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111.
Michael Crump Dongsheng Tu Lois Shepherd Mark Levine Vivien Bramwell Kathleen Pritchard 《Journal of clinical oncology》2003,21(16):3066-3071
PURPOSE: Cyclophosphamide, epirubicin, and fluorouracil (CEF), compared with classical cyclophosphamide, methotrexate, and fluorouracil (CMF) chemotherapy. has lead to an improvement in relapse-free and overall survival in premenopausal women with node-positive breast cancer. We undertook this analysis to more accurately define the estimate of risk of secondary acute leukemia (sAL) following epirubicin-containing chemotherapy regimens. PATIENTS AND METHODS: We assessed the conditional probability of sAL among 1,545 women who received adjuvant (n = 1,477) or neoadjuvant (n = 68) chemotherapy in four National Cancer Institute of Canada Clinical Trials Group trials from 1990 to 1999. The risks associated with epirubicin-containing regimens (CEF or epirubicin and cyclophosphamide [EC]) and other regimens (doxorubicin and cyclophosphamide [AC] or CMF) were determined. RESULTS: A total of 10 cases of sAL were observed (eight acute myelogeneous leukemia, two acute lymphoblastic leukemia): seven among women treated with CEF, two who had received AC, and one following CMF. Using competing risk statistics, the conditional probability of sAL was 1.7% (95% confidence interval [CI], 0.5 to 3.6) among 539 women treated with CEF chemotherapy at a follow-up of 8 years, 0.4% (95% CI, 0% to 1.3%) among the 678 who received CMF, and 1.3% (95% CI, 0% to 4.7%) among the 231 treated with AC. The conditional probability of death from breast cancer at 8 years for the entire group of women treated with epirubicin-containing regimens in all four trials was approximately 34.9%. CONCLUSION: CEF chemotherapy for breast cancer carries a small increased risk of sAL compared with CMF. These estimates of acute leukemia risk are important in discussing treatment with women, especially patients with a lower risk of death from breast cancer, such as those with node-negative breast cancer. 相似文献
112.
BACKGROUND: Tolerance to cardiac allografts can be induced in mice and rats by the injection of donor alloantigen into the thymus in combination with a CD4 T-cell-depleting antibody. CD8(+) cells in these animals are hyporesponsive to graft-specific alloantigens. Most of the CD8(+) T cells in the transgenic 2C mouse express a T-cell receptor specific for the class I major histocompatibility complex L(d+) locus. This study was designed to determine whether the adoptive transfer of these 2C T cells could precipitate rejection of a tolerant, completely major histocompatibility complex-mismatched L(d+) or L(d-) heart. METHODS: C57BL/6 mice (L(d-)) were given 10 x 10(6) cells of BALB/c (L(d+)) or dm2 (BALB/c background lacking L(d) [L(d-)]) splenocytes intrathymically and GK1. 5 (10 mg/kg) intraperitoneally. Twenty-one days later, BALB/c or dm2 hearts were transplanted. On the day of transplantation or after long-term allograft acceptance, recipients received naive 2C cells or 2C cells sensitized by in vitro mixed lymphocyte culture with BALB/c (L(d+)). RESULTS: Mean survival time of BALB/c cardiac allografts in untreated C57BL/6 mice was 7.3 days, although 73% of the mice that were pretreated with BALB/c splenocytes IT plus GK1.5 accepted the donor antigen-specific heart allografts indefinitely. All recipients that were pretreated with the intrathymic plus GK1.5 and that were injected with naive 2C cells at the time of heart transplantation experienced rejection of the BALB/c (L(d+)), but not the dm2 (L(d-)) hearts. In contrast, naive 2C cells could not reject tolerant (>30 days acceptance) BALB/c (L(d+)) hearts. 2C cells sensitized in vitro against L(d) were able to reject established BALB/c hearts but could not reject the L(d-) dm2 hearts. CONCLUSIONS: L(d)-specific 2C T-cell receptor transgenic T cells that are adoptively transferred to recipients will precipitate the rejection of accepted hearts that express class I L(d+) in mice rendered tolerant by an intrathymic injection of alloantigen plus anti-CD4 monoclonal antibodies. 相似文献
113.
