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1.
We have succeeded in recording short and middle latency vestibular evoked responses in human subjects. The head was held rigidly in a special, patented head holder, constructed individually for each subject, which gripped the teeth of the upper jaw. The stimulus consisted of 2/sec steps of angular acceleration impulses produced by a special motor with intensities of about 10,000 degrees/sec 2 and with a rise time of 1-2 msec. The electrical activity was recorded as the potential difference between special forehead and mastoid electrodes having a large, secure contact area with the skin. The activity was digitally filtered and averaged in 2 separate channels by means of a Microshev 2000 evoked response system. The short latency responses, with peaks at about 3.5 msec (forehead positive), 6.0 msec (forehead negative) and 8.4 msec (forehead positive; bandpass: 200-2000 Hz; average of 1024 trials), had amplitudes of about 0.5 microV. The middle latency responses had peaks at about 8.8 msec (forehead positive), 18.8 msec (forehead negative) and 26.8 msec (forehead positive; 30-300 Hz; N = 128 trials), with larger amplitudes (about 15 microV). These responses were consistently recorded in the same subject at different times and were similar in different normal subjects. Strenuous control experiments were conducted in order to ensure that these responses are not artefacts due to the movement of conducting media (head, electrodes and leads) in the electromagnetic field of the motor and are elicited by activation of normal labyrinths.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
2.
Scleroderma is a chronic disease that has been associated with immune dysfunction. One of the oral manifestations is microsomia, a result of collagen deposition in the perioral tissues. The complexity of treating these patients includes limited mouth opening ability, and difficulty inserting and removing dentures due to finger deformity. This article will describe an appliance specially designed especially for scleroderma patients, which facilitates treatment of the patient with removable partial dentures (RPD).  相似文献   
3.
Reconstruction of pectus excavatum with silicone implants.   总被引:1,自引:0,他引:1  
The pectus excavatum deformity is characterised by a deep depression usually involving the lower one-half to two-thirds of the sternum. The indications for surgery are often aesthetic. Extensive procedures, requiring fracturing and remodelling of the chest wall skeleton are associated with high morbidity and high rate of complications. In this article we describe our renewed experience with reconstruction of mild and moderate pectus excavatum deformities with custom made prefabricated silicone implants. The fabrication of the implant and the surgical technique are described in detail. An excellent aesthetic correction of the deformity was achieved in all of the patients in our series, with high patient satisfaction rate. We conclude that with careful patient selection, artistic implant fabrication and meticulous surgical technique, this approach achieves excellent aesthetic correction with minimal morbidity and a low complication rate and therefore should maintain its place in the armamentarium of surgical techniques for reconstruction of pectus deformities.  相似文献   
4.
We evaluated a protocol for the accelerated detection of extended-spectrum beta-lactamases (ESBLs) in gram-negative bloodstream pathogens. Two hundred eighty-three blood culture bottles were subjected to direct ESBL testing by inoculating samples directly from blood culture bottles onto agar plates containing cefotaxime and ceftazidime disks, with and without clavulanate. Standard ESBL testing in accordance with the NCCLS guidelines after subculturing on agar plates was performed in parallel. Results of the direct ESBL testing were reported 2.3 days sooner and were comparable to those of the standard NCCLS method with sensitivity, specificity, and positive and negative predictive values of 100, 98, 94, and 100%, respectively.  相似文献   
5.
Screening of the Mycobacterium leprae cosmid library with pooled sera from lepromatous leprosy (LL) patients by a colony immunoblot technique resulted in the identification of about 100 colonies that produced immunologically reactive proteins. Twenty-four of these clones were purified, analyzed, and found to comprise two groups according to the reactivity of the recombinant proteins with LL sera and to the DNA restriction patterns of the recombinant plasmids and cosmids. Proteins specified by clones from group I reacted strongly with LL patients' sera on a Western blot (immunoblot), demonstrating a 15-kDa protein band designated A15. The A15 antigen also reacted with pooled sera from patients with tuberculoid leprosy from the United States and Brazil. Clones from group II did not show any reactive protein band on a Western blot, when reacted with patients' sera. DNAs from cosmids of group II all contain a 10-kb PstI fragment that hybridized to the unique repetitive M. leprae DNA. Sequence analysis of a 1.2-kb fragment containing the entire coding sequence of A15 revealed three open reading frames (ORFs), only one of which (ORF II) contains sufficient genetic information to encode for A15. Part of the A15 gene was found to exist also in a group of lambda gt11:M. leprae clones previously isolated in our laboratory by immunological screening with LL patients' sera. One of the lambda gt11 clones (L8) expresses a beta-galactosidase fusion protein with 89 amino acids from the C terminus of A15. An important result was that the fusion protein was clearly recognized by T cells from leprosy patients. Interestingly, Mycobacterium tuberculosis-stimulated T cells from M. leprae nonresponder (LL as well as borderline tuberculoid) patients were able to respond to the isolated recombinant M. leprae antigen, indicating that nonresponsiveness to M. leprae antigens can be reversible. The sequence of the M. leprae DNA fused to the beta-galactosidase gene of lambda gt11 clone L8 was identical to that of a lambda gt11:M. leprae clone isolated recently that expresses an immunologically reactive fusion protein (S. Laal, Y. D. Sharma, H. K. Prasad, A. Murtaza, S. Singh, S. Tangri, R. Misra, and I. Nath, Proc. Natl. Acad. Sci. USA 88:1054-1058, 1991). Besides the complete sequence of the A15 gene, sequencing data of two flanking ORFs are presented. Downstream from ORF II (A15), ORF III has a high degree of similarity to the genes for tomato ATP-dependent proteases that are members of a larger class of highly conserved proteases ubiquitous among prokaryotes and eukaryotes.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
6.
