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41.
目的探讨茶多酚对大鼠骨关节软骨氧化损伤的保护作用,以进一步了解茶多酚摄入机体对骨折早期愈合的影响机制。方法选取3~4月龄健康雄性Sprague-Dawley大鼠45只作为观察对象,随机将其分为A、B、C三组,每组15只。各组均制造骨折前茶多酚生物效应,对三组大鼠进行皮下注射,A组剂量为5 mg/(kg·d)茶多酚,B组剂量为10 mg/(kg·d)茶多酚,而C组剂量为0.5 m L/(kg·d)生理盐水;注射3周后,将每只大鼠桡骨中下1/3交界处造成左侧桡骨3 mm完全骨质缺损的骨折模型,不固定;骨折后继续注射茶多酚,制造骨折后茶多酚生物效应;采用HE染色分别观察大鼠在骨折愈合不同时期(造模后3、7、14、21 d)的骨痂厚度及骨痂成熟度。结果 1骨痂厚度:经HE染色观察,造模后3 d,三组间比较差异无统计学意义(P>0.05);造模后7 d,B组明显高于其他两组,差异有统计学意义(P<0.05);造模后14 d,A组与B组明显高于C组,差异有统计学意义(P<0.05);造模后21 d,B组明显高于A组与C组,且A组明显高于C组,各组间差异均有统计学意义(P<0.05)。2A组与B组大鼠术后3 d即可见到骨内外膜开始增厚,术后7 d骨折端肉芽组织形成,术后14 d骨折端肉芽组织开始重新生长,术后21 d骨折端纤维性骨痂与纤维母细胞有明显减少;C组术后3、7 d骨内外膜也有所增厚,但是与术前相比差异不明显,术后14、21 d骨痂中纤维细胞、毛细血管密度及纤维性结缔组织有明显增加,出现新生血管,但是成骨细胞的增殖数量与A、B组相比明显偏低,而且骨痂的成熟度也相对较低,内外骨痂改造塑形期出现较晚。结论茶多酚对骨关节软骨氧化损伤具有明显的保护作用,其可以通过促进骨痂增殖分化,增加骨痂含量,加快骨痂的成熟,从而提高骨折的愈合速度。 相似文献
42.
目的:分析探讨地塞米松和甘露醇合用对急性重症脑血管病脑保护作用的疗效。方法整群选取该院2011年8月-2013年8月收治的急性重症脑血管病患者88例,随机分为对照组和观察组,对照组患者采用甘露醇治疗,观察组患者采用地塞米松联合甘露醇治疗。比较两组患者的颅内压(ICP),并发症和格拉斯哥昏迷(GCS)评分。结果观察组患者不同时间段ICP恢复正常例数所占比率与对照组比较差异有统计学意义,P<0.05;两组患者治疗期间并发症发生率比较差异无统计学意义,P>0.05;治疗后第3个月,观察组患者的GCS评分明显优于对照组,P<0.05,具有统计学意义。结论地塞米松与甘露醇合用治疗急性重症脑血管疾病,患者ICP恢复速度快,患者预后情况良好,且不会增加治疗期间的并发症,能够有效降低颅内压、保护脑细胞、减轻脑水肿,值得临床大力推广。 相似文献
43.
Blueprint for schistosomiasis vaccine development 总被引:28,自引:0,他引:28
A number of different schistosome antigens are capable of partially protecting experimental animals from challenge infection. More than 100 such antigens have been identified, about 15% of which are strongly protective and deemed promising though they do not reach the level close to sterile immunity seen after vaccination with irradiated cercariae. Studies of human correlate reactions, i.e. serological reactions and cytokine responses to schistosomiasis antigens, in individuals living in areas endemic for schistosomiasis have shown associations between certain antigen-specific immune responses and lack of re-infection over time. This approach was applied in Brazil and Egypt where it was possible to epidemiologically follow cohorts of individuals in endemic areas for extended periods of time correlating infection status with immune responses against a panel of well-researched, highly purified vaccine candidates. The immune correlates found were unique to each antigen and could be either positive or negative, i.e. associated with resistance or with susceptibility to re-infection. However, few antigens were clear-cut in this respect, i.e. the majority of them induced ambiguous responses. For example, a single antigen might have a significant positive correlation when antigen-driven interferon (INF)-gamma production is measured but also show a significant negative correlation with respect to the IgG1 titre induced. These observations suggest that there are desirable, antigen-specific immune responses that would be valuable in a vaccine but they also indicate that there are responses that must be avoided. The insights gained should be useful not only for antigen selection but also for vaccine formulation prior to Phase I/II trials in humans. It would be of great value if similar independent, long-term human correlate studies could also be undertaken in areas endemic for Schistosoma japonicum. 相似文献
44.
