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61.
To determine the content of thyroglobulin in oxyphilic cells of the thyroid, which have been considered as non-thyroglobulin producing cells, the degree of stainability of the various oxyphilic cells for thyroglobulin was compared with that of non-oxyphilic follicular cells in either same or different lesion. A total of 13 oxyphilic lesions, including three follicular adenomas containing oxyphilic cell nodules, four pure oxyphilic cell adenomas, and six Hashimoto's thyroiditis were compared with 16 of non-oxyphilic lesions such as, seven follicular adenomas, four chronic lymphocytic thyroiditis, and five Graves' disease. Many oxyphilic cells stained positively for thyroglobulin regardless of their morphologic variation, but less intensely than the usual follicular cells in follicular adenomas, chronic lymphocytic thyroiditis, and Graves' disease. The stainability of oxyphilic cells for thyroglogulin did not show any significant correlation with morphologic features, whereas in follicular adenomas, the non-oxyphilic follicular cells forming microfollicles stained less strongly for thyroglobulin than the same cells lining large mature follicles in a reproducible way. With above findings, we concluded that oxyphilic cells maintain the functional activity in terms of thyroglobulin synthesis, although the content of the thyroglobulin is less than that of non-oxyphilic colloid forming follicular cells.  相似文献   
62.
The effect of food deprivation for 72 h or a high fat diet on [3H]naloxone binding in the discrete brain regions of male lean Zucker rats was studied. In the midbrain, both treatments increased Bmax for the high-affinity site with no change in Kd. In the cortex, the high fat diet increased Bmax for the high-affinity site. These results suggest that dietary manipulations could produce significant changes in the endogenous opioid system.  相似文献   
63.
The localization and functional characteristics of tumor necrosis factor(TNF) beta gene raise the possibility that it may be involved in the susceptibility to autoimmune thyroid diseases. To investigate whether a TNF beta gene polymorphism is associated with autoimmune thyroiditis, we analyzed the TNF beta gene polymorphism with the restriction enzyme NcoI in 48 Korean patients with atrophic autoimmune thyroiditis [23 were found to be thyrotropin binding inhibitor immunoglobulin(TBII) positive, 25 TBII negative], 52 goitrous autoimmune thyroiditis, and 129 healthy controls. Two TNF beta alleles were identified from the restriction fragment length polymorphism studies of amplified genomic DNA. In atrophic autoimmune thyroiditis patients positive for TBII, 7 of 23 patients were homozygous for the TNF beta * 1 allele, 3 were homozygous for the TNF beta * 2 allele, and 13 were TNF beta * 1/2 heterozygous compared to controls(P = 0.20). Also, there were no associations between the TNF beta gene polymorphism and either TBII-negative atrophic autoimmune thyroiditis or goitrous autoimmune thyroiditis. Of the HLA-class II antigens, the frequency of HLA-DR8 was significantly greater among the 23 Korean patients with TBII-positive atrophic autoimmune thyroiditis compared to control subjects (Pc = 0.003). When the HLA-DR8 positive patients with TBII-positive atrophic autoimmune thyroiditis and controls were analyzed separately, the DR8 positive patients with TBII-positive atrophic autoimmune thyroiditis had more homozygotes for the TNF beta * 1 allele(6/12, 50.0%) and no homozygotes for the TNF beta * 2 allele, as compared to the DR8 negative patients with TBII-positive atrophic autoimmune thyroiditis and DR8 positive controls(P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
64.
65.
Competitive-inhibition enzyme immunoassays for the measurement of human IgG, IgA and IgM are described. These assays can be readily performed with commercial antisera and a recently developed method for purifying human IgA and IgM with high yield. The assays described are specific, with undetectable (<0.5%) cross-reactivity between the immunoglobulin classes in all systems, except with purified IgM, which cross-reacted to 1.9% with the IgG enzyme immunoassay.Minimal detectable concentrations of 2.5±0.8 ng/ml for IgG 4.2±0.9 ng/ml for IgA and 7.2±1.4 ng/ml for IgM were recorded, indicating that these assays are particularly sensitive. There is little within-assay variation (mean coefficient of variation = 3.9%), although the between-assay variation was substantially greater (mean coefficient of variation = 23.5%). These assay systems appear to be particularly suited to the measurement of immunoglobulin production by lymphocytes in culture. In such studies the assay must be specific, sensitive and be capable of discriminating between levels of immunoglobulin produced in response to various experimental treatments.  相似文献   
66.
67.
