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111.
O'Shaughnessy JA; Venzon DJ; Gossard M; Noone MH; Denicoff A; Tolcher A; Danforth D; Jacobson J; Keegan P; Miller L 《Blood》1995,86(8):2913-2921
Cumulative thrombocytopenia is a dose-limiting toxicity of dose- intensive chemotherapy for advanced breast cancer. In this phase I study, we have studied the hematologic toxicity associated with sequential interleukin-3 (IL-3) and granulocyte-macrophage colony- stimulating factor (GM-CSF; molgramostim) administration after multiple cycles of FLAC (5-fluorouracil, leucovorin, doxorubicin, cyclophosphamide) chemotherapy compared with that after concurrent cytokine administration or to each cytokine administered alone. Ninety- three patients with advanced breast cancer were treated with five cycles of FLAC chemotherapy and either IL-3 alone, GM-CSF alone, sequential IL-3 and GM-CSF administered by schedule A (5 days of IL-3 followed by 10 days of GM-CSF) or schedule B (9 days of IL-3 followed by 6 days of GM-CSF), or concurrent administration of IL-3 and GM-CSF for 15 days. Cohorts of patients were treated with one of four dose levels of IL-3 (1,2.5, 5, and 10 micrograms/kg) administered subcutaneously for each schedule of cytokine administration. The GM-CSF dose in all schedules was 5 micrograms/kg/day. Sequential IL-3 and GM- CSF (schedule B) was associated with higher platelet nadirs, shorter durations of platelet counts less than 50,000/microL, and the need for fewer platelet transfusions over five cycles of FLAC chemotherapy compared with concurrent cytokines, sequential IL-3 and GM-CSF schedule A, and GM-CSF alone. Concurrent IL-3 and GM-CSF was associated with unexpected platelet toxicity. The duration of granulocytopenia after FLAC chemotherapy was significantly worse with IL-3 alone compared with each of the GM-CSF-containing cytokine regimens. Although no cycle 1 maximum tolerated dose for IL-3 was defined in this study, 5 micrograms/kg was well tolerated over multiple cycles of therapy and is recommended for future studies. The data from this phase I study suggest that sequential IL-3 and GM-CSF with IL-3 administered for 9 days before beginning GM-CSF may be superior to shorter durations of IL- 3 administered sequentially with GM-CSF, to concurrent IL-3 and GM-CSF, and to either colony-stimulating factor alone in ameliorating the cumulative hematologic toxicity associated with multiple cycles of FLAC chemotherapy. Additional studies of sequential IL-3 and GM-CSF are warranted. 相似文献
112.
Thrombopoietin (c-Mpl ligand) has recently been purified and is considered to be the humoral regulator of platelet production. To see whether this molecule possessed the physiologic characteristics necessary to mediate the feed-back loop between blood platelets and the bone marrow megakaryocytes, we determined the relationship between blood levels of thrombopoietin and changes in the circulating platelet mass. We developed a model of nonimmune thrombocytopenia in rabbits by the subcutaneous administration of busulfan. Compared with pretreatment plasma, plasma taken from all thrombocytopenic rabbits at their platelet nadir contained increased amounts of thrombopoietin. All of this activity was neutralized by soluble c-Mpl receptor. We subsequently measured the level of thrombopoietin in the circulation over the entire time course after the administration of busulfan. As the platelet mass declined, levels of thrombopoietin increased inversely and proportionally and peaked during the platelet nadir. With return of the platelet mass toward normal, thrombopoietin levels decreased accordingly. When platelets were transfused into thrombocytopenic rabbits near the time of their platelet count nadir, the elevated levels of thrombopoietin decreased. In addition, platelets were observed to remove thrombopoietin from thrombocytopenic plasma in vitro. These results confirm that thrombopoietin is the humoral mediator of megakaryocytopoiesis and suggest that the platelet mass may directly play a role in regulating the circulating levels of this factor. 相似文献
113.
