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21.
Virally inactivated, high-purity factor XI concentrates are available for treatment of patients with factor XI deficiency. However, preliminary experience indicates that some preparations may be thrombogenic. We evaluated whether a highly purified concentrate produced signs of activation of the coagulation cascade in two patients with severe factor XI deficiency infused before and after surgery. Signs of heightened enzymatic activity of the common pathway of coagulation (elevated plasma levels of prothrombin fragment 1 + 2 and fibrinopeptide A) developed in the early post-infusion period, accompanied by more delayed signs of fibrin formation with secondary hyperfibrinolysis (elevated D-dimer and plasmin-antiplasmin complex). These changes occurred in both patients, but were more severe in the older patient with breast cancer when she underwent surgery, being accompanied by fibrinogen and platelet consumption. There were no concomitant signs of heightened activity of the factor VII-tissue factor mechanism on the factor Xase complex (plasma levels of activated factor VII and of factor IX and X activation peptides did not increase). The observed changes in biochemical markers of coagulation activation indicate that concentrate infusions increased thrombin generation and activity and that such changes were magnified by malignancy and surgery. Because some factor XI concentrates may be thrombogenic, they should be used with caution, especially in patients with other risk factors for thrombosis.  相似文献   
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23.
目的分析先天性肠闭锁病例的诊断及治疗,以提高治愈率及术后生活质量。方法回顾性分析166例先天性肠闭锁的临床资料。结果治愈142例,治愈率85.5%(142/166),其中包括18例二期手术治愈者;术中10例、术后8例放弃治疗;术后死亡6例。结论早期诊断和选择合理的术式是提高肠闭锁治愈率的关键,基础支持及手术技术改进能促进病情的恢复,改善预后。  相似文献   
24.
Analogues of oxytocin and deaminooxytocin with 4-glutamine replaced by 4-glutamic acid methyl ester readily lose their uterotonic activity when incubated with rat serum, presumably by hydrolysis to the much less active 4-glutamic acid derivatives. On the other hand, inactivation of the deaminooxytocin analogue in the rat uterus, as demonstrated by the 'oil-bath'technique, is only slightly more rapid than that of deaminooxytocin and distinctly slower than that of oxytocin. Its in situ/in vitro ratio of uterotonic activity is less than 0.1 whereas that for deaminooxytocin is about 3 and also the persistence of the uterotonic effect in situ is slightly less than that of deaminooxytocin. The results with these 'rapidly inactivated'analogues can be used as proof of some predictions of the three-compartment model for tissue distribution of neurohypophysial hormones and its influence upon the time course of a biological response published earlier. The potential use of analogues of neurohypophysial hormones as probes for inactivation mechanisms and the results thus far obtained are discussed.  相似文献   
25.
Foon  KA; Nakano  GM; Koller  CA; Longo  DL; Steis  RG 《Blood》1986,68(1):297-300
Two patients with hairy cell leukemia with massive splenomegaly and severe pancytopenia were treated with recombinant alpha-A interferon (IFN-alpha-2a). There was no significant response to a trial of IFN- alpha-2a (11 and 20 weeks) with respect to blood counts or spleen size. Subsequent treatment with 2'-deoxycoformycin (dCF) for 8 consecutive weeks (4 mg/m2/wk) resulted in normalization of spleen size and a normalization of peripheral blood counts and bone marrow in one patient. The second patient demonstrated a reduction in spleen size and improved blood counts following 9 weeks of dCF therapy but eventually became refractory. This demonstrates that dCF is non-cross-resistant with interferon and confirms the efficacy of dCF in nonsplenectomized patients.  相似文献   
26.
Relatively nonmyelotoxic drugs and drug combinations were investigated for their ability to eliminate malignant cells from human bone marrow. In vitro 90% inhibitory concentration (IC90) doses were established on granulocyte macrophage colony-forming units (GM-CFU) in culture of bone marrow by using the GM-CFU assay for the following drugs: 4- hydroperoxycyclophosphamide (4-HC), Adriamycin, L-asparaginase, bleomycin, hydrocortisone, VP-16, spirogermanium, Taxol, and vincristine. The leukemic cell kill efficiency of these drugs at IC90 doses was compared with that of 4-HC on acute lymphoid leukemia (ALL) cell lines by using the limiting-dilution assay. Under these conditions, no single drug was superior to 4-HC. To increase the in vitro effect in leukemic cell kill, combinations of vincristine with hydrocortisone, Adriamycin, VP-16, and 4-HC were investigated. Vincristine at 1 to 5 micrograms/mL increased the marrow cytotoxicity of hydrocortisone, Adriamycin, and VP-16, but it was protective (subadditive) with 4-HC. Vincristine and 4-HC in combination was additive to supraadditive on ALL cell lines, increased the leukemic cell kill by one to two logs above 4-HC alone at IC90 doses (P less than .05), and was not affected by the addition of excess marrow cells. The recommended doses for chemopurging in clinical studies are vincristine, 1 to 5 micrograms/mL, plus 4-HC, 5 micrograms/mL.  相似文献   
27.
