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51.
Polychlorinated biphenyls (PCBs) contamination that has resulted from the recycling of electronic power capacitors and transformers could lead to deterioration in soil quality and high ecological risk. As microorganisms are generally considered to be the best indicators of soil pollution, the diversity of bacterial communities in the soil around an e-waste recycling workshop in the Taizhou e-waste recycling area of China was studied using denaturing gradient gel electrophoresis (DGGE). The results indicated that the PCBs content in the soil decreased with increasing distance from the recycling workshop. Moreover, a gradual change in soil bacteria diversity along the PCBs pollution gradient was observed. Furthermore, the predominance of Proteobacteria and Bacteroidetes was found on the basis of sequence analysis and some highly similar subsequences of microorganisms were also found to be closely related to the catabolism of PCBs and other organic compounds. In a word, our results indicated that PCBs pollutants had an evident impact on the structure of the soil microbial community and the enriched microbes might serve to decompose PCBs in soil.  相似文献   
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53.

Background

Specific morphologic features of hepatocellular carcinoma (HCC) on imaging have identifiable pathologic correlates as well as implications for altering surgical management and defining prognosis. In this study, we compared susceptibility-weighted imaging (SWI) to conventional techniques and correlated our findings with histopathology to determine the role of SWI in assessing morphologic features of HCC without using a contrast agent.

Methods

86 consecutive patients with suspected HCC were imaged with MRI (including T1, T2, T2*, and SWI) and subsequently CT. 59 histologically-proven HCC lesions were identified in 53 patients. Each lesion on each imaging sequence was evaluated by two radiologists, and classified with respect to lesion morphology, signal intensity relative to surrounding hepatic parenchyma, presence of a pseudocapsule, presence of venous invasion, and internal homogeneity.

Results

Histopathology confirmed pseudocapsules in 41/59 lesions. SWI was able to detect a pseudocapsule in 34/41 lesions; compared to conventional T1/T2 imaging (12/41) and T2* (27/41). Mosaic pattern was identified in 25/59 lesions by histopathology; SWI confirmed this in all 25 lesions, compared to T1/T2 imaging (13/25) or T2* (18/25). Hemorrhage was confirmed by histopathology in 43/59 lesions, and visible on SWI in 41/43 lesions, compared to T1/T2 (7/43) and T2* (38/43). Venous invasion was confirmed by histopathology in 31/59 patients; SWI demonstrated invasion in 28/31 patients, compared to T1/T2 (7/31) and T2* (24/31).

Conclusions

SWI is better at identifying certain morphologic features such as pseudocapsule and hemorrhage than conventional MRI without using a contrast agent in HCC patients.  相似文献   
54.

Background

The molecular mechanisms underlying the development and progression of gastric carcinoma remain poorly understood. The main objective of this study was to investigate the expression level of targeting protein for Xenopus kinesin-like protein 2 (TPX2) and its clinical significance in human gastric carcinoma.

Methods

Real-time quantitative polymerase chain reaction (RT-PCR) and western blotting were used to determine the mRNA and protein levels of TPX2 in 20 paired gastric carcinoma tissues and the adjacent normal tissues, and the expression of TPX2 protein in 106 specimens of a gastric carcinoma tissue microarray was determined by immunohistochemistry. The associations of TPX2 expression with the clinicopathological features were analyzed, and the prognosis of gastric carcinoma patients was evaluated.

Results

The results showed that the expression of TPX2 mRNA was significantly higher in gastric carcinoma than in the adjacent normal tissues in 20 paired samples. Western blotting analysis revealed that TPX2 protein was differentially increased in 17 of 20 specimens from primary human gastric carcinoma tissues compared with those from adjacent non-tumor tissues. Immunohistochemical staining showed that TPX2 over-expression was significantly associated with advanced age (P = 0.001) and tumor T stage (P = 0.003). In addition, TPX2 was an independent prognostic factor for overall survival (OS) in the multivariate analysis [hazard ratio (HR) 0.001; 95 % confidence interval (CI) 2.626–7.198; P = 0.001].

Conclusions

TPX2 is up-regulated in gastric carcinoma and is associated with old age and tumor T stage. TPX2 may serve as a good prognostic indicator in patients with gastric carcinoma.
  相似文献   
55.
The standard ‘General requirements for stem cells’ is the first set of general guidelines for stem cell research and production in China, jointly drafted and agreed upon by experts from the Chinese Society for Stem Cell Research. This standard specifies the classification, ethical requirements, quality requirements, quality control requirements, detection control requirements and waste disposal requirements of stem cells, which is applicable to stem cell research and production. It was firstly released by the Chinese Society for Cell Biology on 1 August 2017 and was further revised on 30 April 2020. We hope that publication of these guidelines will promote institutional establishment, acceptance, and execution of proper protocols, and accelerate the international standardization of stem cells for clinical development and therapeutic applications.  相似文献   
56.
Abstract