This report describes the production and characterization of 13 rodent monoclonal antibodies to the human erythrocyte anion transport protein AE1 (syn. band 3). Eleven antibodies (4 murine and 7 rat) recognize epitopes dependent on the integrity of the third extracellular loop of the protein. Two antibodies (1 murine and 1 rat) recognize epitopes on the N-terminal cytoplasmic domain. Quantitative binding studies using radioiodinated IgG and Fab fragments of antibodies to extracellular epitopes on AE1 ranged from 77,000 to 313,000 (IgG) and from 241,000 to 772,000 (Fab) molecules bound at saturation. The results indicate that the epitopes recognized by different antibodies vary in their accessibility and suggest that there is heterogeneity in the organization of individual AE1 molecules in the red blood cell membrane. Quantitative binding studies on South East Asian ovalocytes using several antibodies to AE1 and an anti-Wrb show a marked reduction in the number of antibody molecules bound at saturation. These results are consistent with the existence of highly cooperative interactions between transmembrane domains of AE1 in normal erythrocytes and the disruption of these interactions in the variant AE1 found in South East Asian ovalocytes. 相似文献
114.
Weisdorf DJ; Verfaillie CM; Davies SM; Filipovich AH; Wagner JE Jr; Miller JS; Burroughs J; Ramsay NK; Kersey JH; McGlave PB 《Blood》1995,85(12):3452-3456
Delay in hematologic recovery after bone marrow transplantation (BMT) can extend and amplify the risks of infection and hemorrhage, compromise patients' survival, and increase the duration and cost of hospitalization. Because current studies suggest that granulocyte- macrophage (GM) colony-stimulating factor (CSF) may potentiate the sensitivity of hematopoietic progenitor cells to G-CSF, we performed a prospective, randomized trial comparing GM-CSF (250 micrograms/m2/d x 14 days) versus sequential GM-CSF x 7 days followed by G-CSF (5 micrograms/kg/d x 7 days) as treatment for primary or secondary graft failure after BMT. Eligibility criteria included failure to achieve a white blood cell (WBC) count > or = 100/microL by day +21 or > or = 300/microL by day +28, no absolute neutrophil count (ANC) > or = 200/microL by day +28, or secondary sustained neutropenia after initial engraftment. Forty-seven patients were enrolled: 23 received GM-CSF (10 unrelated, 8 related allogeneic, and 5 autologous), and 24 received GM- CSF followed by G-CSF (12 unrelated, 7 related allogeneic, and 5 autologous). For patients receiving GM-CSF alone, neutrophil recovery (ANC > or = 500/microL) occurred between 2 and 61 days (median, 8 days) after therapy, while those receiving GM-CSF+G-CSF recovered at a similar rate of 1 to 36 days (median, 6 days; P = .39). Recovery to red blood cell (RBC) transfusion independence was slow, occurring 6 to 250 days (median, 35 days) after enrollment with no significant difference between the two treatment groups (GM-CSF: median, 30 days; GM-CSF+G- CSF; median, 42 days; P = .24). Similarly, platelet transfusion independence was delayed until 4 to 249 days (median, 32 days) after enrollment, with no difference between the two treatment groups (GM- CSF: median, 28 days; GM-CSF+G-CSF: median, 42 days; P = .38). Recovery times were not different between patients with unrelated donors and those with related donors or autologous transplant recipients. Survival at 100 days after enrollment was superior after treatment with GM-CSF alone. Only 1 of 23 patients treated with GM-CSF died versus 7 of 24 treated with GM-CSF+G-CSF who died 16 to 84 days (median, 38 days) after enrollment, yielding Kaplan-Meier 100-day survival estimates of 96% +/- 8% for GM-CSF versus 71% +/- 18% for GM-CSF+G-CSF (P = .026). These data suggest that sequential growth factor therapy with GM-CSF followed by G-CSF offers no advantage over GM-CSF alone in accelerating trilineage hematopoiesis or preventing lethal complications in patients with poor graft function after BMT.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
115.
