方形黄鼠蚤松江亚种染色体核型分析

本文报道了方形黄鼠蚤松江亚种Citellophilus tesquorum sungaris的染色体核型。该蚤染色体数2n=22,占计数344个细胞的76.7％,可配成11对。性染色体雌蚤为XX,雄蚤为XY。X为中着丝粒染色体,且为全组中最大者;Y为中型近端着丝粒染色体。常染色体以中或亚中着丝粒为主。     

人蛔虫和猪蛔虫染色体核型研究初报

以人蛔虫成虫的睾丸和猪蛔虫成虫的睾丸和卵巢为材料,研究其染色体的核型.结果表明,两种虫的染色体数目均为2n=20,n=10.人蛔虫较大的中型中部着丝粒染色体、中型中部着丝粒染色体、较小型的亚中部着丝粒染色体和较小型端部或亚端部着丝粒染色体各为2、5、1和2个;猪蛔虫则各为1、6、1和2个。根据染色体的相对长度、着丝粒位置可将蛔虫的染色体分为四组.Ⅰ组:人蛔虫为1～2号染色体;猪蛔虫为1号染色体;Ⅱ组:人蛔虫为3～7号染色体;猪蛔虫为2～7号染色体;Ⅲ组:人蛔虫与猪蛔虫均为8号染色体;Ⅳ组:人蛔虫与猪蛔虫均为9～10号染色体.     

印鼠客蚤、人蚤及猫蚤染色体组型及C带、G带的研究

一、材料和方法 上述蚤类的成虫和成熟幼虫。染色体标本制作方法,主要采用短期培养空气干燥法。C、G分带及银染法参考其它昆虫及动物染色体分带技术,略加修改。 二、结果 这三种蚤的核型由5～8对中部或亚中部着丝粒的常染色体和一对端部或亚端部着丝粒的XX/XY的性染色体所组成。每对染色体的相对长度、     

猪巨吻棘头虫染色体核型的初步观察

对猪巨吻棘头虫成虫的卵细胞染色体进行了观察,其染色体为6对(2n=12,n=6)。其中大型中部着丝粒染色体1对,中型中部着丝粒染色体3对,小型亚端着丝粒染色体1对和小型端部着丝粒染色体1对。     

日本血吸虫染色体组型的研究

分析了日本血吸虫的染色体组型,结果表明其染色体数目,2n=16,n=8。核型的组成是:大型染色体4个,中型染色体6个,小型染色体6个,可配成8对。按大小次序排列,第1～5号为亚端部着丝粒染色体,第6～8号为亚中部着丝粒染色体,根据染色体的大小、形态和着丝粒的位置,可将日本血吸虫中国人体株的染色体分为三组:即Ⅰ组(第1～2号染色体),Ⅱ组(3～5号染色体),Ⅲ组(第6～8号染色体)。其中第2号染色体为性染色体。     

广西微小按蚊卵巢营养细胞多线染色体的观察

对广西微小按蚊卵巢营养细胞多线染色体进行观察并绘制了模式图。染色体由5臂组成,X染色体最短,具端着丝粒:Ⅱ号染色体最长,具亚中着丝粒;Ⅲ号染色体具中着丝粒。主要特征区有6区,7A、B,19C,20区,28A,30A、B,37D,38A、B,46D。观察700多张标本,染色体全部呈纯合状态。采用卵巢营养细胞制备的多线染色体带型清晰,伸展良好,染色体的两臂往往相连,易于确定臂间关系。     

两种姬鼠核型研究

本文首次报道高山姬鼠Apodemus chevrieri的染色体核型,2n=48,K.F=6(M)+2(SM)+38(A)+XY(A,ST);中华姬鼠Apodemus draco的染色体核型,2n=48,K.F=46(A)+XY(A,A)。两种均未发现次缢痕和随体。结合业已报道的姬鼠属中12个种及亚种的核型资料,对其亚属和种的分类提供细胞学依据。     

