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991.
Maira Oropeza Palmira Guevara Eva de García José Luis Ramírez 《Plant Molecular Biology Reporter》1995,13(2):182-191
Somaclonal variants resistant to sugarcane mosaic virus (SCMV) were obtained from susceptible sugarcane cv PR62258 through
somatic embryogenesis by increasing the number of subcultures of the embryogenic callus tissue in MS medium with 3 mg/L 2,4-dichlorophenoxyacetic
acid. Transfers were made at 30-day intervals for 1, 2 or 3 subcultures. Two somaclones, namely AT626 and BT627, were selected
by their resistance to SCMV. These subclones have maintained the resistance trait over seven years of testing in the field.
In this report we identified the somaclonal SCMV resistant variants from the maternal line and the nonresistant somaclones,
using the RAPD technique. 相似文献
992.
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
993.
G. Ramírez-Zarzosa F. Gil R. Latorre A. Ortega A. García-Alcaráz E. Abellán J. M. Vázquez O. López-Albors A. Arencibia F. Moreno 《Cell and tissue research》1995,280(2):217-224
Fibre-type differentiation of the lateral musculature has been studied in Sparus aurata (L.) and Dicentrarchus labrax (L.) during larval development. Histochemical and ultrastructural techniques show two presumptive muscle layers and two germinative zones of presumptive myoblasts. At hatching, myotomal muscle consists of a monolayer of thin undifferentiated cells near the skin (first germinative zone) overlying another mono-layer of small diameter fibres extending hypaxially and epaxially away from the transverse septum. Below this, there is a much thicker, deep layer of fibres, generally large in diameter and polygonal in shape. The presumptive myoblasts are located between these two layers of fibres in the second germinative zone. Initially, the superficial and deep muscle fibres show high and low myosin ATPase activity, respectively. Both layers grow by generating new fibres from the two mentioned germinative zones. At the end of larval life, the superficial layer changes its histochemical profile from high to low myosin ATPase activity and, at the same time, intermediate or pink muscle fibres can be observed by oxidative activity (the NADH-TR reaction). Morphometric analysis shows a significant increase in mean fibre diameter during successive ages, as shown by the Student's t-test (hypertrophic growth). Skewness and kurtosis values of fibre diameters point to the generation of a new fibre population from the germinative zones (hyperplastic growth). 相似文献
994.
Maritza Martínez Gladys Len De Pinto Sofía Alvrez Nola Gonzlez De Troconis Edgar Ocando Carlos Rivas 《Biochemical Systematics and Ecology》1995,23(7-8):843-848
An analytical study has been made of six gum specimens from Albizia lebbeck, Leguminosae. Galactose, mannose, arabinose, glucuronic acid and its 4-O--metyl analogue are present in all the specimens studied. Rhamnose was not detected according to sugar analysis and spectral data. The absence of this sugar, the high acidity and the relatively low limit viscosity number contrast with the values reported previously for one African sample of A. lebbeck. The lead content is much higher than that recorded for other Albizia gums. 13C-NMR spectrum of this gum, in deuterium oxide, shows good resolution. 相似文献
995.
Twenty-five accessions belonging to the genus Cytisus and allies (Genisteae: Leguminosae), potentially useful for agrosylvopastoral systems in the Mediterranean basin, were analyzed using isoenzymes. The aim was to assess the taxonomic usefulness of these characters at the specific and generic levels, and its value as an aid for the taxonomy. A high level of infrageneric and infraspecific variability was detected. Numerical analysis showed that isoenzymes are useful for the characterization both at the specific and generic levels. The obtained dendrogram supports the generic arrangement proposed by Bisby [(1981) Advances in Legume Systematics, Vol. 1, pp. 409–425], therefore helping to elucidate the difficult taxonomy of the studied species. 相似文献
996.
Cathy M. Tuck-Muller Harold Chen José E. Martínez Chuen-Cheh Shen Shibo Li Christine Kusyk Denise A. S. Batista Yogendra M. Bhatnagar Edmund Dowling Wladimir Wertelecki 《Human genetics》1995,96(1):119-129
Dicentrics are among the most common structural abnormalities of the human Y chromosome. Predicting the phenotypic consequences of different duplications and deletions of dicentric Y chromosomes is usually complicated by varying degrees of mosaicism (45,X cell lines), which may, in some cases, remain undetected. Molecular studies in patients with dicentric Y chromosomes have been few, and only two studies have attempted to determine the presence of SRY (the putative testis-determining factor gene). We report an 18-year-old female with short stature, amenorrhea, hirsutism, hypoplastic labia minora, and clitoromegaly who has a 45,X/46,X,idic(Y)(p11.32)/47,X,idic(Y)(p11.32),idic(Y) (p11.32) karyotype. Southern analysis using Y-specific probes (Y97, 2D6, 1F5, pY3.4) and polymerase chain reaction (PCR) analysis using primers for ZFY and SRY were positive for all loci tested, indicating that almost all of the Y chromosome was present. Our findings and an extensive review of the literature emphasize the importance of molecular analyses of abnormal Y chromosomes before any general conclusions can be reached concerning the relative effects of the Y-chromosome abnormality and mosaicism on sexual differentiation. 相似文献
997.
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
998.
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
999.
An autosomal dominant retinitis pigmentosa family with close linkage to D7S480 on 7q 总被引:7,自引:0,他引:7
José M. Millán Francisco Martínez Concha Vilela Magdalena Beneyto Félix Prieto Carmen Nájera 《Human genetics》1995,96(2):216-218
Retinitis pigmentosa is the most prevalent inherited disorder of the retina. It can be autosomal dominant (adRP), autosomal recessive (arRP) or X-linked (XLRP). A form of adRP mapping to chromosome 7q was reported in a large Spanish pedigree. We have typed DNA from the members of another Spanish family for polymorphic markers from the known candidate genes. Positive lod scores were obtained only for the markers located on 7q31-35, giving a maximum lod score of 2.98 (3.01 by multipoint analysis) at = 0.00 for D7S480. A brief clinical evaluation is given. 相似文献
1000.
Influence of the culture medium on the expression of surface polypeptides of Yersinia enterocolitica
Three polypeptides (200, 46, and 25 kDal) encoded by the virulence plasmid were detected by SDS-PAGE in the outer membrane of Yersinia enterocolitica 09 grown at 37°C in brain-heart infusion medium. Bacteria grown at the same temperature in the tissue culture medium RPMI 1640 expressed five additional polypeptides (170, 135, 118, 100, and 98 kDal), but the 25-kDal band was not seen. The protein profile in RPMI 1640 resembles the expression pattern displayed by yersiniae when grown in vivo. The immunoblot of total membrane proteins of bacteria grown in brain-heart infusion medium revealed eight plasmid-encoded polypeptides, four of which were also in the outer membrane preparations, including a 28-kDal polypeptide. These peptides do not coincide with known plasmid-encoded outer membrane proteins. 相似文献