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51.
《Journal of orthopaedic research》2017,35(6):1311-1322
52.
Wanting He Gairu Li Henan Zhu Weifeng Shi Ruyi Wang Cheng Zhang Yuhai Bi Alexander Lai George F. Gao Shuo Su 《Transboundary and Emerging Diseases》2019,66(2):842-851
H3N2 canine influenza virus (CIV) originated from avian species and emerged in dogs in Asia around 2005 where it became enzootic before reaching the USA in 2015. To investigate the key aspects of the evolution of H3N2 CIV regarding its emergence and adaptation in the canine host, we conducted an extensive analysis of all publicly available H3N2 CIV sequences spanning a 10‐year period. We believe that H3N2 AIVs transferred to canines around 2002–2004. Furthermore, H3N2 CIVs could be divided into seven major clades with strong geographic clustering and some changed sites evidence of adaptive evolution. Most notably, the dN/dS of each H3N2 CIVs segment was higher than the correspondent of H3N2 AIVs and the U content of HA and NA was increasing over time, suggesting the idea that this avian‐origin virus may be gradually adapting to the host. Our results provide a framework to elucidate a general mechanism for emergence of novel influenza viruses. 相似文献
53.
目的观察急性中央尖的临床症状及治疗的愈后。方法对无症状而牙尖低平的畸形中央尖不予处理或进行调磨;对高而尖而无症状的畸形中央尖进行磨除并制备洞形,进行充填;对有牙髓炎症的畸形中央尖进行活髓切断术或根管治疗。结果早期调磨的畸形中央尖无任何自觉症状,预后好;而波及牙髓的患牙治疗有失败病例。结论临床发现有畸形中央尖的患牙应及早治疗。 相似文献
54.
INTRODUCTION: A heart in fibrillation can be entrained by long-lasting alternating current (AC) stimuli, leading to defibrillation. To investigate the role entrainment plays in defibrillation, computer simulations of AC cardioversion in a three-dimensional slice of the canine heart were performed. METHODS AND RESULTS: A bidomain finite element model of a 1-mm thick slice across the ventricles of a canine heart was used to simulate termination of transmural reentry with AC shocks. Cardioversion defibrillation thresholds (DFTs) were determined for 200-msec (L) AC shocks at varying frequencies. At the DFT, the entire tissue is entrained by the AC shock. DFT decreases as the frequency of the long-lasting AC shock increases. We hypothesize that this decrease is due to the short period of the high-frequency AC waveform, leaving strong virtual electrode polarization (VEP) after the shock ends. To test this hypothesis, the end-shock VEP were compared for different frequencies, demonstrating stronger polarization as frequency increased. To examine whether entrainment by the long-lasting AC shock contributes to the VEP at the end of the shock, additional simulations were conducted using single-period (Z) AC waveforms. Z waveform DFTs were higher than L waveform DFTs; the Z waveform VEP was weaker than the L waveform VEP at the same frequency. This indicates that entrainment contributes to the development of stronger VEP and, thus, to lower DFT at high frequencies. CONCLUSION: This study offers for the first time a mechanistic insight into cardioversion with long-lasting AC shocks. 相似文献
55.
五种中草药提取物及其复方对犬细小病毒的影响 总被引:1,自引:0,他引:1
目的对山茶叶、轮叶党参、卵叶芍药、苦味西葫芦、狼毒大戟5种中草药的提取物进行了体外抗犬细小病毒(CPV)筛选,筛选出抗病毒效果较好的山茶叶,并由山茶叶、黄芪等组成复方,并对该复方进行了抗病毒效果评价与药理作用研究。方法采用体外细胞培养和整体实验。结果研究表明山茶叶抗CPV作用较强,其对CPV的抑制率为55.24%,由山茶叶组成复方对CPV的抑制率为63.04%,抗病毒效果明显优于单方的山茶叶和药物对照黄连,对CPV50%抑制浓度(IC50)为1:587.5。并对大肠杆菌、沙门氏菌、金黄色葡萄球菌有抑制作用,可增强机体免疫力。结论提示本复方有较强抗病毒作用。 相似文献
56.
Stephen L. Silberman DMD DrPH William K. Duncan DDS MSD Aaron Trubman DDS MPH Edward F. Meydrech PhD 《Journal of public health dentistry》1989,49(1):15-18
Primary canine hypoplasia is an incomplete or defective development of the enamel matrix. The lesion is located on the labial surface and is seen more frequently on mandibular teeth. The purpose of this preliminary study was to determine the prevalence of this lesion among Head Start children. During a dental needs assessment of Mississippi Head Start children, 371 children from 11 centers were examined for this lesion. Of the centers, four were located in optimally fluoridated communities, and six were located in fluoride-deficient communities. Ages ranged from three to five years. There were 206 males and 165 females, 334 black and 37 white children. At ten centers all children were black, while all children at one center were white. Results indicated no significant differences in the black population between fluoridated (38.2%) and fluoride-deficient (36.3%) communities (P = .729) or between males (36.8%) and females (37.6%) (P = .877). When data were collapsed on sex and fluoridation status, the racial differences were highly significant (P = .001). The prevalence rate of dental caries associated with primary canine hypoplasia was 26.0 percent. These preliminary data indicate that the presence of primary canine hypoplasia may result in an increased potential for the tooth becoming carious. 相似文献
57.
58.
Pilocarpine-stimulated canine prostatic secretions were subjected to gel filtration chromatography over Sephadex G-100 and Bio Gel P-4. Free zinc and the zinc in pilocarpine-stimulated canine prostatic secretions were observed to elute in the same fractions from the Sephadex G-100 column. In addition, Sephadex G-100 chromatography could not resolve free zinc from the small peptide bacitracin. However, a column packed with Bio Gel P-4 could resolve free zinc and bacitracin. When pilocarpine-stimulated canine prostatic secretions were chromatographed over the Bio Gel P-4 column, the major portion of the zinc eluted in the same fractions as did free zinc. No zinc was observed in the fractions where the small peptide bacitracin was found to elute. These results indicate that contrary to a previous report, zinc in pilocarpine-stimulated canine prostatic secretions was not bound to an eight amino acid peptide, but, rather, behaved chromatographically like free zinc. 相似文献
59.
BACKGROUND AND OBJECTIVES: Low-intensity laser therapy (LILT) has been studied in many fields of dentistry, but to our knowledge, this is the first time that its effects on orthodontic movement velocity in humans are investigated. STUDY DESIGN/PATIENTS AND METHODS: Eleven patients were recruited for this 2-month study. One half of the upper arcade was considered control group (CG) and received mechanical activation of the canine teeth every 30 days. The opposite half received the same mechanical activation and was also irradiated with a diode laser emitting light at 780 nm, during 10 seconds at 20 mW, 5 J/cm2, on 4 days of each month. Data of the biometrical progress of both groups were statistically compared. RESULTS: All patients showed significant higher acceleration of the retraction of canines on the side treated with LILT when compared to the control. CONCLUSIONS: Our findings suggest that LILT does accelerate human teeth movement and could therefore considerably shorten the whole treatment duration. 相似文献
60.
Martin de las Mulas J Ordás J Millán Y Fernández-Soria V Ramón y Cajal S 《Breast cancer research and treatment》2003,80(3):363-367
Immunohistochemical (IHC) HER-2/neu protein overexpression was found in 17.6% of canine mammary gland carcinomas, a percentage similar to that observed in human breast carcinoma, but there was no gene amplification by chromogenic in situ hybridization (CISH). Canine mammary carcinoma would be a suitable natural model of that subset of human breast carcinomas with HER-2 protein overexpression without gene amplification. 相似文献