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排序方式: 共有654条查询结果,搜索用时 15 毫秒
21.
p16INK4A and p15INK4B gene deletions in primary leukemias 总被引:4,自引:0,他引:4
Haidar MA; Cao XB; Manshouri T; Chan LL; Glassman A; Kantarjian HM; Keating MJ; Beran MS; Albitar M 《Blood》1995,86(1):311-315
The 9p21 locus has been deleted at a high frequency in a wide variety of tumors. Recently, two genes, p16INK4A and p15INK4B (also called MTS1 and MTS2), have been localized in close proximity at the 9p21 locus, encoding cyclin-dependent kinases 4/6 inhibitors of relative molecular mass 16 kD and 15 kD, respectively and also found to be deleted at a high frequency in tumor cell lines. We analyzed p16INK4A and p15INK4B genes in 178 cases of primary leukemias including 81 cases of chronic lymphocytic leukemia (CLL), seven of hairy cell leukemia (HCL), seven of chronic myelogenous leukemia (CML), 43 of acute myelogenous leukemia (AML), 27 of acute lymphoblastic leukemia (ALL), and 13 of myelodysplastic syndrome (MDS) by Southern blot analyses. The ALL cases showed a relatively high frequency of homozygous deletions (22%, 6 of 27) at the p16INK4A gene locus. Interestingly, of the six cases with p16INK4A homozygous deletions, only three showed homozygous deletions at the p15INK4B gene. In 81 CLL patients, we detected one homozygous and five heterozygous deletions at both the p16INK4A and p15INK4B genes and two heterozygous deletions at the p16INK4A gene alone. Deletion of these two genes in AML cases is relatively low (9%). We did not detect deletions in any of the MDS, HCL, and CML cases examined. Sequence analyses of p16INK4A gene of six CLL cases with heterozygous deletion at this locus showed a 27-bp deletion at the splice acceptor site of intron 1 in one case and changes in the coding sequence in three other cases. The data presented in this report showed that (1) p16INK4A and p15INK4B genes are preferentially deleted homozygously in ALL and heterozygously in CLL cases with frequent mutation in the second allele, and (2) p16INK4A gene appears to be more frequently deleted than p15INK4B gene. 相似文献
22.
Dr. P.M. Lissel LL.M 《Notfall & Rettungsmedizin》2013,16(5):389-392
Background
Legal regulations concerning infection protection have been repeatedly revised in the last few years. At the national level the regulations for notifable diseases were recently broadened to include the suspicion of disease, the disease and death due to mumps, pertussis, rubella including congenital rubella and varicella (chickenpox). In addition notification deadlines were shortened in the new regulations and the information to be reported was expanded. At the “Bundesländer” level, there are also new regulations which expand notification concerning diseases and are extended to other contagious diseases. In addition, infection protection also includes measures to prevent and combat contagious diseases.Objective
This article describes the current legal situation. 相似文献23.
24.
25.
目的建立人血浆中醋酸环丙孕酮的HPLC—ESI—MS测定方法和丹酰氯衍生化血浆中炔雌醇的HPLC—APCI—MS测定方法,测定女性志愿者口服复方醋酸环丙孕酮片1片后的药代动力学参数,并对受试制剂和参比制剂的生物等效性进行评价。方法血浆样品中的炔雌醇以乙酸乙酯提取后,与丹酰氯发生衍生化反应,进行HPLC—APCI—MS分析,流动相为10mmol·L-1乙酸铵缓冲液(1%甲酸)-甲醇(3:97)。检测离子分别为m/z530.3(炔雌醇的丹酰氯衍生物)、m/z404.3(内标,对羟基联苯的丹酰氯衍生物1。结果在10.43~625.8Pg·ml-1范同内炔雌醇的丹酰氯衍生物与内标的丹酰氯衍生物峰面积比值与浓度呈良好的线性关系,最低定量限为10.43pg·ml-1结论本实验建立的分析方法灵敏、准确、简便,且统计学结果表明两种制剂生物等效。 相似文献
26.
Platelet-melanoma cell interaction is mediated by the glycoprotein IIb- IIIa complex 总被引:3,自引:0,他引:3
A human malignant melanoma cell line (M3Dau) was observed by electron microscopy to interact directly with human platelets and induced platelet aggregation. Fab fragments of a monoclonal antibody MoAb (LYP18), directed against the platelet glycoprotein (GP) IIb-IIIa complex, inhibited platelet-melanoma interactions and platelet-platelet aggregation. M3Dau melanoma cells bind LYP 18 and synthesize IIb-IIIa- like GPs. When the melanoma cells were preincubated with LYP 18, tumor- platelet interaction did not occur, suggesting that the interaction may be mediated by the IIb-IIIa-like GPs present on the melanoma cell surface. Glanzmann's thrombasthenic platelets, lacking GPIIb and IIIa, did not interact with melanoma cells, indicating that the platelet GPIIb-IIIa complex is also necessary for the platelet-melanoma cell interaction. This work demonstrates the importance of the IIb-IIIa-like GPs, present on M3Dau melanoma cells, in mediating tumor-platelet interactions. 相似文献
27.
