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61.
Probability of cure in elderly Hodgkin's disease patients   总被引:2,自引:0,他引:2  
BACKGROUND: Elderly Hodgkin's disease patients have a poor prognosis. The question arises whether these patients need aggressive treatment or a palliative strategy. So far, as a consequence of the scarcity of trials designed for them, useful information can be obtained only by retrospective analyses. METHODS: We retrospectively studied clinical data from 567 patients recorded from 1982 to 1989 in the Piemonte Hodgkin's Disease Register (PHDR). The 65 patients over 65 years of age were compared to younger ones. We analyzed the role of disease independently of confounding variables, mainly inadequacy of staging and/or treatment, comorbidity and toxicity. RESULTS: In the elderly comorbidity was as high as 35%. Forty elderly patients (60%) entered a suboptimal plan with a low degree of aggressivity, which was different from the usual PHDR protocol. Elderly patients also had a high proportion of subsequent protocol interruptions (25%). Chemotherapy dose intensity was negatively affected by advanced age (p < 0.01 after both 3 and 6 courses of chemotherapy). Toxic deaths were significantly higher in elderly patients than in younger ones (14% vs 1%; p < 0.05). CR rates, overall survival (OS), disease-specific survival (DSS) and event free survival (EFS) were all significantly influenced by age (p < 0.01). Relapse-free survival (RFS) in patients achieving CR did not differ according to age class (77% vs 60%; p = ns). RFS was better in elderly patients entering the PHDR protocols than in those following an alternative plan (75% vs 54%; p = 0.04); however, elderly patients treated according to PHDR guidelines showed a higher incidence of toxic deaths than those treated less aggressively (23% vs 8%). The two groups had similar EFS (36% vs 24%; p = ns). CONCLUSIONS: Elderly patients who achieve CR can have good RFS and cure is possible, but the toxic cost of conventional strategies is unacceptable and selected strategies still must be found.  相似文献   
62.
Limbal epithelial stem cells are responsible for the maintenance of the human corneal epithelium and these cells reside in a specialised stem cell niche. They are located at the base of limbal crypts, in a physically protected microenvironment in close proximity to a variety of neighbouring niche cells. Design and recreation of elements of various stem cell niches have allowed researchers to simplify aspects of these complex microenvironments for further study in vitro. We have developed a method to rapidly and reproducibly create bioengineered limbal crypts (BLCs) in a collagen construct using a simple one-step method. Liquid is removed from collagen hydrogels using hydrophilic porous absorbers (HPAs) that have custom moulded micro-ridges on the base. The resulting topography on the surface of the thin collagen constructs resembles the dimensions of the stromal crypts of the human limbus. Human limbal epithelial cells seeded onto the surface of the constructs populate these BLCs and form numerous layers with a high proportion of the cells lining the crypts expressing putative stem cell marker, p63α. The HPAs are produced using a moulding process that is flexible and can be adapted depending on the requirements of the end user. Creation of defined topographical features using this process could be applicable to numerous tissue-engineering applications where varied 3-dimensional niche architectures are required.  相似文献   
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ObjectiveThis meta-evaluation aimed to summarize all available evidence regarding different fissure sealants on occlusal caries prevention, arrest, retention rate, adverse effect, and cost-effectiveness; when compared with no intervention, other preventive or minimally-invasive procedures.Materials and MethodsThe systematic reviews and meta-analyses were identified via four electronic databases and manual searching. Two independent reviewers performed study selection, data extraction, quality assessment with AMSTAR-2.ResultsAmong the 366 records yielded, 38 systematic reviews were identified as eligible 24 of them included meta-analyses. Moderate evidence has supported the efficacies of resin-based sealants (RBS) in occlusal caries prevention, arrest and cost-effectiveness compared to no interventions. Low to very low certainty of evidence suggested similar effectiveness of glass-ionomer cements in caries prevention with RBS and more superior performance of resin infiltration in arresting non-cavitated occlusal lesions.ConclusionThis meta-evaluation supports the use of RBS on permanent molars to reduce occlusal caries occurrence, arrest lesion progression and alleviate oral health inequalities between individuals of different socioeconomic status. This meta-evaluation also advocates further research on glass-ionomer cements and resin infiltration with respect to their efficacies in caries prevention and arrest.  相似文献   
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Seventeen AIDS patients were enrolled in a prospective open-label dose-finding study of octreotide (Sandostatin) therapy for refractory diarrhea. Five were nonevaluable due to progression of AIDS symptomatology, and one was excluded because of lack of confirmation of HIV infection. Five of 11 evaluable patients responded to therapy (45%); two each at 50 g and 100 g, and one at 250 g thrice daily doses. A sixth patient demonstrated a moderate reduction in stool volume at 250 g thrice daily, which, although deemed clinically relevant, did not meet the criteria for response. On discontinuation of therapy, diarrhea recurred in all patients within 1–12 days, and responded to reinitiation of octreotide in those five patients who resumed treatment. Only one of the three patients with concurrent cryptosporidial infection responded to treatment. The drug was well tolerated, with mild symptomatology in three patients. Long-term treatment at a stable dose was effective in three of five treated patients for periods for seven months in one (moderate responder) and one year in two. One patient required dose increases to control symptoms, but after one year of treatment developed severe nausea following injections, which required dose cessation. One patient had partial control of his diarrhea for only three months despite two dose increases. These data suggest that octreotide may be of useful therapeutic value in HIV-associated diarrhea and that further studies are indicated.This study was supported by Sandoz Canada Inc.  相似文献   
66.
