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991.
992.
We report the isolation of Leishmania infantum zymodeme MON-98 in Portugal, its first known occurrence outside the focus of El Agamy, Egypt. One dog found to be infected with Acanthocheilonema dracunculoides during a survey of canine filariosis in the Alto Douro region, north-east Portugal, was also discovered to have Leishmania in bone marrow. The isolated strain was identified by isoenzyme analysis. A search for other possible cases of L. infantum MON-98 infection in dogs, vectors and particularly humans is necessary to establish the real epidemiological importance of this zymodeme in the endemic region of Alto Douro.  相似文献   
993.
In 12 mechanically-ventilated, anesthetized, paralyzed patients undergoing cardiac surgery for either coronary bypass (six subjects) or to correct valvular disfunctions, volume, airflow, tracheal, esophageal, and transpulmonary pressures were measured. Respiratory system elastance and resistance were partitioned into lung and chest wall components. Resistances were further split into homogeneous and uneven elements. Measurements were performed prior to thoracotomy and just after rib cage closure. Before surgery, valvular patients had significantly higher elastances and uneven resistances of the respiratory system and lung than those with ischemic heart disease. Postoperatively, the patients presented with an increase in respiratory system and lung elastances, a decrease in pulmonary resistance, and a rise in chest wall resistance. Surgically induced mechanical changes were similar in ischemic and valvular patients.  相似文献   
994.
A few authors have reported, especially as intraoperative complications, gastrointestinal hemorrhage related to liver transplantation. The aim of this study was to show two cases of gastrointestinal hemorrhage, which occurred during surgery. The first patient was male, 46 years old, with viral hepatic cirrhosis. He had previously presented two episodes of digestive bleeding. Upper digestive endoscopy showed esophageal gastric varices. During the hepatectomy there was bleeding inside the nasogastric tube associated with severe hemodynamics instability without other sources of bleeding. Intraoperative endoscopy evidenced bleeding gastric varices. Gastrectomy was carried out and the varices were tied. The piggyback technique was used in the liver transplantation. The surgery was concluded without problems and in the following four and a half years his condition has evolved well. In the second case, the patient was aged 17, female, with autoimmune hepatic cirrhosis. She had previously presented one episode of digestive bleeding. Intraoperative endoscopy showed median esophageal varices. During the anesthetic induction she presented an episode of hematemesis. A Sengstaken-Blakemore balloon was introduced. The transplant was performed without further problems. Her case has been followed for 14 months in the outpatients' clinic with a good postoperative course. To sum up, gastrointestinal hemorrhage can be due to portal hypertension during the liver transplantation and must be treated quickly. In these cases the surgery must be ongoing.  相似文献   
995.
Schistosomiasis continues to be a significant public health problem in tropical countries such as Brazil. Even though drug treatment in endemic areas has been shown to be efficient for controlling morbidity, it does not reduce prevalence due to constant reinfections. Therefore, a long-term disease control strategy is needed combining mass chemotherapy with a protective vaccine. Although the field of vaccine development has experienced more failures than successes, encouraging results have been obtained in recent years using defined recombinant derived Schistosoma mansoni antigens. This article primarily reviews the progress in the development of a vaccine against S. mansoni in Brazil. We discuss here different forms of vaccine tested in Brazil in pre-clinical trials and immunologic studies performed with patients in endemic areas of schistosomiasis. Lastly, we reviewed the S. mansoni genomic projects developed in the country and the recent advances in the identification of new molecules with potential as vaccine targets.  相似文献   
996.
Background:The incidence of restenosis of the coronary artery after a bare-metal stent implant has been lower than in simple balloon angioplasty; however, it still shows relatively high rates.Objective:The aim of this study was to find new risk indicators for in-stent restenosis using carotid ultrasonography, that, in addition to the already existing indicators, would help in decision-making for stent selection.Methods:We carried out a cross-sectional prospective study including 121 consecutive patients with chronic coronary artery disease who had undergone percutaneous coronary intervention with repeat angiography in the previous 12 months. After all cases of in-stent restenosis were identified, patients underwent carotid ultrasonography to evaluate carotid intima-media thickness and atherosclerosis plaques. The data were analyzed by Cox multiple regression. The significance level was set a p<0.05.Results:Median age of patients was 60 years (1st quartile = 55, 3rd quartile = 68), and 64.5% of patients were male. Coronary angiography showed that 57 patients (47.1%) presented in-stent restenosis. Fifty-five patients (45.5%) had echolucent atherosclerotic plaques in carotid arteries and 54.5% had echogenic plaques or no plaques. Of patients with who had echolucent plaques, 90.9% presented coronary in-stent restenosis. Of those who had echogenic plaques or no plaques, 10.6% presented in-stent restenosis. The presence of echolucent plaques in carotid arteries increased the risk of coronary in-stent restenosis by 8.21 times (RR=8.21; 95%CI: 3.58-18.82; p<0.001).Conclusions:The presence of echolucent atherosclerotic plaques in carotid artery constitutes a risk predictor of coronary instent restenosis and should be considered in the selection of the type of stent to be used in coronary angioplasty.  相似文献   
997.
