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排序方式: 共有630条查询结果,搜索用时 15 毫秒
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Koppler H.; Pfluger K.-H.; Eschenbach I.; Pfab R.; Birkmann J.; Zeller W.; Holle R.; Steinhauer U. E.; Gropp C.; Oehl S.; Lennert K.; Parwaresch M. R.; Kuhn H.; Drings P.; Gossmann H. H.; Khoury M.; Schubotz R.; Havemann K. 《Annals of oncology》1994,5(1):49-55
Background: With CHOP, the standard protocol of recent decades,about 30% of long-term survival has been reported. A numberof studies using more aggressive multidrug regimens or alternatingchemotherapies have recently suggested higher CR rates and increasedsurvival. In 1989 we reported similar results with a combined-modalitytreatment administering 6 cycles of CHOP supplemented with etoposideand an involved field irradiation for patients in PR or CR. Patients and methods: To confirm the efficacy of this approach,we initiated a prospective randomised trial comparing 4 cyclesof CHOP-VP 16 (CHOEP) with 4 cycles of two alternating regimens,hCHOP and IVEP. One hundred seventy-five patientswith high-grade non-Hodgkin's lymphomas stages II-IV were stratifiedfor age, stage and LDH and randomised to receive either fourcycles of cyclophosphamide, doxorubicin, vincristine, etoposide,prednisolone (CHOEP) in arm A or four cycles of chemotherapywith a dose-intensified CHOP (hCHOP) alternating with ifosfamide,etoposide, vindesine, prednisolone (IVEP) in arm B. After fourcycles of chemotherapy an involved field irradiation with atotal dose of 35 Gy was given to all patients demonstrated tobe in complete or partial remission. Results: Of the 185 randomised patients, 175 were eligible and171 evaluable for response and survival. One hundred forty-sixof the 171 patients (85%) achieved complete remission (CR) with87% and 84% CRs in arms A and B, respectively. With a medianfollow-up of 36 months the estimated overall survival at 2 yearsis 66% and 73% for arms A and B. The percentage of all patientsin first CR is estimated to be 59% and 55% at 2 years for armsA and B, respectively. None of the differences in CR rate, survival,or relapse-free survival are statistically significant. Multivariateanalysis of subgroups incorporating the factors of sex, age,performance status, stage, B symptoms, bulky disease, LDH andhistology revealed that only stage and LDH were factors whichindependently affected outcome. The estimated 2-year survivalrate of patients with stages II, III and IV is predicted tobe 84%, 62% and 52%, respectively. Patients with LDH >250U/I have an estimated survival of 52% at 2 years versus 84%for patients with LDH 相似文献
5.
Perforated colorectal neoplasms: correlation of clinical, contrast enema, and CT examinations 总被引:2,自引:0,他引:2
Hulnick DH; Megibow AJ; Balthazar EJ; Gordon RB; Surapenini R; Bosniak MA 《Radiology》1987,164(3):611-615
Results of clinical, contrast enema (CE), and computed tomographic (CT) examinations in 39 patients with perforated colorectal neoplasms were retrospectively reviewed. Twenty patients were toxemic at initial presentation, but in only four patients was the diagnosis of perforated colorectal neoplasm initially suspected clinically. CE study was performed in 22 patients and enabled the diagnosis of perforated neoplasm in 11 cases, neoplasm alone in eight, and neither neoplasm nor perforation in three. CT was performed in 38 patients and enabled the diagnosis of perforated neoplasm in 36; pericolic phlegmon but no mass lesion was evident in two. In 16 patients, CT also demonstrated metastatic disease. Because of its reliability in establishing the diagnosis and staging the extent of the inflammatory and neoplastic disease, CT is indicated in cases of suspected or proved perforated colorectal neoplasm and in cases in which CE study findings are indeterminate or suggestive of perforated neoplasm. 相似文献
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Temperature distributions from 136 superficial radiothermotherapies in patients were analysed and three-dimensionally reconstructed. The calculation of mean values and standard deviations of the temperature measuring probes considering water bolus temperature, master probe temperature, site of the probes relatively to different applicator positions and site of the probes in the heated tissues yielded satisfactory temperature distributions for chest wall treatment in contrast to other regions of the body. Radiothermotherapy was statistically not superior to radiotherapy alone with respect to local tumor control. 相似文献
8.
