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91.
目的分析成人分泌性中耳炎(OME)临床因素与预后的关系,找出影响成人OME治疗疗效的相关因素。方法收集291例(342耳)成人OME患者的基本资料,了解患者30 d内上呼吸道感染史、变应性疾病史、鼻及鼻窦疾病病史,评估患者咽鼓管功能。统计各临床因素与治疗有效率的相关性。比较上呼吸道感染是否合并咽鼓管功能不良与鼻及鼻窦疾病病史是否合并咽鼓管功能不良疗效的差异。结果①单因素分析显示,患者的性别(P=0.974)、单双侧发病情况(P=0.296)差异无统计学意义,与疾病疗效无明显相关性。而上呼吸道感染病史(P=0.049)与患者的疗效及预后呈正相关;鼻及鼻窦疾病病史(P=0.005)、咽鼓管功能状况(P=0.001)与患者的疗效及预后呈负相关,差异均有统计学意义。②多因素分析显示,上呼吸道感染病史(P=0.019,RR=1.692)、鼻及鼻窦疾病病史(P<0.001,RR=0.392)、咽鼓管功能不良(P<0.001,RR=0.248)仍与患者治疗疗效及预后相关。③鼻-鼻窦疾病病史合并咽鼓管功能不良治疗有效率明显降低(与鼻及鼻窦疾病病史且咽鼓管功能正常、上呼吸道感染合并或不合并咽鼓管功能不良相比,差异有统计学意义;慢性中耳炎发生率及鼓膜置管率明显升高,差异有统计学意义)。结论成人OME的危险因素为上呼吸道感染、鼻-鼻窦疾病、咽鼓管功能不良。鼻-鼻窦疾病合并咽鼓管功能不良是成人OME保守治疗效果欠佳的重要因素。  相似文献   
92.
While two-stage revision is the gold standard for treatment of knee prosthetic joint infection (PJI), it is not without risk. The purpose of this study was to develop a tool to preoperatively predict the probability that a two-stage revision would fail to eradicate knee PJI. 3,809 surgical cases were retrospectively reviewed and data were collected from 314 charts. Overall, 105 (33.4%) cases failed to eradicate PJI using this procedure. Univariate analysis identified multiple variables independently associated with reinfection. Logistic regression was used to generate a model (bootstrap-corrected concordance index of 0.773) predicting failure of infection eradication. Preoperative knowledge of a high probability of failure may improve risk assessment, lead to more aggressive management, and allow for time to consider alternative therapies.  相似文献   
93.
The objective of this retrospective study was to evaluate our results with one-stage revision using cementless femoral stem for infected hip arthroplasties. Twenty-four patients were included in the study. The acetabular component was cemented in 9 cases. In 2 patients a structured bone allograft was necessary to fill an acetabular defect. After a mean follow-up of 44.6 months, 23 patients showed no signs of infection (95.8%), the mean functional response according to the Merle d’Aubigné scale was 13.8 and the mean Harris Hip Score was 65.4. One-stage revision hip arthroplasty using cementless femoral stem was associated with a high success rate.  相似文献   
94.
95.
96.

Objectives

Study includes 20 patients with diagnosis of fascial space infections of odontogenic origin to assess efficacy of serum prealbumin and CRP levels as monitoring tools for determining severity of infections, nutritional status, hospital stay and efficacy of treatment.

Methods

Blood samples taken on day 0, 4, and 8 for measuring serum levels of markers. Simultaneously clinical parameters like swelling size, pain etc., were also recorded on day 0, 4, and 8 and appropriate treatment given to each patient. Correlation between markers and parameters was found using regression and paired t test.

Results

Statistical analysis found strong correlation between laboratory values of markers and parameters used to measure severity of infection also. Prealbumin and crp are significant markers for hospital stay (p < 0.01). Prealbumin also found to be a sensitive indicator of nutritional status (p < 0.001).

