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101.

Background

We are presenting our experience in the use of locking compression plate (LCP) after juxta-articular oncological resections in addition to its use in pathologic fracture.

Methods

A retrospective audit of skeletal reconstruction using LCP in 25 cases of long bone tumors was performed from 2008 to 2010. Reconstruction following limb salvage surgery was done in 17 patients and internal fixation of pathological fracture was done in 8 patients. All patients were available for > 12 months of follow-up, and thus assessed for union at the resected ends.

Results

There were 8 males and 17 females in the study. The average age at the time of surgery was 30 years (range, 9 to 66 years). The minimum follow-up was 12 months (range, 12 to 32 months). All patients except three went on to heal successfully. Complications occurred in those three patients: wound infection in one, nonunion in another, and periprosthetic fracture in the other patient. In the remaining patients, union was achieved at an average of 6.5 months after reconstruction in curative resection and 4.75 months after fixation of pathological fractures.

Conclusions

Joint sparing limb salvage surgery was made successfully possible after sekeletal reconstruction with LCP. Its use was also quite effective in pathological fractures with poor bone quality. Use of locking plates for musculoskeletal oncological reconstruction resulted in a good and predictable rate of union.  相似文献   
102.
M5 muscarinic acetylcholine receptors expressed on ventral tegmental dopamine (DA) neurons are needed for opioid activation of DA outputs. Here, the M5 receptor gene was bilaterally transfected into neurons in the ventral tegmental area (VTA) or the adjacent rostromedial tegmental nucleus (RMTg) in mice by means of a Herpes simplex viral vector (HSV) to increase the effect of endogenous acetylcholine. Three days after HSV‐M5 gene infusion in VTA sites, morphine‐induced locomotion more than doubled at two doses, while saline‐induced locomotion was unaffected. When the HSV‐M5 gene was infused into the adjacent RMTg, morphine‐induced locomotion was strongly inhibited. The sharp boundary between these opposing effects was found where tyrosine hydroxylase (TH) and cholinesterase labelling decreases (?4.00 mm posterior to bregma). The same HSV‐M5 gene transfections in M5 knockout mice induced even stronger inhibitory behavioural effects in RMTg but more variability in VTA sites due to stereotypy. The VTA sites where HSV‐M5 increased morphine‐induced locomotion receive direct inputs from many RMTg GAD‐positive neurons, and from pontine ChAT‐positive neurons, as shown by cholera‐toxin B retrograde tracing. Therefore, morphine‐induced locomotion was decreased by M5 receptor gene expression in RMTg GABA neurons that directly inhibit VTA DA neurons. Conversely, enhancing M5 receptor gene expression on VTA DA neurons increased morphine‐induced locomotion via cholinergic inputs.  相似文献   
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Background

The unsuccessful treatment of prosthetic joint infection (PJI) with two-stage revision leads to infection recurrence. The objectives of the study were to assess the clinical and demographic characteristics of patients with polymicrobial PJI, and to evaluate the role of the microbial profile involved in PJI in the risk of infection recurrence after the first step of two-stage revision surgery.

Materials and methods

A retrospective analysis of 189 cases of culture-positive PJI following total hip replacement over a 5-year period was performed. The demographic characteristics of patients, clinical symptoms, microbiology cultures of intraoperative biopsies, laboratory values of C-reactive protein (CRP), white blood cell count and erythrocyte sedimentation rate were analyzed. Patients were divided into two groups—135 with monomicrobial and 54 with polymicrobial infection.

Results

Of all patients, 68.9 % in the monomicrobial and 83.3 % in the polymicrobial group had a body mass index >25 kg/m2 (p = 0.05). The median CRP values were 5.7 mg/L (IQR 4.0–10.0 mg/L) in the monomicrobial compared to 8.8 mg/L (IQR 5.0–27 mg/L) in the polymicrobial group (p = 0.01). The percentage of successful outcomes was 27.8 % in patients with microbial associations (p < 0.0001). Gram-negative pathogens caused polymicrobial PJI in 61.5 % of cases with infection recurrence (OR 4.4; 95 % CI 1.18–16.37; p = 0.03).

Conclusions

Overweight and obese patients or those with elevated CRP had a greater risk of polymicrobial PJI. They were predisposed to recurrence of infection after the first step of two-stage revision. An unsuccessful outcome was more likely in cases with polymicrobial infection compared to those with monomicrobial infection. In addition, the presence of multidrug-resistant strains of Gram-negative bacteria substantially increased the risk of PJI treatment being unsuccessful.

Level of evidence

Level III, therapeutic study.
  相似文献   
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Context

Twitter is a social media platform on which users post very brief messages that can be rapidly communicated across wide geographical areas and audiences. Many doctors use Twitter for personal as well as professional communications and networking. The #TipsForNewDocs hashtag is used on Twitter to give advice to newly qualified doctors as they commence their careers. This study explores the nature and focus of such advice.

Methods

An analysis of Twitter activity containing the #TipsForNewDocs hashtag was performed using Symplur health care analytics software. Tweets sent during a peak 48‐hour period in 2016 (immediately preceding the first day of work for newly qualified UK doctors) were studied. The geographical locations and professional backgrounds of participants were categorised and the content of tweets was subjected to thematic analysis. During 1 and 2 August 2016, 661 unique #TipsForNewDocs tweets were posted. A total of 621 (94.0%) were posted by people in the UK ; 522 (79.0%) were posted by doctors, and the remainder by allied health care professionals and patients.

Results

The majority of included tweets focused on aspects of professional development, improving personal or professional knowledge, particularly tacit knowledge, and developing ‘know‐how’. These aspects of professional knowledge have previously been described as fundamental to professional education and training. However, a significant subset of tweets focused on accelerating socialisation into the profession, an essential step in joining a professional community. The tweets relating to socialisation were often humorous and colloquial in nature.

Conclusions

Despite their brief and often jocular nature, #TipsForNewDocs tweets provided meaningful advice for newcomers to the profession, often focusing on tacit learning and professional socialisation. Hashtag‐driven enquiries can be a valuable and time‐efficient way of accessing and sharing tacitly held knowledge. Social media content analysis can provide valuable insights into key educational issues.
  相似文献   
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