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71.
《International journal of oral and maxillofacial surgery》2020,49(4):466-470
The purpose was to assess maxillary position among patients undergoing Le Fort I maxillary advancement with internal fixation placed only at the nasomaxillary buttresses. This was a retrospective study of patients undergoing a Le Fort I osteotomy for maxillary advancement, with internal fixation placed only at the nasomaxillary buttresses. Demographic and cephalometric measures were recorded. The outcome of interest was the change in maxillary position between immediately postoperative (T1), 6 weeks postoperative (T2), and 1 year postoperative (T3). Fifty-eight patients were included as study subjects (32 male, 26 female; mean age 18.4 ± 1.8 years). Twenty-five subjects (43.1%) had a diagnosis of cleft lip and palate. Forty-three subjects (74.1%) had bimaxillary surgery, 16 (27.6%) had bone grafts, and 18 (31.0%) had segmental maxillary osteotomies. At T3, there were no subjects with non-union, malunion, malocclusion, or relapse requiring repeat surgery. Mean linear changes between T1 and T3 were ≤1 mm. Mean angular changes between T1 and T3 were <1°. There was no significant difference in stability in multi-segment maxillary osteotomies (P = 0.22) or with bone grafting (P = 0.31). In conclusion, anterior fixation alone in the Le Fort I osteotomy results in a stable maxillary position at 1 year postoperative. 相似文献
72.
《Journal of cranio-maxillo-facial surgery》2020,48(7):645-652
PurposeThis study compared piezoelectric (PE) and conventional drills (CD) for maxillary aesthetic zone implant insertion.Material and methodsThis was a prospective split-mouth study. Implants were divided into two groups. Beds were prepared with CDs in group I and PE in group II. The implant stability quotient (ISQ) of the mechanical implant stability (MIS) was measured intraoperatively. The ISQ of the biological implant stability (BIS) was recorded at postoperative second and fourth months. Marginal bone loss (MBL) and bone density (BMD) were measured in the first and second years after prosthetic loading. The osteotomy time was also documented for both techniques. P values <0.05 were considered significant.ResultsSixty implants in 30 patients were included. PE provided a significantly higher ISQ. All values were above 70 throughout the follow-up period. The mean of the ISQ for MIS was 63.78 ± 1.03 and 73.89 ± 1.05 in group I and group II, respectively (p = 0.003). PE needed significantly longer osteotomy time with a mean of 11.99 ± 0.839 min. The BIS quality had high stability in group II and medium stability in group I throughout the study period. Its values decreased in both groups. Group II had a lesser percentage of decrease. However, it was significant only at time intervals between intraoperative and two months' postoperative (p = 0.004). MBL and BMD demonstrated insignificant results.ConclusionThe implant site preparation with PE devices should be preferred to CDs whenever possible, because they seem to enhance implant stability and osseointegration, especially at the initial stages of healing. 相似文献
73.
《Vaccine》2021,39(45):6601-6613
AKS-452 is a biologically-engineered vaccine comprising an Fc fusion protein of the SARS-CoV-2 viral spike protein receptor binding domain antigen (Ag) and human IgG1 Fc (SP/RBD-Fc) in clinical development for the induction and augmentation of neutralizing IgG titers against SARS-CoV-2 viral infection to address the COVID-19 pandemic. The Fc moiety is designed to enhance immunogenicity by increasing uptake via Fc-receptors (FcγR) on Ag-presenting cells (APCs) and prolonging exposure due to neonatal Fc receptor (FcRn) recycling. AKS-452 induced approximately 20-fold greater neutralizing IgG titers in mice relative to those induced by SP/RBD without the Fc moiety and induced comparable long-term neutralizing titers with a single dose vs. two doses. To further enhance immunogenicity, AKS-452 was evaluated in formulations containing a panel of adjuvants in which the water-in-oil adjuvant, Montanide™ ISA 720, enhanced neutralizing IgG titers by approximately 7-fold after one and two doses in mice, including the neutralization of live SARS-CoV-2 virus infection of VERO-E6 cells. Furthermore, ISA 720-adjuvanted AKS-452 was immunogenic in rabbits and non-human primates (NHPs) and protected from infection and clinical symptoms with live SARS-CoV-2 virus in NHPs (USA-WA1/2020 viral strain) and the K18 human ACE2-trangenic (K18-huACE2-Tg) mouse (South African B.1.351 viral variant). These preclinical studies support the initiation of Phase I clinical studies with adjuvanted AKS-452 with the expectation that this room-temperature stable, Fc-fusion subunit vaccine can be rapidly and inexpensively manufactured to provide billions of doses per year especially in regions where the cold-chain is difficult to maintain. 相似文献
74.
