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11.
Ling Zhang Dandan Zhang Baowen Yu Shangbo Wang Yanlin Liu Jian Wang Xin Li Xiaoyun Shang Hongyuan Li 《PloS one》2013,8(3)
Objective
To assess the prevalence of HIV infection and characteristically risk of factors which associated with HIV infection among MSM in Harbin, China.Methods
A face-to-face questionnaire interview was conducted among 463 Men Who Have Sex with Men (MSM) who were recruited by the snowball sampling in Harbin from April, 2011 to July, 2011. The questionnaire mainly included demographics, AIDS knowledge, homosexual behavior and the status of intervention in MSM. Blood specimens were obtained and tested for the diagnoses of HIV, syphilis and hepatitis C virus (HCV). Associations between above exposed factors and HIV infection were analyzed using a univariate analysis and forward stepwise logistic regression.Results
The prevalence of HIV and syphilis was 9.5 and 14.3%. The awareness rate of AIDS was 86.8%. The rate of unprotected sexual behavior was 57.6% of MSM during the past 6 months. The univariate analysis identified that the age (age≥35 years old), cohabitation, more than 10 years of homosexual behavior and more than 10 homosexual partners were risk factors which associated with the HIV infection, and that protected sex during the past 6 months was a protective factor for the HIV infection. The multivariate analysis identified that the duration of homosexual behavior and commercial sexual behavior were independent risk factors which associated with the HIV infection, and the protected sex during the past 6 months was a protective factor for the HIV infection.Conclusion
The prevalence of HIV among MSM in Harbin has been rapidly increasing in the past few years. Targeted, tailored, and comprehensive interventions are urgently needed to prevent the HIV infection from MSM. 相似文献12.
The western Ordos Plateau is a key area of shrub diversity and a National Nature Reserve of endangered shrub species in north-west China. Desert expansion is becoming the most important threat to these endangered species. However, little is known about the effects of sand burial on the dynamics of the shrub community. This study aims to investigate how the shrubs as a community and as different individual shrubs respond to the disturbances caused by the desert expansion. The approach used by this study is to separate the seed-dispersal strategy from the sand-burial forces that are involved in structuring the shrub communities at different disturbance stages. Four communities for different disturbance stages were surveyed by using 50×50 m plots. The individual shrubs were classified into coloniser and successor groups at the seed-dispersal stage and strong and weak sand-burial tolerance groups at the sand-expansion stage. We employed spatial point pattern analysis with null models for each community to examine the seed-dispersal strategy and sand-burial forces affecting community distribution patterns. At the seed-dispersal stage, the interactions between the colonisers and the successors showed significant positive correlation at a scale of 0–1 m and significant negative correlation at a scale of 2 m; significant negative correlations between the groups with strong and weak sand-burial tolerance in the early stage of sand expansion at scales of 3–6 m, and significant positive correlation in the later stage of sand expansion at a scale of 13 m, were found. Seed-dispersal strategy is a reasonable mechanism to explain the shrub community pattern formation in the earlier stages, whereas sand burial is the primary reason for the disappearance of shrubs with weak sand-burial tolerance, this irreversible disturbance causes homogenisation of the community structure and produces aging populations of shrub species. This has an important influence on the succession direction of desert shrub communities. 相似文献
13.
Bin Sun Xiaofeng Zhang Xianshuo Cheng Yu Zhang Lei Chen Lehua Shi Zhenyu Liu Haihua Qian Mengchao Wu Zhengfeng Yin 《PloS one》2013,8(11)
Hepatic stellate cells (HSCs), a specialized stromal cytotype in the liver, have been demonstrated to actively contribute to hepatocellular carcinoma (HCC) development. However, the previous studies were performed using HSC cell lines, and the prognostic value of intratumoral HSCs (tHSCs) was unclear. Here we isolated tHSCs from fresh human HCC tissues, and analyzed the abilities of tHSCs to promote HCC progression by using in vitro assays for cell viability, migration and invasion as well as epithelial-mesenchymal transition (EMT) phenotype. 252 HCC patients who underwent hepatectomy were enrolled for analysis of tHSCs and E-cadherin expression in tumor tissues, and 55 HCC patients for analysis of tHSCs in tumor tissues and circulating tumor cells (CTCs) in blood. Prognostic factors were then identified. The results showed that coculture of tHSCs with HCC cells had a stronger effect on HCC cell viability, migration and invasion, accompanied with the acquisition of epithelial-mesenchymal transition (EMT) phenotype. In vivo cotransplantation of HCC cells with tHSCs into nude mice more efficiently promoted tumor formation and growth. Icaritin, a known apoptosis inducer of HSCs, was demonstrated to effectively inhibit tHSC proliferation in vitro and tHSC-induced HCC-promoting effects in vivo. Clinical evidence indicated that tHSCs were rich in 45% of the HCC specimens, tHSC-rich subtypes were negatively correlated either with E-cadherin expression in tumor tissues (r = -0.256, p < 0.001) or with preoperative CTCs in blood (r = -0.287, p = 0.033), and were significantly correlated with tumor size (p = 0.027), TNM staging (p = 0.018), and vascular invasion (p = 0.008). Overall and recurrence-free survival rates of tHSC-rich patients were significantly worse than those for tHSC-poor patients. Multivariate analysis revealed tHSC-rich as an independent factor for overall and recurrence-free survival. In conclusion, tHSCs provide a promising prognostic biomarker and a new treatment target for HCC. 相似文献
14.
