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Although most prostate cancer (PCa) patients nowadays are diagnosed at an early stage of disease, unfortunately still a significant number of patients will develop advanced PCa or will be diagnosed at an advanced (or metastatic) stage of disease. The group of patients showing the highest increase in incidence are those with rising prostate specific antigen (PSA) after radical therapy.In the last quarter of 2004, a Medline search has been performed targeting publications on patients diagnosed with advanced PCa, as well as with PSA relapse after previous radical therapy. This review aims at providing guidance to optimise hormone therapy in those selected groups of patients by addressing three pivotal questions; (i) who should receive hormonal treatment, (ii) what type of hormonal therapy should the patient be offered and (iii) what is the best timing of starting hormonal treatment.In patients relapsing after radical therapy, the PSA doubling time (PSA DT) has become a critical instrument to distinguish patients to have innocuous PSA evolution from patients at high risk for disease progression. A PSA DT of 3 months seems to be the cut-off point for identifying patients at risk. Therefore patients with a PSA DT of less than 3 months should be advised to initiate hormonal therapy. Antiandrogen monotherapy may be considered in this setting as it has been shown to delay progression; however, significant survival data are not yet available. Whether luteinising hormone releasing hormone (LHRH) agonists should be given continuously or intermittently (IHT) remains subject of debate.Surgical castration has been the standard of care in patients diagnosed with advanced PCa. Currently, LHRH agonists have become the preferred way of suppressing testosterone.Combination of an antiandrogen and a LHRH agonist (CAB) shows a modest benefit over LHRH agonist monotherapy. As CAB leads to increased side effects and costs, LHRH agonist monotherapy is preferred in the majority of patients.Conflicting data have been published concerning the optimal timing of LHRH agonist therapy. So it is not clear whether LHRH agonist therapy should be started immediately or deferred until appearance of symptoms. When initiating continuous hormone therapy, patients should be carefully monitored for the risk of long term androgen deprivation (anaemia, osteopenia and osteoporosis).  相似文献   
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Summary The muscle pronator teres was studied by surface electromyography during elbow flexion in a horizontal plane. The forearm was in semi-pronation and movement was performed at various velocities. A quantitative comparison was made between pronator teres activity and two main elbow flexors, biceps brachii and brachioradialis.The mean timing of the onset of activity was constant: biceps brachii was activated first followed by pronator teres and brachioradialis, and the lower the velocity of flexion, the earlier was the onset of biceps brachii activity.There was a linear relationship between the integrated EMG from each muscle and the work done. However, this relationship was less exact for pronator teres and brachioradialis at low values of work, a finding which opens questions about the generality of this relationship and about the muscle equivalent concept.Pronator teres appears to participate in elbow flexion besides its role in pronation.Despite similar anatomical peculiarities, pronator teres does not behave in the same way as anconaeus or popliteus and, above all, it is not the sole muscle active in slow movement. Thus, all the stocky mucles lying close to an articulation do not behave in the same way.  相似文献   
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Summary Upper lip, lower lip, and jaw kinematics during select speech behaviors were studied in an attempt to identify potential invariant characteristics associated with this highly skilled motor behavior. Data indicated that speech motor actions are executed and planned presumably in terms of relatively invariant combined multimovement gestures. In contrast, the individual upper lip, lower lip, and jaw movements and their moment-to-moment coordination were executed in a variable manner, demonstrating substantial motor equivalence. Based on the trial-to-trial variability in the movement amplitudes, absolute positions, and velocities of the upper lip, lower lip, and jaw, it appears that speech motor planning is not formulated in terms of spatial coordinates. Seemingly, object-level planning for speech may be encoded in relation to the acoustic consequences of the movements and ultimately with regard to listener's auditory perceptions. In addition, certain temporal parameters among the three movements (relative times of movement onsets and velocity peaks) were related stereotypically, reflecting invariances characteristic of more automatic motor behaviors such as chewing and locomotion. These data thus appear to provide some additional insights into the hierarchy of multimovement control. At the top of the motor control hierarchy, the overall plan appears to be generated with explicit specification of certain temporal parameters. Subsequently, based upon the plan and within that stereotypic temporal framework, covariable adjustments among the individual movements are implemented. Given the results of previous perturbation studies, it is hypothesized that these covariable velocity and amplitude adjustments reflect the action of sensorimptor mechanisms.  相似文献   
