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1.
Black-shanked douc langurs (Pygathrix nigripes) are Southeast Asian colobines about which primatologists know very little, but they are classed as endangered because of population decline due to habitat loss. Two preliminary studies have shown that this monkey is primarily folivorous, but there are few details of plant selection or seasonal changes in diet. We set out to observe douc langurs directly in the wild to quantify the diet during wet and dry seasons. We confirmed that the species relies on foliage throughout the year, but it includes significant proportions of fruit and flowers in its diet when those items are available. The douc langurs selected various parts from 152 species of plants in 2 national parks, but there did not appear to be favorite species that were heavily selected over others. In both the wet and dry seasons, the black-shanked douc langurs ate mostly leaves, but the diversity of plants consumed increased and the proportion of fruit eaten almost doubled in the wet season. There were diurnal shifts in food selection, but we found no evidence that the douc langurs were foraging strategically to maximize their protein or energy intake.  相似文献   

2.
The effect of the 1;29 Robertsonian translocation on fertility was studied using embryos resulting from matings of nine carrier cows and two carrier bulls. Embryos were collected from the following three mating groups utilizing superovulation: normal bull cross normal cow, normal bull cross translocation carrier cow, and translocation carrier bull cross normal cow. The proportion of ova which were fertilized did not vary among the groups, indicating that fertilization rates were not affected by the translocation. The translocation cows did yield fewer embryos on average than did cows with normal karyotypes, which may suggest ovulation rates are reduced (at least after superovulation attempts) in cattle carrying the 1;29 translocation. Twenty of 39 embryos successfully karyotyped had abnormal chromosome complements. All four of the theoretically predicted karyotypes and two additional abnormal combinations were found. Eight of 39 (20.5%) embryos karyotyped had unbalanced karyotypes which would have resulted in embryonic loss. The proportion of embryos with unbalanced karyotypes, was slightly higher when the cow (36%) carried the translocation than when the bull (19%) did. Results of this study indicate that fertility is impaired due to the presence of this translocation. The major loss in reproductive potential appears to be due to embryonic loss rather than fertilization failure.  相似文献   

3.
We mapped the chromosomal homology of Pygathrix namaeus (douc) with human and other primates by in situ hybridization of human chromosome paints. The synteny of 3 human chromosomes (1, 2, 19) is fragmented in the douc karyotype and the 23 human probes (autosomes plus X) provided 26 signals. There are associations between human chromosomes 14/15, 21/22, and 1/19. Human chromosomes 1 and 19 are divided in two segments and associated on douc chromosomes 8 and 10. The fragmentation and association of human chromosomes 1 and 19 is best explained as the result of a reciprocal translocation, which occurs in all documented Asian colobines studied, but not in the African species Colobus guereza. However, the homologs to douc chromosome 10 in all other Asian documented colobines show an additional pericentric inversion. Our results indicate that Pygathrix nemeus is karyologically the most conservative colobine species yet studied and that this species probably diverged early after the separation of Asian and African Colobinae. The data reinforce the monophyly of the Colobinae and their division into an African and an Asian clade.  相似文献   

4.
优生与遗传咨询的临床研究   总被引:1,自引:0,他引:1  
总结本室优生遗传咨询门诊万例病例资料,应用细胞学方法、荧光原位杂交法和分子遗传学PCR方法检出外周血染色体异常率10.30%(555/5390),产前诊断核型异常率为6.68%(145/2171),胎停育绒毛核型异常率45.16%(28/62),总检出率为9.55%;PCR检测178例,正常人155例,患者23例;FISH结果:性别Y检测5例,21-三体征检测6例,均阳性。传统细胞学方法为染色体病诊断不可替代的重要手段;分子遗传学PCR方法及FISH检测方便、快速、精确,值得推广;遗传咨询,遗传病检测及产前诊断,对降低患儿出生率具有重大意义。 Clinical Research of Genetic Counseling WANG Shu-yu,WANG Su-gui,REN Guo-qing,JIA Chan-wei,MA Yan-min,XUE Hong Capital Medical University Beijing OB/GYN Hospital,Beijing 100006,China Abstract:To supply reliable materials for the assessment of recurrence risk,prenatal diagnosis and the supervision of high risk persons,we analyzed 10811 patients with the methods of cytogenetics,fluorescent in situ hybridization and molecular genetic PCR methods.The result of cytogenetics:there were 555 abnormal karyotypes of peripheral blood on 5390 cases (10.30%);In 2171 patients who asked for prenatal diagnosis,145 abnormal karyotypes were found (6.68%);We also karyotyped chorionic villous cells of 62 patients with spontaneous abortion and found 28 abnormal karyotypes (45.16%).The PCR results of 23 patients with Down's syndrome were all positive while the results of 155 normal persons were all negative.The method of cytogenetics is very important for diagnosis of abnormal karyotypes;Molecular genetic methods by PCR and FISH are quick,convenient and applicable way. Key words:genetic counseling; prenatal diagnosis; karyotypes abnormal; molecular genetics  相似文献   

