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1.
目的总结近年来股骨转子间骨折在稳定性重建方面的概念演化与研究进展。方法查阅国内外相关文献并结合自身经验,从股骨转子间骨折的解剖特点、稳定型骨折与不稳定型骨折分类、稳定性复位与不稳定性复位、术中加压初始稳定与术后滑动二次稳定、内固定术后稳定性评估、早期下地站立负重等方面进行总结分析。结果股骨转子间骨折发生于股骨颈干骺端转换区,具有天然的内翻不稳定倾向。骨折复位质量是影响后续内固定物安放的最重要前提因素。判断骨折复位质量有对线和对位两方面,对线采用 Garden 指数;在对位方面,随着皮质对位理念(正性、中性、负性)的提出,特别强调前内侧皮质的相互砥住支撑(解剖、正性),是获得骨折稳定性复位的关键,而不再强调后内侧小转子骨块的作用。术后影像学的稳定性评分为早期下地站立负重提供了量化指标。但术中的前内侧皮质支撑复位,在术后头颈骨块滑动获得二次稳定的过程中,仍有皮质对位丢失现象,需研究其危险因素和防范措施。结论股骨转子间骨折在取得良好对线的基础上,只要获得了前内侧皮质的相互砥住和支撑,并用内固定器械维持住,就获得了术后稳定性。术后稳定性评分优良者,可以安全地早期下地负重、站立行走活动。  相似文献   
2.
HER2-positive (HER2+) breast cancer (BC) is a heterogenous and multifaceted disease, with interesting therapeutic implications. First, all intrinsic molecular subtypes can be identified in HER2+ tumors, with the HER2-enriched being the most frequent. Such subtypes do not differ much from their counterparts in HER2-negative disease, apart for the high expression of genes in/near the HER2 amplicon on chromosome 17. Intrinsic subtyping, along with the quantification of ERBB2 mRNA levels, is associated with higher rates of pathologic complete response across neoadjuvant trials of dual HER2 blockade and might help select patients for de-escalation and escalation treatment strategies. Secondly, HER2+ tumors have a broad range of DNA alterations. ERBB2 mutations and alterations in the PI3K/Akt/mTOR pathway are among the most frequent and might predict benefit from potent pan-HER, PI3K and mTOR inhibitors. Moreover, HER2+ tumors are usually infiltrated by lymphocytes. These tumor infiltrating-lymphocytes (TILs) predict response to neoadjuvant anti-HER2-based treatment and exert a prognostic role. PD-L1, detected in ∼42 % of HER2+ BC, might also be useful to define patients responding to novel anti-PD1/PD-L1 immunotherapies. New multiparametric clinicopathologic and genomic tools accounting for this complexity, such as HER2DX, are under development to define more tailored treatment approaches. Finally, HER2-targeted antibody-drug conjugates (ADC) such as trastuzumab deruxtecan might be active in tumors with low expression of HER2. Overall, there is a need to molecularly characterize and develop novel targeted therapies for HER2+ disease.  相似文献   
3.
目的 检测蒜氨酸最低抑菌浓度(MIC)与最低杀菌浓度(MBC),探讨蒜氨酸体内外抗菌机制。方法 体外微量稀释法检测蒜氨酸MIC和MBC,荧光显微镜观察菌体表面蒜氨酸,探讨蒜氨酸抗菌机制。体内蒜氨酸和青霉素分别治疗金葡菌感染家兔脓肿,检测脓汁标本中细菌存活情况,探讨体内蒜氨酸抗菌作用。结果 蒜氨酸对大肠杆菌、伤寒杆菌、金黄色葡萄球菌、白色葡萄球菌的MIC分别为3.047 μg·mL-1、6.094 μg·mL-1、0.386 μg·mL-1、0.386 μg·mL-1,蒜氨酸体外无杀菌活性。浓汁标本:死菌率蒜氨酸治疗组显著高于阴性对照组(P < 0.01),与青霉素治疗组无明显差异(P > 0.05);活菌率蒜氨酸治疗组显著低于阴性对照组(P < 0.01),与青霉素治疗组无明显差异(P > 0.05)。结论 蒜氨酸与菌体蛋白、细菌酶蛋白结合阻断细菌与环境物质交换,抑制细菌生命活动,具有较强的抑菌作用,无杀菌活性;蒜氨酸体内代谢成大蒜素,具有较强杀菌作用。  相似文献   
4.
《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   
5.
肺癌是世界上发病率最高的癌症之一,且尚无二线进展后的标准治疗方案,而肿瘤血管生成目前已被确定为恶性肿瘤的重要治疗靶点,小分子多靶点血管激酶抑制剂可通过抑制血管生成相关信号通路,抑制肿瘤血管的生成。目前已开展多项小分子抗血管生成药物治疗非小细胞肺癌的临床试验,且已有部分血管内皮生长因子受体酪氨酸激酶抑制剂(vascular endothelial growth factor receptor-tyrosine kinase inhibitors, VEGFR-TKIs)获批治疗晚期非小细胞肺癌,本文基于国内外多项小分子抗血管生成药物治疗非小细胞肺癌的发展现状,归纳了多个VEGFR-TKIs及成纤维细胞生长因子受体(fibroblast growth factor receptor, FGFR)-TKI单药或联合[包括分别与化疗、表皮生长因子受体(epidermal growth factor receptor, EGFR)-TKIs、免疫治疗、放疗等联合)]治疗非小细胞肺癌的疗效与安全性研究,同时探讨了VEGFR-TKIs可能存在的耐药机制及疗效预测指标等,并对未来抗血管治疗非小细胞肺癌的发展趋势以及存在的潜在问题进行展望,同时为肺癌后续的精准治疗及个体化治疗提供新的思路。  相似文献   
6.

