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101.
102.
Phylogeography of Y-chromosome haplogroup I reveals distinct domains of prehistoric gene flow in europe 总被引:12,自引:2,他引:12 下载免费PDF全文
Rootsi S Magri C Kivisild T Benuzzi G Help H Bermisheva M Kutuev I Barać L Pericić M Balanovsky O Pshenichnov A Dion D Grobei M Zhivotovsky LA Battaglia V Achilli A Al-Zahery N Parik J King R Cinnioğlu C Khusnutdinova E Rudan P Balanovska E Scheffrahn W Simonescu M Brehm A Goncalves R Rosa A Moisan JP Chaventre A Ferak V Füredi S Oefner PJ Shen P Beckman L Mikerezi I Terzić R Primorac D Cambon-Thomsen A Krumina A Torroni A Underhill PA Santachiara-Benerecetti AS Villems R Semino O 《American journal of human genetics》2004,75(1):128-137
To investigate which aspects of contemporary human Y-chromosome variation in Europe are characteristic of primary colonization, late-glacial expansions from refuge areas, Neolithic dispersals, or more recent events of gene flow, we have analyzed, in detail, haplogroup I (Hg I), the only major clade of the Y phylogeny that is widespread over Europe but virtually absent elsewhere. The analysis of 1,104 Hg I Y chromosomes, which were identified in the survey of 7,574 males from 60 population samples, revealed several subclades with distinct geographic distributions. Subclade I1a accounts for most of Hg I in Scandinavia, with a rapidly decreasing frequency toward both the East European Plain and the Atlantic fringe, but microsatellite diversity reveals that France could be the source region of the early spread of both I1a and the less common I1c. Also, I1b*, which extends from the eastern Adriatic to eastern Europe and declines noticeably toward the southern Balkans and abruptly toward the periphery of northern Italy, probably diffused after the Last Glacial Maximum from a homeland in eastern Europe or the Balkans. In contrast, I1b2 most likely arose in southern France/Iberia. Similarly to the other subclades, it underwent a postglacial expansion and marked the human colonization of Sardinia ~9,000 years ago. 相似文献
103.
The role of macrophages acting as immunologic antitumor effectors and promoters of tumor growth are poorly understood as yet. We investigated the role of macrophage in model of concomitant immunity (CI), a phenomenon of secondary tumor rejection during the primary tumor growth. It has been shown that the period of CI weakening can coincide with appearance of tumor metastases. We used mammary carcinoma (MC) artificial lung metastases to evaluate the influence of macrophages from various period of CI on the development of metastases in mice. Our results indicated that macrophages are responsible for the late period of CI weakening and suppression. To investigate weather prostaglandins can mediate suppressive effect of macrophages we used experiments with indomethacin and we found that inhibition of prostaglandin E2 synthesis by indomethacin restored antimetastatic effect of concomitant immune macrophages. 相似文献
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Vaughn MW Tanurdzić M Lippman Z Jiang H Carrasquillo R Rabinowicz PD Dedhia N McCombie WR Agier N Bulski A Colot V Doerge RW Martienssen RA 《PLoS biology》2007,5(7):e174
Cytosine methylation of repetitive sequences is widespread in plant genomes, occurring in both symmetric (CpG and CpNpG) as well as asymmetric sequence contexts. We used the methylation-dependent restriction enzyme McrBC to profile methylated DNA using tiling microarrays of Arabidopsis Chromosome 4 in two distinct ecotypes, Columbia and Landsberg erecta. We also used comparative genome hybridization to profile copy number polymorphisms. Repeated sequences and transposable elements (TEs), especially long terminal repeat retrotransposons, are densely methylated, but one third of genes also have low but detectable methylation in their transcribed regions. While TEs are almost always methylated, genic methylation is highly polymorphic, with half of all methylated genes being methylated in only one of the two ecotypes. A survey of loci in 96 Arabidopsis accessions revealed a similar degree of methylation polymorphism. Within-gene methylation is heritable, but is lost at a high frequency in segregating F2 families. Promoter methylation is rare, and gene expression is not generally affected by differences in DNA methylation. Small interfering RNA are preferentially associated with methylated TEs, but not with methylated genes, indicating that most genic methylation is not guided by small interfering RNA. This may account for the instability of gene methylation, if occasional failure of maintenance methylation cannot be restored by other means. 相似文献
