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51.
52.
Reactions to contrast media: testing the CNS hypothesis 总被引:1,自引:0,他引:1
53.
Sylvia AF Peters Eefje H Grievink Wim HJ van Bon John HL van den Bercken AnneGM Schilder 《Developmental medicine and child neurology》1997,39(1):31-39
A cohort of 946 children who were screened for otitis media with effusion (OME) from the ages of 2 to 4 were studied for language, reading, and spelling at 7 years of age. The effects of OME in combination with single risk factors and with increasing numbers of risk factors were investigated. An interaction with an additional risk factor was found only for gender and OME, with boys' spelling influenced negatively by a history of OME. OME in combination with preterm birth and low birthweight also appears to put children at risk for later langauage and educational problems. Although a negative linear relation between the number of risk factors and later functioning was found, it is suggested that OME, even when combined with a number of other risk factors, produces only minor effects on later language, reading, and spelling. 相似文献
54.
vanSonnenberg E; Casola G; Zakko SF; Varney RR; Cox J; Wittich GR; Hofmann AF 《Radiology》1988,169(2):505-509
The authors describe percutaneous treatment of gallbladder or bile duct stones in 18 patients who were poor surgical candidates or in whom conventional therapy failed. Dissolution was performed in most cases with methyl tert-butyl ether (MTBE) because of its potent dissolution properties; other solvents used included monooctanoin or chelating solutions. Gallbladder stones were eliminated in 11 of 13 patients (six of seven with dissolution alone, four of four with dissolution and basket extraction, one with basket removal alone). In five patients with stones in the common bile duct (n = 3), cystic duct remnant (n = 1), and intrahepatic bile ducts (n = 1), stones were eliminated with dissolution alone in two and with dissolution plus basket extraction in one. In two patients percutaneous therapy failed due to complications (vagal hypotension with bile peritonitis and transient respiratory arrest) that occurred during catheter placement. Preliminary results suggest that MTBE is effective for dissolution of many gallbladder stones and some bile duct stones. Noncholesterol solvents and adjuvant mechanical maneuvers are valuable adjuncts to achieve complete stone elimination. 相似文献
55.
56.
MR Afify Abd El-Moneim S Ali Fatma AF Turky 《Asian Pacific Journal of Tropical Biomedicine》2012,2(1):24-30
Objective
To evaluate the acaricidal activity of extracts of three essential oils of chamomile, marjoram and Eucalyptus against Tetranychus urticae (T. urticae) Koch.Methods
Extracts of three essential oils of chamomile, marjoram and Eucalyptus with different concentrations (0.5%, 1.0%, 2.0%, 3.0% and 4.0%) were used to control T. urticae Koch.Results
The results showed that chamomile (Chamomilla recutita) represented the most potent efficient acaricidal agent against Tetranychus followed by marjoram (Marjorana hortensis) and Eucalyptus. The LC50 values of chamomile, marjoram and Eucalyptus for adults were 0.65, 1.84 and 2.18, respectively and for eggs 1.17, 6.26 and 7.33, respectively. Activities of enzymes including glutathione-S-transferase, esterase (α-esterase and β-esterase) and alkaline phosphatase in susceptible mites were determined and activities of enzymes involved in the resistance of acaricides were proved. Protease enzyme was significantly decreased at LC50 of both chamomile and marjoram compared with positive control. Gas chromatography-mass spectrometer (GC-MS) proved that the major compositions of Chamomilla recutita are α-bisabolol oxide A (35.251%), and trans-β-farersene (7.758%), while the main components of Marjorana hortensis are terpinene-4-ol (23.860%), p-cymene (23.404%) and sabinene (10.904%).Conclusions
It can be concluded that extracts of three essential oils of chamomile, marjoram and Eucalyptus possess acaricidal activity against T. urticae. 相似文献57.
胸腺肽α1(Tα1)为一种免疫调节多肽,可增强效应T细胞反应。此项大型随机试验主要评价了Tα1与达卡巴嗪(DTIC)和干扰素α(IFN—α)对于转移性黑色素瘤患者的疗效和安全性。 相似文献
58.
