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51.
Antiserum to polyacrylamide gel-purified simian virus 40 T antigen.   总被引:12,自引:0,他引:12  
Antisera used previously to assay SV40 T antigen have been produced in tumor-bearing hamsters. This report describes the production and characterization of antiserum produced by injection of rabbits with denatured large-T antigen (Ag) purified by immunoprecipitation and electrophoresis. The resulting antiserum reacts with native large-T Ag as determined by indirect immunofluorescence, complement fixation, and indirect immunoprecipitation assays and binds to species such as “small-T Ag” and previously described proteolytic fragments of large-T Ag.  相似文献   
52.
The effect of conditioning stimuli on the F-response was investigated in normal subjects using stimulus pairs with interstimulus intervals of 1 to 400 ms. The "recovery curve" for the F-response was found to be similar to that for the H-reflex but differences were found between male and female subjects. The significance of these findings is discussed.  相似文献   
53.
54.
Quality of Life Research - The psychometric properties of the Perth A-loneness Scale (PALs) have been extensively validated using classical test theory, but to date no studies have applied a Rasch...  相似文献   
55.
Osteosarcomatosis   总被引:10,自引:0,他引:10  
A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized.  相似文献   
56.
The Vanderbilt University medical FEL (free electron laser) Compton x-ray program is close to being operational. The FEL modifications necessary for this new capability are near completion. The transport and detection systems for electron and IR beams have been designed, delivered, and tested. We initially expect to produce 108 x-ray photons per second in the 15- to 20-keV region.  相似文献   
57.
58.
A previous study by Scarrabelotti and Carroll [60] was the first to use Jacoby's process dissociation procedure [31] with an MS group to investigate memory function, and the first to obtain metamemory judgments about recall under inclusion and exclusion instructions. Twelve months later using different words, 49 MS and 39 matched controls were readministered a word stem completion task, and made metamemory judgments about their performance. The California Verbal Learning Test (CVLT) [18], Stroop [64], and Reitan's Word Finding Test (WFT) [57], tests considered to particularly rely on conscious processing, were also readministered. At year one testing no group differences were identified in word stem completion under indirect, inclusion, or exclusion instructions, nor in conscious and automatic estimates. By contrast in year two, MS subjects remembered significantly fewer words under inclusion, and employed significantly less conscious processing than the control group to achieve remembering. However, estimates of automatic memory processing were the same for both groups. MS subjects equalled controls in the prospective and retrospective monitoring of words they consciously recalled under inclusion instructions, in both years. By contrast, each group was poor at monitoring words completed automatically under exclusion instructions; and by year two, MS subjects were even less able to monitor such material than controls. Finally by the second year, reduced conscious processing was also related to reduced performance on the Stroop, WFT, and CVLT recall and use of semantic clustering. Taken together, these findings indicate that automatic memory processing is intact in MS, but impairment in memory, metamemory, and other cognitive tasks becomes evident over time when they rely on conscious processes.  相似文献   
59.
Previous data obtained with the cloned rat mu opioid receptor demonstrated that the "super-potent" opiates, ohmefentanyl (RTI-4614-4) and its four enantiomers, differ in binding affinity, potency, efficacy, and intrinsic efficacy. Molecular modeling (Tang et al., 1996) of fentanyl derivatives binding to the mu receptor suggests that Asp147, Tyr148, Trp318, and His319 are important residues for binding. According to this model, Asp147 interacts with the positively charged opiate agonist to form potent electrostatic and hydrogen-bonding interactions. In this study, the role of weak electrostatic and hydrogen-bonding "pi-pi" interactions of the O atom of the carbonyl group and the phenyl ring structures of RTI-4614-4 and its four enantiomers with residues Tyr148, Trp318, and His319 were explored via site-directed mutagenesis. Tyr148 (in transmembrane helix 3 {TMH3}), Trp318 (TMH7), and His319 (TMH7) were individually replaced with phenylalanine or alanine. Receptors transiently expressed in COS-7 cells were labeled with [125I]IOXY according to published procedures. Mutation of Tyr148 to phenylalanine reduced the binding affinities of some mu-selective agonists (2-7 fold) but did not alter the affinities of DAMGO, naloxone, and the non-selective opiates etorphine and buprenorphine. In contrast, this mutation significantly increased the binding affinities (decreased the Kd values) of [D-Ala2,D-Leu5]enkephalin, IOXY, and dermorphin. Mutation of Trp318 decreased opioid receptor binding to almost undetectable levels. Substitution of alanine for His319 significantly reduced binding affinities for the opioid ligands tested (1.3- to 48-fold), but did not alter the affinities of naloxone and bremazocine. These results indicate the importance of Tyrl48 and His319 for the binding of fentanyl derivatives to the mu receptor. Functional studies using the mutant receptors will provide additional insight into the mechanism of action of RTI-4614-4 and its four enantiomers.  相似文献   
60.
PURPOSE: We reviewed the quality and usefulness of single shot intraoperative excretory urography (IVP) for evaluating suspected upper urinary tract trauma at our trauma center. MATERIALS AND METHODS: Between 1990 and 1997 single shot intraoperative IVP for staging renal injuries was performed in 50 patients in whom clinical instability and/or major associated injuries mandated an intraoperative study. Contrast material (2 ml/kg) was injected intravenously and images were obtained after 10 minutes. The quality and usefulness of each study were scored by a single attending urologist on a scale of 1-worst to 5-best. RESULTS: Intraoperative study quality was generally good (average score 3.84). The information obtained was generally considered useful for determining urological treatment (average score 3.96). In 16 patients (32%) intraoperative IVP findings safely obviated renal exploration. No contrast medium reactions were noted and no complications developed that were attributable to intraoperative IVP. CONCLUSIONS: Intraoperative single shot, high dose IVP is safe, efficient and of high quality in the majority of cases when performed as recommended. This study often provides important information that facilitates rapid and accurate decision-making. Intraoperative IVP is a useful tool for guiding the exploration of penetrating renal injuries and confirming blunt renal injuries that may be safely observed.  相似文献   
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