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排序方式: 共有371条查询结果,搜索用时 15 毫秒
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Reactions to contrast media: testing the CNS hypothesis 总被引:1,自引:0,他引:1
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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
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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
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We performed a treatment planning study in order to gather basic insight in the effect of setup errors and breathing motion on the cumulative proton dose to a lung tumor. We used a simplified geometry that simulates a 50 mm diameter gross tumor volume (GTV) located centrally inside lung tissue. The GTV was expanded with a uniform 5 mm margin into a clinical target volume (CTV) and into a variety of planning target volume (PTV's). Proton beam apertures were designed to conform the prescribed dose laterally to the PTV while the range compensator was designed to provide distal coverage of the CTV. Different smearing distances were applied to the range compensators, and the cumulative dose in the CTV was evaluated for different combinations of breathing motion and systematic setup errors. Evaluation parameters were the dose to 99% of the CTV (D99) and the equivalent uniform dose (EUD), with a surviving fraction at 2 Gy of SF2 = 0.5. For a single proton field designed to a 15 mm expansion of the CTV and without smearing applied to the range compensator, D99 of the CTV reduced from 96% for no tumor displacement to 41% and 13% for systematic setup errors of 5 and 10 mm, respectively. For a representative clinical combination, of 5 mm systematic error and 10 mm breathing amplitude, the EUD of the CTV was about 40 Gy (prescribed dose 70 Gy) regardless the CTV to PTV margin, and without smearing. Smearing the range compensator increases the dose to the CTV substantially with a lateral margin and smearing distance of 7.5 mm providing ample tumor coverage. In this latter case, D99 of the target volume increased to 87% for a single field treatment plan. Smearing does, however, lead to an increase in dose to normal tissues distal to the clinical target volume. Next to countering geometric mismatches due to patient setup, smearing can also be used to counter the detrimental effects of breathing motion on the dose to the clinical target volume. We show that the lateral margin and smearing distance can be substantially smaller than the maximum tumor displacement due to setup errors and patient breathing, as measured by the D99 and the EUD. 相似文献
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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49.
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
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