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1.
宫腔化脓性感染是一种严重的盆腔炎性疾病(PID),主要表现为发热、腹痛、阴道分泌物增多等症状。椎间盘炎是发生于椎间盘间隙和邻近椎体或软骨板的感染性病变,其症状及体征缺乏特异性,临床上容易诊断延迟直至出现椎体骨质破坏及下肢肌力减弱。本文报道了1例因取环手术引发宫腔化脓性感染进而引发腰椎间盘炎,出现腰痛伴行走障碍的患者,并进行了文献复习,加深了对PID的病原体、感染传播途径、诊断标准、治疗原则及其严重不良后果的认识。对于非特异性椎间隙感染,临床医生除实验室检查及影像学检查之外,还应仔细询问病史并了解病情的演变过程,及时诊断并进行手术治疗。  相似文献   
2.
[摘要] 目的 探讨ICU患者发生产超广谱β-内酰胺酶(extended spectrum beta-lactamases, ESBLs)革兰阴性杆菌感染的危险因素,并构建相关预测模型。方法 选取2017年5月—2021年4月我院ICU发生大肠埃希菌或肺炎克雷伯菌感染的189例患者作为研究对象,收集患者的临床资料,使用单因素分析、LASSO回归和多因素Logistic回归分析ICU患者30 d内发生产ESBLs革兰阴性杆菌感染的危险因素,并据此建立列线图预测模型。结果 急性生理与慢性健康评分≥16分、留置尿管时长≥7 d、抑酸剂使用时长≥3 d、第三代头孢菌素使用时长≥3 d、抗菌药物联用时长≥3 d和ICU住院时间≥15 d是ICU患者30 d内发生产ESBLs革兰阴性杆菌感染的危险因素(P均<0.05)。依此建立预测ICU患者30 d内发生产ESBLs革兰阴性杆菌感染的列线图风险模型,模型验证结果显示C-index为0.795,校正曲线趋近于理想曲线,AUC为0.807(95%CI:0.775~0.839),在2%~81%预测范围内,列线图净获益。结论 ICU患者30 d内发生产ESBLs革兰阴性杆菌感染的危险因素包括APACHEⅡ评分≥16分、留置尿管时长≥7 d、抑酸剂使用时长≥3 d、第三代头孢菌素使用时长≥3 d、抗菌药物联用时长≥3 d和ICU住院时间≥15 d,据此构建的列线图模型能有效预测ICU患者30 d内发生产ESBLs革兰阴性杆菌感染的风险概率,具有一定的临床价值。  相似文献   
3.
The current literature suggests that the antibacterial effect of leukocyte- and platelet-rich plasma (L-PRP) is directly related to platelet and leukocyte concentrations. The aim of this study was twofold: first, to evaluate the antimicrobial effect of L-PRP against selected bacterial strains in vitro, and second, to correlate this effect with leukocyte and platelet content in the final concentration. Blood was collected from 20 healthy males, and L-PRP, acellular plasma (AP), and autologous thrombin were consecutively prepared. Flow cytometry analysis of the blood, L-PRP, and AP was performed. The L-PRP gel, liquid L-PRP, and thrombin samples were tested in vitro for their antibacterial properties against seven selected bacterial strains using the Kirby–Bauer disk-diffusion method. There was notable antimicrobial activity against selected bacterial strains. No statistically significant correlations between antimicrobial activities and the platelet concentration in L-PRP were observed. Statistically significant positive correlations between selected leukocyte subtypes and antimicrobial activity were noted. A negative correlation was found between elevated monocyte count and antimicrobial activity of L-PRP against one bacterial strain studied. L-PRP possesses antimicrobial activity and can be potentially useful in the fight against certain postoperative infections. The bactericidal effect of L-PRP is caused by leukocytes, and there exists a relationship among selected leukocyte subtypes and L-PRP antimicrobial activity.  相似文献   
4.
5.
Upon infection or brain damage, microglia are activated to play roles in immune responses, including phagocytosis and soluble factor release. However, little is known whether the event of phagocytosis could be a trigger for releasing soluble factors from microglia. In this study, we tested if microglia secrete a neurovascular mediator matrix metalloproteinase-9 (MMP-9) after phagocytosis in vitro. Primary microglial cultures were prepared from neonatal rat brains. Cultured microglia phagocytosed Escherichia coli bioparticles within 2 hr after incubation and started to secrete MMP-9 at around 12 hr after the phagocytosis. A TLR4 inhibitor TAK242 suppressed the E. coli-bioparticle-induced MMP-9 secretion. However, TAK242 did not change the engulfment of E. coli bioparticles in microglial cultures. Because lipopolysaccharides (LPS), the major component of the outer membrane of E. coli, also induced MMP-9 secretion in a dose–response manner and because the response was inhibited by TAK242 treatment, we assumed that the LPS-TLR4 pathway, which was activated by adhering to the substance, but not through the engulfing process of phagocytosis, would play a role in releasing MMP-9 from microglia after E. coli bioparticle treatment. To support the finding that the engulfing step would not be a critical trigger for MMP-9 secretion after the event of phagocytosis in microglia, we confirmed that cell debris and amyloid beta were both captured into microglia via phagocytosis, but neither of them induced MMP-9 secretion from microglia. Taken together, these data demonstrate that microglial response in MMP-9 secretion after phagocytosis differs depending on the types of particles/substances that microglia encountered.  相似文献   
6.
大肠杆菌O-抗原血清型鉴定研究进展   总被引:1,自引:0,他引:1  
