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101.
《中国现代医生》2020,58(31):130-133+141
目的 研究产褥感染的危险因素及常见致病微生物耐药情况,为临床治疗提供参考。方法 回顾性分析我院2017 年1 月~2019 年12 月发生的84 例产褥感染病例的临床资料,与同时期未发生产褥感染的200 例产妇进行对照研究,分析产褥感染的影响因素,并对分离获得的致病微生物进行耐药性分析。结果 感染组妊娠糖尿病、产钳助产、宫口开全后中转剖宫产患者的分布率高于对照组,差异有统计学意义(P<0.05);经多因素Logistic 回归分析,妊娠糖尿病是产褥感染的独立影响因素(P<0.05)。本研究中共检出致病微生物40 株,其中革兰阴性菌13 株(占32.50%),革兰阳性菌10 株(占25.00%),支原体16 株(占40.00%),衣原体1 株(占2.50%),革兰阴性菌中以大肠埃希菌最常见,对二代头孢菌素类抗生素耐药率20%。革兰阳性菌以金黄色葡萄球菌最常见,对青霉素及头孢菌素耐药率高,未发现对亚胺培南及万古霉素耐药。结论 产钳助产、妊娠糖尿病、宫口开全后中转剖宫产是产褥感染可能的危险因素,其中,妊娠糖尿病是产褥感染的独立危险因素。目前临床常见致病微生物谱及耐药率未发生明显变化。 相似文献
102.
Leah H. Cobb Emily M. McCabe Lauren B. Priddy 《Journal of orthopaedic research》2020,38(10):2091-2103
Osteomyelitis, or the infection of the bone, presents a major complication in orthopedics and may lead to prolonged hospital visits, implant failure, and in more extreme cases, amputation of affected limbs. Typical treatment for this disease involves surgical debridement followed by long-term, systemic antibiotic administration, which contributes to the development of antibiotic-resistant bacteria and has limited ability to eradicate challenging biofilm-forming pathogens including Staphylococcus aureus—the most common cause of osteomyelitis. Local delivery of high doses of antibiotics via traditional bone cement can reduce systemic side effects of an antibiotic. Nonetheless, growing concerns over burst release (then subtherapeutic dose) of antibiotics, along with microbial colonization of the nondegradable cement biomaterial, further exacerbate antibiotic resistance and highlight the need to engineer alternative antimicrobial therapeutics and local delivery vehicles with increased efficacy against, in particular, biofilm-forming, antibiotic-resistant bacteria. Furthermore, limited guidance exists regarding both standardized formulation protocols and validated assays to predict efficacy of a therapeutic against multiple strains of bacteria. Ideally, antimicrobial strategies would be highly specific while exhibiting a broad spectrum of bactericidal activity. With a focus on S. aureus infection, this review addresses the efficacy of novel therapeutics and local delivery vehicles, as alternatives to the traditional antibiotic regimens. The aim of this review is to discuss these components with regards to long bone osteomyelitis and to encourage positive directions for future research efforts. 相似文献
103.
Yu‑Xiang Zhang Zhong‑Chen Gao Ye‑Xin Liu Wei Li 《World Journal of Traditional Chinese Medicine》2020,6(4)
Background: As the demand for traditional Chinese medicinal materials increases in China and even the world, there is an urgent need for an effective and simple identification technology to identify the origin and quality of the latter and ensure the safety of clinical medication. Mineral element analysis and isotope finger-printing are the two commonly used techniques in traditional origin identification. Both of these techniques require the use of stoichiometric methods in the identification process. Although they have high accuracy and sensitivity, they are expensive and inefficient. In addition, near-infrared spectroscopy is a fast, nondestructive, and widely used identification technique developed in recent years, but its identification results are susceptible to samples’ states and environmental conditions, and its sensitivity is low. Hyperspectral imaging combines the advantages of imaging technology and optical technology, which can simultaneously access the image information and spectral information which reflect the external characteristics, internal physical structure, and chemical composition of the samples. Hyperspectral imaging is widely applied to agricultural product inspection, but research into its application in origin and quality identification of TCM materials is rare. Methods: In this study, the algorithm framework discriminative marginalized least squares regression (DMLSR) was used for feature extraction of frankincense hyperspectral data. The DMLSR with intraclass compactness graph and manifold regularization can efficiently learn the projective samples with higher separability and less redundant information than the original samples. Then, the discriminative collaborative representation with Tikhonov regularization (DCRT) was applied for classifying the geographical origin and level of frankincense. DCRT introducesthe discriminant regularization term and incorporates SID, which is more sensitive to the spectrum as the measurement method and is more suitable for the frankincense spectral data compared with SVM. Results: For the origin classification task, samples of all levels from each origin were, respectively, selected for three?way classification. We used 10-fold cross-validation to select a model parameter in the experiment. When obtaining the optimal parameters, we randomly selected the training set and testing set, where the training set accounts for 70% and the training set for 30%. After repeating this random process 10 times, we obtained the final average classification accuracy, which is higher than 90%, and the standard deviation fluctuation is usually small. For the level classification task, samples of each level from three origins were separately selected for multiclassification. We randomly selected the training set and testing set from each origin. The level classification results of the three origins are good on D4350 data, and the classification accuracy of each level is basically above 80%. Conclusion: Experiments and analysis show that our algorithm framework has excellent classification performance, which is stable in origin classification and has potential for generalization. In addition, the experiments show that in our algorithm framework, different classification tasks need to combine different data sources to achieve better classification and recognition, as the origin classification task uses frankincense’s D3000 data, and level classification task uses frankincense’s D4350 data. 相似文献
104.
