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121.
Centromeres remain the least characterized regions of human chromosomes because they have a very high content of repetitive DNA. Here, we describe a micro-dissection library from the centromeric region of human chromosome 7 and its use for generating sequence tagged sites (STSs). The library contains about 1500 clones with an average insert size of 150 bp and only about 15% of the clones harbour repetitive human DNA. Seven clones hybridizing to alphoid DNA were found to correspond to a fragment of the D7Z2 alphoid array on chromosome 7, thus confirming the origin of the library. A number of clones not containing known repetitive DNA were used to generate STSs that identified yeast artificial chromosomes (YACs) and in turn allowed the STSs to be placed on the physical map. One STS is located between the two Genethon genetic markers closest to the centromere on the q side. Another STS was located 3–4 cM away in 7q11.2, while a third identified YACs containing both low-copy and alphoid sequences that are not yet mapped but are clearly centromeric. The library therefore comprises a collection of sequences from the centromeric region of chromosome 7 that can be used to generate STSs and to map the entire centromeric region.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   
122.
The Equal Environments Assumption (EEA) in twin studies of eating pathology was investigated by examining the hypothesis that twin resemblance for eating attitudes and behaviors is affected by their degree of physical similarity. Eating attitudes and behaviors were assessed in 338 female adolescent twin pairs with a revised version of the Eating Disorder Inventory (EDI). General physical similarity as well as body size/shape similarity were assessed using ratings of color photographs, ratings of body shape, and body mass index. All physical similarity assessments were conducted blind to twin zygosity. Significant associations between physical similarity and twin similarity for eating attitudes and behaviors were not found. Mean EDI within-twin pair absolute difference scores did not differ significantly among more versus less physically-similar groups. Additionally, correlation and regression analyses failed to find a significant association between EDI absolute difference scores and physical similarity indices. The current findings provide support for the EEA in twin studies of eating attitudes and behaviors.  相似文献   
123.
Summary Background: A link between violence and depression has been shown, but not a link between violence and postpartum depression. This study sought to determine if there is an association between a history of abuse (physical, sexual, emotional as a child or adult) and postpartum depression (PPD). Method: 200 postpartum women were recruited from 6 hospitals. At 8–10 weeks postpartum, a telephone interviewer asked women about physical, emotional or sexual abuse as an adult or child and sociodemographic, obstetrical and personal medical history. PPD was assessed using the Edinburgh Postnatal Depression Scale (EPDS, score of ≥12). Abuse was determined by the Conflict Tactics Scale or the Abuse Assessment Screen. Chi-square and logistic regression were used to determine the relationship between violence and PPD. Results: 11% of women had EPDS scores of ≥12. Rates of childhood (6.5%), or adult (6.5%) physical abuse; and childhood (13%) or adult (14%) sexual abuse were reported by respondents. Emotional abuse in the current relationship (29.6%) exceeded that of childhood abuse (3.5%). Overall 43.2% of respondents had at least one form of abuse. Having a history of depression (OR = 3.3 (95% CI, 1.3–8.7)), panic attack during pregnancy (OR = 5.4 (1.6–19.0)), maternal complications (OR = 5.0 (1.7–15.1)), low social support (OR = 3.3 (1.3–8.7)) and emotional abuse (OR = 2.8 (1.1–7.4) were associated with PPD. Conclusion: Emotional abuse but not physical or sexual abuse was found to be associated with PPD. A possible explanation for this relationship may be that being in an abusive situation puts one at risk for depression and in turn, postpartum depression.  相似文献   
124.
This study attempts to point out the importance of the anatomo-clinical finding of an "hour-glass" shape to the uterus in the diagnosis and treatment of cervical pregnancy. From 1973 to 2001, four cases of cervical pregnancy were treated in the 2nd Obstetrical and Gynecological Clinic of the Aristotelion University of Salonica. The incidence was 1:13,111 pregnancies (4 cervical in 52,446 pregnancies). Three of the patients underwent bilateral ligation of the anterior trunk of the internal iliac artery using absorbable ligatures. The fourth patient (a 42-year-old), elected to have a hysterectomy. All patients were well and discharged from hospital on the seventh postoperative day. Two of the three patients treated by ligation of the anterior trunk of the internal iliac arteries subsequently had normal pregnancies and deliveries. We lost contact with the third patient. The finding of an "hour-glass" uterine shape was very helpful in the diagnosis of cervical pregnancy. The Aristotelion University of Salonica has found that treatment by ligation of the anterior trunk of the internal iliac arteries is effective, causes no complications, never ends in hysterectomy, and maintains the normal menstrual cycles and reproductive ability of the woman.  相似文献   
125.
