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1.
宫颈癌对妇女健康构成严重威胁,人乳头瘤病毒感染与宫颈病变及宫颈癌的发生密切相关。关于宫颈癌发生发展的机制仍在研究中。近年研究发现一种多功能核蛋白,即死亡结构域相关蛋白(death domain associated protein,Daxx),其与细胞内蛋白或病毒蛋白相互作用,参与调节细胞凋亡、转录调控、抗病毒等细胞活动,在不同途径中发挥不同的生理或病理作用。通过对Daxx功能及其作用机制的研究有助于进一步阐明宫颈癌发生发展的机制,有助于发现新的预防和治疗方法。综述Daxx的一般特性和研究现况及其在宫颈病变的研究进展。  相似文献   
2.
The aim of this pilot study was to examine the role of the striatum and cerebellum in the adaptation to a novel movement within a sequence of practiced movements using a motor learning paradigm. The performance of patients in the early or advanced stages of Parkinson's disease (PD) and of patients with damage to the cerebellum (CE) was compared, respectively to a group of aged and young matched controls on an adapted version of the Mirror-Tracing Test. In this task, subjects were required to trace a series of complex figures in two conditions: (1) a Practiced condition, in which the figures were composed of the juxtaposition of three simple designs that were extensively practiced before; and (2) a Mixed condition in which triads were created by replacing the last simple figure of the triads in the Practiced condition by a new simple figure that had never been traced individually before. Results showed that all clinical groups were slower than controls at tracing the Practiced triads. Most interestingly, however, only patients in the advanced stages of PD showed increased completion time to trace the triads in the Mixed condition. This suggests that a bilateral striatal dysfunction affects the ability to adapt to a novel motion within a sequence of practiced movements. Although exploratory, these results support a functional dissociation between the striatum and cerebellum in acquiring visuomotor skilled behaviors.  相似文献   
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Naloxone, an opioid peptide antagonist, has been reported to facilitate voiding in neurologic bladder disorders, but its effects on the neural micturition reflex arc are poorly understood. We studied the effect of naloxone in 34 male adult cats, spinalized at C5-C6 level 7 to 119 days previously. Each cat served as its own control. The following tests were performed: Urethral pressure profiles, cystosphincterograms with the urethro-vesical junction opened and closed and mechanograms of the detrusor, and the circular and longitudinal urethral muscles. The study included (1) the effects of anesthesia of the bladder and pelvic nerve, as well as that of the urethral and pudendal nerves; (2) the action of naloxone; and (3) the action of oxymorphone. Our results demonstrated that naloxone (1) increased somatic (osteotendinous and nociceptive) reflexes and aggravated spasticity; (2) increased vegetative micturitional and sexual reflexes, in particular the urethra-urethral contraction reflex, aggravating the spasmodic contractions of the external sphincter; and (3) increased the frequency and intensity of the mass reflex. In consequence, we suggest that naloxone is contraindicated in cases of spinal cord lesions with detrusor-sphincter dyssynergia syndrome.  相似文献   
5.
A 69‐year‐old man was admitted to Toho University Omori Medical Center complaining of icterus. Abdominal computed tomography, magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography were suspicious of cholangioma of inferior bile duct. Peroral cholangioscopy using narrow band imaging (NBI) was performed and it was possible to diagnose the mucosal spread lesions of cholangioma. Histological findings reflected the endoscopic findings. Mucosal spread lesions of cholangiocarcinoma were successfully diagnosed using the CHF‐B260 for NBI.  相似文献   
6.
