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61.
Giuseppe Della Porta Tommaso A. Dragani Roberto Barale Donatella Zucconi 《Journal of cancer research and clinical oncology》1984,108(3):308-311
Summary The anti-inflammatory agent diftalone was administered in the diet to male and female BALB/c mice at 300-, 600-, and 1200-ppm dose levels for 80 weeks, starting at 8 weeks of age. The animals were kept under observation until 126–128 weeks of age, when the experiment was terminated. Diftalone treatment at the highest dose was hepatotoxic and induced hepatocellular tumors in females, angiomas of the liver in males, and angiosarcomas of the liver in male and female mice. The 300- and 600-ppm dose levels were not carcinogenic. The compound was not mutagenic for Salmonella typhimurium. 相似文献
62.
Chaudhry FA Tauke JT Alessandrini RS Greenfield SA Tommaso CL Bonow RO 《Echocardiography (Mount Kisco, N.Y.)》2000,17(3):241-253
The diagnostic accuracy of dobutamine stress echocardiography is limited in patients with poor transthoracic acoustic windows. Transesophageal echocardiography (TEE) overcomes these limitations and thus may increase the clinical usefulness of dobutamine stress echocardiography. The present study was designed to compare the diagnostic accuracies of transesophageal and transthoracic dobutamine stress echocardiography for the identification of coronary artery disease (CAD) in a cohort of patients with a higher incidence of poor acoustic windows. Forty-two male patients (mean age, 66 +/- 9 years) underwent dobutamine stress echocardiography with simultaneous transesophageal and transthoracic imaging. Coronary arteriography was performed in 28 patients (67%). Transesophageal imaging adequately visualized 99.6% of left ventricular segments compared with 76.2% visualized by transthoracic imaging (P < 0.0001). There was substantial agreement between the two techniques for segmental wall motion analysis at baseline (kappa 0.76; 95% CI, 0.70-0.82); however, at peak dobutamine dose, agreement was significantly reduced (kappa 0.62; 95% CI, 0.55-0.69). The sensitivity (88% vs 75%), specificity (100% vs 75%), and positive predictive value (100% vs 80%) for the identification of CAD were all superior for transesophageal imaging. Transesophageal imaging correctly identified 11 of the 12 patients (92%) with multivessel disease compared with 5 patients (42%) identified by transthoracic imaging (P < 0.03). There were no major complications. Transesophageal dobutamine stress echocardiography is a safe, feasible, and accurate technique for the identification and risk stratification of patients with CAD. Transesophageal imaging appears to be superior to transthoracic imaging for identifying both the presence and extent of CAD, specifically in patients with poor acoustic windows. 相似文献
63.
G. Pizzolo L. Trentin F. Vinante C. Agostini R. Zambello A. Ranucci† M. Luca M. Chilosi F. Dazzi R. Foa‡ F. Caligaris-Cappio‡ G. Perona G. Semenzato 《British journal of haematology》1987,65(1):17-22
We describe a patient with acute lymphoblastic leukaemia whose blasts co-expressed immature T-cell markers and nearly the entire phenotypic repertoire of NK cells. The T-cell nature of the proliferating blasts was proven by the demonstration of the rearrangement for the beta-chain of the T-cell antigen receptor. Although an abnormal phenotypic expression related to the neoplastic proliferation cannot be formally excluded, it is possible that the cells in this patient may represent the clonal expansion of a normal subpopulation of T-cell lineage NK-related cells frozen at an early stage of differentiation. These features provide arguments for discussing the controversial issue of the ontogeny of NK cells and their relationship to the T-cell lineage. 相似文献
64.
Delirium in a patient with preexisting dementia is a common problem that may have serious complications and poor prognostic implications. The purpose of this paper was to conduct a systematic review of the medical literature on delirium superimposed on dementia, specifically to review studies on prevalence, associated features, outcomes, and management. Areas of controversy and gaps in our knowledge of this problem are highlighted. Finally, an agenda for future research is proposed. Fourteen studies were reviewed, including seven prospective studies, three retrospective studies, two cross-sectional studies, and two clinical trials. For the review of the literature on delirium superimposed on dementia, we searched MEDLINE from January 1966 through February 2002 for research studies with primary sources of data. Selection criteria for inclusion of articles in this study were inclusion of data on subjects with delirium superimposed on dementia, inclusion of a validated operational definition/measures of dementia and delirium, actual data on persons with delirium and dementia reported in the paper, and reporting of primary data. MEDLINE was searched using the following key search terms: delirium, acute confusion, cognitive impairment, Alzheimer's disease, dementia, delirium superimposed on dementia, and elderly. The prevalence of delirium superimposed on dementia ranged from 22% to 89% of hospitalized and community populations aged 65 and older with dementia. To date, only one reported study systematically identified associated factors and interventions for delirium superimposed on dementia, but several studies examining outcomes have found that adverse events are associated with delirium in persons with dementia, including accelerated and long-term cognitive and functional decline, need for institutionalization, rehospitalization, and increased mortality. This paper highlights the dearth of research on delirium superimposed on dementia and stresses the importance of early recognition and prevention of delirium in persons with dementia. 相似文献
65.
