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排序方式: 共有659条查询结果,搜索用时 15 毫秒
21.
Lubaroff David M. Vaena Daniel Brown James A. Zehr Pamela Griffith Karen C. Brown Erica Eastman Julie Nepple Kenneth Kattula Ambika Williams Richard D. 《Immunologic research》2014,59(1-3):229-235
Immunologic Research - Preclinical studies demonstrated the ability of an adenovirus/PSA (Ad/PSA) vaccine to induce strong anti-PSA immune responses, and these responses were capable of destroying... 相似文献
22.
Martin Osranek Kaniz Fatema Fatema Qaddoura Ahmed Al-Saileek Marion E Barnes Kent R Bailey Bernard J Gersh Teresa S M Tsang Kenton J Zehr James B Seward 《Journal of the American College of Cardiology》2006,48(4):779-786
OBJECTIVES: This study sought to identify preoperative predictors of postoperative atrial fibrillation (POAF) among patients undergoing cardiac surgery. BACKGROUND: Postoperative atrial fibrillation is frequent after cardiac surgery and is associated with increased morbidity, mortality, prolonged hospital stay, and increased costs. Left atrial volume (LAV), a marker of chronically elevated left ventricular filling pressure, is a predictor of atrial fibrillation (AF) in the nonsurgical setting. METHODS: A total of 205 patients (mean age 62 +/- 16 years; 35% women) undergoing cardiac surgery were prospectively enrolled. Clinical risk factors were obtained by detailed medical record review and patient interview. Preoperative transthoracic echocardiograms were performed for assessment of LAV, left ventricular ejection fraction, and diastolic function. Follow-up was complete. Detection of POAF was based on documentation of AF episodes by continuous telemetry throughout hospitalization. RESULTS: Postoperative atrial fibrillation occurred in 84 patients (41.4%) at a median of 1.8 days after cardiac surgery. The LAV was significantly larger in patients in whom AF developed (49 +/- 14 ml/m2 vs. 39 +/- 16 ml/m2, p = 0.0001). Patients with LAV >32 ml/m2 had an almost five-fold increased risk of POAF, independently of age and clinical risk factors (adjusted hazard ratio 4.84, 95% confidence interval 1.93 to 12.17, p = 0.001). Age and LAV were the only independent predictors of POAF. The area under the receiver-operator characteristics curve to predict POAF was 0.729 for LAV and 0.768 for the combination of LAV and age (both p < 0.0001). CONCLUSIONS: The LAV is a strong and independent predictor of POAF. Risk stratification using LAV and age enables clinicians to identify high-risk patients before cardiac surgery. 相似文献
23.
24.
Ca2+ and phospholipid-dependent protein kinase (protein kinase C) activity is not necessarily required for secretion by human neutrophils 总被引:2,自引:0,他引:2
Ca2+-dependent and phospholipid-dependent protein kinase (PKC) is a receptor for and is activated by phorbol esters. This enzyme is reportedly involved in the mechanism of superoxide anion (O2-) production and the release of intracellular granule contents from human neutrophils. As previously reported by others, we found that greater than 75% of the total cellular PKC activity existed in a soluble form in untreated neutrophils and that this activity was enhanced in a dose- dependent manner by phorbol 12-myristate 13-acetate (PMA) and by phorbol 12,13-dibutyrate (PDBu). Furthermore, mezerein, an analogue of PMA that is thought to be a competitive inhibitor, did not activate PKC, and on the contrary, inhibited PMA-stimulated activity in a dose- dependent manner. Pretreatment of intact neutrophils with PMA or PDBu caused the "translocation" of PKC activity to the insoluble cell fraction; PKC translocation was not detected after mezerein stimulation at any of the tested concentrations. Neither did mezerein cause an increase in intracellular Ca2+, as monitored by Quin 2 fluorescence. Both phorbol esters and mezerein stimulated intact neutrophils to generate O2- and release lysosomal enzymes into the extracellular medium. Finally sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis demonstrated key differences in the patterns of endogenous phosphoproteins of neutrophils stimulated with phorbol as compared with mezerein. We therefore suggest that PKC activation may not be the only pathway required to elicit neutrophil responses. 相似文献
25.
KJ Kleizen A Hunck MH Wijnen JMTh Draaisma 《Acta paediatrica (Oslo, Norway : 1992)》2009,98(11):1822-1824
Aim: The classical combination of abdominal pain, vomiting, rectal blood loss and a palpable abdominal mass is only present in a minority of children with intussusception. Neurological signs and symptoms have been described, but are not a well understood phenomenon. We performed a retrospective study to ascertain the frequency and nature of these symptoms and to describe the characteristics of the patients presenting in this atypical way.
Methods: The records of 58 children presenting with intussusception from 2003 to 2008 were reviewed for abdominal and neurological signs and symptoms, duration of symptoms and effectiveness of treatment.
Results: In 10 out of 58 patients (17%), one or more neurological symptoms were recorded at presentation, with lethargy being the most frequent, followed by hypotonia and fluctuating consciousness. The patients with neurological abnormalities were significantly younger and presented with a shorter duration of symptoms. Therapy was more invasive, although not statistically significant, in this patient category.
