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961.
The distribution of noradrenaline and adrenaline in the brain of the urodele amphibian Pleurodeles waltlii has been studied with antibodies raised against noradrenaline and the enzymes dopamine--hydroxylase and phenylethanolamine-N-methyltransferase. Noradrenaline-containing cell bodies were found in the anterior preoptic area, the hypothalamic nucleus of the periventricular organ, the locus coeruleus and in the solitary tract/area postrema complex at the level of the obex. Noradrenergic fibers are widely distributed throughout the brain innervating particularly the ventrolateral forebrain, the medial amygdala, the lateral part of the posterior tubercle, the parabrachial region and the ventrolateral rhombencephalic tegmentum. Putative adrenergic cell bodies were found immediately rostral to the obex, ventral to the solitary tract. Whereas the cell bodies and their dendrites were Golgi-like stained, axons were more difficult to trace. Nevertheless, some weakly immunoreactive fibers could be traced to the basal forebrain. A comparison of these results with data previously obtained in anurans reveals not only several general features, but also some remarkable species differences.Abbreviations
Acc
Nucleus accumbens
-
AP
area postrema
-
Apl
amygdala, pars lateralis
-
Apm
amygdala, pars medialis
-
ca
commissura anterior
-
Cb
cerebellum
-
cc
central canal
-
Dp
dorsal pallium
-
epl
external plexiform layer
-
gl
glomerular layer of the olfactory bulb
-
H
ganglion habenulae
-
igl
internal granular layer
-
Ip
nucleus interpeduncularis
-
Lc
locus coeruleus
-
Ll
lateral line lobe
-
Lp
lateral pallium
-
Ls
lateral septum
-
ml
mitral cell layer
-
Mp
medial pallium
-
Ms
medial septum
-
nPT
nucleus pretectalis
-
NPv
nucleus of the periventricular organ
-
nV
nervus trigeminus
-
oc
optic chiasm
-
Poa
preoptic area
-
Ri
nucleus reticularis inferior
-
SC
nucleus suprachiasmaticus
-
sol
solitary tract
-
Str
striatum
- thd
thalamus dorsalis
-
thv
thalamus ventralis
-
To
tectum opticum
-
TP
tuberculum posterius
-
V
ventricle
-
VH
ventral hypothalamic nucleus
-
III
nucleus nervi oculomotorii
-
IXm
nucleus motorius nervi glossopharyngei
-
Xm
nucleus motorius nervi vagi 相似文献
962.
Esterase zymograms were obtained following polyacrylamide slab gel electrophoresis of protein extractsFusarium sambucinum and related species originating from different geographic locations and different matrices. The sites of esterase activity were recorded, and the Rfs were calculated. The data were used for the construction of phenograms by cluster analysis and nonlinear mapping by computerized classification techniques. The fifteen isolates ofF. sambucinum, the eight isolates ofF. torulosum and the six isolates ofF. spec. nov. each had identical profiles, and are therefore electrophoretically distinct species. The isolates ofF. sarcochroum, one ofF. sambucinum sensu lato (BBA 64280) and fifteen isolates ofF. sambucinum were electrophoretically indistinguishable from each other. We assume they are synonymous. The isolate ofF. bactridioides, one ofF. sambucinum sensu lato (BBA 64993) and eight isolates ofF. torulosum had uniform EST patterns, therefore the two species are electrophoretically identical. We assume they are also synonymous. The remaining three isolates ofF. sambucinum sensu lato are somewhat closely related toF. sambucinum isolates on the basis of our investigations. 相似文献
963.
Assumpció Bosch Stefan Wiemann Jordi Guimerá Wilhelm Ansorge David Patterson Xavier Estivill 《Human genetics》1995,95(1):119-122
Five clones, containing polymorphic CA-repeat sequences, have been isolated from a specific human chromosome 21 phage library and have been localised to band q21 of chromosome 21 using a somatic cell hybrid panel. These highly repetitive sequences (D21S1263, D21S1264, D21S1415, D21S1417 and D21S1420) have been characterised in the CEPH reference parents and have heterozygosities ranging from 0.30 to 0.81 and an average polymorphism information content (PIC) of 0.62. The relative order of these markers, based on the somatic cell hybrid panel, is cen-D21S1417, D21S1420-D21S1263, D21S1415-D21S1264-tel. The most polymorphic marker (D21S1264) has been included in the chromosome 21 genetic map. They have also been localised in the CEPH/ Généthon YAC panel, providing a refined localisation of these polymorphic sequences. These five CA-repeat markers should provide a better characterisation of the q21 region of chromosome 21. 相似文献
964.
Angela S. Barbosa Thaís E. Ferraz-Costa Mauro Semer Bernardo Liberman Carlos A. Moreira-Filho 《Human genetics》1995,95(1):63-66
This paper reports a case of XY gonadal dysgenesis in two sisters. Both patients presented an eunochoid female phenotype with normal external genitalia. At laparotomy, the elder sister was found to have bilateral gonadoblastoma. Cytogenetic studies, which included G and C banding and in situ hybridization, showed that the patients had an apparently normal 46, XY karyotype. PCR analyses revealed absence of the conserved portion (HMG box) of the SRY gene and of the Y chromosome pseudoautosomal boundary region sequence in both patients. The presence of the ZFY sequence was detected by Southern hybridization in the two affected sisters. The patients' father (46, XY, no mosaicism detected in peripheral blood lymphocytes) was positive for SRY and ZFY sequences. The occurrence of gonadoblastoma is discussed in terms of the genetic factors that may lead to tumor development. 相似文献
965.
