共查询到20条相似文献,搜索用时 15 毫秒
1.
Influence of different B-complex recombinants on the outcome of Rous sarcomas in chickens 总被引:3,自引:0,他引:3
Seven major histocompatibility (B) complex recombinants were evaluated for anti-Rous sarcoma response. In experiment 1, the BR5(F21-G19) recombinant haplotype both homozygous and in heterozygous combinations with B19 and B21 haplotypes were compared to B19/B19 and B21/B21 chickens to determine the relative influence of the BF versus BG chromosomal segments on regression of Rous sarcoma virus-induced tumours. In experiment 2, six recombinant haplotypes BR1(F24-G23), BR2(F2-G23), BR3(F2-G23), BR4(F2-G23), BR6(F21-G23) and BR8(F2-G2a,23) present in chickens heterozygous for normal haplotypes B19, B23 or B26 were compared for anti-sarcoma response. A total of 1328 chickens were blood typed for B alloanti-gens at 17 days of age, inoculated in the wingweb with Rous sarcoma virus at 6 weeks and monitored for anti-tumour immune response over a 10-week period. Genotypes which shared the same BF haplotype, but differed in their BG regions, had similar anti-tumour responses, implicating the BF but not the BG region in tumour regression. Chickens carrying BF2 or BF21 had a strong anti-tumour response, while BF24 conferred a weaker response, regardless of the accompanying normal haplotype. 相似文献
2.
Distribution of hereditary blood groups among Indians in South America. I. In Ecuador 总被引:5,自引:0,他引:5
G A Matson H E Sutton J Swanson A R Robinson A Santiana 《American journal of physical anthropology》1966,24(1):51-69
Blood specimens were procured from 658 Quechua, 36 Colorado, 233 Jivaro, 244 Cayapa, and 48 Secoya Indians of Ecuador. These were examined for antigens in the A-B-O, M-N-S-s, P, Rh-Hr, Lutheran, K-k, Lewis, Duffy and Kidd systems and for Diego (Dia), Wright (Wra), and Berrens (Bea) agglutinogens as well. Hemolystes were prepared and studied for hemoglobin types and the serum samples were tested for haptoglobins and transfserrins. Gene frequencies are high for O, M, s, R1, (CDe), R2 (cDE), Lub, k, Kpb, Leb and Fya; and low or absent for A, B, N, S, Mia, Vw, Mta, R0 (cDe), V (ces), Lua, K, Kpa, Lea, Fyb, Jsa, Wra and Bea. The Diego (Dia) gene is present but its frequency varies greatly from tribe to tribe. Gene frequency Hp1 is well within the range previously reported for Indians in Middle America excepting the Colorado in which population the frequency of 0.889 is unusually high. All 723 serum specimens tested for transferrins were C or CD. No D or BC types were found. All Ecuadorian Indian bloods tested electrophoretically contained only hemoglobin (A) as a major component. 相似文献
3.
Summary We have studied the regulation of two cysteine biosynthetic enzymes in S. typhimurium merodiploid strains which are heterozygous at the cysB regulatory locus. This gene codes for an element of positive control which is necessary for the expression of the enzymes of the biosynthetic pathway. Under conditions of sulfur deprivation levels of sulfite reductase (coded for by cysI, cysJ and cysG) and of O-acetylserine sulfhydrylase (coded for by cysK) are derepressed in cysB
+ haploid strains, but not in cysB
- haploid strains. Growth on a rich sulfur source such as l-cystine results in low levels of both enzyme activities in cysB
+ and cysB
- haploid strains but not in cysB
c haploid strains, where enzyme expression is constitutive, i.e. substantially greater than in a cysB
+ strain grown on l-cystine, regardless of the nutrients used for growth.We find that cysB
-/F cysB
+ merodiploid strains can be derepressed for sulfite reductase and O-acetylserine sulfhydrylase by growth on a poor sulfur source, and therefore cysB
+ is dominant to cysB
-. Enzyme levels are also derepressed in l-cystine-grown cysB
c/F cysB
+ strains indicating that cysB
c is dominant to cysB
+. The cysB484 allele is known to be cysB
- in regard to the regulation of sulfite reductase activity, but cysB
c with respect to O-acetylserine sulfhydrylase. In a cysB484/F cysB
+ strain the cysB
- character of cysB484 is recessive to cysB
+, while cysB
c is dominant to cysB
+.Merodiploids of the type cysB
-/F cysB
+, bearing chromosomal point mutations are derepressed by sulfur deprivation to levels which are either less than, equal to, or greater than those of wild type. These results can be explained by assuming a multimeric structure for the cysB protein and the formation in merodiploids of cysB
-/cysB
+ hybrid molecules with altered capacities for gene activation. The dominance of cysB
c over cysB
+ indicates that in contrast to the araC regulatory protein, which acts as both a gene activator and repressor, the cysB protein serves only as an element of positive control. 相似文献
4.
