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DNA sequencing with chain-terminating inhibitors   总被引:9666,自引:2378,他引:9666       下载免费PDF全文
A new method for determining nucleotide sequences in DNA is described. It is similar to the "plus and minus" method [Sanger, F. & Coulson, A. R. (1975) J. Mol. Biol. 94, 441-448] but makes use of the 2',3'-dideoxy and arabinonucleoside analogues of the normal deoxynucleoside triphosphates, which act as specific chain-terminating inhibitors of DNA polymerase. The technique has been applied to the DNA of bacteriophage varphiX174 and is more rapid and more accurate than either the plus or the minus method.  相似文献   
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赵莉  宋文刚 《医学争鸣》2007,28(15):1437-1439
DC-SIGN是DC表面识别多种病原微生物的受体.一方面,DC借助DC-SIGN对固有免疫及适应性免疫发挥免疫调节作用;另一方面,DC-SIGN又成为某些病原微生物如肝炎病毒借以逃逸机体免疫防御功能的靶分子.我们就DC-SIGN的结构及功能、与病毒的相互作用等方面进行阐述.  相似文献   
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A case of chylous ascites occurring after elective abdominal aortic aneurysm repair is described. The patient was initially managed conservatively with hyperalimentation and intermittent drainage of the retroperitoneal collection, but, this proved inadequate and a peritoneo-venous shunt was inserted. Although the shunt appeared to work well the patient finally died of septicaemia.  相似文献   
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Writer's cramp is a task-specific dystonia that leads to involuntary hand postures during writing. Abnormalities of sensory processing may play a pathophysiological role in this disorder. Electrophysiology studies in a monkey model of focal dystonia have revealed de-differentiation of sensory maps and the existence of single cells in hand regions of area 3b with enlarged receptive fields that extend to the surfaces of more than one digit. These changes may lead to abnormal processing of simultaneous sensory inputs. To study abnormal processing of simultaneous sensory information in adult humans with writer's cramp, we used functional magnetic resonance imaging to compare the response in primary sensory cortex with simultaneous tactile stimulation of the index and middle finger, with the response to stimulation of each finger alone. We tested five patients with writer's cramp and seven unaffected (normal) subjects. In the normal subjects, a linear combination of the activation patterns for individual finger stimulation predicts the pattern of activity for combined stimulation with 12% error. In writer's cramp patients, the linear combination predicted the combined stimulation pattern with 30% error. Results indicate a nonlinear interaction between the sensory cortical response to individual finger stimulation in writer's cramp. This altered interaction may contribute to the motor abnormalities.  相似文献   
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INTRODUCTION: The objectives of this study were to determine the economic, clinical, and quality-of-life outcomes associated with olanzapine treatment in patients diagnosed with mania. METHODS: Patients with a diagnosis of bipolar I disorder with manic or mixed episodes were enrolled in a randomized controlled trial. The study design comprised a 3-week acute phase followed by a 49-week open label extension. In the open label extension, the use of lithium and fluoxetine was permitted for patients who experienced breakthrough symptoms. Clinical, economic, and quality-of-life outcomes of treatment were assessed. RESULTS: During the acute phase, olanzapine patients experienced a statistically significant greater mean improvement from baseline on the Y-MRS total score compared to the placebo patients. In the open label extension, patients experienced a statistically significant mean change of 11.8 units on the Y-MRS from the end of the acute phase. When compared to costs incurred in the previous 12 months of therapy, patients experienced savings of almost $900 per month during the 49 weeks of olanzapine therapy. These cost savings were largely driven by reductions in in-patient costs during the open label extension. Health-related quality of life improvements measured by the SF-36 were seen on several dimensions both in the 3-week acute phase as well as in the 49-week open label extension. CONCLUSION: From a clinical, economic, and quality-of-life outcomes standpoint, olanzapine had a significant impact in the treatment of mania, and could be considered a cost-effective treatment option for use in this population if these findings are extrapolated to non-clinical trial populations.  相似文献   
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The diagnosis of hibernoma has historically been made by histopathologic examination and finding of characteristic brown fat cells with granular multivacuolated cytoplasm. The diagnosis of hibernoma may be complicated, however, because seemingly diagnostic cells could be mistakenly identified as lipoblasts, leading to the erroneous diagnosis of well-differentiated liposarcoma. Cytogenetic alterations in lipomatous tumors are well established and could be used for diagnostic purposes. Previous cytogenetic abnormalities reported in hibernomas have included alteration of 11q13 region. Here, we present a case of a hibernoma with a novel cytogenetic alteration involving a reciprocal translocation between 9q and 11q that was useful in establishing the final diagnosis.  相似文献   
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