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991.
Haleh Tajadodi Aziz Khan Jos Francisco Gmez‐Aguilar Hasib Khan 《Optimal control applications & methods.》2021,42(1):96-109
In this paper, we study fractional‐order optimal control problems (FOCPs) involving the Atangana‐Baleanu fractional derivative. A computational method based on B‐spline polynomials and their operational matrix of Atangana‐Baleanu fractional integration is proposed for the numerical solution of this class of problems. With this numerical technique, the FOCPs are reduced to a system of equations which are solved for the unknown parameters with the help of Mathematica® software. Our results show the applicability and usefulness of the numerical technique. 相似文献
992.
The relationships between cancer caused by HPV and some vitamins, as well as leucocytes and their ratios, have been investigated in the literature. Our aim is to evaluate these relationships at the level of genital wart in terms of the investigated parameters and lesion numbers. Data were obtained from 98 and 94 patients for groups one and two, including warts patients and healthy people respectively. The Neutrophil/Monocyte ratio and lesion numbers in the warts patients were reported and analysed in terms of vitamin B12 and D, ferritin and leucocytes. A correlation was established between lesion numbers, age and midcorpuscular volume (p <0.05). There was no correlation between lesion numbers and recurrence. According to the comparative analysis, there were differences in terms of ferritin, neutrophil, monocyte, haemoglobin, midcorpuscular volume and neutrophil/monocyte ratio between groups. The cut-off values for neutrophil, monocyte and N/M ratios were 56.45, 4.91 and 7.825 respectively. While our study showed that wart development may be affected by blood ferritin levels and in this situation, midcorpuscular volume, neutrophil, monocyte and N/M ratios may change, a relation was found between lesion numbers and age and mean midcorpsucular volume values only. However, further studies are needed to clarify this issue. 相似文献
993.
Polyorchidism is usually diagnosed incidentally when the patient undergoes imaging or surgery for some other reason. Although we are facing lack of evidence in different steps of diagnostic and therapeutic workup of these patients, this disorder is usually considered benign, not requiring any intervention. We report the case of a man complaining of a palpable mass in his scrotum. We evaluated the patient using ultrasound, MRI and serum tumour marker level measurement. The patient was finally diagnosed with polyorchidism (three testes). For the management, we recommended annual physical examination, US examination and serum tumour marker level measurement. 相似文献
994.
Luca M. Sconfienza Domenico Albano Carmelo Messina Rocco D’Apolito Elena De Vecchi Luigi Zagra 《The Journal of arthroplasty》2021,36(8):2962-2967
BackgroundTo diagnose periprosthetic joint infection (PJI) preoperatively, ultrasound-guided joint aspiration (US-JA) may not be performed when effusion is minimal or absent. We aimed to report and investigate the diagnostic performance of ultrasound-guided periprosthetic biopsy (US-PB) of synovial tissue to obtain joint samples in patients without fluid around the implants.MethodsOne-hundred nine patients (55 men; mean age: 68 ± 13 years) with failed total hip arthroplasty (THA) who underwent revision surgery performed preoperative US-JA or US-PB to rule out PJI.ResultsSixty-nine of 109 patients had joint effusion and underwent US-JA, while the remaining 40 with dry joint required US-PB. Thirty-five of 109 patients (32.1%) had PJI, while 74/109 (67.9%) had aseptic THA failure. No immediate complications were observed in both groups. Technical success of US-PB was 100%, as the procedure was carried on as planned in all cases. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of US-JA were 52.2%, 97.8%, 92.3%, 80.3%, and 82.6%, while for US-PB, they were 41.7%, 100%, 100%, 80%, and 82.5%, respectively, with no significant difference (P = .779). Using the final diagnosis as reference standard, we observed a moderate agreement with both US-JA (k = 0.56) and US-PB (k = 0.50).ConclusionWe present a novel US-guided technique to biopsy periprosthetic synovial tissue of failed THA to rule out PJI. We found similar diagnostic performance as compared with traditional US-JA. This supports future larger studies on this procedure that might be applied in patients without joint effusion. 相似文献
995.
《The Foot》2021
IntroductionThe repair of a deltoid ligament injury, following an ankle fracture with involvement of the syndesmosis, has no univocal consensus. Also the surgical strategies in case of a subsequent chronic instability are still under debate. In this work the result of a double bundle anatomic reconstruction of deltoid ligament with ipsilateral autologous gracilis muscle tendon is presented.Case reportA 50 year old active male patient came to our attention with a catastrophic medial ankle instability, a severe pronation of the hindfoot and disabling ankle pain. He reported a Weber type B fracture of the left ankle with a lesion of the syndesmosis treated with anatomic plate and screws and a transyndesmotic screw 8 months before. The imaging showed a complete deltoid ligament lesion. Due to the impossibility of a direct repair of the ligament, we performed the reconstruction of the medial ligamentous complex with an autologous gracilis tendon graft. 10 months after the medial ligamentous complex reconstruction, the patient showed an excellent recovery of walking ability, disappearance of pain under load and resumed an active lifestyle.DiscussionThe deltoid ligament has a key role in ankle joint stability and its integrity promotes the recovery after ankle fractures. However, its lesion is often left untreated in the acute setting. The result of a chronic untreated deltoid ligament injury could be extremely disabling and the ligament reconstruction, when an optimal native deltoid ligament repair is not achievable, is the choice to restore ankle function and stability.ConclusionIn the delayed treatment of a deltoid ligament rupture the described double bundle anatomic reconstruction with autologous tendon graft can be an effective and suitable option. 相似文献
996.
