Superstructures of the Pb/Ge(001) system.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to K Cho.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The Mtv-6 provirus has an incomplete genome, but retains a functional superantigen gene (sag) which directs the thymic deletion of CD4+ T cells expressing T cell receptors containing the V beta 3 or V beta 5 chains. To better understand the Mtv-6 superantigen, the structure and biological activity of the Mtv-6 provirus was analyzed. First, the complete nucleotide sequence was determined, and the mutation producing the subgenomic provirus was identified. Second, the nucleotide sequence of the 5' end of the sag gene transcript (including the splice junction) was determined by sequence analysis of a cDNA clone. Third, the superantigen activity of Mtv-6 was analyzed in mice carrying the Mtv-6 provirus isolated by selective breeding on a genetic background free of endogenous and exogenous mouse mammary tumor virus (MMTV). These studies demonstrate that (i) the Mtv-6 provirus contains a 6.2-kb deletion between two 12-bp direct repeats encompassing the central portion of the provirus but not affecting sag gene splicing or translation, (ii) the sag gene transcript has the structure predicted from previous S1 nuclease mapping studies, and (iii) the Mtv-6 superantigen can direct thymic deletion of target V beta 3+ and V beta 5+ T cells in the absence of gene products from full-length MMTV proviruses.
We report on a 5 year old girl who has hereditary progressive dystonia with marked diurnal fluctuation that improved remarkably after treatment with L-dopa. A gait analysis of the patient was done and we compared her gait patterns with those of a normal child. The following results were obtained. Before L-dopa treatment: (i) knee extension time was prolonged with genu recurvatum; (ii) the flexors and the extensors were simultaneously activated in the stance phase, and reciprocity between them was impaired; and (iii) recorded sole contact was a toe-only pattern. After L-dopa treatment: (i) the step cycle was shorter mainly due to a shorter knee extension time; (ii) genu recurvatum improved; (iii) reciprocal activities of the flexors and the extensors were observed; and (iv) a normal sole contact pattern was also observed. The data from the gait analysis were useful in stabilizing the subject's clinical condition and in evaluating changes to it.
Explore the source record for details and available documents.
Glass microelectrodes were used to record electrical activity from thin rings cut from the column of the sea anemone Calliactis parasitica. This is the first time that pulses have been recorded from the nervous system in the column. Three pulse types were detected, types A, B and C. Type A pulses are probably associated with neurones of the through-conducting nerve net. Type B pulses may be from the endodermal slow conduction system (SS2). Type C pulses have not previously been recorded and are thought to represent activity in a local nerve net. At this stage we cannot positively state whether the recordings are intracellular from endodermal myoepithelial cells or are extracellular from the sub-epithelial region.
Enteral alimentation is a crucial component of care for the malnourished patient who cannot eat. Until recently, long-term alimentation was delivered through nasogastric tubes or gastrostomy tubes placed at surgery. In the past few years, percutaneous endoscopic gastrostomy (PEG) has almost completely supplanted these traditional methods. PEG is a safer and better-tolerated procedure. The advantages of PEG over nasogastric tubes include greater social acceptance and improved cosmetic appearance, increased ease of feedings, and decreased nasal alar deformities and gastroesophageal reflux. Complications are less common with PEG than with open gastrostomy but still occur in as many as 15% of cases [1-3]. Percutaneous gastrostomies performed using fluoroscopic guidance have complications in approximately 10% of cases [4]. Despite a rapid increase in the use of percutaneous gastrostomies and their placement by radiologists [4], few published reports have described imaging findings after the placement of such tubes. This pictorial essay illustrates a spectrum of normal and abnormal imaging findings observed with the use of PEG tubes, including tube migration and misplacement, infection, tumor seeding along the PEG tube track, and a variety of gastric wall defects and pseudomasses.
Explore the source record for details and available documents.
We treated one hundred and seventy-eight epileptic children with carbamazepine (CBZ) for eight years. Among them, four children with symptomatic localization-related epilepsy, aged 11 months to 12 years, developed exacerbation of seizures. Their epilepsies were associated with hypoxic ischemic encephalopathy, head injury and ectopic gray matter. Despite the serum levels of CBZ (7.0 approximately 9.5 micrograms/ml) being within the therapeutic range, all of them had more frequent and severe partial seizures than before taking CBZ and one developed new atonic seizures. Diffuse irregular spike-wave complexes appeared on EEG in two children. Following discontinuation of CBZ in addition to replacement with phenytoin, their seizures became well-controlled and EEG findings improved except for residual focal spikes. Although CBZ is a widely used and effective antiepileptic drug for partial seizures, it should be kept in mind that CBZ may exacerbate seizures in children with symptomatic localization-related epilepsy.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.