Background

The purpose of this study was to compare the outcomes of trauma patients who were injured in a motor vehicle crash and tested positive for alcohol upon hospital arrival versus those who tested negative.

Methods

Study data came from the US National Trauma Data Bank (2007–2010). Any blood alcohol concentration (BAC) found at or above the legal limit (≥0.08?g/dL) was considered “alcohol positive”, and if no alcohol was identified through testing, the patient was considered “alcohol negative”. Patients’ demographics including age >?=?14, race, gender, drug test results, systolic blood pressure, heart rate, injury severity score (ISS), and Glasgow Coma Scale (GCS) were included in the study. Propensity score and exact pair matching were performed between the groups using baseline characteristics.

Results

From a total of 88,794 patients, 30.9% tested positive and 69.1% tested negative for alcohol. There were significant differences found between the groups regarding age, gender, race, and GCS (all p?<?0.001) as well as a significantly higher in-hospital mortality rate (3.5% vs. 2.7%, p?<?0.001) and median time to patient expiration (4 vs. 3 days, p?<?0.001) in the alcohol negative group. After running both matching scenarios, there was no evidence of a significant difference seen in the rates of in-hospital mortality or the median time to patient expiration between the alcohol groups in either matched comparison.

Conclusion

Patients who tested positive for alcohol following a traumatic motor vehicle crash showed no significant increase in in-hospital mortality or time to expiration when compared to propensity score and exact matched patients who tested negative for alcohol.  相似文献   
7.
Background/objectiveObstructive sleep apnea (OSA) is independently associated with dyslipidemia, a surrogate marker of atherosclerosis. Low-density lipoprotein (LDL)-cholesterol is accepted as a major independent risk factor for cardiovascular disease. However, non-high-density lipoprotein (HDL)-cholesterol is a better marker of atherogenic dyslipidemia and recommended as a target of lipid lowering therapy. We aimed to assess the prevalence of atherogenic dyslipidemia, and relationship between OSA severity and serum LDL-cholesterol and non-HDL cholesterol levels in OSA patients.MethodsWe retrospectively evaluated treatment naïve 2361 subjects admitted to the sleep laboratory of a university hospital for polysomnography. All subjects’ lipid profile including total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, and non-HDL-cholesterol were measured.ResultsOut of 2361 patients (mean age 49.6 ± 11.9 years; 68.9% male, apnea-hypopnea index 36.6 ± 28.4/h), 185 (7.8%) had no OSA and 2176 (92.2%) had OSA. Atherogenic dyslipidemia prevalence was high (57–66%) in OSA patients, and especially increased in severe OSA compared to other groups (p < 0.05). Though total and LDL-cholesterol did not differ between those with and without OSA, non-HDL-cholesterol (p = 0.020), and triglycerides (p = 0.001) were higher and HDL-cholesterol levels (p = 0.018) were lower in OSA patients than non-OSA. Non-HDL-cholesterol was significantly correlated with OSA severity (p < 0.001) and hypoxia parameters (p < 0.01), whereas LDL-cholesterol showed no correlation.ConclusionsAtherogenic dyslipidemia is highly prevalent and non-HDL-cholesterol levels are significantly increased, predominantly in severe OSA patients. Non-HDL-cholesterol but not LDL-cholesterol, is significantly correlated with OSA severity and hypoxia parameters. Therefore, it could be better to use non-HDL-cholesterol, which is a guideline recommended target of lipid therapy, as a marker of atherosclerotic cardiovascular risk in OSA patients.  相似文献   
8.