日本血吸虫染色体的初步研究

本文报道日本血吸虫大陆株染色体的数目为2n=16,n=8。其核型分为三组:第一组,1～2号染色体,1号为大的亚端部着丝点。2号为大的亚中部着丝点,系性染色体,雌性为异配性别(ZW):雄性为同配性别(ZZ)。第二组,3～5号染色体,为亚端部着丝点。第三组,6～8号染色体,为亚端部和中部着丝点。日本血吸虫大陆株核型与曼氏血吸虫核型有明显不同,符合亚洲组裂体吸虫表现。     

人工种植体对糖尿病大鼠血糖、血脂的影响

在建立糖尿病（DM）大鼠实验模型基础上,将40只SD雄性大鼠分为空白对照组（A组）、正常种植对照组（B组）、DM对照组（C组）及DM种植组（D组）。各组均分为A1、A2、B1、B2、C1、C2、D1、D2亚组各5只。在B、D组的胫骨近骺端种植纯钛种植体,分别于1、2周后处死A1、B1、C1、D1组及A2、B2、C2、D2组大鼠,并检测各组血糖、血脂变化。结果发现,与A组比较,B、D组甘油三酯降低,低密度脂蛋白胆固醇升高;B组及D2组高密度脂蛋白胆固醇降低;与A2组比较,C2、D2组血糖降低。提示人工种植体可影响DM大鼠的血糖、血脂代谢。     

地塞米松对胶质瘤C6细胞增殖、凋亡的影响

目的 观察地塞米松(Dex)对胶质瘤C6细胞增殖和凋亡的影响.方法 将C6细胞分为A、B、C、D组,每组1.25×106个细胞,A组不加Dex,B、C、D组分别与终浓度为10-5、10-4、10-3 mol/L的Dex共培养;用血计数板计算C6细胞数,用流式细胞仪检测C6细胞周期及凋亡率.结果 培养24 h时,A、B、C、D组C6细胞数依次为4.37×106、4.29×106、3.57×106、3.44 ×106个/瓶,B、C、D组与A组比较,P均＜0.05;C6细胞凋亡率依次为0.37％、0.52％、1.39％、8.24％,D组与A、B、C组比较,P均＜0.05.G0/G1期C6细胞所占比例分别为82.42％、93.21％、93.71％、77.52％,S期分别为13.22％、5.38％、4.06％、14.74％,G2/M期分别为4.36％、1.41％、2.23％、7.74％;B、C组与A组G0/G1、S期细胞比例比较,P均＜0.05;D组与A、B、C组G2/M期细胞比例比较,P均＜0.05.结论 Dex可通过阻滞C6细胞周期进程抑制细胞增殖、诱导细胞凋亡.     

我国红带锥蝽染色体核型及C带分析

目的 对我国红带锥蝽进行核型及C带分析,了解其染色体数目、形态以及C带染色情况.方法 以采自广东顺德的雄性红带锥蝽精巢组织为实验样本,通过滴片法制备中期染色体玻片,进行Giemsa染色和C带染色,显微镜下观察中期染色体形态;同时观察异染色质所在位置,进行显微拍照并记录每条染色体长臂、短臂和全长,分析红带锥蝽染色体核型和...     

人,猪蛔虫在不同发育期和不同时间内染色体结构的研究

采用不同发育期、不同时间制作猪和人蛔虫的染色体，其效果不同。人蛔虫和猪蛔虫的染色体数目均为２ｎ＝２４，ｎ＝１２，其核型由５对大型中部着丝粒染色体，５对中型中部着丝粒染色体和２对小型端部着丝粒染色体组成。雌雄蛔虫未发现有决定性别的异型染色体。     

Cytological Identification of the Chromosome Carrying the IXth Linkage Group (Including H-2) in the House Mouse

Mus poschiavinus x M. musculus hybrids, which had seven metacentric chromosomes derived from the poschiavinus complement, were repeatedly backcrossed to M. musculus and selected for the chromosome carrying the H-2 complex. A line called T1/Klj was established which had one metacentric chromosome. It was shown by linkage tests and by cytogenetic studies that one arm of this metacentric chromosome corresponds to the M. musculus acrocentric chromosome carrying linkage group IX, in which the H-2 complex is found. The distance from the H-2 locus to the centromere was tentatively estimated as 14 map units.     

