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991.
大学生应对方式研究   总被引:8,自引:0,他引:8  
介绍了大学生应对方式研究现状.重点阐述了大学生常用的应对方式、影响因素及应对方式对大学生心理健康的影响。  相似文献   
992.
血气分析仪标准溶液定值器是基于Poiseuille定律研制。二氧化碳气体和空气中的氧气在仪器气体混合单元中充分、均匀混合成一定比例的气体,再和标准物质溶液混合,配制出血气分析仪检定用标准溶液。  相似文献   
993.
Recent studies have shown inflammatory markers in affected neural tissues of amyotrophic lateral sclerosis (ALS) patients. We examined immunocytochemically spinal cord tissues of six patients with ALS, two with corticospinal tract degeneration secondary to cerebral infarcts and three control subjects without neuropathologic abnormalities. ALS spinal cords had dense macrophage infiltration (one log greater than control spinal cords) involving the white and gray matter, with heaviest infiltration of lateral and ventral columns and, in one patient, prefrontal gyrus and the occipital lobes of the brain. Macrophages in ALS spinal cord showed strong expression of cyclooxygenase-2 (COX-2) (one log greater than control tissues) and inducible nitric oxide synthase. In the gray matter, macrophages surrounded and appeared to phagocytize neurons (NeuN-positive) that appeared to be dying. Vessels showed damage to the tight junction protein ZO-1 in relation to perivascular CD40 receptor-positive macrophages and CD40 ligand-positive T lymphocytes. ALS spinal cords, but not control cords, were sparsely infiltrated with mast cells. In control cases with corticospinal tract degeneration following hemispheric cerebral infarction, macrophage infiltration of the white matter was COX-2-negative and restricted to lateral and anterior corticospinal tracts. Our data suggest that inflammation in ALS spinal cord and cortex is based on innate immune responses by macrophages and mast cells and adaptive immune responses by T cells.  相似文献   
994.
目的探讨血脂代谢紊乱跟Ⅱ型糖尿病(ⅡDM)患者继发动脉粥样硬化并症的关系。方法采用奥林巴斯Au-640全自动生化分析仪,测定Ⅱ型糖尿病患者和健康对照组的空腹血糖(GLU)、胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白(HDL-C)、载脂蛋白Al(ApoAl)和载脂蛋白B100(ApoBloo),并进行统计、比较并与患者的病情进行对比分祈,并对高血糖、血脂组患者跟踪观察、治疗。结果Ⅱ型糖尿病组同健康对照组比较、Ⅱ型糖尿病患者中有合并症组跟无合并症组、高血糖组跟血糖正常组比较,CHO、TG和ApoBloo的含量均升高(P<0.05),而HDL-C和ApoAI含量降低(P<0.05)。而高血糖、血脂组患者,已经初步出现或在随后的观察中出现了动脉粥样硬化等相关的临床表征,且治疗效果不佳。结论Ⅱ型糖尿病患者血脂的异常,特别是CHO、TG的大幅升高,提示患者在出现动脉硬化性心血管合并症之前,体内已经具备了诱发合并症的生化基础,应早期采取针性治疗和预防措施。  相似文献   
995.
There are a number of problems for evidence‐based practice (EBP) including limited generalizability of efficacy research results, the consequent lack of confidence in the relevance of such research, and the conceptual distance of most practitioners from the research process. The result is that EBP, although sound in principle, often fails to achieve its aim of improving practice. Practice‐based evidence (PBE) provides a complementary bridge for the gap between research and practice to offset some of these problems, promoting collaboration between mental health services and academic institutions. This paper presents the initial results of such a collaboration via three phases: (1) the development of a referential database for primary care counselling services, (2) ‘practitioner‐friendly’ feedback on grouped data to services, and (3) the combination of the two to build an evidence base for work with ethnic minorities—an area in which research trials are not well adapted to provide much evidence. Copyright © 2003 John Wily & Sons, Ltd.  相似文献   
996.
In this paper, the problem of designing H state‐feedback controllers for switched linear discrete‐time systems with polytopic uncertainties is investigated. Two approaches on designing robust and parameter‐dependent H controllers are proposed and the existence conditions of the desired controllers are derived and formulated in terms of a set of linear matrix inequalities. By solving the corresponding convex optimization problem, the desired controllers are obtained, respectively, and different optimal H noise‐attenuation level bounds of corresponding closed‐loop systems are given as well. The designed controllers have their own advantages and disadvantages regarding the conservatism and realization complexity. An illustrative example emerging in networked control systems (NCS) and numerical simulations are presented to show the applicability and effectiveness of the obtained theoretic results. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
997.