BackgroundNon-union is a significant complication of fracture fixation surgery, and can negatively impact a patient’s quality of life. Low intensity pulsed ultrasound (LIPUS) has been used to treat delayed or non-unions previously in the literature. The aim of this study was to determine the success rate of LIPUS treatment in patients with chronic fracture non-unions, and to establish the effect of systemic or local factors on its success.MethodsThis was a retrospective, observational study which included all patients undergoing LIPUS treatment in a single institution. Patients deemed suitable for LIPUS underwent treatment for a period of 6 months from initiation. They were followed up with sequential radiographs to assess union at intervals of 6 weeks, 3 months, 6 months and 1 year. LIPUS treatment was considered to be successful when patients achieved clinical and radiological union, without the need for revision surgery.ResultsA total of 46 patients were included in the study; 8 were lost to follow – up, leaving 38 patients for the final analysis. The mean age of patients was 47.03 ± 19.7 with a male to female ratio of 1.2:1. Union was achieved in 57.89%; the rest underwent revision surgery. There was no significant association between outcomes after LIPUS treatment and patients’ age, gender, smoking status or type of non-union. Patients with a small inter-fragment bone gap were more likely to have a successful outcome after LIPUS (p = 0.041). Time to treatment did not have a statistically significant impact on outcomes after LIPUS. Interestingly, all 6 patients with diabetes in the study managed to achieve union after LIPUS.ConclusionsThis study demonstrates that LIPUS is not successful in a large proportion of patients with established fracture non-unions. However, it does represent a low risk treatment modality as an alternative to revision surgery, especially for patients with diabetes who have a small inter – fragment bone gap. More research in the form of large randomised controlled trials needs to be carried out to further assess the role of LIPUS in the treatment of non-unions. 相似文献
997.
Nerves are commonly injured in case of blunt or penetrating trauma to the extremities. Patients with nerve injuries have profound consequences and thus a timely decision for operative management is a very important. Conventionally, management decisions have been based on clinical findings, patient course and electrophysiological studies. However, imaging modalities have an enormous role not only in localizing and grading of the nerve injuries but also in the follow-up of the nerve recovery. High-resolution ultrasound (HUS) is the modality of choice for evaluation of peripheral nerves. Magnetic resonance neurography (MRN) plays a complementary role, enabling better assessment of muscle changes and deeper nerves. Corresponding to the injured layer of the cross-section of the nerve, imaging manifestations differ in different grades of injury. Since imaging cannot detect ultrastructural changes at the microscopic level, thus there may be overlap in the imaging findings. Herewith, we discuss the imaging findings in different grades of nerve injury and propose a simple 3-tier grading for imaging (HUS and MRN) assessment of peripheral nerve injuries. 相似文献
998.
目的观察丁苯酞预处理对心肌缺血再灌注损伤的保护作用以及磷酸肌醇3激酶(PI3K)/蛋白激酶B(Akt)通路在此过程中的作用。方法将大鼠心肌细胞(H9C2)随机分为假手术组(Sham组)、缺血再灌注组(I/R组)、丁苯酞预处理组(I/R+NBP组)。通过氧气剥夺以及无糖培养基的更换模拟6 h缺血4 h复灌心肌缺血模型。通过细胞计数检测试剂盒(CCK-8)检测不同药物浓度细胞活性,探索丁苯酞的最佳药物浓度;比色法检测各组乳酸脱氢酶(LDH)以及丙二醛(MDA)含量;蛋白质印迹法(Western blot)检测PI3K、磷酸化蛋白激酶B(p-Akt)和Akt的蛋白表达水平;定量聚合酶链反应(qPCR)技术检测白细胞介素-1β(IL-1β)和肿瘤坏死因子-α(TNF-α)在核糖核酸(mRNA)水平的表达。多组之间比较采用单因素方差分析,两组之间比较采用t检验。结果丁苯酞的最佳用药浓度为100μmol/L;I/R组MDA、LDH的表达量高于Sham组[(172.03±14.99)nmol/L比(38.98±6.49)nmol/L、(195.04±14.50)%比(100.00±0.00)%,t=14.106、11.354,P<0.05];I/R组IL-1β、TNF-α的表达量高于Sham组(22.36±2.71比1.00±0.00、6.20±0.31比1.00±0.00,t=13.660、28.874,P<0.05);I/R组PI3K、p-Akt的表达量也高于Sham组(0.61±0.34比0.34±0.01、0.95±0.04比0.36±0.04,t=13.487、18.392,P<0.05),差异有统计学意义。I/R+NBP组MDA、LDH的表达量低于I/R组[(56.98±4.79)nmol/L比(172.03±14.99)nmol/L、(140.34±4.44)%比(195.04±14.50)%,t=12.661、7.890,P<0.05];I/R+NBP组IL-1β、TNF-α的表达量低于I/R组(6.66±0.60比22.36±2.71、1.76±0.11比6.20±0.31,t=9.798、23.352,P<0.05),差异有统计学意义;I/R+NBP组PI3K、p-Akt的表达量高于I/R组(1.00±0.05比0.61±0.34、1.27±0.04比0.95±0.04,t=11.440、10.432,P<0.05),差异有统计学意义。结论丁苯酞可以通过减少细胞损伤、抑制氧化及炎性反应进而减轻心肌缺血再灌注损伤,该过程可能有PI3K/Akt通路的参与。 相似文献
999.