José F. Costa Ricardo Fontes-Carvalho Adelino F. Leite-Moreira 《Revista portuguesa de cardiologia》2013,32(11):893-904
Short periods of myocardial ischemia followed by reperfusion induce a cardioprotective mechanism when the myocardium is subsequently subjected to a prolonged period of ischemia, a phenomenon known as ischemic preconditioning.As well as its application in the myocardium, ischemic preconditioning can also be induced by brief interruptions of blood flow to other organs, particularly skeletal muscle. Transient ischemia induced noninvasively by inflating a cuff on a limb, followed by reperfusion, helps reduce the damage caused to the myocardium by interruption of the coronary circulation.Remote ischemic preconditioning involves activation of humoral and/or neural pathways that open mitochondrial ATP-sensitive potassium channels in the myocardium and close mitochondrial permeability transition pores, making cardiomyocytes less vulnerable to ischemia-induced cell death.This cardioprotective mechanism is now being translated into clinical practice, with positive results in several clinical trials in coronary artery bypass surgery, surgical repair of abdominal aortic aneurysms, valve replacement surgery and percutaneous coronary intervention. However, certain factors weaken the subcellular mechanisms of preconditioning - age, comorbidities, medication, anesthetic protocol - and appear to explain the heterogeneity of results in some studies.Detailed understanding of the pathways involved in cardioprotection induced by ischemic preconditioning is expected to lead to the development of new drugs to reduce the consequences of prolonged ischemia. 相似文献
59.
Haemodynamic and neuroendocrine effects of tezosentan in chronic experimental pulmonary hypertension
Lourenço AP Vasques-Nóvoa F Oliveira-Pinto J Fontoura D Roncon-Albuquerque R Leite-Moreira AF 《Intensive care medicine》2012,38(6):1050-1060
Purpose
Chronic pulmonary hypertension (PH) therapy is poorly investigated in intensive care. Our aim was to evaluate haemodynamic and neuroendocrine effects of the dual endothelin-1 (ET-1) blocker tezosentan in monocrotaline (MCT)-induced PH.Methods
Male Wistar rats (180–200?g, n?=?194) randomly received 60?mg?kg?1 MCT or vehicle, subcutaneously, and 2?days later, a subgroup of MCT-injected rats was gavaged with 300?mg?kg?1?day?1 bosentan (MCT BOS, n?=?46), while another (MCT, n?=?125) and control rats (Ctrl, n?=?23) received vehicle. At 25–30?days, 48?h after interrupting bosentan, rats randomly underwent either a dose–response evaluation (0.5–20?mg?kg?1, n?=?7 each group) or a 4?h perfusion of tezosentan (20?mg?kg?1 in 10?min?+?10?mg?g?1?h?1) or vehicle (n?=?8 per group, each). Haemodynamics, including blood gas analysis, were evaluated after thoracotomy under anaesthesia. After plasma, right ventricle (RV) and lung collection, plasma ET-1, cytokines, nitrate and 6-keto-PGF1α, and lung and right ventricular gene expression and cyclooxygenase (COX) and nitric oxide synthase (NOS) activities were quantified.Results
Monocrotaline resulted in PH, RV dilation and decreased cardiac output (CO) that were attenuated in MCT BOS. Pulmonary hypertension was attenuated by tezosentan without systemic hypotension. Tezosentan increased CO without changing ventilation-perfusion matching. Both bosentan and tezosentan reduced ET-1 and cytokine plasma levels and tissue expression, and inducible NOS and COX-2 RV activities. Bosentan increased nitrate plasma levels and non inducible NOS activities whereas tezosentan decreased circulating 6-keto-PGF1α but increased lung COX-1 activity.Conclusions
Tezosentan may be useful for haemodynamic handling and bosentan replacement in critically ill PH patients exerting important beneficial neuroendocrine and anti-inflammatory actions. 相似文献60.