5.
A method is described that is designed to compare, in a standardized procedure, bivariate flow karyotypes of Hoechst 33258 (HO)/Chromomycin A3 (CA) stained human chromosomes from cells with aberrations with a reference flow karyotype of normal chromosomes. In addition to uniform normalization of normal and abnormal flow karyotypes, the main purpose is detection of structurally abnormal chromosomes in often complex karyotypes of tumor cells. The method, which has been implemented in a computer program, consists of a comparison of individual chromosome peaks with the positions of peaks in the flow karyotype constituted by normal chromosomes and takes into account the natural variability in base composition of normal chromosomes among healthy individuals. Flow-karyotypes are normalized using an iterative fitting procedure, using corrections for (1) amplification of HO and CA fluorescence, (2) cross-talk between the fluorescence signals of HO and CA, and (3) offset of the HO and CA origin. Flow karyotypes of two cell lines, one with a simple deletion and the other with more complex karyotypic changes, were analyzed. The results of flow analysis were found to be in general agreement with the cytogenetic analysis of quinacrine banded karyotypes.  相似文献   

6.
Recent studies at the Endangered Primate Rescue Center (EPRC) in the Socialist Republic of Vietnam's Cuc Phuong National Park by Byron et al. ([2002] Am. J. Phys. Anthropol. [Suppl.] 34:51) and Covert and Byron ([2002] Caring for Primates) revealed unexpected locomotor and postural behaviors in the red-shanked douc langur (Pygathrix nemaeus). This paper further elucidates the question of red-shanked douc suspensory behavior, and provides initial positional behavior data for two other rare Asian colobines, by comparing the ontogenetic positional behavior of red-shanked douc langurs, Delacour's langurs (Trachypithecus delacouri), and Hatinh langurs (Trachypithecus hatinhensis) at the EPRC. Two hundred and seven hours of positional behavior data were collected, with approximately equal amounts of data on each species, and equal amounts on adults and those less than 18 months in age. All young animals were more active than adults, used a wider repertoire of locomotor behaviors, and expressed suspensory behaviors more frequently than did the adults. Young animals also "invented" one new locomotor and two new postural behaviors. These differences are due to both play and explorative behavior, as well as to the youths' changing musculoskeletal systems. The number of positional behaviors utilized by the adults of these species is quite similar to one another (23-32), as is that utilized by the young (51-56). Douc langurs in both age categories used suspensory behaviors more frequently than did Delacour's and Hatinh langurs. Because the uniformity of enclosures offers a control, the results of this study generate hypotheses regarding adaptive radiations and niche partitioning in wild populations.  相似文献   

7.
Summary We have investigated cytogenetically a total of 35 solitary lipomas, 10 of which have been reported previously. Of the 25 tumours presented herein for the first time, clonal chromosome aberrations were detected in 17. The remaining eight had normal karyotypes, although two of them had nonclonal aberrations in about one quarter of the cells. Based on the cytogenetic findings in all 35 lipomas, four major subgroups can be distinguished. These are characterized by: (I) hyperdiploid karyotypes including one or more supernumerary ring chromosomes (5 cases); (II) diploid karyotypes with mostly balanced rearrangements involving 12q13-14 (13 cases), including the rearrangement t(3;12) (q27-28;q13-14) in 4 cases; (III) hypodiploid or diploid karyotypes with other aberrations than ring chromosomes or rearrangements of 12q13-14 (8 cases); and (IV) normal karyotypes (9 cases).  相似文献   

