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排序方式: 共有1136条查询结果,搜索用时 15 毫秒
1.
Maria C. Chammas Andre C. Oliveira Mario J. D´Ávilla Pedro H. Moraes Marcelo Straus Takahashi 《Ultrasound in medicine & biology》2019,45(1):50-55
We prospectively evaluated the effectiveness of contrast-enhanced ultrasonography (CEUS) for differentiation of benign versus malignant portal vein thrombosis (PVT). We studied a total of 43 patients with chronic liver disease, hepatocellular carcinoma-suggestive nodules and confirmed PVT, in whom the nature of the PVT was confirmed by follow-up imaging (US, computed tomography and/or magnetic resonance imaging) performed up to 6 mo after CEUS. PVT was assessed by US, Doppler US and CEUS with respect to vessel wall disruption and/or invasion, color Doppler vascularization, pulsed Doppler vascularization pattern and CEUS enhancement and vascularization pattern, and thrombi were classified as benign or malignant based on these findings. Follow-up studies revealed malignant PVT in 22 of the 43 patients (51%) and benign PVT in 21 patients (49%). CEUS findings were consistent with follow-up studies in 41 of the 43 patients (95%), with κ?=?0.903 (p < 0.0001), sensitivity?=?91% and specificity?=?100%, indicating that CEUS can be confidently used to differentiate benign from malignant portal vein thrombosis in the setting of chronic liver disease. 相似文献
2.
Noninvasive Intracranial Cerebral Flow Velocity Evaluation in the Emergency Department by Emergency Physicians 总被引:2,自引:0,他引:2
Michael Shafé MD Michael Blaivas MD RDMS Edmond Hooker MD Leigh Straus BS 《Academic emergency medicine》2004,11(7):774-777
Transcranial Doppler (TCD) is an accepted modality for the evaluation of cerebral blood flow velocities. OBJECTIVES: The purpose of this study was to test the feasibility of bedside TCD measurement in the emergency department (ED) with critically ill, intubated patients. METHODS: A prospective convenience sample of patients presenting to a university hospital over a two-month period underwent TCD evaluation of the middle cerebral artery. Intubated patients with head trauma and any patient requiring tracheal intubation were eligible. A 2-MHz Doppler probe was positioned over the temporal bone to acquire blood flow velocities. An emergency medicine resident and research assistant obtained measurements. Continuous TCD tracings were recorded on a video cassette recorder tape for quality assurance review and data collection. Vital signs and therapeutic interventions were also recorded. Flow velocities were measured in cm/s; the peak Resistance Index (RI) was calculated for each patient. RESULTS: A total of 30 patients were enrolled in the study. Adequate tracings were obtained in 25 patients (83%) without a disruption of resuscitation. Tracings could not be obtained in five patients; they were listed as TCD failures. However, in two of these patients, adequate flow velocity tracings were obtained after resuscitation. Four patients were evaluated during tracheal intubation. One patient was monitored successfully during cardiopulmonary resuscitation. The median time required for data acquisition was 1.9 minutes. The mean highest RI for those who expired was 0.84. For those who survived, the mean highest RI was 0.52. The difference of 0.32 was statistically significant (p = 0.04). CONCLUSIONS: Noninvasive blood flow velocity monitoring of the middle cerebral artery using TCD is feasible in the ED when performed at the bedside on intubated patients with traumatic brain injury and others during tracheal intubation and resuscitation. 相似文献
3.
Patterns of gene expression and sites of latency in human nerve ganglia are different for varicella-zoster and herpes simplex viruses. 总被引:28,自引:2,他引:26
4.
Frank Baker Ph.D. David Jodrey Ph.D. James Intagliata Ph.D. Harry Straus Ph.D. 《Community mental health journal》1993,29(4):321-331
A cohort of 729 chronically mentally ill patients receiving community support services (CSS) were followed over a nine-month period. Receiving needed community support services was shown to predict change in client functioning as measured by the Global Assessment Scale (GAS) even after the initial values on the GAS, as well as demographic, psychiatric, residential and medication maintenance variables were considered. Adequacy of social support from family, friends and others also contributed to predicting change in global functioning of the CSS patients.Johns Hopkins UniversityPresented at the American Psychological Association Annual Meeting, Washington, D.C., August 16, 1992. 相似文献
5.
Acyclovir suppression of frequently recurring genital herpes. Efficacy and diminishing need during successive years of treatment 总被引:3,自引:0,他引:3
S E Straus K D Croen M H Sawyer A G Freifeld J M Felser J K Dale H A Smith C Hallahan S N Lehrman 《JAMA》1988,260(15):2227-2230
Forty-seven patients with frequently recurring genital herpes participated in one or more of five sequential trials of oral suppressive therapy with 200 mg of acyclovir three times daily from four to 12 months' duration. The prolonged use of acyclovir was extremely well tolerated, and treatment efficacy was sustained through successive studies. Recurrences in eight patients with repeated treatment "failures" were more effectively suppressed with higher doses of acyclovir. All patients experienced recurrent infections after the treatments were completed; however, the mean time to recurrence following each treatment period became progressively longer, and resumption of suppressive therapy was no longer warranted for ten patients. These data indicate the efficacy and safety of chronic suppressive therapy with acyclovir and the value of interrupting prolonged treatment to assess its further need. 相似文献
6.
