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61.
Introduction and importanceThe aim of this article is to report the long-term outcome of full mouth rehabilitation with single piece, smooth surface implants following immediate loading protocol on a patient suffering with RA and severe unilateral condylar resorption.Case presentationHere, we present a challenging case of a patient suffering from Rheumatoid Arthritis who was stabilized and completed successfully with a 4 year follow-up period. Prosthetic management optimized the inter-occlusal relationship to maintain both function and esthetic integrity. Single piece implants are designed to engage and take support from the cortical bone low in metabolic activities thus promoting the force transmission through apical threads that are engaged in the cortical bone.DiscussionRheumatoid Arthritis [RA] is an auto-immune inflammatory condition in which the inflamed and hypertrophic synovial membrane grows into the articulation surfaces. The Temporomandibular Joints [TM] are frequently involved in rheumatoid arthritis. According to the literature on RA, due to frequent periodontitis, decreased salivary secretion, medication, as well as decrease in bone regenerative potential, RA is often considered as a relative contraindication in the use of implants. Atrophic jaws and cases with comorbidities like osteoporosis, diabetes, rheumatoid arthritis, periodontally infected cases are restored with high success by single piece smooth surface.ConclusionTo the best of our knowledge, this may be the first case of immediate functional loading by bi-cortical single piece implants. 相似文献
62.
Single channel activity associated with the calcium dependent outward current inHelix pomatia 总被引:1,自引:0,他引:1
A recently improved version of the extracellular patch clamp technique (9, 13) was used to record currents from microscopic membrane areas of Helix neurons with predominant Ca2+ dependent outward currents. Current fluctuations in the patches consisted mainly of frequently interrupted, one-sided steps indicating discrete open-closed state changes of single channels with an ohmic conductance of approximately 19 pS. Frequency of occurrence of the elementary events compares with amplitudes of macroscopic currents during depolarizing voltage steps of varied amplitude. Average delays in appearance of the events vary in line with delayed time courses of the cell's outward current. 相似文献
63.
单片微机化微弱发光测量仪及其在肿瘤研究中的初步应用 总被引:2,自引:0,他引:2
单片微机化微弱发光测量仪由中科院生物物理所和北京科龙生物医学技术开发公司研制成功。该仪器适用于肿瘤研究中生物医学样品的微弱发光的测量。测量样品的重复性优于0.8%,稳定性优于0.5%,线性相关系数达0.9997,不仅可以进行样品的发光强度测量,还可以进行动力学曲线的测量以及样品发射光谱的测量。光谱在400nm-750nm范围内。测量方式可选择手动、半自动和自动计时三种。测量结果表明,荷瘤裸鼠血液微 相似文献
64.
F. Duboeuf D. Uebelhart G. Boivin C. Edouard P. D. Delmas P. J. Meunier 《Clinical rheumatology》1990,9(3):367-373
Summary Bone mineral density (BMD) measured by single photon absorptiometry (SPA) with a Moolsgard 1100® device on the distal and proximal part of the radius was compared with histomorphometric parameters measured on iliac crest biopsies in 37 patients suffering from various bone disorders. In the whole population, a good correlation was observed between the cancellous bone volume (Cn-BV/TV) measured on iliac crest biopsies and BMD from both the proximal part of the radius (r=0.76, p < 0.001) and the distal part of the radius (r=0.73, p < 0.001). Significant, although weaker correlations, were also found between the cortical width and the BMD from the distal part (r=0.37, p < 0.001) and the proximal part (r=0.44, p < 0.001) of the radius. In the 14 untreated osteoporotic patients, only a significant Spearman correlation was observed between the iliac Cn-BV/TV and the proximal radial BMD (r=0.69, p < 0.05). It is thus not clear, whether radial proximal BMD correctly indicates cortical bone density in osteoporotic patients or not. The large internal variability of each of the two investigated methods and the small group of osteoporotic patients might explain the lack of correlation between the two methods in this group. 相似文献
65.