Conclusion: Intussusception should be considered in the differential diagnosis in young children presenting with lethargy, hypotonia and/or sudden alterations of consciousness even in the absence of the classical symptoms of intussusception. 相似文献
Methods: The records of 58 children presenting with intussusception from 2003 to 2008 were reviewed for abdominal and neurological signs and symptoms, duration of symptoms and effectiveness of treatment.
Results: In 10 out of 58 patients (17%), one or more neurological symptoms were recorded at presentation, with lethargy being the most frequent, followed by hypotonia and fluctuating consciousness. The patients with neurological abnormalities were significantly younger and presented with a shorter duration of symptoms. Therapy was more invasive, although not statistically significant, in this patient category.
Conclusion: Intussusception should be considered in the differential diagnosis in young children presenting with lethargy, hypotonia and/or sudden alterations of consciousness even in the absence of the classical symptoms of intussusception. 相似文献
26.
Gestational PFOA exposure of mice is associated with altered mammary gland development in dams and female offspring. 总被引:1,自引:0,他引:1
Sally S White Antonia M Calafat Zsuzsanna Kuklenyik LaTonya Villanueva Robert D Zehr Laurence Helfant Mark J Strynar Andrew B Lindstrom Julie R Thibodeaux Carmen Wood Suzanne E Fenton 《Toxicological sciences》2007,96(1):133-144
Perfluorooctanoic acid (PFOA), with diverse and widespread commercial and industrial applications, has been detected in human and wildlife sera. Previous mouse studies linked prenatal PFOA exposure to decreased neonatal body weights (BWs) and survival in a dose-dependent manner. To determine whether effects were linked to gestational time of exposure or to subsequent lactational changes, timed-pregnant CD-1 mice were orally dosed with 5 mg PFOA/kg on gestation days (GD) 1-17, 8-17, 12-17, or vehicle on GD 1-17. PFOA exposure had no effect on maternal weight gain or number of live pups born. Mean pup BWs on postnatal day (PND) 1 in all PFOA-exposed groups were significantly reduced and decrements persisted until weaning. Mammary glands from lactating dams and female pups on PND 10 and 20 were scored based on differentiation or developmental stages. A significant reduction in mammary differentiation among dams exposed GD 1-17 or 8-17 was evident on PND 10. On PND 20, delays in normal epithelial involution and alterations in milk protein gene expression were observed. All exposed female pups displayed stunted mammary epithelial branching and growth at PND 10 and 20. While control litters at PND 10 and 20 had average scores of 3.1 and 3.3, respectively, all treated litters had scores of 1.7 or less, with no progression of duct epithelial growth evident over time. BW was an insignificant covariate for these effects. These findings suggest that in addition to gestational exposure, abnormal lactational development of dams may play a role in early growth retardation of developmentally exposed offspring. 相似文献
27.
Unilateral haemorrhagic parenchymal lesions in the preterm infant: shape, site and prognosis 总被引:2,自引:0,他引:2
KJ Rademaker F Groeneadaal GH Jansen P Eken LS De Vries 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(6):602-608
Rademaker KJ, Groenendaal F, Jansen GH, Eken P, de Vries LS. Unilateral haemorrhagic parenchymal lesions in the preterm infant: shape, site and prognosis. Acta Pædiatr 1994;83:602–8. Stockholm. ISSN 0803–5253 In a prospective cranial ultrasound study of 544 infants with a gestational age of 32 weeks or less, 20 (3.6%) infants were diagnosed as having a unilateral parenchymal lesion (PL). Based on the shape of the PL and the evolution on ultrasound, the infants were divided into three groups: group I consisted of 11 infants, in whom the PL was triangular/fan-shaped and separate from the ventricle. The PL evolved into small cystic lesions; group II comprised 3 infants who had a PL with a similar shape, but partially communicating with the ventricle; group III consisted of 6 infants who had a globular-shaped lesion in communication with the ventricle. In groups II and III, the PL evolved into one porcncephalic cyst. The PL was considered to be due to venous infarction in all cases with intraventricular haemorrhage preceding the PL in 7 cases. Sixteen infants survived. A postmortem was performed in 2 of the 4 infants who died, confirming the diagnosis of venous infarction. Neurologicdl sequelae were present in only 2 cases in the first group, while all 6 survivors of the other two groups developed mild to severe hemiplegia. Long-term follow-up was not always available and 4 of the 18 survivors were still less than 18 months when last seen. In 9 of the 11 infants in group I, the PL was localized in the frontoparietal region, while in 8 of the 9 infants in group II or III, the PL was beyond the trigone in the occipital region. The outcome of the unilateral PL is not always unfavourable. It was evident that not only the shape of the lesion and whether or not there was communication with the lateral ventricle, but also the site of the lesion (whether or not it extended into the occipital periventricular white matter) appeared to be important with regard to neurodevelopmental outcome. 相似文献
28.
Ultrasonic features of 21 surgically confirmed pyogenic liver abscesses in 18 patients were analyzed. Typical lesions were round or ovoid with a discrete, irregular, echo-poor margin. The number and intensity of internal echoes and sound transmission were variable. Such lesions can be aspirated percutaneously for definitive preoperative diagnosis. Pyogenic liver abscesses appear to have more ragged walls and are less frequently elliptical or multilocular than abscesses elsewhere in the abdomen. 相似文献
29.
Anatomy and pathology of the kidney by gray scale ultrasound 总被引:1,自引:0,他引:1