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31.
目的:探讨血管紧张素Ⅱ(Ang Ⅱ)介导的钙调神经磷酸酶(CaN)信号通路参与心力衰竭(CHF)患者心肌重塑的机制。方法:选择因瓣膜性心脏病接受二尖瓣置换术的CHF病人39例,正常对照38例(其中8例来自意外伤亡的器官捐献者)。彩色多普勒超声心动图仪检测心脏扩大和心功能参数。放免法检测血浆及心肌组织Ang Ⅱ浓度,免疫沉淀法测心肌组织CaN、活化T细胞核因子(NFAT3)、锌指转录因子(GATA4)磷酸化及蛋白表达,RT-PCR检测肌球蛋白重链(β-MHC)mRNA表达。结果:AngⅡ分别与心脏扩大参数呈显著正相关,而与心功能参数呈显著负相关。CHF患者心肌组织CaN蛋白表达、CaN磷酸化、GATA4蛋白表达及β-MHC mRNA表达明显高于对照组,随心功能恶化其表达逐渐增加;NFAT3磷酸化随心功能恶化而减弱。结论:肾素血管紧张素系统(RAS)激活的CaN信号通路在CHF患者心肌重构机制中可能起重要作用。  相似文献   
32.
We describe a case of indolent vascular prosthesis infection due to Propionibacterium acnes. The microorganism was identified only by amplification and sequencing of 16S rDNA, while standard cultures remained negative. This observation underscores the usefulness of molecular techniques for the diagnosis of infection caused by fastidious microorganisms.  相似文献   
33.
心脏瓣膜置换术48例围手术期的处理   总被引:1,自引:1,他引:0  
目的:总结瓣膜置换术围手术期处理所临床经验。方法:回顾性分析48例瓣膜置换术病人术前、术中、术后处理的临床资料。结果:发生围手术期并发症共14例,其中低心排4例,心律失常4例最多。长期存活47例,死于多器官功能衰竭1例。结论:术前注意纠正心功能不足与合并症的治疗,术中注意心肌保护与三尖瓣关闭不全的矫治,术后强调补足血容量和血清钾后强心利尿。  相似文献   
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35.
Diabetes mellitus is associated with increased risk of erectile dysfunction. Penile prosthesis implantation is an efficient therapeutic option for erectile dysfunction, but not without risk, as infection remains a prominent concern. This study investigates diabetes mellitus as a risk factor for penile prosthesis implantation infection and the relationship between haemoglobinA1c levels and infection rates. All diabetic patients with erectile dysfunction who underwent penile prosthesis implantation surgery between January 2012 and November 2019 at Hamad Medical Corporation, Qatar, were included in this retrospective observational study. A total of 599 diabetic patients with erectile dysfunction had penile prosthesis implantation. Mean age was 59.69 ± 31.19. Penile prosthesis implantation infection rate was 0.83% (5/599), while the mean haemoglobinA1c level was 7.58 ± 1.45 mmol/l (range: 4.1–12.6). A comparison between diabetic patients with penile prosthesis implantation infection and those without infection revealed no significant difference in the level of haemoglobinA1c between the two groups with mean haemoglobinA1c in patients with infected implants 7.14 and 7.59 for noninfected (p = 0.491). Limitations include retrospective single-centre design and low-infection rates reducing sample number. Penile prosthesis implantation infection rate in a large series of diabetic patients was low with no significant association between haemoglobinA1c level and penile prosthesis implantation infection observed.  相似文献   
36.
《The Journal of arthroplasty》2021,36(9):3226-3232
BackgroundThe average age of patients benefiting from total hip arthroplasty (THA) has been declining. In addition to pain relief, patients seek to return to physical activity. However, the latter may increase polyethylene wear and therefore the potential risk of early aseptic loosening. The introduction of highly crosslinked polyethylene (HXLPE) has reduced wear rates in the general patient population. The objective of this study was to evaluate the influence of impact sports in patients operated with THA using ceramic-on-conventional polyethylene (cPE) versus ceramic-on-HXLPE, in terms of wear and function, with a minimum of five year follow-up.MethodsSixty-eight patients practicing an impact sport (University of California Los Angeles score ≥8) who underwent a primary THA were included: 34 with a ceramic-on-cPE versus 34 with a ceramic-on-HXLPE using the same cementless acetabular and femoral component. Patients were matched-paired by age, sex, BMI, and University of California Los Angeles score. The wear analysis was performed using the IMAGIKA software. The Harris hip score and hip and osteoarthritis outcome score were collected.ResultsThe linear wear rate was statistically higher (P < .0001) in the cPE group (0.13503 ± 0.0630 mm/year) than in the HXLPE group (0.03059 ± 0.0084 mm/year). Postoperatively, the increase in Harris hip score was calculated at 37.64 for the entire cohort and was comparable in both groups (P = .3674). The hip and osteoarthritis outcome score for pain (P = .0009), daily life activities (P = .0016), and quality of life (P = .0179) were significantly higher in the HXLPE group, with, between groups, a difference inferior to the reported minimal clinical important difference. Three patients exhibited signs of periprosthetic osteolysis in the cPE group, one on the femoral side and two on the acetabular side. None were observed in the HXLPE group. No revision for aseptic loosening was reported in both cohorts.ConclusionPatients partaking in impact sports and receiving a ceramic-on-HXLPE THA demonstrated lower wear and osteolysis rates than those having a ceramic-on-cPE THA, with similar functional results.  相似文献   
37.
