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81.
Little is known about biological predictors of treatment response in panic disorder (PD). In the present study heart rate, blood pressure, plasma cortisol and plasma MHPG were investigated at baseline in a sample of 44 PD patients as possible predictors for nonresponse to treatment. We used a strict definition of nonresponse to find patients who did not respond at all after 12 weeks of treatment with brofaromine or fluvoxamine. Patients were considered nonresponders when they fulfilled two criteria: they did not show a 50% reduction of agoraphobic avoidance and they still experienced panic attacks at endpoint. The variables that differed significantly between the groups were used to predict nonresponse to drug therapy. Using this strict definition of nonresponse, 15 patients (32.6%) were considered nonresponders. These patients were characterised by a higher plasma MHPG concentration and a higher heart rate at baseline. These variables were subsequently used to predict nonresponse.  相似文献   
82.
细胞内钙信号的变化调节血管平滑肌细胞增殖   总被引:4,自引:0,他引:4  
目的探讨细胞内钙信号的变化对大鼠血管平滑肌细胞(VSMC)增殖作用的影响及其对细胞内信号转导机制的变化。方法以培养的大鼠VSMC为模型,用雷尼丁(RY)剌激VSMC内贮Ca2 释放入胞浆,用3H亮氨酸及3H胸腺嘧啶掺入量作为反应VSMC增殖的指标,加入不同的细胞内信号转导阻断剂,观察对RY效应的影响。结果与对照组相比,RY浓度依赖性地促进细胞内游离钙浓度的增高,差异显著(P<0.05或0.01)。RY剌激组蛋白核酸合成速率明显增高,与对照组相比差异显著(P<0.01);尼卡地平(Nicardipine),蛋白激酶C抑制剂(H7),钙调素激酶(CaMPK)抑制剂(W7)和丝裂素活化蛋白激酶(MAPK)抑制剂(PD98059)能明显抑制RY介导的VSMC蛋白核酸合成速率增高,与RY剌激组相比差异显著(P<0.01)。结论细胞内钙信号的变化明显促进VSMC增殖,但其效应可能通过Ca2 、PKC、MAPK来介导。钙离子拮抗剂可抑制血管平滑肌细胞增殖。  相似文献   
83.
Neck lumps can often present a diagnostic dilemma, with a wide pre-operative differential diagnosis. We present an unusual case of an intramuscular haemangioma arising in the sternocleidomastoid muscle. Pre operative diagnosis is often difficult, as these lesions are extremely rare in the head and neck region and only few sporadic cases have been reported in the literature. We report the presentation diagnosis and management of intramuscular haemangiomas of the sternocleidomastoid muscle.  相似文献   
84.
AbstractBackground: Posterior acromioclavicular dislocation is rare. Dislocation associated with fracture of the clavicle and simultaneous entrapment of the lateral end of the clavicle by trapezius muscle has not been reported. Posterior dislocation occurs frequently owing to forceful move of the scapula anteriorly and superiorly or from direct force applied to the lateral end of the clavicle and this may be associated with clavicular fracture. In acute dislocations, open reduction, internal joint stabilization and soft tissues reconstruction have been recommended.Case Study: Acute posterior dislocation occurred in a 32-year-old man. The lateral end of the clavicle was displaced posteriorly and inferiorly, and firmly entrapped in trapezius muscle. The clavicular fracture was undisplaced. The coracoclavicular ligaments were stretched but intact. Open reduction was secured with two smooth Kirschner wires. The disrupted soft tissues were repaired. The clavicular fracture was not explored. Shoulder movement started at 6 weeks. Wires were removed. 10 years later he had pain-free, unrestricted shoulder movement, and the radiographs showed wellreduced, essentially normal acromioclavicular joint.Conclusion: Open reduction, internal joint stabilization and soft tissue reconstruction will result in return and long lasting unrestricted pain-free function of the shoulder.  相似文献   
85.
100例2型糖尿病患者交感神经皮肤反应研究   总被引:1,自引:0,他引:1  
目的探讨交感神经皮肤反应(SSR)检测在评价2型糖尿病(T2DM)自主神经损害中的价值.方法对100例T2DM患者进行SSR检测,30例健康志愿者作为对照.结果2组SSR的起始潜伏期、N波潜伏期、波幅、面积比较差异有显著性意义(P<0.05),P波潜伏期差异无显著性意义(P>0.05).T2DM组72例(72%)患者至少有一肢SSR异常.血糖控制满意组和血糖控制不良组比较,起始和N波潜伏期差异有统计学意义(P<0.05),波幅和面积无显著性意义(P>0.05).T2DM组病程<5年与病程≥5年比较,潜伏期、波幅、面积差异均无统计学意义(P>0.05).结论SSR可作为评价T2DM自主神经损害的客观电生理指标;T2DM患者SSR与血糖控制水平相关,与病程无关.  相似文献   
86.
