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31.
We have previously shown that the estrogen responsiveness of the human lactoferrin gene in a transient transfection system is mediated through an imperfect estrogen response element (ERE) and a steroidogenic factor 1 binding element (SFRE) 26 bp upstream from ERE. Reporter constructs containing SFRE and ERE respond to estrogen stimulation in a dose-dependent manner, whereas mutations at either one of the response elements severely impaired the estrogen responsiveness. In this study, we demonstrated that estrogen receptor (ERalpha) binds to the human lactoferrin gene ERE and forms two complexes in an electrophoresis mobility shift assay (EMSA). These complexes could be supershifted by an antibody to ERalpha. We also showed that in normal cycling women, lactoferrin gene expression in the endometrium increases during the proliferative phase and diminishes during the luteal phase. This in-vivo study thus supported the finding from transient transfection experiments that the human lactoferrin gene expression is elevated in an environment with a high level of estrogen. The estrogen effect on lactoferrin gene expression in the rhesus monkey endometrium was studied by Western blotting and immunohistochemistry. The immunohistochemistry results showed that immunoreactive lactoferrin protein was not detectable in the untreated ovariectomized monkey endometrium, was elevated by estrogen treatment, and was suppressed by sequential, combined estrogen plus progesterone treatment. In conclusion, this study has shown that lactoferrin gene expression is responsive to estrogen in primate endometrium.  相似文献   
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Immunological recovery after measles   总被引:4,自引:1,他引:4       下载免费PDF全文
Twenty-two children with measles were studied at the stage of the rash and 6 weeks later, and results compared with matched controls. The total lymphocyte count and lymphocyte subpopulations with T- and B-cell markers and those with absence of both markers (null cells) were significantly below control levels in the acute phase. At 6 weeks the B-cell and null-cell counts were still significantly diminished. The function of T cells assessed by 14C uptake of phytohaemagglutinin-stimulated lymphocytes and the delayed skin hypersensitivity reaction to dinitrochlorobenzene was impaired during the acute stage, and this persisted for 6 weeks. Over the 6 weeks of study there was a small but significant rise in serum IgG, IgM and complement factors.  相似文献   
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We have developed a chemotactic assay in which migrated cells are quantitated by measuring levels of an endogenous cellular component. The endogenous component chemotactic assay (ECCA) employs standard double-membrane, blind-well methodologies but is unique in that leukocyte migration is quantitated by measuring lactic dehydrogenase (LDH) activity endogenous to cells that have migrated. This approach avoids the tedium of microscopic counting as well as the problems associated with cell-labeling techniques. Using the ECCA technique we have shown: (1) that N-formylmethionyl-leucyl-phenylalanine (fMLP) is both chemokinetic and chemotactic for human polymorphonuclear neutrophils (PMNs); (2) that both incubation time and starting PMN density affect the proportion of cells that migrate; (3) that approximately 30% of the available PMNs eventually migrate; and (4) that PMN "fall off" from membranes, readily detectable by this assay, is affected by starting PMN density, incubation period, and nature of the attractant. The technique as presented can detect migration when a starting cell density as low as 7 x 10(4) PMNs/well is employed and can be made more sensitive by increasing the period over which LDH is allowed to act. Considerable potential exists to further apply the ECCA concept to the study of the migration of subpopulations of cells in mixtures by assaying for distinguishing endogenous cellular markers.  相似文献   
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Fifteen patients with Zollinger-Ellison syndrome followed at the National Institutes of Health with extensive metastatic disease had an actuarial 5-year survival of 20%. Therefore, in 1982 a prospective study to examine the effect and feasibility of removing all gross tumor in selected patients with extensive metastatic disease was instituted. Five patients with extensive metastatic gastrinoma confined to the abdomen in whom imaging studies suggested the possibility of complete surgical resection were entered into this study and underwent attempted complete surgical resection and chemotherapy with streptozotocin, doxorubicin, and 5-fluorouracil. Median follow-up was 24 months. Surgical resection of all gastrinoma was possible in 4/5 patients attempted. In one patient in whom all gross disease could not be resected, the residual tumor progressed and the patient died 19 months after operation. All four patients with all disease resected appeared to benefit since all of them had a significant reduction in antisecretory medications and are enjoying normal activity and work. Three patients have had no detectable tumor on follow-up, and two of these patients are clinically and biochemically "cured" with normal fasting gastrin levels and negative provocative gastrin tests at 14 and 32 months. Therefore, aggressive resection of metastatic disease in selected patients with malignant gastrinoma is recommended.  相似文献   
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The present study was undertaken to evaluate the systemic absorption and cervical tissue uptake of all-transretinoic acid (TRA), delivered via a collagen spongecervical cap delivery device in patients with intraepithelial cervical dysplasia. Ten patients with histologically proven mild or moderate cervical dysplasia were included in this pharmacologic study. The two TRA concentrations (0.05% and 0.372%) selected for study represent the starting and maximally tolerated doses used in phase I clinical trial. All-trans-retinoic-11-3H acid (3H-TRA, 500 Ci) was used to facilitate cervical tissue uptake studies. Cervical biopsies and post-treatment blood samples were obtained from each patient after TRA exposure. The uptake of TRA into cervical tissues four hours after drug administration was significantly increased at the maximally tolerated TRA dose. There was a rapid decrease in cervical tissue concentration of TRA at the 0.372% dose between 4 and 24 h after drug exposure, suggesting a relatively short elimination half-life of TRA in cervical tissues. HPLC analysis of post-treatment blood samples indicate that there was no systemic absorption of TRA after local cervical administration.  相似文献   
36.
Wesley N 《Urban health》1984,13(10):38-39
This feature of Urban Health covers a wide range of topics related to metropolitan hospitals, both public and private. This month's column discusses a hospital setting with which relatively few practicing physicians are well acquainted--the Black community hospital. More than 500 such hospitals were established in years following the Civil War, but their numbers have dwindled steadily in recent decades to the point where today only a handful survive. A recasting of missions and a thrust into the middle class population are among strategies needed to halt the demise of these institutions, says the author.  相似文献   
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Burn survivors experience myriad associated symptoms such as pain, pruritus, fatigue, impaired motor strength, post-traumatic stress, depression, anxiety, and sleep disturbance. Many of these symptoms are common and remain chronic, despite current standard of care. One potential novel intervention to target these post burn symptoms is transcranial direct current stimulation (tDCS). tDCS is a non-invasive brain stimulation (NIBS) technique that modulates neural excitability of a specific target or neural network. The aim of this work is to review the neural circuits of the aforementioned clinical sequelae associated with burn injuries and to provide a scientific rationale for specific NIBS targets that can potentially treat these conditions. We ran a systematic review, following the PRISMA statement, of tDCS effects on burn symptoms. Only three studies matched our criteria. One was a feasibility study assessing cortical plasticity in chronic neuropathic pain following burn injury, one looked at the effects of tDCS to reduce pain anxiety during burn wound care, and one assessed the effects of tDCS to manage pain and pruritus in burn survivors. Current literature on NIBS in burn remains limited, only a few trials have been conducted. Based on our review and results in other populations suffering from similar symptoms as patients with burn injuries, three main areas were selected: the prefrontal region, the parietal area and the motor cortex. Based on the importance of the prefrontal cortex in the emotional component of pain and its implication in various psychosocial symptoms, targeting this region may represent the most promising target. Our review of the neural circuitry involved in post burn symptoms and suggested targeted areas for stimulation provide a spring board for future study initiatives.  相似文献   
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