We have previously shown that early human CD34high hematopoietic progenitors are maintained quiescent in part through autocrine transforming growth factor-beta 1 (TGF-beta 1). We also demonstrated that, in the presence of interleukin-3, interleukin-6, granulocyte colony-stimulating factor, and erythropoietin, TGF-beta 1 antisense oligonucleotides or anti-TGF-beta serum have an additive effect with KIT ligand (Steel factor [SF]), which suggests that they control different pathways of regulation in these conditions. This finding also suggests that autocrine TGF-beta 1 might suppress c-kit expression in primitive human hematopoietic progenitors. We have now distinguished two subpopulations of CD34high cells. One subpopulation expresses a c- kit mRNA that can be downmodulated by exogenous TGF-beta 1 within 6 hours. Another subpopulation of early CD34high cells expresses a low or undetectable level of c-kit mRNA, but its expression can be upmodulated within 6 hours by anti-TGF-beta. These effects disappear 48 hours after induction and cannot be maintained longer than 72 hours, even if TGF- beta 1 or anti-TGF-beta serum are added every day. Similar kinetics, although delayed, are observed with KIT protein expression. On the contrary, no specific effect of TGF-beta 1 was observed on c-fms, GAPDH, and transferrin receptor gene expression in these early progenitors. These results clarify the complex interaction between TGF- beta 1 and SF in normal early hematopoietic progenitors. SF does not switch off the TGF-beta 1 inhibitory pathway. Autocrine TGF-beta 1 appears to maintain these cells in a quiescent state, suppressing cell division by downmodulating the receptor of SF, a key cytokine costimulator of early progenitors.  相似文献   
998.
BACKGROUND: Restenosis, or òAchilles heeló of balloon angioplasty, remains in a range near 30% and cannot be predicted with certainty. To find adequate methods for its foresight is a challenge. OBJECTIVES: To determine risk factors and an angiographic score to predict the appearance of restenosis after one-site percutaneous transluminal coronary angioplasty (PTCA). METHODS: We restudied prospectively 315 (239 men, 76 women, age range from 29 to 78, 53.6 +/- 9.5 years) of 360 patients who underwent PTCA to a native coronary artery. The study didn?t include patients with left main disease, total occlusion, side-branch involvement, ostial stenosis, acute phase of myocardial infarction or those who repeat PTCA. Two-hundred twenty-eight patients underwent PTCA of the left anterior descending artery, 56 of the right coronary artery and 31 of the left circumflex artery. RESULTS: Restenosis, defined as a luminal renarrowing > 50% at follow-up, was present in 82 (26%) patients between 1 and 8 months after the procedure. Univariate and multivariate analysis revealed four vascular factors related to restenosis (p < 0.05): a) lesion length and; b) irregularity of the lesion borders before PTCA; c) perivascular and/or endovascular haziness and; d) intensity of residual stenosis after PTCA. To construct the score, a zero was given to a lesion length < 8 mm; to smooth lesion borders; to residual stenosis up to 20%; and to absence of haziness after PTCA. A one was given to a lesion length between 8 and 10 mm; and to a lesion with irregular borders. A two was given to a lesion length > 10 mm. A three was given to a residual stenosis > 20%; and to the presence of haziness after PTCA. The sum of all terms was considered the final score. So, it could oscillate from 0 to 9. Calculated score from 0 to > 5 showed respective restenosis rates of (%): 5.2; 15.1; 24.0; 39.4; 44.8; 60.8; and 84.2. The calculated correlation coefficient (0.98) among the scored values and the correspondent restenosis rates was highly significant (p < 0.001). CONCLUSIONS: It is concluded that restenosis is primarily a multifactorial problem based on vascular factors and may be predicted with a high degree of probability by the proposed score.  相似文献   
999.
1000.
BACKGROUND/AIMS: Gene therapy is a promising approach for treatment of hepatocellular carcinoma (HCC). However, transduction of non-tumoral hepatocytes may lead to severe hepatitis when using suicide gene therapy approaches. The aim of our study was to evaluate the gene transfer efficiency into HCC cells and normal hepatocytes using human immunodeficiency virus (HIV)-derived lentiviral vectors in vitro and in vivo. METHODS: Lentiviral vectors encoding for the LacZ gene or the fusion gene HSV-Tk/GFP were tested in vitro in human HCC cells and human hepatocytes in primary culture and in vivo in a chemically induced rat model of HCC. RESULTS: We show that HIV-1-derived lentiviral vectors are efficient in transducing HCC cells in vitro and in vivo. No significant transduction of non-tumorous hepatocytes was observed in vivo whatever the route of administration used. Measurement of tumor growth following direct intratumoral injection of a lentiviral vector containing the HSV-Tk gene and GCV treatment showed a strong antitumoral efficacy in the absence of normal liver toxicity. CONCLUSIONS: These observations suggest that lentiviral vectors allow an antitumoral effect with low liver toxicity when using suicide gene therapy approach and could be efficient tools for HCC gene therapy.  相似文献   
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