Background

The ZOE-50 (NCT01165177) and ZOE-70 (NCT01165229) phase 3 clinical trials showed that the adjuvanted recombinant zoster vaccine (RZV) was ≥90% efficacious in preventing herpes zoster in adults. Here we present a comprehensive overview of the safety data from these studies.

Methods

Adults aged ≥50 (ZOE-50) and ≥70 (ZOE-70) years were randomly vaccinated with RZV or placebo. Safety analyses were performed on the pooled total vaccinated cohort, consisting of participants receiving at least one dose of RZV or placebo. Solicited and unsolicited adverse events (AEs) were collected for 7 and 30?days after each vaccination, respectively. Serious AEs (SAEs) were collected from the first vaccination until 12?months post-last dose. Fatal AEs, vaccination-related SAEs, and potential immune-mediated diseases (pIMDs) were collected during the entire study period.

Results

Safety was evaluated in 14,645 RZV and 14,660 placebo recipients. More RZV than placebo recipients reported unsolicited AEs (50.5% versus 32.0%); the difference was driven by transient injection site and solicited systemic reactions that were generally seen in the first week post-vaccination. The occurrence of overall SAEs (RZV: 10.1%; Placebo: 10.4%), fatal AEs (RZV: 4.3%; Placebo: 4.6%), and pIMDs (RZV: 1.2%; Placebo: 1.4%) was balanced between groups. The occurrence of possible exacerbations of pIMDs was rare and similar between groups. Overall, except for the expected local and systemic symptoms, the safety results were comparable between the RZV and Placebo groups irrespective of participant age, gender, or race.

Conclusions

No safety concerns arose, supporting the favorable benefit-risk profile of RZV.  相似文献   
9.
PurposeTo investigate dynamic variables obtained from retrospective computed tomography angiography for ability to predict thoracic endovascular aortic repair (TEVAR) outcomes in patients with complicated type B aortic dissection (cTBAD).Materials and MethodsSeventy-nine patients with cTBAD who received TEVAR from March 2009 to June 2018 were retrospectively enrolled. Relative true lumen area (r-TLA) was computed at the level of tracheal bifurcation every 5% of all R-R intervals. Parameters that reflect the state of intimal motion were evaluated, including difference between maximum and minimum r-TLA (D-TLA) and true lumen collapse. The endpoints comprised early (≤ 30 days) and late (> 30 days) outcomes after intervention.ResultsOverall early mortality rate was 13.9% (11/79), and early adverse events rate was 24.1% (19/79). Patients who received TEVAR within 2 days of symptom onset demonstrated the worst outcomes. A longer time of r-TLA < 25% in 1 cardiac cycle (P = .049) and larger D-TLA (P < .001) were correlated to an increased early death. In addition, D-TLA was an independent predictor of early mortality. Area under the curve of D-TLA was 0.849 (95% confidence interval 0.730–0.967) for predicting early mortality and 0.742 (95% CI 0.611–0.873) for predicting early adverse events. Survival and event-free survival rates during follow-up were decreased in the D-TLA > 21.5% group compared with the D-TLA ≤ 21.5% group (all P < .001).ConclusionsLarger D-TLA is correlated with worse postoperative outcomes and might be a crucial parameter for future risk stratification in patients with cTBAD.  相似文献   
10.
目的:评定LC-MS/MS法测定人血浆中布康唑浓度的不确定度。方法:分析测定过程中不确定度的来源,包括对照品的称量、仪器误差、标准溶液的配制、含药血浆样品的配制、血浆样品的处理、标准曲线的拟合、基质效应、重复性等,评定各来源分量的不确定度,计算合成不确定度和扩展不确定度。结果:人血浆中低(60.0 pg·mL-1)、中(600.0 pg·mL-1)、高(6 400.0 pg·mL-1)浓度布康唑的扩展不确定度分别为5.62,63.90,626.26 pg·mL-1k=2,P=95%)。结论:LC-MS/MS法测定人血浆中布康唑浓度的不确定度主要由基质效应、血浆样品的处理(提取回收率),仪器误差、重复性(精密度)引入。  相似文献   
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