8.
Chromosome analyses were performed on bone marrow of 177 pediatric patients with Acute Lymphocitic Leukemia at the "Hospital Nacional de Nifios". The standard cytogenetic techniques now belongs to the panel of mandatory analyses performed at diagnosis of our acute leukemia patients and represent a major advantage to be effective and independent prognostic factors, essential for therapeutic choices. Cytogenetic results were achieved in 83% of the bone marrow samples: normal karyotypes represented 29% and abnormal karyotypes 71% with the follow distribution: t(9;22) 3%; t(l;19) 5%; t(4;11) 3%, Hyperdiploidy 39%; other chromosomal abnormalities 21%. Systematic cytogenetic analyses are essencial to define morpho-immunologic sub-types of leukemia and to detect new translocations that allows to understand hematopoiesis and leukemogenesis.  相似文献   

9.
A preliminary investigation was made into the meiotic development of oocytes taken from the ovarian follicles of 4–6 week old ewe lambs. In total 1097 oocytes were recovered from 8 lambs of normal karyotype, 5 lambs heterozygous for the Massey 1 Robertsonian translocation and 4 homozygous lambs. After culture 208 oocytes (19%) had resumed meiosis although in only 45 (4.1%) could the behaviour of the chromosomes at metaphase stages I and II be satisfactorily studied. This rather poor recovery was believed to be due to the stage of ovarian development coupled with technical deficiencies.The limited numbers prevent strict conclusions from being drawn but the present findings demonstrated a rather similar chiasma frequency at diakinesis for the three karyotypes (44 ± 3) and hinted that non-disjunction occurs at a higher frequency in the heterozygous female than those with normal or homozygous karyotypes.  相似文献   

10.
Summary This paper summarizes previous chromosomal studies in patients with the Cornelia de Lange syndrome showing abnormal karyotypes. We report on 45 cases of the Cornelia de Lange syndrome clinically examined by one of us (B. B.) and chromosomally studied using several different methods. Two abnormal karyotypes were found: a girl with a 45,X karyotype and a boy with a (13q14q) translocation which was also found in his phenotypically normal mother and maternal grandmother. Because of recent reports of the duplication 3q syndrome and Comelia de Lange-like phenotypes, prometaphase chromosomes were studied in 31 patients. All karyotypes were normal. As there was an excess of boys among the younger patients, special examination for the fragile site on X(q28) was carried out. This abnormality was not found. Even though no patients with the dup(3q) syndrome were found among the Cornelia de Lange patients, chromosome studies are recommended especially in connection with genetic counselling. A recurrence rate of 2–5% must still be considered for the Cornelia de Lange syndrome.  相似文献   

11.
Throughout the world, chromosome alterations are one of the main causes of major malformations in newborns and of multiple clinical characteristics in patients of other ages. The present study had as its principle objective to determine the distribution of chromosome alterations obtained from 1999-2009 at a private laboratory located in Monterrey, Nuevo Leon state, Mexico, and that received samples from other northeastern Mexican states. We studied 1,652 cases of peripheral blood karyotypes. Samples were obtained from patients in whom there was a suspicion of some chromosome alteration based on the clinical history. Of the karyotypes evaluated, 1,250 (76.0%) had normal karyotype, 320 (19.0%) presented chromosome alterations, among which 270 (84%) were numerical, 50 (16%) were structural, and 82 (5.0%) were polymorphisms. Chromosome alteration frequency and type found in the present study is similar to that found in studies conducted in other countries and to that reported in the literature.  相似文献   

12.
Karyotypes of the human C32r16 line and its HPRT-mutant derivatives were compared. All three HPRT-mutant strains (TG-A, TG-E1, and TG-E2) studied were hypotetraploid and arose by genomic duplication. TG-A and TG-E had distinct karyotypes, reflecting their independent clonal origins. Both TG-E1 and TG-E2 were similar karyotypically, except that TG-E2 differed from TG-E1 by the presence of two new sets of balanced translocations and a significantly higher number of new markers, viz., 24 new markers in 14 TG-E2 cells as compared to 2 new markers in 13 TG-E1 cells. Comparison of the hypothetical 2s karyotype of C32r16 with the modal karyotypes of the mutants revealed (1) that chromosome changes occurred more frequently among marker chromosomes (57.1%) than among normal chromosomes (18.1%) and also more frequently among tetrasomic (28.6%) than among disomic (3.3%) normal chromosomes, and (2) that one member of a group of paired marker chromosomes tended to be eliminated very frequently, whereas disomic normal chromosomes retained their disomic condition. Chromosome 7 was involved in the formation of new marker chromosomes twice as much as any other chromosome, and even increased to pentasomy in TG-E1. Chromosome changes associated with 6-thioguanine treatment are briefly discussed.  相似文献   

