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161.
Phenotypic characteristics, antimicrobial susceptibility profile, and clinical-epidemiological features of 28 Nocardia strains isolated from 19 cases of bovine mastitis, eight cutaneous-subcutaneous lesions and one case of pneumonia in dogs were evaluated. Microbiological, biochemical, cytological and scanning electron microscopy methods were used in diagnosis. Nocardia asteroides type IV, Nocardia otitidiscaviarum,Nocardia nova (type III) and Nocardia farcinica (type V) were isolated from bovine milk, bronchial lavage and/or cutaneous-subcutaneous abscesses in dogs. Nocardial bovine mastitis was diagnosed predominantly in clinical cases, in dairy herds with poor environmental hygienic conditions between milking and inappropriate intramammary therapy. Canine nocardiosis was observed commonly in animals co-infected with distemper virus. Sulphamethoxazole-trimethoprim (92.8%), amikacin (92.8%) and ceftiofur (92.8%) were the most effective drugs in 28 isolates. Multiple drug resistance to three or more and five or more antimicrobials was observed in ten (35.7%) and three (10.7%) strains, respectively, predominantly with use of cloxaxillin, cefoperazone and ampicillin. The species (type) classification, clinical-epidemiological characteristics, diagnosis, multiple-drug resistance and public health considerations in Nocardia strains isolated from cattle and dogs in Brazil are discussed, with special reference to report of bovine mastitis by N. otitidiscaviarum by first time in Brazil and the similarity between Nocardia species isolated from human and animal origin.  相似文献   
162.
Adhesins (P-fimbriae, S-fimbriae, type 1 fimbriae and afimbrial adhesin), toxins (alpha-hemolysin and cytotoxic necrotizing factor type 1), iron acquisition systems (aerobactin) and host defense avoidance mechanisms (capsule or lipopolysaccharide) have been shown to be prevalent in Escherichia coli strains associated with urinary tract infections. In this work, 162 Uropathogenic Escherichia coli (UPEC) strains from patients with cystitis were genotypically characterized by polymerase chain reaction (PCR) assay. We developed three multiplex PCR assays for virulence-related genes papC, papE/F, papG alleles, fimH, sfa/foc, afaE, hly, cnf-1, usp, cdtB, iucD, and kpsMTII, all of them previously identified in UPEC strains. The PCR assay results identified 158 fimH (97.5%), 86 kpsMTII (53.1%), 53 papC/papEF/papG (32.7%), 45 sfa (27.8%), 42 iucD (25.9%), 41 hly (25.3%), 36 usp (22.2%), 30 cnf-1(18.5%) and 10 afa (6.2%) strains. No strain was positive for cdtB. In this work, we also demonstrated that adhesins may be multiple within a single strain and that several virulence genes can occur combined in association.  相似文献   
163.
The usual surgical treatment of tricuspid endocarditis is valve replacement or valve excision alone without valve replacement. 'Vegetectomy', i.e. local excision of the vegetation and leaflet repair, has been previously described and can be applied to cases with well-circumscribed vegetations and little or no valve damage. A case of tricuspid valve endocarditis successfully managed by surgical excision of the vegetation is reported.  相似文献   
164.
This study was designed to describe the epidemiology and risk factors for nosocomial infection (NI) in a Brazilian neonatal intensive care unit (NICU). This study was a retrospective cohort from January to December, 2003. All neonates admitted to the NICU. Infection surveillance was conducted according to the NNIS, CDC. Chi-square test and logistic regression model were performed for statistical analyses. The study was conducted at a public, tertiary referral NICU of a teaching hospital in the Northeast of Brazil. A total of 948 medical records were reviewed. Overall NI incidence rate was 34%. The main neonatal NI was bloodstream infection (68.1%), with clinical sepsis accounting for 47.2%, and pneumonia was the second most common NI (8.6%). Multivariate analysis identified seven independent risk factors for NIs: birth weight, exposure to parenteral nutrition, percutaneous catheter, central venous catheter or mechanical ventilation, abruptio placentae and mother's sexually transmitted disease (STD). Neonates from mothers with STD or abruptio placentae, those weighing less than 1,500 g at birth or those who used invasive devices were at increased risk for acquiring NI.  相似文献   
165.
OBJECTIVES: To evaluate the performance of laboratory diagnosis of tuberculosis, clinical samples underwent culture, species identification and drug susceptibility testing (DST). METHODS: A total of 554 samples from 269 patients were tested for smear microscopy using Kinyoun stain. Culture was performed in Ogawa-Kudoh medium and species identification was performed using the IS6110 amplified region. DST for rifampicin, isoniazid (INH) and streptomycin were carried out using the Resazurin assay. RESULTS: Cultures augmented the number of cases diagnosed by 22.1%, IS6110 amplification identified all Mycobacterium tuberculosis strains thus isolated and DST detected three strains resistant to INH and one multidrug-resistant strain. CONCLUSION: Simultaneous use of different techniques enhanced culture yield, species identification and detection of drug resistance even in a laboratory with limited facilities.  相似文献   
166.