Summary
Escherichia coli rnh mutants deficient in ribonuclease H (RNase H) are capable of DNA replication in the absence of protein synthesis. This constitutive stable DNA replication (SDR) is dependent upon the recA
+ gene product. The requirement of SDR for recA
+ can be suppressed by rin mutations (for recA+-independent), or by lexA(Def) mutations which inactivate the LexA repressor. Thus, there are at least three genetically distinct types of SDR in rnh mutants: recA
+-dependent SDR seen in rnh
- rin+ lexA+ strains, recA
+-independent in rnh
- rin- lexA+, and recA
+-independent in rnh
- rin+ lexA(Def). The expression of SDR in rin
- and lexA(Def) mutants demonstrated a requirement for RNA synthesis and for the absence of RNase H. The suppression of the recA
+ requirement by rin mutations was shown to depend on some new function of the recF
+ gene product. In contrast, the suppression by lexA-(Def) mutations was not dependent on recF
+. The lexA3 mutation inhibited recA
+-dependent SDR via reducing the amount of recA
+ activity available, and was suppressed by the recAo254 mutation. The SDR in rnh
- rin- cells was also inhibited by the lexA3 mutation, but the inhibition was not reversed by the recAo254 mutation, indicating a requirement for some other lexA
+-regulated gene product in the recA
+-independent SDR process. A model is presented for the regulation of the expression of these three types of SDR by the products of the lexA
+, rin+ and recF
+ genes. 相似文献
5.
M. Rodríguez-Quijano M. T. Nieto-Taladriz J. M. Carrillo 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,93(1-2):295-299
The storage proteins and isozymes of two accessions of Aegilops longissima, and the F2 progeny from the cross between them, were analyzed. Six loci were identified on the 1Sl chromosome: Glu-S
l
1 (coding for HMW subunits of glutenin), Gpi-S
l
1 (coding for a Gpi isozyme), Glu-S
l
3 (coding for LMW subunits of glutenin), Gli-S
l
1 (coding for gliadins) and two, so far, not described new loci Gli-S
l
4 and Gli-S
l
5. The Gli-S
l
4 locus codes for a -gliadin and the Gli-S
l
5 codes for a gliadin with mobility in the -region. The genetical distances found between the six loci allowed the establishment of the following gene order on the 1Sl chromosome: Glu-S
l
1 —centromere —Gpi-S
l
1 — Gli-S
l
4 — Gli-S
l
3 — Gli-S
l
1 -Gli-S
l
5. 相似文献
6.
Above-ground productivity of dominant freshwater, brackish, and salt-marsh species from the U.S. Gulf Coast was evaluated using both gas exchange techniques and harvest methods. Both techniques showed significant differences in productivity among the study species which represent major components of their respective communities. Estimates of net aerial primary productivity using the harvest method yielded 3683 g dw (dry weight) m?2yr?1 for Spartina alterniflora (tall), 2008 g dw m?2yr?1 for S. alterniflora (short), 3677 g dw m?yr?1 for S. patens and 1641 g dwm?yr?1 for Panicum hemitomon. Carbon balance estimated from gas exchange calculation yielded values approximately equivalent to a biomass accumulation of 6024 g dw m?2yr?1 for S. alterniflora (tall), 3047 g dw m?yr?1 for S. alterniflora (short), 5702 g dw m?yr?1 for S. patens, and 2912 g dm?yr?1 for P. hemitomon. The net aerial primary production was estimated to be approximately 61% of total productivity in S. alterniflora (tall-form) and 66%o of total productivity in short-form, 64% in S. patens and 56%) in P. hemitomon. The assimilation data also indicated that Spartina alterniflora and S. patens continue carbon fixation throughout the year while assimilation in Panicum hemitomon is absent due to lack of live leaves during the winter. Various aspects of harvest and gas exchange techniques are discussed. 相似文献
7.
