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991.
OBJECTIVE: To determine whether an advance directive redesigned to meet most adults' literacy needs (fifth grade reading level with graphics) was more useful for advance care planning than a standard form (>12th grade level). METHODS: We enrolled 205 English and Spanish-speaking patients, aged >/=50 years from an urban, general medicine clinic. We randomized participants to review either form. Main outcomes included acceptability and usefulness in advance care planning. Participants then reviewed the alternate form; we assessed form preference and six-month completion rates. RESULTS: Forty percent of enrolled participants had limited literacy. Compared to the standard form, the redesigned form was rated higher for acceptability and usefulness in care planning, P相似文献   
992.
Twenty-seven edentulous patients with denture adaptation problems were first given optimal conventional complete dentures and then a fixed prosthesis on osseointegrated dental implants in the lower jaw (and a complete maxillary denture). Masticatory function was evaluated by means of a questionnaire, a comminution test for chewing efficiency, and bite force measurements on four occasions: with the original (I) and optimal complete dentures (II) and 2 months (III) and 3 years (IV) after insertion of the fixed mandibular prosthesis on implants. No significant improvement of masticatory function was found after conventional denture treatment. After insertion of the fixed mandibular implant bridge, a marked improvement of the patients' assessment of their chewing ability and of the results of the chewing efficiency test and the bite force measurements was recorded. The test results were further improved after the 3-year observation period, which indicates that adaptation to the new prosthetic situation is a gradual process.  相似文献   
993.
In eight subjects who were initially highly colonized with Streptococcus mutans and who used a 1% chlorhexidine gel, the numbers of this organism were suppressed in both plaque and saliva. Bacterial plaque samples were obtained from all tooth surfaces, and the recolonization pattern of S. mutans was studied over a 26-week period. At baseline, 83% of all surfaces harbored S. mutans with buccal surfaces colonized in higher frequency than the others. After chlorhexidine treatment, the proportion of tooth surfaces colonized by S. mutans was reduced to a low level. Re-appearance was slow. S. mutans was first recovered from the most posterior teeth in the mouth, the molar surfaces were recolonized earlier than were those of pre-molars and anterior teeth, and the buccal surfaces were recolonized more readily than were the other tooth surfaces. The data show that there is a specific recolonization pattern of S. mutans after chlorhexidine treatment, and that the re-emergence of S. mutans is most probably due to regrowth of bacteria which have not been eradicated.  相似文献   
994.
目的:探讨在大鼠脑缺血的情况下经尾静脉注射移植骨髓基质细胞的可行性,为骨髓基质细胞脑移植治疗提供一种简捷、安全、有效的途径。方法:实验于2005-10/2006-08在北华大学医学院实验中心完成。取1~2个月龄SD大鼠双侧股骨和胫骨,体外分离培养大鼠骨髓基质细胞。取体质量为280~320g的SD大鼠25只,采用颈内动脉线栓法制作大脑中动脉梗死模型,造模成功后在25只大鼠中随机盲抓分为2组:骨髓基质细胞移植组(n=15)、对照组(n=10)。骨髓基质细胞移植组经静脉缓慢推入含Hoeschst33342标记的骨髓基质细胞细胞悬液1mL(2.0×107个细胞),对照组用同样方法经尾静脉注入等量不含骨髓基质细胞的DMEM培养液作为对照。分别于移植后1d、7d、14d时间点对两组大鼠进行神经功能损害严重程度评分及大脑组织切片观察比较。结果:25只大鼠均进入结果分析。①各代细胞90%以上表达巢蛋白阳性。②与对照组相比,骨髓基质细胞移植组大鼠运动、神经功能恢复明显[骨髓基质细胞移植组:(6.10±2.96),(3.30±1.83),(2.10±1.20)分;对照组:(7.43±1.51),(6.14±1.35),(4.43±1.40)分,P<0.05]。③骨髓基质细胞移植组大鼠脑组织结构较清晰、完整;对照组大鼠脑组织破坏溶解,组织结构松散,细胞结构不完整,胞浆疏松,染色变浅,间质水肿。结论:通过静脉注射进行骨髓基质细胞移植,方法简便、安全,对神经损伤动物组织重建及神经功能有确切的修复效果。  相似文献   
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998.
We have recently described an immunoregulatory mechanism involving release of neutralizing autoantibodies (Aab) to cytokines during bacterial infections. Intraperitoneal inoculation of Haemophilus influenzae type b (Hib) into Sprague-Dawley rats resulted in high levels of inflammatory mediators early after infection. Increased titers of cytokine Aab were observed, with a peak at day 7. We cloned Aab-producing B cells. Screening of the clones with five different cytokines resulted in detection of Aab-producing clones reactive with each cytokine. After repeated subcloning, monoclonal Aab (mAab) were selected and characterized for their specificity, isotypes, and affinities. To elucidate regulatory importance, mAab to interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha) dose-dependently inhibited IFN-gamma-induced MHC expression by peritoneal macrophages and TNF-alpha-induced thymocyte proliferation, respectively. Fab fragments exhibited binding and neutralizing effects, confirming specificities. Cross-reactivity with other rat cytokines was excluded. Pools of clones containing several mAab to each cytokine were obtained and served as polyclonal Aab. The relative affinity of the Aab was determined and found to be of high index. The characterized Aab were tested in methodologic assays for cytokine detection, revealing that some Aab were useful in a cell release capturing (CRC) ELISA.  相似文献   
999.
The metabolism of Ba140 has been studied in seven subjects with normal skeletal metabolism and in one subject with vitamin D resistant rickets by serial sampling of serum, urine and stools over a 7 to 14 day period following parenteral administration of Ba140 (half life 12.8 days).

The values of the accretion rate of bone salt calculated from Ba140 data were higher than those calculated from Ca45 data under the same experimental conditions.

In the case with vitamin D resistant rickets the accretion rate of hone salt as calculated from the Ba140 data was probably normal. After treatment with massive doses of vitamin D the accretion rate rose to values significantly higher than normal.

Since there seems to be no fundamental difference in the metabolism of Ba140 and Ca140, Ba140 should be suitable for use as an indicator of skeletal metabolism in humans.  相似文献   
1000.
We determined whether serum cystatin C, a novel measure of kidney function that colocalizes with brain beta-amyloid, is associated with cognition among 3,030 elders. Those with high cystatin C (n = 445; 15%) had worse baseline scores on Modified Mini-Mental State Examination or Digit Symbol Substitution Test (p or=1.0 standard deviation) was greatest among those with high cystatin C (Modified Mini-Mental State Examination: 38 vs 25%; adjusted odds ratio, 1.92; 95% confidence interval, 1.37-2.69; Digit Symbol Substitution: 38 vs 26%; odds ratio, 1.54; 95% confidence interval, 1.10-2.15).  相似文献   
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