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1.
Genetic differences between trilinear and dilinear forms of a tongue sole, Cynoglossus interruptus, were examined by use of isozymes. Unequivocal differences were detected between the two forms, including complete replacement of alleles at the FBALD-2*, MDH-3*, PROT-1*, and SOD-1* loci, almost complete replacement at the AAT-3*, AH-1*, AH-2*, EST-3*, G3PDH-3*, GPI-2*, IDHP-1*, and MDH-1* loci, and extreme differences in allelic frequencies at the GPI-1* and PGDH* loci. The genetic distances (D values) between the two forms were 0.4207–0.4353, figures predicatively significant at the specific level. The considerable genetic differences strongly suggested that the two forms represent distinct species. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

2.
Summary Malaysians of Malay, Chinese, and Indian ancestries were electrophoretically phenotyped for Amy1 and saliva esterase region 1(Set-1) from saliva, Amy2 from plasma, soluble and mitochondrial GOT and PGM 3 from leukocyte and placenta. Kadazans and Bajaus, the indigenous people of Sabah, East Malaysia were surveyed for Amy2. Three types of variants were observed for Amy1, one type for Amy2. Only Indians were found to be polymorphic for Amy1. Two GOT s 2-1 and three GOT m 2-1 variants were found among 281 Chinese while three GOT m 2-1 variants were found among 311 Malays.Malaysian Malays, Chinese, and Indians were found to be polymorphic for Set-1 and PGM 3. The gene frequencies in Malays are Set-1F=0.601±0.021, Set-1S=0.399±0.021; PGM 3 1 =0.788±0.020, PGM 3 2 =0.212±0.020; in Chinese Set-1F=0.497±0.028, Set-1S=0.503±0.028; PGM 3 1 =0.745±0.024, PGM 3 2 =0.255±0.024; in Indians, Set-1F=0.449±0.031, Set-1S=0.551±0.031; PGM 3 1 =0.755±0.029, PGM 3 2 =0.245±0.029.  相似文献   

3.
Allozyme electrophoresis was used to assess temporal genetic variation in three successive generations of the Mediterranean killifish, Aphanius fasciatus. Samplings were carried out in 1995, 1996 and 1997 in a brackish-water habitat at Elba Island, Italy and a total of 212 specimens were collected. The five loci for which polymorphism has been detected in a previous study were assayed. Mean expected heterozygosity values [H=0.397 (SE 0.077), H=0.336 (SE 0.092) and H=0.313 (SE 0.092) in 1995, 1996 and 1997, respectively] were not significantly different by ANOVA test. Deviations from Hardy–Weinberg equilibrium were minimal, with only one out of the 15 probability tests showing a significant departure from the equilibrium; whereas genotypic linkage disequilibrium was not detected. Values of Nei's genetic distance were lower than 0.04. Temporal genetic variation in the A. fasciatus population at Elba Island was observed, with F-statistics indicating significant genetic divergence among samples (=0.035, SE 0.027, p<0.001). Genetic drift acting on two loci (GPD-1 * and LDH-3 *) is presumably the main force determining the temporal genetic heterogeneity observed; however, the occurrence of selection on individual loci and/or sampling error cannot be excluded. The observed allelic variation among generations in a single population of A. fasciatus is much less than levels observed among geographically discrete samples in previous studies.  相似文献   

4.
Heterozygosity at nine genetic loci (PI, TF, PGM1, ACP1, HP, GC, GLO1, C3, and ESD) was analyzed in pulmonary tuberculosis patients with good (group 1, N= 71) and poor (group 2, N= 35) response to treatment. The observed heterozygosities were compared with the expected values, which were calculated from allele frequencies in a control sample of healthy individuals (N= 328 with all but one locus and 78 with ESD) according to Hardy–Weinberg expectations. The analysis showed that the observed heterozygosities g l of patients significantly differed from the expected values h lin the case of four loci (GC, PI, C3, and ACP1). The observed heterozygosity was higher than expected in three cases (PI, C3, and ACP1) and lower then expected (GC) in one case. When data on each individual locus were compared using Fisher's exact test, both groups of patients proved to significantly differ (P F< 0.05) from the control group in the same four loci. No difference in observed heterozygosity was detected between the two groups of patients. The mean expected heterozygosity was h¯= 0.386 ± 0.00674; the mean observed heterozygosity was g¯ = 0.415 ± 0.02 in group 1, g¯ = 0.402 ± 0.026 in group 2, and g¯ = 0.371 ± 0.00955 in the control group. The ttest did not reveal a significant difference between the mean values of expected observed heterozygosities. Heterozygosity at individual loci, rather than mean heterozygosity, was proposed as an integral nonspecific indicator of the genetic control of a disease, because the former directly implicates individual marker loci in the development of a disorder, whereas effects of individual loci may eliminate each other when mean heterozygosity is computed. Based on the results obtained, a genetic control was assumed for the development of the tuberculosis process in the lungs.  相似文献   