人乙型肝炎病毒x基因转基因小鼠模型的建立 总被引:16,自引:0,他引:16
目的 建立人乙型肝炎病毒x(HBx)基因转基因小鼠模型。方法 用显微注射法制备转基因小鼠,用分子杂交法鉴定转基因小鼠HBx的整合与表达。结果 建立了人HBx的基因转基因小鼠模型。经Southern杂交鉴定得到17只转基因首建鼠。逢肝脏提取总RNA进行Northern杂交,结果显示17只首建鼠肝脏中均有HBx表达。结论 为从整体水平研究慢性乙肝炎患者诱发肝癌的作用机制及HBx的反式激活作用机制提供了 相似文献
114.
胸骨后甲状腺肿物的手术处理 总被引:1,自引:0,他引:1
为探讨胸骨后甲状腺肿物手术切除的进路方式,回顾性分析30年来外科治疗的结果。1965年至1994年间全部患者共87例,其中结节性甲状腺肿64例,占73.6%;甲状腺腺瘤13例,占14.9%;甲状腺恶性肿瘤10例,占11.5%。通过颈部入路手术切除的占70%(61/87),胸骨正中劈开切除的占16%(14/87),前切口开胸切除的占14%(12/87)。随着经验的积累,除误诊为纵隔其它来源的肿物外,1980年以后已不再行前切口开胸手术切除,1985年以后的43例中,只有1例胸骨后结节性甲状腺肿的患者行胸骨劈开手术,其余均从颈部入路手术。由于颈部入路相对并发症少、损伤小、安全可靠,建议对良性的胸骨后甲状腺肿物和部分恶性肿物行颈部衣领式切口手术。 相似文献
115.
116.
WG Mitchell H Lynn JF Bale MA Maeder SM Donfield B Garg AH Tilton JK Willis TP Bohan 《Pediatrics》1997,100(5):817-824
BACKGROUND: Boys and young men with hemophilia treated with factor infusions before 1985 had a substantial risk of acquiring the human immunodeficiency virus (HIV) and the acquired immunodeficiency syndrome. This study was designed to assess the effects of HIV and hemophilia per se on neurological function in a large cohort of subjects with hemophilia, and to investigate the relationships between neurological disease and death during follow-up. METHODS: Three hundred thirty-three boys and young men (207 HIV seropositive and 126 HIV seronegative) were evaluated longitudinally in a multicenter, multidisciplinary study. Neurological history and examination were conducted at baseline and annually for 4 years. The relationship between neurological variables, HIV serostatus, CD4+ cell counts, and vital status at the conclusion of the study was examined using logistic regression models. RESULTS: The risks of nonhemophilia-associated muscle atrophy, behavior change, and gait disturbance increased with time in immune compromised HIV-seropositive subjects compared with HIV seronegative or immunologically stable HIV-seropositive subjects. The risk of behavior change in immune compromised HIV-seropositive hemophiliacs, for example, rose to 60% by year 4 versus 10% to 17% for the other study groups. Forty-five subjects (13.5%), all of whom were HIV seropositive, died by year 4. Subjects who died had had increased risks of hyperreflexia, nonhemophilia-associated muscle atrophy, and behavior change. CONCLUSIONS: These results indicate that immune compromised, HIV-seropositive hemophiliacs have high rates of neurological abnormalities over time and that neurological abnormalities were common among subjects who later died. By contrast, immunologically stable HIV-seropositive subjects did not differ from the HIV-seronegative participants. Hemophilia per se was associated with progressive abnormalities of gait, coordination, and motor function. 相似文献
117.