Two hundred and sixteen patients with non-insulin-dependent diabetes
(NIDDM) and 216 age- and gender-matched controls were studied to assess the
prevalence of limited joint mobility (LJM). Joint mobility was measured by
goniometry at metacarpophalangeal and subtalar joints, and those in whom a
prayer sign was elicited were said to have cheiroarthropathy. Forty
diabetic patients and 10 controls had cheirorathropathy. The mean range of
motion was reduced at metacarpophalangeal joints in diabetic patients with
cheiroarthropathy (36.8 +/- 9.2) and without cheiroarthropathy (45.7 +/-
8.1) when compared to controls (51.4 +/- 9, P < 0.01). Mobility at
subtalar joints was reduced in those with cheiroarthropathy (25 +/- 5.3, P
< 0.01) when compared to controls (32.4 +/- 4.1) and diabetic patients
without cheiroarthropathy (27.4 +/- 4.6). No differences in subtalar
mobility existed between diabetic patients without cheiroarthropathy and
controls. Significant differences were observed in the presence of foot
ulceration (35 vs 16%) in those with and without cheiroarthropathy. We
conclude that cheiroarthropathy is seen in Sri Lankan patients with NIDDM
and that significant limitation of joint mobility is present in patients
with NIDDM who do not have overt cheiroarthropathy and that overt
cheiroarthropathy may be a marker for a high risk of foot ulceration.
相似文献
116.
胃癌病因:人N-亚硝酰胺暴露 总被引:13,自引:6,他引:13
胃癌死亡率居我国恶性肿瘤之首.其危险因素包括:①化学因素,如胃内合成的亚硝基化合物(NOC)和高盐饮食;②生物因素,如幽门螺杆菌感染和摄入生物毒素;③营养因素,如维生素C、硒和其他抗氧化剂等缺乏.NOC的胺类前体物和亚硝化剂(亚硝酸根和各种氧化氮)广泛存在于人体内外环境中,研究发现NOC暴露,可能与上消化道肿瘤的发生有关.高盐饮食和某些微量营养素缺乏,则能够增强NOC的致癌性.幽门螺杆菌感染与胃腺癌发生的关系尚未确定,但与胃粘膜相关性淋巴样组织淋巴瘤(MALT)的存在关系密切,机制不明.已知感染该菌能引发萎缩性胃炎和胃酸缺乏,间接促进NOC胃内合成.可见,NOC是多种胃癌高危因素的作用靶点,是证据最多的诱发胃癌因素. 相似文献
117.
A retrospective analysis was made of the data on 60 patients with stage T1 glottic carcinoma (43 T1a, 17 T1b) who received radiation therapy and 17 patients with T1a disease who underwent laser excision as the primary treatment modality. Patients who received radiation therapy achieved 3- and 5-year actuarial local control rates of 92% and 89% for T1a and 77% and 77% for T1b disease, respectively. In patients who underwent laser excision (all with T1a disease), the 3-year local control rate was 77%. Of the 42 evaluable irradiated T1a patients, 31 (74%) had a normal to near-normal voice, eight (19%) had mild or intermittent hoarseness, and three (7%) had persistent hoarseness. Of the 13 evaluable patients in the laser-excision group, four (31%) had a normal to near-normal voice, five (38%) had mild or intermittent hoarseness, and four (31%) had persistent hoarseness. The difference in the quality of voice between these two groups is statistically significant (P = .012), although the ultimate local control rate after salvage therapy for irradiated patients (97%) was similar to that for laser-excision patients (94%). 相似文献
118.
119.
Krutchen AE; Bjarnason H; Stackhouse DJ; Nazarian GK; Magney JE; Hunter DW 《Radiology》1996,200(1):159
120.
ST O'Sullivan MD FRCSI GT McGreal FRCS CM Reardon FRCSI DJ Hehir MCH FRCSI WO Kirwan MCH FRCSI MP Brady MCH FRCSI 《International journal of clinical practice》1997,51(5):289-292
During a four-year period, 308 patients presented following ingestion of foreign bodies. Ingestion was accidental in 272 cases (88.3%) and deliberate in the remainder. Symptoms at presentation included dysphagia, odynophagia, nausea and vomiting, chest pain and pharyngeal discomfort. Sixty-eight patients were asymptomatic. A policy of expectant management and selective endoscopy was employed. Following initial assessment 202 patients (65.6%) were discharged without treatment, 30 (9.7%) of whom were later reviewed as outpatients and did not require admission. Forty-nine patients (16%) were admitted for treatment; 27 had oesophagoscopy, five bronchoscopy and two had foreign body extraction with direct laryngoscopy. In nine patients who were endoscoped, no foreign body was identified. Twenty-seven others were referred to the otorhinolaryngology service in another hospital. There were no deaths in the group and morbidity was 1.2%. We conclude that a policy of selective endoscopy is safe and effective in the management of patients following ingestion of foreign bodies. 相似文献