The in vitro capacity of sympathetic superior cervical ganglia (SCG) to take up [3H]choline from the extracellular medium, to synthesize acetylcholine from [3H]choline, and to release [3H]acetylcholine in response to a high K+ concentration, were examined in rats throughout a 24-h cycle. Both the release of [3H]acetylcholine and the synthesis of [3H]acetylcholine from [3H]choline exhibited significant diurnal variations, showing maxima during the first half of the night. After these maxima, nocturnal acetylcholine release and synthesis decayed to daytime levels and remained low until the end of the night. [3H]Choline uptake by rat SCG did not vary significantly throughout a 24-h period. A 1.5-h exposure of rats to darkness at the 5th hour of light phase of the daily photoperiod did not change significantly any parameter studied. A 20-min, 5-Hz, electrical stimulation of the preganglionic trunk of SCG excised from rats at noon increased significantly subsequent K+-induced [3H]acetylcholine release but did not change [3H]acetylcholine synthesis. In decentralized SCG of rats subjected to a unilateral SCG decentralization and a contralateral sham-operation 7 days earlier, [3H]acetylcholine release and synthesis were highly reduced or abolished at the decentralized side, while [3H]choline uptake remained unaltered. The present results suggest that an activation of preganglionic rat SCG neurons takes place during the first half of the scotophase.  相似文献   
7.
跳水运动员颈椎损伤的生物力学研究   总被引:1,自引:1,他引:0  
作者通过在新鲜成人颈椎标本上做了椎体静力性负荷和动力性负荷实验,表明颈椎在后伸位应力为前屈位的50%,最大应力位于颈椎4-6,是跳水运动员头颈部入水时引起颈椎致伤的生物力学因素。  相似文献   
8.
Recent studies show comparable results of arthroscopic shoulder stabilization techniques compared with the gold standard open Bankart reconstruction. Great technical advances and ever-increasing surgeon experience have rendered pathology once deemed an indication for open surgery as treatable by arthroscopic means. With this movement toward a more universal application of all-arthroscopic techniques, we might consider the following question: Is there ever a need to open? To answer this question, we must first consider normal anatomy and then appreciate the contribution of deranged pathoanatomy to recurrent instability in each individual case. The surgeon must then determine whether this is best addressed via an arthroscopic or open technique. Arthroscopy, as compared with open stabilization procedures, holds the potential benefits of decreased morbidity rates, early functional rehabilitation, and improved range of motion. Despite potential advantages, arthroscopic stabilization is clearly contraindicated when a significant pathologic lesion contributing to recurrent instability cannot be adequately addressed as a result of the limitations of current techniques or instrumentation. On the basis of this principle, we believe that sizable glenohumeral bone defects remain the only absolute contraindication to an all-arthroscopic approach. Many complicating issues, such as attenuated capsule, humeral avulsion of the glenohumeral ligament lesions, cases of revision surgery, and collision or contact athletes, exist and warrant close attention. We prefer to think of these situations as “challenges” for which both arthroscopic and open surgery should be considered, rather than as true contraindications to arthroscopic shoulder stabilization. We are, by no means, advocating arthroscopic treatment in all cases of shoulder instability, because this would represent a gross oversimplification of the issues at hand. However, we do acknowledge that the steadfast contraindications to arthroscopic shoulder stabilization are decreasing every day.  相似文献   
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10.
Currently, the best treatment option for idiopathic cervical dystonia (ICD) is injection of botulinum toxin (BTX) into the affected muscles, whereas rehabilitative approaches have given disappointing results. We evaluated whether the association of an ad hoc rehabilitative program may improve the clinical efficacy of BTX treatment in a single-center, cross-over, controlled study. Forty patients with ICD were randomly assigned to two different treatment groups: (1) BTX type A (BTX-A) plus a specific program of physical therapy (BTX-PT) or (2) BTX-A alone (BTX-0). Patients in the BTX-PT group showed a longer duration of the clinical benefit (118.8 vs. 99.1 days) and needed a lower dose of BTX at reinjection (284.5 vs. 325.5 units). In addition, they showed more marked reductions in their disability in activities of daily living (-9.7 vs. -4.85 points) and subjective pain (-13.35 vs. 6.95 points) scores. Association of BTX-A therapy with a specific program of physical therapy may improve ICD treatment outcome.  相似文献   
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