Summary NADPH oxidase of phagocytic leucocytes contains a membrane cytochromeb with two subunits, gp91
phox
and p22
phox
, together with three cytosolic proteins, p47
phox
, p67
phox
and p2
rac
. The presence of some of these components has been sought in non-phagocytes, using Western blot analysis for protein expression and PCR to amplify and detect mRNA. All components were detected in EBV-transformed B lymphocytes and peripheral blood B lymphocytes. Fibroblasts and human kidney mesangial cells contained mRNA for p67
phox
, p47
phox
, and p22
phox
but not gp91
phox
. Levels of expression varied with growth conditions, but it appears possible than an isozyme of cytochromeb which lacks gp9
phox
is present in these cells. Proteins of p47
phox
and p67
phox
were expressed, in low concentrations, in these two cell types. Expression of mRNA for p47
phox
and p67
phox
was found to be widespread in many cell types.Abbreviations IL-1
interleukin 1
- PMA
phorbol myristate acetate
- CGD
chronic granulomatous disease
- EBV-BL
Epstein-Barr virus transformed B-lymphocytes
- PBBL
peripheral blood B lymphocytes 相似文献
8.
Edwin A. Azen 《Biochemical genetics》1976,14(3-4):225-235
Electrophoresis of human tears on slab polyacrylamide gels showed five phenotypes among anodal tear proteins. These phenotypes are the expression of autosomal codominant alleles. Gene frequencies are as follows: for Caucasians, At
1=0.99, At
3=0.01; for Negroes, At
1=0.97, At
2=0.03; for Chinese, At
1=0.98, and At
4 and At
5 are both approximately 0.008.This study was supported by a grant from the National Institutes of Dental Research (5-R01-DE-E-03658-10). 相似文献
9.
R. E. Denell 《Genesis (New York, N.Y. : 2000)》1982,3(2):103-113
When heterozygous, dominant mutant alleles of the Polycomb locus are associated with a variety of adult homoeotic effects. Zygotes homozygous for these alleles die as late embryos showing homoeotic transformation of head, thoracic, and abdominal segments. This study shows that embryos homozygous for Pc3 are more extreme than those homozygous for Pc1 or Pc2. Moreover, Pc1/Pc3 heterozygotes are more extensively transformed if their mothers were Pc3/ + than if they were Pc1/ +; this effect does not depend on zygotic genetic background and must be maternal in nature. Embryos homozygous for Pc3 are less extreme if they arise from Pc3/ + / + than from Pc3/ + mothers. These results strongly suggest that the Polycomb locus acts maternally as well as zygotically to affect early determinative decisions. 相似文献
10.
The effects of 24 hr light-dark cycles on the circadian conidiation rhythm inNeurospora crassa were compared among will-typefrq
+ and clock mutantsfrq
+,frq
3,frq
7,frq
9 andfrq
11. The minimum length of the light period necessary for complete entrainment to the light-dark cycles was almost 2 hr infrq
+,frq
3 andfrq
7 strains. The minimum duration of the dark period necessary for the appearance of circadian conidiation was almost 4 hr in
all of the strains except thefrq
11 strain. The phase of the conidiation rhythm was dependent on the light to dark transition in thefrq
1 strain in all light-dark cycles examined and in thefrq
+ andfrq
3 strains when the light period was shorter than 16 hr. In contrast, the phase of thefrq
7 strain was dependent on the light to dark transition when the light period was shorter than 10 hr. 相似文献
11.