To investigate whether the phosphorylation of extracellular signal-regulated kinase (ERK) is involved in autoimmune injury of the peripheral nervous system (PNS), the expression of phosphorylated ERK (p-ERK) was analyzed in experimental autoimmune neuritis (EAN) in rats. Western blot analysis showed that the level of p-ERK was increased significantly in the sciatic nerves of rats on days 14 (p<0.05) and 24 (p<0.01) post-immunization, compared with controls, and its reaction declined at day 30 post-immunization. Immunohistochemistry showed that p-ERK protein was weakly expressed in Schwann cells and vascular endothelial cells in the sciatic nerves of CFA-immunized control rats. In EAN-affected sciatic nerves, p-ERK immunoreactivity was found mainly in ED1-positive macrophages on days 14 and 24 post-immunization. Moreover, on days 24 and 30 post-immunization, p-ERK immunoreactivity increased gradually in the Schwann cells of rat sciatic nerves with EAN. Based on these results, we postulated that the phosphorylation of ERK has an important role in the differentiation and survival of cells, including inflammatory cells and Schwann cells, in the rat sciatic nerve in EAN. Specifically, the activation of ERK in the recovery phase of EAN paralysis seems to be related in the survival of Schwann cells.  相似文献   
68.
The effects of two kinds of induction speed of sevoflurane anesthesia on the EEG pattern were compared in the same individual using medical student volunteers: a first exposure of 4% was given, followed after full recovery, by incremental doses of 1, 2 and 4% successively, each being administered for 10min. The arterial blood level of the anesthetic was measured using gaschromatograph. The changes of EEG pattern during fast induction with 4% were not represented by the abbreviation of those observed during the slow induction with the incremental doses. The administration of 4% induced a sudden appearance of high voltage, rhythmic slow waves of 2–3Hz at 1–3min when the arterial blood anesthetic level increased maximally, which was then followed by a pattern of faster activities of 10–14Hz mixed with 5–8Hz slow waves. In contrast, the administration of incremental doses induced an increase in frequency and amplitude of EEG activities in the light plane, followed by their decreases in deeper planes. The final EEG patterns were identical for both these methods of induction. These findings confirmed our previous hypothesis that not only the arterial blood level of anesthetics but the rate of its increase are important factors determining the EEG pattern of anesthesia.(Avramov MN et al.: Effects of different speeds of induction with sevoflurane on the EEG in man. J Anesth 1: 1–7, 1987)  相似文献   
69.
Dengue virus (DENV) and Zika virus (ZIKV) belong to the Flaviviridae family of viruses spread by Aedes aegypti mosquitoes in tropical and subtropical areas. Accurate diagnostic tests to differentiate the 2 infections are necessary for patient management and disease control. Using characterized ZIKV and DENV patient plasma in a blind manner, we validated an ELISA and a rapid immunochromatographic test for ZIKV detection. We engineered the ZIKV nonstructural protein 1 (NS1) for sensitive serologic detection with low cross reactivity against dengue and developed monoclonal antibodies specific for the ZIKV NS1 antigen. As expected, the serologic assays performed better with convalescent than acute plasma samples; the sensitivity ranged from 71% to 88%, depending on the performance of individual tests (IgM/IgG/NS1). Although serologic tests were generally less sensitive with acute samples, our ZIKV NS1 antibodies were able to complement the serologic tests to achieve greater sensitivity for detecting early infections.  相似文献   
70.
Parathyroid hormone (PTH) is produced by the parathyroid glands in response to low serum calcium concentrations where it targets bones, kidneys, and indirectly, intestines. The N-terminus of PTH has been investigated for decades for its ability to stimulate bone formation when administered intermittently (iPTH) and is used clinically as an effective anabolic agent for the treatment of osteoporosis. Despite great interest in iPTH and its clinical use, the mechanisms of PTH action remain complicated and not fully defined. More than 70 gene targets in more than 90 murine models have been utilized to better understand PTH anabolic actions. Because murine studies utilized wild-type mice as positive controls, a variety of variables were analyzed to better understand the optimal conditions under which iPTH functions. The greatest responses to iPTH were in male mice, with treatment starting later than 12 weeks of age, a treatment duration lasting 5–6 weeks, and a PTH dose of 30–60 μg/kg/day. This comprehensive study also evaluated these genetic models relative to the bone formative actions with a primary focus on the trabecular compartment revealing trends in critical genes and gene families relevant for PTH anabolic actions. The summation of these data revealed the gene deletions with the greatest increase in trabecular bone volume in response to iPTH. These included PTH and 1-α-hydroxylase (Pth;1α(OH)ase, 62-fold), amphiregulin (Areg, 15.8-fold), and PTH related protein (Pthrp, 10.2-fold). The deletions with the greatest inhibition of the anabolic response include deletions of: proteoglycan 4 (Prg4, −9.7-fold), low-density lipoprotein receptor-related protein 6 (Lrp6, 1.3-fold), and low-density lipoprotein receptor-related protein 5 (Lrp5, −1.0-fold). Anabolic actions of iPTH were broadly affected via multiple and diverse genes. This data provides critical insight for future research and development, as well as application to human therapeutics. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).  相似文献   
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