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101.
《Nutrition reviews》1987,45(10):246-248
Increasing dietary 18:2 n-6/18:3 n-3 causes similar relative changes in fatty acid profiles of phosphatidylethanolamine and phosphatidylcholine from rat neural and erythrocyte membranes. 相似文献
102.
Objective To construct new model of experimental abdominal aortic aneurysm (AAA) and detect the AAA outer diameter and the change of induce nitric oxide synthase(iNOS) in the abdominal aor-tic aneurysm in different period,and analysis the correlation between experimental AAA and iNOS.Methods During the operation of the experiment group,the vascular prosthesis of PTFE was implanted to the rabbit abdominal aorta to form an aneurysm,while sham operation was done in the control group.The tissue of ab-dominal aortic aneurysm was harvested in 1 d,7d,14d,and 28d after operation,respectively.The tissue bo-mogenate concentration of iNOS in the abdominal aortic aneurysm were detected by enzyme linked immu-nosorbent assay (ELISA).Results In experimental group,mean concentration of the tissue bomogenate concentration of iNOS in the abdominal aortic aneurysm in 1 d,7 d,14 d,28 d were (22.129 ±2.518)μ/mL,(27.337±5.321) μ/mL,(36.047±4.584)μ/mL,(44.756±1.799)μ/mL,respectively;In control group,that was (12.499±1.807)μ/mL.The concentration of iNOS in experimental group was significantly higher than that of control group (P < 0.01).The difference during the experimental group all had statisti-cal significance (P < 0.05).Conclusion It is possible that iNOS has some biological function during the formation and progression of the abdominal aortic aneurysm. 相似文献
103.
Jocelyn M. Cottrell BS Marjolein C. H. van der Meulen PhD Joseph M. Lane MD Elizabeth R. Myers PhD 《HSS journal》2006,2(1):12-18
The clinical goal of spinal fusion is to reduce motion and the associated pain. Therefore, measuring motion under loading
is critical. The purpose of this study was to validate four-point bending as a means to mechanically evaluate simulated fusions
in dog and rabbit spines. We hypothesized that this method would be more sensitive than manual palpation and would be able
to distinguish unilateral vs bilateral fusion. Spines from four mixed breed dogs and four New Zealand white rabbits were used
to simulate posterolateral fusion with polymethyl methacrylate as the fusion mass. We performed manual palpation and nondestructive
mechanical testing in four-point bending in four planes of motion: flexion, extension, and right and left bending. This testing
protocol was used for each specimen in three fusion modes: intact, unilateral, and bilateral fusion. Under manual palpation,
all intact spines were rated as not fused, and all unilateral and bilateral simulated fusions were rated as fused. In four-point
bending, dog spines were significantly stiffer after unilateral fusion compared with intact in all directions. Additionally,
rabbit spines were stiffer in flexion and left bending after unilateral fusion. All specimens exhibited significant differences
between intact and bilateral fusion except the rabbit in extension. For unilateral vs bilateral fusion, significant differences
were present for right bending in the dog model and for flexion in the rabbit. Unilateral fusion can provide enough stability
to constitute a fused grade by manual palpation but may not provide structural stiffness comparable to bilateral fusion. 相似文献
104.
论高校大学生绿色网络环境的营造 总被引:2,自引:0,他引:2
黄夕彪 《中国医学教育技术》2006,20(5):382-384
介绍了网络文化的迅猛发展对高校大学生的学习方式、生活方式、交往方式产生了巨大冲击,尤其对大学生的身心发展产生了不可忽视的消极影响。指出在高校信息化校园建设中,要加强网络文明的建设,提倡和重视绿色网络,并且从高校大学生的实际出发,努力营造一个健康、文明、有序、安全、具有活力、没有污染的绿色网络环境。 相似文献
105.