Participation of Phosphoinositides in Gastric Mucosal Protection by Colloidal Bismuth Subcitrate against Ethanol-Induced Injury 总被引:1,自引:0,他引:1
Bronislaw L. Slomiany Xiaoying Wang Danuta Palecz Kazuichi Okazaki Amalia Slomiany 《Alcoholism, clinical and experimental research》1990,14(4):580-583
The mechanism of gastric mucosal protection by an antiulcer agent, colloidal bismuth subcitrate (CBS), against ethanol-induced injury was investigated using in vivo and in vitro systems. The experiments in vivo were conducted with groups of rats with and without indomethacin pretreatment, and the animals received either a dose of CBS (100 mg/kg) or a vehicle (saline), followed 30 min later by ethanol. In the in vitro studies, gastric mucosa segments were cultured in the presence of CBS, ethanol, or both. The results of in vivo experiments revealed that in the absence of CBS, ethanol caused extensive gastric hemorrhagic lesions which were significantly reduced following CBS pretreatment and this effect of CBS was not prevented by indomethacin. The data obtained with gastric mucosal culture established that in comparison to the controls, ethanol caused a 27% decrease in mucin synthesis, while mucin synthesis in the presence of CBS increased by 48%. The increase in mucin synthesis evoked by CBS was accompanied by the enhanced metabolism of mucosal phosphoinositides, as reflected by a decrease in PI (15%) and PIP2 (30%), and an increase in IP1 (26%) and IP3 (67%). In contrast, ethanol, which exhibited detrimental effect on mucin synthesis, caused a decrease in PIP (35%), IP2 (47%) and IP3 (38%), and an increase in PIP2 (80%), and IP1 (51%). However, when the mucosal culture was carried out in the presence of both CBS and ethanol, the detrimental changes evoked by ethanol on mucin synthesis were prevented, and the phosphoinositide and inositide phosphate distribution patterns were quite similar to those in the mucosa cultured in the presence of CBS only.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
45.
Chris Ifediora 《The Australasian medical journal》2015,8(7):239-246
Background
Aggression against doctors involved in after-hours house calls (AHHC) is widely perceived to be high. It is, however, unclear how doctors who perform this service manage the risk of aggressive patients during home visits.Aims
The aim of this paper is to explore if and how doctors manage the risk of violence against them during AHHC.Methods
A survey was designed and administered to all 300 Australian-based doctors engaged in AHHC under the National Home Doctor Service (NHDS). The survey was conducted from September 2014 to November 2014.Results
There were 172 responses (57.3 per cent). Only 43 per cent of respondents adopted personal protective measures. The remaining 57 per cent had none; of those 6 per cent had never considered protective measures, and 31.8 per cent were aware of the risk of violence, but were unsure of what to do. Measures adopted include the use of chaperones/security personnel (34.1 per cent), dependence on surgery policies (31.2 per cent), de-escalation techniques (15.2 per cent), panic buttons (7.2 per cent), personal alarms (6.1 per cent), and others (6.5 per cent). Females were more likely to adopt personal protective measures than males (OR 4.94; p<0.01; CI 1.70–14.34), and Australian-trained doctors were less likely to do so relative to overseas-trained doctors (OR 0.35; p=0.04; CI 0.12–0.99).Conclusion
Just over half of the doctors involved in AHHC took no precautions against aggressive attacks while on duty, and nearly one-third relied on the policies of their employing surgeries. 相似文献46.
《Vaccine》2015,33(48):6800-6808
A replication-deficient chimpanzee adenovirus expressing Ag85A (ChAdOx1.85A) was assessed, both alone and in combination with modified vaccinia Ankara also expressing Ag85A (MVA85A), for its immunogenicity and protective efficacy against a Mycobacterium tuberculosis (M.tb) challenge in mice. Naïve and BCG-primed mice were vaccinated or boosted with ChAdOx1.85A and MVA85A in different combinations. Although intranasally administered ChAdOx1.85A induced strong immune responses in the lungs, it failed to consistently protect against aerosol M.tb challenge. In contrast, ChAdOx1.85A followed by MVA85A administered either mucosally or systemically, induced strong immune responses and was able to improve the protective efficacy of BCG. This vaccination regime has consistently shown superior protection over BCG alone and should be evaluated further. 相似文献
47.