This study aimed to evaluate the total Cr and Cr(VI) contamination levels and assess the possible health risk of Cr(VI) in soils from a coal chemical industrial area in Northwest China. The contamination factor (CF) was used to calculate the total Cr and Cr(VI) contamination levels in soils from the study area. The highest concentration of Cr(VI) (69.58?mg/kg) was found in the top soil (0–20?cm) with the distance of 10 m to the coal cinder heap. The carcinogenic risk (CR) and hazard quotient (HQ) were estimated for health risk to workers by using “Chinese Technical Guidelines for Risk Assessment of Contaminated Sites (HJ 25.3-2014).” The results showed that the soils from the study area were moderately polluted by the total Cr and Cr(VI). There was no serious non-CR (HQ < 1). However, the CR values of Cr(VI) were significantly higher than the threshold value, indicating that workers are facing serious threat of Cr(VI). Inhalation (70.32%) was the main exposure pathway to CR, followed by dermal contact (20.64%), and then ingestion (9.04%). These results provide basic information of Cr(VI) pollution control and environment management in coal chemical industrial areas.  相似文献   
57.
通过分析21所高等师范院校生物科学专业毕业学年的课程设置现状.并对325名生物科学专业的大四学生进行问卷调查,反映出目前高等师范院校毕业学年课程设置存在的问题,提出优化措施应体现在:增加教育类课程,强化教学技能训练;延长实习时间,加强实习指导;强化中学教材教法课程建设;开设与中学教学关系密切的专业基础提高课程和专业选修课程。  相似文献   
58.
运动形式的适应性演化与生物的捕食、防御、繁殖和通讯等生存行为紧密相关.哺乳动物演化出的多种多样的运动方式对占领新栖息地和获取新生存资源有着举足轻重的作用,其中滑翔和飞行能力是哺乳动物为适应环境而演化出的特殊运动形式,该类群动物已成为适应性演化研究的热点模型之一.为了适应生存,滑翔和飞行哺乳动物在形态、生理和行为方面都发...  相似文献   
59.

Background

Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is a common condition affecting men of all ages. Acupuncture may be an effective treatment option for CP/CPPS, but evidence is limited. We propose to evaluate the effectiveness of acupuncture in a rigorously conducted trial.

Methods

Ten hospitals will recruit 440 participants with CP/CPPS in China from October 2017 to December 2019. Participants will be randomly allocated to acupuncture or sham acupuncture with a 1:1 ratio using computerized simple random sampling. The whole study consists of 2-week baseline, 8-week treatment, and 24-week follow up. Twenty 30-mintute sessions of acupuncture or sham acupuncture treatment will be provided between week 1 and 8. The two co-primary outcomes are the proportion of responders at week 8 and week 32. Secondary outcomes include proportion of responders in the two groups at different time points; change in the National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI) total score; change in the NIH-CPSI subscales; change in the International Prostate Symptom Score; change in the Hospital Anxiety and Depression Scale; expectation assessments; proportions of participants in each response category of the Global Response Assessment; change in the International Index of Erectile Function 5; change in the five-level EuroQol five-dimensional questionnaire and a visual analogue scale; and changes in peak and average urinary flow rate.

Discussion

This study will provide robust evidence on whether acupuncture is effective for relieving symptoms of CP/CPPS.

Trials registration

ClinicalTrials.gov, NCT03213938. Registered on 5 July 2017.
  相似文献   
60.
PURPOSE: To validate Gaussian normalized cerebral blood volume (GN-nCBV) by association with overall survival (OS) in newly diagnosed glioblastoma patients and compare this association with current standard white matter normalized cerebral blood volume (WN-nCBV). METHODS: We retrieved spin-echo echo-planar dynamic susceptibility contrast MRI acquired after maximal resection and prior to radiation therapy between 2006 and 2011 in 51 adult patients (28 male, 23 female; age 23-87 years) with newly diagnosed glioblastoma. Software code was developed in house to perform Gaussian normalization of CBV to the standard deviation of the whole brain CBV. Three expert readers manually selected regions of interest in tumor and normal-appearing white matter on CBV maps. Receiver operating characteristics (ROC) curves associating nCBV with 15-month OS were calculated for both GN-nCBV and WN-nCBV. Reproducibility and interoperator variability were compared using within-subject coefficient of variation (wCV) and intraclass correlation coefficients (ICCs). RESULTS: GN-nCBV ICC (≥0.82) and wCV (≤21%) were superior to WN-nCBV ICC (0.54-0.55) and wCV (≥46%). The area under the ROC curve analysis demonstrated both GN-nCBV and WN-nCBV to be good predictors of OS, but GN-nCBV was consistently superior, although the difference was not statistically significant. CONCLUSION: GN-nCBV has a slightly better association with clinical gold standard OS than conventional WM-nCBV in our glioblastoma patient cohort. This equivalent or superior validity, combined with the advantages of higher reproducibility, lower interoperator variability, and easier automation, makes GN-nCBV superior to WM-nCBV for clinical and research use in glioma patients. We recommend widespread adoption and incorporation of GN-nCBV into commercial dynamic susceptibility contrast processing software.  相似文献   
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