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51.
The effects of airborne particulate matter (PM) trace elements on health are widely concerned nowadays. Many achievements have been made while many unknowns exist. This article reports the recent research progresses, describes the effects of exposure to PM trace elements on health epidemiological evidence, toxicology findings, and raises some questions for future studies.  相似文献   
52.
PICC常见并发症产生原因及护理   总被引:1,自引:0,他引:1  
潘丽花  于兰贞 《护理研究》2006,20(29):2633-2635
介绍了PICC常见并发症,如导管阻塞、导管断裂、空气栓塞、导管相关性血栓形成、导管相关性感染、静脉炎、液体外渗的产生原因及护理措施。  相似文献   
53.
Inulin was fermented by adult faecal microbiota and 10 exogenous strains for 24 or 48?h. The contents of acetate, propionate, butyrate and lactate were quantified in the fermented products, and the growth-inhibitory and apoptosis-inducing effects on a human colon cell line (HCT-116 cells) were assessed. Most of these strains increased contents of acetate, propionate and butyrate, and promoted lactate conversion. Correlation analysis suggested that butyrate and lactate in the fermentation products were positively and negatively correlated with the measured inhibition ratios (p?via inducing DNA fragmentation and increasing total apoptotic populations in the treated cells. Moreover, the fermentation products with higher growth-inhibitory activities demonstrated the increased apoptosis-inducing properties. In conclusion, these strains could cooperate with adult faecal microbiota to confer inulin fermentation products with higher anti-colon cancer activity.  相似文献   
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55.
The majority of salivary gland tumors are of epithelial origin. Parotid gland is the most common location of the tumors. Surgery is the main modality for the management of parotid tumors. Radiotherapy, chemotherapy etc are the auxiliary modalities.  相似文献   
56.
目的:探讨不同排牙法的全口义齿咀嚼效能的异同。方法:采用上颌排牙法、下颌排牙法和综合排牙法为10名无牙颌患者分别制作3副全口义齿。戴用3个月后,通过吸光度法测定咀嚼效率,比较不同排牙法的全口义齿咀嚼效能的异同,并与有牙颌进行对比。结果:在单侧咀嚼和双侧咀嚼2种咀嚼方式下,全口义齿患者的咀嚼次数和咀嚼效能均少于有牙颌组,本实验3组全口义齿在3个月后均发挥了良好的咀嚼效能。下颌排牙法和综合排牙法全口义齿的咀嚼次数和咀嚼效能无统计学差异,但均好于上颌排牙法全口义齿。结论:下颌排牙法和综合排牙法的全口义齿排列的人工牙能够减少在咀嚼过程中不利于全口义齿稳定因素的影响,提高咀嚼效能。  相似文献   
57.
58.
目的:观察小鼠釉质发育过程中成釉器中间层细胞的增殖、凋亡和其组织非特异性碱性磷酸酶(tissue nonspecific alkaline phosphatase,TNSALP)的表达,探讨中间层在釉质形成过程中的可能作用.方法:取出生后1、3、5、7、9、11、15d的BALB/c小鼠56只,解剖分离含下颌第一磨牙区的下颌骨,脱钙,制片,HE染色进行牙釉质发育情况的组织学观察,分别采用原位末端标记法(TUNEL法)、SP免疫组织化学技术、PV二步法观察中间层细胞的凋亡及检测Bcl-2、增殖细胞核抗原(proliferating cell nuclear antigen,PCNA),并对TNSALP进行组织学定位.通过Image-pro plus 6.0图像分析软件.对图像进行半定量分析.采用SPSS13.0软件包进行t检验、单因素方差分析及SNK-q检验.结果:出生后1d.中间层细胞增殖细胞核抗原由比成釉细胞表达高的强阳性表达逐渐降低;至7d时,其表达为阴性,而且中间层细胞随釉质的发育逐渐凋亡.中间层细胞先于成釉细胞表达TNSALP,出生后5d时即呈现强阳性染色,而后其表达又逐步减弱;成釉细胞7d时开始出现阳性,且呈逐渐增强趋势.结论:中间层细胞的增殖和凋亡及其TNSALP的表达与成釉细胞具有相关性,提示中间层细胞有可能参与成釉细胞的分化及釉质形成.  相似文献   
59.
Multiple endocrine neoplasia (MEN) type 2B is the rarest and most aggressive form of MEN syndrome. MEN 2B patients manifest characteristic oral and facial features besides the neural crest cell-derived tumors, including medullary carcinoma, pheochromocytoma, mucosal neuroma, and ganglioneuromatosis of the gut. We report a case of MEN 2B diagnosed on the basis of the warning signs of mucosal neuroma and multiple neural hyperplasias in the maxillary bone resected during orthognathic surgery. A subsequent systemic examination under the pathologic diagnosis of neural lesions revealed medullary thyroid carcinoma, megacolon, thickened corneal nerves, and RET gene mutation, thus verifying the diagnosis of MEN 2B. An immunohistochemical study revealed an increased number of unmyelinated Schwann cells in the hyperplastic nerves. We suggest that intraosseous neural hyperplasia is a specific finding of the MEN 2B syndrome in addition to the known oral and facial manifestations.  相似文献   
60.
Gatifloxacine (GFLX)-containing poly(lactide-co-glycolide) (PLGA) was introduced to the pores and surfaces of porous β-tricalcium phosphate (βTCP) granules by melt compounding whereby no toxic solvent was used. The granular composite of GFLX-loaded PLGA and βTCP released GFLX for 42 days in Hanks' balanced solution and exhibited sufficient in vitro bactericidal activity against Streptococcus milleri and Bacteroides fragilis for at least 21 days. For in vivo evaluation, the granular composite was implanted in the dead space created by the debridement of osteomyelitis lesion induced by S. milleri and B. fragilis in rabbit mandible. After a 4-week implantation, the inflammation area within the debrided area was markedly reduced accompanied with osteoconduction and vascularization in half of the rabbits, and even disappeared in one of the six rabbits without any systemic administration of antibiotics. Outside the debrided area, inflammation and sequestrum were observed but the largest of such affected areas amounted to only 0.125 times of the originally infected and debrided area. These findings showed that the granular composite was effective for the local treatment of osteomyelitis as well as an osteoconductive scaffold which supported and encouraged vascularization.  相似文献   
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