以湖南省永州市传统村落为研究对象,通过实地走访调查,详细了解永州市传统村落文化的知识产权保护现状及存在的问题及其原因,探讨了传统村落文化知识产权的保护模式。 相似文献
48.
Moges S. Ido Michael R. Frankel Ike S. Okosun Richard B. Rothenberg 《The American journal of emergency medicine》2018,36(2):262-265
Introduction
Intravenous alteplase reduces disability and improves functionality among acute ischemic stroke patients. Two decades after its approval, only a small fraction of patients get the treatment, and demonstrating its impact on mortality may make a strong case for its wider use. This study assessed the impact of thrombolytic treatment by alteplase on 1-year mortality and readmission among acute ischemic stroke patients.Method
The 2008–2013 Georgia Coverdell Acute Stroke Registry data were linked with the 2008–2013 hospital discharge and the 2008–2014 death data in Georgia. Multiple imputation was applied; a propensity score measuring the probability of receiving intravenous alteplase was calculated and used for matching. A conditional logistic regression was applied to compare 1-year mortality and readmission among propensity score matched pairs.Results
Overall, 20.3% of 9620 acute ischemic stroke patients died and 22.4% were readmitted in one year. The multivariable regression result showed that patients who did not receive IV alteplase had a 1.49 (95%CI: 1.09–2.04; p-value = 0.01) times higher odds of dying at one year than those who were treated with the thrombolytic agent. Among patients discharged home, no statistically significant difference was documented in the odds of being readmitted at least once within 365 days post-stroke discharge.Discussion and conclusion
After accounting for patient differences and missing value, intravenous alteplase is associated with reduction in long-term mortality. The results of this study suggest that patients who are identified as eligible for intravenous alteplase need to be offered the treatment. 相似文献49.
Anat Galor D. Diane Zheng Kristopher L. Arheart Byron L. Lam Kathryn E. McCollister Manuel A. Ocasio 《Ophthalmic epidemiology》2015,22(1):28-33
ABSTRACTObjective: To evaluate the association between sociodemographic factors and eye care expenditure and to assess the burden of ocular expenditure compared to total health care expenditure.Methods: A retrospective analysis of ocular expenditure in participants of the 2007 Medical Expenditure Panel Survey. Data from 20,620 unique participants aged ≥18 years were evaluated for eye care expenditure by demographic characteristics.Results: A total of 22% of the studied population had eye care expenditures in 2007. Demographic factors significantly associated with higher probability of having eye care expenditures included older age (65+ years 35%, 45–64 years 23%, <45 years 17%), female sex (female 26%, male 19%), higher educational attainment (greater than high school education 25%, less than high school education 17%), having insurance (private 24%, uninsured 13%), and visual impairment (mild 31%, none 22%). Older age, female sex, higher educational attainment, having insurance, and presence of visual impairment were also significantly associated with higher mean eye care expenditure. In those with eye care expenditure, the mean ratio between eye care and total medical expenditure was 24%, with uninsured patients spending 42% of their medical care expenditure on eye care.Conclusions: Demographic factors are associated with both the probability of having ocular expenditure and the amount of expenditure. Of all factors examined, insurance status has the most potential for modification. Policy makers should consider these numbers when devising the terms by which eye care coverage will be provided under the Patient Protection and Affordable Care Act. 相似文献
50.
《Journal of the American College of Radiology》2015,12(3):228-234
The current initiative to reform health care from both a quality and a cost perspective has already had a profound impact on the radiology enterprise. We have seen a decrease in the utilization of imaging studies, a reduction in reimbursement, a declining payer mix, shrinking incomes, a proliferation of performance indices, creation of radiology mega-groups, growth of national radiology companies, and increasing turf incursions. Our cheese is clearly on the move, and we must take action to reengineer the radiology enterprise. In keeping with general health care reform, we must be patient-centric, data driven, and outcome based. We must create a radiology enterprise that adheres to the value equation of providing the highest quality health care, for the lowest possible cost, for all citizens. 相似文献