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991.
目的:观察分析肝移植术后急性肺损伤发生原因及处理措施。方法:选择2000-02/2005-05在解放军总医院第二附属医院接受原位肝移植患者130例,均签署手术知情同意书。术毕给予呼吸机控制呼吸,自主呼吸恢复后给予呼吸机辅助呼吸,平均6.8h脱呼吸机,之后双鼻导管吸氧3~10L。定时测定血气分析、肝功能、肾功能、血常规、凝血4项、血乳酸、血氨、电解质及血糖,每日做痰、胆汁、腹腔引流液培养。防治细菌感染,预防真菌及病毒感染。进行抗排斥反应、保肝、营养代谢支持、利尿与扩血管等综合治疗。结果:①肝移植受者130例术后48h内死亡3例,术后3~10d内死亡9例均并发肺部感染,存活病例发生肺部感染28例。存活118例发生急性肺损伤87例(占73.7%),经治疗后各脏器均恢复正常。②患者发生急性肺损伤时间多为术后两三天,其中29例发生急性呼吸窘迫综合征,大部分经加大吸氧浓度或面罩吸氧,增加氧气雾化吸入次数等综合救治措施均恢复。③术中出血量为2000~8000mL者共76例,发生急性肺损伤69例;术中出血量>8000mL者18例,术后均出现急性肺损伤。急性肺损伤与术后出量(尿量、T管、腹腔引流)关系比较大。④原发病为肝炎肝硬化肝功能失代偿患者急性肺损伤的发病率最高,显著高于原发病为慢性肝炎肝硬化肝癌患者(85%,39%,P<0.05)。结论:肝移植术后急性肺损伤发生与原发疾病、手术损伤、术中血流动力学不稳定、术后出量有一定关系。临床除氧疗外,应做好全身综合治疗。  相似文献   
992.
Hematopoietic reconstitution following syngeneic bone marrow transplantation with graded doses of untreated and drug-treated bone marrow was studied in B6D2F1 mice. Granulocyte-macrophage colony- forming units (CFU-GM) and spleen colony-forming units (CFU-S) showed similar in vitro drug sensitivities. Both the speed of hematologic recovery and survival of mice transplanted with untreated or drug- treated bone marrow were directly related to the number of CFU-GM or CFU-S transplanted. Similar hematologic recovery was seen for untreated marrow transplants and treated transplants that had similar CFU-GM or CFU-S content. There is a minimum number of transplanted CFU-GM or CFU- S that allows survival of lethally irradiated mice. This number is present in a marrow transplant containing the equivalent of 5 X 10(3) untreated cells or producing one to two spleen colonies. There also exists a maximum value for the number of hematopoietic progenitors in a marrow graft, above which the rate of hematologic recovery following transplantation is rapid and no detectable increase in the rate is seen with increasing CFU-GM or CFU-S content. The presence of this maximum value for transplanted progenitors and variations in culture techniques are probably the reasons previous studies have not always shown a correlation between CFU-GM content and hematologic recovery after bone marrow transplantation.  相似文献   
993.
Bruno  E; Cooper  RJ; Wilson  EL; Gabrilove  JL; Hoffman  R 《Blood》1993,82(2):430-435
Basic fibroblast growth factor (bFGF), a multifunctional growth factor produced by bone marrow stromal cells, is known to be a potent modulator of hematopoiesis. Because bFGF is present in both human megakaryocytes (MKs) and platelets, we have hypothesized that this growth factor might affect human megakaryocytopoiesis. To test this hypothesis, either low density bone marrow (BM) cells (LDBM), a human BM subpopulation (CD34+ DR+) enriched for the colony-forming unit megakaryocyte (CFU-MK) or a BM subpopulation (CD34+ DR-) enriched for the more primitive burst-forming unit megakaryocyte (BFU-MK) were assayed in the presence of this growth factor. The effect of bFGF on MK colony formation differed according to the cell population assayed. bFGF alone had on MK colony-stimulating activity (MK-CSA) when either CD34+ DR+ or CD34+ DR- BM cells were cloned, but exhibited MK-CSA equivalent to that of interleukin-3 (IL-3) when LDBM cells were used as the target cell population. The MK-CSA of bFGF was inhibited by the addition of neutralizing antisera to either IL-3 and/or granulocyte- macrophage colony-stimulating factor (GM-CSF) but not IL-6. The addition of excess amounts of either IL-3 or GM-CSF to cultures containing bFGF plus anti-IL-3 or anti-GM-CSF reversed the inhibition by the corresponding antisera. The addition of bFGF and IL-3 to assays containing CD34+ DR+ or CD34+ DR- cells increased the size of both CFU- MK- and BFU-MK-derived colonies, respectively, when compared with assays containing IL-3 alone. This increase in MK colony size mediated by bFGF was not affected by addition of either an anti-GM-CSF or anti- IL-6 neutralizing antisera. When LDBM cells were assayed, bFGF alone increased CFU-MK-derived colony size when compared with control values. However, this potentiation of MK colony size by bFGF could be reversed by the addition of either anti-IL-3 or anti-GM-CSF but not anti-IL-6 antisera. In addition, the effects of bFGF and IL-3 on the size of MK colonies cloned from LDBM were not additive. These results suggest that bFGF affects human megakaryocytopoiesis by directly promoting MK progenitor cell proliferation and stimulating BM accessory cells to release growth factor(s) with MK-CSA, such as IL-3 and GM-CSF. We conclude that bFGF, likely produced by cellular components of the BM microenvironment, plays an important role in the control of human megakaryocytopoiesis.  相似文献   
994.
