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1.
独活种子发芽特性研究   总被引:7,自引:1,他引:7  
王康才  陈暄  唐晓清  兰才武 《中草药》2005,36(4):595-597
目的探讨独活种子的发芽率低的原因,以及适宜发芽条件,为大田生产奠定基础。方法采用去果皮、清水以及GA浸种等方法处理种子,在不同的温度和光照条件下,检测种子的发芽情况。结果清水浸种24h可提高发芽率13.7%,去果皮可提高种子发芽率10.6%;在浸种24h条件下,与暗培养相比,光照可提高发芽率16.6%;适宜发芽温度为20℃,高温对独活种子萌发具有抑制作用。结论独活种子中存在发芽抑制物质,光照可促进种子发芽。  相似文献   
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An innovative method to structure multidisciplinary team conferences in rehabilitation medicine was developed: Rehabilitation Activities Profile report system (RAP-TEAM). Experiences with introduction of RAP-TEAM and the study of its effects on the satisfaction of professionals are described. RAP-TEAM was introduced in three teams. RAP-TEAM did not influence the satisfaction of professionals in two teams; satisfaction in the third team even decreased. Nevertheless, professionals report more benefits than disadvantages of RAP-TEAM. Several possible explanations for these results and the methodological problems with this kind of evaluation study are discussed. The most important explanation is that introduction of an innovative method should be allowed sufficient time before it could become effective. Recommendations for a successful introduction of innovative changes are made. All people concerned must be aware that a process of change is not simple, and needs the full attention of all.  相似文献   
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The growth factor heregulin (HRG) promotes breast cancer (BC) tumorigenesis and metastasis and differentially modulates BC cell responses to DNA-damaging agents via its dual extracellular and nuclear localization. Given the central role of telomere dysfunction to drive carcinogenesis and to alter the chemotherapeutic profile of transformed cells, we hypothesized that an unanticipated nuclear function of HRG might be to regulate telomere length. Engineered overexpression of the HRGβ2 isoform in non-aggressive, HRG-negative MCF-7 BC cells resulted in a significant shortening of telomeres (up to 1.3 kb) as measured by Southern blotting of telomere terminal restriction fragments. Conversely, antisense-mediated suppression of HRGβ2 in highly aggressive, HRG-overexpressing MDA-MB-231 and Hs578T cells increased telomere length up to 3.0 kb. HRGβ2 overexpression promoted a marked upregulation of telomere-binding protein 2 (TRF2) protein expression, whereas its knockdown profoundly decreased TRF2 expression. Double staining of endogenous HRGβ2 with telomere-specific peptide nucleic acid probe/fluorescence in situ hybridization (PNA/FISH) revealed the partial localization of HRG at the chromosome ends. Moreover, a predominantly nucleoplasmic staining pattern of endogenous HRGβ2 appeared to co-localize with TRF2 and, concomitantly with RAP1, a telomere regulator that specifically interacts with TRF2. Small interfering RNA-mediated knockdown of HRG decreased the expression of TRF2 and RAP1, decreased their presence at chromosome ends, and coincidentally resulted in the formation of longer telomeres. This study uncovers a new function for HRGβ2 in controlling telomere length, in part due to its ability to regulate and interact with the telomere-associated proteins TRF2 and RAP1.  相似文献   
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Recycling of reclaimed asphalt pavement (RAP) has gradually emerged as a hot topic in the current research of building materials. Manufacturing the recycled asphalt mixture with a high RAP content still remains a major challenge due to the problem of inferior water damage resistance and fatigue cracking resistance. The aim of this study is to evaluate the servicing performance of recycled asphalt mixture with high percentage of RAP and assess its environmental impact on volatile organic compounds (VOCs) emission. To further explore the intrinsic factor on the performance of a recycled asphalt mixture, the mixed asphalt binder with a different content of extracted RAP binder was firstly investigated. The results show that the larger the content of RAP binder, the lower the mechanical indexes and VOCs emission. There exists an internal relationship between the chemical composition and VOCs release behavior with the variation of the recycled asphalt binder content. Based on the results of mixed recycled asphalt binder, the road servicing performance of