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21.
目的 分析1999和2010年哈尔滨7 ~18岁儿童青少年身材比例的变化特点,为及时识别或发现身体的生长异常提供基础数据.方法 1999,2010年分别对分层整群抽取的哈尔滨市城区7~18岁3 162名,3 971名学生进行身高、坐高、腓骨点高等指标的测量,并统计分析.结果 哈尔滨城市男女学生身高、坐高、小腿长随着年龄增加而增长,2010年各指标值高于1999年.1999,2010年哈尔滨城市男女学生坐高/腿长变化随年龄增长逐渐下降,15岁以后基本稳定,但1999年多于半数的年龄组此值大于2010年.1999和2010年,1O岁之后女生坐高/腿长均高于男生.1999年与2010年哈尔滨城市男女学生小腿长/腿长集中在0.52 ~0.54之间;男、女生差异不明显.结论 近11 a来,哈尔滨7~ 18岁城市男女学生身高、坐高、小腿长均有所增长;坐高/腿长在青春期前性别和年份差异不明显,青春期后女性略高于男性;小腿长/腿长不存在明显的年份和性别差异. 相似文献
22.
Shuying Li Xiaojuan Zhao Zhiwei Wu Ye Li Lin Zhu Binbin Cui Xinshu Dong Suli Tian Fulan Hu Yashuang Zhao 《Familial cancer》2013,12(4):755-765
Cyclooxygenase-2 (COX-2), 12-lipoxygenase (12-LOX) and phospholipaseA2 (PLA2) played important roles in the modulation of apoptosis, angiogenesis, carcinogenesis and invasion of colorectal cancer (CRC). The polymorphisms in COX-2, 12-LOX and PLA2 may affect their roles. Therefore, we investigated if COX-2 ?1195G > A, 12-LOX 261Arg > Gln and PLA2 c.349 + 191A > G polymorphisms were associated with risk and prognosis of CRC as well as possible interactions with the environmental factors on the risk of CRC in Northeast of China. A case–control study with 451 cases and 631 controls were carried out, a cohort with 386 patients were followed up. Genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Compared with the 261Arg/Arg genotype, 12-LOX 261Arg/Gln genotype and 261Arg/Gln + Gln/Gln genotypes reduced the risk of rectal cancer by 33 % (adjusted OR = 0.67, 95 % CI 0.47–0.97, p = 0.03) and 32 % (adjusted OR = 0.68, 95 % CI 0.49–0.96, p = 0.03), respectively. The adjusted HR for the association between 12-LOX 261Gln/Gln genotype and overall survival in patients with CRC was 1.68 (95 % CI 1.06–2.68, p = 0.03). There was also evidence of an interaction between the PLA2 c.349 + 191 A > G genotypes and the overnight food consumption (adjusted ORi = 1.92, 95 % CI 1.14–3.25, P interaction = 0.01). These observations indicate that 12-LOX 261Arg > Gln polymorphism may affect risk of rectal cancer, and it may be a potential predictive marker for prognosis of CRC. 相似文献
23.
Jia Yu Hong-Wei Dong Li-Tian Shi Hui-Ling Jiang Jian-Wen Yu Qian-Wen Zhao Shi-Chun Cai Dan Han Xuan-Yue Tang Jia-Ren Liu 《Archives of environmental contamination and toxicology》2013,65(1):78-88
The Songhua River, in northeast China, has heavy organic contamination due to domestic sewage and industrial wastewater. Thus, it is important to further determine its genotoxic activity, which is a potential hazard for human health. Short-term genotoxic bioassays using Salmonella, the cytokinesis-block micronucleus cytome assay, and mouse liver cell comet assay were employed to further examine the genotoxic activity of diethyl ether extracts of water samples taken from the Songhua River. Ames test results showed that there were still frame-shift mutagens, both direct and indirect, in water samples at doses of 5.0 or 7.0 L water equivalent/plate. The mutagenicity seems to be less when compared with the results from 2002 to 2003. A dose–response relationship was also obtained between DNA damage in mouse liver cells by comet assay and micronuclei formation by CBMN assay. These results indicate that the water samples showed genotoxic activity with a mutagenic potency. 88 and 104 compounds, respectively, were identified in summer and winter water sample extracts by gas chromatography–mass spectrometry analysis. Four priority pollutants listed by the United States Environmental Protection Agency and six priority pollutants listed by the Chinese Environment Protection Agency were found in summer or winter water samples, respectively. The results indicate that the diethyl ether extracts of surface water samples taken from the Songhua River still show genotoxic activity (≥3.0 L water). The risks of potential carcinogenicity for human health in the Songhua River should be studied further. 相似文献
24.
