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991.
Phenotypic analyses of antibiotic and metal resistance of a collection of 130 strains of Pseudomonas aeruginosa from various outdoor (i.e. soil, water, animals) and hospital (environment, patients, individuals with cystic fibrosis) settings were performed. Resistance was scored according to the origin of the strains and their likely exposure to antibiotics and chemicals. Most of the 76 outdoor strains showed a wild-type antibiotic resistance phenotype, i.e. resistance to minocycline and trimethoprim–sulfamethoxazole. Sixty percent of hospital strains showed a multiresistance phenotype (from 3 to 16 antibiotics) and confirmed that frequent exposure to antibiotics favored selection and maintenance of antibiotic resistance in P. aeruginosa. Twelve percent of outdoor strains naturally exposed to antiseptics and hydrocarbons showed significant resistance profiles, suggesting that chemical contaminants could contribute to selection of antibiotic resistance. For metal resistance, outdoor strains were more frequently resistant to zinc and cadmium, whereas hospital strains were more frequently resistant to mercury and copper. Differences in metal resistance between the 130 strains investigated were not related to previously characterized processes such as those implicating czcA, involved in cadmium, zinc, and cobalt resistance, or copA and copB, involved in copper resistance. Regulatory or new processes were likely to have contributed to the observed variations. Strains showing strong resistance to antibiotics were the least resistant to metals, and inversely. The lack of significant correlations between antibiotic and metal resistance suggests involvement of distinct processes that are rarely co-selected. The effects of the P. aeruginosa collection size and multi-factorial selective pressure on data sets are discussed.  相似文献   
992.

Background

The aim of this study was to examine the scientific evidence on clinical effectiveness and safety used in health technology assessments (HTAs) of high-risk medical devices (MDs) in Europe.

Methods

We applied a systematic approach to identify European institutions involved in HTA and to select reports assessing MDs considered high-risk according to the definition in the new German health care regulation 4137h. Reports published between 2010 and 2015 were considered in our subsequent analysis. We used a structured tool based on widely accepted methodologic principles from Drummond’s framework to extract key information on the clinical evidence considered in the reports.

Results

Out of 1376 identified reports, 93 were eligible for analysis. All reports based their assessment primarily on direct evidence, in most cases (68%) identified through an independent systematic literature search. In more than half the identified studies considered in the reports, clinical evidence for demonstration of effectiveness and safety was of moderate or low quality. Even when systematic reviews and randomized controlled trials were available for assessment, most studies showed an unclear or high risk of bias.

Conclusions

This study confirms that the quality of scientific evidence used in HTA of high-risk MDs is low and therefore the use of evidence needs improvement. The European Commission recently updated the regulation on MDs but mainly focused on the safety of materials and the CE (Conformité Européene [European Conformity]) mark. Our results show that additional changes are necessary, specifically with regard to the marketing authorization process of MDs, with stricter quality requirements based on methodologically robust trials, possibly in combination with other evidence sources.  相似文献   
993.
994.
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996.
Tension pneumomediastinum after severe vomiting in a 21-year-old female.   总被引:1,自引:0,他引:1  
A 21-year-old female with chronic membranoproliferative nephritis was admitted for suspected esophageal disruption and asthma after severe, prolonged vomiting. At the time of admission she presented with dyspnea, tachypnea, arterial hypotension and tachycardia. Physical examination showed discrete signs of ectopic air at the neck and distended cervical veins. CT-scan of the chest showed severe mediastinal emphysema with compression of the right atrium. After cervical mediastinotomy the cardiorespiratory parameters normalized immediately. Esophagoscopy showed multiple longitudinal mucosal tears between 25 and 45 cm; fluoroscopically, there was no leakage of contrast medium. Following conservative treatment the patient recovered completely and was discharged on day 8.  相似文献   
997.
998.
INTRODUCTION: A torn labial frenum is widely regarded as pathognomonic of abuse. METHODS: We systematically reviewed the evidence for this, and to define other intra-oral injuries found in physical abuse. Nine studies documented abusive torn labial frena in 27 children and 24 [corrected] were fatally abused: 22 were less than 5 years old. Only a direct blow to the face was substantiated as a mechanism of injury. RESULTS: Two studies noted accidentally torn labial frena, both from intubation. Abusive intra-oral injuries were widely distributed to the lips, gums, tongue and palate and included fractures, intrusion and extraction of the dentition, bites and contusions. CONCLUSIONS: Current literature does not support the diagnosis of abuse based on a torn labial frenum in isolation. The intra-oral hard and soft tissue should be examined in all suspected abuse cases, and a dental opinion sought where abnormalities are found.  相似文献   
999.
1000.

Purpose

To evaluate the effect of image guided radiotherapy with stereotactic ultrasound BAT (B-mode acquisition and targeting system) on rectal toxicity in conformal radiotherapy of prostate cancer.

Patients and Methods

42 sequential patients with prostate cancer undergoing radiotherapy before and after the introduction of BAT were included. Planning computed tomography (CT) was performed with empty rectum and moderately filled bladder. The planning target volume (PTV) included the prostate and seminal vesicles with a safety margin of 1.5 cm in anterior and lateral direction. In posterior direction the anterior 1/3 of the rectum circumference were included. Total dose was 66 Gy and a boost of 4 Gy excluding the seminal vesicles. 22 patients (BAT group) were treated with daily stereotactic ultrasound positioning, for the other 20 patients (NoBAT group) an EPID (electronic portal imaging device) was performed once a week. Acute and late genito-urinary (GU) and rectal toxicity and PSA values were evaluated after 1.5, 3, 6, 9 and 12 months. The total median follow up of toxicity was 3 years in the BAT group and 4 years in the NoBAT group.

Results

In the NoBAT group significant more rectal toxicity occurred, while in GU toxicity no difference was seen. Two patients in the NoBAT group showed late rectal toxicity grade 3, no toxicity > grade 2 occurred in the BAT group. There was no significant difference in PSA reduction between the groups.

Conclusion

Without BAT significant more acute and a trend to more late rectal toxicity was found. With regard to dose escalation this aspect is currently evaluated with a larger number of patients using intensity-modulated radiotherapy (IMRT).  相似文献   
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