Anterior cervical discectomy and fusion (ACDF) may be considered to be the gold standard for treatment of symptomatic degenerative disc disease within the cervical spine. However, fusion of the segment may result in progressive degeneration of the adjacent segments. Therefore, dynamic stabilization procedures have been introduced. Among these, artificial disc replacement by disc prosthesis seems to be promising. However, to be so, segmental motion must be preserved. This, again, is very difficult to judge and has not yet been proven. The aim of the current study was to first analyse the segmental motion following artificial disc replacement using a disc prosthesis. A second aim was to compare both segmental motion as well as clinical result to the current gold standard (ACDF). This is a prospective controlled study. Twenty-five patients with cervical disc herniation were enrolled and assigned to either study group (receiving a disc prosthesis) or control group (receiving ACDF, using a cage with bone graft and an anterior plate.) Radiostereometric analysis was used to quantify intervertebral motion immediately as well as 3, 6, 12 and 24 weeks postoperatively. Further, clinical results were judged using visual analogue scale and neuro-examination. Cervical spine segmental motion decreased over time in the presence of disc prosthesis or ACDF. However, the loss of segmental motion is significantly higher in the ACDF group, when looked at 3, 6, 12 and 24 weeks after surgery. We observed significant pain reduction in neck and arm postoperatively, without significant difference between both groups (P > 0.05). Cervical spine disc prosthesis preserves cervical spine segmental motion within the first 6 months after surgery. The clinical results are the same when compared to the early results following ACDF.  相似文献   
998.
OBJECTIVE: To measure and compare Chinese mandibular genial tubercles measured anatomically and with computed tomography (CT). STUDY DESIGN AND SETTING: Spiral CT scans were taken of 40 adult human skulls; the superior genial spines were measured using anatomic and CT methods. RESULTS: The height and width of the superior genial spines, mandible thickness, and distance from the menton to the inferior and superior margins of the superior genial spines were 5.82 +/- 0.71, 6.98 +/- 1.35, 11.95 +/- 1.59, 11.08 +/- 2.05, and 16.91 +/- 2.30 mm from anatomic measurements and 6.17 +/- 0.71, 7.01 +/- 1.13, 12.19 +/- 1.64, 10.41 +/- 1.55, and 15.73 +/- 2.12 mm using spiral CT, respectively. The anatomic and CT measurements were correlated. CONCLUSION: Spiral CT of the genial tubercles can help locate the osteotomy in genioglossus advancement. SIGNIFICANCE: This study acquired reference data on Chinese genial tubercles demonstrating that CT measurements of the genial tubercles reflect their anatomy, which should allow accurately locate the osteotomy.  相似文献   
999.
Recessive dystrophic epidermolysis bullosa (RDEB) is an uncommon and severe disorder characterised by trauma-induced blisters, intractable skin ulcers, scarring, milia, and nail dystrophy. We report the good result of both surgical release of fingers allowing spontaneous epithelisation without skin grafting and post-operative meticulous skin care without splinting, followed-up for one year.  相似文献   
1000.
OBJECTIVE: To evaluate the findings of computed tomography (CT) and histopathology of the bulla ethmoidalis as objective markers of bone remodeling in chronic rhinosinusitis (CRS). METHODS: Preoperative ostiomeatal unit (OMU) scans and histopathologic findings of the bulla ethmoidalis were performed on 23 patients (39 sides) undergoing endoscopic sinus surgery for CRS. Lund-Mackay scores and Hounsfield units (HU) of the bulla were checked in coronal CT scans. The pathologist graded the severities of the mucosal and bony changes in histopathology. Statistical analysis was performed using Mann-Whitney U test and Spearman correlation coefficient (r). RESULTS: The HU values of the bulla were significantly increased with higher Lund-Mackay scores in OMU CT (r = 0.405, P = 0.01). The bony grades in histopathology were significantly increased with higher mucosal grades (r = 0.821, P = 0.0001). These findings in CT scans and histopathology were well correlated with each other (r > 0.3, P < 0.05). CONCLUSION: HU may be a useful objective marker of bone remodeling in chronic rhinosinusitis.  相似文献   
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