LL Patton 《Oral diseases》2014,20(3):223-225
Over the last 30 years, there have been significant advances in our scientific knowledge of HIV disease, including prevention, detection, medical management, and attempts at cure. Investigations and observations of the oral cavity in individuals with HIV disease have contributed substantially to scientific discovery and innovation. Challenges remain for managing existing and emerging oral diseases associated with HIV and understanding the contribution of latent oral mucosal reservoirs to HIV eradication. 相似文献
28.
Effect of transforming growth factor-beta 1 on proliferation and induction of hemoglobin accumulation in K-562 cells 总被引:1,自引:1,他引:1
The effects of transforming growth factor-beta 1 (TGF-beta 1) on proliferation and hemoglobinization in K-562 cells, a human multipotential hematopoietic cell line, were studied. We found that TGF- beta 1 could induce hemoglobin accumulation in K-562 cells. Various clones were selected on the basis of the inducibility of hemoglobinization by TGF-beta 1. One high response clone (no. 1) and one low response clone (no. 8) were studied in detail. Hemoglobin accumulation peaked on day 5 of culture in the presence of TGF-beta 1 (0.5 ng/mL, 20 pmol/L), when 90% of clone 1 cells, 55% of parent line cells, and less than 10% of clone 8 cells contained hemoglobin. There was a concomitant reduction in proliferation of 60% for clone 1, 40% for the parent line, and 30% for the clone 8 on day 5 of culture. Quantitative analysis showed that the hemoglobin contents in clone 1 after 5-day induction by TGF-beta 1 and hemin were 1.0 pg/cell and 2.9 pg/cell, respectively. The hemoglobin induced by TGF-beta 1 showed the same electrophoretic characteristics as the hemoglobin induced by hemin. The expression of epsilon-globin mRNA was minimally detectable in control cells and was induced in both TGF-beta 1 and hemin treated cells. Other cytokines with potential effects on K-562 cell proliferation and differentiation were also studied. Interleukin-1, interleukin-3, interferon alpha, interferon gamma, and inhibin, tested as single agents, showed minimal effects on proliferation. None of these agents could induce hemoglobinization or inhibit the hemoglobinization induced by TGF-beta 1. 相似文献
29.
脑胶质瘤是颅内最常见的肿瘤。近年来关于神经胶质瘤的生物学研究取得了一定进展。首先是脑肿瘤干细胞的发现,其次是开展了肿瘤全基因组测序,这对于发现新的分子标记物是非常有用的,这些标记物(如IDH1基因突变)的发现甚至导致了基于分化和间质转化状况对神经胶质瘤的重新分类。此外,利用1p/19q标记及O6-甲基鸟嘌呤-DNA甲基转移酶基因(MGMT)是否被甲基化能为胶质瘤患者选择疗法和进行个性化药物治疗提供有意义的指导。作为治疗策略,替莫唑胺几年前已被确定为治疗脑胶质瘤的标准药物。最近在临床上贝伐单抗已开始用于脑胶质瘤的治疗。其他一些疗法目前还处于临床前开发和临床试验阶段,比如癌症疫苗、溶瘤腺病毒的研究等,这些潜在的疗法将来有可能成为胶质瘤治疗的手段或辅助手段。这些研究不仅揭示了神经胶质瘤的细胞起源,也为胶质瘤的诊断、治疗和预后判断提供了有用的信息和参考。 相似文献
30.
Queenan JT Jr; Veeck LL; Toner JP; Oehninger S; Muasher SJ 《Human reproduction (Oxford, England)》1997,12(7):1573-1576
In-vitro fertilization patients (n = 15) at risk of ovarian
hyperstimulation syndrome (OHSS) (oestradiol > or =4500 pg/ml on the day
of human chorionic gonadotrophin administration and 25 or more follicles of
intermediate or large size) underwent aspiration of all follicles and
cryopreservation of all fertilized oocytes at the pronuclear stage.
Patients were monitored for up to 2 weeks post- retrieval. Subsequent
transfer of cryopreserved-thawed embryos was performed in programmed cycles
using exogenous oestrogen and progesterone for endometrial preparation. Two
patients (13%) developed OHSS necessitating hospitalization and vaginal
aspiration of ascitic fluid. Two other patients (13%) developed moderate
OHSS requiring ascitic fluid vaginal aspiration in the office setting, with
dramatic improvement of the condition. Subsequent transfer of
cryopreserved- thawed embryos yielded a clinical pregnancy rate of 58% per
transfer and ongoing or delivery rates of 42 and 67% per transfer and per
patient respectively. By eliminating pregnancy potential with
cryopreservation of all prezygotes and examining the pregnancy potential
with subsequent cryopreserved-thawed transfers, it is concluded that OHSS
is reduced, but not eliminated for patients at risk. Subsequent transfer of
cryopreserved-thawed prezygotes in a programmed cycle with exogenous
steroids yields an excellent pregnancy rate.
相似文献