Cell apoptosis and granulomatous lung diseases 总被引:1,自引:0,他引:1
Apoptosis, also known as activation-induced cell death or programmed cell death, is an active suicide mechanism that is involved in normal tissue turnover during embryogenesis and adult life. There are many examples of apoptosis in the immune system, including programmed cell death of T cells during negative intrathymic selection of the TCR repertoire and, in the postthymic phase, death of responsive T cells upon specific activation of the TCR/CD3 complex. Induction of apoptosis assures rapid disappearance of the immune response upon antigenic clearance, avoiding the metabolic costs involved in sustaining a large number of effector cells. The knowledge that failure of immune cells to die is the cause of a number of immune-mediated disorders has opened intriguing new avenues of exploration into the pathogenetic events leading to the accumulation of immunoinflammatory cells at sites of ongoing inflammation in granulomatous disorders, including granulomas initiated by infectious agents, such as Mycobacterium tuberculosis, or in sarcoidosis. In this paper we review recent results obtained in experimental animal models and patients with immune granuloma suggesting that the positive induction by ligands binding to membrane receptors or the induction or loss of intracellular suppressor signals regulates immunoregulatory mechanisms that drive the progressive development of the granulomatous structure. The great advances in understanding how mechanisms for the activation or downregulation of apoptosis have a pathogenetic role in the outcome of granulomatous disorders are also briefly considered. 相似文献
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69.
Paulo Cceres Guido Natalia Riva Roberto Caraballo Gabriela Reyes Marina Huaman Robinson Gutierrez Silvana Agostini Sandra Fabiana Delaven Carlos A. Prez Montilla Facundo García Bournissen Paula Schaiquevich 《Epilepsia》2021,62(1):e7-e12
Growing interest in the clinical use of cannabidiol (CBD) as adjuvant therapy for pediatric refractory epileptic encephalopathy emphasizes the need for drug treatment optimization. The aim of this study was to characterize the pharmacokinetics of CBD in pediatric patients with refractory epileptic encephalopathy receiving an oil‐based oral solution. To evaluate CBD concentrations, six serial blood samples per patient were collected after the morning dose of CBD, at least 21 days after the beginning of treatment. Twelve patients who received a median (range) dose of 12.2 (5.3‐19.4) mg/kg/d (twice daily) were included in the analysis. Median (range) CBD time to maximum plasma concentration, maximum plasma concentration, and area under the concentration versus time curve up to 6 hours after dosing were 3.2 hours (1.9‐6.2), 49.6 ng/mL (14.4‐302.0), and 226.3 ng ? h/mL (70.5‐861.3), respectively. CBD systemic exposure parameters were in the lower range of previous reports in pediatric patients receiving doses in a similar range. Most of our patients (83%) showed little CBD plasma level fluctuation during a dosing interval, comparable to that encountered after oral administration of an extended release drug delivery system. CDB administration was generally safe and well tolerated, and a novel levothyroxine‐CBD interaction was recorded. Similar to other studies, large interindividual variability in CBD exposure was observed, encouraging the use of CBD therapeutic drug monitoring. 相似文献
70.
Female pelvic floor is a complex functional unit involved in multiple functions that extend beyond the sole support of pelvic organs. Pelvic floor dysfunction globally affects micturition, defecation and sexual activity. Evolutionary modifications such ad adaptation to upright standing, walking and the need to deliver fetuses with larger head diameters made the fascial and muscle support of the pelvic floor vulnerable, therefore predisposing women to pelvic organ prolapse and incontinence. Different than in males, the female pelvic floor undergoes a number of adaptive changes related to life and endocrine events. Most of the clinical manifestations of these changes become apparent after menopause and throughout aging in women. This review article summarizes the key aspects of the pathophysiology and the clinics of the modifications of the pelvic floor in women through midlife and beyond. A particular focus is given to the relationship between urinary and bowel dysfunction. 相似文献