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101.
人工食物对高原鼠兔稳定性碳和氮同位素组成的影响 总被引:6,自引:1,他引:6
以玉米面、小米面和绿豆粉 (质量比为 5∶3∶2 )的混合食物饲喂青藏高原地区特有种高原鼠兔 ,4 0d后断头杀死 ,取其后腿肌肉测定稳定性碳和氮同位素组成。结果表明 ,用混合食物饲喂后 ,高原鼠兔的稳定性碳同位素比值显著升高 ,由对照的 (- 2 4 6 6± 0 2 5 )‰上升为 (- 19 0 5± 0 0 9)‰ ;稳定性氮同位素的组成变化较小 ,仅由对照的 (3 2 8± 0 13)‰增加为饲喂后的 (3 6 1± 0 32 )‰。经人工食物饲喂后 ,高原鼠兔与其食物间稳定性碳同位素的分馏效应为 4 73‰ ,稳定性氮同位素的分馏效应为 2 79‰。C4组分食物的加入影响高原鼠兔的稳定性同位素 (特别是氮同位素 )代谢模式 ,其稳定性同位素代谢周转率可能高于原来预测的 4 0d。 相似文献
102.
An experimental model of mouse embryonic stem cell (ESC) differentiation into cells with contractile activity (similar to that of cardiomyocytes) without embryoid body formation has been obtained. The main factor inducing ESC differentiation along the cardiomyocyte pathway is recombinant cytokine LIF added in the course of long-term culturing. The contractile cells respond positively to treatment with isoproterenol, a cardioactive drug, which is evidence for the presence in these cells of β-adrenoreceptors characteristic of terminally differentiated mammalian cardiomyocytes. 相似文献
103.
R. A. Zinchenko A. Kh. Makaov V. V. Kadyshev V. A. Galkina E. L. Dadali L. K. Mikhailova M. F. Shurygina A. V. Marakhonov N. V. Petrova N. E. Petrina G. I. El’chinonva P. Gundorova A. S. Tanas V. V. Strelnikov A. V. Polyakov E. K. Ginter 《Russian Journal of Genetics》2018,54(7):858-865
The diversity and prevalence of hereditary diseases (HDs) among Nogais of the Karachay-Cherkess Republic (KChR) are described. The size of the surveyed KChR population was 387231 individuals, including 3.81% Nogais (14741 individuals). We revealed 36 nosological forms of HDs (110 patients from 81 families): 22 with autosomal dominant (AD) inheritance, 10 with autosomal recessive (AR) inheritance, and 4 with X-linked inheritance. The prevalence of HDs in Nogais was 1: 134. The features of HD diversity in Nogais were determined in comparison with the previously surveyed populations of Russia. The accumulation of Ehlers–Danlos syndrome (1: 388), AD amelogenesis imperfecta (1: 3685), AD ichthyosis (1: 4914), AR nonsyndromic mental retardation (1: 1340), AR Gilbert syndrome (1: 4914), and X-linked inherited deficit of glucose-6-dehydrogenase (1: 1774 males) was established. The analysis of heterozygous carriage of mutations “major” for Russia in the genes of the four following AR diseases in 118 unrelated clinically healthy Nogais (236 analyzed chromosomes) was performed: cystic fibrosis (13 mutations in the CFTR gene: CFTRdele2,3 (21 kb), F508del, I507del, 1677delTA, 2184insA, 2143delT, 2183AA>G, 2184delA, 394delTT, 3821delT, L138ins, E92K, W1282X); phenylketonuria (six frequent mutations in the PAH gene: R261X, R408W, R413P, F331S, P211T, P211L); nonsyndromic sensorineural hearing loss (35delG mutation in the GJB2 gene); and Gilbert syndrome (an increase in the number of TA repeats in the UGT1A1 gene). Allelic specificity for all studied genes in the Nogai people was revealed. 相似文献
104.
内分泌细胞和神经细胞通过释放激素和神经肽类物质来响应外界刺激,而这些物质的分泌,都是通过致密核心囊泡(dense core vesicle,DCV)来实现的.但是,现阶段关于DCV的生成、转运、释放的机制很大程度上是不清楚的.在本研究中,我们将线虫的排便行为和肠道分泌联系起来,并以此表型进行全基因组RNAi筛选,寻找调节DCV的新基因.我们成功筛选到了一些在肠道调节DCV生成或释放的基因.其中,CAB-1被确认为特异性调节DCV分泌的重要因子.在肠道中,cab-1突变会降低肠道DCV内容物的分泌,而在神经系统中,CAB-1的缺失也会导致DCV的标识物堆积在突触前,而突触囊泡(synaptic vesicle,SV)不受影响. 相似文献
105.
