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171.
Results of allogeneic bone marrow transplants for leukemia using donors other than HLA-identical siblings 总被引:1,自引:0,他引:1
R Szydlo JM Goldman JP Klein RP Gale RC Ash FH Bach BA Bradley JT Casper N Flomenberg JL Gajewski E Gluckman PJ Henslee-Downey JM Hows N Jacobsen HJ Kolb B Lowenberg T Masaoka PA Rowlings PM Sondel DW van Bekkum JJ van Rood MR Vowels MJ Zhang MM Horowitz 《Canadian Metallurgical Quarterly》1997,15(5):1767-1777
PURPOSE: To compare outcomes of bone marrow transplants for leukemia from HLA-identical siblings, haploidentical HLA-mismatched relatives, and HLA-matched and mismatched unrelated donors. PATIENTS: A total of 2,055 recipients of allogeneic bone marrow transplants for chronic myelogenous leukemia (CML), acute myelogenous leukemia (AML), and acute lymphoblastic leukemia (ALL) were entered onto the study. Transplants were performed between 1985 and 1991 and reported to the International Bone Marrow Transplant Registry (IBMTR). Donors were HLA-identical siblings (n = 1,224); haploidentical relatives mismatched for one (n = 238) or two (n = 102) HLA-A, -B, or -DR antigens; or unrelated persons who were HLA-matched (n = 383) or mismatched for one HLA-A, -B, or -DR antigen (n = 108). HLA typing was performed using serologic techniques. RESULTS: Transplant-related mortality was significantly higher after alternative donor transplants than after HLA-identical sibling transplants. Among patients with early leukemia (CML in chronic phase or acute leukemia in first remission), 3-year transplant-related mortality (+/-SE) was 21% +/- 2% after HLA-identical sibling transplants and greater than 50% after all types of alternative donor transplants studied. Among patients with early leukemia, relative risks of treatment failure (inverse of leukemia-free survival), using HLA-identical sibling transplants as the reference group, were 2.43 (P < .0001) with 1-HLA-antigen-mismatched related donors, 3.79 (P < .0001) with 2-HLA-antigen-mismatched related donors, 2.11 (P < .0001) with HLA-matched unrelated donors, and 3.33 (P < .0001) with 1-HLA-antigen-mismatched unrelated donors. For patients with more advanced leukemia, differences in treatment failure were less striking: 1-HLA-antigen-mismatched relatives, 1.22 (P = not significant [NS]); 2-HLA-antigen-mismatched relatives, 1.81 (P < .0001); HLA-matched unrelated donors, 1.39 (P = .002); and 1-HLA-antigen-mismatched unrelated donors, 1.63 (P = .002). CONCLUSION: Although transplants from alternative donors are effective in some patients with leukemia, treatment failure is higher than after HLA-identical sibling transplants. Outcome depends on leukemia state, donor-recipient relationship, and degree of HLA matching. In early leukemia, alternative donor transplants have a more than twofold increased risk of treatment failure compared with HLA-identical sibling transplants. This difference is less in advanced leukemia. 相似文献
172.