M. Strnad 《Journal of Plant Growth Regulation》1996,15(4):179-188
Enzyme-linked immunosorbent assays (ELISAs) were developed for determination of N
6-benzyladenosine, N
6-(meta-hydroxybenzyl)adenosine, and structurally related cytokinins. The use of the ELISAs allowed detection over the range of 0.05–70 pmol for N
6-benzyladenine and 0.01–20 pmol for the N
6-(meta-hydroxybenzyl)adenine cytokinins. Polyclonal antibodies used in the assays were specific for N
6-benzyladenine and N
6-(meta-hydroxybenzyl)adenine and their corresponding N
9-substituted derivatives. By the use of internal standardization, dilution assays, authentic [2-3H]cytokinin recovery markers, and immunohistograms, the ELISAs have been shown to be applicable for the estimation of N
6-benzyladenine and N
6-(meta-hydroxybenzyl)adenine-type cytokinins in plant tissues. For the analysis of cytokinins in the tissues of young poplar leaves and Solarium teratoma shoot culture, the extracts were fractionated by high performance liquid chromatography (HPLC) and the fractions analyzed by ELISAs. Immunohistogram ELISA analysis of fractions from different HPLC systems indicated major peaks of immunoreactivity co-chromatographing with the labeled and unlabeled standards of N
6-benzyladenine, N
6-meta-hydroxybenzyl)adenine, and their N
9-glycosides in these tissues.Abbreviations ELISA
enzyme-linked immunosorbent assay
- FW
fresh weight
- (mOH)[9R]BAP
N
6-(meta-hydroxybenzyl)adenosine
- HPLC
high performance liquid chromatography
- TBS
Tris-buffered saline
- TEAA
triethylammonium acetate
- [9R]BAP
N
6-benzyladenosine 相似文献
12.
Kenneth J. Goldman Steven Branstetter John A. Musick 《Environmental Biology of Fishes》2006,77(3-4):241-252
Age and growth estimates for sand tiger sharks, Carcharias taurus, in the western North Atlantic were derived from 96 vertebral centra collected from sharks ranging from 94 to 277 cm total length (TL), and compared to previously published age and growth data. The oldest female and male sand tiger sharks aged in this study were 17 and 15 years of age, respectively. von Bertalanffy growth parameters derived from vertebral length-at-age data are L
∞ = 295.8 cm TL, k = 0.11 year−1, and t
0 = −4.2 years for females, and L
∞ = 249.5 cm TL, k = 0.16 year−1, and t
0 = −3.4 years for males. Sexual maturity is estimated to be 9–10 years for females and 6–7 years for males. Weight-to-length relationships determined for female and male sand tiger sharks in the western North Atlantic are; W = 1.3 × 10−4 × L
2.4 (r
2
= 0.84, n = 55) and W = 9.0 × 10−5 × L
2.5 (r
2
= 0.84, n = 47), respectively, and 7.9 × 10−5 × L
2.5 (r
2
= 0.84) for the sexes combined. Our results show sand tigers possess a slower rate of growth than previously thought. This information is crucial for accurately assessing this population’s ability to recover, and further justifies the need for this species to be fully protected. 相似文献
13.
The influence on the excess scattering function P(μ) of flutuations in the electron density ρ within a macromolecule is treated, to the approximation that the solvent is a structureless medium of constant electron density ρ0. The results for P(μ) and the apparent value of the mean square radius Rapp2, can be expressed as functions of the excess electron density Δρ: P(μ) = X(μ) + (Δρ)?1Y(μ) + (Δρ)?2Z(μ) and Rapp2 = Rx2 + (Δρ)?1Ry2 + (Δρ)?2Rz2, where X(μ) and Rx2 depend only on the shape of the macromolecule, while Y(μ) and Ry2 as well as Z(μ) and Rz2 depend on the shape and the fluctuations in ρ. By varying the electron density of the solvent, the contributions of the shape and the internal structure of the macromolecule can be resolved. The quantities Rx2, Ry2, and Rz2 are evaluated for seven models to illustrate the relative importance of these contributions for representative structures. 相似文献
14.
