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1.
A novel balanced SSFP technique for the separation or suppression of different resonance frequencies (e.g., fat suppression) is presented. The method is based on applying two alternating and different repetition times, TR(1) and TR(2). This RF scheme manipulates the sensitivity of balanced SSFP to off-resonance effects by a modification of the frequency response profile. Starting from a general approach, an optimally broadened stopband within the frequency response function is designed. This is achieved with a TR(2) being one third of TR(1) and an RF-pulse phase increment of 90 degrees . With this approach TR(2) is too short ( approximately 1 ms) to switch imaging gradients and is only used to change the frequency sensitivity. Without a significant change of the spectral position of the stopband, TR(1) can be varied over a range of values ( approximately 2.5-4.5 ms) while TR(2) and phase cycling is kept constant. On-resonance spins show a magnetization behavior similar to balanced SSFP, but with maximal magnetization at flip angles about 10 degrees lower than in balanced SSFP. The total scan time is increased by about 30% compared to conventional balanced SSFP. The new technique was applied on phantoms and volunteers to produce rapid, fat suppressed images. 相似文献
2.
Objective. To determine if patients treated at hospitals under different levels of financial strain from the Balanced Budget Act (BBA) of 1997 had differential changes in 30-day mortality, and whether vulnerable patient populations such as the uninsured were disproportionately affected.
Data Source. Hospital discharge data from all general acute care hospitals in Pennsylvania from 1997 to 2001.
Study Design. A multivariate regression analysis was performed retrospectively on 30-day mortality rates, using hospital discharge data, hospital financial data, and death certificate information from Pennsylvania.
Data Collection. We used 370,017 hospital episodes with one of four conditions identified by the Agency for Healthcare Research and Quality as inpatient quality indicators were extracted.
Principal Findings. The average magnitude of Medicare payment reduction on overall net revenues was estimated at 1.8 percent for hospitals with low BBA impact and 3.6 percent for hospitals with a high impact in 1998, worsening to 2 and 4.8 percent, respectively, by 2001. Operating margins decreased significantly over the time period for all hospitals ( p <.05). While unadjusted mortality rates demonstrated a disproportionate rise in mortality for patients from high impact hospitals from 1997 to 2000, adjusted analyses show no consistent, significant difference in the rate of change in mortality between high-impact and low-impact hospitals ( p =.04–.94). Similarly, uninsured patients did not experience greater increases in mortality in high-impact hospitals relative to low-impact hospitals.
Conclusions. An analysis of hospitalizations in the Commonwealth of Pennsylvania did not find an adverse impact of increased financial strain from the BBA on patient mortality either among all patients or among the uninsured. 相似文献
Data Source. Hospital discharge data from all general acute care hospitals in Pennsylvania from 1997 to 2001.
Study Design. A multivariate regression analysis was performed retrospectively on 30-day mortality rates, using hospital discharge data, hospital financial data, and death certificate information from Pennsylvania.
Data Collection. We used 370,017 hospital episodes with one of four conditions identified by the Agency for Healthcare Research and Quality as inpatient quality indicators were extracted.
Principal Findings. The average magnitude of Medicare payment reduction on overall net revenues was estimated at 1.8 percent for hospitals with low BBA impact and 3.6 percent for hospitals with a high impact in 1998, worsening to 2 and 4.8 percent, respectively, by 2001. Operating margins decreased significantly over the time period for all hospitals ( p <.05). While unadjusted mortality rates demonstrated a disproportionate rise in mortality for patients from high impact hospitals from 1997 to 2000, adjusted analyses show no consistent, significant difference in the rate of change in mortality between high-impact and low-impact hospitals ( p =.04–.94). Similarly, uninsured patients did not experience greater increases in mortality in high-impact hospitals relative to low-impact hospitals.
Conclusions. An analysis of hospitalizations in the Commonwealth of Pennsylvania did not find an adverse impact of increased financial strain from the BBA on patient mortality either among all patients or among the uninsured. 相似文献
3.
课题研究提供了改良的人精子染色体直接制备,G显带核分析技术。在对80例对象的人精子染色体直接制备,G显带核型分析中,成功率为62.5%,较Templado方法的成功率(58.1%)进一步提高。通过对正常人,不育,流产对象的男性精子染色体研究,发现精子染色体数目和结构畸变率分别为:正常人2.3%和0%,不育14.0%和4.8%,流产组4.5%和2.4%,不育和流产组的畸变率较正常人增加。在对5例染色 相似文献
4.
苏爱 《中国优生与遗传杂志》2004,12(3):43-44
目的与方法本文对189例自然流产、闭经、发育不全患者进行细胞遗传学检查,结果发现异常核型16例,异常核型涉及1、3、4、5、6、7、8、9、10、 15、X、Y染色体.其中平衡易位10例,性染色体异常3例,大Y染色体3例.结论染色体异常是导致流产、闭经、性发育异常的重要遗传因素,应引起临床医师的高度重视. 相似文献
5.
