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41.
目的比较超声、Er,Cr:YSGG激光及Er:YAG激光辅助1%次氯酸钠(NaOCl)溶液冲洗对人离体牙根管表面粪肠球菌生物膜及根尖区不同深度牙本质小管内粪肠球菌的杀灭效果。
方法单直根管下颌前磨牙42颗,建立粪肠球菌生物膜感染的根管模型,采用随机字表法随机抽取2颗确定建成粪肠球菌生物膜感染根管模型,剩余40颗牙采用随机数字表法按随机对照原则分为5组,每组8颗。A组:5.25% NaOCl联合17%乙二胺四乙酸(EDTA)注射器冲洗;B组:0.9%氯化钠溶液注射器冲洗;C组:1% NaOCl溶液超声荡洗;D组:1% NaOCl溶液Er:YAG激光活化冲洗;E组:1% NaOCl溶液Er,Cr:YSGG激光活化冲洗。按分组进行处理后取样菌落计数,计算灭菌率。使用SPSS 17.0统计软件对实验数据进行方差齐性及正态性检验比较各组间和组内的灭菌率。
结果(1)组间比较:对根管壁表面,各组冲洗方法灭菌率比较,B组(5.74%)相似文献
42.
Asthma is a phenotypically heterogeneous disorder of multifactorial origins that affects 300 million people suffering from asthma and more than 250,000 asthma-related deaths each year. Although treatment for asthma has improved, its prevalence continues to increase, particularly in low and middle income countries, or in some ethnic groups in which prevalence was previously low. Observed spatio-temporal variations in the increased prevalence of asthma depend on exposure to environmental factors. Recently, several arguments are also in favor of the involvement of host susceptibility and stress in the observed increase of asthma prevalence. Further?investigations are warranted to better understand mechanisms underlying asthma increase or stagnation. 相似文献
43.
《The journal of spinal cord medicine》2013,36(6):792-804
AbstractIntroductionIn order to develop optimal treatments to promote recovery from complete spinal cord injury (SCI), we examined the combination of: (1) a cellular graft of neural and glial restricted precursor (NRP/GRP) cells, (2) passive exercise, and (3) chronic quipazine treatment on behavioral outcomes and compared them with the individual treatment elements. NRP/GRP cells were transplanted at the time of spinalization.MethodsDaily passive exercise began 1 week after injury to give sufficient time for the animals to recover. Chronic quipazine administration began 2 weeks after spinalization to allow for sufficient receptor upregulation permitting the expression of its behavioral effects. Behavioral measures consisted of the Basso, Beattie, and Bresnahan (BBB) locomotor score and percent of weight-supported steps and hops on a treadmill.ResultsRats displayed an increased response to quipazine (BBB ≥ 9) beginning at 8 weeks post-injury in all the animals that received the combination therapy. This increase in BBB score was persistent through the end of the study (12 weeks post-injury).ConclusionUnlike the individual treatment groups which never achieved weight support, the combination therapy animals were able to perform uncoordinated weight-supported stepping without a body weight support system while on a moving treadmill (6.5 m per minute) and were capable of supporting their own weight in stance during open field locomotion testing. No regeneration of descending serotonergic projections into and through the lesion cavity was observed. Furthermore, these results are a testament to the capacity of the lumbar spinal cord, when properly stimulated, to sustain functioning locomotor circuitry following complete SCI. 相似文献
44.
