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51.
ObjectivesIn geriatric acetabular fractures, the quadrilateral surface (QLS) was frequently involved in acetabular fracture patterns and accompanied by medial displacement. It was important to buttress the medial displaced QLS and reconstruct the congruity of the affected acetabulum. To evaluate the clinical effectiveness of the novel infra‐pectineal quadrilateral surface buttress plates for the treatment of geriatric acetabular fractures.MethodsTwenty‐three geriatric patients who were treated for acetabular fractures involving QLS with the novel infra‐pectineal buttress plates (NIBP) through a single supra‐ilioinguinal approach between January 2015 and June 2019 were retrospectively analyzed; all patients received at least 1 year''s follow‐up. All patients were aged ≥60 years old and including 18 males and five females. Radiologic and clinical outcomes of patients involved in the study were collated and analyzed according to the Matta scoring system and the Merle D''Aubigné–Postel scoring system. The functional recovery scoring was compared using q‐test.ResultsAll 23 consecutive patients had relatively satisfactory clinical treatment effectiveness. Average ages, length of incision, operation time, and intraoperative blood loss were 69.8 ± 6.1 years, 12.1 ± 2.6 cm, 166.5 ± 43.5 min, and 500 (500,700) ml, respectively. According to the Matta scoring system, 14 cases of reduction were graded as excellent, five as good, and four as fair. At the last follow‐up, the clinical outcome evaluation was excellent in 13 cases, good in seven cases, and poor in three cases with the use of the Merle D''Aubigné–Postel scoring system. The difference of modified Merle D''Aubigne‐Postel score at 3 months, 6 months and last follow up was statistically significant (F = 21.56, p < 0.05). Postoperative lateral femoral cutaneous nerve injury occurred in three patients and heterotopic ossification occurred in one patient.ConclusionsFor the treatment of geriatric acetabular fractures, the NIBP could provide stable and effective fixation to the QLS involved acetabular fractures, and related satisfactory clinical results with few complications were noted.  相似文献   
52.
三种螺距对种植体初期稳定性影响的有限元研究   总被引:10,自引:2,他引:8  
目的:利用即刻负载有限元模型,研究种植体不同螺纹螺距因素对初期稳定性的影响。方法:利用Pro/E软件、Hypermesh软件及ABAQUS有限元软件,建立四类种植体即刻负载的三维有限元模型,比较3种螺纹螺距(0.8mm、1.6mm、2.4mm)在分别垂直和水平加载时,对种植体初期稳定性的影响。结果:对不同螺纹螺距种植体来说,垂直加载和水平加载时0.8mm螺距螺纹种植体微动最小,2.4mm螺距螺纹种植体微动最大。结论:螺纹的螺距对垂直相对位移有影响,对水平相对位移影响不大。随着螺距的增加,种植体对抗垂直向载荷的抵抗力减弱。水平加载时,螺纹的螺距对颈部微动影响不明显。  相似文献   
53.
BackgroundHepatocellular carcinoma (HCC) is the fifth most common cancer in the world, and more than half of the newly diagnosed cases are chronic hepatitis B patients. Due to the lack of specific clinical manifestations, many patients are already at an advanced stage at the time of diagnosis and therefore have missed the best time for treatment. Organs in a pathological state usually secrete specific substances into the blood, which can indirectly indicate the pathological state of the organ, so some biological markers in the blood can be used as a tool to predict the incidence of HCC.MethodsThe Research articles related to HCC were collected by searching PubMed databases with the keywords “hepatocellular carcinoma”, “serum biomarker”, “hepatitis B”, “prediction” and “prognosis”, and Additional articles were identified by manual search of references found in the primary articles, followed by a summary and review.ResultsViral hepatitis is the main cause of HCC worldwide, and this phenomenon is particularly prominent in Asian and African populations. A variety of serological markers including M2BPGi, IL-6 and COMP can be used to predict the incidence of long-term HCC in patients. The risk of HCC is dynamic rather than constant, and dynamic detection will help improve prediction accuracy. For hepatitis B patients, HBV DNA load and HBcr Ag are important predictive markers of HCC.ConclusionFor a high-risk population of HCC, early risk prediction is helpful to guide clinical work, and timely adjustments of the screening frequency and treatment plan are helpful to prolong the survival time of HCC patients.  相似文献   
54.
