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排序方式: 共有357条查询结果,搜索用时 15 毫秒
101.
A Rosemary Tate Alexander GR Martin Tarita Murray-Thomas Sarah R Anderson Jackie A Cassell 《BMC medical research methodology》2009,9(1):42-9
Background
Studies of cancer incidence and early management will increasingly draw on routine electronic patient records. However, data may be incomplete or inaccurate. We developed a generalisable strategy for investigating presenting symptoms and delays in diagnosis using ovarian cancer as an example. 相似文献102.
Nonneoplastic hematopoietic myeloproliferative syndrome induced by dysregulated multi-CSF (IL-3) expression 总被引:16,自引:2,他引:16
Post 5-fluorouracil-treated murine marrow cells were infected with a retroviral vector (MPZen) bearing a multi-potential colony stimulating factor (Multi-CSF) cDNA insert and then transplanted into lethally irradiated syngeneic recipients to study the effects of autocrine production of Multi-CSF in normal hematopoietic cells. Extremely high levels (14,000 U/mL) of Multi-CSF were detected in the sera and in media conditioned by various hematopoietic tissues of the transplanted animals. While spleen, peritoneal, and peripheral blood cellularity increased approximately 10-fold, 10-fold, and 50-fold, respectively, bone marrow cellularity decreased twofold. Progenitor numbers were depressed twofold in the bone marrow but elevated more than 100-fold in the spleen and peritoneum. The majority (80%) of transplanted mice died within 5 weeks of transplantation and showed extensive neutrophilic infiltration of the spleen, lung, liver, and muscle, often with mast cell foci; a phenomenon also seen in the skin and intestine. Neither the infected cells from hematopoietic tissues of the primary mice, nor autonomous mast cell-lines that grew from these cells in liquid culture produced any overt disease when transplanted into normal or sublethally irradiated secondary recipients. In contrast, injection into mice of autonomous FDC-P1 cells transformed by the same retroviral construct led to tumor formation in vivo within 4 weeks. Thus, dysregulated Multi- CSF expression by normal hematopoietic cells produces a fatal but nonneoplastic myeloproliferative syndrome. 相似文献
103.
Extracellular adenosine triphosphate increases cation permeability of chronic lymphocytic leukemic lymphocytes 总被引:5,自引:1,他引:5
Extracellular adenosine triphosphate (ATP) is known to reversibly increase the cation permeability of a variety of freshly isolated and cultured cell types. In this study the effects of extracellular ATP were studied using peripheral blood lymphocytes (PBL) isolated from both normal subjects and from patients with chronic lymphocytic leukemia (CLL). Changes in the permeability to Na+, Rb+, and Li+ ions were measured using conventional isotope and flame photometry techniques. In addition, changes in cytosolic (Ca2+) were fluorimetrically monitored to assess possible changes in net Ca2+ influx. ATP produced a 12-fold increase in 22Na+ influx into CLL cells but only a 3.5-fold increase in this flux in PBL cells. A maximal response was produced by 0.1 mmol/L ATP in the absence of Mg2+, while a twofold molar excess of Mg2+ over ATP abolished the response. ATP had no effect on the passive (ouabain-insensitive) 86Rb+ influx into PBL cells but stimulated this flux by fivefold in the CLL cells. Li+ influx into CLL cells was also stimulated threefold by ATP. Under these same conditions ATP also produced a net increase in total cell Na and a decrease in total cell K in the CLL cells. Exclusion of two normally impermeable dyes, trypan blue and ethidium bromide, was not altered in the ATP-treated CLL cells. Finally, extracellular ATP (3 mmol/L) produced no significant change in the cytosolic (Ca2+) of normal, monocyte-depleted populations of PBL. Conversely, this same concentration of ATP produced a very rapid (complete within 30 seconds) and a significant (an average threefold peak change) increase in the cytosolic (Ca2+) of cell preparations derived from five out of nine CLL patients. In these latter CLL cells, the ATP-induced elevation in cytosolic (Ca2+) appeared to be due to a net increase in Ca2+ influx, since no elevations were observed when the extracellular (Ca2+) was reduced to less than 0.1 mmol/L. These actions of ATP were specific in that equimolar concentrations of other nucleotides were without effect. These data indicate that treatment of CLL lymphocytes with extracellular ATP4 produces large increases in cation permeability. In contrast, there is less or no ATP-induced permeabilization of normal PBL. 相似文献
104.
Expression of a dominant interfering mutant of MAP kinase kinase (MAPKK) inhibits interleukin-3 (IL-3) activation of MAP kinase in the murine bone marrow-derived cell line BAF3. This results in an increase in the level of IL-3 required to stimulate cell proliferation and suppress apoptosis. When apoptosis is constitutively inhibited by coexpression of bcl-2, the dominant interfering MAPKK inhibits IL-3 driven cell cycle progression. Thus, MAPKK function is necessary for optimal IL-3 inhibition of apoptosis and optimal IL-3 stimulation of entry into S phase. Expression of a constitutively activated mutant of MAPKK does not replace IL-3, but renders cells able to proliferate in a density-dependent manner. Cell contact is required to allow cell proliferation; such contact can be supplied by cells without activated MAPKK. 相似文献
105.