目的:利用蒙特卡罗程序Geant4模拟13.5 MeV和6 MeV X射线照射细胞内的纳米颗粒,分析其光核反应的剂量贡献份额。方法:以纳米金颗粒(GNP)为例,分别模拟6 MeV和13.5 MeV照射细胞内的GNP,给出各自条件下由GNP造成的剂量贡献。创建水模体(0.426 mm×0.426 mm×0.426 mm),包含1 103个细胞,作为GNP的载体。在6 MeV和13.5 MeV下分别模拟细胞中包含和不包含GNP所造成的剂量沉积。结果:13.5 MeV X射线照射,其由GNP造成的剂量贡献为5.12 cGy,细胞总能量沉积为25.37 cGy,由GNP引起的剂量贡献占20.19%;6 MeV X射线照射,其由GNP造成的剂量贡献为2.87 cGy,细胞总能量沉积为23.05 cGy,由GNP造成剂量贡献约为12.46%。与6 MeV相比,13.5 MeV下由GNP光核反应造成的剂量贡献占7.7%。结论:对于细胞模型内纳米金的研究表明,GNP确实能引起额外的剂量贡献。由于GNP光核反应引起的剂量贡献很低,难以作为能够被原位激活的放射源使用。  相似文献   
126.
1049例育龄妇女下生殖道感染情况调查   总被引:2,自引:0,他引:2  
目的了解育龄妇女下生殖道感染情况,为育龄女性生殖健康提供进一步的数据资料。方法对1049例来自健康体检中心的21~40岁育龄妇女的阴道后穹窿及宫颈分泌物标本进行检测,阴道清洁度、滴虫采用显微镜镜检法,淋球菌、解脲支原体、人型支原体、真菌采用培养法,沙眼衣原体则采用免疫层析法。检测结果进行统计学分析。结果女性生殖道感染的感染率为53.3%,其中混合感染率为9.8%,而清洁度异常率仅为28.4%;前三位病原体感染依次为解脲支原体(35.9%)、衣原体(18.1%)、真菌(6.7%)。结论女性生殖道感染情况严重,具有隐匿性,应加强对无症状感染的育龄妇女的监测。  相似文献   
127.
The Oka vaccine strains of varicella-zoster virus (VZV) have a significantly different BgII DNA restriction pattern from that of American wild-type isolates of VZV. This difference consists primarily of an additional BgII site, which lies within the BamHI "D" fragment. In conjunction with a study of the efficacy of an experimental Merck/Oka VZV vaccine, the area of the genome from which the most marked restriction pattern alteration arises was studied more closely to determine if there are other significant differences between the Oka strains and American wild-type strains. BamHI "D" fragments from the DNA of the Oka parent strain (the progenitor of the vaccine strain), the RIT/Oka vaccine strain (a derivative of the Oka parent strain), the Merck/Oka vaccine strain, and the EF strain (an American wild type), were submitted to extensive endonuclease digestion studies to ascertain if additional unique restriction sites are present in the Oka parent or vaccine strains. The extra BgII restriction site characteristic of the Merck/Oka vaccine strain is also present in the DNA of the parent virus as well as its derivatives and was therefore not produced by the "attenuation" process. No other novel sites were found in the Oka parent or Oka-derived strains in this section of the genome. The Merck/Oka vaccine strain of VZV, despite its Japanese origin, is therefore quite similar to circulating American varicella-zoster virus strains. Varicella-zoster virus DNA, at least in the area of the BamHI D fragment, also appears to be remarkably stable from strain to strain.  相似文献   
128.
The genome of the gray, short-tailed opossum, Monodelphis domestica, will be the first of any marsupial to be fully sequenced. The utility of this sequence will be greatly enhanced by construction and integration of detailed genetic and physical maps. Therefore, it is important to verify the unusual recombinational characteristics that were suggested by the ‘first-generation’ M. domestica linkage map; specifically, very low levels of recombination and severely reduced female recombination, both of which are contrary to patterns in other vertebrates. We constructed a new linkage map based on a different genetic cross, using a new and much larger set of map markers, and physically anchored and oriented the linkage groups onto chromosomes via fluorescence in-situ hybridization mapping. This map includes 150 loci in eight autosomal linkage groups corresponding to the eight autosome pairs, and spans 86–89% of the autosomal genome. The sex-averaged autosomal map covers 715 cM, with a full-length estimate of 866 cM; the shortest full-length linkage map reported for any vertebrate. The sex-specific maps confirmed severely reduced female recombination in all linkage groups, and an overall F/M map ratio =  0.54. These results greatly extend earlier findings, and provide an improved microsatellite-based linkage map for this species. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
129.
Urticaria in response to various physical stimuli has been reported in sporadic and familial patterns. The most common of these physical urticarias, dermographism, is a localized urticarial response to stroking or scratching of the skin and has not been reported previously to be familial. A four-generation family with dermographism, probably inherited as an autosomal dominant trait, is presented along with a discussion of sporadic dermographism and other types of familial physical urticarias.  相似文献   
130.
A unique case of duodenal stromal tumor In a 51-year-old man is reported. The tumor histologically showed spindle cell proliferation and numerous eosinophilic globules. Most globules were composed of tangled 45 nm thick fibrils, which were ultrastructurally Identical to 'skelnoid fibers'. The presence of glycogen granules in the tumor cells and the Immunoreactivity for α-smooth muscle actin suggested smooth muscle differentiation. Focal ultrastructural findings also supported the smooth muscle nature of this tumor. There were no immunohistochemical and ultra-structural features indicating neural differentiation. In previous studies, the presence of such 'skeinoid fibers' was suggested to be a histological marker for neural differentiation in gastrointestinal stromal tumor. However, the findings In the present case suggest that numerous 'skeinoid fibers' can be Identified in duodenal stromal tumor with smooth muscle differentiation, although this condition may be rare.  相似文献   
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