A phase I clinical trial was initiated to treat patients with stage IV B-derived chronic lymphocytic leukemia (CLL) with the IgG2a murine monoclonal antibody T101. This antibody binds to a 65,000-mol wt (T65) antigen found on normal T lymphocytes, malignant T lymphocytes, and B- derived CLL cells. All of the patients had a histologically confirmed diagnosis of advanced B-derived CLL and were refractory to standard therapy, and more than 50% of their leukemia cells reacted with the T101 antibody in vitro. The patients received T101 antibody two times per week, over two to 50 hours by intravenous administration in 100 mL of normal saline containing 5% human albumin. Twelve patients were treated with a fixed dosage of 1, 10, 50, or 100 mg, and one patient was treated with 140 mg of antibody. It was demonstrated that patients given two-hour infusions of 50 mg developed pulmonary toxicity, with shortness of breath and chest tightness. This toxicity was eliminated when infusions of 50 or 100 mg of T101 were prolonged to 50 hours. All dose levels caused a rapid but transient decrease in circulating leukemia cell counts. In vivo binding to circulating and bone marrow leukemia cells was demonstrated at all dose levels with increased binding at higher dosages. Antimurine antibody responses were not demonstrated in any patients at any time during treatment. Circulating free murine antibody was demonstrated in the serum of only the two patients treated with 100 mg of antibody as a 50-hour infusion and the patient treated with 140 mg of antibody over 30 hours. Antigenic modulation was demonstrated in patients treated at all dose levels but was particularly apparent in patients treated with prolonged infusions of 50 and 100 mg of antibody. We were also able to demonstrate antigenic modulation in lymph node cells, which strongly suggests in vivo labeling of these cells. Overall, T101 antibody alone appears to have a very limited therapeutic value for patients with CLL. The observations of in vivo labeling of tumor cells, antigenic modulation, antibody pharmacokinetics, toxicity, and antimurine antibody formation may be used in the future for more effective therapy when drugs or toxins are conjugated to the antibody.  相似文献   
28.
The communication between tumor stromal and parenchymal cells provides an insight to tumor progression. One of the main elements of the stroma, a major contributor to the extracellular environment of tumors, is carcinoma‐associated fibroblasts. They can originate from either normal fibroblasts in the immediate vicinity of the tumor or from circulating bone marrow–derived mesenchymal stem cells. These myofibroblasts can arise locally from an endothelial–mesenchymal transformation at the invasive edge of the cancer and are physically associated with carcinoma cells, that is, in the development of high‐grade malignancies and poor prognosis. These carcinoma‐associated fibroblasts feed the epithelial tumor cells in a host–parasite relationship establishing its role in head and neck squamous cell carcinoma progression.  相似文献   
29.
目的初步探讨化疗联合HLA不全相合G-PBSC输注(微移植)治疗恶性血液病的临床应用。方法回顾性分析2015-05~2016-12接受微移植治疗的13例恶性血液病患者的临床及随访资料。根据病情,对13例患者行不同的预处理方案化疗后,计划给予微移植3~4次。观察微移植后患者的缓解情况,生存时间,血象恢复时间,急、慢性移植物抗宿主病(GVHD)及其他不良反应发生情况。结果随访至2017-04,中危组8例,其中存活6例,死亡2例;高危组5例,其中存活2例,死亡3例。中位生存期为9个月(4~24个月)。微移植治疗后,中性粒细胞和血小板平均恢复时间分别为8 d(5~14 d)和11 d(6~20 d)。所有患者在微移植过程中均未出现急、慢性GVHD及其他不良反应。结论微移植在供者选择上不受限制,移植后血小板及中性粒细胞恢复较快,且无急、慢性GVHD及其他不良反应发生;微移植在中高危恶性血液病的临床应用尚处于探索阶段,仍需多中心、大样本的临床研究来进一步验证。  相似文献   
30.
目的 研究中药燕滨扶正胶囊治疗肝硬化(代偿期或失代偿期)临床疗效。方法 选择代偿期及失代偿期肝硬化患者41例,随机分为治疗组(21例)及对照组(20例)。治疗组给予燕滨扶正胶囊1500 mg/次,口服,2次/日。对照组给予扶正化瘀胶囊2500 mg/次,3次/日。两组疗程均为48周。两组依据病情给予抗病毒,护肝降酶、对症支持等一般治疗(替比夫定、甘利欣、消炎利胆片、茵栀黄胶囊等),观察两组患者症状、血常规、肝功能、门静脉宽度、腹水、肝脏及脾脏形态。结果 中药燕滨扶正胶囊联合抗病毒药物可使代偿期及失代偿期肝硬化患者门静脉宽度、脾肿大回缩或复常,可使纤维化指标复常或大幅下降且肝脏功能好转或复常。结论 燕滨扶正胶囊可改善肝硬化。  相似文献   
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