5.
Summary Phosphoglucomutase1 (PGM1) polymorphism was studied in a French-Canadian population of Québec city, Canada by means of a low voltage (max 500 V) isoelectric focusing (IEF) procedure on vertical polyacrylamide gel slabs. Frequencies of the four common PGM1 genes estimated from the phenotype distribution in 308 unrelated individuals were PGM 1 1+ , 0.61 (±0.02); PGM 1 1- , 0.13 (±0.01); PGM 1 1+ , 0.61 (±0.02); PGM 1 1- , 0.18 (±0.02); and PGM 1 1+ , 0.61 (±0.02); PGM 1 1- , 0.08 (±0.01). The segregation patterns observed in 154 families, which included 31 different mating types and 353 children, confirmed a Mendelian inheritance of four autosomal genes. The distribution of the PGM1 phenotypes observed or expected in a Hardy-Weinberg equilibrium was compared with that of other populations. A significant (P<0.001) difference was found between the Québec population and a Black population from Keneba, Gambia, West-Africa.  相似文献   

6.
An analysis of 28 enzyme loci throughout developmental stages ofSepedon fuscipennis fuscipennis Loew indicated that 16 were polymorphic and 4 were monomorphic in all stages. Nine loci were differentially expressed among the stages: EST-1, EST-2, MDH-2, MDH-3 and PGI-1 occurred only in larvae, AK-3 mainly in pupae, and AK-1, AO and HK-1 only in adults. The average heterozygosity ofS. f. fuscipennis was 0.146 (±0.028) across all stages.   相似文献   

7.
Galego LG  Ceron CR  Carareto CM 《Genetica》2006,126(1-2):89-99
The aim of this study was to characterize esterases in Zaprionus indianus, a drosophilid recently introduced into Brazil. A further aim was study the variation of activity of esterases in the presence of inhibitors and their expression according to sex, sexual activity and age of individual flies. Polymorphisms were detected in two esterase loci (Est-2 and Est-3) and monomorphisms in four others (Est-1, Est-4, Est-5 and Est-6). Biochemical tests using α- and β-naphthyl acetate and the inhibitors malathion, eserine sulphate and PMSF allowed us to classify EST-2 and EST-5 as β-esterases, both carboxyl-esterases, and EST-1, EST-3, EST-4 and EST-6 as α-esterases. EST-1 and EST-3 were classified as carboxyl-esterases and EST-4 and EST-6 as cholinesterases. EST-5 activity was more pronounced in males and EST-2 was restricted to them or to recently copulated females. EST-4, rarely detected, was not characterized. Based on their biochemical characteristics possible roles for these enzymes are suggested.  相似文献   

8.
Genetic polymorphism of human urine deoxyribonuclease I   总被引:7,自引:2,他引:5  
Summary A genetic polymorphism of human urine deoxyribonuclease I (DNase I) has been detected by the technique of polyacrylamide gel isoelectric focusing (IEF-PAGE) followed by immunoblotting with anti-DNase I antibody. Family studies showed that the three common phenotypes —DNASE1 1, 1–2, and 2 — and the other four rare phenotypes — DNASE1 1–3, 2–3, 2–4, and 3–4 — represent homozygosity or heterozygosity for four autosomal codominant alleles, DNASE1 * 1, * 2, * 3, and * 4. The frequencies of the DNASE1 * 1, DNASE1 * 2, DNASE1 * 3, and DNASE1 * 4 alleles in a studied Japanese population were 0.5453, 0.4396, 0.0117, and 0.0034, respectively.  相似文献   

