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1.
This study was designed to characterize a collection of 60 enteropathogenic Escherichia coli (EPEC) isolates from diarrheic feces of patients in the Ribeirão Preto metropolitan area regarding different phenotypic and molecular features. We examined antibiotic resistance profiles, occurrence of virulence factors‐encoding genes, intimin subtypes and the correlation of serotypes among typical (tEPEC) and atypical (aEPEC) EPEC isolates. The results demonstrated that atypical EPEC was more heterogeneous than typical EPEC concerning the characteristics investigated and 45.2% do not belong to classical EPEC serogroups. Intimin subtype β was the most frequent among the EPEC isolates (46.7%), being detected in both tEPEC and aEPEC. The majority of aEPEC isolates presented localized adherence‐like (LAL) pattern to HEp‐2 cells, although aEPEC isolates displaying diffuse adherence (DA) or non‐adherent were also detected. High prevalence of antimicrobial resistance was found for ampicillin, cephalothin, sulfonamide and tetracycline. In general, tEPEC isolates were more resistant to the antimicrobials tested than aEPEC isolates.  相似文献   
2.
Enterococcus faecalis (E. faecalis) is a common cause of nosocomial infection in immunocompromised patients. The presence and dissemination of high‐risk clonal complexes, such as CC2, is an ongoing problem in hospitals. The aim of this work was to characterize 24 E. faecalis isolates from ICU patients undergoing selective decontamination of the digestive tract (SDD) by phenotypical (antimicrobial susceptibility) and genotypical (presence of virulence genes, RAPD‐PCR and MLST) methods. Our results showed high prevalence of the ST6 E. faecalis clone (91.6%), especially adapted to the hospital environment, with a multidrug resistance pattern and a multitude of putative virulence genes. In addition, ST179 (4.2%) and ST191 (4.2%) were detected. By RAPD–PCR analysis, the 22 isolates identified as ST6 showed six different DNA patterns, while the two remaining isolates, ST179 and ST191, showed two additional profiles. CC2 is a known clonal complex with high adaptability to hospital environment and worldwide distribution. The high prevalence of the ST6 clone in the studied population could be related to the presence of gentamicin in the SDD mixture since most strains were gentamicin resistant. Consequently, strict surveillance should be applied for rapid detection and control of this clone to prevent future spread outside the ICU.  相似文献   
3.
4.
IntroductionPeople with Down syndrome (DS) have high respiratory morbidity, evaluating their respiratory health with standardized, objective tests is desirable. Thus, the objective of this study was to evaluate the technical quality of Pulmonary Function Tests (PFTs) to determine which ones are most suitable for this population.MethodsParticipants included children, teenagers and adults with DS, 5 years of age or older (n = 302). The technical quality of the impulse oscillometry system (IOS), forced spirometry, lung-diffusing capacity for carbon monoxide (DLCO), and 6-min walk test (6MWT) were analyzed by age group. Capnography and pulse oximetry were included in the study. Technical quality was determined on the basis of current international PFTs standards.ResultsFifty-one percent of participants were males. A total of 184 participants (71%) who completed the IOS fulfilled the quality criteria, while 210 (70%) completed the 6MWT. Performance on forced spirometry and DLCO was poor. All pulse oximetries and 96% percent heart rates obtained had good quality, but exhaled carbon dioxide (PetCO2) and respiratory rate (RR) showed deficient repeatability.ConclusionsIOS appears to be the most reliable instrument for evaluating lung mechanics in individuals with DS.  相似文献   
5.
正The emerging role of gut microbiota as a key player in the development of neurodegenerative disorders:Mammals have evolved togetherwithcommensalmicrobiotatoestablishasymbioticrelationship in which they regulate reciprocally by synthesizing and responding to several common chemical substances. In this regard, gut microbiota  相似文献   
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7.
We report on 3 patients with pseudoathetosis, which are involuntary, slow, writhing movements due to loss of proprioception.  相似文献   
8.
