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排序方式: 共有776条查询结果,搜索用时 15 毫秒
1.
目的:研究心脏康复运动对冠脉支架植入术后患者血脂、血糖、体重指数及生活质量的影响。方法:对实施冠脉支架植入术的
146例患者进行比较分析,根据随机原则分为试验组76 例及对照组70 例。对照组患者给予常规的健康教育及冠心病二级预防指
导,给予定期随访。试验组患者在此基础上给予规律的康复运动指导。经过6 个月随访,比较两组患者血脂、HbA1C、体重指数及
生活质量情况。结果:试验组患者通过为期6 个月的规律的心脏康复运动指导,其血脂、HbA1C等冠心病危险因素控制情况优于
对照组,差异有统计学意义(P<0.05)。同时,6个月后,试验组康复运动六月后sF 量表各项评分与对照组同期比较,差异均有统计
学意义(P<0.05)。结论:规范的心脏康复运动指导能够有效改善冠脉支架植入术后患者血脂、血糖情况,提高患者生活质量。 相似文献
2.
The presence of litter has the potential to alter the population dynamics of plants. In this paper, we explore the effects
of litter on population dynamics using a simple experimental laboratory system with populations of the annual crucifer, Cardamine pensylvanica. Using a factorial experiment with four densities and three litter levels, we determined the effect of litter on biomass
and plant fecundity, and the life stages responsible for these changes in yield. Although litter had significant effects on
seed germination and on seedling survivorship, we show, using a population dynamics model, that these effects were not demographically
significant. Rather, the potential effect of litter on population dynamics resulted almost entirely from its effect on biomass.
Persistent litter suppressed plant biomass and apparently removed the direct density effect present in the absence of litter.
Thus, litter changed the shape of the recruitment curve from slightly humped to asymptotic. In addition to changing the shape
of the recruitment curve, litter reduced the carrying capacity of the populations. Thus, the population dynamics model indicated
that not all statistically significant responses were dynamically significant. Given the potential complexity of litter effects,
simple population models provide a powerful tool for understanding the potential consequences of short-term responses.
Received: 8 September 1999 / Accepted: 5 April 2000 相似文献
3.
†M. J. Blanco-Príeto C. Durieux V. Daugé †E. Fattal †P. Couvreur B. P. Roques 《Journal of neurochemistry》1996,67(6):2417-2424
Abstract: Neuropeptides have been shown to play a critical role in adaptational processes, probably by long-term modulation of neuronal pathways. It could therefore be interesting to study behavioral changes induced by chronic local stimulation of neuropeptide receptors. With this aim poly(lactide-co-glycolide) microspheres loaded with a highly potent, peptidase-resistant, cholecystokinin (CCK)-B-selective CCK peptidomimetic agonist (pBC 264) were prepared by a water in oil in water emulsion solvent evaporation method and stereotaxically implanted into the anterior part of the rat nucleus accumbens. Two different kinds of loaded polymeric microspheres differing only by the stabilizing agent [ovalbumin (OVA) or Pluronic F 68] added to the inner emulsion were used. The histological and behavioral studies done 24 h and 8 days after implantation of nonloaded microspheres in the nucleus accumbens indicated that the microspheres were well tolerated. The in vivo release of the selective CCK-B agonist pBC 264 (associated with a tracer dose of [3 H]pBC 264) from microspheres prepared with OVA was very fast (92% after 6 h), whereas only 26% (88 pmol) of pBC 264 was released from the formulation with Pluronic F 68 after 24 h. Eight days after implantation 36% of pBC 264 had diffused from the microspheres, and 8% (∼30 pmol) was still present in the brain concentrated around the site of administration. In all cases the released material was found to correspond to intact pBC 264, thus demonstrating the possibility of obtaining a slow controlled release of peptide in vivo. This method opens up interesting perspectives to study the long-term effects of neuropeptides. 相似文献
4.
Li Shichang Zhang Pengpeng Gu Shaobin Liu Hongxia Liu Ya Liu Shengnan 《Indian journal of microbiology》2013,53(3):343-351
In order to obtain lipid producing strain with high-yield, the wild type stain Rhodotorula glutinis was treated by low ion implantation, and optimization of fermentation medium for higher lipid yield was carried out using mutant strain. It was found that the strain had a higher positive mutation rate when the output power was 10 keV and the dose of N+ implantation was 80 × 2.6 × 1013 ions/cm2. Then a high-yield mutant strain D30 was obtained through cid-heating coupling ultrasonic method and lipid yield was 3.10 g/L. Additionally, the surface response method was used to optimize fermentation medium. The three significant factors (glucose, peptone, KH2PO4) were optimized using response surface methodology (RSM), and the optimized parameters of fermentation medium were as follows: glucose 73.40 g/L, peptone 1.06 g/L and KH2PO4 3.56 g/L. Finally the fermentation characteristic of high-yield mutation strain D30 was studied, when fermentation time was 10 days, which lipid yield increased to 7.81 g/L. Fatty acid composition of the lipid was determined by GC, and the most represented fatty acids of mutant D30 were C16:0 (11.4 %), C16:1 (5.66 %), C18:1 (49.3 %), and C18:2 (27.0 %). 相似文献
5.