McGrath  HE; Liang  CM; Alberico  TA; Quesenberry  PJ 《Blood》1987,70(4):1136-1142
We have previously reported that lithium chloride (LiCl) stimulates the production of granulocyte-macrophage colony-forming cells (GM-CFC), pluripotent stem cells (CFU-S), and differentiated granulocytes, macrophages and megakaryocytes in murine Dexter marrow cultures and that this effect appears to be mediated indirectly by a radioresistant adherent marrow cell. In this study we have established that exposure of murine Dexter cultures to LiCl (4 mEq/L) causes an increase of colony-forming cell megakaryocytes (CFU-meg) over 1 to 6 weeks of culture in both supernatant (188% to 611%) and stromal phases (123% to 246%). Moreover, we have shown that lithium treatment of either irradiated (1,100 rad) or unirradiated stromal cells increased production of activities stimulating formation of megakaryocyte, granulocyte, macrophage, and mixed lineage colonies and proliferation of the factor-dependent cell line, FDC-P1. This FDC-P1 stimulatory activity was completely blocked by an antibody to purified recombinant granulocyte-macrophage colony stimulating factor (rGM-CSF). The baseline or lithium-induced--stromal-derived bone marrow colony stimulating activity was partially blocked by the antibody to rGM-CSF and by an antibody to purified colony stimulating factor I (CSF-1); the two antibodies combined resulted in greater than 90% inhibition of the lithium-induced marrow stimulatory activity. In addition, radioimmunoassay (RIA) showed that although CSF-1 was detectable in supernatants of these cultures, exposure to lithium did not increase CSF-1 levels. These data indicate that Dexter stromal cells produce CSF- 1 and GM-CSF and that lithium appears to exert its stimulatory effects on in vitro myelopoiesis by inducing production of GM-CSF.  相似文献   
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Vitamin D insufficiency is widespread, regardless of geographical location. It is particularly prevalent in the elderly and has far-ranging health consequences including: osteoporosis, falls, increased risk of cancer, and altered glucose and lipid metabolism. Increasing evidence strongly supports the benefits of vitamin D supplementation and also reveals that present recommendations are inadequate, especially for older individuals. Although additional studies are still needed to further optimize diagnostic and therapeutic approaches, physicians should consider prescribing cholecalciferol--at least 2000 international units (IU) per day--to all elderly patients. Oral cholecalciferol supplementation at that level is inexpensive, safe, and effective, and has great potential to improve the quality of life of the elderly.  相似文献   
70.
Potent TLR4-dependent cell activation by Gram-negative bacterial endotoxin depends on sequential endotoxin?protein and protein?protein interactions with LBP, CD14, MD-2 and TLR4. LBP and CD14 combine, in an albumin-dependent fashion, to extract single endotoxin molecules from purified endotoxin aggregates (E(agg)) or the bacterial outer membrane and form monomeric endotoxin:CD14 complexes that are the preferred presentation of endotoxin for transfer to MD-2. Endotoxin in endotoxin:CD14is readily transferred to MD-2, again in an albumin-dependent manner, to form monomeric endotoxin:MD-2 complex. This monomeric endotoxin:protein complex (endotoxin:MD-2) activates TLR4 at picomolar concentrations, independently of albumin, and is, therefore, the apparent ligand in endotoxin-dependent TLR4 activation. Tetra-, penta-, and hexa-acylated forms of meningococcal endotoxin (LOS) react similarly with LBP, CD14, and MD-2 to form endotoxin:MD-2 complexes. However, tetra- and penta-acylated LOS:MD-2 complexes are less potent TLR4 agonists than hexa-acylated LOS:MD-2. This is mirrored in the reduced activity of tetra-, penta- versus hexa-acylated LOS aggregates (LOS(agg)) + LBP toward cells containing mCD14, MD-2, and TLR4. Therefore, changes in agonist potency of under-acylated meninigococcal LOS are determined by differences in properties of monomeric endotoxin:MD-2.  相似文献   
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