Cytogenetic studies of the somatic and germ-line cells in sand rats (Psammomys obesus)

Summary The chromosomes in both somatic and germ-line cells of the sand rat (Psammomys obesus) were studied. The diploid number of chromosomes was 48. The autosomes consisted of 4 pairs of large metacentric chromosomes, 10 pairs of medium to small metacentric and submetacentric chromosomes and 9 pairs of telocentric chromosomes. The X chromosomes in both sexes were the largest of the entire complement. The Y chromosome was a mediumsized metacentric chromosome. The two X chromosomes in the female cells were similar in size and morphology but differed in the DNA replication pattern. Studies of the meiotic chromosomes in the male germ-line cells revealed 23 autosome bivalents and the sex chromosomes either as an XY bivalent or X and Y univalents.

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Cytogenetische Studien an somatischen Zellen und solchen der Keimzellreihe bei der Sandratte (Psammomys obesus)

Zusammenfassung — Die Chromosomen von somatischen Zellen und Zellen der Keimzellreihe der Sandratte (Psammomys obesus) wurden untersucht. Die diploide Chromosomenzahl betrug 48. Die Autosomen bestanden aus 4 Paaren großer metazentrischer, 10 Paaren mittlerer bis kleiner metazentrischer und submetazentrischer Chromosomen, und aus 9 Paaren telozentrischer Chromosomen. Bei beiden Geschlechtern waren die X-Chromosomen die größten des ganzen Chromosomensatzes. Das Y-Chromosom war mittelgroß und metazentrisch. Die zwei X-Chromosomen bei Weibchen waren in bezug auf Größe und Morphologie ähnlich, unterschieden sich aber im DNA-Replikationsmuster. Die Chromosomensätze meiotischer Zellen der männlichen Keimzellreihe enthielten 23 bivalente Autosom-Analoge und die Geschlechtschromosomen waren entweder als ein XY bivalent oder als X und Y monovalente vorhanden.

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Etude cytogénétique de cellules somatiques et germinales du rat des sables (Psammomys obesus)

Résumé Les chromosomes des cellules somatiques et germinates ont été étudiés chez le rat des sables (Psammomys obesus). Le nombre diploïde de chromosomes est de 48. Les autosomes consistent en 4 paires de grands chromosomes métacentriques, 10 paires de chromosomes métacentriques et submétacentriques de moyenne ou petite dimension et 9 paires de chromosomes télocentriques. Dans les deux sexes, les chromosomes X sont les chromosomes les plus grands. Le chromosome Y se compose d'un chromosome métacentrique de grandeur moyenne. Les 2 chromosomes X des cellules féminines se ressemblent quant à leur dimension et morphologie, mais diffèrent en ce qui concerne la réplication de l'ADN. L'étude des chromosomes meïotiques provenant des cellules germinales mâles révèle l'existence de 23 autosomes bivalents et des chromosomes sexuels sous forme de XY bivalents ou de X et Y univalents.

