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21.
To analyse the effect of concomitant cognitive or motor task performance on balance control in Parkinson's disease (PD), we performed a posturographic study in 24 PD patients and in 20 sex- and age-matched control subjects. Postural sway was measured with eyes open (EO) and eyes closed (EC) during quiet stance and during performance of calculation or motor sequence of thumb opposition to the other fingers. No difference of centre of foot pressure (COP) parameters was observed during quiet standing (either EO or EC) between patients and controls, but visual deprivation induced in both groups a worsening of postural stability. COP area was significantly increased in PD patients during dual task performance, whereas no difference of COP path and x-y axes was observed. The effects induced by the performance of cognitive or motor task were significantly more evident in PD patients with clinical evidence of postural instability (presence of prior falls in the history). This study demonstrates that dual task interference on postural control can be observed in PD patients during performance of cognitive as well as motor tasks. The balance deterioration during dual task performance was significantly enhanced in patients with history of prior falls. These findings have some implications for the strategies to be used in reducing the risk of fall in PD. 相似文献
22.
23.
LI-JEN LIN JIUNN-LEE LIN LING-PING LAI JYH-HONG CHEN YUNG-ZU TSENG WEN-PIN LIEN 《Pacing and clinical electrophysiology : PACE》1998,21(7):1375-1379
The purpose of this study was to investigate the atrioventricular AV nodal physiology and the inducibility of AV nodal reentrant tachycardia (AVNRT) under pharmacological autonomic blockade (AB). Seventeen consecutive patients (6 men and 11 women, mean age 39 ± 17 years) with clinical recurrent slow-fast AVNRT received electrophysiological study before and after pharmacological AB with atropine (0.04 mg/kg) and propranolol (0.2 mg/kg). In baseline, all 17 patients could be induced with AVNRT, 5 were isoproterenol-dependent. After pharmacological AB, 12 (71 %) of 17 patients still demonstrated AV nodal duality. AVNRT became noninducible in 7 of 12 nonisoproterenol dependent patients and remained noninducible in all 5 isoproterenol dependent patients. The sinus cycle length (801 ± 105 ms vs 630 ± 80 ms, P < 0.005) and AV blocking cycle length (365 ± 64 ms vs 338 ± 61 ms, P < 0.005) became shorter after AB. The antegrade effective refractory period and functional refractory period of the fast pathway (369 ± 67 ms vs 305 ± 73 ms, P < 0.005; 408 ± 56 ms vs 350 ± 62 ms, P < 0.005) and the slow pathway (271 ± 30 ms vs 258 ± 27 ms, P < 0.01; 344 ± 60 ms vs 295 ± 50 ms, P < 0.005) likewise became significantly shortened. However, the ventriculoatrial blocking cycle length (349 ± 94 ms vs 326 ± 89 ms, NS) and effective refractory period of retrograde fast pathway (228 ± 38 ms vs 240 ± 80 ms, NS) remained unchanged after autonomic blockade. Pharmacological AB unveiling the intrinsic AV nodal physiology could result in the masking of AV nodal duality and the decreased inducibility of clinical AVNRT. 相似文献
24.
赵崇侃 《北京生物医学工程》1997,(1)
作者介绍了一种动态心率检测电路,它能准确、可靠地检出在运动状态下的人体心率。电路采用两种检测技术,一种为双时值QRS波检测法,另一种为光电脉搏检测法。 相似文献
25.
Korppi M 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2002,110(7-8):515-522
Seven paediatric studies on community-acquired pneumonia with serological methods for both viruses and bacteria have been published, allowing the evaluation of concomitant multiple etiological findings. In these studies, dual viral infection has been present in 0-14%, dual bacterial infection likewise in 0-14%, and mixed viral-bacterial infection in 3-30% of the pneumonia cases. The results confirm former clinical observations that respiratory viruses often pave the way for airway-colonising bacteria. The measured frequency of multiple infections has been dependent on the available test panel, mainly on the tests used for pneumococcal aetiology. Mixed viral-bacterial infections have been especially common in young children under 2 years of age, reflecting the high frequency of respiratory syncytial virus infections and their tendency to induce bacterial co-infections. No microbe-specific viral-bacterial associations have been demonstrated. The clinical implications of mixed viral-bacterial infections, compared with viral infections alone or bacterial infections alone, have so far remained unresolved. Current guidelines recommend antibiotic therapy for all community-acquired pneumonia cases in children. 相似文献
26.