Mariska Bot Jacqueline M. Vink Gonneke Willemsen Johannes H. Smit Jacoline Neuteboom Cornelis Kluft Dorret I. Boomsma Brenda W.J.H. Penninx 《Journal of psychosomatic research》2013
Objective
Previous population-based studies suggest that exposure to secondhand smoke (SHS) is related to increased depressive symptoms and poor mental health among non-smokers. We examined whether these associations could be replicated in two independent Dutch samples.Methods
Non-smoking adults were selected from two studies: 1) the Netherlands Study of Depression and Anxiety (NESDA), comprising individuals with current and remitted depressive and/or anxiety disorders, and healthy controls and 2) the Netherlands Twin Register (NTR), comprising twin-family studies on health-related behaviors. In both studies, SHS exposure was assessed with plasma cotinine levels (1–14 ng/ml vs. < 1 ng/ml). In NESDA, outcomes were current depressive and/or anxiety disorders, and depression and anxiety symptom severity scores. In NTR, the Adult Self Report derived DSM-subscales for depressive and anxiety problems, and anxious depressive scores were analyzed.Results
In NESDA non-smokers (n = 1757), increased plasma cotinine level (≥ 1 ng/ml) was not related to current depressive and/or anxiety disorders [odds ratio (OR) 0.96, P = .77], nor to depression or anxiety severity indicators. Similarly, in NTR non-smokers (n = 1088) cotinine levels ≥ 1 ng/ml were not associated with the DSM-subscale for depressive problems [unstandardized regression coefficient (B) 0.04, P = .88], nor to other depression and anxiety measures.Conclusions
In non-smoking adults from patient and population samples, we found no evidence that plasma cotinine levels were related to either depressive and/or anxiety disorders, or to depressive and anxiety symptoms. This suggests that SHS exposure is not related to depression and anxiety in non-smoking adults. 相似文献45.
Mickael Dinomais Eva Chinier Gregoire Lignon Isabelle Richard Aram Ter Minassian Sylvie Nguyen The Tich 《Research in developmental disabilities》2013,34(10):3487-3496
In patients with cerebral palsy (CP), neuroimaging studies have demonstrated that passive movement and action–observation tasks have in common to share neuronal activation in all or part of areas involved in motor system. Action observation with simultaneous congruent passive movements may have additional effects in the recruitment of brain motor areas. The aim of this functional magnetic resonance imaging (fMRI) study was to examine brain activation in patients with unilateral CP during passive movement with and without simultaneous observation of simple hand movement. Eighteen patients with unilateral CP (fourteen male, mean age 14 years and 2 months) participated in the study. Using fMRI block design, brain activation following passive simple opening–closing hand movement of either the paretic or nonparetic hand with and without simultaneous observation of a similar movement performed by either the left or right hand of an actor was compared. Passive movement of the paretic hand performed simultaneously to the observation of congruent movement activated more “higher motor areas” including contralesional pre-supplementary motor area, superior frontal gyrus (extending to premotor cortex), and superior and inferior parietal regions than nonvideo-guided passive movement of the paretic hand. Passive movement of the paretic hand recruited more ipsilesional sensorimotor areas compared to passive movement of the nonparetic hand. Our study showed that the combination of observation of congruent hand movement simultaneously to passive movement of the paretic hand recruits more motor areas, giving neuronal substrate to propose video-guided passive movement of paretic hand in CP rehabilitation. 相似文献
46.
李鼎 《航空航天医学杂志》2016,(5):546-547
目的:探讨颈动脉超声在被动吸烟人群中动脉硬化程度方面的应用价值。方法选择健康状态,无吸烟史人群100例,被动吸烟人群100例,长期吸烟人群100例分为对照组,被动吸烟组,吸烟组,应用高频超声分别观测各组颈动脉动脉硬化情况,有斑块者测量斑块大小及数量,有狭窄者测量狭窄程度。结果被动吸烟组动脉硬化程度较正常组明显增高,颈动脉内中膜厚度随被动吸烟时间增加而增厚。结论长期被动吸烟者可增加脑卒中的发病危险,因为人群的高暴露率,即使对单一个体影响很小,但也是一个非常重要的危险因素。 相似文献
47.
目的:探讨被动抬腿试验(PLR)和容量负荷试验(VE)评估ICU感染性休克患者容量反应性的意义。方法选取2010年5月至2015年5月我院ICU收治的感染性休克患者100例作为研究对象。所有患者依次行PLR和VE。记录基线、PLR和VE后心率(HR)、平均动脉压(MAP)、中心静脉压(CVP)、每搏量(SV)、胸腔内血容量(ITBV)和全心舒张末期容量(GEDV)等数据。对比分析有容量反应性患者和无容量反应性患者血流动力学变化。采用ROC曲线分析PLR和VE预测感染性休克患者容量性反应的价值。结果100例参与试验的患者中有容量反应性48例,无容量反应性52例。有容量反应性组患者在PLR和VE后,CVP和SV均较基线明显升高,差异均有统计学意义(P<0.05);组内比较,两组患者HR、MAP、CVP、SV、ITBV和GEDV在PLR和VE后的变化比较差异均无统计学意义(P>0.05)。Pearson相关分析显示,PLR后△SV与VE后△SV存在显著正相关性(r=0.460,P=0.001);PLR后△SV曲线面积为0.880(95%CI:0.786~0.973),VE后△SV曲线面积为0.859(95%CI:0.760~0.958),二者比较差异无统计学意义(P>0.05);在PLR期间,当△SV为14.5%时诊断容量反应性的灵敏度为77.3%,特异度为85.7%;在VE期间,当△SV为13.1%时诊断容量反应性的灵敏度为72.7%,特异度为75.0%。结论 PLR和VE对感染性休克患者容量反应性的评估价值高于CVP、ITBV、GEDV等指标,结合△SV则拥有较高的灵敏度和特异性。 相似文献
48.