Aluminum alloy is widely used in automobile parts because of its light weight and good process performance. In view of the complex structure of aluminum alloy automobile rear upper control arms, multiple forming processes and the difficulty in quality control, in this paper, we propose a rolling-forging composite process to produce a rear upper control arm. Based on the reasonable volume distribution of the blank by cross-wedge rolling, multi-step forging was carried out. Finite element simulation of thermomechanically coupled multi-step forming was carried out using DEFORM software. Based on a comparison of the traditional process and the proposed rolling-forging composite forming process, we concluded that the rolling-forging composite process can greatly reduce the material cost and the forming force, resulting in superior product performance. The coarse-grain structure of products at different process temperatures was analyzed by a crystal-phase experiment. The results show that the process temperature of the multi-step process, as well as the heat treatment temperature and time have an important influence on the coarse-grain structure of the product. The optimal preheating temperatures for preforging and final forging dies were determined to be 335 °C and 350 °C, respectively; a preheating temperature of 530 °C and a solution time of 45 min resulted in the least coarse-grain surface structure. The research results provide a theoretical basis for improving the multi-step forming quality of automobile rear upper control arms.  相似文献   
55.
寡转移性非小细胞肺癌( NSCLC)不同于广泛转移的晚期 NSCLC,针对寡转移灶局部治疗可获得潜在治愈的可能。立体定向放射治疗( SBRT)作为有效的局部治疗手段,联合化疗、络氨酸激酶抑制剂( TKIs)、免疫检查点抑制剂( ICIs)、抗血管生成等可以为晚期 NSCLC病人带来生存获益。该文回顾了 SBRT在寡转移性 NSCLC的研究,从 SBRT对寡转移性 NSCLC的治疗效果、 SBRT联合 TKIs和 SBRT联合 ICIs的临床研究进展展开综述。  相似文献   
56.
五仁液有效成分分析   总被引:4,自引:0,他引:4  
应用GC/MS联用技术研究了五仁液有效成分及其相对含量,发现五仁液中含有丰富的酚类、苯甲酸类、脂肪酸等抗微生物的有效成分。该结果证实了五仁液消毒、杀菌和治疗皮肤病的有效性。  相似文献   
57.
BACKGROUNDLipid metabolism disorder and inflammatory-immune activation are vital triggers in the pathogenesis of nonalcoholic fatty liver disease (NAFLD). Various studies have shown that PPAR-γ exerts potent anti-inflammatory and immunomodulatory properties. However, little is known about the regulation of PPAR-γ activity in modulating cell crosstalk in NAFLD.AIMTo investigate whether the regulation of PPAR-γ activity in lipid-laden hepatocytes affects macrophage polarization and inflammation.METHODSPrimary hepatocytes were isolated from wild-type C57BL6/J mice or hepatocyte-specific PPAR-γ knockout mice and incubated with free fatty acids (FFAs). Macrophages were incubated with conditioned medium (CM) from lipid-laden hepatocytes with or without a PPAR-γ agonist. Wild-type C57BL/6J mice were fed a high-fat (HF) diet and administered rosiglitazone.RESULTSPrimary hepatocytes exhibited significant lipid deposition and increased ROS production after incubation with FFAs. CM from lipid-laden hepatocytes promoted macrophage polarization to the M1 type and activation of the TLR4/NF-κB pathway. A PPAR-γ agonist ameliorated oxidative stress and NLRP3 inflammasome activation in lipid-laden hepatocytes and subsequently prevented M1 macrophage polarization. Hepatocyte-specific PPAR-γ deficiency aggravated oxidative stress and NLRP3 inflammasome activation in lipid-laden hepatocytes, which further promoted M1 macrophage polarization. Rosiglitazone administration improved oxidative stress and NLRP3 inflammasome activation in HF diet-induced NAFLD mice in vivo.CONCLUSIONUpregulation of PPAR-γ activity in hepatocytes alleviated NAFLD by modulating the crosstalk between hepatocytes and macrophages via the reactive oxygen species-NLRP3-IL-1β pathway.  相似文献   
58.