995.
996.
We investigated whether the androgen type or application mode or testosterone (T) serum levels influence serum lipids and lipoprotein levels differentially in 55 hypogonadal men randomly assigned to the following treatment groups: mesterolone 100 mg orally daily ([MES] n = 12), testosterone undecanoate 160 mg orally daily ([TU] n = 13), testosterone enanthate 250 mg intramuscularly every 21 days ([TE] n = 15), or a single subcutaneous implantation of crystalline T 1,200 mg ([TPEL] n = 15). The dosages were based on standard treatment regimens. Previous androgen substitution was suspended for at least 3 months. Only metabolically healthy men with serum T less than 3.6 nmol/L and total cholesterol (TC) and triglyceride (TG) less than 200 mg/dL were included. After a screening period of 2 weeks, the study medication was taken from days 0 to 189, with follow-up visits on days 246 and 300. Before substitution, all men were clearly hypogonadal, with mean serum T less than 3 nmol/L in all groups. Androgen substitution led to no significant increase of serum T in the MES group, subnormal T in the TU group (5.7 +/- 0.3 nmol/L), normal T in the TE group (13.5 +/- 0.7 nmol/L), and high-normal T in the TPEL group (23.2 +/- 1.1 nmol/L). 5 alpha-Dihydrotestosterone significantly increased in all treatment groups compared with baseline. Compared with presubstitution levels, a significant increase of TC was observed in all treatment groups (TU, 14.4% +/- 3.0%; MES, 18.8% +/- 2.5%; TE, 20.4% +/- 3.0%; TPEL, 20.2% +/- 2.6%). Low-density lipoprotein cholesterol (LDL-C) also increased significantly by 34.3% +/- 5.5% (TU), 46.4% +/- 4.1% (MES), 65.2% +/- 5.7% (TE), and 47.5% +/- 4.3% (TPEL). High-density lipoprotein cholesterol (HDL-C) showed a significant decrease by -30.9% +/- 2.8% (TU), -34.9% +/- 2.5% (MES), -35.7% +/- 2.6% (TE), and -32.5% +/- 3.5% (TPEL). Serum TG significantly increased by 37.3% +/- 11.3% (TU), 46.4% +/- 10.3% (MES), 29.4% +/- 6.5% (TE), and 22.9% +/- 6.7% (TPEL). TU caused a smaller increase of TC than TE and TPEL, whereas the parenteral treatment modes showed a lower increase of TG. There was no correlation between serum T and lipid concentrations. Despite the return of serum T to pretreatment levels, serum lipid and lipoprotein levels did not return to baseline during follow-up evaluation. In summary, androgen substitution in hypogonadal men increases TC, LDL-C, and TG and decreases HDL-C independently of the androgen type and application made and the serum androgen levels achieved. Due to the extended washout period for previous androgen medication and the exclusion of men with preexisting hyperlipidemia, this investigation demonstrates more clearly than previous studies the impact of androgen effects on serum lipids and lipoproteins. It is concluded that preexisting low serum androgens induce a "male-type" serum lipid profile, and increasing serum androgens further within the male normal range does not exert any additional effects. The threshold appears to be above the normal female androgen serum levels and far below the lower limit of normal serum T levels in adult men. These findings may have considerable implications for the use of androgens as a male contraceptive and for androgen therapy in elderly men.  相似文献   
997.