Barium can induce spontaneous activity in cardiac non-pacemaker cells. The mechanism of barium induced diastolic depolarisation was studied in isolated ventricular myocytes, using a microelectrode technique. Barium (0.05-0.2 mmol.litre-1) decreased resting potential and caused the membrane potential at the end of the action potential to undershoot the diminished resting value temporarily, thereby inducing diastolic depolarisation. Resting membrane resistance was increased by Ba but at the end of phase 3 repolarisation the resistance temporarily decreased below its steady state diastolic value. In presence of Ba, hyperpolarisation abolished or reversed diastolic depolarisation. At the end of phase 3 repolarisation, membrane resistance was decreased, whether diastolic depolarisation was present, absent or reversed. A high [K]o (15.4 mmol.litre-1) decreased Ba effects on action potential, membrane resistance and diastolic depolarisation. Caesium decreased the Ba induced diastolic depolarisation and the associated increase in membrane resistance, but had little effect on spontaneous activity at depolarised levels. Barium induced an oscillatory potential, with increased membrane resistance. Noradrenaline plus low [Ba]o, and high [Ba]o alone (1-5 mmol.litre-1), can induce spontaneous activity. Thus, in myocardial cells barium induces diastolic depolarisation at polarised levels by a voltage and time dependent block of potassium conductance, which is modulated by action potential voltage changes. However, as [Ba]o is increased, spontaneous activity at a depolarised level may be related to the decay of potassium currents and to oscillatory potentials.  相似文献   
9.
BACKGROUND: The role of local excision for pT2 distal rectal cancer has been challenged because of the observation of high rates of lymph node metastases and local failure. However, neoadjuvant chemoradiation therapy (CRT) has led to increased local disease control and significant tumor downstaging, possibly decreasing rates of lymph node metastases. In this setting, a possible role for local excision of ypT2 has been suggested. METHODS: A total of 401 patients with distal rectal cancer underwent neoadjuvant CRT. Tumor response assessment was performed after at least 8 weeks from CRT completion. One hundred and twelve patients with complete clinical response were not immediately operated on and were excluded from the study, and 289 patients with incomplete clinical response were managed by radical surgery. Patients with final pathological stage ypT2 were analyzed to determine the risk of unfavorable pathological features that could represent unacceptable risk for local failure after local excision. RESULTS: Eighty-eight (30%) patients had ypT2 rectal cancer. Final ypT status was not associated with pretreatment radiological staging (p = 0.62). ypT status was significantly associated with the risk of lymph node metastases, risk of perineural and vascular invasion, and recurrence (p = 0.001). Lymph node metastases were present in 19% of patients with ypT2 rectal cancer. The risk of lymph node metastases in ypT2 was associated with the presence of perineural invasion (47% vs 4%; p = <0.001), vascular invasion (59% vs 6%; p < 0.001), and decreased mean interval CRT surgery (12 vs 18 weeks; p < 0.001), but not with mean tumor size (3.2 vs 3.1 cm; p = 0.8). Disease-free and overall survival rates were significantly better for patients with ypT2N0 (p = 0.02 and 0.006, respectively). Fifty-five (63%) patients with ypT2 had at least one unfavorable pathological feature for local excision (lymph node metastases, vascular or perineural invasion, mucinous type or tumor size >3 cm). CONCLUSION: Lymph node metastases were present in 19% of patients with ypT2 and were significantly associated with poor overall and disease-free survival rates. The risk of lymph node metastases could not be predicted by radiological staging or tumor size. Radical surgery should be considered the standard treatment option for ypT2 rectal cancer after CRT.  相似文献   
10.
股骨干骨折--扩髓和不扩髓髓内钉比较   总被引:4,自引:0,他引:4  
治疗股骨干骨折,采用不扩髓髓内钉比扩髓髓内钉手术时间明显缩短,而且失血也少。但是,扩髓钉的骨愈合更快,延迟愈合更少。两者都没有显著增加包括肺损害等其它并发症的风险。功能结果不能确定。  相似文献   
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