9.
Analysis of the blood protein system was used to study the genetic composition of Arabian horses. Biochemical markers of eight polymorphic loci (Tf, Al, As, AlB, Gc, Hb, PGD, and PGM) were electrophoretically identified in blood samples. A total of 43 phenotypes were identified for these polymorphic systems. The Tf, Hb, and Esloci appeared to be more polymorphic than the other loci studied. Statistically significant differences between the observed and expected genotypic frequencies were found for the PGDandPGMloci (P< 0.05 and P< 0.01, respectively). Individual allele frequencies, observed and expected phenotype frequencies, and the average heterozygosity were estimated for each polymorphic locus.  相似文献   

10.
This study presents the first protein electrophoretic study of population structure within the Georgia Basin Pacific hake Distinct Population Segment, as defined under the U.S. Endangered Species Act. Forty-one allozyme loci (29 polymorphic) were analyzed in samples from three Pacific hake spawning populations on the west coast of North America: (1) Port Susan, Puget Sound, Washington (three temporal samples); (2) south-central Strait of Georgia, British Columbia, Canada (two temporal samples); and (3) offshore of southern California (two temporal samples) (total n = 664). Mean heterozygosity over all loci was 12–13% for all populations. Within-population temporal samples were not significantly different from one another, but statistically significant differences were detected at 15 of the 29 polymorphic loci (p < 0.05) among the three populations. Differences at eight of these loci were highly significant (p < 0.001): ADA *, ALAT *, bGALA *, GPI-A *, sIDHP *, LDH-A *, MPI *, and PEP-B *. The two Georgia Basin populations were significantly different at six loci: bGALA *, sIDHP *, LDH-A *, MPI *, PGK *, and PGM-2 * (p < 0.05). Nei's genetic distance (D) was 0.0006 between Port Susan and Strait of Georgia pooled temporal samples, and 0.005 between these populations and offshore Pacific hake. FST was 0.02 and 0.0046 among all three populations and among the Georgia Basin populations, respectively. Both FST estimates were significantly greater than zero, and the results suggest a high degree of demographic isolation among all three populations.  相似文献   

11.
We examined allozymic variation in 65 protein-coding loci in three samples of sockeye salmon (Oncorhynchus nerka) from Hokkaide, and Honshu, Japan, Over-all, six variable loci were seen and each of the three samples was variable at 3–5 loci. Two loci,mAH-1,2 * andALAT *, were variable at the P0,95 level. Average heterozygosity ranged from 0.012 to 0.013, representing some of the lowest recorded values for the species. Although frequencies ofALAT * alleles differed significantly among the three samples, the overallχ 2 for six polymorphic loci was not statistically significant. New data for four Russian samples at 45–64 loci were also obtained. In comparison to the Japanese samples, three samples from the Kamchatka Peninsula had two to three times the level of variation; and a sample from Iturup Island (Kuril Island archipelago) was slightly more variable. Although the anadromous sockeye salmon were originally planted from Iturup Island to Lake Shikotsu, a close genetic affinity was not indicated. These seven samples ofO. nerka were compared with representative samples previously studied in North America using five polymorphic loci. Two large groups of samples were indicated in multilocus analyses: 1) a cluster of the seven Asian samples, one Alaskan sample, and one northern British Columbia sample; and 2) a group that included a southern British Columbia sample (Fraser River), and samples from the Columbia River and Washington. We discuss these findings in light of maintaining viable populations of both forms ofO. nerka.  相似文献   

12.
Polymorphic analysis of human phosphoglucomutase-3 (PGM3) has been carried out from the level of the gene product. Due to a weak zymogram, leading to ambiguity in phenotyping, information on the PGM 3 locus has rarely been reported. In this study, the missense mutation G1396A, confirmed to underlie common phenotypes of PGM3, was identified by performing mismatched PCR–RFLP. Population data on the PGM 3 locus was also obtained for the first time in China. The allele frequency distribution was PGM 3 *1 = 0.625, PGM 3 * 2 = 0.375, and no deviation from Hardy–Weinberg equilibrium was observed. The application of the information in both genetics and forensic medicine demonstrated that the polymorphism information content was 0.5163, heterozygosity 0.4872, power of discrimination 0.5986, and probability of paternity exclusion 0.1794. Polymorphic analysis of the locus at the DNA level will also provide significant data for disease susceptibility and linkage analysis.  相似文献   

