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1.
Background: The attempts to explain the unpredictability of extent of spinal block provided by plain local anesthetic solutions have resulted in many clinical reports; however, causes of this uncertainty are as yet unknown. Recently, normal values of the human cerebrospinal fluid densities have been studied showing important interindividual variations, especially between females and males. The current study was designed to evaluate as primary endpoint the influence of cerebrospinal fluid density values on the extent of spinal block with plain bupivacaine. The ancillary endpoints were search of factors explaining the interindividual differences in cerebrospinal fluid density values reported and determination of the relation between upper extent and regression of spinal anesthesia.

Methods: Sixty-four consecutive patients undergoing peripheral orthopedic surgery with spinal block were enrolled. Spinal anesthesia was performed in the lateral decubitus position with the operated side upward. Two milliliters of cerebrospinal fluid was sampled before injection of 3 ml plain bupivacaine 0.5%. The patient was immediately turned supine and remained in the horizontal position until the end of the study. Maximal sensory block level and time to sensory regression to L4 were determined for each patient enrolled. Cerebrospinal fluid and bupivacaine densities as well as cerebrospinal proteins, glucose, sodium, and chloride concentrations were measured.

Results: A highly significant correlation between cerebrospinal fluid density and maximal sensory block level was found (P = 0.0004). However, this correlation was poorly predictive (R2 = 0.37). Cerebrospinal fluid density, proteins, and glucose concentrations were significantly higher in men than in women: 1.000567 +/- 0.000091 versus 1.000501 +/- 0.000109 g/ml (P = 0.014), 0.46 +/- 0.18 versus 0.32 +/- 0.13 g/l (P = 0.001), and 3.27 +/- 0.7 versus 2.93 +/- 0.5 mm (P = 0.023), respectively. A highly significant (P = 0.0004) and predictive (R2 = 0.73) inverse correlation was found between maximal upper sensory extent and sensory regression to L4.  相似文献   

2.
Zusammenfassung Die artifizielle Hibernation hemmt und verzögert die Vermehrung und die Ausbreitung von Virus Aujeszky im ZNS. peripher infizierter Kaninchen erheblich. Hierdurch findet die frühere Beobachtung 1, wonach die Dauer der Inkubationsperiode und des Krankheitsverlaufes des M. Aujeszky bei Kaninchen beträchtlich verlängert ist, eine hinreichende Erklärung.  相似文献   
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BackgroundAfter intrauterine growth retardation, many minor neurodevelopmental disorders may occur, especially in the motor skills domain, language and speech development, and cognitive functions.AimThe assessment of language development and impact of postnatal head growth in preschool children born with asymmetrical intrauterine growth retardation.MethodsExaminees were born at term with birth weight below the 10th percentile for gestational age, parity and gender. Mean age at the time of study was six years and four months. The control group was matched according to chronological and gestational age, gender and maternal education with mean age six years and five months. There were 50 children with intrauterine growth retardation and 50 controls, 28 girls and 22 boys in each group. For the assessment of language development Reynell Developmental Language Scale, the Naming test and Mottier test were performed.ResultsThere were statistically significant differences (p < 0.05) in language comprehension, total expressive language (vocabulary, structure, content), naming skills and non-words repetition. Statistically significant positive correlations were found between relative growth of the head [(Actual head circumference ? head circumference at birth)/(Body weight ? birth weight)] and language outcome. Children with neonatal complications had lower results (p < 0.05) in language comprehension and total expressive language.ConclusionIntrauterine growth retardation has a negative impact on language development which is evident in preschool years. Slow postnatal head growth is correlated with poorer language outcome. Neonatal complications were negatively correlated with language comprehension and total expressive language.  相似文献   
5.
Long-term effectiveness and repeated administration of botulinum toxin A are the basis for its use in both neuromuscular disorders and certain painful conditions. Botulinum toxin A has been recently approved for migraine treatment, and its off-label use extends to other craniofacial pain disorders. However, recently it was reported that, after repeated injection, botulinum toxin loses its antinociceptive efficacy in rats. In present study with a similar design, we compared the effects of single and repeated injections of botulinum toxin in formalin-induced orofacial pain. No statistically significant differences were found between single or repeatedly treated animal groups. Our results are in line with the clinical experience and suggest that botulinum toxin can be re-administered in orofacial pain treatment.  相似文献   
6.

Purpose

In prosthetic joint infections (PJIs) of the knee, debridement with implant retention is associated with a high risk of recurrence.

Methods

A single-centre cohort study was performed with extensive analysis of the literature covering 1980–2012.

