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1.
Goldenhar and cri-du-chat syndromes: a contiguous gene deletion syndrome?   总被引:2,自引:0,他引:2  
We report a full-term male infant born to nonconsanguinous parents who had clinical features of Goldenhar syndrome and cri du chat syndrome. At birth, the infant was noted to have dysmorphic features with bilateral preauricular tags, rotated ears, bilateral epicanthic folds, a left epibulbar lipodermoid, and an accessory left nipple. After he was assessed for feeding difficulty and tachypnea, he was found to have esophageal atresia with tracheoesophageal fistula. In addition, he had a high-pitched, cat-like cry, characteristic of cri-du-chat syndrome. He also failed a hearing test. Chromosomal analysis and fluorescence in situ hybridisation studies showed an unbalanced karyotype with a terminal deletion of the segment p14 on the short arm of chromosome 5, which is consistent with the cri-du-chat locus. The association of Goldenhar syndrome and cri-du-chat syndrome in this patient suggests that the chromosome 5p14 locus may harbor a gene implicated with Goldenhar syndrome.  相似文献   
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Seven cases of complex open humeral fractures treated by external fixation are reported. The external fixation allowed the associated injuries to nerves, arteries and soft tissues to be adequately treated. Four cases developed non-union and of these, three cases treated by bone-grafting and plating united, but the one case treated by intramedullary nail without bone-graft did not unite. Frame construction and pin placement are discussed. The recommended plan for treatment of these fractures is initial external fixation until adequate soft tissue healing is achieved and sepsis controlled. Then early bone-grafting and plating is advocated if there is no progressive fracture healing. The problems and advantages encountered in the use of external fixation are also described.  相似文献   
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In the last years, granulocyte and granulocyte-macrophage colony-stimulating factors (G-CSF and GM-CSF) are being increasingly used and several cutaneous eruptions have been reported in relation to these treatments. In 1991 Horn et al. described three patients with maculopapular eruption that paralleled the time of infusion of GM-CSF. Two of the cases showed an increase in the number and size of macrophages in the biopsy specimen. Since then, several cases have been reported showing this histopathological alteration that has been considered characteristic of reaction to G-CSF or GM-CSF. Although maculopapular eruption with enlarged macrophages can appear after chemotherapy treatment, we have found that the presentation of this eruption after the beginning of cytokine treatment is suggestive of the involvement of G-CSF and GM-CSF in the eruption. We described eight cases of patients treated with G-CSF or GM-CSF that developed maculopapular eruptions with enlarged macrophages.  相似文献   
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MA6, an O157:H7-like strain, did not react with most anti-O157 kits examined; however, it had the rfbE gene that is essential for O157 expression and carried O157:H7 virulence factors. Lipopolysaccharide analysis showed that MA6 is a rough strain that does not produce the O157 antigen, but genetically, it belongs in the O157:H7 clonal group.  相似文献   
8.
Oocyte morphology predicts outcome of intracytoplasmic sperm injection   总被引:10,自引:14,他引:10  
To examine the influence of cytoplasmic morphology on the success rate of intracytoplasmic sperm injection (ICSI), the morphology of 837 metaphase II oocytes was assessed after cumulus stripping. The main abnormalities detected were excessive granularity, cytoplasmic inclusions such as vacuoles, smooth endoplasmic reticulum clustering and refractile bodies. Microinjection was performed in 538 oocytes with normal cytoplasm, 142 out of 161 with excessive granularity and 112 out of 138 with cytoplasmic inclusions. Very poor oocytes were not injected. No difference was found in fertilization rate. The embryos achieved cleaved normally and a similar number of good quality embryos among the three groups was noted. The outcome of transfer of embryos derived solely from normal oocytes (group A: 72 patients, 183 embryos) was compared with those from oocytes with cytoplasmic abnormalities (group B: 34 patients, 85 embryos). In group A, 17 clinical pregnancies (24% per patient, implantation rate 10%) were established. In group B, only one clinical pregnancy (3% per patient, implantation rate 1%) was established, from the transfer of embryos derived from oocytes with homogeneous granularity of the cytoplasm. No pregnancy resulted following the transfer of embryos from eggs with cytoplasmic inclusions. The difference was statistically significant. The outcome of ICSI is dependent on the quality of the oocytes retrieved. Normal fertilization and early embryo development were achieved in oocytes with abnormal cytoplasm morphology, but the resulting embryos failed to demonstrate the same implantation potential as those derived from oocytes with normal cytoplasm.   相似文献   
9.