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Summary Previous speech kinematic studies have demonstrated systematic timing relations among the upper lip, lower lip, and jaw suggesting the operation of a central pattern generator (CPG). The present study evaluated the consistency of these timing relations following unanticipated perturbation of the lower lip. Using this approach, it was also possible to evaluate the influence of sensory information on the timing of motor output and subsequent coordination of the multiple speech movements. Perturbations were applied to the lower lip during the closing movement associated with the first p in sapapple. Muscle activity and movements of the upper lip, lower lip, and jaw were obtained. Changes in movement displacement, velocity and duration, the timing and sequencing of peak velocities, EMG area, and EMG rise time were analyzed for the control and load conditions. Similar to previous perturbation results, significant magnitude compensations from the muscles and movements of the upper lip, lower lip, and jaw were observed. In contrast, movement durations and the sequencing of peak velocities were relatively unaffected by the lower lip load. The timing of peak EMG amplitude and consequently the timing of peak closing velocity for all structures (UL, LL, and J) occurred earlier relative to the preceding opening movement. These results are consistent with the interaction of phasic sensory input with centrally-driven commands resulting in a phase-advanced motor output. Further, as the timing of one structure is modified so were all the functionally-linked components thereby maintaining the necessary coordination. As in other rhythmic motor behaviors such as locomotion and chewing, there appears to be a centrally patterned framework for speech movement coordination.  相似文献   
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Twelve rats received injections of 5,7-dihydroxytryptamine into the dorsal and median raphe nuclei; 12 rats received sham lesions. The rats were then trained for 60 sessions under a discrete-trials fixed-interval schedule (peak procedure). In half the trials, a reinforcer became available 40 s after trial onset, and the trial was terminated upon reinforcer delivery; the remaining trials were 120 s in duration, and reinforcement did not occur in these trials. Performance during the 120-s trials was characterized by increasing response rate during the first 40 s of the trial, declining response rate between 40 s and 80 s, and a secondary increase in response rate during the final 40 s of the trial. The lesioned group showed a broader spread of the response rate function than the control group (time between attainment of 70% of the peak response rate and subsequent decline of response rate below this level); however, the peak response rate and the time from trial onset until attainment of the peak response rate did not differ significantly between the groups; the spread/peak-time ratio was significantly greater in the lesioned group than in the control group. The levels of 5-hydroxytryptamine (5HT) and 5-hydroxyindoleacetic acid in the parietal cortex, hippocampus, amygdala, nucleus accumbens and hypothalamus were markedly reduced in the lesioned group, but the levels of noradrenaline and dopamine were not significantly affected by the lesion. The results confirm the involvement of 5HTergic function in timing behaviour.  相似文献   
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83例硅油取出时机及并发症的临床分析   总被引:3,自引:1,他引:3  
目的 分析硅油充填的时间与视网膜复位的关系及硅油在眼内存留时间和硅油并发症产生的关系。方法 回顾分析83例(83只眼)行硅油取出术患者的临床资料及随访记录。结果 行硅油取出的时间为3~13个月,平均8个月。在无发生硅油相关的并发症的条件下,78例在取出硅油之后,视力无明显改变或稍有提高。角膜变性的病例,在硅油取出之后,其混浊情况无明显改变。11例青光眼在硅油取出之后眼压恢复正常者8例,5例在硅油取出之发生了复发性视网膜脱离。结论 硅油取出的最佳时机是3~6个月。硅油取出可以缓解硅油并发症的发展。硅油取出术的并发症主要为复发性视网膜脱离、脉络膜出血、脉络膜脱离、视网膜出血及低眼压。  相似文献   
9.
目的探讨腹股沟斜疝腹腔镜手术治疗时机。:回顾性分析2003年6月本院收治的167例小儿方法腹股沟斜疝(A组为6月~12月龄患儿,B组为13月龄~13岁)的临床资料。结果:两组病例在多次嵌顿史,术中发现隐性疝,手术并发症,手术时间均无统计学差别(P>0.05)。:腹股沟斜疝患儿疝嵌顿的发生率结论和手术复杂程度并未随年龄的增加而降低,对于小儿腹股沟斜疝,手术时机应适当放宽对于≥6月龄的患儿,不应该受年龄的限制,及早采取手术治疗。  相似文献   
10.
多发性创伤仍是人类健康的重要威胁之一。长骨骨折是多发伤最常见的伴发损伤。近年来,随着大量临床研究工作的深入,此类患者的诊疗策略已发生了巨大的变化。但关于如何确定多发伤患者肢体骨折内固定的时机仍然充满争议。主要的争议存在两种外科处理方法—早期全面治疗和损伤控制骨科之间如何选择。本文通过回顾相关的文献,综述了对最佳手术时机的认识及演变,简要讨论了严重多发性创伤患者长骨骨折内固定手术时机这个充满争议的问题,以期为此类患者的处理提供帮助.  相似文献   
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