Results

In 21 patients (mean age 80.4 years, 19 immunosuppressed), in association with 1.5–three months of antibiotic treatment, an attempt was made to salvage the prosthesis by open (11 patients) or arthroscopic (ten patients) debridement. After a mean follow-up of seven years (range four–20 years), patients were in remission in seven cases (33 %). Remission was achieved in 0 % of all methicillin-resistant Staphylococcus aureus (MRSA) infections (zero/three), in 0 % (zero/three) of methicillin-resistant coagulase-negative staphylococcal infections, in 29 % (two/seven) of methicillin-sensitive S. aureus infections and in 75 % (three/four) of infections due to streptococci. The literature review focused on implant preserving approaches yielded 599 cases with an overall success rate of 47 % (284/599) and significantly more remissions in streptococcal vs staphylococcal knee PJIs (43/54 vs 144/324; p < 0.01, odds ratio 4.9, 95 % confidence interval 2.4–10.9).

Conclusions

In addition to established indications for explantation such as implant loosening, sinus tract or methicillin resistance, the decision for debridement and retention of knee PJIs should also depend on the pathogen. Implant preservation is futile with methicillin-resistant staphylococci, but seems to be a valid option for streptococcal PJIs.  相似文献   
7.

Purpose

Empirical broad-spectrum antibiotic treatment for orthopaedic implant infections after surgical lavage is common practice while awaiting microbiological results, but lacks evidence.

Methods

This was a single-centre cohort study from 1996 to 2010 with a follow-up of two years.

Results

We retrieved 342 implant infections and followed them up for a median of 3.5 years (61 recurred, 18 %). Infected implants were arthroplasties (n = 186), different plates, nails or other osteosyntheses. The main pathogens were S. aureus (163, 49 methicillin-resistant) and coagulase-negative staphylococci (60, 45 methicillin-resistant). Median duration of empirical antibiotic coverage after surgical drainage was three days before switching to targeted therapy. Vancomycin was the most frequent initial empirical agent (147), followed by intravenous co-amoxiclav (44). Most empirical antibiotic regimens (269, 79 %) proved sensitive to the causative pathogen, but were too broad in 111 episodes (32 %). Cephalosporins and penicillins were used only in 44 and ten cases, respectively, although they would have covered 59 % of causative pathogens identified later. Multivariate Cox regression analysis showed that neither susceptible antibiotic coverage (compared to non-susceptible; hazard ratio 0.7, 95 % confidence interval 0.4–1.2) nor broad-spectrum use (hazard ratio 1.1, 0.8–1.5) changed remission rates.

Conclusions

Provided that surgical drainage is performed, broad-spectrum antibiotic coverage does not enhance remission of orthopaedic implant infections during the first three days. If empirical agents are prescribed from the first day of infection, narrow-spectrum penicillins or cephalosporins can be considered to avoid unnecessary broad-spectrum antibiotic use.  相似文献   
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OBJECTIVES: The purpose of this investigation was to examine the relationship between psychosocial variables and working conditions, and nurses' coping methods and distress in response to the severe acute respiratory syndrome (SARS) crisis in Canada. PARTICIPANTS AND PROCEDURE: The sample consisted of 333 nurses (315 women, 18 men) who completed an Internet-mediated questionnaire that was posted on the Registered Nurses' Association of Ontario (RNAO) website between March and May 2004. The questionnaire was restricted to respondents who had to authenticate their RNAO membership with a valid username and password before accessing the questionnaire. This served a dual purpose: to ensure that only RNAO nurses completed the questionnaire and thereby safeguarding the generalizability of the findings; and second, to prevent any one nurse from contributing more than once to the overall sample. RESULTS: Correlational analysis yielded several significant relationships between psychosocial variables and working conditions, and the traditional correlates of burnout and stress. Three multiple regression analysis revealed that the model we evolved--including higher levels of vigor, organizational support, and trust in equipment/infection control initiative; and lower levels of contact with SARS patients, and time spent in quarantine--predicted to lower levels of avoidance behavior, emotional exhaustion, and state anger. CONCLUSIONS: By employing models of stress and burnout that combine psychosocial variables and working conditions, researchers can account for significant amounts of variance in outcomes related to burnout. These findings highlight the importance of vigor and perceived organizational support in predicting nurses' symptoms of burnout. For healthcare administrators, this means that a likely strategy for assuaging the negative outcomes of stress should address nurses' psychosocial concerns and the working conditions that they face during novel times of crisis.  相似文献   
10.
Pulmonary inflammatory myofibroblastic tumor encompasses a heterogeneous spectrum of reactive, infectious, and neoplastic entities. It is composed of spindle-shaped myofibroblastic cells in a background of inflammatory cells and collagen fibres. Actinomycosis is a bacterial infection. It infects the lower respiratory tracts by inhalation or aspiration of oropharyngeal or upper gastrointestinal materials. Only eight cases of pulmonary IMT associated with actinomycosis have been reported in the literature so far. This is the ninth case reported.  相似文献   
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