Low serum vitamin B(12) concentrations in pregnancy may not indicate true megaloblastic anaemia. In the present study we compared biochemical indices of vitamin B(12) deficiency (serum homocysteine and urine methylmalonic acid) in non-anaemic pregnant women with and without low serum vitamin B(12) concentrations. The groups were matched for age, parity and gestational age. No differences were found, and all values were within normal range. These results suggest that the measurement of low serum B(12) concentrations in pregnant women should be followed by analysis at the biochemical level before vitamin B(12) injections are started.  相似文献   
7.
The purpose of this study was to examine postprogram exercise motivation and adherence in cancer survivors who participated in the Group Psychotherapy and Home-Based Physical Exercise (GROUP-HOPE; Courneya, Friedenreich, Sela, Quinney, & Rhodes, 2002) trial. At the completion of the GROUP-HOPE trial, 46 of 51 (90%) participants in the exercise group completed measures of attribution theory constructs. A5-week follow-up self-report of exercise wasthen completed by 30 (65%) participants. Correlational analyses indicated that program exercise, perceived success, expected success, and affective reactions were strong predictors of postprogram exercise. In multivariate stepwise regression analyses, program exercise and perceived successwere the strongest predictors of postprogram exercise. Additionally, perceived success was more important than objective success in understanding the attribution process, and it interacted with personal control to influence expected success and negative affect. Finally, postprogram quality of life and changes in physical fitness were correlates of perceived success. We concluded that attribution theory may have utility for understanding postprogram exercise motivation and adherence in cancer survivors.  相似文献   
8.
Deficiencies of terminal complement components, particularly the latter ones, are often detected because of increased susceptibility to Neisserial infections. Herein we document the first report of C7 deficiency among a highly inbred Arab population living in the lower Galilee region of Israel. Both biochemical and molecular analysis were performed on samples from infected survivors and parents of children who succumbed to Neisserial infections in a 4-year period. Only the index case who suffered recurrent infections and a sibling who had not suffered an infection during the outbreak were found to be C7-deficient. The mutation was found to be the one previously described to be prevalent among Israeli Jews of Moroccan ancestry (mutation G1135C). The implications of this finding are discussed in the context of family pedigree, the protective effect of complement deficiency, and the clinical outcome.  相似文献   
9.
Crude preparations of a precursor of the antiviral factor (pre-AVF) were made from noninfected Nicotiana leaves, either carrying the N-gene or from which the N-gene is absent. These pre-AVF preparations could be activated to give antiviral activity. Crude enzyme preparations, made only from N-gene-carrying plants, but regardless of TMV-infection, served as activating systems. This activation requires ATP, CAMP and cGMP and is associated with the appearance of a new phosphor ylated material seen by polyactylamide gel electrophoresis. The induced antiviral activity has been purified as AVF but was separated from the phosphorylated material. It is proposed that an activating system, determined by the N-gene, is itself being activated through phosphorylation following TMV infection and processes a “pre-AVF” to make active AVE.  相似文献   
10.
Three random basic copolymers of amino acids were tested for their effect on experimental allergic encephalomyelitis (EAE). One of these copolymers denoted as Cop 1, composed of alanine, glutamic acid, lysine and tyrosine, with a molecular weight of 23 000, showed a marked suppressive effect on the disease. The intravenous administration of Cop 1 in physiological saline, as late as 5 days following the challenge with the disease-inducing dose of the basic encephalitogenic protein, reduced the clinical incidence of EAE from 64% in the control group to 22%; the histological lesions were also decreased both in prevalence and in severity. The suppressive effect on the disease attained by the synthetic copolymer is of the same order of magnitude as that previously reported for the basic encephalitogen. The effect of the copolymers appears to be specific, since neither an acidic amino acid copolymer, nor unrelated basic proteins, had any protective action. On the other hand, a second batch of Cop 1 showed activity identical to that of the first batch. The potential applicability of this non-encephalitogenic and non-immunosuppressive material is discussed.  相似文献   
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