Preproenkephalin (PPE) gene expression is specifically induced by estrogen in hypothalamus of ovariectomized (OVX) females, better than in male rats. To study estrogen actions on gene regulation, we have presently characterized protein-DNA interactions by use of a consensus estrogen response element (ERE) and a putative ERE from PPE gene, with nuclear extracts from hypothalamus. By use of the electrophoretic mobility shift assay (EMSA), ERE binding activity was detected in nuclear extracts from neuronal tissues including hypothalamus, hippocampus, striatum, cerebellum and frontal cortex, and non-neuronal tissues such as pituitary and uterus, but not lung of OVX female rats with a consensus ERE, as well as a 129-bp PCR fragment from PPE promoter and a hairpin oligonucleotide that contains a putative ERE of the rat PPE gene. The ERE binding was eliminated by the addition of specific ERE-containing oligonucleotide, but not control oligonucleotides. Protein and DNA associated and dissociated very rapidly. By use of supershift assay, interactions of estrogen receptor with ERE were demonstrated in hypothalamic nuclear extracts. The initial levels of specific ERE binding in the hypothalamic nuclear extracts were comparable between castrated male and OVX female rats. However, estrogen treatment, either estradiol or estradiol benzoate, produced a rapid and tissue-specific induction of a slow mobility complex of ERE binding in hypothalamic nuclear extracts from females, better than in male rats, presumably from other associated factors, or a conformational change or other posttranslational modifications. This estrogen-induced slow mobility complex of ERE binding in hypothalamus was not observed after treatment with progesterone or tamoxifen. These results suggest that specific ERE binding is present in rat hypothalamic nuclear proteins, which may contribute to the upregulation of PPE gene expression by estrogen, and that the sexually differentiated action of estrogen may be related to an estrogen-induced conformational change, but not to the initial level of ERE-binding activity. 相似文献
173.
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175.
beta Pictoris is the best known example of a main-sequence star encircled by a tenuous disk. Optical and infrared images of beta Pic suggest that the disk is composed of dust grains which have been interpreted as the debris generated by the disruption of the asteroid-sized remnants of planet-formation processes. The star itself is relatively old, with an age in excess of 100 Myr. Here we present high-resolution millimetre-wave images of continuum and molecular-line emission from dust and gas surrounding a much younger star, MWC480: the stellar properties of MWC480 are similar to those of beta Pic, but its age is just 6Myr. The morphology of the circumstellar material and a comparison with the predictions of kinematic modelling indicate the presence of a rotating disk, gravitationally bound to the star. Moreover, the mass of the disk is greater than the minimum required to form a planetary system like our own. We therefore suggest that the disk around the young star MWC480 could be a progenitor of debris disks of the type associated with older stars such as beta Pic, and so holds much promise for the study of both the origin of debris disks and the early stages of the formation of planetary systems. 相似文献
176.
EW Hook WM McCormack D Martin RB Jones K Bean AN Maroli 《Canadian Metallurgical Quarterly》1997,41(8):1843-1845
In a randomized open study, 351 male patients with uncomplicated gonorrhea were given single oral doses of grepafloxacin (400 mg) or cefixime (400 mg). In the 299 microbiologically evaluable patients, urethral infections were cured in 99% (147 of 149) of those receiving grepafloxacin and 97% (145 of 150) of those given cefixime. Eradication rates for both regimens were 100% in the 16% (47 of 299) of participants who were infected with penicillin-resistant Neisseria gonorrhoeae and 97% in the 21% (62 of 299) of participants infected with tetracycline-resistant strains. Grepafloxacin is a well-tolerated alternative to cefixime for treatment of uncomplicated gonorrhea in males. 相似文献
177.
Recent work in many laboratories has revealed that cytokines are important mediators of inflammation, host defense, and tissue injury in a variety of neurological diseases. A role for astrocytes and microglia in these diseases has been considered pivotal, since both cell types readily produce and respond to cytokines in vitro and show morphologic and immunocytochemical evidence for activation in vivo. Although much of the work documenting these events has been generated in rodent systems, our laboratory has focused on human cell culture systems to define the nature of the activating signals for human microglia and astrocytes and their responses to activating cytokines and growth factors and evidence for activation. The results have shown that interleukin-1 (IL-1) is a potent activator of human astrocytes and induces cytokines such as tumor necrosis factor alpha and interleukin-6, and is a potent activator of nitric oxide generation in astrocytes. Astrocytes also promote microglial growth and differentiation through production of colony-stimulating factors, an activity that is enhanced following activation with IL-1. This review will summarize the human glia data generated in this and other laboratories and present hypotheses how glia may participate in certain human central nervous system diseases. 相似文献
178.