DNA错配修复基因甲基化在肝细胞癌发生发展中的作用   总被引:5,自引:1,他引:5  
目的探讨DNA错配修复基因(MMR)hMLH1,hMSH2和hMSH3甲基化在肝细胞癌(HCC)发生发展中的作用。方法采用甲基化特异性聚合酶链反应(MSP)法对38例新鲜HCC组织,相应非肿瘤肝组织,2例正常的捐肝组织及6种肝癌细胞系的hMLH1,hMSH2和hMSH3基因启动子CpG岛甲基化进行检测;培养6种肝癌细胞系,MSP法检测加入5-aza-2‘-deoxycytidine前后hMSH2基因在HCC中的甲基化状态改变;逆转录.聚合酶链反应(RT-PCR)方法检测加入5-aza-2’-deoxycytidine前后hMSH2在肝癌细胞株中的mRNA表达改变。结果HCC标本中13.2%(5/38)发生了hMLH1启动子甲基化,68.4%(26/38)发生了hMSH2启动子甲基化;相应的非肿瘤肝组织中hMLH1,hMSH2启动子甲基化阳性率分别为2.6%(1/38),55.3%(21/38);2例正常肝组织中未发现甲基化;6株肝癌细胞系中有5株发生了hMSH2启动子甲基化,而未发现有MLH1启动子甲基化。所有标本中均未发现有hMSH3启动子甲基化。5-aza-2‘-deoxycytidine处理细胞株后,可部分或完全逆转hMSH2启动子甲基化,各细胞株的mRNA均有不同程度的表达增加。结论hMSH3基因启动子CpG岛甲基化与HCC的发生发展关系不大。hMSH2基因甲基化与mRNA表达密切相关,是基因表达调节的一种重要方式。hMLH1和hMSH2基因启动子CpG岛的高甲基化在HCC中是一个常见的基因改变,DNA错配修复基因尤其是hMSH2基因启动子甲基化在HCC的发生中起了重要作用,是早期事件,其可能为临床诊断HCC提供新的检测指标。  相似文献   
10.
Posterior and anterior heights, cross-sectional area and shape were measured for all the intervertebral discs in four spines from elderly human cadavers. Disc height was a minimum at the T4-5 level; thoracic discs were less wedge-shaped than those in the cervical and lumbar regions. Cross-sectional area increased from the cranial to caudal extremity; at the L5-S1 level the nucleus pulposus occupied a high proportion of this area. Cervical discs tended to have an elliptical cross-sectional shape, thoracic discs were more circular and lumbar discs tended to have an elliptical cross-section which was flattened or re-entrant posteriorly. This shape distribution was quantified by defining a shape index which had a maximum value of 1 for a circular cross-section. Orientations of the reinforcing fibres in the outer lamellae of the anterior annulus fibrosus were measured from 27 discs by X-ray diffraction. For these measurements, C3-4, T7-8 and L2-3 were chosen as representative of cervical, thoracic and lumbar discs. The fibre tilt, with respect to the axis of the spine, was significantly less in the cervical discs (at 65 degrees) than in the thoracic and lumbar discs (about 70 degrees). These findings are interpreted in relation to differing functional requirements and possible mechanisms of failure in the cervical, thoracic and lumbar regions of the spine in the light of current knowledge on the biomechanics of the intervertebral disc.  相似文献   
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