Kremer E; Baker E; D'Andrea RJ; Slim R; Phillips H; Moretti PA; Lopez AF; Petit C; Vadas MA; Sutherland GR 《Blood》1993,82(1):22-28
The receptors for interleukin-3 (IL-3), IL-5, and granulocyte- macrophage colony-stimulating factor (GM-CSF) are heterodimers comprised of ligand specific alpha chains and a common beta chain. The genes encoding the IL-5 receptor alpha chain and the common beta chain reside on chromosome 3 and 22 respectively, while the GM-CSF receptor alpha chain gene (CSF2RA) has been mapped to the pseudoautosomal region (PAR) of the sex chromosomes, which is a 2.6-Mb stretch of homologous sequence at the tips of the short arms within which a single obligatory recombination occurs during male meiosis. We have mapped the gene encoding the IL-3 receptor alpha chain (IL3RA) to the sex chromosomes by polymerase chain reaction (PCR) analysis of human-mouse or human- chinese hamster cell hybrids, and to Yp13.3 and Xp22.3 using fluorescence in situ hybridization. To explore the possibility that IL3RA is located within the pseudoautosomal region we screened the Centre d'Etude du Polymorphisme Humain (CEPH) pedigrees for an informative-restriction fragment-length polymorphism (RFLP) that showed male meiotic recombination. Two informative CEPH pedigrees were identified that displayed this phenomenon, confirming the psuedoautosomal location of IL3RA. Using long-range restriction mapping we have found that IL3RA maps to the same 190-kb restriction fragment as CSF2RA, suggesting that a cytokine receptor gene cluster may reside in the PAR. 相似文献
106.
We have examined the in vivo radioprotective effects of the macrocyclic lactone protein kinase C (PK-C) activator, bryostatin 1, administered either alone or in conjunction with recombinant murine granulocyte- macrophage colony-stimulating factor (rmGM-CSF), in Balb/c and C3H/HeN mice subjected to lethal total body irradiation (TBI). When administered alone on a divided dose schedule (24 hours and 30 minutes before TBI), rmGM-CSF (20 micrograms/kg) was ineffective in increasing survival in either strain. However, in Balb/c mice, bryostatin 1 alone (1 microgram) permitted the long-term survival (60 days) of 70% of the animals following TBI, and 80% when administered in conjunction with rmGM-CSF. Bryostatin 1 administered alone according to this schedule exerted minimal radioprotective effects in C3H/HeN mice, but, when combined with a subeffective dose of rmGM-CSF, allowed 50% of the animals to survive. Treatment of Balb/c mice with bryostatin 1 administered as a single dose 4 hours before TBI resulted in a 20% survival rate, and 45% when administered with rmGM-CSF; corresponding values for the C3H/HeN strain were 60% and 40%, respectively. Lastly, the survival rates of Balb/c mice treated with bryostatin 1 administered as a single dose 4 hours following TBI was 20%, and 25% with rmGM-CSF; corresponding values were 50% and 25% for C3H/HeN mice. These findings indicate that the PK-C activator bryostatin 1 exhibits intrinsic in vivo radioprotective effects in lethally irradiated Balb/c and C3H/HeN mice, and may, under some circumstances, augment the radioprotective capacity of rmGM-CSF. They also underscore the critical role that strain differences and scheduling considerations play in determining the in vivo radioprotective capacity of bryostatin 1, as well as its interactions with rmGM-CSF. 相似文献
107.
Williamson LM; Wimperis JZ; Williamson P; Copplestone JA; Gooi HC; Morgenstern GR; Norfolk DR 《Blood》1994,83(10):3028-3035
To test the efficacy of poststorage bedside leucodepletion of blood products in the prevention of primary HLA alloimmunization and its clinical sequelae, 172 patients with hematologic malignancy requiring intensive red blood cell and platelet support were randomized to receive either standard or filtered red blood cells and platelets. Quality control of bedside filtration was explored by sequential sampling downstream of the filter, but this did not predict the total number of leucocytes transfused. After exclusions, 123 evaluable patients were assessed every two weeks until the end of therapy. HLA antibodies developed in 21 of 56 (37.5%) nonfilter (NF) and 15 of 67 (22%) filter (F) patients (risk ratio estimate, 0.60 [95% confidence interval, 0.34 to 1.05]; P = .07). Patients with acute myeloid leukemia (AML; n = 53) had higher alloimmunization rates in both arms of the study, with a greater effect of filtration (62.5% NF and 31.0% F; P = .025). Bedside filtration did not affect the overall incidence of febrile transfusion reactions (FTRs; 37% NF and 34% F; P = .71) or of platelet refractoriness assessed in 50 patients (30% NF and 26% F), despite an association between broad HLA reactivity and both FTRs and refractoriness. However, FTRs were also seen in 28 patients without HLA antibodies. Five alloimmunized refractory patients (2 F and 3 NF) required HLA-selected platelets. This report, the first prospective study of bedside filtration, has failed to show clear clinical benefit. Methodological limitations may account in part for this failure, notably the difficulties in accurately assessing the number of leucocytes transfused. 相似文献
108.