Objective
The purpose of this study was to analyze the clinical features and prognostic factors of surgical outcome of foot drop caused by lumbar degenerative disease and put forward the clinical stage.Methods
We retrospectively reviewed 135 patients with foot drop due to lumbar degenerative disease. The clinical features and mechanism were analyzed. Age, sex, duration of palsy, preoperative muscle strength of tibialis anterior (TA), sensation defect of affected lower limb, affected foot, diagnosis and compressed nerve roots were recorded and compared with surgical outcome.Results
Foot drop was observed in 8.1% of all inpatients of lumbar degenerative disease. L5 nerve root compression was observed in 126 of all 135 patients (93.3%). Single, double and triple roots compression was observed respectively in 43, 83, and 9 patients (31.9%, 61.5%, and 6.6%). But there was no significant relationship between preoperative muscle strength of TA and the number of compressed roots. The muscle strength of TA was improved in 113 (83.7%) patients after surgery, but it reached to >=4 in only 21 (15.6%) patients. Improvement of the muscle strength of TA was almost stable at the 6-month follow-up. At the last follow-up, the muscle strength of TA was 1, 2, 3, 4, 5 respectively in 28, 24, 62, 13, 8 patients. Multivariate logistic regression showed duration of palsy (p=0.0360, OR=2.543), preoperative muscle strength of TA (p=0.0064, OR=5.528) and age (p=0.0309, OR=3.208) were factors that influenced recovery following an operation.Conclusions
L5 nerve root was most frequently affected. The muscle strength of TA improved in most patients after surgery, but few patients can get a good recovery from foot drop. Patients of shorter duration of palsy, better preoperative muscle strength of TA and younger age showed a better surgical outcome. 相似文献15.
16.
Hui-Min Zhang Jian-Fang Li Min-Chen Wu Hong-Ling Shi Cun-Duo Tang 《Annals of microbiology》2013,63(1):307-313
Amino acids and dipeptides that are correlated significantly with lipase optimum temperatures were searched for in 34 microbial lipase sequences by a stepwise regression method. The positive dipeptides were found to be IR, KS, NY, SA, ST and YR, whereas negative ones were DK, DY, IS, KA, WS, YS and QI. The calculated optimum temperatures from an optimal regression equation of dipeptides fitted the corresponding experimental optimum temperatures of lipases very well, and the maximal absolute difference was only 3.43°C. The spatial positions of the related dipeptides were searched for in two known crystal structures of a thermophilic and mesophilic lipase, respectively. Most of the positive dipeptides were sited in the α-helices, while the negative ones were located mainly in the β-strands or coils and about half of them existed in the N- or C-terminii of the lipases. The results obtained will be very useful in lipase engineering for enhancing lipase thermostability. 相似文献
17.
Long Huiping Zhong Gang Wang Chengzhi Zhang Jian Zhang Yueling Luo Jinglian Shi Shengliang 《Neurochemical research》2019,44(8):1830-1839
Neurochemical Research - The pathogenesis of late-onset Alzheimer's disease (LOAD) mainly involves abnormal accumulation of extracellular β-amyloid (Aβ) and the consequent neurotoxic... 相似文献
18.
Zhao Dawei Wu Di Zhang Gengyue Li Yongqi Shi Weiguo Zhong Bohua Yu Hong 《Molecular biology reports》2022,49(9):8359-8368
Molecular Biology Reports - Irinotecan (CPT-11) is a camptothecin derivative whose potent anti-tumor activity depends on the rapid formation of an in vivo active metabolite, SN38... 相似文献
19.
Long Jun-Yi Wang Xue-Jun Li Xiao-Ying Kong Xie-He Yang Guang Zhang Dan Yang Yan-Ting Shi Zheng Ma Xiao-Peng 《Neurochemical research》2022,47(3):545-551
Neurochemical Research - Chronic visceral pain (CVP) is one of the common symptoms of many diseases triggered by underlying diseases of the internal organs of the human body. Its causes include... 相似文献
20.
Cai Tiantian Yao Wendong Qiu Lei Zhu Austin Rui Shi Zheng Du Yi 《Molecular biology reports》2022,49(5):3693-3704
Molecular Biology Reports - It has been reported that Pleckstrin 2 (PLEK2) acts as an oncogene in non-small cell lung cancer (NSCLC). Bromodomain containing protein 4 (BRD4), an important... 相似文献