Several strains of mice were tested for their capacity to provide immunoglobulin L chains required for the expression of the major cross-reactive idiotype (CRIA) associated with p-azophenylarsonate-specific antibodies of strain A mice. To facilitate testing, mice were bred that were homozygous for Igh-C
e
and Lyt-2
a
, 3
a
, i. e., they possessed genes controlling H chains but not L chains required for expression of the CRIA. Such male mice were mated to females of various strains and their offspring were tested; expression of CRIA indicated the presence in the female parent of genes controlling the appropriate L chains. All females bearing the Lyt-2
a
, 3
b
or Lyt-2
b
, 3
b
genotype yielded offspring, most of which were CRI
A
+
, whereas all the offspring of females that were Lyt-2
a
, 3
a
were CRI
A
–
. The female parents included mice of several strains that are congenic for Lyt-2
a
, 3
b
, Lyt-2
b
, 3
b
or Lyt-2
a
, 3
b
, thus demonstrating very close linkage between the Lyt loci and the expression of CRIA. In addition, doubly congenic strains of mice with the heavy chain allotype of the CRI
A
+
AL/N strain and the Lyt-2
a
, 3
a
genotype on a BALB/c background failed to express CRIA. The data provide further evidence for the similarity of repertoires of L chains in Lyt-3
b
mice of various strains. When genes were present controlling A/J H chains and L chains of C57BL/6 or BALB/c origin, the quantitative expression of CRIA was only slightly lower than that observed in A/J mice. Mice possessing genes controlling the H or L chains required for CRIA expression, but not both, did not express CRIA but synthesized Ar-specific antibodies which contained low but significant concentrations of the idiotype-associated chain. 相似文献
15.
Relationship between Contents of Chlorophyll (a+b) (SPAD values) and Nitrogen of Some Temperate Grasses 总被引:3,自引:0,他引:3
In a field experiment the chlorophyll (a+b) (SPAD readings) and nitrogen contents of three grass species (Festuca arundinacea Schreb., Lolium perenne L., and Lolium multiflorum Lam.) and three intergeneric hybrids of Festuca pratensis Huds. × Lolium multiflorum Lam. and Festuca arundinacea Schreb. × Lolium multiflorum Lam. were measured. Close relationships were found between SPAD readings and nitrogen leaf content (r
2 = 0.873** 0.491** and 0.938**) for the 1st, 2nd, and 3rd cut, respectively. SPAD readings and N contents were closely correlated (r = 0.836**) confirming that SPAD measurements could be used in grass selection and/or breeding for high N concentration in herbage.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
16.
Maria V. Pulina Kenneth E. Sahr Sonja Nowotschin Anna‐Katerina Hadjantonakis 《Genesis (New York, N.Y. : 2000)》2014,52(5):417-423
Mixl1 is the only member of the Mix/Bix homeobox gene family identified in mammals. During mouse embryogenesis, Mixl1 is first expressed at embryonic day (E)5.5 in cells of the visceral endoderm (VE). At the time of gastrulation, Mixl1 expression is detected in the vicinity of the primitive streak. Mixl1 is expressed in cells located within the primitive streak, in nascent mesoderm cells exiting the primitive streak, and in posterior VE overlying the primitive streak. Genetic ablation of Mixl1 in mice has revealed its crucial role in mesoderm and endoderm cell specification and tissue morphogenesis during early embryonic development. However, the early lethality of the constitutive Mixl1?/? mutant precludes the study of its role at later stages of embryogenesis and in adult mice. To circumvent this limitation, we have generated a conditional Mixl1 allele (Mixl1cKO) that permits temporal as well as spatial control of gene ablation. Animals homozygous for the Mixl1cKO conditional allele were viable and fertile. Mixl1KO/KO embryos generated by crossing of Mixl1cKO/cKO mice with Sox2‐Cre or EIIa‐Cre transgenic mice were embryonic lethal at early somite stages. By contrast to wild‐type embryos, Mixl1KO/KO embryos contained no detectable Mixl1, validating the Mixl1cKO as a protein null after Cre‐mediated excision. Mixl1KO/KO embryos resembled the previously reported Mixl1?/? mutant phenotype. Therefore, the Mixl1 cKO allele provides a tool for investigating the temporal and tissue‐specific requirements for Mixl1 in the mouse. genesis 52:417–423, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
17.
