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1.
Phospholamban (PLN) was expressed in Escherichia coli as a protein fusion with glutathione S-transferase (GST). GST-PLN was mostly present in the insoluble protein fraction and accounted for approximately 50% of total insoluble protein. Attempts to suppress inclusion body formation or to use GST as an affinity-purification tag failed. A successful purification method is based on preparative SDS/PAGE and electrodialysis. From 1 g cells we typically purified 13.5 mg fusion protein with a PLN content of 2.8 mg. We genetically inserted an enterokinase (EK) protease site just in front of the PLN sequence and demonstrated the proteolytical liberation of PLN from the carrier protein. The approach described represents a substantial advancement in PLN expression and purification. 相似文献
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BACKGROUND: The effect of topical corticosteroids after excimer laser photorefractive keratectomy (PRK) remains a matter of some controversy. Refractive effects may be different according to the amount of myopia and timing of instillation. METHODS: Two groups of patients were studied: Study A consisted of 215 eyes (128 patients) with PRK (mean baseline myopia, -6.53 +/- 2.22 D) that received no corticosteroids (No Corticosteroid Group) unless significant regression or corneal haze appeared (Delayed Corticosteroid Group), and in Study B, we randomly assigned eyes to the Initial Corticosteroid Group (mean baseline myopia, -6.39 +/- 1.84 D) or the No/delayed Corticosteroid Group (mean baseline myopia -5.78 +/- 2.02 D). Clinical results after PRK for low-to-moderate and high myopia were compared. RESULTS: In the first group, 70.9% (73 eyes) of moderately myopic eyes (mean, -4.56 +/- 1.10 D) belonged to the No Corticosteroid Group that had a mean refraction of -5.39 +/- 1.77 D. Delayed Corticosteroid Group eyes were more myopic (mean, -7.52 +/- 2.10 D), and showed more severe haze than those in the No Corticosteroid Group. In study B, only in high myopes with more than -6.00 D (mean, -7.76 +/- 1.15 D) did refraction and corneal haze outcomes show significant difference between the Initial Corticosteroid Group and the No/delayed Corticosteroid Group. CONCLUSIONS: The effects of topical corticosteroids after PRK were less in moderate myopes compared to high myopes. Delayed instillation of corticosteroids did not reverse the regression or haze whereas initial instillation showed a beneficial effect on high myopes but not on moderate myopes. 相似文献
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Nusslock Robin; Abramson Lyn Y.; Harmon-Jones Eddie; Alloy Lauren B.; Hogan Michael E. 《Canadian Metallurgical Quarterly》2007,116(1):105
On the basis of the behavioral approach system (BAS) dysregulation theory of bipolar disorder, this study examined the relation between occurrence of a BAS activation-relevant life event--goal striving--and onset of hypomanic and depressive episodes and symptoms. In particular, the authors examined the relation between preparing for and completing final exams (a goal-striving event) and onset of bipolar spectrum episodes and symptoms in college students with bipolar II disorder or cyclothymia (i.e., "soft" bipolar spectrum conditions). One hundred fifty-nine individuals with either a bipolar spectrum disorder (n=68) or no major affective psychopathology (controls; n=91) were further classified on the basis of whether they were college students (i.e., completed final exams). Consistent with the BAS dysregulation theory, preparing for and completing final exams was associated with an increase in hypomanic but not depressive episodes and symptoms in individuals with a soft bipolar spectrum diagnosis. Furthermore, self-reported BAS sensitivity moderated the presence of certain hypomanic symptoms during final exams. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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HE Montgomery P Clarkson CM Dollery K Prasad MA Losi H Hemingway D Statters M Jubb M Girvain A Varnava M World J Deanfield P Talmud JR McEwan WJ McKenna S Humphries 《Canadian Metallurgical Quarterly》1997,96(3):741-747