105.
铜绿假单胞菌噬菌体PaP3生物学特性的研究 总被引:2,自引:0,他引:2
目的测定铜绿假单胞菌噬菌体PaP3的最佳感染复数、一步生长曲线和吸附K值及交叉吸附K值等基本生物学特性。方法按照感染复数(MOI)分别为0.0001、0.001、0.01、0.1、1和10加入噬菌体纯培养液和宿主菌,充分裂解细菌后,测定噬菌体滴度;以MOI=10的比例加入噬菌体及宿主菌,进行一步生长实验;纯化PaP3颗粒,免疫家兔,获得抗血清,通过中和反应实验测定PaP3和其抗血清之间的吸附反应常数K值。同时,利用抗血清交叉中和试验确定本室分离的三株噬菌体之间的血清学关系。结果当MOI=0.001时PaP3感染其宿主菌产生的子代噬菌体滴度最高;根据一步生长实验结果绘制一步生长曲线;通过血清交叉中和反应得出不同的吸附常数。结论PaP3最佳感染复数为0.001,感染宿主菌的潜伏期是20min,爆发期是60min,平均爆发量约为31,其抗血清反应的吸附常数K值为262。 相似文献
106.
107.
影响颅脑外伤术后颅内感染的危险因素分析 总被引:6,自引:0,他引:6
目的探讨影响颅脑外伤开颅术后颅内感染的危险因素。方法采用回顾性研究比较分析了912例颅脑损伤术后出现颅内感染与未出现颅内感染组间的差异因素。结果非感染 770例,颅内感染142例(15.6%)。感染类型有无菌性脑膜炎、细菌性脑膜炎、脑室炎及脑室积脓、脑脓肿、硬膜下腔积脓、术区皮下或(和)骨瓣下化脓或合并骨髓炎、切口感染。细菌检出率占感染的27.5%。颅脑外伤术后感染与高温季节、高龄、重度以上损伤、短期内两次以上手术、连续两侧开颅术、长时间 (>5 h)手术、显微外科手术、颅底与后颅凹手术、脑室外引流、皮下或硬膜外积液以及急诊手术等因素相关(P<0.05)。结论对具有上述危险冈素的易感患者应给予更密切的关注和预防性的处理。 相似文献
108.
109.
原位肝移植术后缺血型胆道病变20例 总被引:1,自引:1,他引:0
目的探讨原位肝移植术后缺血型胆道病变(ITBL)的病因及预防、诊断和治疗的措施。方法回顾性分析1999年2月至2005年4月间291例次原位肝移植后发生ITBL患者的临床资料。结果291例次原位肝移植术后共发生ITBL 20例(6.9%)。术后发生ITBL的高危因素为:原发病为重型乙型肝炎、供受者ABO血型不符、供肝冷保存时间超过12h和术后肝动脉病变。其发生率分别为12.5%(9/71)、20.0%(2/10)、11.1%(9/81)和60%(3/5)。采用药物、经内镜逆行胰胆管造影(ERCP)介入、胆道外科手术及再次肝移植等方法治疗,有效率为80.0%(16/20)、治愈率为50.0%(10/20),与ITBL相关的病死率为10.0%(2/20),与ITBL相关的移植物功能丧失发生率为20.0%(4/20)。结论针对ITBL的高危因素进行相应处理是预防ITBL的有效措施。胆道造影和核磁共振胆胰管成像对诊断ITBL有很高的敏感性和特异性。根据不同的病因和病变程度采用适当的方法治疗ITBL,可获得良好的疗效。 相似文献
110.
AIM/BACKGROUND: Primary biliary cirrhosis (PBC) is a chronic cholestatic liver disease of unknown aetiology. Up to 10% of patients with typical features of PBC will have additional features of autoimmune hepatitis (AIH). A subset, however, have no such features but go on to develop a 'sequential' AIH overlap syndrome. Objectives: Describe our experience with eight patients who developed AIH after the diagnosis of PBC was made. METHODS: We reviewed the charts of all PBC patients over a 9-year period (from 1996 to 2005). Only PBC patients with no features of AIH were included. RESULTS: There were 1476 patients with PBC. Of these, eight patients developed features of AIH overlap syndrome based on biochemical and histological parameters. Treatment included prednisone and azathioprine for 24 or more months. The majority of patients remained on ursodeoxycholic acid (UDCA) throughout treatment. Response to therapy was defined by improvement in enzymes, and was rapid for all patients. One patient was able to discontinue treatment with prednisone and azathioprine, while seven have continued on therapy to date. CONCLUSIONS: A 'sequential' overlap syndrome of AIH with PBC can occur. Treatment with prednisone and azathioprine may lead to a rapid improvement in aminotransferase levels. 相似文献