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21.
RJ Wilkinson K Hasl?v R Rappuoli F Giovannoni PR Narayanan CR Desai HM Vordermeier J Paulsen G Pasvol J Ivanyi M Singh 《Canadian Metallurgical Quarterly》1997,35(3):553-557
The diagnosis of infection caused by Mycobacterium tuberculosis is of increased public health concern following increases in the number of cases in developed countries and major increases in developing countries associated with the spread of human immunodeficiency virus (HIV) infection. The specificity of purified protein derivative skin testing for the detection of infection is compromised by exposure to environmental mycobacteria. Examination of sputum detects the most infectious patients, but not those with extrapulmonary disease. The 38-kDa antigen of M. tuberculosis contains two M. tuberculosis-specific B-cell epitopes. We overexpressed the gene for this antigen in Escherichia coli and evaluated the recombinant product in in vitro assays of T-cell function and as a target for the antibody response in humans. The sensitivity and specificity of the antigen as a skin test reagent were also assessed in outbred guinea pigs. We found that 69% of healthy sensitized humans recognize the antigen in vitro, as manifested by both cell proliferation and the production of gamma interferon. Untreated patients initially have a lower frequency of response (38%); this recovers to 72% during therapy. A total of 292 patients (20 with HIV coinfection) and 58 controls were examined for production of antibody to the 38-kDa antigen by using a commercially available kit. The sensitivity of the test in comparison with that of culture was 72.6%, and the specificity was 94.9%. The antigen was also tested for its ability to induce skin reactions in outbred guinea pigs sensitized by various mycobacterial species. The antigen provoked significant skin reactions in M. tuberculosis-, M. bovis BCG-, and M. intracellulare-sensitized animals. The significance of these findings and the usefulness of this antigen in immunodiagnosis are discussed. 相似文献
22.
The effects of epithelial removal and cyclooxygenase inhibition on contractions induced by exogenous acetylcholine (ACh) and electrical field stimulation (EFS) were evaluated in horse tracheal strips and bronchial rings. Epithelial removal potentiated the response to ACh but had no influence on the response to EFS. The effect of epithelial removal was not altered by pretreating the tissues with meclofenamate, a cyclooxygenase inhibitor. In trachealis strips, meclofenamate augmented contractions induced by EFS but not by ACh. In bronchial rings, meclofenamate augmented EFS-induced contraction to a greater extent than ACh-induced contraction. These effects of meclofenamate were epithelium-independent. We conclude that horse airway epithelium produces a relaxant factor that is not a prostanoid. Endogenous prostanoids originating from non-epithelial sites inhibit only cholinergic nerves in the trachea but both parasympathetic nerves and smooth muscle in the bronchi. 相似文献
23.
Carotid-cavernous fistulas are abnormal communications between the internal carotid artery and the cavernous sinus produced by a rupture of the wall of the carotid artery or one of its branches into the sinus. Extradural branches of the internal or external carotid arteries may communicate with the cavernous sinus, producing proptosis, progressive glaucoma, and ocular vascular engorgement. Various approaches to obliterate these fistulas have evolved, many of which carry high morbidity or are precluded by anatomical considerations. Analysis of the venous anatomy of the orbit and face, including human cadaver dissections, reveals a new and safe approach to the cavernous sinus, requiring microsurgical isolation and cannulation of the superior ophthalmic vein through an anterior orbital approach. Selective embolization of a carotid-cavernous fistula can be performed successfully through this route. We present pertinent anatomy and technical considerations and the successful clinical application of these principles. Surgeons familiar with craniofacial anatomy and microvascular techniques can apply these principles and play an active role in the treatment of these complex problems. 相似文献
24.
Nonobese diabetic (NOD) mice spontaneously develop insulin dependent diabetes mellitus. The disease results from an autoimmune process which involves mononuclear cells surrounding and eventually infiltrating the pancreatic islets of Langerhans. Macrophages are thought to be the first cells to infiltrate the islets and are actively involved in the disease process because diabetes is prevented if host macrophages are depleted or inactivated. Several lines of evidence also suggest that NOD macrophages are phenotypically and functionally abnormal. In this study, allogeneic (CBA) macrophages derived from the thymus were inoculated into newborn NOD mice and these were followed for more than 250 days. Spontaneous diabetes was significantly reduced in female NOD mice (6% diabetic versus 45% of controls). Insulitis was also significantly reduced in both male and female mice compared to their control counterparts, and in most cases there were virtually no inflammatory cells in the pancreas. Allogeneic skin grafting and mixed leukocyte cultures indicated that the recipients were not tolerant of donor antigens, and donor-derived cells were not detected in the lymphoid tissues by either flow cytometry or immunohistochemistry. The results show that macrophages from diabetes-resistant donors will prevent insulitis and diabetes in most recipients, however, the mechanism for the protection is unclear, but does not appear to be due to long-term tolerance induction. 相似文献
25.
We have measured the time response of Kipp and Zonen CM-5 pyranometers to a step function of radiation and observed that the pyranometer output varied significantly from a single exponential function of time. Using a multi-exponential function to fit the experimental data, we extracted the two dominant exponential components of the signal to obtain the analytic function describing the pyranometer response. A thermal model of the pyranometer has been developed, whose response displays the observed time behaviour. The model was applied to correct the time response error of the pyranometers subject to a step function of incident radiation, and compared with a single exponential correction scheme. 相似文献
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27.
This article describes the role of certification by the American Board of Professional Psychology (ABPP) in easing the process by which psychologists move beyond their original jurisdictional boundaries to practice psychology. Meeting the requirements for licensure or certification in the various jurisdictions can be a difficult task because these requirements vary considerably from jurisdiction to jurisdiction. Other mechanisms that are available to facilitate this process include the Certificate of Professional Qualification in Psychology issued by the Association of State and Provincial Psychology Boards and certification by the National Register of Health Service Providers in Psychology. The ABPP certificate/diploma has been regarded by many state psychological associations and state boards of psychology as an appropriate way in which to recognize psychologists who are eligible for licensure/certification in a jurisdiction because of the examination requirements for board certification. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
28.
29.
Zautra Alex J.; Okun Morris A.; Robinson Sharon E.; Lee Douglas; Roth Sanford H.; Emmanual Jansen 《Canadian Metallurgical Quarterly》1989,8(1):1
Studied the relation between life stress and immune parameters for 33 30–70 yr old female rheumatoid arthritis (RA) patients interviewed during 3 routine monthly clinic checkups. Life stress from major and minor events, coping efficacy, and self-reported psychological distress were assessed, and immunofluorescence of T-cells and B-cells was performed on the blood drawn during each visit. Small stressful events were positively related to the proportion of circulating B-cells, psychological distress was inversely related to proportion of circulating T-cells, and major life events were associated with lower T-helper/T-suppressor cell ratios. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
30.