PURPOSE: To determine the radiologic characteristics of cystic dystrophy of the duodenal wall. MATERIALS AND METHODS: Ten patients with cystic dystrophy of the duodenal wall and chronic pancreatitis underwent ultrasonography (US) (n = 10), computed tomography (CT) (n = 10), endoscopic US (n = 5), and endoscopic retrograde cholangiopancreatography (ERCP) (n = 9). Cystic dystrophy of the duodenal wall was classified as either cystic or solid. The imaging findings were retrospectively analyzed and compared with findings at pancreatoduodenectomy (n = 10). RESULTS: The more frequent cystic type (n = 7) of cystic dystrophy of the duodenal wall was characterized by the presence of easily recognizable cystic lesions (diameter, more than 1 cm), located within the thickened wall of the second portion of the duodenum. The solid type (n = 3) of cystic dystrophy of the duodenal wall demonstrated fibrous thickening of the duodenal wall within which small cysts (diameter, less than 1 cm) were present. The intraduodenal cysts were usually elongated or bilobate with a thick wall. The thickening of the duodenal wall appeared as a solid layer between the duodenal lumen and the pancreas, hypoechoic at US, isoattenuating at unenhanced CT, and hypoattenuating in the early phase (after initiation of infusion of contrast material) and isoattenuating in the late phase (after completion of infusion) at contrast material-enhanced CT. Findings at retrospective analysis of CT and endoscopic US images were characteristic. CONCLUSION: Imaging modalities, notably CT and endoscopic US, helped establish the diagnosis of cystic dystrophy of the duodenal wall. 相似文献
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Summary form only given. The consequences of dynamic interaction caused by physical contact with objects is discussed. Robotic experience has demonstrated that contact with objects can result in unstable behavior, yet humans contact and manipulate objects with no evidence of contact instability. It is shown that impedance control may be used in a robot or prosthesis to eliminate contact instability. Evidence that a similar approach may be the basis of human motor behavior in comparable tasks is reviewed. A model based on exploitation of apparent neuromuscular impedance is shown to be remarkably competent to reproduce fine details of multi-joint reaching behavior. The implication of this model is that some of the stability properties associated with posture are preserved during movement and may be used to simplify its execution. Experiments in which human subjects held the handle of a manipulandum and performed simple reaching motions to visually presented targets are described 相似文献
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C Sergi K Jundt S Seipp T Goeser L Theilmann G Otto HF Otto WJ Hofmann 《Canadian Metallurgical Quarterly》1998,29(6):861-871
BACKGROUND/AIMS: The aim of the study was to assess the impact factor of HCV and HGV in fulminant hepatic failure. METHODS: The 5'-untranslated regions of HCV RNA and HGV RNA and a segment of the core antigen sequence of HBV were amplified after extracting the nucleic acids from snap-frozen tissue aliquots from explanted livers of 26 consecutive patients undergoing orthotopic liver transplantation for fulminant hepatic failure preoperatively diagnosed as either autoimmune (n=2), HAV/HBV (n=8), toxic (n=4) or aetiologically unknown (n=12). RESULTS: HCV RNA was detected in five of 26 (19.2%) livers with fulminant hepatic failure. All five HCV RNA-positive livers belonged to the group of non-toxic, non-autoimmune liver failure (n=20), three of them were found in the group of liver failure with unknown aetiology (n=12) and two in the group of HBV-associated liver failure (n=7), making an HCV incidence of 25%, 25% and 28.6%, in the different groups, respectively. HGV RNA was detected in 10 of 17 (58.8%) explants and in all four groups of fulminant hepatic failure as defined preoperatively. HBV DNA was identified in six livers of 26 patients (23.1%) with fulminant hepatic failure. Neither HCV RNA nor HBV DNA was detected in the livers of patients with toxic or autoimmune fulminant hepatic failure. CONCLUSIONS: These results indicate that HBV and HCV, but not HGV, play an aetiologic role in fulminant hepatic failure. HCV-positive cases were concentrated either in the group of otherwise unexplained fulminant hepatic failure or in the group of HBV fulminant hepatic failure. HGV-positive cases, on the other hand, were found within all four preoperatively defined groups, indicating a role as cofactor rather than as single aetiologic agent. 相似文献
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