Kochian L. V. Garvin D. F. Shaff J. E. Chilcott T. C. Lucas W. J. 《Plant and Soil》1993,155(1):115-118
Recently, two K+-transport cDNAs, KAT1 and AKT1, were cloned in Arabidopsis thaliana. These cDNAs had structural similarities to K+ channel genes in animals, and also conferred the ability for growth on micromolar levels of K+ when expressed in K+ transport-defective yeast mutants. In this study, we examined the possibility that KAT1 encodes the high-affinity K+ transport system that has been previously characterized in plant roots, by studying the concentration-dependent kinetics of K+ transport for KAT1 expressed in Xenopus oocytes and Saccharomyces cerevisiae. In both organisms, the K+ transport system encoded by KAT1 yielded Michaelis-Menten kinetics with a high Km for K+ (35 mM in oocytes, 0.6 mM in yeast cells). Furthermore, Northern analysis indicated that KAT1 is expressed primarily in the Arabidopsis shoot. These results strongly suggest that the system encoded by KAT1 is not a root high-affinity K+ transporter. 相似文献
18.
Summary Two multiply marked complementary strains namely Het
+ Nif+ Str-R and Het
- Nif- Ery-R MSO-R were constructed and crossed under conditions counterselective for the Het
+ Nif+ Str-R parent and selective only for recombinants of Str-R and Ery-R or Str-R and MSO-R constitution. The results of the recombinant analysis with regard to the selected and unselected markers suggested that the Het
- Nif- Ery-R MSO-R parent acted as a recipient and the Het
+ Nif+ Str-R parent as donor of the genetic markers in the cross. The joint inheritance of Het
+ and Nif
+ unselected markers among the recombinants was found to occur more frequently than the inheritance of the Het
+ or Nif
+ markers alone. The observed joint inheritance of Het
+ and Nif
+ markers among the recombinants probably results from the inheritance of the regulatory gene(s) required for the activation of latent het and nif genes. This interpretation is fully supported by (a) the frequency distribution of unselected Het
+ and Nif
+ markers and (b) the reversion frequency of Het
-
Nif
- strains to Het
+ Nif+ prototrophy. Accordingly the apparent close genetic linkage of het and nif genes is not due to their organization in a single operon but to their common regulation by regulatory gene(s) of a positive control nature. The Het
+ Nif+ wild type, mutant, revertant, and recombinant strains all appear similar in their NO
3
-
repression of both heterocyst and nitrogenase. The Het
+ Nif- and Het
- Nif+ recominants also show similar NO
3
-
repression of their heterocyst and nitrogenase respectively. The presence of only microaerobic acetylene reducing activity in Het
- Nif+ recombinants clearly indicates the heterocyst to be an organ for protection of nitrogenase against oxygen toxicity.Abbreviations CFU
Colony forming units
- Ery
erythromycin
-
Ery-R
erythromycin resistance
-
het
genotypic designation of genes required for heterocyst differentiation
-
Het
phenotype designation of genes required for heterocyst differentiation
- MSO
l-Methionine-dl-sulfoximine
-
MSO-R
MSO-resistance
- N2 medium
Chu 10 medium without combined nitrogen
- NH
4
+
medium
basic mineral medium with ammonium nitrogen
-
nif
genotype designation of genes required for N2 fixation
-
Nif
phenotype designation of genes required for N2 fixation
- NO
3
-
medium
Chu 10 medium supplemented with KNO3
- NTG
N-methyl-N-nitro-N-nitrosoguanidine
- r gene(s)
regulatory gene(s)
- Str
streptomycin
-
Str-R
streptomycin resistance
- Str-S
streptomycin sensitive 相似文献
19.