Vibration applied to the Achilles tendon is well known to induce in freely standing subjects a backward body displacement and in restrained subjects an illusory forward body tilt. The purpose of the present experiment was to evaluate the effect of Achilles tendon vibration (90Hz) on postural orientation in subjects free of equilibrium constraints. Subjects (n=12) were strapped on a backboard that could be rotated in the antero-posterior direction with the axis of rotation at the level of the ankles. They stood on a rigid horizontal floor with the soles of their feet parallel to the ground. They were initially positioned 7 degrees backward or forward or vertical and were required to adjust their body (the backboard) to the vertical orientation via a joystick. Firstly, results showed that in response to Achilles tendon vibration, subjects adjusted their body backward compared to the condition without vibration. This backward body adjustment likely cancel the appearance of an illusory forward body tilt. It was also observed that the vibratory stimulus applied to the Achilles tendon elicited in restrained standing subjects an increased EMG activity in both the gastrocnemius lateralis and the soleus muscles. Secondly, this vibration effect was more pronounced when passive displacement during the adjustment phase was congruent with the simulated elongation of calf muscles. These results indicated that the perception of body orientation is coherent with the postural response classically observed in freely standing subjects although the relationship between these two responses remains to be elucidated. 相似文献
49.
Di Gregorio R Parenti-Castelli V O'Connor JJ Leardini A 《Medical & biological engineering & computing》2007,45(3):305-313
The paper presents a theoretical model of the ankle joint, i.e. tibio-talar articulation, which shows how the articular surfaces
and the ligaments, acting together as a mechanism, can control the passive kinematics of the joint. The authors had previously
shown that, in virtually unloaded conditions, the ankle behaves as a single degree-of-freedom system, and that two ligament
fibres remain nearly isometric throughout the flexion arc. Two different equivalent spatial parallel mechanisms together with
corresponding kinematic models were formulated. These assumed isometricity of fibres within the calcaneal-fibular and tibio-calcaneal
ligaments and rigidity of the articulating surfaces, taken as three sphere-plane contacts in one model, and as a single spherical
pair in the other. Geometry parameters for the models were obtained from three specimens. Motion predictions compare quite
well with the measured motion of the specimens. The differences are accounted for by the simplifications adopted to represent
the complex anatomical structures, and might be reduced by future more realistic representations of the natural articular
surfaces. 相似文献
50.
The role of both inertial and stable cavitation was investigated during in vitro ultrasound-accelerated fibrinolysis by recombinant tissue plasminogen activator (rt-PA) in the presence and absence of Optison. A unique treatment configuration applied ultrasound, rt-PA and Optison to the interior of a plasma clot. Lysis efficacy was measured as clot weight reduction. Cavitational mechanisms were investigated by monitoring subharmonic and broadband noise. In the absence of Optison, 1.7 MHz pulsed ultrasound with 1.5 MPa peak-negative pressure applied for 30 min resulted in 45 +/- 19% lysis enhancement relative to rt-PA alone. Cavitation was not detected, indicating a role of noncavitational effects of ultrasound. The addition of Optison increased lysis enhancement to 88 +/- 25%. Inertial cavitation was present only at the start of the exposure, while low-amplitude subharmonic emissions persisted throughout. Additional protocols suggested a possible correlation between the increased lysis in the presence of Optison and the subharmonic emission, indicating a potentially important role of stable rather than inertial cavitation in microbubble-enhanced ultrasound-accelerated rt-PA-mediated thrombolysis. 相似文献