《Chronobiology international》2013,30(2):263-271
Patients with delayed sleep phase syndrome (DSPS) experiencea chronic mismatch between the usual daily schedule required by the individual'senvironment and their circadian sleep-wake pattern, resulting in major academic,work, and social problems. Although functional abnormalities of the circadianpacemaker system have been reported in patients with DSPS, the etiology ofDSPS has not been fully elucidated. One hypothesis proposed to explain whypatients with DSPS fail to synchronize their 24h sleep-wake cycle to theirenvironment is that they might have reduced sensitivity to environmental timecues, most notably light-dark cycles. Therefore, we compared the sensitivityof melatonin suppression in response to light in patients with DSPS and normalcontrol subjects. Fifteen patients with DSPS and age- and sex-matched healthycontrols were studied. As the melatonin secretion rhythm in patients withDSPS was expected to be delayed compared to the controls, the time of peakmelatonin secretion was determined in each subject in the first session. Inthe second session, each subject was exposed to light with an intensity of1000 lux for 2h beginning 2h prior to his or her peak melatonin secretion.Melatonin was measured by radioimmunoassay in saliva sampled every 30 minutesduring the period of light exposure. Suppression of the melatonin concentrationin saliva was dependent on duration of light exposure. In addition, the suppressiveeffect of light on the melatonin concentration was significantly greater inpatients with DSPS than in control subjects. The results suggest hypersensitivityto nighttime light exposure in patients with this syndrome. Our findings thereforesuggest that evening light restriction is important for preventing patientswith DSPS from developing a sleep phase delay. (ChronobiologyInternational, 18(2), 263–271, 2001) 相似文献
6.
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8.
Marina Monti Alexis Zrimec Alfred Beran Maja Berden Zrimec Luka Drinovec Gorazd Kosi Francesco Tamberlich 《Harmful algae》2005,4(3):643
Delayed luminescence (DL), also termed delayed fluorescence or delayed light emission, is the phenomenon of long-lived light emission by plants and cyanobacteria after being illuminated with light and put into darkness. Culture growth of three Prorocentrum minimum strains was studied with DL measurements. DL decay kinetics was measured from 1–60 s after a pulse of white light. The strains used were from the Adriatic Sea (PmK), from Chesapeake Bay, USA (D5), and from the Baltic Sea (BAL), cultured at salinity of 32, 16, and 8 (practical salinity scale), respectively. The strains differed in cell size and chlorophyll a content (PmK > D5 > BAL), as well as in DL parameters. The DL results were compared to standard measurements of culture density and carbon content (calculated from biovolumes). DL decay curves had a specific peak, which changed with culture growth and showed more similarities between the strains PmK and D5. The DL intensity increased with cell density and carbon content in a two-stage process, corresponding to the lag and exponential phases of growth. DL intensity was best correlated with carbon content irrespective of strain and is proposed as an estimate of biomass and for differentiating between lag and exponential phases of growth. 相似文献
9.
低能离子束在植物种粒和微生物中的穿透深度 总被引:2,自引:0,他引:2
计算了低能离子注入生物体中的穿透深度,考虑生物媒质为匀相多组元系统,求出了平均射程的一般理论公式,将其用于植物种粒和微生物中。以30keV的N 注入水稻种子和100keV的As 注入微生物细胞为例,计算了平均穿透深度,结果与实验资料一致。指出抽真空过程中水分蒸发及离子注入时的热效应和机械效应对植物种子结构的动态影响,可使穿透深度大大加大。 相似文献
10.
氮离子束注入对小麦苗期耐盐性的影响 总被引:3,自引:0,他引:3
采用能量为25keV的不同剂量的N 注入新疆春小麦种胚后,研究盐胁迫对小麦幼苗体内生理生化指标的影响。结果表明,在6×1016N /cm2剂量注入新春11号时,盐胁迫后小麦幼苗的SOD活性、脯氨酸含量、可溶性糖含量、可溶性蛋白含量均增加,幼苗生长良好,说明该剂量处理新春11号有利盐胁迫下小麦幼苗的生长。 相似文献