《Vaccine》2018,36(52):8079-8083
Erysipelothrix rhusiopathiae is the causative agent of animal erysipelas and human erysipeloid. Bacterial surface proteins are promising vaccine candidates. We recently identified 3 E. rhusiopathiae surface proteins (GAPDH, HP0728, and HP1472) and characterized their roles as virulence factors. However, their efficacy as protective antigens is still unknown. The N-terminal region of a previously identified surface protein, CbpB (CbpB-N), is speculated to be a protective antigen, but this needs to be verified. The aim of this study was to evaluate the protective efficacy of GAPDH, HP0728, HP1472, and CbpB-N. Immunization with recombinant GAPDH provided complete protection in a mouse model, recombinant CbpB-N provided partial protection, while recombinant HP0728 and HP1472 provided no protection. Recombinant GAPDH also provided good protection in a pig model. GAPDH antiserum exhibited significant blood bactericidal activity against E. rhusiopathiae. In conclusion, GAPDH and CbpB-N were found to be protective antigens of E. rhusiopathiae, and GAPDH is a promising vaccine candidate. 相似文献
25.
《Drug metabolism and pharmacokinetics》2019,34(3):187-193
Mandelic acid (MA) is generally used as a biomarker of the exposure of styrene, which is classified as a class of hazardous environmental pollutants, and also used as an important chiral intermediate in pharmaceutical industry. The previous studies have found the excretion of phenylglyoxylic acid (PGA) in human and rat, a metabolite of MA, was mainly from S-MA rather than R-MA. The metabolic mechanism, however, is not clear. In order to explore the possible metabolic mechanism, the enzyme types involved in the stereoselectivity metabolism of MA were firstly studied, and then human and rat long-chain 2-hydroxy-acid oxidase 2 (HAO2) were recombinantly expressed to study the metabolic profiles of S-MA and its analogues. The results indicated that HAO2 might catalyze the stereoselectivity metabolism of S-MA in rats. Human HAO2 (hHAO2) and rat HAO2 (rHAO2) isozymes β1 and β2 were successfully cloned and expressed with high purity and good enzyme activities. The enzyme kinetic profiles of these enzymes were different for S-MA and analogues. The order of catalytic efficiency for hHAO2 and rHAO2, however, was reverse. It might be relevance to the difference in active amino acid residues and loop 4 in human and rat L-2-hydroxy acid oxidase isozyme B crystal structures. 相似文献
26.
27.
Microsporidia are composed of a highly diverse group of single-celled, obligate intracellular fungi that colonize an extremely wide range of other eukaryotes, among which Enterocytozoon bieneusi is the most common species responsible for human microsporidiasis. Genotyping of E. bieneusi based on sequence analysis of the ribosomal internal transcribed spacer (ITS) has recognized ~500 genotypes in humans and a great variety of other mammals and birds. Those genotypes vary in genetic or hereditary characteristics and form 11 genetic groups in phylogenetic analysis of the ITS nucleotide sequences. Some of genotypes in Group 1 (e.g., D, EbpC, and type IV) and Group 2 (e.g., BEB4, BEB6, I, and J) have broad host and geographic ranges, constituting a major risk for zoonotic or cross-species transmission. By contrast, host specificity seems common in Group 3 to Group 11 whose members appear well adapted to specific hosts and thus would have minimal or unknown effects on public health. Multilocus sequence typing using the ITS, three microsatellites MS1, MS3, and MS7, and one minisatellite MS4, and population genetic analysis of Group 1 isolates reveal the occurrence of clonality, potential host adaptation, and population differentiation of E. bieneusi in various hosts. Nonetheless, it is still highly desirable to explore novel genetic markers with enough polymorphisms, to type complex or unstructured E. bieneusi populations of various host species and geographic origins, notably those belonging to Group 2 to Group 11. Additional population genetic and comparative genomic data are needed to elucidate the actual extent of host specificity in E. bieneusi and its potential impacts on zoonotic or interspecies transmission of microsporidiasis. 相似文献
28.
