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Summary. A new apparatus which measures the blood pressure in the finger continuously and yet not invasively was tested for its usefulness during exercise. It was compared with upper arm measurements in 23 volunteers during prolonged bicycle ergometry. Simultaneously, a pulse plethysmogram was recorded from another finger of the same arm, whereas in six additional volunteers Doppler measurements were carried out on the radial artery. The results show that finger systolic pressure ceased to rise at about 40% of maximal exercise; the difference with the continuously rising systolic pressure in the upper arm becoming significant at 140 W. At the same time the amplitude of the finger plethysmogram became significantly higher than its initial value, indicating distinct cutaneous vasodilation, whereas the volunteers also became hot and started to perspire. However, the radial artery ‘flow’, deduced from the Doppler measurements, did not change significantly during exercise. It increased sharply and markedly in the cooling down period. Simultaneously with this increase in flow, HR and both systolic blood pressures fell drastically whereas the plethysmography amplitude remained about stable at its raised level. The results fit in with the idea that a compromise is achieved between the need for muscle activity and the need for temperature regulation. It is concluded that the Finapres functions well during exercise, but that the systolic pressure in the finger is not representative for its more central counterpart during cutaneous vasodilation. It is argued that opening up of AVAs may contribute to this pressure effect. 相似文献
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1 The internal anal sphincter (IAS) has a spontaneous tone and is the main contributor to the maintenance of faecal continence. The spontaneous resting tone exhibited by the sphincter can be modified by neurotransmitters from the autonomic and enteric nervous systems. 2 In this review, the influence of the sympathetic and parasympathetic nervous systems on IAS tone are discussed and the putative roles of nitric oxide, carbon monoxide, vasoactive intestinal peptide and adenosine triphosphate in non‐adrenergic non‐cholinergic transmission are considered. 3 Faecal incontinence is a common condition that places a heavy financial burden on the health service and severely affects patients’ quality of life. Resting anal pressure is reduced in patients with faecal incontinence and agents that increase sphincter tone tend to relieve symptoms. The results of clinical studies of the use of phenylephrine to treat faecal incontinence are reviewed. 4 It is concluded that the IAS is a potential target for drug development for the treatment of faecal incontinence. 相似文献
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目的评价不同治疗方法对慢性牙周炎的临床效果。方法对90例慢性牙周炎患者,随机分成三组:龈上洁治术 抗生素组(A组),单纯龈上洁治术组(B组)和单纯抗生素组(C组)。分别给予不同的治疗,在治疗后1周、2周和4周记录牙周袋探诊深度(PPD)、探诊附着水平(PAL)、菌斑指数(PLI)、龈沟出血指数(SBI)。结果治疗1周和2周后各指标显著减轻(P<0.05),2周比1周减轻更明显(P<0.05),4周与2周比较无明显差异(P>0.05),A组各指标减轻比B组显著(P<0.05);B组比C组疗效显著(P<0.05)。结论A组作用优于B组(P<0.05),B组优于C组(P<0.05)。 相似文献
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J. Ludwig T. Halbrügge G. Vey J. Walter K. -H. Graefe 《European journal of clinical pharmacology》1989,37(5):493-500
Summary The total body clearance and fractional extraction of isoprenaline (ISO) have been determined, and the relation between these parameters and cardiac output established. Whether desipramine, an inhibitor of neuronal uptake, altered the plasma catecholamine response to ISO was also investigated.Seven healthy subjects were given i.v., infusions of ISO in two, consecutive 25-min periods, at constant dose rates of 31–43 and 80–124 pmol·kg–1·min–1, respectively. The total-body (ER), pulmonary (ERp) and forearm (ERf) fractional extractions and the total body clearance (CL) of ISO were obtained from measurements of cardiac output and the steady-state ISO concentration in mixed central venous, arterial and forearm venous plasma.ISO-induced increases in cardiac output resulted in increases in CL, decreases in ER and no consistent change in ERf. ERp did not differ from zero. ISO also produced a dose-dependent increase in the mixed venous plasma concentrations of noradrenaline and 3,4-dihydroxyphenylglycol (DOPEG), and a decrease in that of adrenaline. Pretreatment with desipramine did not alter any of the pharmacokinetic parameters of ISO. Desipramine, however, reduced the mixed venous baseline plasma levels of noradrenaline (47%) and DOPEG (40%), and tended to reduce that of adrenaline (34%). It enhanced the plasma noradrenaline response 2.4-fold, abolished the plasma DOPEG response and did not alter the plasma adrenaline response to ISO.Hence, owing to its haemodynamic effects, ISO modifies its own pharmacokinetics which involve non-neuronal removal processes only. The increased DOPEG in plasma resulting from the ISO-induced increase in noradrenaline release was presynaptic in origin. Desipramine appears to reduce sympathetic activity. The enhancement by desipramine of the ISO-induced increase in plasma noradrenaline points towards recapture by neuronal uptake of at least 58% of the noradrenaline released in response to ISO. 相似文献