Distribution of hereditary factors in the blood of Indians of the Gila River, Arizona 总被引:3,自引:0,他引:3
G A Matson T A Burch H F Polesky J Swanson H E Sutton A Robinson 《American journal of physical anthropology》1968,29(3):311-337
This paper reports the distribution of blood groups, A-B-H secretors, haptoglobins, transferrins and hemoglobin types among Indians of the Gila River Valley in Arizona. Specimens were procured from the following putative full-bloods: 909 Pima, 37 Papago, and 124 Maricopa; and from the following known mixed-bloods: Pima-Papago 134, Pima-Maricopa 26, Pima-Other Indian 41, Pima-Caucasian 33. These 1304 samples were tested for factors in the A-B-O, M-N-S-s, P, Rh-Hr, Lutheran, Kell-Cellano, Lewis, Duffy, Kidd and Diego blood group systems, and for additional blood factors (Wra), Doa, Vel, Yta, Coa, Gya, Sav, and L. W. Serum samples were tested for haptoglobins and transferrins. Hemolysates, prepared from whole blood, were tested for hemoglobin types. The results are presented on appropriate tables as number and per cent of phenotypes for the various blood group antigens and their calculated allele frequencies. Locations of the populations from which blood samples were procured are shown on a map (fig. 1). Tests made by earlier workers on the blood of Arizona Indians and related tribes are presented for comparison and discussed. The usual high frequencies for allele O reported in Amerinds was found among the putatively full-blood Gila Indians; the 124 Maricopa presented the maximum frequency of 1.000. High frequencies were reported generally for M, s, P1, R1 (CDe), R2 (cDE), k (100%) Fy, and Doa alleles. Low frequencies were reported for N, S, r (cde), R° (cDe), fy, Le1w and Dia (Pima only). There was a wide variation in frequencies for jk, and Hp1, and there were 17 Transferrin Tf B1C observed in 270 Pima samples tested. All the remaining were classified as Tf C except two Tf B;C from mixed-bloods. All samples tested for Vel, Yta, Coa, Sav, and Hemoglobin (A) showed the maximum frequency (1.000) for their genes. The following antigens were completely absent: Lua, Mia, Vw, Mta, p, Pk, ry (CdE), K, and Wra. The results of this study suggests that the Papago tribe presents fewer genes of non-Indian origin than the Pima, and the Maricopa least of the three populations. 相似文献
20.
Opiate Receptor-Mediated Inhibition of Catecholamine Release in Primary Cultures of Bovine Adrenal Chromaffin Cells 总被引:10,自引:5,他引:5
Abstract: Primary cultures of chromaffin cells from bovine adrenal medulla were used to evaluate the ability of several opiates to reduce the release of catecholamines induced by stimulation of nicotinic receptors. Etorphine, β-endorphin, Met-enkephalin[Arg6,Phe7], and the synthetic peptide [d -Ala2,Me-Phe4,Met(O)s-ol]enkephalin inhibited the acetylcholine-induced release of catecholamines with an IC30 varying from 10?7 to 1 × 10?6M. The effect was stereospecific because levorphanol (IC30= 7.5 × 10?7M) was approximately two orders of magnitude more potent than dextrorphan. Morphine (μ-receptor agonist), [d -Ala2, d -Leu5]enkephalin (δ-receptor agonist), ethylketazocine (k -receptor agonist), and N-allylnormetazocine (σ-receptor agonist) were at least 100–1000 times less potent than etorphine. Diprenorphine (IC50= 5 × 10?7M) and naloxone (IC50= 10?6M) antagonized the effect of etorphine. High-affinity, saturable, and stereospecific binding sites for [3H]etorphine, [3H]dihydromorphine, [3H-d -Ala2,d -Leu5]enkephalin, [3H]ethylketazocine, and for [3H]N-allylnormetazocine, [3H]diprenorphine, and [3H]naloxone were detected in chromaffin cell membranes and in membranes obtained from adrenal medulla homogenates. However, the number of binding sites for [3H]etorphine and [3H]diprenorphine was 10–70 times higher than the number of sites measured with the other 3H ligands. The rank order of potency of these compounds for the displacement of [3H]etorphine binding correlates (r = 0.90) with the rank order of potency of the same compounds for the inhibition of acetylcholine-induced catecholamine release. These data suggest that a stereoselective opiate receptor (different from the classic μ-, δ-, k -, or σ-receptor) with high affinity for etorphine, diprenorphine, β-endorphin, and Met-enkephalin[Arg6,Phe7] modulates the function of the nicotinic receptor in adrenal chromaffin cells. 相似文献