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31.
目的研究白血病抑制因子(LIF)在胚胎发育中的作用并探讨其参与胚泡着床的机制。方法收集昆明种小鼠的单细胞受精卵,连续培养120h,观察不同浓度LIF对胚胎发育的影响;用免疫印迹法测定培养液中细胞间粘附分子(ICAM-1的表达水平。结果LIF在0.1~10ng/ml浓度之间对胚胎发育有促进作用,其作用在桑椹胚及胚泡期最明显(P<0.05);LIF增加胚胎ICAM-1的表达,其作用在0.1ng/ml浓度时最强,并随着浓度的增加而减弱。结论适应浓度的LIF可促进胚胎发育,增加ICAM-1的表达,从而参与胚胎着床过程。 相似文献
32.
M. Caruso-Nicoletti M. Mancuso G. Spadaro S. P. Dibenedetto A. DiCataldo G. Schiliró 《European journal of pediatrics》1993,152(9):730-733
Growth impairment and growth hormone (GH) deficiency have been reported in children treated for acute lymphoblastic leukaemia (ALL). We have studied growth and GH secretion in a group of 50 patients, affected by ALL, during a 2- to 5-year period after diagnosis, and in 12 long-term-survivors. We observed a significant decrease in growth velocity during the 1st year (in particular during the first 6 months) of therapy and a catch-up growth after the end of therapy. Longterm survivors did not exhibit a significant reduction of height standard deviation score (SDS), as compared to height SDS at diagnosis. None of the patients showed GH deficiency. Our data indicate that chemotherapy significantly affects growth of patients treated for ALL, whereas radiotherapy-at the doses used in this study-does not induce GH deficiency, at least not within 9 years after diagnosis. 相似文献
33.
T. Buhr H. Choritz A. Georgii 《Virchows Archiv : an international journal of pathology》1992,420(6):473-478
Summary A histological study on sequential bone marrow biopsies in patients with chronic myeloid leukaemia (CML) was performed. We wished to answer the question as to whether a different content of megakaryopoiesis in the bone marrow of CML patients has a prognostic significance for the development of myelofibrosis during the course of disease. In addition, the significance of possible changes in the quantity of megakaryopoiesis in this process was assessed. In 186 patients who had no fibre increase at first diagnosis, the rate of subsequent myelofibrosis varied from 19% for the common or granulocytic subtype (CML.CT) to 40% for patients with features of megakaryocytic increase (CML.MI). No significant differences were found either in the rapidity of progression to fibrosis or in the final rate of osteomyelosclerosis. Whereas in CML.MI most patients (75%) showed an increase of fibres only, this was accompanied by an additional increase of megakaryocytes in CML.CT, changing the histological pattern from CML.CT to MI or MP, respectively. The data therefore revealed a correlation between fibre increase and subtyping of CML as suggested by the Hannover classification of chronic myeloproliferative diseases. Subtypes of CML with megakaryocytic increase could be shown to present a pre-myelofibrotic stage of disease and may therefore be conceived as a particular pathway of acceleration. 相似文献
34.
J. Diebold O. Riviere B. Gosselin A. Janin-Mercier A. Canelhas A. Le Tourneau J. Audouin 《Virchows Archiv : an international journal of pathology》1991,419(4):273-280
Summary Three cases of splenic involvement in three different types of generalized mastocytosis (systemic mast cell disease) are reported. The macroscopic, histological and ultrastructural modifications of the spleen are described. Each case exhibited a different morphological pattern. Giemsa staining, fluorescence after acridine orange staining and naphthol ASD chloracetate esterase reaction are shown to be valuable for diagnosis. By comparison, immunohistochemistry seemed not to be very useful, because no specific antigens are expressed. These findings are compared to previously published cases. Their value for the diagnosis and the prognosis are discussed. 相似文献
35.
多囊卵巢综合征患者卵泡液LIF、IL-1β及性激素水平与IVF-ET结局关系的研究 总被引:2,自引:2,他引:2
目的:探讨多囊卵巢综合征(PCOS)患者卵泡液中白血病抑制因子(LIF)、白细胞介素-1β(IL-1β)及性激素水平与IVF-ET结局的关系。方法:用酶联免疫双抗夹心法和时间分辨免疫荧光法前瞻性研究了行IVF-ET的11例PCOS患者、14例对照组患者卵泡液中IL-1β、LIF及雌二醇(E2)和孕酮(P)的定量表达。结果:PCOS组卵泡液中LIF为21.1±11.1pg/mL,P为191.9×103nmol/L,明显低于对照组(33.5±11.8pg/mL,305.9×103nmol/L,P<0.05);而PCOS组卵泡液IL-Iβ为39.9±11.5pg/mL,E2浓度为3334.00nmol/L,明显高于对照组(28.3±10.6pg/mL,2138.1nmol/L),P<0.05。PCOS组胚胎种植率为8.8%,临床妊娠率为18.2%,明显低于对照组(16.7%,42.9%),P<0.05;PCOS组OHSS发生率为27.3%,明显高于对照组(7.1%,P<0.05)。LIF与E2在两组患者呈负相关(r=-0.442,P=0.027)、LIF与LH/FSH比值在PCOS组呈负相关(r=-0.682,P=0.021);IL-Iβ与E2在PCOS组呈正相关(r=0.612,P=0.045);LH/FSH比值与P在PCOS组呈负相关(r=-0.780,P=0.005);LIF与IL-Iβ水平两者间无明显相关性。结论:LIF可能是PCOS患者低种植率的关键因子;IL-Iβ可能是PCOS患者在控制性超排卵过程中易发生OHSS的一个致病因子;卵泡液IL-Iβ、LIF受卵巢激素调控。 相似文献
36.