GR Velloso MM de Freitas ATNN Alves ARS Silva ESP Barboza V Moraschini 《Australian dental journal》2017,62(4):528-533
Invasive multiple cervical root resorptions after vital tooth bleaching is a rare condition. The aim of this article is to present a case of multiple external cervical root resorptions (ECRR) after a misguided home whitening treatment. A 34 year old male patient presented with slight sensitivity and mobility in several teeth. Despite the manufacturer's recommendations, the patient used a 22% carbamide peroxide‐based tooth bleaching gel at home for 4 days consecutively, at night, on the upper and lower arches. Clinical examination revealed gingival swelling, probing depths ranging 5–7 mm on the buccal and proximal surfaces, and grade 2 mobility of the teeth affected by ECRR. Radiographs revealed presence of ECRR in several teeth during initial examination, and development of multiple new lesions 6 months later. The teeth were subsequently extracted. Histological analysis showed multiple dentine lacunae and areas of dentine reparation. The careful use of these products can prevent sequelae such as those reported in this clinical case. As the vital bleaching has a variable success rate, patients should be informed through a consent form of the benefits and risks of tooth bleaching treatment. 相似文献
109.
Many children with acute lymphoblastic leukemia (ALL) develop a marrow relapse during or shortly following initial continuation chemotherapy. Achievement of a second complete remission is the initial step in a successful retreatment effort. Reinduction results using two or three drugs have been unsatisfactory, and previous reports of four-drug reinduction programs have included relatively small numbers of patients. Pediatric Oncology Group protocol 8303 was designed for patients with ALL in first marrow relapse during or within 6 months after cessation of chemotherapy. The results of reinduction therapy in 297 study patients are described here. Four-drug reinduction therapy consisted of daily oral prednisone, weekly vincristine and daunorubicin, and asparaginase three times weekly for 4 weeks (PVDA). CNS retreatment consisted of two doses of triple intrathecal chemotherapy. Of the 297 patients receiving reinduction, 245, or 82%, entered second complete remission, six died of infection or progressive disease, and 46 others still had M2 or M3 bone marrow status. Forty of these latter patients received four doses (during a 2-week period) of teniposide and cytarabine, after which 13 (32%) achieved complete remission status. Thus, the overall second complete remission rate with PVDA with or without teniposide/cytarabine was 258 of 297, or 87%. The treatment program was generally well tolerated. Among the numerous factors analyzed by using logistic regression, only female sex (P = .035), the presence of blasts on the blood smear at the time of relapse (P = .0002), and a length of initial complete remission less than 12 months (P = .021) were independent predictors of failure to enter second remission. We conclude that the intensive reinduction program described here is a highly effective first step in the delivery of salvage therapy to patients with ALL in first marrow relapse. The current challenge is to develop improved continuation treatment for these children. 相似文献
110.
Kitchingman GR; Mirro J; Stass S; Rovigatti U; Melvin SL; Williams DL; Raimondi SC; Murphy SB 《Blood》1986,67(3):698-703
We examined the arrangement of the mu heavy-chain immunoglobulin (Ig) genes in the leukemic blast cell DNA of 93 children with acute lymphoblastic leukemia (ALL). All cases met morphologic and cytochemical criteria for ALL, lacked detectable T cell surface antigens, and expressed HLA-DR (Ia) antigens. Eighty-three of the 93 patients (89%) were positive for the common acute lymphoblastic leukemia antigen (CALLA), and 20 of 91 (22%) tested had detectable cytoplasmic immunoglobulin. As expected, the heavy-chain lg gene was rearranged in all cases, and the pattern of rearrangements was variable; 23 had one allele rearranged and one in the germ line configuration; 15 had one rearranged and one deleted; and 37 had two rearranged. Unexpectedly, in 18 patients the presence of more than two mu gene-hybridizing bands was detected. Combinations of enzymes and heavy-chain gene probes were used to confirm that the extra bands were not the result of underdigestion of the DNA or DNA restriction site polymorphism. In eight of the 18 patients, we identified an extra chromosome 14 as a possible cause of the extra bands' hybridizing to the mu heavy-chain constant-region probe. In the remaining ten patients, the presence of three or four bands hybridizing with the mu probe suggests the presence of two populations of leukemic cells that may have arisen either by separate leukemic transformation events or by clonal evolution of one clone into two related lines. Although preliminary (2-year follow-up), our data suggest that childhood ALL of B lineage with more than two mu heavy-chain genes, but without extra copies of chromosome 14, may be more resistant to therapy. 相似文献