Fábio Andrey da Costa Araújo Thiago de Santana Santos Hécio Henrique Araújo de Morais José Rodrigues Laureano Filho Emanuel Dias de Oliveira e Silva Ricardo José Holanda Vasconcellos 《Journal of cranio-maxillo-facial surgery》2012,40(8):e346-e349
The aim of this prospective, randomized, controlled, paired trial was to perform a comparative analysis of the preemptive analgesic effect of nimesulide and tramadol chlorhydrate during third molar surgery. The study was carried out between March and November 2009, involving 94 operations in 47 male and female patients with bilateral impacted lower third molars in comparable positions. The sample was divided into two groups. Group A received an oral dose of 100 mg of nimesulide 1 h prior to surgery. Group B received an oral dose of 100 mg of tramadol chlorhydrate 1 h prior to surgery. The following aspects were evaluated in the postoperative period: adverse effects of the drugs; amount of rescue medication used (acetaminophen 750 mg); and pain 5, 6, 24, 36, 48, 60, 72 and 84 h after surgery using a visual analog pain scale. Peak pain occurred 5 h after surgery in both groups, with a mean pain score of 2.3 in Group A and 3.0 in Group B; this difference did not achieve statistical significance (p > 0.141). Based on the sample studied, nimesulide and tramadol chlorhydrate demonstrate similar preemptive analgesic effects when used in lower third molar surgeries. 相似文献
29.
30.
A research for the relationship between human papillomavirus and human uterine cervical carcinoma 总被引:8,自引:0,他引:8
Jingyi Si Kun Lee Ricai Han Wei Zhang Bingbing Tan Guoxing Song Shide Liu Lianfong Chen Weiming Zhao Liping Jia Yongyan Mai Yi Zeng Yinan Zhou Yuezhu Wang Jian Ling Yu Sun Xiangjin Meng Zhangfong Yu Liming Pu 《Journal of cancer research and clinical oncology》1991,117(5):454-459
Summary Biopsies from 318 cases with squamous cell carcinoma of the uterine cervix, 48 with cervical and vulvar condylomata, 14 with cervical intraepithelial neoplasia (CIN), 34 with chronic cervicitis and 24 with normal cervical epithelium were collected from different geographic regions with different cervical cancer mortalities. The DNA · DNA dot-blot and Southern blot hybridization results show that there is a close relationship between HPV-16 and the uterine cervical squamous cell carcinoma in China. One very interesting observation is that the finding of HPV-16-homologous DNA differs significantly among five geographic regions, and corresponds with the mortalities from cervical cancer of these five regions. HPV-11 was found mainly in benign lesions. The rate of detection of HPV-16 in Chinese women increased from 8.3% in normal cervical epithelium to 20% in chronic cervicitis, 28% in cervical condyloma, 50% in CIN and 60.4% in cervical cancer. It is suggested that HPV-16 infection may be an etiological factor in the development of human cervical carcinoma. From the results of Southern blot hybridization, it appeared that HPV-16 DNA had been integrated into the genome of the host cell in cervical cancer. Whereas the HPV-16 DNA sequence was only present as an episome in normal cervical epithelium and cervical benign lesions. The rate of occurence of E6-E7 genes is the highest (88.9%) compared with that of other subgenomic fragments of HPV-16 in specimens of human cervical cancer in China. This implies that E6 and E7 may be the oncogenic genes of HPV-16 and play an important role in the carcinogenesis of human cervical epithelial cells. The amplification and rearrangement of the c-myc protooncogene are closely associated with the occurrence of cervical cancer. The results presented here revealed that the activated c-myc oncogene may cooperate with HPV-16 in the carcinogenic processes.Abbreviations HPV
Human papillomavirus
- CIN
cervical intraepithelial neoplasia
- SSC
standard saline citrate 相似文献