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981.
Molecular Imaging and Biology - Cancer immunotherapy has shown huge potential in the fight against cancer, but only a small proportion of patients respond successfully to treatment. Non-invasive...  相似文献   
982.
Repeated red blood cell (RBC) transfusions in preterm neonates are associated with poor outcome and increased risk for prematurity-associated diseases. RBC transfusions cause the progressive replacement of fetal haemoglobin (HbF) by adult haemoglobin (HbA). We monitored HbF levels in 25 preterm neonates until 36 weeks of post-menstrual age (PMA); patients received RBC units from allogeneic cord blood (cord-RBCs) or from adult donors (adult-RBCs), depending on whether cord-RBCs were available. Primary outcome was HbF level at PMA of 32 weeks. Twenty-three neonates survived until this age: 14 received no transfusions, two only cord-RBCs, three only adult-RBCs and four both RBC types. HbF levels in neonates transfused with cord-RBCs were significantly higher than in neonates receiving adult-RBCs (P < 0·0001) or both RBC types (P < 0·0001). Superimposable results were obtained at PMA of 36 weeks. Every adult-RBCs transfusion increased the risk for an HbF in the lowest quartile by about 10-fold, whereas this effect was not evident if combined adult- and cord-RBCs were evaluated. Overall, these data show that transfusing cord-RBCs can limit the HbF depletion caused by conventional RBC transfusions. Transfusing cord blood warrants investigation in randomised trials as a strategy to mitigate the severity of retinopathy of prematurity (NCT03764813).  相似文献   
983.

Aim

The aim of this paper is to compare the prevalence of voice disorders and the risk factors for them in different occupations with a vocal load in Slovenia.

Methods

A meta-analysis of six different Slovenian studies involving teachers, physicians, salespeople, catholic priests, nurses and speech-and-language therapists (SLTs) was performed. In all six studies, similar questions about the prevalence of voice disorders and the causes for them were included.

Results

The comparison of the six studies showed that more than 82% of the 2347 included subjects had voice problems at some time during their career. The teachers were the most affected by voice problems. The prevalent cause of voice problems was the vocal load in teachers and salespeople and respiratory-tract infections in all the other occupational groups. When the occupational groups were compared, it was stated that the teachers had more voice problems and showed less care for their voices than the priests. The physicians had more voice problems and showed better consideration of vocal hygiene rules than the SLTs. The majority of all the included subjects did not receive instructions about voice care during education.

Conclusions

In order to decrease the prevalence of voice disorders in vocal professionals, a screening program is recommended before the beginning of their studies. Regular courses on voice care and proper vocal technique should be obligatory for all professional voice users during their career. The inclusion of dysphonia in the list of occupational diseases should be considered in Slovenia as it is in some European countries.  相似文献   
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987.
The effects of peripheral blood adherent cells from normal donors on human myeloid leukemic cluster growth in agar were studied. A prior co- incubation of nonadherent leukemic cells with adherent cell monolayers from 9 out of 10 donors in liquid cultures over a 4-hr period was sufficient to reduce subsequent leukemic growth in semisolid agar cultures. Inhibition was seen with adherent to leukemic cell ratios of as low as 0.5:1. Conversely, identical numbers of adherent cells in agar cultures but separated from the leukemic cells enhanced growth more than the cultures containing human placental conditioned media alone. Because leukemic cell exposure to adherent cells was brief, a cytotoxic mechanism appeared likely; however, this could not be detected by 51Cr release. Human peripheral blood adherent cells not activated by any in vitro mechanism suppress clonal growth of human myeloid leukemic cells by a mechanism requiring cell to cell contact. Examination of the inhibition of clonal growth appears to be more sensitive than 51Cr release as an indicator of adherent cell effects on myeloid leukemia.  相似文献   
988.
Production of interleukin-1 by bone marrow myeloma cells   总被引:4,自引:3,他引:4  
Plasma cells isolated from bone marrow (BM) aspirates of 12 patients with multiple myeloma (MM) and nine patients with monoclonal gammopathy of undetermined significance (MGUS) were analyzed for production of cytokines with bone-resorbing activity, such as interleukin-1 (IL-1), tumor necrosis factor (TNF), and lymphotoxin (LT). Culture supernatants of plasma cells from MM, but not from MGUS or normal donor, invariably contained high amounts of IL-1-beta and lower amounts of IL-1-alpha. With a single exception, TNF/LT biologic activity was not detected in the same supernatants. IL-6 was present in two of five supernatants tested. Normal B lymphocytes released both IL-1 and TNF/LT activities for four days after activation in vitro; however, production of these cytokines ceased at the final stage of plasma cell. Unexpectedly, the mRNA extracted from MM plasma cell hybridized with TNF- and LT- specific, as well as IL-1-specific probes, although the culture supernatants did not contain detectable TNF/LT biologic activity. When tested in the fetal rat long bone assay, MM plasma cell supernatants displayed a strong osteoclast-activating factor (OAF) activity, which was greatly reduced but not completely abolished by neutralizing anti- IL-1 antibodies. Anti-TNF or anti-LT antibodies were ineffective in the same test. We conclude that the IL-1 released in vivo by malignant plasma cells has a major role in pathogenesis of lytic bone lesions of human MM.  相似文献   
989.
990.
Cultured with a liver-derived lipoprotein complex, T lymphocytes from 42 of 45 patients with autoimmune chronic active hepatitis generated migration inhibitory factor compared with 16 of 33 patients with primary biliary cirrhosis. Unlike T lymphocytes from patients with primary biliary cirrhosis, the T-cell reactivity of patients with chronic active hepatitis was always suppressed by T cells from normal subjects and, with two exceptions, by T cells from patients with primary biliary cirrhosis, even when these latter cells exhibited sensitization to this same antigen complex. Using a component of the whole complex, the asialoglycoprotein receptor as antigen, migration inhibitory factor was invariably released by T cells from patients with autoimmune chronic active hepatitis, but from only 2 of 8 patients with primary biliary cirrhosis sensitized to the whole complex. Thus, in autoimmune chronic active hepatitis, but not in primary biliary cirrhosis, the asialoglycoprotein receptor is invariably a target for cellular immune reactions and is associated with a suppressor T-cell defect for hepatocyte antigens.  相似文献   
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