Laparoscopically assisted vaginal hysterectomy 总被引:1,自引:0,他引:1
OBJECTIVE: To report our experience with laparoscopically assisted vaginal hysterectomy (LAVH) and evaluate the advantages of LAVH. STUDY DESIGN: From January 1991 to August 1992, 176 LAVHs were performed at the Department of Obstetrics and Gynecology, College of Medicine, Chung-Ang University, Seoul, Korea. The indications for LAVH, based on the preoperative diagnosis, were uterine myomas, dysmenorrhea, chronic pelvic inflammatory disease or pelvic pain, dysfunctional uterine bleeding and cervical intraepithelial neoplasia (in order of frequency). RESULTS: Patients had concomitant procedures, including incidental appendectomy, posterior wall repair, pelvic adhesiolysis and salpingo-oophorectomy. Bipolar forceps were used to compress and desiccate vessels. The Nd-YAG laser, scissors and/or unipolar electrode were used for tissue division, excision of adhesions and cutting. The intraoperative complications were bladder perforation, massive hemorrhage and inferior epigastric vessel injury (one case each). The postoperative complications were infection, voiding difficulty, febrile morbidity, pelvic abscess, incisional hernia, vaginal vault bleeding and peroneal nerve palsy (one case each). CONCLUSION: Hysterectomy can be safely performed vaginally assisted by operative laparoscopy by well-trained laparoscopists, resulting in reduced surgical morbidity, blood loss, postoperative discomfort, recovery time and hospitalization. 相似文献
179.
MJ Koury DW Horne ZA Brown JA Pietenpol BC Blount BN Ames R Hard ST Koury 《Canadian Metallurgical Quarterly》1997,89(12):4617-4623
An in vitro model of folate-deficient erythropoiesis has been developed using proerythroblasts isolated from the spleens of Friend virus-infected mice fed an amino acid-based, folate-free diet. Control proerythroblasts were obtained from Friend virus-infected mice fed the same diet plus 2 mg folic acid/kg diet. Our previous studies showed that, after 20 to 32 hours of culture in folate-deficient medium with 4 U/mL of erythropoietin, the folate-deficient proerythroblasts underwent apoptosis, whereas control erythroblasts survived and differentiated into reticulocytes over a period of 48 hours. The addition of folic acid or thymidine to the folate-deficient medium prevented the apoptosis of the folate-deficient erythroblasts, thereby implicating decreased thymidylate synthesis as the main cause of apoptosis in the folate-deficient erythroblasts. In the study reported here, we examined intracellular folate levels, uracil misincorporation into DNA, p53 and p21 proteins, and reticulocyte formation in erythroblasts cultured in folate-deficient or control medium. In all experiments, the folate-deficient erythroblasts cultured in folate-deficient medium gave results that varied significantly from folate-deficient erythroblasts cultured in control medium or control erythroblasts cultured in either folate-deficient or control media. Folate-deficient erythroblasts cultured in folate-deficient medium had marked decreases in all coenzyme forms of folate that persisted throughout culture, increased uracil misincorporation into DNA, persistent accumulations of p53 and p21, and decreased reticulocyte production but increased size of individual reticulocytes. A model of folate-deficient erythropoiesis based on apoptosis of late stage erythroblasts is presented. This model provides explanations for the clinical findings in megaloblastic anemia. 相似文献
180.
Medical and neuropsychiatric sequelae of HIV infection present a spectrum of diagnostic and treatment challenges to mental health clinicians. Both HIV and the many opportunistic infections that manifest in patients due to their immunocompromised state also can affect the central nervous system (CNS). Thus, mental health clinicians need to be familiar with the diagnosis and management of HIV-related medical and psychiatric complications. This article provides an overview of the CNS-related manifestations resulting from HIV disease, including HIV-related dementia, psychotic disorders, delirium, CNS opportunistic infections and tumors, systemic abnormalities, psychoactive substances, and the adverse effects of certain medical treatments. Treatment strategies for individuals with HIV disease and comorbid severe mental illness are outlined and recommendations for future research are offered. 相似文献