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Attachment is a point of interest in psychosomatic research since it influences a wide array of biopsychosocial phenomena. Data from literature highlights the role of this concept in the context of Inflammatory Bowel disease (IBD), still, there is a lack of data regarding attachment among parents of children with chronic gastrointestinal diseases. The main hypothesis for the current study is that parents of children with IBD will have a more insecure attachment than parents of children with celiac disease (CD) and parents of healthy children. The second hypothesis is that insecure attachment among parents of sick children will be associated with lower parental quality of life (QoL). 46 parents of children with IBD, 42 parents of children with CD and 43 parents of healthy children completed the validated modification of the Brennan's Experiences in Close Relationship Inventory. Results were categorized as secure and insecure attachment. In order to assess parental QoL, the WHOQOL-BREF questionnaire was used. The Total QoL was calculated as a sum of all domain items. Secure attachment was found in 45.7% parents of children with IBD, in 35.7% parents of children with CD and in 32.6% parents of healthy children. Surprisingly, the lowest rate of secure attachment was found in parents of healthy children. However, significant differences among groups do not exist. For all groups of parents the attachment style is associated with Total QoL, although only among parents of children with IBD, the secure attachment independently and significantly predicts higher parental Total QoL. According to results, we might say that parental attachment style does not have a role that exclusively belongs in the context of paediatric chronic gastrointestinal diseases. However, parents of children with IBD who have insecure attachment represent target group for psychosocial support in order to improve their QoL. 相似文献
109.
Igić R Wania-Galicia L Jackman HL 《Canadian journal of physiology and pharmacology》2001,79(7):627-630
We investigated the degradation of angiotensin I (Ang I) by guinea pig aqueous humor at physiological pH (pH 7.4) and assessed the activity of responsible enzymes using various enzyme inhibitors. The aqueous humor was incubated with Ang I in the presence or absence of an enzyme inhibitor at 37 degrees C for the appropriate time period. The resulting peptides were analyzed by a Beckman HPLC system with a Waters microBondapak C18 analytical column using a 30-min increasing linear gradient of 10 to 40% acetonitrile containing 0.05% trifluoroacetic acid (TFA) and H2O containing 0.05% TFA at a flow rate of 1 mL/min. Detection was done by absorbance at 214 nm. Angiotensin II (Ang II) was a major product (39.3+/-4.10 nmol x h(-1) mL(-1), n = 5) of Ang I hydrolysis. Traces of angiotensin 1-9, angiotensin IV, and angiotensin 1-7 were also produced. Chymostatin (0.05 mmol/L), EDTA (1 mmol/L), enalaprilat (0.1 mmol/L), and ebelacton B (0.01 mmol/L) inhibited generation of Ang II from Ang I by guinea pig aqueous humor by 89+/-4.6, 56+/-7.6, 33+/-5.1, 20+/-6.5%, respectively. Our findings indicate that guinea pig aqueous humor contains several enzymes that can form Ang II. The chymostatin-sensitive type of enzyme was the most active one found in guinea pig aqueous humor. Angiotensin I converting enzyme, carboxypeptidase A, and deamidase may also contribute to angiotensin II formation in guinea pig ocular fluid. 相似文献
110.
Platelet serotonin (5-HT) concentration was measured in 65 male and 45 female chronic renal patients on hemodialysis (HD) with different somatic symptoms of depression (crying spells, irritability, sleep disturbance, fatigability, loss of appetite, weight loss, somatic preoccupation and loss of libido), to find out the relationship between the severity of symptoms and platelet 5-HT concentration. Male and female patients had significantly lower platelet 5-HT concentration than 62 male and 38 female healthy subjects. Gender-differences in platelet 5-HT values observed in healthy subjects were not found in patients. Platelet 5-HT concentration differed in the groups of patients with the different scores of particular somatic symptoms (loss of appetite and loss of libido), but was similar in patients with other somatic symptoms. There was no relationship between platelet 5-HT concentration and the severity of somatic symptoms, or between platelet 5-HT concentration and age of the patients. Gender-related differences in the occurrence of somatic symptoms were detected in patients with the different degrees of weight loss, somatic preoccupation and loss of libido. Our results suggest that platelet 5-HT concentration could not be used as a biological marker for the severity of somatic symptoms in chronic renal patients on HD. 相似文献