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1.
肉苁蓉多糖对衰老小鼠脂质过氧化的影响   总被引:12,自引:0,他引:12  
目的:研究肉苁蓉多糖(polysacchridesofcistanchedeserticolaY.C.Ma,PCD)对亚急性衰老小鼠的抗 脂质过氧化作用。方法:使用D 半乳糖造成小鼠亚急性衰老模型,观察PCD对亚急性衰老小鼠血液和肝脏组 织中超氧化物岐酶(SOD)、脂质过氧化物(LPO)的含量的影响。结果:灌服肉苁蓉多糖衰老小鼠的血液和肝脏 组织中SOD明显高于模型组(P<0.05);LPO的含量明显低于模型组(P<0.05)。结论:肉苁蓉多糖具有明显 的抗脂质过氧化功能,防止亚急性衰老小鼠的组织脂质过氧化损伤。  相似文献   
2.
In more than 30 years of development of intensive care medicine (ICM), our speciality has acquired moral and ethical standpoints, although not without public pressure and discussions. Special commissions dealing, e.g., with brain death, terminal care, ethics of foregoing life-sustaining treatment in the critically ill, withholding or withdrawing mechanical ventilation, and other issues have meen formed in a number of medical societies. International consensus conferences have helped to clarify some of the issues. With increasing experience, a multitude of ethical problems have arisen in ICM that have to be dealt with, such as the issue of quality of life. What is an unworthy life? Are we allowed to make judgments for our patients? What is cost-effectiveness in ICM? Other restrictions include bed and equipment shortages in the intensive care unit (ICU), the necessity for triage – undisputed in catastrophe medicine – and how one should proceed in managing elective patients? In situations of limited ICU bed availability, sicker patients will be admitted, sparing out patients who are less ill for observation and those with poor quality of life and poor prognosis. For the future, it will likely be necessary to define the patients who should be admitted to an ICU more than those who should not be admitted. An ICU treatment entitlement index would be directly proportional to the probability of successful outcome and the quality of the remaining life, and would be inversely related to costs for achieving success. The ICU outcome with survival, hospital mortality, and follow-up of ICU patients is considered. DNR (do not resuscitate), the dying patient, terminal care, terminal weaning – DNT (do not treat) – active and passive euthanasia, living wills, quality of life, and cost-effectiveness for ICU patients are defined. Their application in the ICU will be discussed and problems pointed out. Outcome predictions using scores (APACHE III, SAPS II, MPM) have been developed based on previous experience, but should only be applied to patient groups and for quality assurance in ICUs. The most frequent and difficult problem in the ICU is the vegetative state, which requires an exact diagnosis. The differential diagnosis from other comatose states such as coma, brain death, and locked-in-syndrome is depicted. The ethics of interrupting life-sustaining treatment in critically ill patients have been worked out by a Task Force on Ethics of the Society of Critical Care Medicine (1990). A consensus was found that the patient may judge to forego therapy; ethically it is then appropriate to withhold or withdraw therapy. According to the consensus, withdrawing an already initiated treatment should not necessarily be regarded as more problematic than a decision not to initiate treatment. In my mind, however, there is a great difference between withdrawing or withholding, e.g., ventilation. A dissentive opinion by some members of the Task Force stated that hydration and nutrition other than high-technology or parenteral nutrition are key components of patient care, and should not be equated with medical intervention. The ethical problems associated with active euthanasia (physician-assisted suicide or death) as practised in the Netherlands are also discussed. In most countries this practice seems unacceptable. From 30 years experience in ICM, there are many more ethical questions and case reports without clear solutions. Care decisions for single patients in unacceptable situations should be made after medical evaluation by the intensivist with the medical team and, if possible, by the patient and/or his or her surrogate. Legislation and solutions cannot be expected for single patients, but ethics committees could be helpful in decision-making.  相似文献   
3.
Defective intestinal tight junction (TJ) barrier is an important pathogenic factor of inflammatory bowel disease. To date, no effective therapies that specifically target the intestinal TJ barrier are available. The purpose of this study was to identify probiotic bacterial species or strains that induce a rapid and sustained enhancement of intestinal TJ barrier and protect against the development of intestinal inflammation by targeting the TJ barrier. After high-throughput screening of >20 Lactobacillus and other probiotic bacterial species or strains, a specific strain of Lactobacillus acidophilus, referred to as LA1, uniquely produced a marked enhancement of the intestinal TJ barrier. LA1 attached to the apical membrane surface of intestinal epithelial cells in a Toll-like receptor (TLR)-2–dependent manner and caused a rapid increase in enterocyte TLR-2 membrane expression and TLR-2/TLR-1 and TLR-2/TLR-6 hetero-complex–dependent enhancement in intestinal TJ barrier function. Oral administration of LA1 caused a rapid enhancement in mouse intestinal TJ barrier, protected against a dextran sodium sulfate (DSS) increase in intestinal permeability, and prevented the DSS-induced colitis in a TLR-2– and intestinal TJ barrier–dependent manner. In conclusion, we report for the first time that a specific strain of LA causes a strain-specific enhancement of intestinal TJ barrier through a novel mechanism that involves the TLR-2 receptor complex and protects against the DSS-induced colitis by targeting the intestinal TJ barrier.

