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p16INK4A and p15INK4B gene deletions in primary leukemias   总被引:4,自引:0,他引:4  
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   
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Human immunodeficiency virus‐related oral lesions (HIV‐OLs), such as oral candidiasis (OC) and oral hairy leukoplakia (OHL), have been recognized as indicators of immune suppression since the beginning of the global HIV epidemic. The diagnosis and management of HIV disease and spectrum of opportunistic infection has changed over the past 30 years as our understanding of the infection has evolved. We investigated the following controversial topics: (i) Are oral manifestations of HIV still relevant after the introduction of highly active antiretroviral therapy (HAART)? (ii) Can we nowadays still diagnose HIV infection through oral lesions? (iii) Is the actual classification of oral manifestations of HIV adequate or does it need to be reviewed and updated? (iv) Is there any novelty in the treatment of oral manifestations of HIV infection? Results from extensive literature review suggested the following: (i) While HAART has resulted in significant reductions in HIV‐OLs, many are still seen in patients with HIV infection, with OC remaining the most common lesion. While the relationship between oral warts and the immune reconstitution inflammatory syndrome is less clear, the malignant potential of oral human papillomavirus infection is gaining increasing attention. (ii) Effective antiretroviral therapy has transformed HIV from a fatal illness to a chronic manageable condition and as a result expanded screening policies for HIV are being advocated both in developed and in developing countries. Affordable, reliable, and easy‐to‐use diagnostic techniques have been recently introduced likely restricting the importance of HIV‐OLs in diagnosis. (iii) The 1993 EC‐Clearinghouse classification of HIV‐OLs is still globally used despite controversy on the relevance of periodontal diseases today. HIV‐OL case definitions were updated in 2009 to facilitate the accuracy of HIV‐OL diagnoses by non‐dental healthcare workers in large‐scale epidemiologic studies and clinical trials. (iv) Research over the last 6 years on novel modalities for the treatment of HIV‐OLs has been reported for OC and OHL.  相似文献   
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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   
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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   
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