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991.
Further evidence is presented incriminating the sandfly Lutzomyia longipalpis as the vector of Leishmania chagasi, the causative agent of American visceral leishmaniasis, in the Amazon Region of Brazil. During an outbreak of the disease in Santarém, Pará State, this insect was shown to be the only species of sandfly consistently present in and around the patient's homes, where it often occurred in very large numbers. Of 491 specimens dissected, 35 (7.14%) proved to be infected, and isolates of L. chagasi were made from 16 of 27 of these sandflies following the inoculation of the promastigotes into hamsters. Finally, the parasite was transmitted to four other hamsters which had been subjected to the bites of large numbers of wild-caught Lu. longipalpis. Isolates of Leishmania from Lu. longipalpis captures in Santarém, and in another focus of visceral leishmaniasis on the Island of Marajó, Pará, have been shown to be biologically and biochemically indistinguishable from the parasite infecting man, dogs and foxes in Pará, and from stocks obtained from man elsewhere in Brazil (Bahia and Ceará States).  相似文献   
992.
Rebreathing of expired air may be a lethal hazard for prone sleeping infants. This paper describes a mechanical model to simulate infant breathing, and examines the effects of bedding on exhaled air retention. Under simulated rebreathing conditions, the model allows the monitoring of raised carbon dioxide (CO2) inside an artificial lung-trachea system. Resulting levels of CO2 (although probably exaggerated in the mechanical model compared with an infant, due to the model's fixed breathing rate and volume) suggest that common bedding materials vary widely in inherent rebreathing potential. In face down tests, maximum airway CO2 ranged from less than 5% on sheets and waterproof mattresses to over 25% on sheepskins, bean bag cushions, and some pillows and comforters. Concentrations of CO2 decreased with increasing head angle of the doll, away from the face down position. Recreations of 29 infant death scenes also showed large CO2 increases on some bedding materials, suggesting these infants could have died while rebreathing.  相似文献   
993.
994.
We used the polymerase chain reaction to amplify DNA fragments specific to Toxoplasma gondii. The sensitivity of the technique allowed for the detection of as few as ten cultured T. gondii tachyzoites. We applied the same amplification technique to deparaffinized ocular sections from two cases of ocular toxoplasmosis. Although toxoplasmic cysts could only be seen in one eye by optical microscopy, polymerase chain reaction allowed the identification of the parasite in both cases. Our study indicates the feasibility of a sensitive DNA-based assay to complement pathologic studies of an ocular parasitic disease.  相似文献   
995.
Summary The eosinophilia-myalgia syndrome associated with L-tryptophan-containing products is highlighted by eosinophilia, incapacitating myalgias, and diverse multisystemic manifestations. In addition to involvement of the skin, skeletal muscle, and peripheral nerves, visceral damage has been quite prominent, particularly affecting the lungs, the heart, and the liver. Hepatic involvement has been manifested by altered liver tests but is clinically silent. We report the unique case of a woman with this syndrome who developed abdominal pain, a clinical picture of hepatitis and chronically abnormal liver tests. Histologic examination of the liver disclosed eosinophilic hepatitis with piecemeal necrosis. The occurrence of clinically overt hepatic involvement has not been reported previously. Potential mechanisms of liver damage in eosinophilia-myalgia syndromes are discussed.  相似文献   
996.
Breast disease: dynamic spiral MR imaging   总被引:19,自引:0,他引:19  
  相似文献   
997.
The isolation of Leishmania (V.) lainsoni is recorded for the first time from a wild animal, the rodent Agouti paca (Rodentia: Dasyproctidae), from Pará State, north Brazil. Isolates of the parasite were made from apparently normal skin of 3 specimens of this rodent captured on the Island of Tocantins, in the municipality of Tucuruí, an area subsequently flooded in the formation of the lake associated with the Tucuruí hydroelectric dam. No isolations were made from the viscera. Identification of the parasite was in each case based on morphology of the amastigotes and promastigotes, behavior of the organism in hamsters, isoenzymes profiles and the use of monoclonal antibodies. The inapparent nature of the infection leads us to suggest that the "paca", Agouti paca, represents a primitive host of L. (V.) lainsoni in the Amazon Region.  相似文献   
998.
International Urology and Nephrology - Whey protein has antioxidant properties through its amino acid cysteine, which enhances the biosynthesis of glutathione, the most abundant antioxidant...  相似文献   
999.
1000.
The objective was to evaluate the efficacy of multi‐layered silicone foam (intervention) compared with transparent polyurethane film (control) in preventing heel pressure injuries caused by surgical positioning of individuals undergoing elective surgery. It was designed an intra‐patient, open, parallel, randomised controlled trial was conducted in a university hospital in southern Brazil, from March 2019 to February 2020, with patients undergoing elective surgeries of cardiac and gastrointestinal specialties. The patients who met the selection criteria constituted, simultaneously, a single group receiving the intervention and active control, through paired analysis of the cutaneous sites (right heel and left heel). The outcome was the occurrence of PI, within the follow‐up period was 72 hours. Brazilian Registry of Clinical Trials: RBR‐5GKNG5. There was analysis of 135 patients/270 heels, with an overall incidence of 36.7%. The pressure injury incidence was significantly lower in the intervention group (26.7%), compared with the control group (P = .001); relative risk of 0.57. In the intervention group, the estimated pressure injury‐free time (survival) was 57.5 hours and in the control group, 43.9 hours. It was concluded that Multi‐layered silicone foam (intervention) is more efficacious than transparent polyurethane film (control) in the prevention of pressure injuries caused by surgical positioning of individuals undergoing elective surgery.  相似文献   
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