13.
We report a previously undescribed autosomal reciprocal translocation, t(1;8)(q41;q23.1). It segregates in three families whose common origin lies at least 11 generations back. No examples of unbalanced karyotypes were encountered. Moreover, there was no circumstantial evidence that such live births had occurred during earlier generations. Couples in which one spouse was a translocation carrier were compared to related couples with normal karyotypes. The 15 carrier families had significantly more spontaneous abortions (32%) than the 22 normal couples (10%), irrespective of the sex of the carrier parent. However, the mean number of children was equal in both groups (2.0 and 2.4). Carrier families produced 17 children with a balanced translocation and seven with a normal karyotype. This deviates significantly (P = .04) from the expected 1:1 ratio. We conclude that this malsegregation helps to maintain the translocation in the population. These results show that empirically derived 1:1 segregation ratios previously reported in series that combine many different translocations do not apply to all individual translocations.  相似文献   

14.
We performed chromosomal analysis on 540 mouse embryonic stem (ES) cell lines obtained during 2001 to 2004 from 20 institutions in Japan. Overall, 66.5% of the ES cell lines showed normal chromosomal numbers, but 15.9%, 9.1%, and 2.8% showed modal chromosomal numbers of 41, 42, and 39, respectively. When we karyotyped 88 ES cell lines selected arbitrarily from the 540 lines, 53 (60.2%) showed normal diploid karyotypes; the sex chromosome constitution of 52 lines was XY, with the remaining 1 being XX. Among 35 ES cell lines showing abnormal karyotypes, trisomy of chromosome 8 (41, XY, +8) was dominant (51.4%), 14.3% had trisomy 8 with loss of one sex chromosome (40, XO, +8), and 11.4% had trisomy 8 together with trisomy 11 (42, XY, +8, +11). Karyotypic abnormalities including trisomy 8 and trisomy 11 occurred in 88.6% and 17.1% of ES cell lines, respectively. The XO sex chromosome constitution was observed in 25.7% of all abnormal ES cell lines. Of the 88 selected ES cell lines, 60 lines were established from strain 129 animals, 17 from F1 progeny of C57BL/6J x CBA (called TT2 in this study), and 11 from C57BL/6J mice. Normal diploid karyotypes were observed in 58.3% of lines derived from 129, 58.8% of those from TT2, and 72.7% of C57BL/6J. The relatively high incidence of abnormalities in chromosomal number and karyotype in ES cell lines used in Japan suggests the importance of chromosomal analysis of ES cells for successful establishment of new animal models through germline transmission.  相似文献   

15.
In Asian colobines, small one‐male groups (OMG) seem to predominate alongside all‐male groups (AMG), while larger multimale groups (MMG) are rare, but are reported for Hanuman langurs and red‐shanked douc langurs. Recently, however, it has been speculated that the genus Pygathrix could have multilevel societies based on (1) a theoretical extension of the multilevel societies found in Rhinopithecus to all odd‐nosed colobines and (2) first data for black‐shanked douc langurs. This assumes bands composed of small OMG with a skewed adult sex ratio. Band size may vary with seasonal food availability resulting in smaller bands when feeding competition is increased. To investigate the social organization of red‐shanked douc langurs and potential seasonal influences, we observed 2 unhabituated groups at Hin Namno National Protected Area, Lao PDR from March 2007 to August 2008 for 803 hr. We recorded births and performed group counts and scan sampling of feeding behavior. Most births (79% of N = 15) occurred from June–September, indicating a 4‐month peak conception season from November to February. Group size averaged 24.5 individuals (range 17–45) with 2.45 adult males (range 1–4). Although the smaller group remained at a stable size (about 18 individuals), the larger group reduced from about 45 to 25 individuals during the 7‐months long lean season, when less than 50% of the feeding time was spent on fruits. This suggests feeding competition as a potential cause of seasonal variation in group size. With 1.9 females per male the skew in adult sex ratio was much lower compared with Rhinopithecus, indicating MMG rather than multilevel societies. However, data on the spacing and interaction patterns between recognized individuals need to be collected and analyzed before the social organization can be determined. Detailed ecological data are furthermore required to investigate the basis for the seasonal changes in group size found. Am. J. Primatol. 73:1134–1144, 2011. © 2011 Wiley Periodicals, Inc.  相似文献   