Two endoglucanases (1,4--d-glucan-4-glucanohydrolase, EC 3.2.1.4) were purified to electrophoretic homogeneity from the culture filtrate of a mutant strain Trichoderma sp. M7. The purified endoglucanases had Mr of 57.4 and 55 kDa, and estimated pI values of 4.1 and 3.95/3.75, respectively. Optimal activity for the first cellulase was at pH 4.5 and 50 °C, and at pH 5.5 and 60 °C for the other. Carbodiimide inactivated the one of the purified endoglucanases, while the other was inhibited by iodoacetamide, indicating the involvement of carboxylic or thiol groups in the catalysis. N-Bromsuccinimide strongly inhibited both endoglucanases, suggesting that tryptophan residues are essential for the activity and binding to the substrate. 相似文献
106.
Dynamics of development of the cerebral cortex tissue anlage in 17-day-old embryos of Wistar rats, implanted into the sciatic nerve of mature rats with the aim to establish new relay and trophic centers in the regenerating nerve have been studied. By means of certain morphological methods (silver nitrate impregnation after Bielschowsky-Gros, Sudan black, hematoxylin-eosin, toluidine blue after Nissl stainings) it has been stated that the implanted nerve cells not only preserve their viability, but also differentiate from neuroblasts up to young and mature neurons during 2 months. Already in 14 days after the operation there are blood vessels in the implants; by the 2d month massive myelinization of axons begins in the implant. A part of the regenerating myelin fibers of the nerve gets into the implant and branches. In similar cases connections between the implanted neurons and the host peripheral nervous fibers are supposed to be established. 相似文献
107.
一种快速简便的CaCl2质粒转化方法 总被引:3,自引:0,他引:3
介绍一种质粒DNA快速转化方法.质粒DNA加入感受态细胞,冰浴3~10min,涂布预热至37℃的平板,即可获得与常规转化方法相当的转化效率.操作步骤由5步减至2步,时间由2h减至3~10min.同时探讨了Ca2 浓度、4℃保存时间等因素对感受态细胞转化效率的影响 相似文献
108.
JULES ANGST THOMAS D. MEYER ROLF ADOLFSSON PETER SKEPPAR MAURO CARTA FRANCO BENAZZI RU‐BAND LU YI‐HSUAN WU HAI‐CHEN YANG CHENG‐MEI YUAN PAOLO MORSELLI PETER BRIEGER JUDITH KATZMANN INES ALICE TEIXEIRA LEÃO JOSÉ ALBERTO DEL PORTO DORIS HUPFELD MORENO RICARDO A. MORENO ODEILTON T. SOARES EDUARD VIETA ALEX GAMMA 《World psychiatry》2010,9(1):41-49
This study examined the transcultural robustness of a screening instrument
for hypomania, the Hypomania Checklist-32, first revised version (HCL-32 R1).
It was carried out in 2606 patients from twelve countries in five geographic
regions (Northern, Southern and Eastern Europe, South America and East Asia).
In addition, GAMIAN Europe contributed data from its members. Exploratory
and confirmatory factor analyses were used to examine the transregional stability
of the measurement properties of the HCL-32 R1, including the influence of
sex and age as covariates. Across cultures, a two-factor structure was confirmed:
the first factor (F1) reflected the more positive aspects of hypomania (being
more active, elated, self-confident, and cogni-tively enhanced); the second
factor (F2) reflected the more negative aspects (being irritable, impulsive,
careless, more substance use). The measurement properties of the HCL-32 R1
were largely invariant across cultures. Only few items showed transcultural
differences in their relation to hypomania as measured by the test. F2 was
higher among men and in more severe manic syndromes; F1 was highest in North
and East Europe and lowest in South America. The scores decreased slightly
with age. The frequency of the 32 items showed remarkable similarities across
geographic areas, with two excep-tions: South Europeans had lower symptom
frequencies in general and East Europeans higher rates of substance use. These
findings support the interna-tional applicability of the HCL-32 R1 as a screening
instrument for hypomania. 相似文献
109.
多聚谷氨酰胺(polyglutamine,PolyQ)疾病是由CAG三核苷酸异常重复扩增并编码多聚谷氨酰胺链而致病的一类疾病.目前,已经发现了9种PolyQ疾病,临床表现为成年起病,缓慢进展性的神经系统功能障碍.近年来许多研究者用转基因动物模型(小鼠、果蝇、斑马鱼等)研究神经退行性疾病的表型、发病机制及治疗,其中,果蝇以其独特的分子遗传学优势成为研究PolyQ疾病的理想模式生物.本文就运用转基因果蝇研究PolyQ疾病的表型及发病机制作一综述. 相似文献
110.
c-Abl是非受体酪氨酸激酶,它在细胞内被一些基因毒性的、氧化的及其它形式的压力所激活。目前研究证明:应用标记的c-Abl发现其在细胞内可以相互形成同源二聚体,并且一分子c-Abl的N末端区域与相应的另一分子的C末端相互作用形成二聚体。实验进一步表明: cAbl SH3 结构域结合到另一c-Abl 分子富含脯氨酸的C-末端约958-982氨基酸区域。如果去除c-Abl 富含脯氨酸的结构域,就会阻止二聚体的形成。这些结果首先证实了c-Abl在细胞内可以相互形成同源二聚体,并暗示着二聚体的形成可能影响着c-Abl活性的调节。 相似文献