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101.
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Juvenile ossifying fibroma (JOF) is a rare fibro-osseous neoplasm, defined as a variant of the ossifying fibroma that arises within the craniofacial bones. Two subgroups, juvenile psammomatoid ossifying fibroma (PsJOF) and juvenile trabecular ossifying fibroma, have been delineated by their histology. PsJOF occurs predominantly in the sinonasal and orbital bones. This work reports on 2 cases of extensive PsJOF in the body of the right mandible as well as reviews the literature regarding the radiographic and histologic features, treatment, and prognosis of PsJOF of the jaws.  相似文献   
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HIV-1 drug resistance monitoring in resource-poor settings is crucial due to limited drug alternatives. Recent reports of the increased prevalence of CXCR4 usage in subtype C infections may have implications for CCR5 antagonists in therapy. We investigated the prevalence of drug resistance mutations and CXCR4 coreceptor utilization of viruses from HIV-1 subtype C-infected children. Fifty-one children with virological failure during highly active antiretroviral therapy (HAART) and 43 HAART-naive children were recruited. Drug resistance genotyping and coreceptor utilization assessment by phenotypic and genotypic methods were performed. At least one significant drug resistance mutation was present in 85.4% of HAART-failing children. Thymidine analogue mutations (TAMs) were detected in 58.5% of HAART-failing children and 39.0% had ≥3 TAMs. CXCR4 (X4) or dual (R5X4)/mixed (R5, X4) (D/M)-tropic viruses were found in 54.3% of HAART-failing and 9.4% of HAART-naive children (p<0.0001); however, the HAART-failing children were significantly older (p<0.0001). In multivariate logistic regression, significant predictors of CXCR4 usage included antiretroviral treatment, older age, and lower percent CD4(+) T cell counts. The majority of genotypic prediction tools had low sensitivity (≤65.0%) and high specificity (≥87.5%) for predicting CXCR4 usage. Extensive drug resistance, including the high percentage of TAMs found, may compromise future drug choices for children, highlighting the need for improved treatment monitoring and adherence counseling. Additionally, the increased prevalence of X4/D/M viruses in HAART-failing children suggests limited use of CCR5 antagonists in salvage therapy. Enhanced genotypic prediction tools are needed as current tools are not sensitive enough for predicting CXCR4 usage.  相似文献   
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目的 探讨肿瘤坏死因子(TNF)-α拮抗剂对炎性关节病患者乙型肝炎病毒(HBV)再激活及肝功能的影响.方法 活动期类风湿关节炎(RA)及强直性脊柱炎(AS)患者根据HBV血清学指标分组,动态随访TNF-α拮抗剂治疗后HBV再激活及肝功能情况.多组间连续变量比较采用Kruskal-Wallis 非参数检验,分类变量比较采用x2检验或Fisher精确概率法.结果 50例患者完成随访,随访时间3~23个月.治疗后转氨酶水平慢性HBV感染组患者[11例,天冬氨酸转氨酶(AST):(36+18) U/L,丙氨酸转氨酶(ALT):(44±46)U/L]显著高于既往HBV感染组[16例,AST:(22±6)U/L,ALT:( 17±9) U/L]和无HBV感染组[23例,AST:( 19:±6) U/L,ALT:(15:±9) U/L](AST:x2=11.161,P<0.01;ALT:x2=8.038,P<0.01).1例基线HBV-DNA升高的AS患者治疗前加用拉米夫定,4个月后HBV-DNA降至接近正常;余10例基线HBV-DNA阴性的慢性HBV感染患者中,1例治疗后发生HBV再激活伴转氨酶升高,1例仅有转氨酶升高而HBV-DNA持续阴性,且停药后转氨酶自行回复正常,考虑为药物的肝损害.既往HBV感染组及无感染组患者治疗后未出现乙型肝炎表面抗原(HBsAg)转阳.结论 炎性关节病患者使用TNF-α拮抗剂前须筛查HBV感染及肝功能情况,治疗期间需密切监测肝功能及HBV再激活情况,基线HBV-DNA阳性(尤其>105 copies/ml)或经济能力允许的合并慢性HBV感染的患者应在治疗前开始预防性抗病毒治疗.  相似文献   
108.

Background

The fields of surgery and trauma care have largely been neglected in the global health discussion. As a result the idea that surgery is not safe or cost effective in resource-limited settings has gone unchallenged. The SIGN Online Surgical Database (SOSD) is now one of the largest databases on trauma surgery in low- and middle-income countries (LMIC). We wished to examine infection rates and risk factors for infection after IM nail operations in LMIC using this data.

Methods

The SOSD contained 46,722 IM nail surgeries in 58 different LMIC; 46,113 IM nail operations were included for analysis.

Results

The overall follow-up rate was 23.1 %. The overall infection rate was 1.0 %, 0.7 % for humerus, 0.8 % for femur, and 1.5 % for tibia fractures. If only nails with registered follow-up (n = 10,684) were included in analyses, infection rates were 2.9 % for humerus, 3.2 % for femur, and 6.9 % for tibia fractures. Prophylactic antibiotics reduced the risk of infection by 29 %. Operations for non-union had a doubled risk of infection. Risk of infection was reduced with increasing income level of the country.

Conclusions

The overall infection rates were low, and well within acceptable levels, suggesting that it is safe to do IM nailing in low-income countries. The fact that operations for non-union have twice the risk of infection compared to primary fracture surgery further supports the use of IM nailing as the primary treatment for femur fractures in LMIC.  相似文献   
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We studied the effects of antibiotic prophylaxis, systemically and in bone cement, on the revision rate of cemented total hip arthroplasties (THAs) in data from the Norwegian Arthroplasty Register during the period 1987-2001. To have comparable groups, only THAs performed because of primary osteoarthritis, using cemented implants with documented good results, and high-viscosity cement were included. If systemic antibiotic prophylaxis had been given, only operations with cephalosporin or penicillin were selected. Cox-estimated survival relative revision risks (RR) are presented with adjustment for differences among groups in gender, age, cement brand, type of systemic antibiotic prophylaxis, type of prosthesis, type of operating room, and duration of the operation. Of 22,170 THAs studied, 696 THAs (3.1%) were revised, 440 (2.0%) for aseptic loosening and 102 (0.5%) for deep infection. We found the lowest risk of revision when the antibiotic prophylaxis was given both systemically and in the cement (15,676 THAs). Compared to this combined regime, patients who received antibiotic prophylaxis only systemically (5,960 THAs) had a 1.4 times higher revision rate with all reasons for revision as endpoint (p= 0.001), 1.3 times higher with aseptic loosening (p= 0.02) and 1.8 times higher with infection as the endpoint (p= 0.01). With the combined antibiotic regime, the results were better if antibiotics were given 4 times on the day of surgery (2,194 THAs), as compared to once (1,424 THAs) (p<0.001), twice (2,680 THAs) (p<0.001), or 3 times (5,522 THAs) (p= 0.02). Those who received systemic prophylaxis a single day 1, 2 or 3 times, as compared to 4 times, had a revision rate 1.8-3.5 times higher with all reasons for revision as endpoint, 1.5-3.1 times higher with aseptic loosening, and 2.7-6.8 times higher with infection. When we compared systemic prophylaxis 4 times in 1 day, no further improvement resulted in those given systemic prophylaxis for 2 days (1,928 THAs) or 3 days (717 THAs). In a subset of data including only the Charnley prosthesis, we obtained similar results. This observational study shows that the best results were recorded when antibiotic prophylaxis was given both systemically and in the bone cement, and if the systemic antibiotic was given 4 times on the day of surgery.  相似文献   
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