16.
Summary Spontaneous abortions were studied by analyzing chromosomes directly from chorionic villi. The frequency and the type of anomalies detected among 140 abortuses are in good agreement with those observed by others using conventional tissue cultures. Abnormal karyotypes were found in 48.6% of the cases. Trisomy predominated (66.2%), followed by polyploidy (22.1%), monosomy X (7.4%), and structural anomalies (4.4%). Among the trisomies, the most prevalent were of chromosome 22 (22.2%), 16(22.2%), and 13 (9.5%). The relative frequencies of trisomies, monosomy X, and the different chromosomes involved in trisomies seem to differ between our study and those in which tissue cultures were analyzed. Our low frequency of 45,XO karyotypes and the shift to trisomies of chromosomes whose involvement increases steeply with maternal age are considered due to the approximately 3 year higher mean maternal age in our sample. The sex ratio (male to female) in chromosomally abnormal abortuses was 1.28, which is nearly identical to the 1.2 found in earlier studies. Surprisingly, in chromosomally normal abortions males were significantly outnumbered by females (sex ratio 0.76). Since maternal cell contamination cannot have influenced the sex ratio in our study, we consider it worthwhile to investigate whether failures associated with X inactivation are responsible for pregnancy wastage of some euploid female conceptuses. Knowledge of the karyotypes may serve as a prerequisite for the investigation of non-chromosomal genetic causes of pregnancy wastage.  相似文献   

17.
赵晓  沈国民  冯琦  孙晓纲  骆延 《遗传》2008,30(8):996-1002
原发性闭经是一种原因复杂的疾病, 染色体异常则是发病的主要原因。通过对131例原发性闭经患者的外周血淋巴细胞染色体的G带核型分析, 发现其中83例为正常女性核型, 占63.36%; 各种异常核型48例,占36.64%, 其中包括3例世界首次报道的异常核型[46,X,t(X;1)(q22;p34); 46,X,t(X;5;6)(p11.2;q35;q16); 46,XX,t(4; 9)(q21;p22),t(6;10)(p25;q25),t(11;14)(q23;q32)]。另外, 将33例Turner’s综合征患者的主要异常体征及核型分布分别与Elsheikh等的报道进行比较, 发现矮身材、蹼颈、后发迹低和肘外翻的发生率与文献资料存在显著差异, 说明东西方Turner’s综合征患者临床体征的表现可能存在差异。通过对2例X-常染色体易位携带者的分析, 认为Xp11.2和Xq22区域可能与原发性闭经有关。  相似文献   

18.
To assess the relationship between mouse sperm head morphology and karyotype, sperm heads with either a normal or an abnormal morphology were injected individually into enucleated mouse oocytes that were karyotyped at the metaphase of the first cleavage. BALB/c male mice that produce an unusually high proportion of morphologically abnormal spermatozoa were used as sperm donors. Abnormal karyotypes were found in a significantly higher proportion of eggs injected with severely misshapen sperm heads (36-38%) as compared to those injected with normal and quasi-normal heads (15-21%) (p < 0.01). Most karyotype abnormalities were structural rather than numerical, the most common being breaks and exchanges of chromosome type in both normal and abnormal spermatozoa.  相似文献   

19.
In chronic lymphocytic leukaemia the majority of circulating lymphocytes which responded to phytohaemagglutinin in vitro were found to have normal karyotypes. A minor population of cells in patients treated with chemotherapy had an increased number of chromosomal rearrangements as compared with cells from normal controls and untreated patients with chronic lymphocytic leukaemia. Probably bonemarrow and lymph-node cells also had a normal karyotype.In the other lymphoproliferative disorders the peripheral blood lymphocytes had either normal karyotypes or chromosomal abnormalities attributable to treatment, even in those cases where the tumour cells of involved lymph nodes were known to have abnormal karyotypes.It was possible that circulating tumour cells were present in one case.  相似文献   

20.
A new Robertsonian translocation has been found in cattle. A bull from Marchigiana breed (central Italy) was found to be a heterozygous carrier of a centric fusion translocation involving cattle chromosomes 13 and 19 according to RBA-banding and cattle standard nomenclatures. CBC-banding revealed the dicentric nature of this new translocation, underlining the recent origin of this fusion. In fact, both the bull's parents and relatives had normal karyotypes. In vitro fertilization tests were also performed in the bull carrying the new translocation, in two bulls with normal karyotypes (control) and in four other bulls carrying four different translocations.  相似文献   

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