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Fluency deficits have been found in different neuropsychological populations, and dissociation of letter initial and category fluency has been demonstrated in right-brain-damaged and Alzheimer patients. Studies on normal controls also indicate that letter initial and category fluency are supported by different brain regions. We studied letter initial and category fluency in 79 left-brain-damaged patients, 18 non-aphasic and 61 aphasic. Our results indicate that brain-damaged patients are significantly impaired in both fluency tasks compared to normal controls, and a difference between letter initial and category fluency emerges from our data. Firstly, only letter initial fluency is more impaired in aphasic than in non-aphasic patients; secondly, many aphasics have normal category fluency and pathological letter initial fluency but the reverse is seldom true and thirdly, only category fluency scores correlate with confrontation-naming scores. It is suggested that strategies to recover words based on a semantic or a phonological prompt are different. A semantic strategy is coherent with the organizational structure of the semantic system and corresponds to the normal way in which we recover words whereas a phonological strategy is quite unusual and it is not used for actual communication. 相似文献
8.
These studies demonstrate the presence of pontomedullary areas in the rat brainstem which, when stimulated electrically, serve to set postural muscle tone in the hindlimbs. Low amplitude stimulation of the dorsal tegmental field (DTF) was found to inhibit postural muscle tone and, in some rats, was found to decrease mean arterial pressure. Low amplitude stimulation of the ventral tegmental field (VTF) was found to increase postural muscle tone and, in all cases tested, was found to increase mean arterial pressure. 相似文献
9.
E. SCHÜTZ M. LUY-KALTEFLEITER M. KALTEFLEITER M. BURDELSKI† B. RINGE V. W. ARMSTRONG M. OELLERICH 《European journal of clinical investigation》1996,26(10):907-916
Abstract. Post-transplant assessment of early graft function has become an essential part of monitoring, especially when deciding on retransplantation. If primary non-function is indicated, retransplantation is inevitable; early graft dysfunction may be related to subsequent complications. In a prospective study in 84 patients after orthotopic liver transplantation (OLT) we measured aspartate aminotransferase (AST), alanine aminotransferase (ALT), glutamate dehydrogenase (GLDH), bilirubin (BIL), prothrombin time, MEGX formation, hyaluronic acid (HA) and soluble interleukin-2 receptor (sIL-2R) concentrations during the first 2 postoperative weeks; graft outcome was followed over 4 months. The aim of this study was to determine whether graft survival could be predicted by such variables early after OLT. Compared with patients with stable graft function (n= 25), patients with post-transplant icteric cholestasis (n= 30) exhibited no difference in graft survival, despite a decrease in MEGX formation to a nadir median of 12 μgL-1 on day 10. Patients with rejection (n= 8) and septicaemia (n= 6) showed a marked decrease in MEGX values and an increase in HA and sIL-2R concentrations between postoperative days 3 and 7. Patients with primary non-function (PNF; n= 5) were characterized by strongly reduced MEGX formation (median 4 μgL) and increased HA values (median 2300 μgL-1) on day 3 after OLT. A total of 24/84 grafts were lost within 120 days. In a survival analysis using the Cox proportional hazards regression, HA and MEGX values on day 1 were the only independent variables entering the model that showed an adequate prognostic sensitivity. At cut-off points of 22 μgL-1 (MEGX) and 730 μgL-1 (HA) the combined use of these parameters in a parallel approach yielded a sensitivity of 58% with a corresponding specificity of 95% for 120-day graft survival. These findings suggest that the inclusion of MEGX and HA in postoperative monitoring of OLT patients may be helpful in the early prediction of graft survival. 相似文献
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