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81.
In an eosinophilic population of 47 boys of the same age, a large proportion (92%) were helminth infested or atopic, or both, compared with 36% of 36 controls. The methods used to detect these conditions were not costly or elaborate, except for the radioallergosorbent test, which was used to measure concentrations of circulating IgE antibodies to atopic allergens. It is suggested that an economical approach to detect helminthiasis and atopy in cases of eosinophilia is adopted using the methods employed here, with skin prick tests replacing the radioallergosorbent test.  相似文献   
82.
Characterization of FMR1 proteins isolated from different tissues   总被引:1,自引:5,他引:1  
FMR1 protein expression was studied in different tissues. Inhuman, monkey and murine tissues, high molecular mass FMR1 proteins(67–80 kDa) are found, as shown in lymphobiastoid celiiines. The identity of these proteins was confirmed by theirabsence in tissues from patients with the fragile X syndromeand a FMR1 knock-out mouse. An IIe367Asn substitution in theFMR1 protein did not aiter the transiation, processing and localizationof FMR1 proteins in lymphoblastoid cells from a patient carryingthis mutation. All the high molecular mass FMR1 proteins isolatedfrom normal lymphoblastoid cells and cells from the patientwith the IIe367Asn substitution were able to bind RNA. However,the FMR1 proteins of the patient had reduced affinity for RNAbinding at high salt concentrations. In some human, monkey andmurine tissues low molecular mass FMR1 proteins (39–41kDa) were found, which had the same N terminus as the 67–90kDa isoforms, but differ in their C terminus and are thereforemost likely the result of carboxy-terminal proteolytic cleavage.These low molecular mass FMR1 proteins did not bind RNA, incontrast with the high molecular mass FMR1 proteins. The significanceof these low molecular mass proteins remains to be studied.  相似文献   
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84.
Depth and field size dependence of the sensitometric curves of radiographic films have been studied by various groups. Limited information is, however, available on the magnitude of the variations in sensitometric curves applied in clinical practice in different institutions. In this study we assessed in a systematic way the effect of the various parameters influencing the shape of the sensitometric curve: batch composition, irradiation conditions, film processing, and film scanning. Two types of film, Kodak X-Omat V and CEA TVS, were irradiated, processed, and analyzed in three different institutions. The interinstitutional variation of the sensitometric curves, expressed as the OD variation at 50 cGy, can be up to 32% and is mainly caused by differences in film processing and to a lesser degree to differences in batch composition, film scanning, and irradiation conditions. For the Kodak films, the average OD difference at 50 cGy between the three institutions is 17% as a result of differences in batch composition and 25% due to differences in processing conditions. For the CEA films these data are 6% and 24%, respectively. The long-term variation of the sensitometric curves of KODAK films in one institution was smaller than the differences in batch composition between the three institutions. The sensitometric curves of CEA films showed in one institution a large variation with time; the shape gradually varied from sigmoidal to quasilinear. By using relative OD values rather than absolute OD values, variations in sensitometric curves of KODAK films can be reduced to 2%. Consequently, one sensitometric curve is sufficient to derive relative dose values. If processing conditions are well controlled, it might therefore be advantageous to determine the absolute OD only at one or two dose values, in combination with a "universal" relative sensitometric curve.  相似文献   
85.
86.
In this study, we measured direct and indirect T-cell alloresponses mediated by CD4(+) and CD8(+) T cells in three mouse transplantation models: skin, cornea, and retina. We show that the contribution of direct and indirect antigen recognition pathways to the alloresponse to fully allogeneic grafts varies depending upon the nature of the tissue/organ transplanted. The implications of this finding for understanding the cellular mechanisms by which rejection is mediated in different transplant models are discussed.  相似文献   
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88.
With the increased popularity of complementary and alternative medicine (CAM), there is a growing interest in the topic among physicians, residents, and medical students, who feel an increased need to have proper instruction about CAM therapies. Medical schools and residency programs are starting to respond to this demand, having realized that to provide better care and foster an improved patient-doctor relationship, physicians should become informed consultants, and be able to provide educated advice about CAM to their patients and help them integrate any CAM therapies shown to be safe and effective into their health care. The authors acknowledge that opinions differ about the adequacy of research findings to certify the safety and efficacy of specific therapies, and stress that physicians' decisions about CAM use should be subject to the same exacting criteria employed by researchers to evaluate any new therapies. The authors report on CAM curriculum developments in Germany, Canada, and the United States that illustrate various approaches to the question, "What should be taught in a CAM course?" In most cases, the approach is to teach about CAM therapies, although in others, therapies that the curriculum planners considered useful and safe are being integrated into the medical curriculum.  相似文献   
89.
90.
Demyelination events or multiple sclerosis following hepatitis B virus (HBV) vaccination have been reported. We therefore compared the T-cell response to HBsAg in patients with CNS demyelination following HBV vaccination and in HBV-vaccinated healthy individuals. Our data showed no differences in terms of T-cell proliferation or cytokine production between these groups and may help to allay concerns that HBV vaccination might trigger a deleterious immune response.  相似文献   
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