Sylvie Pažoutová Viktor Rylko Přemysl Sajdl Zdeněk Reháček 《Applied microbiology and biotechnology》1988,29(2-3):181-185
Summary Kinetic parameters of production of clavine alkaloids were evaluated in twoClaviceps purpurea strains. Mutagenesis brought about enhanced resistance of the biosynthetic system towards alkaloids. Addition of glucose into the fermentation medium altered the zero order kinetics of production to activation-inhibition kinetics. The glucose treatment allowed performance of both elymoclavine-inhibitionless and clavine alkaloid-decompositionless fermentations if a combination of fermentation and separation units in a closed loop was used.Nomenlacture
k
1
rate constant of agroclavine synthesis (mg Agro · mg Elymo/l·g DW·day for stage 1, mg Agro/g DW·day for stage 2)
-
k
2
parameter describing inhibition of agroclavine formation rate by elymoclavine (mg Elymo/l)
-
k
3
specific rate of agroclavine decay (l/g DW·day)
-
k
4
maximal specific rate of elymoclavine synthesis (stage 1, 1/g DW·day, stage 2, mg Elymo/g DW·day)
-
k
4
–
maximal specific rate of elymoclavine synthesis in stage 1 (inhibition-activation mechanism) (mg Elymo/g DW·day)
-
k
5
physiological constant describing the elymoclavine decay rate (l2/g DW·day·mg Elymo)
-
k
5
–
physiological constant describing the activation of elymoclavine biosynthesis by elymoclavine (mg Elymo/l)
-
k
6
physiological constant describing the repression of elymoclavine biosynthesis by elymoclavine (mg Elymo/l)
-
k
7
maximal specific growth rate (1/day)
-
k
8
specific rate of biomass decay (l/g DW·day)
-
A
agroclavine concentration (mg/l)
-
E
elymoclavine concentration (mg/l)
-
r
A
specific rate of agroclavine biosynthesis (mg Agro/g DW·day)
-
r
E
specific rate of elymoclavine biosynthesis (mg Elymo/g DW·day)
-
r
i
specific rate of alkaloid biosynthesis (mg alkaloid/g DW·day)
-
X
dry biomass concentration (g/l)
-
specific growth rate (1/day)
Abbreviations Agro
agroclavine
- Elymo
elymoclavine
- Chano
chanoclavine
- DW
dry weight of biomass 相似文献
8.
In submerged Claviceps cultures the activity of hydroxymethylglutaryl-CoA reductase preceded the increase of alkaloid production and of sterol content. During the first alkaloid phase, cell mevalonate was involved in the biosynthesis of both alkaloids and steroids. In the second production phase, it was predominantly used for alkaloid synthesis. Hydroxymethylglutaryl-CoA reductase appears to be a suitable target for physiological manipulation to increase clavine alkaloid yields. 相似文献
9.
The phylogeny of the hominoid primates: a statistical analysis of the DNA-DNA hybridization data 总被引:1,自引:0,他引:1
Sibley and Ahlquist compared the single-copy nuclear DNA sequences of the
hominoid primates using DNA-DNA hybridization. From this data set they
estimated a phylogeny that clusters man and chimpanzees using a distance
Wagner procedure. However, no assessment of statistical confidence in this
estimated phylogeny was made, despite the fact that their data set contains
internal inconsistencies concerning the correct branching order. This paper
presents a modification of Pielou's Q- statistic that allows one to make
nonparametric tests of phylogenetic relationship from distance data. The
results of this analysis indicate that the estimated phylogeny of Sibley
and Ahlquist is without statistical significance owing to the internal
inconsistencies of the data set. A survey and additional analyses of other
types of molecular data indicate that the phylogeny that clusters
chimpanzees and gorillas and has the human lineage splitting off earlier is
statistically consistent with all the molecular data (including the DNA-DNA
hybridization data), whereas the phylogeny estimated by Sibley and Ahlquist
can be rejected at the 5% level using the data on restriction- endonuclease
sites in the mitochondrial genome.
相似文献
10.
O. Häppölä S. Soinila H. Päivärinta P. Panula O. Eränkö 《Histochemistry and cell biology》1985,83(1):1-3
Summary Using the immunoperoxidase technique in conjunction with specific antisera to -atrial natriuretic polypeptide (-ANP), it was shown that immunoreactive cell bodies and varicose fibers are widely distributed throughout the rat brain. The highest concentrations of -ANP-containing neuronal cell bodies and fibers were found in the hypothalamus and septum. This result confirms the radioimmunological determination of -ANP immunoreactivity in the rat brain. 相似文献