目的 探讨长链非编码RNA KLHL7-DT对人退变髓核细胞增殖和凋亡的影响及其相关机制。方法 选取2018年1月—2019年10月南京江北医院骨科脊柱骨折患者手术切除的正常椎间盘标本18例,其中男11例、女7例,年龄为22~46 (38.3±4.3)岁,PfirrmannⅠ级6例、Ⅱ级12例。取椎间盘标本常规分离、培养髓核细胞,使用10 ng/mL IL-1β处理髓核细胞获得退变髓核细胞。将退变髓核细胞分为沉默对照组、KLHL7-DT沉默组、过表达对照组、KLHL7-DT过表达组。4组细胞分别对应转染沉默对照序列、siRNA-KLHL7-DT沉默序列、过表达对照序列、KLHL7-DT过表达序列。取转染后4组退变髓核细胞采用5-乙炔基-2’脱氧尿嘧啶核苷(EdU)法检测细胞增殖情况,流式细胞术检测细胞凋亡情况,Western blot检测聚集蛋白聚糖(Aggrecan)、Ⅱ型胶原(Col Ⅱ)蛋白的表达情况。结果 (1)KLHL7-DT过表达组EdU染色阳性细胞/DAPI染色阳性比值(0.147±0.002)低于过表达对照组(0.203±0.007),而KLHL7-DT沉默组比值(0.428±0.050)高于沉默对照组(0.240±0.032),差异均有统计学意义(t=14.25、-5.44,P值均<0.05)。(2)KLHL7-DT过表达组细胞凋亡率(19.01%±0.41%)高于过表达对照组(14.38%±0.31%),KLHL7-DT沉默组细胞凋亡率(16.08%±0.59%)低于沉默对照组(17.42%±0.36%),差异均有统计学意义(t=15.69、3.36,P值均<0.05)。(3)Western blot结果显示,KLHL7-DT过表达组细胞Aggrecan和Col Ⅱ蛋白的相对表达量(分别为0.34±0.29、0.57±0.11)均低于过表达对照组(1.00±0.22、1.05±0.10),KLHL7-DT沉默组Aggrecan和Col Ⅱ蛋白的相对表达量(分别为1.77±0.14、1.63±0.12)均高于沉默对照组(1.10±0.18、0.98±0.08),差异均有统计学意义(t=3.10、5.54、-5.05、-7.66,P值均<0.05)。结论 上调KLHL7-DT的表达可抑制退变髓核细胞的增殖,促进退变髓核细胞的凋亡,其机制可能是通过调节细胞外基质Aggrecan、Col Ⅱ蛋白的合成,进而参与椎间盘退变的发展。  相似文献   
38.
39.
BackgroundPenile prostheses are the third option in the treatment of erectile dysfunction, however, despite their proven effectiveness, the occurrence of infections, advanced age of patients and comorbidities are the main limiting factors for this treatment modality. In the continuous search for biointegrated, clinically durable and minimally invasive treatment options, a possible model of penile prosthesis was sought through the use of intracavernous bacterial cellulose (BC) gel, in an experimental model of orchiectomized rabbits.MethodsThirty adult New Zealand rabbits were equally distributed into three groups: BC; vehicle and control. Each group was then subdivided according to the follow-up time of 3 and 6 months. Bilateral orchiectomy was performed 3 weeks before injection in the BC and vehicle groups. Pachymetry measurements of the penile axis, diameter and length were performed in situ. Histomorphometry analyzes of the corpora cavernosa (CC), thickness of the tunica albuginea, cell density, collagen and elastic fibers post-injection were also performed, in addition to immunohistochemistry for newly formed vessels.ResultsThe implant of BC increased both the length and thickness of the penis three and six months after the last injection, with a consequent increase in the diameter of the CC. On the other hand, the filling effect was not observed in the control and vehicle groups, confirming the degradation of this tissue after orchiectomy and the effectiveness of BC as a filling agent. Histomorphometry analyzes corroborate the mass effect of BC integrated into the tissue, permeated by predominantly lymphomononuclear inflammatory infiltrate, multinucleated giant foreign body cells, fibroblasts, elastic fibers and newly formed vessels, without degradation or loss of volume, even after six months of implantation.ConclusionsBiocompatibility and biointegration to the host tissue make BC a prosperous penile filling material, with local application and minimally invasive.  相似文献   
40.
Electronic chips that provide a patterned stimulus to cells in the retina may provide a viable treatment for age-related macular degeneration. A surrogate MEMS device, in the form of a print-head from a desktop printer, has been used to eject a pattern of neurotransmitters (bradykinin) onto living rat pheochromocytoma (PC12) cells. Fluorescent calcium imaging was used to measure the patterned stimulation of individual cells. The chemical stimulation of cells by directed microfluidic delivery may have applications in retinal prosthetic devices, and in other prosthetic implants in the nervous system.  相似文献   
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