13.
The genetic population structure of the Japanese freshwater goby Gymnogobius castaneus was investigated on the basis of analysis of gene products of 19 allozyme loci. Two diverged groups were detected, one being endemic to the Kanto region and the other extensively distributed in eastern Japan. These two groups were distinguishable from each other by a complete allelic substitution in one locus, G3PDH*. In the Kanto region, both groups were distributed in the same river basin, being distinguishable by a complete allelic substitution in four loci, G3PDH*, GPI-2*, PGDH*, and PGM*. These results suggest that these two groups showed reproductive isolation.  相似文献   

14.
Minor histocompatibility (H) loci are significant tissue transplantation barriers but are poorly understood at the genetic and molecular level. We describe the construction of a high-resolution genetic map that positions a class II MHC-restricted minor H antigen locus and orders 12 other genes and genetic markers within the we-un interval of mouse Chromosome (Chr) 2. An intersubspecific backcross between 10.UW/Sn-H-3 b and CAST/Ei, an inbred stock of Mus musculus castaneus, was used for this purpose. A total of 1168 backcross mice were generated, and 71 we-un recombinants were identified. Significant compression of the genetic map in males versus females and transmission distortion of CAST-derived we, un, and A w genes were observed. Monoclonal T cell lines specific for two minor H alloantigens, Hd-1a and Hd2a, encoded by gene(s) that map to the we-un interval were used to antigen type the backcross mice. The results suggest the Hd-1a and Hd-2a antigens are most likely encoded by a single gene, now referred to as H-3b. The determined gene order is we-0.09±0.09-Itp-0.62±0.23-D2Mit77-0.26±0.15[Evi-4, Pcna, Prn-p]-0.26±0.15-Scg-1-0.44±0.19-[Bmp2a, D2Mit70]-0.09±0.09-[D2Mit19, D2Mit46]-1.59±0.36-D2Mit28-0.97±0.28-D2Lerl-1.50±0.35-H-3b-0.26±0.15-un (% recombination±1 SE). Because the average resolution of the backcross is 0.09 cM, the backcross panel should facilitate the physical mapping and molecular identification of a number of genes in this chromosome region.  相似文献   

15.
The study continues the series of works on the Russian gene pool. Gene geographic analysis of five erythrocytic gene markers best studied in the Russian population (ACP1, PGM1, ESD, GLO1, and6-PGD) has been performed. Gene-geographic electronic maps have been constructed for 13 alleles of these loci and their correlations with geographic latitude and longitude. For all maps, statistical characteristics are presented, including the variation range and mean gene frequencies, partial and multiple correlations with latitude and longitude, and parameters of heterozygosity and interpopulation diversity. The maps of eight alleles (ACP1*A, ACP1*C, PGM1*2+, PGM1*2–, PGM1*1–, ESD*1, GLO1*1, and PGD*C) are shown and analyzed in detail. The genetic relief and structural elements of the maps are compared with the ecumenical trends, main variation patterns of these genes in northern Eurasia, and genetic characteristics of the indigenous populations of the Urals and Europe.  相似文献   

16.
Genetic Mapping in Xenopus Laevis: Eight Linkage Groups Established   总被引:5,自引:1,他引:4  
J. D. Graf 《Genetics》1989,123(2):389-398
Inheritance of alleles at 29 electrophoretically detected protein loci and one pigment locus (albinism) was analyzed in Xenopus laevis by backcrossing multiply heterozygous individuals generated by intersubspecies hybridization. Pairwise linkage tests revealed eight classical linkage groups. These groups have been provisionally numbered from 1 to 8 in an arbitrarily chosen order. Linkage group 1 includes ALB-2 (albumin), ADH-1 (alcohol dehydrogenase), NP (nucleoside phosphorylase), and ap (periodic albinism). Linkage group 2 contains ALB-1 and ADH-2, and probably is homeologous to group 1. Linkage group 3 comprises PEP-B (peptidase B), MPI-1 (mannosephosphate isomerase), SORD (sorbitol dehydrogenase), and mIDH-2 (mitochondrial isocitrate dehydrogenase). Linkage group 4 contains GPI-1 (glucosephosphate isomerase) and EST-4 (esterase 4). Linkage group 5 contains GPI-2 and PEP-D (peptidase D). Linkage group 6 comprises ACP-3 (acid phosphatase), sME (cytosolic malic enzyme), and GLO-2 (glyoxalase). Linkage group 7 consists of sSOD-1 (cytosolic superoxide dismutase), GPD-2 (glycerol-3-phosphate dehydrogenase), mME (mitochondrial malic enzyme), and the sex determining locus. Linkage group 8 includes FH (fumarate hydratase) and TRF (transferrin). Recombination frequencies between linked loci showed differences related to the genomic constitution (parental subspecies) and to the sex of the heterozygous parent. Independent assortment was observed between the duplicate ALB loci. This is true for the duplicate ADH, GLO, and MPI loci as well, supporting the view that these genes have been duplicated as part of a genome duplication that occurred in the evolutionary history of X. laevis. Comparative analysis of genetic maps reveals a possible conservation of several linkages from the Xenopus genome to the human genome.  相似文献   