Gastric stump mucosa: is there a risk for carcinoma?   总被引:4,自引:0,他引:4  
BACKGROUND: Patients who underwent partial gastric resections are at an increased risk for the development of cancer in the gastric remnant. AIM: To assess the long-term patients who underwent surgical treatment for peptic ulcer disease through endoscopic and pathologic evaluation of the gastric stump mucosal alterations. PATIENTS AND METHODS: Between 1987 and 1990, 154 patients (mean = 20.4 years after gastrectomy) were evaluated by upper digestive endoscopy with multiple biopsies and pathological examination. RESULTS: Endoscopic alterations were present in 111 patients (72.1%). The commonest pathologic alterations were foveolar hyperplasia, intestinal metaplasia and cystic dilation. Severe dysplasia was noted in two (1.25%) and carcinoma in 13 (8.4%) of the cases. In four patients (3.8%) the endoscopic findings did not show any evidence of tumors, however they were detected due to multiple biopsies and histologic studies. CONCLUSIONS: Surveillance of these patients with endoscopy and multiple biopsies may provide the means to diagnose tumors at an early stage, but the cost benefit ratio of surveillance requires further study.  相似文献   
167.
During June 1997-June 1999 rotavirus infection was screened in infants aged up to 2 years and hospitalised with acute diarrhoea in S?o Luís, Northeastern Brazil. Altogether, 128 stool samples were collected from diarrhoeic patients and additional 122 faecal specimens from age and temporal matched inpatients without diarrhoea were obtained; rotavirus positivity rates for these groups were 32.0% (41/128) and 9.8% (12/122), respectively (p < 0.001). Both electropherotyping and serotyping could be performed in 42 (79.2%) of the 53 rotavirus-positive stool samples. Long and short electropherotypes were detected at similar rates--38.1% and 40.5% of specimens, respectively. Overall, a G serotype could be assigned for 35 (83.3%) of specimens, the majority of them (66.7%) bearing G1-serotype specificity. Taking both electropherotypes and serotypes together, G1 rotavirus strains displaying long and short RNA patterns accounted for 30.9% and 19.0% of tested specimens, respectively; all G2 strains had short electropherotype. Rotavirus gastroenteritis was detected year-round and, in 1998, the incidence rates tended to be higher during the second semester than in the first semester: 45.2% and 26.1% (p = 0.13), respectively. Rotavirus infections peaked at the second semester of life with frequencies of 30.1% and 13.5% for diarrhoeic children and controls, respectively. While the six rotavirus strains bearing G2-type specificity were circulating throughout the whole study period, G1 serotypes (n = 27) emerged as from June 1998 onwards, 20 (74.1%) of which clustering in 1998. These data underscore the importance of rotaviruses in the aetiology of severe infantile gastroenteritis in Northeastern Brazil and sustain the concept that a future vaccine should confer protection against more than one serotype.  相似文献   
168.
169.
St Jude Total Therapy Study XIIIB for childhood acute lymphoblastic leukemia (ALL) incorporated more stringent risk classification, early intensification of intrathecal chemotherapy, reinduction treatment, and the addition of dexamethasone to postremission therapy to increase the proportion of event-free survivors without jeopardizing their quality of life. Cranial irradiation was reserved for the 12% of patients who had T-cell ALL and a presenting leukocyte count of 100 x 10(9)/L or more, or CNS-3 (5 or more leukocytes/microL with identifiable blast cells in an atraumatic sample or the presence of cranial nerve palsy) status. Among the 247 consecutive patients enrolled in the study, 117 were classified as having lower-risk leukemia and received mainly antimetabolite-based continuation therapy; the 130 cases with higher-risk leukemia received more intensive continuation chemotherapy with multiple drug pairs administered in weekly rotation. The 5-year event-free survival estimate was 80.8% +/- 2.6% (SE); the 8-year rate was 78.6% +/- 5.8%. The 5-year cumulative risk of an isolated central nervous system (CNS) relapse was 1.7% +/- 0.8%, and that of isolated plus combined CNS relapse was 3.0% +/- 1.1%. The 5-year cumulative risks of etoposide-related myeloid malignancies were 1.8% +/- 1.3% in the lower-risk patients who received a cumulative dose of 1.2 g/m(2) and 5.0% +/- 2.0% in the higher-risk patients who received a cumulative dose of up to 14.4 g/m(2) (P = .18). Independent adverse prognostic features included the presence of MLL-AF4 or BCR-ABL fusion gene and minimal residual leukemia of 0.01% or more at the end of the 6-week remission induction phase. Our results suggest the efficacy of early intensification of intrathecal chemotherapy and provide the basis for studies omitting cranial irradiation altogether.  相似文献   
170.
The medical records of 412 residents of three southeastern Massachusetts nursing homes were reviewed to examine the frequency and medical management of urinary incontinence and the indications for chronic urinary catheterization. The mean age of the patients was 84.1 years. In this study 9.7% of the patients were managed with a urinary catheter, while an indication for catheterization was recorded in the medical records of only 27.5% of these patients. Half of the noncatheterized nursing home patients were transiently or permanently incontinent of urine, but were not catheterized. Incontinent patients without catheters were more likely to require assistance in toileting (75.5 v 26.1%) or to have bacteriuria (60.1 v 26.1%) than continent patients. Despite the frequency of urinary incontinence, this problem was included in the medical problem list of less than 5% of the incontinent nursing home patients. The authors conclude that urinary incontinence is a frequent medical problem in the nursing home population, but it is rarely recorded and evaluated as a medical problem. Furthermore, indications for urinary catheterization frequently are also not recorded. An explanation for this practice was not determined, but possibilities include a lack of physician knowledge of the evaluation and management of incontinence and a nonaggressive approach to such patients, given their other medical problems.  相似文献   
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