目的:研究本地区临床分离结核杆菌rpoB基因突变与利福平(RFP)耐药性的关系。方法:对36株RFP敏感株和44株RFP耐药株rpoB基因的328bp的PCR扩增产物进行单链构象多态性(Single-strand comformationpolymorphism,SSCP)分析。结果:36株RFP敏感株的SSCP带谱均与参考株H37Rv相同,44株RFP耐药株中,25株高度RFP耐药株和11株低度RFP耐药株的SSCP带谱与H37Rv带谱有差异;另8株低度RFP耐药株的SSCP带谱与H37Rv带谱相同。结论:SSCP分析可检测出rpoB基因突变,该基因突变与本地区临床分离结核杆菌对RFP耐药有关。 相似文献
66.
4-Phenyl-1-(4-phenylbutyl)piperidine(4-PPBP) is a very potent ligand for σ (Sigma) receptors. The present study was undertaken to evaluate [3H]4-PPBPas a radioligand for in vivo labeling of cerebral σ receptors. After intravenous administration of [3H]4-PPBP to mice, there is high uptake of radioactivity in the brain. The regional distribution of radioactivity in the brain 2 h after intravenous injection of [3H]4-PPBP parallels the in vitro binding of the radioligand in rat brain (pons/medulla > cerebellum ≥ prefrontal cortex ≥ parietal cortex > hypothalamus > olfactory tubercle ≥ thalamus > hippocampus > striatum). Pretreatment with haloperidol (2 mg/kg) significantly decreases the radioactivity measured in the brain 30–120 min after injection of [3H]4-PPBP. Pretreatment with unlabeled 4-PPBP or ifenprodil also significantly decreases radioactivity in the brain 2 h after injection of [3H]4-PPBP, in a dosedependent manner. The in vivo binding of [3H]4-PPBP in the brain also is significantly inhibited by SL 82.0715, BMY 14802, 1,3-di-o-tolylguanidine (DTG), and (+)-enantiomers of pentazocine, SKF 10,047, and 3-PPP, but not by the corresponding (?)-enantiomers, consistent with stereoselectivity of inhibition obtained in in vitro binding studies. In contrast, pretreatment with dizocilpine and spiperone does not inhibit in vivo binding of [3H]4-PPBP. The results indicate that [3H]4-PPBP would be a suitable radioligand for in vivo labeling of σ receptors in brain. © 1995 Wiley-Liss, Inc. 1 This article is a US Government work and, as such, is in the public domain in the United States of America . 相似文献
67.
Kenya Murase Shuji Tanada Takeshi Inoue Yoshifumi Sugawara Ken Hamamoto 《European journal of nuclear medicine and molecular imaging》1993,20(1):32-38
Attenuation coefficient maps (-maps) are a useful way to compensate for non-uniform attenuation when performing single photon emission tomography (SPET). A new method was developed to record single photon transmission data and a-map for the brain was produced using a four-head SPET scanner. Transmission data were acquired by a gamma camera opposite to a flood radioactive source attached to one of four gamma cameras in the four-head SPET scanner. Attenuation correction was performed using the iterative expectation maximization algorithm and the-map. Phantom studies demonstrated that this method could reconstruct the distribution of radioactivity more accurately than conventional methods, even for a severely non-uniform-map, and could improve the quality of SPET images. Clinical application to technetium-99m hexamethylpropylene amine oxime (HMPAO) brain SPET also demonstrated the usefulness of this method. Thus, this method appears to be promising for improvement in the image quality and quantitative accuracy of brain SPET.This work was presented in part at the World Congress on Medical Physics and Biomedical Engineering, 7–12 July 1991, Kyoto, Japan 相似文献
68.
