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Cryogenic burns are uncommon. We present two patients who presented to a Regional Burns Unit on consecutive days with almost identical burn injuries caused by exposure to a unique source of sub-zero temperature, the spray from an aerosol deodorant. The clinical features and management of the cases are outlined, and we discuss the mechanism of a cryogenic burn. 相似文献
3.
Chan AO Broaddus RR Houlihan PS Issa JP Hamilton SR Rashid A 《The American journal of pathology》2002,160(5):1823-1830
Aberrant crypt foci (ACF) are postulated to be the earliest precursor lesion in colorectal carcinogenesis, and CpG island methylation has been described as an important molecular pathway. We therefore studied methylation in ACF from patients with familial adenomatous polyposis (FAP) or sporadic colorectal cancer. We assessed methylation status of the p16 tumor suppressor gene, MINT1 (methylated in tumor 1), MINT2, MINT31, O(6)-methylguanine-DNA methyltransferase gene, and hMLH1 mismatch repair gene. We compared methylation to ACF histopathology, K-ras proto-oncogene mutation, loss of heterozygosity at chromosome 1p, and microsatellite instability. Methylation was present in 34% (21 of 61) of ACF, including both FAP and sporadic types, but was more frequent in sporadic ACF [53% (18 of 34) versus 11% (3 of 27), P = 0.002], especially dysplastic sporadic ACF [75% (3 of 4) versus 8% (2 of 24), P = 0.004]. MINT31 was more frequently methylated in heteroplastic ACF than dysplastic ACF [35% (11 of 31) versus 7% (2 of 30), P = 0.01]. Strong associations of ACF methylation with K-ras mutation (P = 0.007) and with loss of chromosome 1p (P = 0.04) were observed, but methylation was the only molecular abnormality identified in 16% (10 of 61) of ACF. Our findings suggest that methylation in ACF is an early event in the pathogenesis of a subset of colorectal carcinomas, and that ACF from FAP patients and patients with sporadic colorectal cancer have distinct epigenetic changes that reflect differences in molecular pathogenesis. 相似文献
4.
Santos RL Wajid M Khan MN McArthur N Pham TL Bhatti A Lee K Irshad S Mir A Yan K Chahrour MH Ansar M Ahmad W Leal SM 《Human mutation》2005,26(4):396
Though many hearing impairment genes have been identified, only a few of these genes have been screened in population studies. For this study, 168 Pakistani families with autosomal recessive hearing impairment not due to mutations in the GJB2 (Cx26) gene underwent a genome scan. Two-point and multipoint parametric linkage analyses were carried out. Twelve families had two-point or multipoint LOD scores of 1.4 or greater within the transmembrane cochlear expressed gene 1 (TMC1) region and were subjected to further screening with direct DNA sequencing. Five novel putatively functional non-synonymous sequence variants, c.830A>G (p.Y277C), c.1114G>A (p.V372M), c.1334G>A (p.R445H), c.2004T>G (p.S668R), and c.2035G>A (p.E679K), were found to segregate within seven families, but were not observed in 234 Pakistani control chromosomes. The variants c.830A>G (p.Y277C), c.1114G>A (p.V372M), and c.1334G>A (p.R445H) occurred at highly conserved regions and were predicted to lie within hydrophobic transmembrane domains, while non-synonymous variants c.2004T>G (p.S668R) and c.2035G>A (p.E679K) occurred in extracellular regions that were not highly conserved. There is evidence that the c.2004T>G (p.S668R) variant may have occurred at a phosphorylation site. One family has the known splice site mutation c.536 -8T>A. The prevalence of non-syndromic hearing impairment due to TMC1 in this Pakistani population is 4.4% (95%CI: 1.9, 8.6%). The TMC1 protein might have an important function in K(+) channels of inner hair cells, which would be consistent with the hypothetical structure of protein domains in which sequence variants were identified. 相似文献
5.
Munaza Fatima Santosh Kumar Mudassar Hussain Naveed Masood Memon Anum Vighio Muhammad Asif Syed Ambreen Chaudhry Zakir Hussain Zeeshan Iqbal Baig Mirza Amir Baig Rana Jawad Asghar Aamer Ikram Yousef Khader 《JMIR Public Health and Surveillance》2021,7(5)
BackgroundHyderabad, Pakistan, was the first city to witness an outbreak of extensively drug resistant (XDR) typhoid fever. The outbreak strain is resistant to ampicillin, chloramphenicol, trimethoprim-sulfamethoxazole, fluoroquinolones, and third-generation cephalosporin, thus greatly limiting treatment options. However, despite over 5000 documented cases, information on mortality and morbidity has been limited.ObjectiveTo address the existing knowledge gap, this study aimed to assess the morbidity and mortality associated with XDR and non-XDR Salmonella serovar Typhi infections in Pakistan.MethodsWe reviewed the medical records of culture-confirmed typhoid cases in 5 hospitals in Hyderabad from October 1, 2016, to September 30, 2018. We recorded data on age, gender, onset of fever, physical examination, serological and microbiological test results, treatment before and during hospitalization, duration of hospitalization, complications, and deaths.ResultsA total of 1452 culture-confirmed typhoid cases, including 947 (66%) XDR typhoid cases and 505 (34%) non-XDR typhoid cases, were identified. Overall, ≥1 complications were reported in 360 (38%) patients with XDR typhoid and 89 (18%) patients with non-XDR typhoid (P<.001). Ileal perforation was the most commonly reported complication in both patients with XDR typhoid (n=210, 23%) and patients with non-XDR typhoid (n=71, 14%) (P<.001). Overall, mortality was documented among 17 (1.8%) patients with XDR S Typhi infections and 3 (0.6%) patients with non-XDR S Typhi infections (P=.06).ConclusionsAs this first XDR typhoid outbreak continues to spread, the increased duration of illness before hospitalization and increased rate of complications have important implications for clinical care and medical costs and heighten the importance of prevention and control measures. 相似文献
6.