a rather high utilization of RAP (i.e., 50%, 60%, and 70%) was assessed. It was found that the reuse of RAP aggregates has little influence on the volume performance of recycled asphalt mixture, and servicing performances still meet the construction requirements in spite of a descending trend. Moreover, a significant reduction effect on VOCs emission was found in the mixing stage of recycled asphalt mixture, indicating that the VOCs emission can be decreased by 94.82% when the content of RAP aggregates increases to 70%. The recycling of RAP with a high content contributes to the sustainable development of road engineering and the construction of green pavements.  相似文献   
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ObjectiveTo examine the frequency and outcomes of patients requiring renal replacement therapy (RRT) early after left ventricular assist device (LVAD) implantation.Patients and MethodsWe examined use of in-hospital RRT and outcomes in consecutive adults who underwent continuous-flow LVAD implantation from February 15, 2007, through August 8, 2017. Logistic regression was used to examine predictors of RRT. The associations of RRT with outcomes were examined using Cox proportional hazards regression.ResultsOf 354 patients who underwent LVAD implantation, 54 (15%) required in-hospital RRT. Patients receiving RRT had higher preoperative Charlson Comorbidity Index values (median, 5 vs 4; P=.03), Model for End-Stage Liver Disease scores (mean, 19.0 vs 14.5; P<.001), right atrial pressure (mean, 19.1 vs 13.4 mm Hg; P<.001), and estimated 24-hour urine protein levels (median, 357 vs 174 mg; P<.001) and lower preoperative estimated glomerular filtration rate (eGFR) (median, 43 vs 57 mL/min; P<.001) and measured GFR using 125I-iothalamate clearance (median, 33 vs 51 mL/min; P=.001) than those who did not require RRT. Approximately 40% of patients with eGFR less than 45 mL/min/1.73 m2 and 24-hour urine protein level greater than 400 mg required RRT vs 6% with eGFR greater than45 mL/min/1.73 m2 and without significant proteinuria. Lower preoperative eGFR, higher estimated 24-hour urine protein level, higher right atrial pressure, and longer cardiopulmonary bypass time were independent predictors of RRT after LVAD implantation. Of patients requiring in-hospital RRT, 18 (33%) had renal recovery, 18 (33%) required outpatient hemodialysis, and 18 (33%) died before hospital discharge. After median (Q1, Q3) follow-up of 24.3 (8.9, 49.6) months, RRT was associated with increased risk of death (adjusted hazard ratio [HR], 2.86; 95% CI, 1.90-4.33; P<.001) and gastrointestinal bleeding (adjusted HR, 4.47; 95% CI, 2.57-7.75; P<.001).ConclusionIn-hospital RRT is associated with poor prognosis after LVAD. A detailed preoperative assessment of renal function before LVAD may be helpful in risk stratification and patient selection.  相似文献   
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Background To evaluate the two-year efficacy of photodynamic therapy with Visudyne (PDT) in neovascular age-related macular degeneration (AMD) eyes with chorioretinal anastomosis (CRA). Methods A non-randomized, institutional, prospective study, of 28 consecutive eyes of 23 patients, with CRA, treated with PDT. Masked best corrected visual acuity (VA) and angiographic features at baseline and during the period of two years were evaluated. Results Twenty eight eyes completed one year and 19 eyes completed two years of follow-up. The number of treatments was 3 in the first year, and 0.8 in the second year. A VA loss < 3 lines occurred in 53% of the eyes, at two years. Treated eyes lost 0.5 lines in the first year and 2.4 lines in the second (p < 0,01). Recurrence with additional significant VA loss occurred in four eyes (21%) during the second year. Fourteen eyes (74%) showed no fluorescein leakage at two years. Conclusion AMD eyes with chorioretinal anastomosis can benefit from PDT with Verteporfin at two years. However, during the second year significant additional VA loss occurs mainly due to recurrence. New modalities of treatment are necessary to achieve VA improvement in CRA eyes.  相似文献   
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本文总结了年龄相关性黄斑变性的特殊类型—视网膜血管瘤增殖(RAP)的临床和造影表现及分期。RAP是起源于黄斑旁视网膜深层毛细血管的、以伴发多灶小片视网膜内出血及盘变前期即有视网膜-脉络膜血管吻合(RCA)形成为特征的新生血管性AMD。  相似文献   
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