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31.
Chromodomain, helicase, DNA binding 5 (CHD5) is a member of a subclass of the chromatin remodeling Swi/Snf proteins and has recently been proposed as a tumor suppressor in a diverse range of human cancers. We analyzed all 41 coding exons of CHD5 for somatic mutations in 123 primary ovarian cancers as well as 60 primary breast cancers using high-resolution melt analysis. We also examined methylation of the CHD5 promoter in 48 ovarian cancer samples by methylation-specific single-stranded conformation polymorphism and bisulfite sequencing. In contrast to previous studies, no mutations were identified in the breast cancers, but somatic heterozygous missense mutations were identified in 3 of 123 ovarian cancers. We identified promoter methylation in 3 of 45 samples with normal CHD5 and in 2 of 3 samples with CHD5 mutation, suggesting these tumors may have biallelic inactivation of CHD5. Hemizygous copy number loss at CHD5 occurred in 6 of 85 samples as assessed by single nucleotide polymorphism array. Tumors with CHD5 mutation or methylation were more likely to have mutation of KRAS or BRAF (P = .04). The aggregate frequency of CHD5 haploinsufficiency or inactivation is 16.2% in ovarian cancer. Thus, CHD5 may play a role as a tumor suppressor gene in ovarian cancer; however, it is likely that there is another target of the frequent copy number neutral loss of heterozygosity observed at 1p36.  相似文献   
32.
Persistent perfluorinated organic compounds, such as perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) are used in a variety of industrial applications. They are very stable in the environment, distribute widely in the global environment and in wild life, and are detected in human sera.  相似文献   
33.
Two new sulfated steroidal pentaglycosides(asterosaponins),novaeguinosides Ⅰ(2) and (Ⅱ)2,along with the known regularoside B(1)were isolated from the starfish Culcita novaeguineae.Their structures were elucidated by extensive NMR techniques as well as chemical evidence.  相似文献   
34.
古宏标  汤聿海  徐毅 《药学学报》1996,31(10):732-736
以培养血管平滑肌细胞(vascularsmcothmusclecell,VSMC)为模型,观察了间硝苯地平(m-nifedipine,m-Nif)对血管紧张素Ⅱ(angiotensinⅡ,ANGⅡ)促进VSMC增殖和蛋白质合成的影响。结果表明,m-Nif抑制ANGⅡ(100nmol·L-1)引起VSMC[3H]thymidine和[3H]leucine参入,并呈剂量依赖性。m-Nif(2×10-6mol·L-1)可抑制ANGⅡ对VSMC的刺激、DNA及蛋白质合成速率,分别降低了46%,58%,53%。提示m-Nif可抑制ANGⅡ对VSMC增殖和蛋白合成的促进作用。  相似文献   
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Editor—We were surprised at the conclusion reached byMoore and colleagues1 in their evaluation of sevoflurane forpaediatric day-case anaesthesia, as the study data do not supportit. The reported adverse events during induction were no morethan would be expected during a typical gas induction. In addition,the significance of agitation and distress in the recovery areais difficult to gauge without details of an appropriate scoringsystem to include concomitant pain. Furthermore, though a statisticalsignificance  相似文献   
37.
The incidence of disseminated infection with Scedosporium species is increasing in patients with haematological malignancy. Two fatal cases are reported of patients with acute myeloid leukaemia and neutropenia who presented with Scedosporium endophthalmitis. Diagnosis of fungal infection was delayed as blood and vitreous cultures were positive only after 3 days in patient 1 and blood culture was positive at 7 days in patient 2. Despite antifungal therapy with amphotericin B and additional fluconazole in patient 2, both patients died of overwhelming fungal septicaemia. Post‐mortem examination of the right globe in patient 1 showed haemorrhagic necrotizing chorioretinitis with numerous fungal hyphae in choroidal vessels, choroid, retina and vitreous. Scedosporium species are often resistant to conventional antifungal therapy including amphotericin B. Diagnosis is difficult and mortality in disseminated infection is high.  相似文献   
38.
Background  The larvae of Lucilia sericata induce myiasis and transmit mycobacterial infections to humans and animals. Consequently, the blowfly should be controlled for human welfare and economic reasons.
Methods  The insecticidal effect of fenugreek ( Trigonella foenum-graecum ), celery ( Apium graveolens ), radish ( Raphanus sativus ), and mustard ( Brassica compestris ) against the third larval instars of L. sericata was evaluated, for the first time, through ingestion assays. The effect of sublethal concentrations on certain biological aspects, such as the pupation rates and adult emergence, was revealed.
Results  The LC50 values were 2.81, 4.60, 6.93, and 7.92% for fenugreek, celery, radish, and mustard, respectively. The adverse effects on larval treatment also included the survival of pupae and adults. The pupation rate was strongly decreased after treatment with 16% fenugreek and celery. Moreover, adult emergence was suppressed after treatment of larvae with 8% mustard, 12% radish, and 16% fenugreek and celery oils. The number of emerged males exceeded the number of females, which could lead to population decline. Morphologic abnormalities of larvae, pupae, and adults were recorded after treatment with all tested oils.
Conclusion  The results suggest that oils may represent new and safe potential insecticides for the control of blowflies.  相似文献   
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40.

Background  

Knowledge of the distribution of human papillomavirus (HPV) genotypes among women with cervical lesion and in invasive cervical cancer is crucial to guide the introduction of prophylactic vaccines. There is no published data concerning HPV and cervical abnormalities in Sudan. This study aimed to define the prevalence of HPV and its subtypes in the cervical smears of women presenting with gynecological complains at Omdurman Military Hospital, Sudan.  相似文献   
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