Dinucleotide repeat polymorphism at the D4S2458 locus close to the PKD2 locus on human chromosome 4q
Miguel Viribay Dolores Tellería Eladio Velasco Felipe Moreno José L. San Millán 《Human genetics》1995,95(5):601-602
A new polymorphic CA repeat sequence was identified within the candidate region fot the autosomal dominant polycystic kidney disease type 2 (PKD2) locus. It should be a useful marker in the localization of this gene. 相似文献
966.
A. Falconi M. Borde A. Hernández-Cruz F. R. Morales 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1995,176(5):679-689
Stimulation of the spinal cord of the electric fish Gymnotus carapo, evoked an abrupt increase in the discharge rate of the electric organ. At the maximum of this response, the rate increased an average of 26 ± 11.8%. The duration of the response was 4.9 ± 2.12 s; its latency was 10.4 ± 1.1 ms. Activation of the Mauthner axon played a decisive role in this phenomenon as indicated by the following: (1) recordings from the axon cap of the Mauthner cell demonstrated that the response was evoked if the Mauthner axon was antidromically activated and (2) a response that was similar to that produced by spinal cord stimulation, was elicited by intracellular stimulation of either Mauthner cell. Stimulation of the eighth nerve could also increase the discharge rate of the electric organ. The effect was greater if a Mauthner cell action potential was elicited. The findings described in the present report, indicate the existence of a functional connection between the Mauthner cell and the electromotor system in Gymnotus carapo. This connection may function to enhance the electrolocative sampling of the environment during Mauthner-cell mediated behaviors. This is a novel function for the Mauthner cell.Abbreviations
EHP
extrinsic hyperpolarizing potential
-
EOD
electric organ discharge
-
M-AIR
Mauthner initiated abrupt increase in rate
-
M-cell
Mauthner cell
-
M-axon
Mauthner axon
-
PM
pacemaker nucleus
-
PM-cell
pacemaker cell
-
PPn
prepacemaker nucleus
-
SPPn
sublemniscal prepacemaker nucleus 相似文献
967.
In mixed culture of Lactobacillus hilgardii X1B and Leuconostoc oenos X2L, isolated from Argentinian wines, an amensalistic growth response was observed: Leuconostoc oenos did not grow, and after 24 h of incubation at 30°C no viable cells were detected. In pure and mixed cultures, Lactobacillus hilgardii produced hydrogen peroxide early in the growth cycle, reaching the maximum at 24 h. The values of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for the action of hydrogen peroxide on the growth of Leuconostoc oenos were: 4.08g ml-1 and 17.00 g ml-1 respectively. 相似文献
968.
[3H]Inositol accumulated by rat brain cultured astrocytes is released when cells swell by exposure to solutions of decreased osmolarity. Activation of inositol efflux was proportional to reductions in osmolarity from 30%–70%. This volume-activated inositol efflux pathway was increased (27%) in Na+-free medium and decreased (22%) in Cl–-free medium. It was independent of extracellular Ca2+ and was reduced (30%) in the presence of the intracellular chelator [1,2-bis(o-aminophenoxy) ethane-N,N,N,N-tetraacetic acid tetra-(acetoxymethyl)-ester] (BAPTA-AM). The inositol efflux pathway was markedly inhibited by Cl– channel blockers, which at maximal inhibitory concentrations decreased inositol efflux by 70%–83%. The potency range of the drugs was: 5-nitro-2-(3-phenylpropylamino)benzoic acid (NPPB)>1–9, dideoxyforskolin>4,4-diisothiocyanatostilbene-2,2-disulfonic acid (DIDS)>niflumic acid. Inositol efflux was strongly inhibited by the SH blocker N-ethyl maleimide (NEM), which at 100 M abolished inositol release. Inositol efflux can be reversed by increasing its extracellular concentration, suggesting that the efflux is mediated by a diffusional pathway whose direction is given by the concentration gradient. The inhibition of volume-associated fluxes of inositol by Cl– channel blockers supports the suggestion of an anion channel as the common pathway for inorganic and organic osmolytes in cultured astrocytes. 相似文献
969.
We have analyzed the patterns of DNase I/nick translation in the chromosomes of Rana perezi. The results show a nonuniform DNase sensitivity in different chromosome domains; the hypersensitivity appears to be concentrated at both the NOR and the distal regions. The resemblance to the situation in mammals, where active genes are DNase I hypersensitive, is discussed. 相似文献
970.
Molecular-genetic maps for group 1 chromosomes of Triticeae species and their relation to chromosomes in rice and oat 总被引:15,自引:0,他引:15
A E Deynze J C Nelson M E Sorrells S R McCouch J Dubcovsky J Dvorák K S Gill B S Gill E S Lagudah R Appels 《Génome》1995,38(1):45-59
Group 1 chromosomes of the Triticeae tribe have been studied extensively because many important genes have been assigned to them. In this paper, chromosome 1 linkage maps of Triticum aestivum, T. tauschii, and T. monococcum are compared with existing barley and rye maps to develop a consensus map for Triticeae species and thus facilitate the mapping of agronomic genes in this tribe. The consensus map that was developed consists of 14 agronomically important genes, 17 DNA markers that were derived from known-function clones, and 76 DNA markers derived from anonymous clones. There are 12 inconsistencies in the order of markers among seven wheat, four barley, and two rye maps. A comparison of the Triticeae group 1 chromosome consensus map with linkage maps of homoeologous chromosomes in rice indicates that the linkage maps for the long arm and the proximal portion of the short arm of group 1 chromosomes are conserved among these species. Similarly, gene order is conserved between Triticeae chromosome 1 and its homoeologous chromosome in oat. The location of the centromere in rice and oat chromosomes is estimated from its position in homoeologous group 1 chromosomes of Triticeae. 相似文献