Somatic cell hybrids formed by crossing PG19 mouse melanoma cells with mouse embryo fibroblasts have a reduced ability to proliferate in growth factor-unsupplemented serum-free medium relative to the parental melanoma cells. The suppression of growth of the hybrid cells in serum-free medium is attributable to a strict requirement of these cells for polypeptide growth factors (insulin plus platelet-derived growth factor, fibroblast growth factor, or epidermal growth factor). In contrast, the parental melanoma cells are able to grow without exogenously added growth factors. Fifteen hybrids derived from crosses between mouse L cells and normal human skin fibroblasts also have been tested for ability to grow in growth factor-unsupplemented serum-free medium. Depending on which human chromosomes are retained, growth of these hybrids in serum-free medium is also suppressed relative to growth of the L cell parent. There appear to be several genes on different chromosomes that are involved in suppression of serum-free growth of the fibroblast × L cell hybrids. One weak suppressor gene appears to be on the human X chromosome. 相似文献
7.
Teruya-Feldstein J Setsuda J Yao X Kingma DW Straus S Tosato G Jaffe ES 《Laboratory investigation; a journal of technical methods and pathology》1999,79(12):1583-1590
Hemophagocytic syndrome (HPS) is a clinicopathologic syndrome that can be precipitated by a variety of causes and is characterized by a systemic activation of macrophages, which are induced to undergo phagocytosis. Chemokines play an important role in the inflammatory cell recruitment into tissues. We examined the expression of chemokines and cytokines in tissues exhibiting histologic evidence of HPS in a variety of settings: peripheral T-cell lymphoma, three patients; nasal T/NK cell lymphoma, one patient; subcutaneous panniculitis-like T-cell lymphoma, one patient; and chronic EBV infection, one patient. Compared with control tissues, we found elevated macrophage inflammatory protein-1alpha (MIP-1alpha) and interferon-gamma (IFN-gamma) expression, but not macrophage-derived chemotactic factor (MDC) or TNF-alpha, in tissues of patients with HPS irrespective of the cause or setting. MIP-1alpha can promote macrophage chemotaxis and IFN-gamma promotes macrophage activation. Elevated expression of IP-10 and monokine induced by IFN-gamma (Mig) was also detected in tissues exhibiting features of HPS, providing an explanation for the occurrence of chemoattraction of T-cells and NK cells. Immunohistochemical analysis of tissues with evidence of phagocytic activity in that site showed MIP-1alpha characteristically localized to endothelial cells of blood vessels and splenic sinuses, lymphocytes, and macrophages. These results provide evidence for MIP-1alpha chemokine expression in tissues from patients with HPS and suggest that MIP-1alpha may play an important role in the pathogenesis of the hemophagocytic syndrome. 相似文献
8.
In recent years the literature has described a highly lethal "multicentric" variant of classic Castleman's disease (CD) with similar hyperplastic angio-follicular morphologic features. A 44-year-old man who was not known to be part of any established high-risk group for the acquired immune deficiency syndrome (AIDS) presented with clinical and laboratory features similar to "multicentric" CD. Serologic testing revealed antibody to the human immunodeficiency virus (HIV) by Western blot analysis. It is suggested that "multicentric" CD may be part of the clinicopathologic spectrum of HIV infection, and there should be a high index of suspicion for HIV in patients presenting with generalized lymphadenopathy and histopathologic features of CD. 相似文献
9.
Twenty-one of a total of 72 patients with acute pancreatitis admitted to a university hospital over a three-year period were found to have "idiopathic" pancreatitis. Of these, six nonalcoholic patients without gallbladder disease were receiving one of the thiazide diuretics prior to the onset of pancreatitis. Three patients taken from an earlier series likewise had pancreatitis associated with thiazide administration and at the time of autopsy harbored parathyroid hyperplasia. It is suggested that both the parathyroids and the pancreas may be affected by thiazide administration, and that a history of ingestion of these drugs should be sought in patients who have idiopathic pancreatitis. 相似文献
10.
Walter L Straus Edward C Mansley Karen F Gold Qin Wang Prabashni Reddy Chris L Pashos 《JPHMP》2005,11(3):244-251
OBJECTIVES: To characterize self-reported colorectal cancer (CRC) screening behavior, and to identify characteristics of CRC screening practices, stratified by risk. METHODS: Using random-digit-dial methodology, we conducted telephone surveys in US adults 50 years of age and older. Respondents provided data on utilization of CRC screening tests; demographic characteristics; and awareness, concerns, attitudes and beliefs about the tests, CRC, and health care. On the basis of available guidelines, three definitions of adequate screening were considered. RESULTS: Among persons reporting having ever had a CRC screening exam, the exam was more likely to have been a fecal occult blood test than a radiologic or endoscopic exam (p < .0001). Subjects at increased CRC risk were more likely to have met the screening criteria (p < .001) compared with average-risk subjects. Receipt of information or advice about cancer screening tests, male gender, and concern about managed care were positively associated with adequate screening. Smoking, low health self-monitoring, and an average risk for CRC reduced the probability of CRC screening. CONCLUSIONS: Lack of awareness about screening remains common, regardless of CRC risk. Providing information and advice about cancer screening may be the single most important tool available to improve screening rates. 相似文献