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101.
聚合酶链反应诊断单纯疱疹病毒性脑炎 总被引:5,自引:0,他引:5
用聚合酶链反应(PCR)扩增患者脑脊液(ChF)中病毒特异性DNA可早期快速诊断单纯疱疹病毒性脑炎(HSE)。19例临床确诊的病毒性脑炎患者,经PCR在CSF中检出单纯疱疹病毒(HSV)13例,全部阳性标本均经分子杂交证实为HSV-DNA,而14例其他神经疾病(OND)对照组均为阴性,显示了这一方法的特异性。其中7例病毒性脑炎CSF标本分别用PCR分子杂交和病毒分离等三种方法检测HSV;显示PCR最为敏感。表明PCR技术的广泛应用将提高HSE的早期诊断水平,指导临床正确治疗。 相似文献
102.
本文总结了14例应用刮治和自体骨移植术治疗大型牙源性角化囊肿的方法,14例植骨均成活,4例术后囊肿复发,再次手术,指出:与骨断切除治疗大型角化囊肿的方法比较,此法最大的优点是有利于保持患者面容和咀嚼功能,并对大型角化囊肿的手术原则,自体骨移植问题及手术注意事项进行了讨论。 相似文献
103.
Abstract We previously demonstrated that epidermal growth factor (EGF) induces a several-fold increase in ornithine decarboxylase (ODC) activity and the steady-state level of ODC mRNA in cultured SV40-transformed human keratinocytes (1). Pretreatment of cell cultures with ultraviolet B (UVB) radiation resulted in a reduction of EGF-induced ODC activity. To determine whether UVB inhibits the accumulation of ODC mRNA by EGF, cells were pretreated with 20 mJ/cm2 UVB or sham-irradiated and then incubated with 100 ng/ml EGF. Northern blot analysis revealed that UVB irradiation entirely blocked the EGF induction of ODC mRNA. Since the binding of EGF to its plasma membrane receptor is the first step in initiating a biological response, the effect of UVB on EGF binding was evaluated. UVB treatment of cultured keratinocytes resulted in an immediate and dose-dependent reduction of EGF binding. Scatchard analysis revealed thai the reduction of EGF binding was due to a 52% decrease in the number of available receptors, from 6.2 × 104/cell to 3.0 × 104/cell. However, UVB decreased the EGF-binding affinity very little (Kd = 0.60 nM in control and Kd=0.75 nM in UVB-treated Z114 cells). In addition, UVB did not alter the rate of EGF internalization. These data suggest that UVB blocks the signal transduction pathway of EGF that is involved in regulation of ODC gene expression. Immunoblot analysis of extracts from irradiated cells showed that UVB induced tyro-sine phosphorylation of EGFR and that the quantity of EGFR protein was unaffected by UVB treatment. Phosphorylation of EGFR may be responsible for decreased binding of EGF to its receptor. 相似文献
104.
主动脉瓣机械瓣置换术后交替脉 总被引:1,自引:0,他引:1
报道4例因主动脉瓣关闭不全行主动脉瓣置换术后的患者在术后早期出现脉搏交替现象,此时心电图为整齐的窦性心律,所记录的脉搏图形高低交替,如扪诊桡动脉时则会发现桡动脉搏数为心电图示心率的一半。患者术后均顺利恢复,显示这一现象为一过性的、良性的过程。推测这一现象出现的原因可能是术后早期主动脉瓣不再有回流,因而巨大的左室腔充盈不足,加之左室收缩力尚低,不能在每次收缩时都能射出同等量的血流所致 相似文献
105.
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107.
A framework for coronary vessels analysis in digital subtracted angiograms is described. This method combines the motion estimation with the frame-to-frame structure detection in a natural way such that they act interactively. The first step consists of the extraction of the vessel centrelines in one image and their organization into meaningful constituents or branches of the coronary arterial tree. The motion is then estimated along the centrelines through a gradient based method. These motion estimates supply an initial positioning of an active contour model (or snake) in the next image. This model adapts itself by changing its shape to accurately fit onto the new centrelines. This process is then reiterated on the subsequent images to depict the dynamic behaviour of all the relevant branches. The main interests of this scheme are: (1) the active models operate locally so a fast detection of the vessels can be performed; (2) the centrelines extraction is fully guided by the confluence of the motion estimation and the contour model; (3) both morphological and kinetic features are provided on a quantitative basis. 相似文献
108.
A randomized comparison of pre-and post-experimental design was used to examine the effects of a fall prevention exercise program (FPEP) on muscle strength, ankle flexibility, balance, instrumental activities of daily living (IADLs), and depression for the community-dwelling elderly in Korea. Twenty-two subjects were assigned to an experimental group and twenty-three to a control group. The experimental group participated in a 4-day-per week FPEP of 8 weeks duration, twice a week by direct instruction and twice a week with videotaped instruction by the program instructor at each senior center. The eight-week FPEP turned out to be significantly effective in enhancing muscle strength, ankle flexibility and balance, and in reducing depression, after intervention among community-dwelling elderly in Korea. IADLs, however, was not changed by the intervention. Further research with a larger sample and longer follow up period is needed to expand our understanding about the effects of FPEP. Future study is also recommended to differentiate between the effects of FPEP by direct instruction and by videotaped. 相似文献
109.
110.
Wang H Gordon D Olszewski B Song YL Kovesdi I Keiser JA 《International journal of molecular medicine》2000,6(6):645-653
Therapeutic angiogenesis, either by protein injection or gene therapy, holds considerable promise for the treatment of coronary and peripheral artery diseases. Given the large number of angiogenic genes available, a simple, well defined, standard system to compare the relative angiogenic efficacy of such genes would be valuable. We have employed a replication-deficient adenovirus vector (complete E1a-, partial E1b- and partial E3-) to deliver the beta-galactosidase (beta-gal, AdLacZ) reporter gene or the human VEGF121 gene (AdGV VEGF121.10) to a rat sponge implant model of angiogenesis. beta-gal staining results reveal a transfection efficiency as high as 60% 24 h after 2x1010 particle units AdLacZ injection. Our results also indicate that a single injection of 2x1010 particle units of AdGVVEGF121.10 in the sponge results in >10, 000 pg VEGF protein expression per milligram of sponge tissue 24 h later. VEGF121 protein concentrations decreased 10-fold within 3 days and 100-fold within 7 days after injection. Significant VEGF121 protein levels were still detectable 14 days after initial virus injection. The high level of gene transfection efficiency was accompanied by enhanced angiogenesis in the sponge, a tissue devoid of any vessels before implantation. Compared to control (AdNull: adenovirus vector without the VEGF gene), AdGVVEGF121.10 induced a 2- to 3-fold up-regulation of angiogenesis at 7 and 14 days post vector injection as determined by both increased capillary number and increased tissue ingrowth. The angiogenic effects of AdGVVEGF121. 10 were dose-related in this model system. These findings demonstrate a dose-related angiogenic response to adenovirus-mediated gene therapy in this model. 相似文献