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71.
BACKGROUND AND PURPOSE: Helical tomotherapy can eliminate the need for junction lines. The goal of this study is to evaluate tomotherapy in the delivery of CSA radiation and measurement of plan quality using physical parameters in comparing conventional (CSA-RT) and helical tomotherapy (CSA-TOMO) plans. PATIENTS AND METHODS: CSA-TOMO and CSA-RT plans were created for dosimetric comparison. Integral dose values were calculated. The ratios D50% (dose received by 50% of the organ at risk's volume) and D10% (dose received by 10% of the organ at risk's volume) were calculated representing large volumes and small volumes of organs at risk receiving significant dose. RESULTS: When considering D50% and D10%, CSA-TOMO has a dosimetric advantage over CSA-RT for most organs at risk. The body integral dose was higher for the CSA-TOMO plan by approximately 6.5%. CONCLUSIONS: Tomotherapy is a feasible alternative for treatment of CSA. Analysis shows that tomotherapy improves dose ratios over conventional radiation for most organs at risk. The impact of a small increase in whole body integral dose is unknown. Long-term follow-up will be needed to answer this question as others have argued of the possibility of increased risk of secondary malignancies due to delivery of radiotherapy with IMRT.  相似文献   
72.
Summary Reported in this paper is the first case of isolation ofPseudalle-Scheria boydii from cerebral spinal fluid of a boy with meningitis in China. Morphology and culture were observed by light microscopy, electron scanning microscopy and transmission electron microscopy. In addition, mycelium antigen prepared by SDS-PAGE was compared with that of the other strain of Scedosporium apiospermum. Both of the strains showed more than 40 peptide lines. Their molecular weight was very similar. On the CS-930 Dual-Wavelength TLC Scanner the peaks of both antigens showed to lie in nearly the same position. It could be concluded thatPseudallescheria boydii andScedosporium apiospermum belong to the same genus, but they are of different strains and reproductive phases.  相似文献   
73.
胆红素具有重要药用价值,一般用化学方法从胆汁中提取,本试验根据胆红素在人体内的代谢过程和胆结石的成因,而是利用大肠杆菌产生的β葡萄糖醛酸酶从胆汁中提取胆红素。  相似文献   
74.
Recently, a long-acting, somatostatin analogue, SMS201-995(SMS), has been developed and extensively investigated. It has been proved to be remarkably effective in treating many diseases, including active acromegaly. We observed the effect of SMS on gallbladder contractility in normal adults using the fatty meal test. Our results show that gallbladder contractility was inhibited significantly for 6 hours after the subcutaneous injection of SMS in dosages of 50, 25, 12.5, and 5 micrograms. We conclude that it is not practical to avoid gallbladder disfunction during long-term SMS treatment by decreasing the dosages of SMS.  相似文献   
75.
Mongrel or beagle dogs were submitted to bile duct ligation, or to extraenteric biliary diversion by means of choledochoureterostomy. The kinetics of intravenously administered FK506 was not changed from control status two weeks after bile duct ligation, but the bioavailability of orally administered FK506 was nearly quadrupled. Following oral administration, the absorption of FK506 was highly variable. The results indicate that in dogs FK506 is absorbed from the intestine just as efficiently in the absence of enteric bile and in presence of exogenous bile salt supplement when compared with its absorption in presence of normal bile drainage. These findings with FK506 are different from those with cyclosporine after biliary obstruction or diversion and will have important practical as well as experimental ramifications.  相似文献   
76.
This paper examines two approaches for the analysis of quantitative traits: (1) association studies and (2) linkage studies. The trait studied was Q1 from simulated Problem 2 data set in Genetic Analysis Workshop 9. Our purpose was to evaluate associations present in the data, to identify nongenetic and genetic predictors of the trait, and to explore the simulated genome for linkage. Through the association study, we found evidence for the primary major gene associated with this trait. The linkage study found evidence of residual genetic effect acting through other traits. Adjustments of Q1 for Q2 and Q3 led to a failure to find significant effects of MG2 and MG3. This supports the suggestion that adjustment for genetically influenced traits for effects of other genetic traits can reduce the power to detect major gene effects. In summary, we detected the major gene directly associated with the trait of interest through association studies. Linkage analysis detected evidence for two other genes associated to a lesser degree with the trait. © 1995 Wiley-Liss, Inc.  相似文献   
77.
王娟  朱念琼 《护理研究》2006,20(6):551-552
自身练习护理操作就是以护生作为练习对象,相互间在各自身上完成注射、输液等操作练习项目,以达到教学要求[1]。在基础护理的教学中,自身练习对于调动护生的参与感,增加真实感,满足成就感方面起着十分重要的作用。但是,也必须看到在积极效果背后的种种矛盾以及由这些矛盾可能导  相似文献   
78.
On the basis of the common occurrence of high concentration of estrogen and activated macrophages in patients with endometriosis, we postulate that interaction between 17beta-estradiol and macrophage may be an important affair in endometriosis. So our study was focused on the effect of 17beta-estradiol on macrophage. First morphology of macrophages was examined with environmental scanning electron microscopy. Increased size, extension of more microvilli, expression of retraction fibers and elaboration of membrane ruffles were detected in 17beta-estradiol treated macrophages. Then Nitrate and nitrite level in the supernatant was measured by the method of Griess and iNOS expression was analyzed using immunohistochemical staining. It showed that 17beta-estradiol could induce NO release from peritoneal macrophages and expression of iNOS was increased. Also more TNF-alpha in supernatant that was measured by MTT via L929 cell was produced by macrophages under the inducing of 17beta-estradiol. Furthermore, [Ca2+]i, which was viewed by microscope in a laser scanning confocal unit, elevated 39.8% in peritoneal macrophages after 17beta-estradiol 100 nmol/L treated. The results above demonstrated that peritoneal macrophage had been activated in both morphology and cytokine line when interaction with 17beta-estradiol, which indicated that macrophage activated by 17beta-estradiol might play a permission role in development of endometriosis.  相似文献   
79.
目的 探讨一种良好的治疗腕舟骨骨折不愈合的方法 ,丰富治疗腕舟骨骨折不愈合的手术方式。方法 切除腕舟骨骨折不愈合之硬化骨 ,以克氏针贯穿固定骨折端 ,用带骨间掌侧动脉背侧支血管蒂桡骨瓣翻转移植治疗腕舟骨骨折不愈合 15例。结果 术后随访 3~ 6个月 ,骨折完全愈合 ;9~ 18个月 ,腕关节活动正常无痛。结论 前臂间掌侧动脉背侧支解剖位置恒定 ,变异少 ,位置较表浅 ,血管蒂长、口径粗、游离安全容易 ,血供充分 ,能有效地促进舟骨骨折愈合。  相似文献   
80.
朱瑶 《英国医学杂志》2006,9(3):156-156
近期一项调查研究显示,出现勃起功能障碍的老年健康男子可能存在隐性心血管疾病。共有8063名55岁以上无心血管疾病的美国男子参加了该项队列研究,试验初始时4247人具有正常勃起功能。  相似文献   
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