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排序方式: 共有826条查询结果,搜索用时 31 毫秒
1.
Selwyn Arlington Headley Nayara Emily Viana Mariana de Mello Zanim Michelazzo Ana Aparecida Correa Xavier Cícero Júlio Silva Costa Felipe Hideki Ogo de Pinho Marcelo Diniz dos Santos 《Transboundary and Emerging Diseases》2020,67(Z2):49-59
Neorickettsia helminthoeca (NH), the agent of salmon poisoning disease or canine neorickettiosis (CN), is a bacterial endosymbiont of the nematode Nanophyetus salmincola, and infections are spreading among specific fish‐eating mammalians. This article describes the pathologic and immunohistochemical findings associated with spontaneous NH‐induced infections in dogs from Southern Brazil. The principal pathologic findings were hypertrophy of Peyer patches and lymphadenopathy with lymphocytic proliferation, chronic interstitial pneumonia, and chronic enteritis associated with positive intralesional immunoreactivity to antigens of NH within macrophages and histiocytes. Positive immunoreactivity against canine parvovirus‐2 (CPV‐2) or/and canine distemper virus was not detected in the evaluated intestinal segments or in the samples from the cerebellum and lungs, respectively, from the dogs evaluated. These findings demonstrated that NH was involved in the enteric, pulmonary, and lymphoid lesions herein described, and provide additional information to confirm the occurrence of this bacterial endosymbiont within this geographical location. It is proposed that chronic pneumonia should be considered as a pathologic manifestation of NH‐induced infections. Additionally, our results show that the occurrences of CN seem to be underdiagnosed in Southern Brazil due to the confusion with the incidence of CPV‐2. 相似文献
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AIDS: what is now known. I. History and immunovirology 总被引:1,自引:0,他引:1
P A Selwyn 《Hospital practice (Office ed.)》1986,21(5):67-76, 81-2
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The antibacterial activity of cefpirome (HR810), a new cephalosporin, was compared with that of other "third-generation" cephalosporins, as well as cefuroxime, piperacillin and gentamicin. Cefpirome was the most active beta-lactam antibiotic against Gram-negative bacteria. The MIC90 for Enterobacteriaceae was always less than 0.5 ml/l except for Enterobacter species. The MIC90 against Pseudomonas species was 2 mg/l, which was equal to that of ceftazidime and gentamicin. Cefpirome was also more active than the other beta-lactam antibiotics against Staphylococcus aureus. A relatively high frequency of synergy was observed when cefpirome was combined with aminoglycosides against both Gram-positive and Gram-negative bacteria. No antagonism was detected. This antibiotic was very stable to both plasmid- and chromosomally-mediated beta-lactamases. It was more resistant to Enterobacter cloacae P99 enzyme than ceftazidime, cefotaxime and cefotetan. Its stability to the Klebsiella K1 beta-lactamase was more than that of cefotaxime and ceftriaxone but slightly less than that of ceftazidime and latamoxef. MBC90 values for cefpirome were generally less than twice the corresponding MIC values. 相似文献
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Eltoum IA Eloubeidi MA Chhieng DC Tamhane A Crowe R Jhala D St John KD Wilcox CM Siegal GP Vickers S Jhala NC 《American journal of clinical pathology》2005,124(5):697-707
Our objectives were to devise a cytologic grading system and determine whether it would predict survival of patients with solid-type pancreatic adenocarcinoma. We evaluated 116 consecutive patients from July 2000 to November 2002; they were followed up until September 2003. We scored the following features on rapid Romanowsky-stained endoscopic ultrasound-guided fine-needle aspiration smears: cell group architecture, single cells, nuclear grade, mucus, bizarre cells, and necrosis. A cytologic grade (low vs high) was assigned. The Kaplan-Meier estimate of 6-month survival was 76% (SE, 7%) for patients with low-grade tumors vs 50% (SE, 6%) for patients with high-grade carcinoma. The median survival for patients with low-grade vs high-grade tumors was 1 year vs 6 months, respectively (chi2 = 4.45; P = .035). Cox proportional hazards regression showed tumor stage, cancer-specific treatment, and cytologic grade to be independent predictors of survival (P = .001). No other factors (age, mass location, placement of stent, presence of concomitant chronic pancreatitis, race, sex) predicted survival. We devised a grading system that independently predicted survival in patients with pancreatic adenocarcinoma. 相似文献
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New and sensitive standard cell culture technique for the detection of cytomegalovirus in clinical specimens 总被引:1,自引:0,他引:1
S A Agha J C Coleman L A Mahmoud A M Abd-Elaal S Selwyn 《Journal of medical virology》1988,26(1):85-92
Conventional tube cell culture has been recognised as the most sensitive technique available for human cytomegalovirus (HCMV) detection. Low-speed centrifugation of specimen inocula onto cell culture monolayers has been shown to increase the efficiency of infection with the AD 169 strain of HCMV. Therefore a centrifugal force of 900g for 1 hour at 37 degrees C was used to enhance the detection of HCMV cytopathic effect (CPE) in shell vials that contained circular coverslips with a monolayer of human embryonic lung (HEL) fibroblasts. Of 195 specimens, HCMV CPE was detected in 18 specimens (9.02%) on shell vial culture assay, whereas conventional tube cell culture was positive in only 13 specimens (6.6%). The shell vial culture assay was significantly more sensitive (P less than 0.05). Furthermore the development of the cytopathic effect on shell vial culture assay was significantly earlier (P less than 0.01) and more extensive. Urine samples were sonicated and the results obtained with immunofluorescence using human immune serum demonstrated that sonication increased both the intensity of fluorescence and number of fluorescent foci of HCMV-infected cells and also decreased the non-specific fluorescence of the background. 相似文献
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Four coded, but otherwise unidentified, premedicants were prescribed in randomised order for 219 patients who were to undergo elective Caesarean section. Seventy-six (35%) of these patients affirmed at the pre-operative visit that they were not anxious. Diazepam 5 mg and lorazepam 1 mg appeared to be superior to the placebo and to 10-6 ml of 90% alcohol in inducing calmness and/or drowsiness, although the differences were not statistically significant. The incidence of awareness or unpleasant dreams was considerably higher in the placebo and alcohol series (6.2% and 7.5%) than in the diazepam and lorazepam series (nil and 2.1%). There was no remarkable difference in the condition of the immediate newly-born related to the premedicant received by the mother, any small differences being much less impressive than that related to the duration of the U-D interval. No notable differences were observed in the long term conditions between the infants in the placebo, alcohol and diazepam series but the incidence of "reluctance to feed". If relief from preoperative anxiety-and possibly a reduction in the likelihood of awareness-without undue effect upon the infant is considered desirable, diazepam 5 mg is the preferred choice from the four drugs investigated. 相似文献