目的探讨锌指蛋白 A20 对兔腰椎间盘退变的影响。方法取 3 月龄新西兰大白兔 26 只,体质量 2.0~2.5 kg,经腹细针穿刺法制备 L3、4、L4、5、L5、6 椎间盘退变模型,其中 24 只术后 4 周 MRI 检查明确造模成功,随机分为 4 组(n=6),于目标椎间盘中分别注射锌指蛋白 A20 过表达腺病毒(过表达 A20 组)、空载体腺病毒(空载体组)、PBS 液(对照组)、锌指蛋白 A20干扰腺病毒(干扰 A20 组)。于注射前 1 d 及注射后 1、2、3、6 d 行生物反应综合评分;注射后 2、4、8 周,各组行 MRI 检查并测量 T2 弛豫时间(T2 信号值)后,取材行阿利辛蓝染色观察椎间盘髓核细胞退变情况,免疫组织化学染色检测锌指蛋白 A20 以及椎间盘退变相关指标(Ⅱ型胶原、蛋白聚糖)的表达,Western blot 检测锌指蛋白 A20、NF-κB 结合蛋白[P65、磷酸化 P65(phosphate P65,P-P65)、Ⅱ型胶原、蛋白聚糖]、自噬相关蛋白[LC3 (LC3Ⅱ/LC3Ⅰ)、P62]以及炎症因子(TNF-α、IL-1β)的表达。 结果各组注射后各时间点生物反应综合评分均明显低于注射前 1 d(P<0.05);注射后 6 d 干扰 A20 组评分明显低于其他组(P<0.05),其他组间比较差异均无统计学意义(P>0.05)。MRI 检测提示,注射后 2、4、8 周过表达 A20 组 T2 信号值均最高(P<0.05),2、4 周时干扰 A20 组最低(P<0.05),其余组间差异均无统计学意义(P>0.05)。阿利辛蓝染色显示,注射后 4 周过表达 A20 组蛋白聚糖含量最高(P<0.05)、干扰 A20 组最低(P<0.05);8 周时过表达 A20 组蛋白聚糖含量显著高于其他组(P<0.05),其他组间比较差异无统计学意义(P>0.05)。免疫组织化学染色示,锌指蛋白 A20、Ⅱ型胶原、蛋白聚糖表达过表达 A20 组最高(P<0.05),干扰 A20 组上述蛋白表达最低(P<0.05)。Western blot 检测示锌指蛋白 A20、蛋白聚糖、Ⅱ型胶原、LC3 (LC3Ⅱ/LC3Ⅰ)蛋白相对表达量过表达 A20 组最高、干扰 A20 组最低,而 P-P65、TNF-α、IL-1β、P62 蛋白相对表达量过表达 A20 组最低、干扰 A20 组最高,与其他组比较差异均有统计学意义(P<0.05);各组 P65 蛋白相对表达量差异均无统计学意义(P>0.05)。 结论锌指蛋白 A20 能通过抑制炎症反应,有效延缓兔腰椎间盘退变的进程。 相似文献
1000.
Whitney Sutton Joseph K. Canner Lisa M. Rooper Jason D. Prescott Martha A. Zeiger Aarti Mathur 《American journal of surgery》2021,221(1):111-116
BackgroundCurrent data regarding the risk of malignancy in a large thyroid nodule with benign fine-needle aspiration biopsy(FNAB) is conflicting. We investigated the impact of patient age on the risk of malignancy in nodules≥4 cm with benign cytology.MethodsWe performed a single-institution retrospective review of patients who underwent surgery from 07/2008–08/2019 for a cytologically benign thyroid nodule ≥4 cm. The relationship between malignant histopathology and patient and ultrasound features was assessed with multivariable logistic regression.ResultsOf 474 nodules identified, 25(5.3%) were malignant on final pathology. In patients <55 years old, 21/273(7.7%) nodules were malignant, compared to 4/201(2.0%) in patients ≥55. Patient age ≥55 was independently associated with significantly lower risk of malignancy(OR:0.2,95%CI:0.1–0.7,p = 0.011). Increasing nodule size >4 cm and high-risk ultrasound features were not associated with risk of malignancy(OR:1.0,95%CI:0.7–1.4,p = 0.980, and OR:9.6,95%CI:0.9–107.8,p = 0.066, respectively).ConclusionsPatients <55 years old are 3.7-fold more likely to have a falsely benign FNA biopsy in a nodule≥4 cm. 相似文献