OBJECTIVE: To indicate whether the double peaked N(1) to gaps in continuous white noise is a composite of onset and offset responses to transients or whether it reflects higher processing such as change or mismatch detection and to assess the role of attention in this process. METHODS: Evoked potentials were recorded to two binaural stimulus types: (1) gaps of different durations randomly distributed in continuous white noise; and (2) click pairs at intervals identical to those between gap onsets and offsets in the continuous noise stimulus. Potentials to these stimuli were recorded while subjects read a text and while detecting gaps in noise or click pairs. RESULTS: Potentials were detected to all click pairs and to gaps of 5 ms or longer, corresponding to the subjects' psychoacoustic gap detection threshold. With long gap durations of 200-800 ms, distinct potentials to gap onset and gap offset were observed. The waveforms to all click pairs and to offsets of long gaps were similar and single-peaked, while potentials to gaps of 10 ms and longer, and potentials to onsets of long gaps were double-peaked, consisting of two N(1) negativities, 60 ms apart, irrespective of gap duration. The first (N(1a)), was more frontal in its distribution and similar to that of clicks. The second (N(1b)) peak's distribution was more central/temporal and its source locations and time course of activity were distinct. No effects of attention on any of the varieties and constituents of N(1) were observed. CONCLUSIONS: Comparing potentials to gap onsets, to click pairs and to gap offsets, suggests that potentials to gap onsets involve not only sound onset/offset responses (N(1), N(1a)) but also the subsequent pre-attentive perception of the cessation of an ongoing sound (N(1b)). We propose that N(1b) is distinct from change or mismatch detection and is associated with termination of an ongoing continuous stimulus. We propose to call it the N(egation)-process. SIGNIFICANCE: A constituent of the N(1) complex is shown to be associated with the pre-attentive perception of termination of an ongoing stimulus and to have distinct scalp distribution and intracranial sources.  相似文献   
87.
Dual-energy X-ray absorptiometry (DXA) and quantitative ultrasound (QUS) are the accepted modalities for the evaluation of fracture risk in the clinical setting. However, neither method provides a direct measurement of bone mechanics. In this study, we investigated a prototype device, known as a mechanical response tissue analyzer (MRTA), which provides direct mechanical measurements of mechanical properties of bone. A total of 56 healthy volunteers (20 men and 36 women) between the ages of 18 and 83 were recruited. The MRTA was used to measure the cross-sectional bending stiffness (EI) of the ulna bone. Axial speed of sound (SOS) at the ulna bone was determined by QUS; bone mineral content (BMC) and bone mineral density (BMD) were determined by DXA. Correlations, regression analysis, and analyses of variance (ANOVAs) were used to compare the three modalities. These analyses revealed that although there are strong linear relationships among the data collected by the various technologies, the bone properties reflected by MRTA are not fully explained by DXA and QUS. We conclude that the total information conveyed by MRTA measurements is unique. Further research is needed to delineate the different qualities of bone strength that are captured by MRTA, but not by DXA or QUS.  相似文献   
88.
Abstract Myotonic dystrophy type 1 (DM1) is an autosomal dominant disease caused by a trinucleotide repeatexpansion, cytosine-thymine-guanine (CTG)n, in the 3′ untranslated region of a gene encoding the myotonic dystrophy protein kinase (DMPK). To correlate CTG expansion and protein expression, we studied muscle specimens from 16 adult DM1 patients using three anti-DMPK antibodies for immunoblotting. We estimated the amount of the full-length DMPK (85 kDa) in muscle biopsies from normal controls and from DM1 patients carrying different (CTG)n expansions. We found that DMPK concentration was decreased to about 50% in DM patients’ muscles; the protein decrease did not seem correlated with the CTG repeat length. However, the fibre type composition in skeletal muscle seemed somehow to affect DMPK decrease, as the lowest level of the enzyme was found in patients with the lowest content of type 1 fibre.  相似文献   
89.
PURPOSE: This study compared the near phoria measurement using the Bernell muscle balance card with and without prism neutralization, using both trial frame and phoropter correction, and compared with the conventional Maddox rod method. METHODS: Forty young normal Chinese adults had their near phoria measured with trial frame correction using the conventional muscle balance card method (method 1). Any deviation was compensated with a prism bar as an alternative approach (method 2). The conventional Maddox rod method (method 3) was also carried out for comparison. These three methods were repeated with phoropter correction and considered as methods 4, 5 and 6. RESULTS: The phorias obtained from these six methods were not significantly different from each other (repeated measures anova, p > 0.05). More than half of the subjects were exophoric. Although the difference in phoria was not significant, phoria measurement using phoropter correction yielded a greater coefficient of variation. CONCLUSIONS: Near phoria measurement using the muscle balance card conducted with trial frame correction was less variable, and was also more natural and similar to a real reading situation. The use of prism for compensation did not affect the phoria results. Exophoria seems to be more common than esophoria in young Chinese adults.  相似文献   
90.
Klein [Klein, A. S. (2006). Separating transducer nonlinearities and multiplicative noise in contrast discrimination. Vision Research, 46, 4279-4293] questions the existence of intrinsic singularities in two-alternative force-choice (2AFC) Signal Detection Theory (SDT) models, suggesting that the singularities found in Katkov et al. [Katkov, M., Tsodyks, M., & Sagi, D. (2006a). Singularities in the inverse modeling of 2AFC contrast discrimination data. Vision Research, 46, 259-266; Katkov, M., Tsodyks, M., & Sagi, D. (2006b). Analysis of two-alternative force-choice Signal Detection Theory model. Journal of Mathematical Psychology, 50, 411-420] are due to discarding higher order terms in the Taylor expansion of d' and/or limited to steep psychometric functions. Here we provide some simple intuitive examples that illustrate the results described in Katkov et al. (2006a, 2006b). We show, for the constant noise model, that singularities exist when exact values of d' are computed and that the singularities are not limited to steep psychometric functions. In these cases the disambiguation of the different models requires millions of trials.  相似文献   
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