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51.
To investigate the role of the Toll-like receptor (TLR) family in host defense against Toxoplasma gondii, we infected TLR2-, TLR4- and MyD88-deficient mice with the avirulent cyst-forming Fukaya strain of T. gondii. All TLR2- and MyD88-deficient mice died within 8 days, whereas all TLR4-deficient and wild-type mice survived after i.p. infection with a high dose of T. gondii. Peritoneal macrophages from T. gondii-infected TLR2- and MyD88-deficient mice did not produce any detectable levels of NO. T. gondii loads in the brain tissues of TLR2- and MyD88-deficient mice were higher than in those of TLR4-deficient and wild-type mice. Furthermore, high levels of IFN-gamma and IL-12 were produced in peritoneal exudate cells (PEC) of TLR4-deficient and wild-type mice after infection, but low levels of cytokines were produced in PEC of TLR2- and MyD88-deficient mice. On the other hand, high levels of IL-4 and IL-10 were produced in PEC of TLR2- and MyD88-deficient mice after infection, but low levels of cytokines were produced in PEC of TLR4-deficient and wild-type mice. The most remarkable histological changes with infiltration of inflammatory cells were observed in lungs of TLR2-deficient mice infected with T. gondii, where severe interstitial pneumonia occurred and abundant T. gondii were found.  相似文献   
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The influence of ghrelin on feeding behaviour during infancy is unknown. To determine whether ghrelin influences milk intake in rat pups, newborn rats received a single i.p. injection of either rat ghrelin (100 μg/kg) or rabbit anti-ghrelin immunoglobulin G (100 μg/kg) every 5 days from postpartum day 5 to day 30 (P5–P30). Milk intake was then assessed by body weight gain following a 2-h suckling period. Ghrelin significantly increased weight gain relative to vehicle-injected controls in P20, P25 and P30 pups, but not in younger animals. Similarly, after 8 h of milk restriction, anti-ghrelin injections significantly decreased weight gain in P25 and P30, but not in younger pups. Interestingly, however, ghrelin did increase independent feeding in P10 and P15 pups using a paradigm in which pups consumed milk from a milk-soaked paper towel. We therefore conclude that ghrelin stimulates milk intake at an early postnatal stage, primarily by affecting adult-type feeding behaviour.  相似文献   
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目的 了解我院神经外科介入治疗病人的院内感染现况,分析感染相关的危险因素,为控制神经介入治疗后院内感染与制定预防措施提供参考。方法 回顾性分析2016年1~12月我院神经外科介入治疗的1274例病人的临床资料,统计院内感染率,并对引发院内感染的相关因素进行统计学分析。结果 神经外科介入治疗后院内感染率为2.47%,感染类型主要为呼吸系统感染(72.5%),其次为血液系统感染(15.0%)、泌尿系统感染(7.5%)、中枢神经系统感染(5.0%)。多因素logistic回归分析显示低白蛋白血症、低钾血症、术后输血、留置静脉置管是神经外科介入治疗后院内感染的独立危险因素(P<0.05)。结论 多种因素与神经外科介入治疗院内感染密切相关,应进行针对性地预防,从而达到减少院内感染的目的  相似文献   
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Bilateral frontoparietal polymicrogyria is an autosomal recessive inherited human brain malformation with abnormal cortical lamination. The affected cortex appears to consist of numerous small gyri, with scalloping of the cortical-white matter junction. There are associated white matter, brain stem, and cerebellar changes. Affected individuals manifest mental retardation, language impairment, motor developmental delay, and seizure disorder. GPR56 is the causative gene. Here we report a novel missense mutation of GPR56, E496K, identified in a consanguineous pedigree with bilateral frontoparietal polymicrogyria. GPR56 protein is cleaved at the G-protein-coupled receptor proteolytic site into an N- and a C-terminal fragment, named GPR56N and GPR56C, respectively. E496K is located in GPR56C. Further biochemical studies reveal that this mutation affects GPR56C cell surface expression similar to the effect of a previously reported mutation, R565W. These results provide further insights into how GPR56 mutation causes neurologic disease.  相似文献   
56.
