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Effective surveillance of antimicrobial-resistant bacteria is important for developing rational empiric therapy guidelines and for guiding public health efforts to control and prevent the spread of infective agents. Surveillance must include a timely and thorough review of the test results generated in clinical microbiology laboratories because this data serves as the core of surveillance activities. Besides ensuring data accuracy and optimizing detection of emerging resistance, the role of clinical microbiology also includes supporting the production of informative surveillance reports, providing laboratory resources for outbreak investigations, and monitoring the performance of commonly used susceptibility testing methods. Once the accuracy of susceptibility results has been validated, the data are used by public health agencies and professional societies to monitor resistance trends on a local, state, national, and international level. This information is also used to develop policies for prudent antimicrobial use locally and nationally. 相似文献
994.
G C Mead 《International journal of food microbiology》1992,17(2):135-143
The clostridia are a group of anaerobic bacteria that vary considerably in their biochemical and physiological properties. Not surprisingly, attempts to develop a single isolation medium for all species that occur in foods have not been entirely successful, and the problem is compounded by the need to recover both vegetative cells and spores, some of the latter being unable to germinate without heat activation. Most available isolation media, except some of those used in the dairy industry, include sulphite and an appropriate iron salt, so that blackening due to sulphite reduction can serve as a differential test for clostridia. The limitations of this test in solid agar media are discussed and some advantages described in relation to its use in liquid media for Most Probable Number determinations. A medium favoured for the purpose is the Differential Reinforced Clostridial Medium of Gibbs and Freame (1965). An unresolved issue is whether or not special precautions are needed to exclude oxygen during food sample preparation and dilution, preparation of media, and in conditions used for anaerobic incubation. Although such stringency may be required for maximum recovery of sub-lethally damaged cells or spores, practical constraints in food control laboratories necessitate use of relatively simple procedures for detecting clostridia routinely. 相似文献
995.
996.
Three discrete multivariate analysis techniques were used to assess the accuracy of land use/land cover classifications generated from remotely sensed data. Error matrices or contingency tables were analyzed using these techniques and the results reported. The first technique is a normalization procedure using an "iterative proportional fitting" algorithm that allows for direct comparison of Corresponding cell values in different matrices irregardless of sample size. The second technique provides a method of testing for significant differences between error matrices that vary by only a single variable or factor. The third technique allows for multivariable comparisons to be made between matrices. Each technique is implemented through the use of a computer program. 相似文献
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998.
Used standardized questionnaires to compare psychosocial functioning of 116 children and adolescents (9 to 18 years) and 73 adults (18 to 38 years) operated on for hypospadias, a congenital penile anomaly, with that of 88 and 50 age-matched comparison males, respectively, treated for an inguinal hernia. The relationships of coping with penile appearance, subject age, severity of hypospadias, number of operations, age at final surgery, and type of surgical procedure with psychosocial functioning were also investigated. Hypospadias patients did not exhibit a poorer psychosocial functioning and no significant relationships of various medical characteristics with psychosocial functioning could be discerned. Genital/body perception of hypospadias patients ages 9 to 18 years correlated positively with psychosocial functioning, albeit with low values. These findings are important for psychologists and specialists in the counseling process of hypospadias patients and their parents. 相似文献
999.
OBJECTIVE: To analyze the association between arachnoid cysts and subdural hygromas. METHODS: We reviewed five cases of arachnoid cysts that ruptured, producing acute subdural hygromas. The surgical management and diagnostic methods used are assessed. RESULTS: Five male patients ranging in age from 6 to 25 years sustained the rupture of arachnoid cysts, which produced acute subdural hygromas. Four of the patients had incurred blunt head trauma. All patients presented with symptoms referable to intracranial hypertension. The pathognomonic features of a middle fossa arachnoid cyst (MFAC) were noted on the computed tomographic scans and/or magnetic resonance images of each patient. The hygroma exerted mass effect on the ipsilateral hemisphere and was noted to be under significant pressure at the time of surgical intervention in each case. Two of the five cases are unique in the literature. In one, a coexisting quadrigeminal cyst ruptured, producing a subdural hygroma ipsilateral to the MFAC and dilating the basal cisterns. In the other, the MFAC ruptured into the basal cisterns as well as into the subdural space. The MFAC in each of the remaining three patients ruptured into the subdural space alone. All patients were treated with drainage of the subdural space. In the two patients in whom the basal cisterns were involved, both the hygromas and the MFACs failed to change significantly in size. The hygromas resolved completely and the MFACs decreased in size considerably in the three patients without cisternal involvement. CONCLUSION: The rupture of an arachnoid cyst can produce a subdural hygroma and intracranial hypertension. The latter mandates emergent drainage of the subdural space. In patients in whom the basal cisterns are not dilated by cyst rupture, both the MFACs and hygromas resolve after subdural drainage. 相似文献
1000.