Intestinal epithelial tight junctions (TJs) are the apical-most junctional complexes and act as a functional and structural barrier against the paracellular permeation of harmful luminal antigens, which promote intestinal inflammation.1 The increased intestinal permeability caused by defective intestinal epithelial TJ barrier or a leaky gut is an important pathogenic factor that contributes to the development of intestinal inflammation in inflammatory bowel disease (IBD) and other inflammatory conditions of the gut, including necrotizing enterocolitis and celiac disease.2,3 Clinical studies in patients with IBD have found that a persistent increase in intestinal permeability after clinical remission is predictive of poor clinical outcome and early recurrence of the disease, whereas normalization of intestinal permeability correlates with a sustained long-term clinical remission.4, 5, 6 Accumulating evidence has found that a defective intestinal TJ barrier plays an important role in exacerbation and prolongation of intestinal inflammation in IBD. Currently, no effective therapies that specifically target the tightening of the intestinal TJ barrier are available.Intestinal microbiota play an important role in modulating the immune system and in the pathogenesis of intestinal inflammation.7 Patients with IBD have bacterial dysbiosis in the gut, characterized by a decrease in bacterial diversity and an aberrant increase in some commensal bacteria, which are an important factor in the pathogenesis of intestinal inflammation.8,9 Normal microbial flora of the gastrointestinal tract consists both of bacteria that are known to have beneficial effects (probiotic bacteria) on intestinal homeostasis and bacteria that could potentially have detrimental effects on gut health (pathogenic bacteria).10 The modulation of intestinal microflora affects the physiologic and pathologic states in humans and animals. For example, fecal transplantation from healthy, unaffected individuals to patients with refractory Clostridium difficile colitis is curative in up to 94% of the treated patients, and transfer of stool microbiome from obese mice induces obesity in previous lean mice, whereas transfer of microbiome from lean mice preserves the lean phenotype.11, 12, 13 The beneficial effects of gut microbiota are host and bacterial species-specific.14 Although multiple studies indicate that some commensal bacteria play a beneficial role in gut homeostasis by preserving or promoting the intestinal barrier function, because of conflicting reports, it remains unclear which probiotic species cause a persistent predictable enhancement in the TJ barrier and could be used to treat intestinal inflammation by targeting the TJ barrier. For example, some studies suggest that Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus plantarum, or Lactobacillus rhamnosus cause a modest enhancement in the intestinal epithelial TJ barrier, whereas others have found minimal or no effect of these probiotic species on the intestinal TJ barrier.15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25 The major aim the current study was to perform a high-throughput screening of Lactobacillus and other bacterial species to identify probiotic species that induce a rapid, predictable, and marked increase in the intestinal epithelial TJ barrier and protect against the development of intestinal inflammation by preserving the intestinal TJ barrier.In the studies described herein, most of the probiotic species tested (>20 species or strains) had a modest or minimal effect on intestinal TJ barrier function. L. acidophilus uniquely caused a rapid and marked increase in intestinal TJ barrier function. Further analysis indicated that the effect of L. acidophilus was strain-specific, limited to a specific strain of L. acidophilus, and did not extend to other L. acidophilus strains. The L. acidophilus enhancement of the intestinal TJ barrier was mediated by live bacterial-enterocyte interaction that involved Toll-like receptor (TLR)-2 heterodimeric complexes on the apical membrane surface of intestinal epithelial cells. Our animal studies also found that L. acidophilus causes a marked enhancement in mouse intestinal barrier function and protects against the dextran sodium sulfate (DSS)–induced colitis by preserving and augmenting the mouse intestinal barrier function in a strain-specific manner.  相似文献   
4.
目的:探讨巴马小型猪在脑死亡状态下血清炎症介质的变化及对肝脏损伤的作用。方法:巴马小型猪10只,随机分脑死亡组与对照组,每组5只。用颅内加压法建立脑死亡模型,对照组仅开颅麻醉维持,分别于3、6、12、18和24h取血清测丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)及IL-1β、IL-6和TNF-α水平。结果:(1)炎症介质变化:脑死亡组动物血清IL-1β、IL-6和TNF-α水平均自脑死亡后3h开始升高,并随时间的延长而继续升高;脑死亡后3、6、12、18和24 h脑死亡组明显高于对照组(P<0.05)。(2)肝脏酶学变化:血清ALT、AST水平自脑死亡后12 h开始升高,并随时间的延长而继续升高;脑死亡后12、18和24 h脑死亡组明显高于对照组(P<0.05)。结论:巴马小型猪脑死亡状态下血清炎症介质升高,并随时间的延长而继续升高。脑死亡状态下肝脏功能的损伤可能与这些炎症介质的水平升高有关。  相似文献   
5.