Neoplasms of the soft tissues cause localized swelling and a variable degree of tissue response on the part of the host; these features they share with many non-neoplastic disorders. A spectrum of lesions that may simulate soft tissue neoplasms are described, with their radiologic appearances. The cellular nature of the matrix of a lesion cannot be identified absolutely as neoplastic by current imaging methods. Although sonography and magnetic resonance imaging can each produce valuable diagnostic information hitherto not provided by imaging the soft tissues, they do not per se show evidence of neoplasia. The differentiation of the two types of tumor, neoplastic and non-neoplastic, can only be achieved by a combination of clinical, radiologic and histologic information. Ultimately, biopsy with histologic examination may be required for the definitive diagnosis. 相似文献
7.
Rehan Asif Kamlesh Chandra Vanita Chopra M. L. B. Bhatt 《Indian journal of otolaryngology and head and neck surgery》2003,55(2):94-96
Management of Head and Neck Cancers poses a challenge inspite of several advances because of poor success in terms of response
rate, survival and reduced morbidity of the patients. In the present study 30 untreated histologically proven cases of head
and neck cancers were subjected to weekly radiotherapy with adjuvant chemotherapy (cisplatin 30 mg/m2 intravenously). This study group was compared with a group of 30 patients who were given only radiotherapy. Results have
shown that combination of chemotherapy with radiotherapy gives a significantly better results in tumour as well as nodal response
with minimal toxicities. 相似文献
8.
目的 探讨吸烟、饮酒与胆道癌的关系。方法 采用全人群病例对照研究 ,研究对象为 1997年6月 1日~ 2 0 0 1年 5月 31日期间确诊的、年龄在 35~ 74岁的上海市区 6 2 7例胆道癌新发病例以及按性别、年龄 (5岁一组 )频数配对的 95 9例人群对照。采用非条件logistic回归模型分析吸烟、饮酒与胆道癌的关系。结果 男性中 ,吸烟对肝外胆管癌和壶腹癌各组的调整OR均大于 1,现仍吸烟者的调整OR分别为 1.5 1(95 %CI:0 .86~ 2 .6 6 ) ,1.5 8(95 %CI:0 .6 9~ 3.5 8) ;OR随吸烟年限增加和开始吸烟年龄提早有所升高 ,但均未达显著水平。饮酒对胆道癌各组OR均无统计学意义。结论 吸烟也许与肝外胆管癌、壶腹癌有联系 ,未发现吸烟与胆囊癌的显著性关联 ;未发现饮酒与胆道癌的显著性关联。 相似文献
9.
目的探讨胆囊癌与妊娠的关系.方法采用全人群病例对照研究,研究对象为1997年6月1日~2001年5月31日期间确诊、年龄在35~74岁的上海市区女性胆囊癌269例以及按年龄(5岁一组)频数配对的538名人群对照,采用非条件lo-gistic回归模型分析妊娠与胆囊癌的关系.结果胆囊癌合并胆石症者中,与妊娠次数≤2次者比较,妊娠次数(3次,4次,5次及≥6次)的各组调整OR分别为1.33(95%CI:0.59-2.99),1.34(95%CI:0.58-3.11),1.39(95%CI:0.57-3.43)和2.67(95%CI:1.12-6.41),趋势检验P=0.03.结论多次妊娠可能通过胆石症影响胆囊癌的发生,生育因素导致的女性体内雌、孕激素水平的升高可能在胆囊癌病因学中起一定的作用. 相似文献
10.
目的:探讨身体质量指数(BMI)、腰臀围比(WHR)与胆道癌的关系.方法:采用非条件logistic回归模型分析身体质量指数、腰臀围比与胆道癌的关系.结果:与正常BMI组比较,胆囊癌女性20~29岁、30~39岁肥胖组的OR与趋势检验均达到或接近显著水平.与腰臀围比四分位最低组比较,胆囊癌和肝外胆管癌男女性最高四分位组OR和趋势检验均达到显著水平.结论:青年时期肥胖可能会增加胆囊癌的发病风险;腰臀围比也是胆囊癌和肝外胆管癌独立的危险因素. 相似文献