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Studies of circulating hemopoietic progenitor cells in human fetal blood   总被引:3,自引:0,他引:3  
Linch  DC; Knott  LJ; Rodeck  CH; Huehns  ER 《Blood》1982,59(5):976-979
High levels of committed erythroid and granulocytic/monocytic progenitor cells have been demonstrated in fresh blood obtained at fetoscopy. The fetal progenitor cells were more sensitive to appropriate stimuli (erythropoietin and colony-stimulating factor) than adult progenitor cells grown under the same conditions, and this was shown to be due to intrinsic differences in the progenitor cells at the different developmental stages.  相似文献   
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The more metastatic sites and bone marrow metastasis in small cell lung cancer (SCLC), the worse the prognosis. Diagnosing the bone marrow invasion at the beginning of the therapy is important for determining of the prognosis and planning the treatment. Abnormalities of some blood parameters may help to estimate the extent of bone marrow invasion by cancer cells. In this retrospective review, the changes in routine laboratory tests that may indicate bone marrow invasion, the predictive values of these tests, and the prognostic importance of bone marrow invasion were evaluated in SCLC patients who were being followed up according to a protocol. One hundred and forty‐four patients with SCLC were enrolled in this study. Retrospectively, it was evaluated that 25 (17.4%) of the patients had bone marrow metastasis. According to univariate analysis, there was a significant difference between hemoglobin, white blood cell count, platelet count, lactate dehydrogenase, alkaline phosphatase and uric acid of the patients with and without bone marrow involvement. Among the biochemical parameters, the elevated LDH and AP had the highest sensitivity and specificity as indicators of bone marrow invasion (0.80–0.82 and 0.84–0.78, respectively). The median overall survival of extensive‐stage disease with and without bone marrow metastasis were 4.0 ± 1.0 months (95% CI 2.2–5.7) and 7.0 ± 1.2 months (95% CI 4.7–9.3), respectively (P = 0.03). Bone marrow metastasis was found to be an indicator of a bad prognosis. Bone marrow biopsy, that is an invasive procedure, can be performed on selected patients who have changes of routine laboratory tests suggesting bone marrow invasion.  相似文献   
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BACKGROUND: Current practice guidelines for performance of percutaneous coronary intervention (PCI) in the United States mandate availability of on-site surgical backup. With the decreasing frequency of urgent coronary bypass surgery (UCABG) with newer technologies, it is unclear whether such backup continues to be necessary. METHODS: A database of 5655 consecutive patients undergoing PCI at a single center between August 1, 1992, and December 31, 1997, was analyzed. Outcomes were determined as well as clinical, lesion, and procedural characteristics of patients during 4 time periods preceding and during use of coronary stenting. RESULTS: Frequency of UCABG for failed PCI decreased from 2.2% to 0.6% in the most recent time period (P <.01) with no change in incidence of in-hospital death or myocardial infarction. Incidence of stenting progressively increased to 72% in the latest period. Patients requiring UCABG had a higher prevalence of acute coronary syndromes (95%) and type B lesions (79%), but these characteristics were also common in patients who did not undergo UCABG. Although coronary stents were available during the last 3 periods studied, only 30% of UCABG patients had lesions or complications amenable to stenting, and stenting attempts in these patients were all unsuccessful. Despite stenting and use of perfusion balloons and intra-aortic balloon pumps, only 40% of patients having UCABG were stable and pain free on transfer to the operating room. CONCLUSIONS: Although use of UCABG for a failed PCI is currently very low, there are no satisfactory predictors, patients requiring UCABG are frequently clinically unstable, and availability of stenting does not reliably eliminate the need for UCABG or result in a decrease in mortality. This small group of patients continues to require readily available surgical standby.  相似文献   
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