目的:研究苦参碱的镇痛作用部位及机制.方法:采用小鼠醋酸扭体法,观察用后扭体反应数,舔小足潜期及组织NO含量的变化.结果:苦参碱侧脑室注射(icv)0.25,0.5nm/kg,ip或iv3.75,7.5,15,30mg/kg均可显著减少小鼠扭体反应数,并呈量效关系;ip与iv同等剂量的苦参碱,对小扭体反应的抑制欧以iv为强,给药后各时段的ip抗扭体半数有数量(ED50)均大于iv抗扭体ED50,ip苦参碱7.5,30mg/kg可显著降低醋酸致痛小鼠脑组织NO含量,进一步研究发现苦碱延长小鼠舔小足潜伏期的作用可被沦钙所拮抗,而被维拉帕米所增强.结论:苦参碱的镇痛作用部位在中枢,其镇痛作用可能与影响Ca^2 内流和减少NO生成有关.  相似文献   
6.
采用蒸发光散射检测器(ELSD)测定了湖北麦冬中山麦冬皂苷B的含量,结果表明,ELSD是皂苷类化合物较为适宜的检测器。经对不同采收期样品的含量考察,认为湖北麦冬的最佳采收期与传统采收期(清明)相一致。  相似文献   
7.
目的为扩大和提高肉苁蓉Cistanchedeserticola资源的利用效率。方法以肉苁蓉肉质茎的不同组织部位作为外植体,采用正交实验方法,筛选诱导愈伤组织产生的不同培养基和培养条件,并继代培养。应用HPLC方法对愈伤组织培养物中松果菊苷和洋丁香苷(毛蕊花糖苷)的量进行测定。结果肉苁蓉肉质茎的维管组织部分是诱导愈伤组织的最适外植体,鳞片叶次之,髓组织部分诱导效果较差。在暗培养、25~27℃条件下以B5为基本培养基附加6-BA(0.5~2mg/L)与IAA(0.5~1.5mg/L)诱导愈伤组织效果最佳;在半光照(光培养10h/d,暗培养14h/d)条件下,愈伤组织生长正常,最佳继代时间为25~30d。愈伤组织培养物中松果菊苷和洋丁香苷(毛蕊花糖苷)达4.37%。结论筛选出了适宜的肉苁蓉愈伤组织培养方法,且培养物中主要药用有效成分松果菊苷和洋丁香苷(毛蕊花糖苷)的量达到并超过了《中国药典》要求(0.3%)的标准。  相似文献   
8.
笔者总结韩国国立马山结核病医院的见闻,指出韩国医院在护理管理方面的先进模式和经验,以及护理中值得借鉴的地方。  相似文献   
9.
BackgroundCentral catheter infections are of concern in patients on hemodialysis because of the high risk of catheter-related bloodstream infections, sepsis, and death. Adequate nursing is critical for the prevention of such infections. This study aimed to use the PDCA (plan-do-check-act) method to reduce the incidence of central venous catheter infection using management in the maintenance of central venous catheter in patients on hemodialysis, compared with routine care.MethodsThis pilot study recruited patients on hemodialysis via central venous catheterization at the Blood Purification Center of Ruijin Hospital between November 2017 and November 2018. The patients were randomized to the routine and PDCA groups. All participants received routine nursing. The PDCA group received central venous catheter management by PDCA. The incidence of central venous catheterization-related infections, nursing satisfaction, and quality of life were compared between the two groups.ResultsA total of 122 participants were enrolled in each group. The incidence of central catheter-related bloodstream infection, as the primary outcome, was 0.8 and 8.8 cases per 1000 catheter days in the PDCA and routine groups, respectively (P < 0.001). In addition, as the secondary outcomes, the scores of nursing satisfaction (health guidance, nursing technology, and therapeutic effects) score and quality of life (physiological, psychological, social, and environmental status) were better in the PDCA group than in the routine group (all P < 0.01).ConclusionsThis pilot study suggests that the PDCA cycle model can effectively reduce the incidence of central venous catheter-related infections and improve satisfaction and quality of life in patients on hemodialysis.  相似文献   
10.
目的选择肉苁蓉最佳提取工艺参数,研究不同干燥方式对5种苯乙醇苷类成分的影响。方法采用单因素筛选结合Box-Behnken响应面法优化提取工艺。最优条件提取后,利用HPLC法检测不同干燥方式肉苁蓉的松果菊苷、肉苁蓉苷A、毛蕊花糖苷、异毛蕊花糖苷、2′-乙酰基毛蕊花糖苷成分含量并采用单因素方差分析、聚类分析、主成分分析、密切值法分析5种苯乙醇苷类成分含量,选择最佳干燥方式。结果最佳提取工艺:甲醇体积分数55.14%,液料比46.39,提取时间38.50 min。聚类分析、主成分分析、密切值法分析表明,采用冷冻干燥法所得到的肉苁蓉品质最好,80℃烘干次之,40℃烘干最低。结论使用该工艺提取肉苁蓉,其5种苯乙醇苷类成分提取完全、充分。虽然冷冻干燥法炮制肉苁蓉所保留有效成分最高,但从生产角度考虑,采用80℃烘干法炮制能达到成本和功效的平衡。  相似文献   
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