17.
Summary The red cell enzymes acid phosphatase, adenylate kinase, adenosine deaminase and phosphoglucomutase were analyzed by horizontal starch gel electrophoresis in 43 members of the family Pongidae: Pongo pygmaeus (n=10), Gorilla g. gorilla (n=8), Pan troglodytes (n=22) and Pan paniscus (n=3).In all the Pongidae a red cell acid phosphatase zymogram corresponding to the phenotype B in man was found. The adenylate kinase corresponded to the human phenotype AK 1. All the Pongidae showed the same homozygous adenosine deaminase phenotype which was different from the zymograms in man and was designated ADA ape. In all Pongidae the allele PGM 1 1 was present, in addition in Gorilla g. gorilla a second allele was demonstrated, PGM 1 Go . In Pan troglodytes a second allele, PGM 1 Pan was recognized. In Pongo pygmaeus and Gorilla g. gorilla the PGM2 patterns differed in their migration rates from PGM2 1 in man. In one individual of the species Pan troglodytes a PGM2 zymogram was found resembling the heterozygous phenotype PGM2 3–1, PGM 2 1 PGM 2 3, (type Palmer) in man. In all the other individuals of the species Pan troglodytes and in those of the species Pan paniscus the PGM2 zymogram corresponded to the phenotype PGM2 1 in man.
Zusammenfassung Bei 43 Vertretern der Familie Pongidae, Pongo pygmaeus (n=10), Gorilla g. gorilla (n=8), Pan troglodytes (n=22) und Pan paniscus (n=3), wurden die Erythrocytenenzyme saure Phosphatase, Adenylatkinase, Adenosindeaminase und Phosphoglucomutase mit der horizontalen Stärkegelelektrophorese analysiert. Bei allen Pongiden fanden wir eine saure Phosphatase, die dem Phänotyp B des Menschen entsprach, und eine Adenylatkinase, die dem Phänotyp AK 1 des Menschen glich. Alle Pongiden besaßen das gleiche, einem homozygoten Phänotyp entsprechende Adenosindeaminase-Zymogramm, das sich von den Zymogrammen des Menschen unterschied; wir bezeichnen diesen Phänotyp mit ADA ape. Bei allen Pongiden kommt das Allel PGM 1 1 vor, bei Gorilla g. gorilla zusätzlich ein zweites Allel, PGM 1 Go , und bei Pan troglodytes ein zweites Allel, PGM 1 Pan . Die PGM2-Zymogramme von Pongo pygmaeus und Gorilla g. gorilla unterschieden sich in ihrer elektrophoretischen Wandergeschwindigkeit vom Phänotyp PGM2 1 des Menschen. Bei einem Individuum der Species Pan troglodytes fanden wir ein heterozygotes PGM2-Zymogramm, das an den heterozygoten Phänotyp PGM2 3–1, PGM 2 1 PGM 2 3 (Typ Palmer) des Menschen erinnerte, bei allen übrigen Individuen der Species Pan troglodytes und bei denen der Species Pan paniscus ein homozygotes PGM2-Zymogramm, das dem Phänotyp PGM2 1 des Menschen entsprach.