Jose Sänchez-Chapula 《Naunyn-Schmiedeberg's archives of pharmacology》1992,345(3):342-348
Summary The effects of the beta-adrenoceptor antagonist metoprolol on action potentials and membrane currents were studied in single guinea-pig ventricular myocytes. The experiments were carried out using the nystatin-method of whole-cell technique. This method was used in order to prevent the run-down of the calcium current. Metoprolol at concentrations of 10–100 mol/l shortened action potential in a dose-dependent way. The drug only decreased resting membrane potential at a concentration of 100 mol/1 in two out of five cells. Under voltage-clamp conditions, metoprolol blocked the high threshold calcium current at concentrations of 30 and 100 mol/l to 82 ± 4% and 73 ± 5% from control, respectively. The drug decreased the inward rectifying potassium current in a concentration-dependent manner. This effect was evident for inward current at voltages negative to the apparent reversal potential and for outward current at voltages between –30 and –80 mV. This blocking effect on the inward rectifying potassium current can explain the effect on resting membrane potential. At voltages positive to –30 mV metoprolol increased a time-independent outward current. This metoprolol-enhanced outward current was blocked by barium and cesium. This result suggests that the metoprolol-enhanced current is carried by potassium. The current component enhanced by metoprolol was not sensitive to glibenclamide and tetraethylammonium applied externally, which suggests that the adenosine triphosphate-sensitive channel is not the target of metoprolol. The activation of this time-independent outward current by metoprolol and the blocking effects on the calcium current seem to explain the shortening in action potential induced by the drug.
Send offprint requests to J. Sánchez-Chapula at the above address 相似文献
69.
W. Jiang C. E. Chapman Y. Lamarre 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1991,84(2):342-354
Summary The present experiments were designed to investigate the neuronal mechanisms, at the level of the primary somatosensory cortex, which underlie the observation that somatosensory cortical potentials evoked by air puff stimuli directed at the forearm are decreased, in a nonspecific and widespread manner, during voluntary movements about the elbow. Unitary discharge was recorded from 131 cells receiving cutaneous input from the hairy skin of the forearm or hand (areas 3b and 1) of two monkeys trained to perform rapid movements of the contralateral arm (elbow flexion or extension). Evoked unitary responses to air puff stimuli applied to the centre of the cell's receptive field, at various delays before and after the onset of movement, were recorded. Movement produced a significant decrease in the short latency excitatory response to the air puff in 89% of the cells (117/131); the remaining 11% were not modulated by movement. This movement-related gating of cutaneous inputs occurred regardless of the response pattern of the cells to movement alone, being observed in 91% of the cells with no movement-related discharge, and 89% of those with movement-related discharge. The air puff responses of cells with inputs from the forearm and the dorsum of the hand were all similarly modulated by movement and the modulation was clearly present prior to the onset of movement (mean onset, -66 ms). Variation in the depth of modulation as a function of the direction of the movement, flexion or extension, was observed in only a very small proportion of the modulated units (16/117); most showed no relationship to direction. It is suggested that, in this experimental situation, much of the modulation appears to occur at a pre-cortical level since there was no relationship between the pattern of discharge of cells in relation to movement alone and the pattern of movement-related gating of their responses to the air puff. Effects which might be consistent with a cortical origin for the modulation were only infrequently observed. The present results are strikingly similar to those obtained using the evoked potential method, and thus support the hypothesis that, in this task of rapid elbow movements, movement modulates the transmission of cutaneous signals from the hairy skin of the distal forelimb to primary somatosensory cortex in a nonspecific and widespread fashion. 相似文献
70.
Jeri W. Nieves Felicia Cosman Chris Mars Robert Lindsay 《Calcified tissue international》1992,51(5):352-355
Summary Forearm bone mineral density (BMD) was measured at proximal and distal sites by 125I single photon absorptiometry (SPA) and by dual energy X-ray absorptiometry (DXA) in 67 consecutive subjects, aged 18–75 years. Correlations and regression equations between these two techniques were determined. All forearm measurements were significantly correlated with each other (r=0.599–0.926; P0.0001). Although SPA and DXA correct for fat in different ways, we found similar correlation and regression equations in women with body mass index measurements above and below the mean. In addition, forearm measurements by both techniques were moderately correlated with vertebral spine and hip BMD. We conclude that overall, SPA forearm measurements in a population can be calibrated to DXA measurements if necessary, and that DXA forearm measurements are as predictive of the remainder of the skeleton as SPA measurements. 相似文献