Coralline hydroxyapatite bone graft substitutes: preliminary report of radiographic evaluation 总被引:1,自引:0,他引:1
A new bone graft substitute made by conversion of the calcium carbonate exoskeleton of reef-building sea coral into hydroxyapatite has recently become clinically available. The normal radiographic appearance of two forms of this material is described. In the immediate postoperative period, the exoskeletal architecture of these implants is readily appreciated. With graft incorporation over the ensuing months, their intrinsic structure is gradually lost in association with poor marginal definition. Evolving radiographic findings reflect the biocompatible nature of these implants, which provides the potential for ingrowth of native bone with preservation of the coralline scaffold, resulting in enhanced biomechanical properties. 相似文献
9.
Neurofibromatosis 2 (NF2) is an inherited cancer syndrome resulting from
mutations in the NF2 tumor suppressor gene. Analysis of NF2 mutations has
revealed some general genotype-phenotype correlations. Severe disease has
been associated with mutations that produce a premature termination while
more mild disease has been associated with missense mutations. Here, we
provide experimental proof for these genotype-phenotype correlations by
demonstrating that nonsense mutations fail to produce stable merlin protein
while missense mutations result in the generation of merlin proteins
defective in negative growth regulation. This inability to suppress cell
growth may result from defects in the function of merlin at several levels,
including failure to form an intramolecular complex. Based on these
findings, we propose a model for merlin growth suppression that provides a
framework for analyzing NF2 patient mutations and merlin function.
相似文献
10.
Induction of B cell apoptosis by co-cross-linking CD23 and sIg involves aberrant regulation of c-myc and is inhibited by bcl-2 总被引:2,自引:0,他引:2
Campbell KA; Studer EJ; Kilmon MA; Lees A; Finkelman F; Conrad DH 《International immunology》1997,9(8):1131-1140
A novel system to study the effects of co-cross-linking CD23/FceRII and sIg
on murine B lymphocytes utilizes a highly multivalent form of anti- Ig
prepared by covalently linking anti-Ig antibodies to a DNP-dextran
backbone. CD23-sIg co-cross-linking is accomplished by the addition of
DNP-specific monoclonal IgE. Previous studies demonstrated that co-
cross-linking CD23 and sIg significantly inhibited mouse B cell
proliferation, especially at high doses of the multivalent anti-Ig.
Interestingly, examination of early activation signals reveals no
difference in B cells subjected to co-cross-linking conditions as compared
to B cells activated with anti-Ig alone. Total cellular protein tyrosine
phosphorylation levels are unchanged by co-cross- linking. Analysis of B
cell mRNA reveals that co-cross-linking the receptors does not alter the
expression levels of ornithine decarboxylase 8 h after stimulation as
compared to the controls. In contrast, levels of the proto-oncogene c-myc
were significantly elevated 1 h after inducing B cell activation under
co-cross-linking conditions. However, it remains unclear whether this
aberrant c-myc regulation plays any role in inducing apoptosis. In
addition, on day 3 after stimulation, the co-cross-linking of CD23 and sIg
resulted in the formation of apoptotic B cells, determined by both
photomicroscopy of the B cell cultures and FACS analysis of B cell nuclei.
B cells obtained from bcl-2 transgenic mice proliferated as well as
controls, and failed to undergo apoptosis when CD23 and sIg were
co-cross-linked on their surface. These studies indicate that
co-cross-linking of CD23 with B cell sIg inhibits B cell proliferation by a
mechanism that is distinct from that seen by co-cross-linking of the Fc
gamma RII and sIg. In addition, these results suggest a means by which
antigen- specific IgE can down-regulate additional B cell activation and
IgE synthesis.
相似文献