目的总结以过度运动发作为主要表现的药物难治性癫的诊疗经验。方法回顾性分析25例药物难治性癫病人的临床资料,均以过度运动发作为主要表现。根据症状特点、MRI、头皮视频脑电图及颅内脑电图监测,综合定位致灶,并行手术切除。结果切除额叶致灶23例,切除前颞叶致灶2例。神经病理学检查显示:皮质发育不良(FCD)Ⅰ型8例,FCDⅡ型12例,节细胞胶质瘤1例,皮质微发育不良1例,灰质异位1例,胶质瘢痕1例,海马硬化1例。术后随访12~60个月,按Engel分级:Ⅰ级19例,Ⅱ级2例,Ⅲ级2例,Ⅳ级2例。结论以过度运动发作为特点的难治性癫病人,其致灶主要位于额叶,但也可位于额叶外的脑区,准确切除致灶后疗效满意。  相似文献   
57.
OBJECTIVE: To identify global research trends in the use of nerve conduits for peripheral nerve injury repair. DATA RETRIEVAL: Numerous basic and clinical studies on nerve conduits for peripheral nerve injury repair were performed between 2002-2011. We performed a bibliometric analysis of the institutions, authors, and hot topics in the field, from the Web of Science, using the key words peripheral nerve and conduit or tube. SELECTION CRITERIA: Inclusion criteria: peer-reviewed published articles on nerve conduits for peripheral nerve injury repair, indexed in the Web of Science; original research articles, reviews, meeting abstracts, proceedings papers, book chapters, editorial material, and news items. Exclusion criteria: articles requiring manual searching or telephone access; documents not published in the public domain; and several corrected papers. MAIN OUTCOME MEASURES: (a) Annual publication output; (b) publication type; (c) publication by research field; (d) publication by journal; (e) publication by funding agency; (f) publication by author; (g) publication by country and institution; (h) publications by institution in China; (i) most-cited papers. RESULTS: A total of 793 publications on the use of nerve conduits for peripheral nerve injury repair were retrieved from the Web of Science between 2002-2011. The number of publications gradually increased over the 10-year study period. Articles constituted the main type of publication. The most prolific journals were Biomaterials, Microsurgery, and Journal of Biomedical Materials Research Part A. The National Natural Science Foundation of China supported 27 papers, more than any other funding agency. Of the 793 publications, almost half came from American and Chinese authors and institutions. CONCLUSION: Nerve conduits have been studied extensively for peripheral nerve regeneration; however, many problems remain in this field, which are difficult for researchers to reach a consensus.  相似文献   
58.
Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system. Exogenous cell replacement in MS lesions has been proposed as a means of achieving remyelination when endogenous remyelination has failed. However, the ability of exogenous cells to remyelinate axons in the presence of inflammation remains uncertain. We have explored the remyelinating capacity of an oligodendrocyte progenitor cell line CG-4 transduced with the GFP gene and transplanted adjacent to a zymosan-induced focal demyelination model in the rat spinal cord. The resulting zymosan-induced lesions were characterized by persistent macrophage/microglia activation, focal demyelination, degeneration of axons, and reactive astrogliosis. GFP(+) CG-4 cells were found to migrate preferentially toward the inflammatory lesion and survive inside the lesion. A proportion of GFP(+) CG-4 cells differentiated into mature oligodendrocytes and remyelinated axons within the lesion. These findings suggest that grafted oligodendrocyte progenitors may migrate toward areas of inflammation in the adult rat spinal cord, where they can survive and differentiate into myelinating oligodendrocytes.  相似文献   
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目的 研究多层(16层)螺旋CT(multi slice spiral CT,MSCT)冠状动脉造影成像在评价冠状动脉支架通畅性的临床意义,并分析影响其成像质量的因素.方法 采用MSCT对32例冠状动脉支架患者行冠状动脉成像检查,以多种方式重建显示冠状动脉支架的位置、形态、术后再狭窄等.其中7例经X线冠状动脉造影进一步证实.将CT冠状动脉图像质量分三级予以评价,分析其影响图像质量的因素.结果 MSCT显示所有32例患者41个冠状动脉支架的形态、位置,其中5个支架术后出现再狭窄;7例患者9个支架与冠状动脉造影对照,诊断符合率为88.9%;图像质量优良率为87.5%(28/32例),心率<60/min、61~70/min和>71次/min图像质量优良率分别占94.7%、88.9%和50.0%,三种不同心率对图像质量显示有显著性差异(χ2=16.354,P<0.01).结论 MSCT冠状动脉成像是一种较可靠的冠状动脉支架无创性评价方法,对支架开通性显示较好,但对支架内情况显示受限,图像质量受心率等因素影响,质量控制是关键.  相似文献   
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