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71.
D E Cutlip M B Leon K K Ho P C Gordon A Giambartolomei D J Diver D M Lasorda D O Williams M M Fitzpatrick A Desjardin J J Popma R E Kuntz D S Baim 《Journal of the American College of Cardiology》1999,34(3):698-706
OBJECTIVES: This registry collected the 30-day and 9-month clinical outcomes of patients whose coronary stent implantation was suboptimal, and compared them with the cohort of patients with "optimal" stenting in the randomized portion of the STent Anti-thrombotic Regimen Study (STARS) trial. BACKGROUND: Although "optimal" stenting combined with an aspirin and ticlopidine regimen carries a low (0.5%) incidence of subacute stent thrombosis, only limited data are available for patients in whom stents are deployed suboptimally. METHODS: In the STARS, 312 (15.9%) of 1,965 patients enrolled were excluded from participation in the randomized trial based on a perceived "suboptimal" result of coronary stenting. Of these, 265 patients met prespecified criteria for suboptimal stenting, and were followed in a parallel registry, which was compared with the randomized STARS optimal stenting cohort. The primary end point was a 30-day composite of death, emergent target lesion revascularization, angiographic thrombosis of the target vessel without revascularization and nonfatal myocardial infarction (MI) unrelated to direct procedural complications. RESULTS: Registry patients had a similar frequency of the primary end point compared with the overall randomized cohort (3.0% vs. 2.2%), with this end point correlating to use of multiple stents, smaller final lumen diameter and absence of ticlopidine from the poststent regimen. Overall 30-day mortality (1.1% vs. 0.06%, p = 0.009) and periprocedural non-Q wave MI (8.7% vs. 4.2%, p = 0.003) were more frequent in registry patients, and appeared to be related to acute procedural complications. Clinical restenosis was significantly higher for registry patients (26.8% vs. 16.0%, p = 0.001), relating to greater prevalence of independent predictors such as smaller final lumen diameter and multiple stent use. CONCLUSIONS: In the STARS registry, the inability to perform optimal stenting correlated with smaller final lumen diameter and longer stent length. With ticlopidine-containing regimens, the acute clinical results of "suboptimal" stent deployment are clinically acceptable, although they are not quite as good as those of optimal stenting using similar drug therapy. 相似文献
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T Bardin D Kuntz J Zingraff M C Voisin A Zelmar J Lansaman 《Arthritis and rheumatism》1985,28(9):1052-1058
Synovial amyloid deposits were found in 18 patients with end-stage renal failure due to various nonamyloid nephropathies, who had been treated with long-term, periodic hemodialysis (mean 116 months). All patients had carpal tunnel syndrome, which was bilateral in 14 of them; 4 patients also had finger flexor tenosynovitis. In 2 patients, destructive arthropathies required surgical replacement of the hip. Amyloid deposits were demonstrated by light microscopy in the synovium of the finger flexor tendon and/or transverse carpal ligament of all patients who had surgery for carpal tunnel syndrome, and in the synovium and capsula of the 2 surgically removed hips. Transmission electron microscopy of synovial samples from 6 patients demonstrated the characteristic fibrillar ultrastructure of amyloid deposits, the biochemical nature of which is still unknown. In addition, 9 patients had cystic radiolucencies of bone, which were interpreted as having resulted from local amyloid deposits, involving carpal bones, humeral heads, femoral heads, acetabula, or tibial plateaus. Our results show that amyloidosis is a frequent histologic finding in dialysis patients receiving surgical management of carpal tunnel syndrome, and that it can also be associated with cystic radiolucencies of bones and with destructive arthropathies. 相似文献
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Thrombopoietin (TPO) or MpI ligand is known to stimulate megakaryocyte (MK) proliferation and differentiation. To identify the earliest human hematopoietic cells on which TPO acts, we cultured single CD34+Thy- 1+Lin- adult bone marrow cells in the presence of TPO alone, with TPO and interleukin-3 (IL-3), or with TPO and c-kit ligand (KL) in the presence of a murine stromal cell line (Sys1). Two distinct growth morphologies were observed: expansion of up to 200 blast cells with subsequent differentiation to large refractile CD41b+ MKs within 3 weeks or expansion to 200-10,000 blast cells, up to 25% of which expressed CD34. The latter blast cell expansions occurred over a 3- to 6-week period without obvious MK differentiation. Morphological staining, analysis of surface marker expression, and colony formation analysis revealed that these populations consisted predominantly of cells committed to the myelomonocytic lineage. The addition of IL-3 to TPO-containing cultures increased the extent of proliferation of single cells, whereas addition of KL increased the percentage of CD34+ cells among the expanding cell populations. Production of multiple colony- forming unit-MK from single CD34+Thy-1+Lin- cells in the presence of TPO was also demonstrated. In limiting dilution assays of CD34+Lin- cells, TPO was found to increase the size and frequency of cobblestone areas at 4 weeks in stromal cultures in the presence of leukemia inhibitory factor and IL-6. In stroma-free cultures, TPO activated a quiescent CD34+Lin-Rhodamine 123lo subset of primitive hematopoietic progenitor cells into cycle, without loss of CD34 expression. These data demonstrate that TPO acts directly on and supports division of cells more primitive than those committed to the MK lineage. 相似文献
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An estimated 2 % to 5 % of all persons with multiple sclerosis (MS) have onset of symptoms before 16 years of age Krupp and Hertz (Neurology 68(Suppl 2), 2007). As in adults, the diagnosis of pediatric MS is a clinical one, requiring recurrent episodes of CNS demyelination with supportive paraclinical data (MRI findings, CSF characteristics) in the absence of another plausible diagnosis. The differential diagnosis is broad and, the more atypical the case and the younger the child, the more consideration is necessary before making a diagnosis of MS. MS must be differentiated from acute disseminated encephalomyelitis (ADEM) or neuromyelitis optica (NMO). After initial presentation with a CNS demyelinating event or clinically isolated syndrome (CIS), children can meet the diagnostic criteria for MS if serial changes are noted on MRI and other disorders are excluded. Accurate diagnosis of pediatric MS is critical because of the implications of the diagnosis, including the need for long-term disease modifying therapy. 相似文献