Dermoid tumours in children usually occur in two locations: at the anterior fontanelle and on the occipital squama. An exceptional site of origin for a posterior fossa dermoid cyst is the extradural space. There are only six previous cases of this situation reported in the literature. A series of 103 subscalp and calvarial masses in children were reviewed and three children are reported with extradural dermoids of the posterior fossa, which communicated with the skin through midline occipital dermal sinuses. All three children were seen after the rapid growth or the formation of an abscess in a previously noted occipital subcutaneous mass present since birth. Although computed tomography or magnetic resonance imaging showed the dermal sinus and the intracranial tumour, these studies were unable to ascertain the intradural or extradural nature of the tumours, their exact origin only being established at operation. Histopathological study showed preclinical signs of infection in the two patients that had not yet formed an abscess. It is suggested that early neurosurgical treatment of these neoplasms should be done to prevent the development of severe intracranial infection. The previously reported simplicity of surgical removal of occipital extradural dermoids was not confirmed in this series. 相似文献
118.
农村城市化工业化进程中住院患者病种分析 总被引:1,自引:1,他引:1
目的研究农村城市化工业化过程中县级医院住院病种的变化规律.方法回顾性总结深圳市龙岗中心医院1998-2002年间的病案资料.结果前5类疾病为损伤中毒29.2%、妊娠分娩和产褥期并发症23.3%、呼吸系统疾病10.6%、消化系统疾病10.1%和循环系统疾病5.0%,合计占78.2%.前5种疾病为骨折、开放性创伤和血管损伤、肺炎、颅内和体内损伤及正常分娩,占33.9%.4年病人增加83.3%.结论在城市化工业化进程的早期和中期,县医院的病种更加集中,疾病构成比更加远离城市医院,其中损伤中毒、妊娠分娩产褥期并发症和起源于围产期的若干情况的人数明显增多,其它病种人数均减少.在此期间,医院治疗的重点是损伤、妊产病、呼吸和消化系统疾病. 相似文献
119.
The effects of bath applications of the nitric oxide (NO) donors sodium nitroprusside (SNP), diethylamine sodium (DEA), 3-morpholinosydnonimine (SIN-1), and S-nitroso-N-acetyl-penicillamine (SNAP) on the resting activity (RA) of afferent crista fibers were studied in isolated statocysts of the cuttlefish Sepia officinalis. The NO donors had three different effects: inhibition, excitation, and excitation followed by an inhibition. The SNAP analog N-acetyl-DL-penicillamine (xSNAP; with no NO moiety) had no effect. When the preparation was pre-treated with the NO synthase inhibitor N(G)-nitric-L-arginine methyl ester HCl (L-NAME), the NO donors were still effective. When the preparation was pre-treated with the guanylate cyclase inhibitors methylene blue (M-BLU) or cystamine (CYS), NO donors had only excitatory effects, whereas their effects were inhibitory only when pre-treatment was with the adenylate cyclase inhibitors nicotinic acid (NIC-A), 2',3'-dideoxyadenosine (DDA), or MDL-12330A. When pre-treatment was with a guanylate and an adenylate cyclase inhibitor combined, NO donors had no effect; in that situation, the RA of the afferent fibers remained and the preparation still responded to bath applications of GABA. Selective experiments with statocysts from the squid Sepioteuthis lessoniana and the octopod Octopus vulgaris gave comparable results. These data indicate that in cephalopod statocysts an inhibitory NO-cGMP and an excitatory NO-cAMP signal transduction pathway exist, that these two pathways are the key pathways for the action of NO, and that they have only modulatory effects on, and are not essential for the generation of, the RA. 相似文献
120.
Receptor activator of nuclear factor-kappaBligand(RANKL)promotes osteoclast formation,fusion,differentiation and activation.It plays akey role in osteoclast mediated bone erosion inrheumatoid arthritis(RA).Osteoprotegerin(OPG),as a soluble decoy receptor of RANKL,can prevent bone erosion in RA.Our previousstudies have shownthat Triptolide(TP),an activecompoundidentifiedin a traditional Chinese herb--Tripterygium wilfordii Hook F(TWHF),can ef-fectively inhibit bone destruction in ex… 相似文献