《Vaccine》2021,39(13):1870-1876
Mumps is a contagious disease caused by the mumps virus. It can be prevented using mumps vaccines, administered as a measles-mumps-rubella (MMR) vaccine. For first and second dose immunization, children aged 12–15 months and 4–6 years have been administered this vaccine since 1997 in Korea. Nevertheless, mumps outbreaks still occur in vaccinated populations worldwide. Hence, immunity against these diseases may be attenuated, or there are antigenic differences between currently available vaccine strains and circulating wild-type viruses. After the introduction of national immunization programs in Korea, mumps cases became sporadic. Viral genotypes F, H, and I have emerged since 1998 whereas the vaccine strains belong to genotype A. Here, we compared the amino acid sequences of the haemagglutinin-neuraminidase (HN) gene from wild-type viruses and the mumps vaccine and measured the cross-neutralization titers between them. We selected the F, H, and I wild-type mumps strains circulating in Korea from 1998 to 2016 and analyzed changes in the amino acid sequence of the protein encoded by the HN gene. We measured mumps virus-specific IgG and rapid focus reduction neutralization test (FRNT) titers in Korean isolates and sera obtained from 50 children aged 1–2 years who had been administered a single dose of MMR vaccine. Analysis of the HN protein sequences disclosed no changes in the glycosylation sites but did reveal 4–5 differences between the Korean isolates and the genotype A vaccine strain in terms of the neutralizing epitope sites on their HN proteins. Post-vaccination FRNT titers were significantly lower against genotypes F, H, and I than they were against genotype A. This finding highlights the possibility of a recurrence of mumps outbreaks in vaccinated populations depending on the degree of genetic conservation of the HN gene. Further research into this issue is needed to prevent the resurgence of mumps. 相似文献
75.
目的探讨CEA、CA199、CA724、CA50、CA242、VEGF联合检测在食管胃交界部腺癌患者预后中的应用价值,为临床提供合理的检验指标。方法选取2014年11月至2017年10月安阳市肿瘤医院食管胃交界部腺癌住院患者213例,30例健康体检者作对照。检测其血清中CEA、CA199、CA724、CA50、CA242、VEGF的水平,统计学分析其与预后的关系。结果食管胃交界腺癌组的CEA、CA199、CA724、CA50、CA242、VEGF的水平均高于正常对照组,差异有统计学意义;CEA、CA199、CA724的阴性组患者3年生存率高于阳性组患者(P<0.05);CEA、CA199、CA724、CA50、CA242、VEGF在Ⅰ、Ⅱ、Ⅲ期患者中的阳性率无统计学意义;神经侵犯、CEA阳性、CA724阳性是食管胃交界部腺癌患者预后差的独立危险因素。结论CEA、CA724在评价食管胃交界部腺癌预后方面有良好的应用价值。 相似文献
76.
《Gait & posture》2021
BackgroundImpaired movement stability is a common symptom of Parkinson’s disease (PD) that leads to falls and mishandled objects. Decline in synergistic stabilization of movement in PD patients has been observed in manual and postural tasks. However, locomotor synergies have not been quantified in PD patients.Research questionThe purpose of this work was to quantify the strength of the synergy stabilizing the step length while crossing an obstacle in PD patients. We hypothesized that (1) the distances of the front and rear feet relative to the obstacle would display compensatory across-trial co-variance that stabilizes step length in PD patients and age-matched controls, and (2) the step-length stabilization would be weaker in PD patients.MethodsThirteen PD patients and eleven healthy age-matched controls walked up to and stepped over a 15 cm high obstacle fifteen times.We measured the distances of the rear and front foot toes from the obstacle during the crossing step. We used the uncontrolled manifold method to parse the across-trial variance in toe distances into a component that maintains the step length and a component that changes the step length. These variance components yielded the synergy index that quantified the stability of step length.ResultsStep length was stabilized in PD patients as well as controls. However, the synergy index was 53% lower in the PD patients (p < 0.01). Thus, both our hypotheses were supported.SignificanceThis is the first study reporting impaired locomotor synergies in PD patients. Most PD patients in our sample were early stage (10 out of 13 patients were Hoehn-Yahr ≤ 2). Therefore, this result motivates further studies to establish step-length synergy during adaptive locomotor tasks as a biomarker for early detection of locomotor impairments in PD patients. 相似文献
77.