Supported by the Deutsche Forschungsgemeinschaft.  相似文献   

18.
This study calculated the compositional nutrient diagnosis (CND) norms of cowpea (Vigna unguiculata (L.) Walp.), as well as identified significant nutrient interactions of this crop growing in an irrigated calcareous desert soil. Three genotypes were distributed in rows in a 2-ha field. The soil showed high heterogeneity in its chemical properties. For statistical analysis, 86 foliar composite samples from healthy plants were used. Preliminary CND norms were developed using a cumulative variance ratio function and the 2 distribution function. Means and standard deviations of row-centered log ratios VX of five nutrients (N, P, K, Ca, and Mg) and a filling value R, which included all nutrients not chemically analyzed. Preliminary CND norms are: VN*=0.174±0.095, VP*=–2.172±0.234, VK*=–0.007±0.267, VCa*=–0.022±0.146, VMg*=–1.710±0.132, and VR5*=3.728±0.084. These CND norms are associated with dry bean yields higher than 1.88 t ha–1, and are associated with the following foliar concentrations: 26.2 g N kg–1, 2.5 g P kg–1, 22.9 g K kg–1, 21.6 g Ca kg–1, and 4 g Mg kg–1. Cowpea plants growing in desert calcareous soils took up lower amounts of N, P, and K than those considered as optimum in a previous report. Six interactions were strongly indicated for cowpea through principal component analyses: positive for Ca–Mg, and negative for N–Ca, N–Mg, Ca–P, Mg–P, and K–P. Furthermore, two interactions were identified using simple correlations, negative N–P and positive K–Ca.  相似文献   

19.
Summary This study was conducted to assess the genetic basis of the variability observed for the glutamate oxaloacetate transaminase (GOT), Superoxide dismutase (SOD), esterase (EST), and malate dehydrogenase (MDH) isozyme systems in different open-pollinated Vicia faba varieties. Individual plants showing contrasting zymogram patterns were simultaneously selfed and cross-combined. Crossing was unsuccessful in producing progeny, and only selfed progenies were suitable for genetical analysis of isozyme variability. Three zones of GOT activity were made visible. The isozyme of GOT-2 and GOT-3 zones were dimeric and under the control of three alleles at the Got-2 locus and two alleles at the Got-3 locus, respectively. The isozymes of the GOT-1 zone did not show any variability. Three zones of SOD isozyme activity were made visible. The isozymes occurring in the SOD-1 (chloroplastic isozyme form) and SOD-2 (cytosol isozyme form) zones were dimeric and under the control of two alleles at the Sod-1 and Sod-2 loci. The isozyme visualized in the SOD-3 zone (mitochondrial isozyme form) were tetrameric and under the control of two alleles at the Sod-3 locus. Apparently the isozymes made visible in the most anodal esterase zones EST-1, EST-2, and EST-3 were monomeric, and the occurrence of two alleles at each of two different loci explained the variability observed in the EST-2 and EST-3 zones. For MDH, only two five-banded zymogram pattern types were found, and every selfed progeny showed only one of the two zymogram type, indicating that each individual possessed fixed alleles at the loci controlling MDH isozyme. Got-2, Got-3, Sod-1, Sod-2, and Sod-3 appear to be five new isozyme gene markers that can be useful in Vicia faba breeding for linkage study, varietal fingerprinting, outcrossing rate estimate, and indirect selection for quantitative characters.  相似文献   

20.
The effects of various metabolites on the two most common phosphoglucomutase allozymes (PGMA and PGMB) in Drosophila melanogaster have been investigated in vitro. 2,3-Diphosphoglycerate (2,3DPG) inhibited PGMA and PGMB to the same degree in the presence of 25 µM glucose-1,6-diphosphate (G1, 6P2). However a higher concentration of G1,6P2 partially reversed the inhibition of PGMA exerted by 2,3DPG, so that in the presence of 150 µM G1,6P2 the inhibition of PGMA was half that of PGMB at pH 6.0. Glycerol-3-phosphate (G3P) had no significant effect at pH 7.4 but exerted an activating effect at pH 6.0 which was more pronounced in the case of PGMB. ATP, citrate, and fructose-1, 6-diphosphate (F1,6P2) inhibited both PGMA and PGMB. The differences found in vitro between these two allozymes can have a significant impact on in vivo function and, therefore, on the maintenance of PGM polymorphism in experimental populations of D. melanogaster studied in the laboratory.  相似文献   

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