L. Hübner E.M. Kniep H. Laukel C. Sorg H. Fischer W.D. Gassel K. Havemann B. Kickhöfen M.-L. Lohmann-Matthes A. Schimpl E. Wecker 《Immunobiology》1980,157(2):169-178
Supernatants from Concanavalin A-stimulated murine spleen cells were subjected to hydrophobic interaction chromatography on phenyl-Sepharose. Macrophage cytotoxicity factor (MCF), macrophage migration inhibitory factor (MIF), T-helper cell-replacing factor (TRF) and colony-stimulating factor (CSF) were bound at high ionic strength and were released stepwise at low ionic strength. CSF thus could be separated from MCF, MIF and TRF and the bulk of other proteins. Chromatography of pools containing MCF, MIF and TRF on Sephadex did not lead to a separation of the three activities which were all found in a molecular weight range of 25.000-55.000. Isoelectric focusing of these pools in pH range from 4 to 9 gave two peaks for MCF at pH 8.2 and 7.2, whereas MIF activity focused from pH 4.5 to 5.5. TRF activity was found in a single sharp peak at pH 5.3. The results demonstrate that the four biological activities can be distinguished on a chemical basis and are accessible for purification and chemical characterization. 相似文献
6.
李琳 《中国生育健康杂志》2006,17(2):96-98
目的探讨染色体平衡易位与异常孕产的关系。方法采用外周血淋巴细胞培养和染色体G显带分析,对612对有异常孕产史的夫妇进行染色体检查。结果染色体平衡易位携带者检出率为3.3%(41/1 224),其中常染色体相互易位占58.5%(24/41),罗伯逊易位占39.0%(16/41),嵌合易位占2.4%(1/41)。9例为世界首报染色体异常核型,分别为:46,XY,t(11;12)(q13;q21);46,XX,t(3;20) (qll;q11);46,XX,t(15;16)(pll;q13);46,XY,t(2;14)(p16;q31);46,XY,t(4;10)(q25;p15);46,XX,t(3;8) (p26;q11);46,XY,t(6;16)(q15;p13);46,XX,t(18;22)(p10;q10);46,XY,t(18;22)(p10;q10)mat。总妊娠127次,早期妊娠流产率为86.6%(110/127)。结论染色体平衡易位携带者的异常孕产以早期妊娠自然流产为主要表现。 相似文献
7.
目的探讨躯干核心肌群训练的强度对脑卒中患者躯干控制、平衡步行及日常生活能力的康复效果。方法选择2017年4月至2018年3月在华中科技大学同济医学院附属协和医院康复医学科住院治疗的90例脑卒中偏瘫患者为研究对象,按照随机数字表法将患者分为A、B、C组,每组各30例,3组患者均在常规治疗基础上联合不同强度的躯干核心肌群训练,其中A组每天训练1次,B组每天训练2次,C组每天训练3次,每次训练30 min,每周5天,共训练3个月。3组患者治疗1个月、2个月和3个月时采用躯干控制能力测试(TCT)、Berg平衡量表(BBS)评价躯干控制能力,采用步行功能评级(FAC)评定平衡步行功能、采用日常生活能力(MBI)评定日常生活能力。比较3组患者上述评分差异。结果治疗前3组患者躯干控制能力、平衡步行功能和生活能力评分比较差异无统计学意义(P> 0. 05),3组患者治疗1个月、2个月、3个月后躯干控制、平衡步行和日常生活能力评分均逐渐提高,差异均有统计学意义(P均<0. 05);且在1~3个月期间躯干控制和平衡能力评分C组高于B组,B组高于A组,差异均有统计学意义(P均<0. 05),但3个月时差异无统计学意义(P> 0. 05)。3组患者步行和日常生活能力在1个月期间组间差异无统计学意义(P> 0. 05),但1个月后C组较B组,B组较A组均有统计学意义(P均<0. 05)。结论强化躯干核心肌力量可以显著提高患者躯干控制、平衡步行和日常生活能力,缩短康复时间。 相似文献
8.
9.
目的:观察氟哌利多穴位注射对妇科腹腔镜手术后恶心呕吐的影响。方法:将60例妇科腹腔镜手术患者以随机数字表法分为A组(n=30)和I组(n=30)。 A组患者在诱导前10 min于双侧内关穴注射氟哌利多1 mg,I组患者在诱导前10 min静脉注射氟哌利多2 mg。记录患者术毕至拔气管导管时间、术毕至听从指令时间、术后24 h内恶心呕吐发生率及严重程度。结果:A组患者术后0~1、1~2、2~4、4~12 h的恶心呕吐评分( NVS评分)低于I组,麻醉后监测治疗室内给予止吐药的病例数少于I组(P均<0.05)。2组患者术后12~24 h的NVS评分、拔管时间、听从指令时间的差异无统计学意义(P>0.05)。结论:氟哌利多穴位注射预防妇科腹腔镜手术后恶心呕吐的效果优于静脉注射氟哌利多,且不影响麻醉恢复。 相似文献
10.
目的 利用平衡致死系统构建表达O157:H7 EspA 的减毒鼠伤寒沙门氏菌.方法 构建表达EspA的重组质粒,再将其转入终宿主菌减毒鼠伤寒沙门氏菌x4550 株中构建成口服活疫苗株,用IPTG进行诱导表达,经聚丙烯酰胺凝胶电泳、Westen-blot检测EspA蛋白的表达情况.并观察重组菌体外培养的稳定性.结果 利用宿主-载体平衡致死系统构建了表达O157:H7 EspA的重组减毒沙门氏菌,经Tricine-SDS-PAGE电泳出现了1条Mr约21 000的蛋白条带,Westen-blot检测能与抗EspA的单克隆抗体发生特异性反应.且在没有选择压力的条件下体外能稳定地繁殖、生长和传代.结论 表达O157:H7 EspA的重组减毒沙门氏菌构建成功,为发展口服抗EHEC O157:H7的疫苗奠定了初步基础. 相似文献