     

Effect of statins and aspirin alone and in combination on clinical outcome in dyslipidaemic patients with coronary heart disease. A subgroup analysis of the GREACE study

DECLARATION OF INTEREST: The GREACE study was conducted independently; no Company or Institution has supported it financially. Some of the authors have attended conferences and participated in other trials sponsored by various pharmaceutical companies.We assessed the possible 'synergy' of statins and aspirin (ASA) in reducing vascular events in patients with coronary heart disease, in a post hoc analysis of the GREek Atorvastatin and Coronary-heart-disease Evaluation (GREACE) study. All patients (n = 1600) were divided into four groups according to long-term treatment: Group A (n = 787; statin + ASA), B (n = 93; statin - no ASA), C (n = 599; no statin - on ASA) and D (n = 121; no statin - no ASA). From all patients 692 were either on a statin or ASA monotherapy (Groups B + C). Relative risk reductions (RRRs) in 'all events' (primary endpoint) between groups were assessed. During the 3-year follow-up there were 292 cardiovascular events; 92 (12% of patients) in Group A, 14 (15%) in group B, 144 in Group C (24%) and 42 events in Group D (35%). The total number of events in Group B + C was 158 (23%). The RRRs in the primary endpoint were: Group A versus B 24% (P = 0.1912), A versus C 51% (P < 0.0001), A versus B + C 49% (P < 0.0001) and A versus D 71% (P < 0.0001). The RRRs in Group B versus C was 36% (P = 0.0431) and B versus D 57% (P = 0.0012), while in C versus D 33% (P = 0.0084). Our findings show that statins and ASA have an additive effect in reducing cardiovascular events. Aggressive statin use in the absence of ASA also substantially reduced cardiovascular events. Treatment with ASA in the absence of statin use reduced clinical events in comparison to patients not treated with either drug.     

Y chromosome short arm-Sxr recombination in XSxr/Y males causes deletion of Rbm and XY female sex reversal.

We earlier described three lines of sex-reversed XY female mice deleted for sequences believed close to the testes-determining gene (Sry) on the Y chromosome short arm (Yp). The original sex-reversed females appeared among the offspring of XY males that carried the Yp duplication Sxr on their X chromosome. Earlier cytogenetic observations had suggested that the deletions resulted from asymmetrical meiotic recombination between the Y and the homologous Sxr region, but no direct evidence for this hypothesis was available. We have now analyzed the offspring of XSxr/Y males carrying an evolutionarily divergent Mus musculus domesticus Y chromosome, which permits detection and characterization of such recombination events. This analysis has enabled the derivation of a recombination map of Yp and Sxr, also demonstrating the orientation of Yp with respect to the Y centromere. The mapping data have established that Rbm, the murine homologue of a gene family cloned from the human Y chromosome, lies between Sry and the centromere. Analysis of two additional XY female lines shows that asymmetrical Yp-Sxr recombination leading to XY female sex reversal results in deletion of Rbm sequences. The deletions bring Sry closer to Y centromere, consistent with the hypothesis that position-effect inactivation of Sry is the basis for the sex reversal.     

Variance of signal-averaged electrocardiographic parameters with age in normal children]

The high-frequency components of the surface QRS was analyzed quantitatively in 87 normal infants and children. The subjects were categorized in 4 groups by age; Group A: one day (n = 27), Group B: 1-5 years (n = 20), Group C: 6-10 years (n = 20), Group D: 11-15 years (n = 20), and the results were compared among the 4 groups. Signal-averaging and high-pass, bidirectional and digital filtering were used for analysis. The total duration of the QRS, the duration of the low-amplitude signals (< 40 microV) in the terminal portion of the QRS (U 40), the amplitude of the signals in the QRS (RMS; QRS) and the amplitude of the last 40 msec of the QRS (RMS 40) were measured at high-pass filter frequency settings of 25, 40, 60 and 100 Hz. Statistical analysis was performed with the unpaired t-test. Differences were considered significant if p < 0.05. The results were as follows: 1. At all filters, the durations of the QRS and U 40 were longer in the order of Groups A < B < C < D, and the amplitude of the RMS; QRS and RM 40 were greater in the order of Groups D < C < B < A. 2. There were significant differences in the QRS between the groups at all filters. 3. There were significant differences in U 40 between the groups except between Groups B and C at 25-Hz filter, but at 40-, 60-, 100-Hz filters, there were no significant differences among Groups B, C and D.(ABSTRACT TRUNCATED AT 250 WORDS)