Interpretation and Conclusion

Prospective analysis indicates prealbumin and crp are effective markers for determining severity of infection, treatment efficacy and hospital stay. Prealbumin is also sensitive marker for nutritional status. Duration of antibiotic usage, intensive unit care, use of nutritional supplements becomes more rationale. Markers also make treatment cost effective and help protecting patients from side effects of excess drug usage.  相似文献   
97.
Cumulative T-cell receptor signal strength and ensuing T-cell responses are affected by both antigen affinity and antigen dose. Here we examined the distinct contributions of these parameters to CD4 T-cell differentiation during infection. We found that high antigen affinity positively correlates with T helper (Th)1 differentiation at both high and low doses of antigen. In contrast, follicular helper T cell (TFH) effectors are generated after priming with high, intermediate, and low affinity ligand. Unexpectedly, memory T cells generated after priming with very low affinity antigen remain impaired in their ability to generate secondary Th1 effectors, despite being recalled with high affinity antigen. These data challenge the view that only strongly stimulated CD4 T cells are capable of differentiating into the TFH and memory T-cell compartments and reveal that differential strength of stimulation during primary T-cell activation imprints unique and long lasting T-cell differentiation programs.Following infection, T-cell receptor (TCR) interactions with foreign peptide/MHC (pMHC) drive the rapid clonal expansion and differentiation of T cells into distinct effector subsets specialized against different classes of microbes. An early bifurcation in CD4 T-cell responses results in the generation of T helper (Th)1 effectors, which regulate innate cell microbicidal function and follicular helper T (TFH) cells, which migrate to B-cell follicles to regulate germinal center (GC) responses and antimicrobial antibody production (1). After pathogen is cleared, T cells undergo a contraction phase during which the majority of effectors die by apoptosis, leaving behind a population of long-lived memory cells to provide protection upon subsequent reinfection. The decision to differentiate into Th1 and TFH lineages appears to occur very early in the immune response (2, 3). Initial T-cell priming by dendritic cells (DCs) is sufficient to induce fate-committed Th1 and TFH cells as early as 3 d after infection, whereas maintenance and further expansion of the TFH compartment depends on T-cell interactions with B cells (2). Similarly, memory T-cell differentiation occurs very early after infection and is critically dependent on B-cell interactions for optimal priming (4, 5). Importantly, CD4 T-cell differentiation is coupled to division, and unlike CD8 T-cell differentiation, requires constant antigen recognition (6, 7).Although the strength of TCR–pMHC interactions has been shown to directly modulate T-cell expansion and clonal dominance within the Th cell compartment (8, 9), how this influences CD4 T-cell fate is not well understood. Cumulative TCR signaling can be influenced by both antigen affinity and antigen dose (10). In terms of proliferation, higher antigen dose can compensate for lower antigen affinity to some extent, but several reports have shown independent effects on T-cell responses both in vitro and in vivo (1012). These data indicate that antigen affinity and antigen dose may promote qualitatively distinct TCR signals. Recently, modulation of the overall TCR signal by varying either TCR affinity or antigen dose was shown to influence the pattern of effector T-cell differentiation, with higher affinity ligands or higher antigen dose promoting TFH generation (1315). However, another study examining high and low avidity CD4 T-cell responses during viral infection found significant differences in Th1 but not TFH generation (16). Sustained TCR–pMHC interactions have also been shown to promote memory T-cell differentiation, which is associated with increased TCR avidity (17, 18). These studies, however, have focused on the development of the Th1 memory compartment, which is phenotypically and functionally distinct from the TFH memory compartment (19, 20). Thus, although strong TCR signals resulting from high antigen affinity or high antigen dose can clearly affect the extent and quality of T-cell differentiation, whether or not T cells can discriminate these signals, and how this contributes to T-cell differentiation during infection, has not been determined.To address this question, we infected mice with varying concentrations of Listeria expressing either high or low affinity antigens for the TCR. By normalizing the degree of proliferation induced by high and low affinity antigens we were able to discern distinct influences of antigen affinity and antigen dose on Th cell differentiation. We observed a strong positive correlation between antigen affinity and Th1 differentiation that occurs early and is dose independent. Importantly, high antigen dose does not compensate for the low efficiency of Th1 differentiation induced by low affinity antigen. In contrast, early TFH effector generation was observed after priming with high, intermediate, and low affinity antigen, but was not maintained at later time points under conditions of low antigen dose. In addition, we found that T cells activated by either high or low affinity antigen are equally capable of memory T-cell differentiation. Surprisingly, memory T cells generated by either low antigen affinity or low antigen dose maintained their biased effector lineages following recall activation with high affinity antigen. These data indicate that differential strength of stimulation during primary T-cell activation can imprint unique and long lasting T-cell differentiation programs.  相似文献   
98.
Bone stock during knee reimplantation for infection is compromised and may contribute to intraoperative fracture. This study aims to describe the prevalence of said fractures. A retrospective review was performed of patients who underwent a staged TKA reimplantation for a periprosthetic infection. Patients who sustained an intraoperative fracture were analyzed. The fracture timing, location, and treatment were recorded. Fracture healing, component stability, and need for re-revision were noted. Between 1990 and 2010, 894 reimplantations were performed. Twenty-three fractures occurred in 21 patients (2.3%) with mean follow-up of 56 months (range: 4–122). Thirteen fractures occurred in femora, 7 in tibiae, and 3 in patellae. Four occurred during resection, while 19 occurred during reimplantation. Observation and wires/cables were the most common treatments utilized. At final follow-up, 91% of fractures demonstrated union and 75% of patients demonstrated stable components. Eight patients (38%) required a revision, the majority of which were performed for re-infection.  相似文献   
99.
Restoring the bladder glycosaminoglycans layer has recently been introduced as prophylactic treatment for recurrent urinary tract infections. Herein, we analyze the latest main clinical and experimental studies to support this therapeutic option. An electronic research was carried out in the most common databases in order to identify any published studies. Retrieved studies were categorized as experimental or clinical according to their setting. For the clinical studies, the evidence level was assigned. A total of 13 laboratory studies showed how bladder glycosaminoglycans instillations act: attenuation of the inflammation process, reduction of bladder contraction amplitude and frequency, reduction of epithelium damage, and lower bacterial growth in urine and tissue samples. Likewise, two randomized clinical trials with grade 2 evidence level and two case series with grade 4 evidence level reported glycosaminoglycans as an alternative to reduce episodes and to prolong recurrence time in patients with recurrent urinary tract infections. At least 12 months of follow up was completed. No serious adverse events were reported. Compared with a placebo, in one randomized study a significantly higher maximum cystometric capacity was obtained, whereas in the other study a significant increase in quality of life scores was reported too. An improvement in the urinary symptoms score was reported by the two randomized trials. Although the clinical use of glycosaminoglycans replacement therapy for recurrent urinary tract infections is supported by a small number of clinical studies with different evidence levels, the laboratory studies show that glycosaminoglycans could have a protective role against inflammatory factors, supporting the idea “to restore the glycosaminoglycans bladder layer to prevent chronic disease course”.  相似文献   
100.
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