78.
目的:探索Ⅲ~Ⅳ期糖尿病肾病(DN)患者血清差异蛋白,同时筛选不同中医证型的血清差异蛋白。方法:收集Ⅲ~Ⅳ期DN患者70例(气阴两虚证19例,脾肾气虚证18例,血瘀证16例,湿热证17例),同时选择健康受试者35例(健康对照组),应用表面加强激光解吸电离-飞行时间-质谱(SELDI-TOF-MS)技术检测各组血清蛋白指纹图谱,并对差异蛋白峰进行对比分析。结果:1) DN组与健康对照组之间共有9个蛋白峰存在显著差异,质荷比(M/Z)分别为2042.57、3291.28、4986.15、5312.69、5564.09、9861.47、10786.53、13392.89、17395.27;2)气阴两虚证与脾肾气虚证之间共有4个蛋白峰存在显著差异,M/Z分别为2994.77、4986.15、7937.25、2758.91;3)气阴两虚证与血瘀证之间共有4个蛋白峰存在显著差异,M/Z分别为4986.15、16982.62、6819.69、9947.36;4)气阴两虚证与湿热证之间共有3个蛋白峰存在显著差异,M/Z分别为4986.15、11741.33、7001.54;5)脾肾气虚证与血瘀证之间共有3个蛋白峰存在显著差异,M/Z分别为3448.22、8063.43、9787.21;6)脾肾气虚证与湿热证之间共有5个蛋白峰存在显著差异,M/Z分别为2144.34、3992.01、8871.35、10568.32、14643.47;7)血瘀证与湿热证之间共有6个蛋白峰存在显著差异,M/Z分别为4233.15、5771.32、5987.18、8496.76、6651.25、13551.94。结论:Ⅲ~Ⅳ期DN组与健康对照组血清蛋白表达存在差异,该差异或可作为相关临床诊断的标志物,对探索DN的发病机制具有重要的参考价值;在不同中医证型之间能够找到差异血清蛋白,可能反映"证"的实质内涵,对今后建立诊断决策模型具有积极意义。 相似文献
79.
目的了解长春西部地区过敏原特异性IgE分布情况。方法应用免疫印迹法检测1 258例患者的19种吸入性及食物性过敏原特异性IgE抗体,统计过敏原结果及种类。结果 1 258例患者,检出至少一种特异性IgE阳性率为34.0%。男性阳性率为33.5%;女性阳性率为34.5%。男女间阳性率差异无统计学意义(P> 0.05)。吸入性过敏原阳性率由高到低依次为:普通豚草14.2%、艾蒿11.4%、屋尘螨/粉尘螨8.1%、猫毛3.8%、狗上皮2.4%、柳树/杨树/榆树2.1%,屋尘1.6%、蟑螂1.6%、点青霉/分枝孢霉/烟曲霉/交链孢霉1.2%、葎草1.1%。食物性过敏原阳性率由高到低依次为:鸡蛋白2.9%、鳕鱼/龙虾/扇贝2.7%、牛奶2.3%、黄豆1.9%、蟹1.5%、虾1.3%、牛肉1.2%、花生1.0%、羊肉0.8%。混合过敏达到了相当高的比例。结论长春西部地区吸入性过敏原以普通豚草、艾蒿和屋尘螨/粉尘螨为主;食物性过敏原以鸡蛋白、鳕鱼/龙虾/扇贝、牛奶为主,明确过敏原,对过敏性患者的预防和治疗有重大意义。 相似文献
80.