This report presents the first year's experience of a totally computerized cardiac catheterization laboratory reporting system, including the results and complications of invasive and interventional procedures. Sixty-three laboratories reported a total of 71,916 patients studied between January 1 through December 31, 1990. Two previous registry reports have been published. Compared with data acquired by previous methods, in spite of an older and sicker population, the mortality for diagnostic procedures has remained remarkably constant (0.11%). The computerized format facilitates data collection and analysis, helps resolve new issues as they arise and serves as a method of monitoring quality of laboratories and individuals.  相似文献   
998.
In a 42-month period, 218 deaths occurred in 222,553 patients undergoing coronary arteriography (0.098%). Age greater than 60 years, NYHA Class IV function, presence of left main coronary disease, and ejection fraction less than 30% all significantly increased the risk of the procedure. Sex and approach (brachial or femoral) used for the catheterization did not affect mortality. Since the SCAI report in 1982, the death rate has dropped significantly in high-risk patients. Low-risk patients (NYHA Class I or normal coronary arteries) who died generally were elderly or had associated valvular heart disease.  相似文献   
999.
Pichert  G; Alyea  EP; Soiffer  RJ; Roy  DC; Ritz  J 《Blood》1994,84(7):2109-2114
Previous studies have shown that tumor-specific bcr-abl mRNA can often be detected by polymerase chain reaction. (PCR) for months to years after allogeneic bone marrow transplantation (BMT) for chronic myelocytic leukemia (CML). Nevertheless, the presence of bcr-abl mRNA by itself does not invariably predict for clinical relapse post-BMT. This has led to the hypothesis that bcr-abl mRNA might be expressed in cells that have lost either proliferative or myeloid differentiation potential. To directly characterize the cells detected by PCR in patients with CML after allogeneic BMT, we first identified five individuals in whom PCR-positive cells could be detected at multiple times post-BMT. Bone marrow samples from these individuals were cultured in vitro and single erythroid, granulocytic, and macrophage colonies, each containing 50 to 100 cells, were examined for the presence of bcr-abl mRNA by PCR. PCR-positive myeloid colonies could be detected in four of five individuals in marrow samples obtained 5 to 56 months post-BMT. Overall, 7 of 135 progenitor cell colonies (5.2%) were found to be PCR-positive. The expression of bcr-abl mRNA appeared to be equally distributed among committed erythroid, macrophage, and granulocyte progenitors. These patients have now been followed-up for an additional 20 to 33 months from the time of progenitor cell PCR analysis but only one of these individuals has been found to have cytogenetic evidence of recurrent Ph+ cells. These results show that long-term persistence of PCR-detectable bcr-abl mRNA after allogeneic BMT can be caused by the persistence of CML-derived clonogenic myeloid precursors that have survived the BMT preparative regimen. These cells continue to have both proliferative and myeloid differentiation capacity in vitro. Nevertheless, these PCR-positive cells do not appear to either expand or differentiate in vivo for prolonged periods, suggesting the presence of mechanisms for suppression of residual clonogenic leukemia cells in vivo.  相似文献   
1000.
The effect of re-feeding glucose, protein or fat and the effect of insulin injection on the activity of hepatic phosphoenolpyruvate carboxykinase (GTP: oxaloacetate carboxy-lyase (transphosphorylating) EC 4.1.1.32), the concentration of hepatic cyclic AMP and the level of serum insulin was investigated in starved rats. Under all conditions examined the concentration of serum insulin was elevated to a high degree. However, only rats re-fed with glucose responded to the increase in serum insulin with a decrease in PEP carboxykinase activity, while the activity of the enzyme remained unchanged or was elevated after re-feeding protein or fat or after insulin injection, respectively. Since under all conditions there was a close correlation between cyclic AMP concentration and PEP carboxykinase activity, but not between the insulin level and enzyme activity, it is concluded that the hormone physiologically regulates PEP carboxykinase activity by decreasing the intrahepatic cyclic AMP concentration rather than by the postulated cyclic AMP-independent inhibition of specific mRNA translation.  相似文献   
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