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121.
Total joint replacement has greatly increased over the last decades and so have endoprothesis-associated pathologies. European studies have shown a 10-year durability varying from 88 % to 95?%. By means of histopathology different pathogenetic synovial-like interface membrane (SLIM) patterns that lead to reduction of implant durability can be discerned, such as periprosthetic particles, bacterial infections and arthrofibrosis. Subsequently, SLIM types have been determined in a revised consensus classification including particle-induced type (type I) so-called non-septic loosening, infection type (type II) so-called septic loosening, combination type (type III) of bacterial and particle-induced types, indifferent type with mechanical and functional disorders (type IV), osseus pathologies (type V), arthrofibrotic type (type VI, endoprosthesis-associated arthrofibrosis) and allergic/immunological/toxic reactions to prosthesis material (type VII). Particles are characterized histopathologically according to the Krenn particle algorithm. In cases of severe lymphocyte/macrophage infiltration, necrosis, abrasion particle detection and granuloma formation, a toxic or allergic reaction to implant material should be considered. As a direct abrasion particle-induced toxicity cannot be differentiated from a particle-induced allergic type VII reaction to implant material, the histopathological diagnosis of toxic reaction to implant material or allergic reaction to implant material should be made with caution and only in association with immunological, allergic and clinical data. It is recommended that tissue samples should be arthroscopically taken from different regions: close to the prosthesis, distant from the prosthesis and from bone tissue. The pathologist should be given information concerning clinical, allergological and microbiological data.  相似文献   
122.
Molecular genotyping studies often focus on clustered tuberculosis and recent transmission. Less attention has been paid to non-clustered tuberculosis. However, non-clustered cases also contribute significantly to the tuberculosis burden, especially in low-incidence countries. The objective of this study is to characterize non-clustered tuberculosis cases in Denmark and point out potential implications for tuberculosis control. The study is based on nationwide IS6110-RFLP genotyping of tuberculosis cases from 1992 through 2004, corresponding to 98% of culture verified cases. Of 3988 cases, 45% were non-clustered. Both Danes and immigrants had a peak incidence of non-clustered tuberculosis at older ages, 80-89 years (4.3 cases/10(5) population/year) and 60-69 years (28.8 cases/10(5) population/year), respectively. In addition, immigrants had a peak at 20-29 years (43.2?cases/10(5) inhabitants/year). In Danes, the incidence of non-clustered tuberculosis decreased during the study period and was predominantly found in elderly persons, presumably reactivating infection acquired during 1910-40, when tuberculosis incidence was high. In immigrants, the incidence was high at all ages, presumably reflecting reactivation of imported infections. In the future, the number of non-clustered tuberculosis cases will decrease, as older Danes die, and as time since primary infection increases for immigrants residing in Denmark. TB control should include focus on non-clustered cases.  相似文献   
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Background

Previously active in the mid-1990s, the Canadian Airway Focus Group (CAFG) studied the unanticipated difficult airway and made recommendations on management in a 1998 publication. The CAFG has since reconvened to examine more recent scientific literature on airway management. The Focus Group’s mandate for this article was to arrive at updated practice recommendations for management of the unconscious/induced patient in whom difficult or failed tracheal intubation is encountered.

Methods

Nineteen clinicians with backgrounds in anesthesia, emergency medicine, and intensive care joined this iteration of the CAFG. Each member was assigned topics and conducted reviews of Medline, EMBASE, and Cochrane databases. Results were presented and discussed during multiple teleconferences and two face-to-face meetings. When appropriate, evidence- or consensus-based recommendations were made together with assigned levels of evidence modelled after previously published criteria.

Conclusions

The clinician must be aware of the potential for harm to the patient that can occur with multiple attempts at tracheal intubation. This likelihood can be minimized by moving early from an unsuccessful primary intubation technique to an alternative “Plan B” technique if oxygenation by face mask or ventilation using a supraglottic device is non-problematic. Irrespective of the technique(s) used, failure to achieve successful tracheal intubation in a maximum of three attempts defines failed tracheal intubation and signals the need to engage an exit strategy. Failure to oxygenate by face mask or supraglottic device ventilation occurring in conjunction with failed tracheal intubation defines a failed oxygenation, “cannot intubate, cannot oxygenate” situation. Cricothyrotomy must then be undertaken without delay, although if not already tried, an expedited and concurrent attempt can be made to place a supraglottic device.  相似文献   
126.

Background

Does below-knee symptomatic muscular (gastrocnemius or soleus) vein thrombosis (MVT) warrant investigation and treatment in post-operative orthopaedic patients? We performed a literature search and evaluated the evidence looking for guidance regarding this question.

Materials and methods

We performed a literature search with the use of PubMed, Medline and Google Scholar from 1950 to September 2011. Search terms included “muscular vein thrombosis” (MVT) and “isolated gastrocnemius or soleus vein thrombosis” (IGSVT). We reviewed the eight level II studies relevant to our search, only one of which was in a specific orthopaedic population.

Results

Studies looking at the rates of progression of isolated MVT have shown conflicting results. There is also a lack of consensus between studies that compare progression amongst groups with or without anticoagulant treatment. The majority of the studies do not distinguish between medical, surgical or orthopaedic patients.

Conclusions

We cannot confidently recommend commencement of anticoagulation treatment upon identification of MVT in post-operative orthopaedic patients. We can only suggest that, once MVT is diagnosed, the patient should undergo serial ultrasound scan (USS) duplex scans, and if propagation is identified, then treatment may be deemed beneficial.Level of evidence: III (review of non-randomized controlled cohort/follow-up studies).  相似文献   
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Brain water self diffusion was investigated by magnetic resonance scanning in 7 patients fulfilling conventional diagnostic criteria for pseudotumour cerebri. Quantitative diffusion measurements were obtained using single spin echo pulse sequences with pulsed magnetic field gradients of different magnitude. In all patients the diffusion images showed an increased diffusion in various brain regions when compared with the diffusion coefficients for corresponding regions in healthy subjects. In 3 pseudotumour patients the increased self diffusion was localized to the periventricular regions, while 4 patients had increased diffusion in the whole brain. The findings indicate the presence of increased brain water content both intra- and extracellularly suggesting that patients with pseudotumour have two defects of pathogenetical significance: intracellular water accumulation and increased resistance to cerebrospinal fluid (CSF) outflow leading to an interstitial oedema.  相似文献   
130.

Objective

Surveys assessing alcohol use among physicians have most commonly employed the Alcohol Use Disorders Identification Test (AUDIT) or the AUDIT-C, the most common short version of the AUDIT. As with other screeners, prevalence estimation is dependent on the accuracy of the test as well as choice of the cutoff value. The aim of the current study is to derive more precise prevalence estimates of alcohol problems in physicians by correcting for false-positive and false-negative results.

Method

In the context of a survey, the AUDIT was sent out via email or standard postal service to all 2484 physicians in Salzburg, Austria. A total of 456 physicians participated. A published correction formula was used to estimate the real prevalence of alcohol use problems.

Results

Applying a cutoff of 5 points for the AUDIT-C, 15.7% of female and 37.7% of male physicians screened positive. Use of a correction based on general population data and the sensitivity and specificity of the AUDIT-C resulted in much lower prevalence rates: 4.0% for female and 9.5% for male physicians. Using the full AUDIT, 19.6% of the female physicians and 48% of the male physicians were screened positive. Using the correction, the estimated prevalence rates for females and males were 6.3% and 15.5%, respectively.

Conclusions

Our findings demonstrate that uncorrected screening results may markedly overestimate the prevalence of physicians drinking problems.  相似文献   
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