大肠杆菌在一定条件下能引发宿主疾病,其表面O-抗原与毒力有关。O-抗原的化学组成和结构具有高度多样性,并且O-抗原血清型种类与大肠杆菌致病性有一定联系。因此,大肠杆菌O-抗原血清型鉴定对流行病学调查,防御和控制致病性大肠杆菌病有重要意义。传统的血清学分型方法耗时长、费用高、准确度不理想。随着科学技术的发展,研究者对大肠杆菌196种O-抗原基因簇进行了破译,比较分析了不同O-抗原基因簇序列,并针对基因簇中特异性DNA序列设计分子标记,运用PCR方法对O-抗原血清型进行分型,其中包括一般PCR、多重PCR、实时PCR、DNA芯片和微球悬浮列阵法。此外,还有rbf-限制性片段长度多态性分析法,磁性微球免疫分析法和基于全基因组序列预测法,这些方法丰富了O-抗原血清型鉴定方法,弥补了传统血清学分型方法的不足。本文概述了O-抗原合成基因簇序列和O-抗原血清型鉴定方法相关研究进展。  相似文献   
7.
Curcumin nanoparticles were most recently considered in medical research because of their antibacterial properties. The main objective of the study was to develop the green synthesis and antibacterial activity of curcumin nanoparticles using Curcuma longa. The processing of curcumin nanoparticles was carried out after the collection, identification, and extraction of curcumin. The effect of a sample on the synthesis of nanoparticles, such as curcumin aqueous concentrations (5, 10, and 20 mg/ml) and curcumin nanoparticles (5, 10, and 20 mg/ml), and the antibacterial effect of these nanoparticles on Escherichia coli, Staphylococcus aureusPseudomonas aeruginosa, Klebsiella pneumoniae, and the fungal strain Aspergillus niger. For examining antibacterial and anti-fungal activity disc diffusion method was performed, followed by the zone of inhibition. According to X-ray diffraction and scanning electron microscope analysis, nanoparticles have spherical shapes and size of 42.64 nm. Results showed that a high dose of 20 mg/ml curcumin nanoparticles have more antibacterial activity than curcumin extracts in E. coli as it showed the largest diameter of zone of inhibition as compared to other doses. Other bacterial and fungal strains also showed significant results but E. coli was most prominent. The biosynthesis of curcumin nanoparticles using an aqueous extract of C. longa is a clean, inexpensive, and safe method that has not been used any toxic substance and consequently does not have side effects. Since several pathogenic species have acquired antibiotic resistance, the combination of curcumin with various nanoparticles would be beneficial in the cure of pathogenic diseases.  相似文献   
8.
Since its identification as a unique species in 1982, Escherichia hermannii has only recently been implicated as a pathogenic organism in human diseases. Literature search indicates removal of hemodialysis catheter as being essential to the success of treatment for bacteremia with this organism. However, having no alternative access for hemodialysis led to the attempt to salvage the catheter with the use of Antibiotic lock therapy. This case highlights Antibiotic lock therapy as an indication in Escherichia hermanii Catheter related Bloodstream infection.  相似文献   
9.
吴昊 《安徽医学》2005,26(5):358-360
目的了解本地区医院分离出的产超广谱产β-内酰胺酶(ESBLs)的大肠埃希菌、肺炎克雷伯菌菌株的构成比及耐药特征,为临床制定合理的抗感染治疗方案提供参考。方法2003年10月1日至2004年9月30日从本地区五家医院各类临床标本分离的大肠埃希菌、肺炎克雷伯菌作为受试菌,采用Kirby-Bauer纸片扩散法和ESBLs确认试验进行ESBLs的检测及耐药性测定。结果产ESBLs的大肠埃希菌检出率为31%,肺炎克雷伯菌为31.6%,产ESBLs的大肠埃希菌及肺炎克雷伯菌株较不产ESBLs的菌株对各种临床常用抗生素耐药性明显增高,并表现出多重耐药。产ESBLs的大肠埃希菌及肺炎克雷伯菌株对临床常用的头孢呋辛、头孢噻肟、头孢哌酮、头孢曲松、氨曲南、阿莫西林/克拉维酸、替卡西林/克拉维酸、氨苄西林/舒巴坦的耐药率均超过70%,对头孢哌酮/舒巴坦的耐药率在50%左右,对氟喹诺酮类的耐药率在41.7%~72.7%,未发现对亚胺培南的耐药株。结论产ESBLs大肠埃希菌和肺炎克雷伯菌如此高的检出率应引起临床上高度重视,碳青霉烯类抗生素应该作为治疗产ESBLs菌严重感染的首选药物。  相似文献   
10.
Background: The impact of total body weight (TBW) on the development of acute kidney injury (AKI) associated with gram-negative bacteremia has not been previously evaluated.

Methods: The cohort included 323 patients >/ = 18 years old with gram-negative bacteremia (1/1/2008–8/31/2011) who received >/ = 48 hours of antibiotics. We compared the incidence of AKI in patients with a TBW </ = 80kg vs. >80kg with a multivariable stepwise logistic regression adjusting for age >/ = 70 years, baseline serum creatinine of > 2.0 mg/dl, and receipt of a vasopressor. AKI was defined as an increase of 0.5 mg/dL or a > 50% increase from baseline for at least two consecutive days.

Results: The cohort was 62% TBW </ = 80kg and 38% TBW >80kg. TBW >80kg patients had higher risk of AKI (24% vs. 9%, p < 0.001), which was significant in the multivariable analysis (OR 3.41, 95% CI 1.73–6.73). A baseline serum creatinine of > 2.0 mg/dl and vasopressor use were also independently associated with AKI.

Conclusions: TBW >80kg was associated with the development of AKI. However, the mechanism for this association is not clear.  相似文献   

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