Twelve asthmatics with dual bronchial and skin reactions after allergen challenge received topical treatment with a 5%-indomethacin cream half an hour before and up to 7h after intradermal allergen and histamine injections. The erythema during the first 20 min of the wheal and flare reaction (WFR) was not affected, neither were the diameters of wheals and flares. 40 to 60 min after injection we observed a marked reduction of the erythema in histamine-and allergen-tested skin areas of 10 Patients. This effect lasted up to the 5th h alter injection of high allergen doses. During the hilly developed late cutaneous reactions (LCR) no effect 0f indomethacin on the erythema was observed, the edema of LCR was only insignificantly reduced. These results suggest that the erythema in LCR between the 1st and 4th is caused, at least in part, by local formation of prostaglandins. 相似文献
27.
This paper reports the occurrence of a rare, yet distinct pituitary adenoma which was surgically removed from a 42-year-old male with both clinical and biochemical evidence of acromegaly and mild hyperprolactinaemia. The monomorphic adenoma consisted of mature cells which were ultrastructurally indistinguishable from those of a prolactinoma. Electron immunocytochemistry, including a series of double-labelling techniques using selected colloidal gold particles as markers, indicated the presence of a pituitary adenoma in which the cells were capable of simultaneously producing growth hormone and prolactin and packaging them within the same secretory granule. This is thought to represent a mammosomatotroph cell adenoma. 相似文献
28.
Allelic exclusion of {alpha} chains in TCRs 总被引:2,自引:0,他引:2
Although the ß chains of ß+ T cells exhibitallelic exclusion it has recently been shown that 20–30%of such cells express both chain alleles on their surface.Potentially these cells have dual specificity, and it has beensuggested that they may play a role in autoimmunity and alloreactlvtty.The analysis presented in this paper examines critically thepossibility that the observed violation of allelic exclusionof chain expression arises as a natural consequence of a chainrearrangement and intrathymlc positive selection. It is concludedthat, subject to certain identified conditions being satisfied,the observed frequency of T cells expressing two chains iscompatible with such a mechanism. However, It is an essentialassumption of the theory that, of the two ß chaincomplexes on these cells, only one mediates positive selection.It follows that to what extent both receptors are actually functionaldepends on whether an ß chain complex that has failedto satisfy the criterion of positive selection can mediate antigenrecognition in the periphery. In principle the answer to thisquestion may be different if one is considering autoreactlvltyor alloreactlvlty. Finally, attention is drawn to the apparentdiscrepancy between the frequency of peripheral T cells expressingtwo chains and the failure to find T cell clones of this phenotype.Possible explanations are discussed. 相似文献
29.
DAVID R. HOLMES JR. DAVID L. HAYES JOEL E. GRAY JOHN MERIDETH 《Pacing and clinical electrophysiology : PACE》1986,9(3):360-370
The effects of magnetic resonance imaging were assessed on four dual chamber and two single chamber pulse generators. The tests were performed with a resistive, water-cooled magnet operating at 0.15 T. The 6.4-MHz radiofrequency (RF) field was operated at a maximum power of 1,000 watts with a period adjusted from 130 to 500 ms. Reed switch closure occurred in all six pulse generators tested when placed near the entrance of the magnetic resonance imaging scanner, and the generators reverted to asynchronous operation unless programmed to the "magnet off" mode. None of the pulse generators exhibited any alterations in programmed parameters or in the ability to be reprogrammed after RF pulsing. When the RF field was turned on, there was no change in the asynchronous paced cycle length in four pulse generators; however, during RF scanning there was rapid cardiac stimulation at the RF pulse period in one single chamber and one dual chamber pulse generator. 相似文献
30.
IntroductionReduced port laparoscopic surgery using an umbilical zigzag incision is comparable to conventional multiport laparoscopic surgery. This method is associated with improved cosmesis and decreased wound pain.Presentation of caseA 67-year-old man visited our hospital. He presented emergency room with a chief complaint of right lower abdominal pain by walking. The patient was diagnosed Meckel’s diverticulitis by computed tomography (CT). At first, antibiotics therapy and fasting were performed. Three months later, the patient underwent resection of Meckel’ diverticulum with zigzag transumbilical laparoscopic surgery. The patient’s postoperative course was good, and he rarely felt wound pain. The patient started oral intake three days after surgery, and was discharged 10 days after surgery.DiscussionZigzag transumbilical laparoscopic surgery is very useful for resection of the small intestine. This method is associated with improved cosmesis and decreased wound pain. In the case of Meckel’s diverticulitis, we suggest that interval resection of Meckel’s diverticulum was very useful as it was an operation that could be performed easily.ConclusionReduced port laparoscopic surgery using an umbilical zigzag incision is considered to be an excellent technique in terms of operability and aesthetic outcomes. 相似文献