益气化瘀补肾法对退变颈椎间盘Ⅱ型胶原mRNA表达的影响   总被引:11,自引:3,他引:11  
目的益气化瘀补肾法对退变颈椎间盘Ⅱ型胶原mRNA表达的影响。方法健康成年新西兰大白兔42只,随机平均分为益气化瘀补肾组、益气化瘀组、补肾组、消炎组、模型对照组、正常对照组。建立颈椎病椎间盘退变模型,原位杂交后病理图像分析。结果正常对照组髓核组织中Ⅱ型胶原mRNA表达的量显著高于模型对照组和消炎痛治疗组(P<0.01),与益气化瘀组、补肾组相比较也有显著差异(P<0.05);益气化瘀补肾法与益气化瘀法、单纯补肾法比较有较显著差异(P<0.05),与消炎痛组、模型组比较有非常显著差异(P<0.01);益气化瘀法、补肾法对髓核组织中Ⅱ型胶原mRNA的表达有一定的增强作用。结论颈椎病家兔椎间盘的Ⅱ型胶原mRNA表达比正常组显著降低,益气化瘀补肾法可以上调Ⅱ型胶原mRNA基因的表达,使之维持在正常范围,说明益气化瘀补肾法对延缓椎间盘的退变有积极作用。  相似文献   
59.
雄黄诱导肿瘤细胞凋亡的实验研究   总被引:18,自引:0,他引:18  
刘京生  吕占军 《河北中医》2000,22(11):874-876
目的 观察中药雄黄诱导肿瘤细胞凋亡的作用。方法 以细胞凋亡和免疫功能为主要观测指标,观察中药雄黄对荷瘤小鼠的抗肿瘤作用。结果 实验表明,雄黄可诱导荷瘤(L-1210和H22)小鼠的肿瘤组织凋亡,抑制荷瘤小鼠肿瘤的生长,并可延长小鼠存活时间。结论 雄黄可通过诱导肿瘤细胞凋亡,抑制细胞DNA的合成,增强机体的细胞免疫功能等多种因素发挥抗肿瘤作用,显示出广阔的应用前景。  相似文献   
60.
Study Objective: To compare the surgical and oncologic outcomes between abdominal radical trachelectomy (ART) and radical hysterectomy (RH) for stage IA2-IB1 cervical cancer.Design: A retrospective cohort study (Canadian Task Force classification II-2).Setting: Shandong Cancer Hospital, Shandong, China.Patients: Three hundred twenty-nine patients with IA2-IB1 cervical cancer.Interventions: All patients underwent ART or RH.Measurements and Main Results: All patients were divided into ART (n?=?143) and RH (n?=?186) groups according to the surgical approach. Additionally, oncologic and fertility outcomes were compared for different tumor pathologies and sizes in ART patients. The ART group had similar case characteristics as the RH group, except that the ART group had a longer surgical time. During a similar follow-up period, there were 4 (2.9%) recurrences and 3 (2.2%) patients who died from recurrence in the ART group compared with 8 (4.6%) recurrences and 4 (2.3%) patients who died from recurrence in the RH group (p?=?.444 and p?=?.999, respectively). In the ART group, squamous cell carcinoma (SCC) patients had a 5-year overall survival and pregnancy rate similar to those of non-SCC patients (98.1% vs 96.8%, p?=?.999; 33.3% vs 26.7%, p?=?.873), and patients with tumors ≤2 cm and 2 to 4 cm experienced a similar 5-year overall survival rate (97.0% vs 98.6%, p?=?.999), except patients with tumors ≤2 cm had a higher pregnancy rate (45.2% vs 17.2%, p?=?.020).Conclusion: ART seems to have similar surgical and oncologic outcomes to RH, except ART has a longer surgical time. Both non-SCC patients and stage IA2-IB1 patients with 2- to 4-cm tumors can undergo ART safely. Patients with tumors ≤2 cm have a higher pregnancy rate than patients with 2- to 4-cm tumors.  相似文献   
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