Benjamin W. Teh Constantine S. Tam Sasanka Handunnetti Leon J. Worth Monica A. Slavin 《Blood reviews》2018,32(6):499-507
Chronic lymphocytic leukaemia (CLL) is the most common leukaemia with infections a leading cause of morbidity and mortality. Recently there has been a paradigm shift from the use of chemo-immunotherapies to agents targeting specific B-lymphocyte pathways. These agents include ibrutinib, idelalisib and venetoclax. In this review, the risks and timing of infections associated with these agents are described, taking into account disease and treatment status. Treatment with ibrutinib as monotherapy or in combination with chemo-immunotherapies is not associated with additional risk for infection. In contrast, the use of idelalisib is associated with a 2-fold risk for severe infection and opportunistic infections. Venetoclax does not appear to be associated with additional infection risk. The evolving spectrum of pathogens responsible infections in CLL patients, especially those with relapsed and refractory disease are described, and prevention strategies (prophylaxis, monitoring and vaccination) are proposed. 相似文献
37.
38.
《Expert opinion on investigational drugs》2013,22(6):1197-1205
Although the standard approach to myeloid leukaemias remains chemotherapy, the agents currently available rarely result in cure. Recent advances in understanding the biology of these disorders have lead to the development of targeted treatment strategies. In acute promyelocytic leukaemia (APL), all-trans retinoic acid (ATRA), sodium phenylbutyrate and arsenic trioxide are agents which either induce differentiation or apoptosis and have been used to successfully achieve remission. The tyrosine kinase inhibitor, STI-571, antisense oligonucleotides, and bcr-abl vaccines are strategies which focus on the oncogenic events in chronic myelogenous leukaemia (CML). Two anti-CD33 monoclonal antibody conjugates, Y90-HuM195 and CMA-676, have been used in acute myelogenous leukaemia (AML) and have shown some efficacy. Although the preliminary results with these targeted therapies are promising, further studies are needed to establish them as effective, less toxic alternatives to the current standard of care. 相似文献
39.
《British journal of haematology》2017,179(4):530-542
Acute myeloid leukaemia (AML) is a biologically complex, molecularly and clinically heterogeneous disease. Despite major advances in understanding the genetic landscape of AML and its impact on the pathophysiology and biology of the disease, standard treatment options have not significantly changed during the past three decades. AML is characterized by multiple somatically acquired mutations that affect genes of different functional categories. Mutations in genes encoding epigenetic modifiers, such as DNMT3A, ASXL1, TET2, IDH1, and IDH2, are commonly acquired early and are present in the founding clone. By contrast, mutations involving NPM1 or signalling molecules (e.g., FLT3, RAS gene family) are typically secondary events that occur later during leukaemogenesis. This review aims to provide an overview of advances in new prognostic markers, including targetable mutations that will probably guide the development and use of novel molecularly targeted therapies. 相似文献
40.
《Expert opinion on therapeutic patents》2013,23(11):1773-1790
Introduction: Phosphatidylinositol 3-kinase (PI3K), a lipid kinase, is the first kinase involved in, and a key component of, the PI3K/Akt/mTOR signalling pathway, and is significantly upregulated in many cancers. However, four distinct isoforms of PI3K are known with different expression patterns and different pathophysiological roles. The PI3Kδ isoform is expressed in leukocytes and has been implicated as a potential target in the development of selective inhibitors for the treatment of haematological malignancies and various inflammatory diseases. Areas covered: This review briefly covers the understanding of the four PI3K isoforms and their roles and the inhibitors selective for either one or two isoforms that have been identified to date. It then focuses upon progress in the identification of selective PI3Kδ inhibitors focusing upon the original efforts at ICOS/Calistoga that led to the initial clinical candidates such as CAL-101. After assessing the patent filings from these companies, it considers filings from other players and how they have sought to explore similar, and structurally distinct, scaffolds in their search for selective inhibitors, and how different companies appear focused on either oncological or anti-inflammatory uses for their inhibitors. Expert opinion: The impact of the work at ICOS is highlighted by the fact that prior to their disclosure of selective leads, no patent applications claiming selective PI3Kδ inhibitors had been filed by other companies. This disclosure, followed by the first filings by Piramed, led to an upsurge in interest with a large cluster of filings published in 2008 while half the relevant applications were published in 2010 or 2011. These efforts, and the initial clinical data on CAL-101, the leading PI3Kδ inhibitors, have also prompted a number of commercially significant deals. In addition to an increasing number of filings, the entry into the clinical development of more selective PI3Kδ inhibitors should stimulate a better understanding of the role of this specific kinase isoform. 相似文献