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OBJECTIVE: To determine the natural history of colonization with vancomycin-resistant enterococci (VRE), methicillin-resistant Staphylococcus aureus (MRSA), and resistant gram-negative bacilli among long-term-care facility (LTCF) residents. DESIGN: Observational cohort study. SETTING: A 355-bed LTCF with a ventilator unit and a subacute unit. PARTICIPANTS: Residents with colonization or infection with VRE, MRSA, or resistant gram-negative bacilli housed at the LTCF between December 1, 1999, and February 29, 2000. METHODS: Cultures of clinical and surveillance sites were performed at regular intervals. Charts were reviewed for clinical characteristics associated with clearance of colonization. Kaplan-Meier curves were constructed to analyze the number of days to clearance of colonization. RESULTS: Forty-nine residents had 65 episodes of colonization (27 VRE, 30 MRSA, and 8 resistant gram-negative bacilli). Eighteen (28%) of the episodes cleared. The clearance rate was 2.7 episodes per 1,000 person-days. Clearance occurred significantly more often with resistant gram-negative bacilli colonization compared with VRE or MRSA colonization (6 [75%] vs 12 [21%]; P = .007; relative risk, 4.17; 95% confidence interval, 1.26 to 11.8). There was a trend toward longer use of antimicrobial agents among residents with persistent colonization. Infections occurred most frequently with MRSA. The urinary tract was the most common site of infection. CONCLUSION: Among LTCF residents, colonization with resistant gram-negative bacilli is four times more likely to clear than colonization with VRE or MRSA. Performance of surveillance cultures at regular intervals may reduce the need for contact precautions for LTCF residents with resistant gram-negative bacilli colonization.  相似文献   
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Objective: To determine the effects of a total laryngectomy on the swallow and subsequent quality of life in head and neck cancer patients. Design: Cross‐sectional single centre cohort study. Setting: Head and Neck Oncology Unit, Tertiary Referral Unit. Patients: Sixty‐two patients who underwent total laryngectomy at our centre participated in the study. Methods: Subjects were stratified by age, sex, tumour stage, other procedures such as myotomy and nerve re‐implantation. Pharyngectomy, glossectomy, flap reconstruction, neck dissection and previous radio‐ and chemotherapy were also assessed to see if they affected swallow and subsequent quality of life. Main outcome was measured using the MD Anderson Dysphagia Inventory questionnaire. Results: Responses were received from 46 males and 16 females (response rate of 80.5%) with a mean age of 64.7 years (SD 9.4). Median follow‐up in patients was 90 months (range 1–276). The mean MD Anderson Dysphagia Inventory total score in our series of patients was 77.7 (SD 16.6). MD Anderson Dysphagia Inventory global score was 79.4 (SD 22.6), Emotional score was 77.7 (SD 17.8), Functional score 81.3 (SD 15.9) and Physical score was 74.1(SD 18). Statistically significant differences were seen between the emotional scores of glossectomised and non‐glossectomised patients (Mann Whitney, P = 0.04). No significant correlation was seen between the subscale scores and the remaining treatment variables such as age, gender, site, tumour stage, myotomy, nerve implantation, radiotherapy, reconstruction and major complications. Conclusion: This questionnaire study is the largest of its type to assess the swallow of patients who have undergone laryngectomy at a single centre. The overall result confirmed that most patients had a subjectively good swallow. Only glossectomy and the method of PE segment closure were shown to significantly affect swallowing outcomes following surgery. We recommend further work especially prospective studies pre and post surgery using this or similarly validated instruments to fully assess swallow in the laryngectomy population.  相似文献   
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Rabbits treated with benzo(a)pyrene developed cardiac arrhythmias when exposed by inhalation to 8100 ppm trichloroethylene or 15000 ppm halothane to a greater extent and at lower doses of epinephrine challenge than did controls. Benzo(a)pyrene and 3-methylcholanthrene both increased the metabolism of trichloroethylene, but 3-methylcholanthrene did not increase its cardiotoxic effect. The basis of the arrythmogenic action of benzo(a)pyrene appears to be unrelated to its ability to induce xenobiotic metabolism.  相似文献   
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Acute transverse myelitis (ATM) is a neurologic condition that presents with bilateral lower extremity weakness and sensory loss associated with bowel and bladder dysfunction. Whereas the time of onset may be hours to days, the time to either partial or complete recovery may require months. The etiology is varied and may be idiopathic. Laboratory and radiographic evaluation may be nonrevealing. Corticosteriods have been used for treatment, but their efficacy is controversial. As illustrated by this case report, the essential aspect of the initial management of ATM is the elimination of potentially treatable causes.  相似文献   
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To study the effects of suture material, calibre and tension on the end-to-end oesophageal anastomosis, the cervical oesophagus of the rat was resected for 2.5 mm, 7.5 mm and 12.5 mm respectively in three groups of 60 rats each. End-to-end anastomosis was performed with either 6/0 silk, 6/0 polypropylene or 9/0 polypropylene sutures. There was no postoperative leakage. Mortality was mainly due to hair bolus obstruction at the site of anastomosis. There was no difference in mortality and anastomotic stenosis between groups with different resection lengths. Within each group, however, mortality and anastomotic stenosis were significantly higher in the subgroup of rats with 6/0 silk suture than that in the subgroup with 6/0 polypropylene sutures, which also had significantly higher mortality and anastomotic stenosis than the subgroup with 9/0 polypropylene sutures. Histological examination of the stenosed anastomosis showed disruption of muscle layers and submucosal thickening. It is concluded that the use of fine calibre sutures of biologically inert material would be preferred for the end-to-end anastomosis of the oesophagus.  相似文献   
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