Carl A Kirker-Head David C Van Sickle Steve W Ek John C McCool 《Journal of orthopaedic research》2006,24(5):1095-1108
Focal full-thickness cartilage lesions of the human medial femoral condyle (MFC) can cause pain and functional impairment. Affected middle-aged patients respond unpredictably to existing treatments and knee arthroplasty may be required, prompting risk of revision. This study assesses the safety of, and biological and functional response to, a metallic resurfacing implant which may delay or obviate the need for traditional arthroplasty. The anatomic contour of the surgically exposed MFC of six adult goats was digitally mapped and an 11 mm diameter full-thickness osteochondral defect was created. An anchor-based Co-Cr resurfacing implant, matching the mapped articular contour, was implanted. Each goat's contralateral unoperated femorotibial joint was used as a control. Postoperative outcome was assessed by lameness examination, radiography, arthroscopy, synoviocentesis, necropsy, and histology up to 26 (n = 3) or 52 (n = 3) weeks. By postoperative week (POW) 4, goats demonstrated normal range of motion, no joint effusion, and only mild lameness in the operated limb. By POW 26 the animals were sound with only occasional very mild lameness. Arthroscopy at POW 14 revealed moderate synovial inflammation and a chondral membrane extending centrally across the implant surface. Radiographs at POWs 14 to 52 implied implant stability in the operated joints, as well as subchondral bone remodeling and mild exostosis formation in the operated and contralateral unoperated joints of some goats. By POW 26, histology revealed new trabecular bone abutting the implant. At POWs 26 and 52 MFC cartilage was metachromatic and intact in the operated and unoperated femorotibial joints. Proximal tibiae of some operated and unoperated limbs demonstrated limited subchondral bone remodeling and foci of articular cartilage fibrillation and thinning. The chondral membrane crossing the prosthesis possessed a metachromatic matrix containing singular and clustered chondrocytes. Our data imply the safety, biocompatibility, and functionality of the implant. Focal articular damage was documented in the operated joints at POWs 26 and 52, but lesions were much reduced over those previously reported in untreated defects. Expanded animal or preclinical human studies are justified. 相似文献
106.
线栓法制作大鼠局灶性脑缺血再灌注损伤模型的改进 总被引:3,自引:0,他引:3
目的 研究一种稳定、简便的大鼠局灶性脑缺血再灌注损伤模型制作方法。方法 采用健康SD雄性大鼠,线栓法制作局灶性脑缺血再灌注损伤模型.结扎颈总动脉(CCA)及颈外动脉(ECA),不结扎翼腭动脉,用5.0头皮针于CCA结扎的远端刺一小口插入栓塞线造成缺血,拔出线栓形成再灌注。通过神经功能缺损评分、红四氮唑(TTC)染色和病理学检查等方法评价该模型的可靠性。结果动物麻醉后一般只需15min左右即可完成手术,术后大鼠神经功能缺损明显,TTC染色示脑梗塞区苍白,病理学检查显示典型病理表现。结论该方法缺血效果明确可靠,术式简便,手术时间短,不需具备显微手术操作技巧,是一种理想的制作局灶性脑缺血再灌注损伤模型的方法。 相似文献
107.
Howard Litwin 《European journal of ageing》2007,4(2):71-82
The aim of the inquiry was to examine the social network–mortality association within a wider multivariate context that accounts
for the effects of background framing forces and psychobiological pathways. The inquiry was based upon the Berkman et al.
(2000) conceptual model of the determinants of health. Its main purpose was to identify the salient network correlates of 7-year
all cause mortality among Jewish men and women, aged 70 and over, in Israel (n = 1,811). The investigation utilized baseline data from a national household survey of older adults from 1997 that was linked
to records from the National Death Registry, updated through 2004. At the time of the study, 38% of the sample had died. Multivariate
Cox hazard regressions identified two main network-related components as predictors of survival: contact with friends, a social
network interaction variable, and attendance at a synagogue, a social engagement variable. Friendship ties are seen to uniquely
reduce mortality risk because they are based on choice in nature, and reflect a sense of personal control. Synagogue attendance
is seen to promote survival mainly through its function as a source of communal attachment and, perhaps, as a reflection of
spirituality as well. Other possibly network-related correlates of mortality were also noted in the current analysis—the receipt
of instrumental support and the state of childlessness.
The study on which this article is based was made possible by grants from the Israel Ministry of Science and Technology to
the Israel Gerontological Data Center. 相似文献
108.
Profound reductions in cortical acetylcholine levels together with degeneration of cholinergic neurons in the basal forebrain have been reported in patients with Alzheimer's disease. A similar loss of the cholinergic neurons of the basal forebrain and impairment of learning and memory occur in animals injected with a nerve growth factor-diphtheria toxin conjugate, suggesting that this animal model is suitable to analyze cholinergic roles on learning and memory processes, and also the pathogenesis of Alzheimer's disease. In addition, animal models constructed by electrolytic or neurotoxic lesioning of the basal magnocellular nucleus, and models made by transgenetic technology were described. 相似文献
109.
110.