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21.
To compare levels of y-seminoprotein (gM-Sm) assayed by original and revised assay systems, blood was obtained every 4 h over a 32-h period from 8 untreated prostate cancer patients. Serum levels of prostate specific antigen (PSA) were also examined. In 6 patients, the coefficient of variation (CV) of the serum levels assayed by the revised assay was significantly different from that of the intra-assay samples. In contrast, the CV of the gM-Sm serum levels assayed by the original assay differed significantly from that of the intra-assay samples in only 2 patients. The fluctuations in gM-Sm assayed by the revised assay were, at least in part, similar to those of the PSA serum levels in all patients. The mean CV of the gM-Sm serum levels assayed by the revised assay was significantly larger than that for levels measured by the original assay. After treatment, the rate of decrease in gM-Sm serum levels determined by the original assay differed from that in the serum levels of PSA and prostatic acid phosphatase. These results indicate that the original assay for gM-Sm do not detect diurnal differences in serum gM-Sm levels, even at levels below 20 ng/ml. These observations indicate that the analysis of data obtained using the original gM-Sm kit should be interpreted with caution.  相似文献   
22.
144例脑血管意外患者死亡时间节律分析   总被引:6,自引:2,他引:4  
目的 揭示脑血管意外死亡的年节律、月相节律以及昼夜节律 ,为临床及时防治提供时间依据。方法 采用流行病学调查方法收集资料 ,用 χ2 检验及圆形分布法来分析资料。结果 ①脑出血死亡时间存在向上半夜集中的昼夜节律 ;②脑梗死死亡时间存在向冬季和下半夜集中的年节律和昼夜节律。结论 脑出血死亡存在昼夜节律 ,脑梗死死亡存在年节律和昼夜节律。  相似文献   
23.
应用拉丁方设计,在不同体重组的大鼠,于不同时辰,对交叉上核采取不同强度的刺激,用放射免疫法测定外周血中皮质酮的含量。其结果显示:各体重组间无显著性差异,不同时辰血浆皮质酮的平均含量各组呈现基本相同的节律性变化,无论何时辰刺激交叉上核使之兴奋,均可显著提高血浆皮质酮的含量。完全损毁交叉上核后72小时血浆皮质酮含量和正常对照组无显著性差异,且其节律性也没有出现明显变化。  相似文献   
24.
Melanophores were studied in tadpoles of the South African clawed toad, Xenopus laevis , during the first week after hatching (stages 46–49) at 25°C. The tadpoles had melanophores with dispersed melanosomes in the light and punctate melanophores in the dark in LD12:12. The melanophores remained punctate in constant dark and the melanosomes remained dispersed in constant light. Lights-out (in the light-time of LD12:12) caused the melanophores to become punctate, which occurred more quickly than the dispersion of melanosomes, which commenced when the lights were turned on (in the dark-time of LD12:12). Melanophores with dispersed melanosomes in tadpoles (in constant light) became punctate in response to a series of melatonin concentrations (0.2–5 ng/ml) in their bathing water irrespective of the time of day melatonin was administered. An image-analysis technique for assessing melanophore responses was tested.  相似文献   
25.
右归饮择时使用对肾阳虚大鼠生长激素昼夜节律的影响   总被引:1,自引:0,他引:1  
目的 探讨右归饮择时用药在肾阳虚证治疗中的意义。 方法 采用放免法 ,以肾阳虚大鼠血清生长激素为指标 ,观察右归饮择时用药的疗效。结果 右归饮择时用药对肾阳虚大鼠症状的改善有一定作用 ,并以卯时用药效果较好。结论 右归饮治疗肾阳虚证应当提倡择时用药。  相似文献   
26.
目的 研究重度充血性心力衰竭患者血流动力学的昼夜节律改变.方法 选择2005年12月至2006年6月在南京中医药大学无锡附属医院心内科住院的重度充血性心力衰竭患者120例为心衰组,同期门诊体检的无心血管疾病者20名为对照组,采用生物阻抗法每小时1次动态监测心率(HR)和每搏输出量(SV).结果 心衰组与对照组HR、SV均存在昼夜节律,但分布规律存在差异,心衰组HR明显快于对照组(P<0.5),而SV明显低于对照组(P<0.05);对照组HR与SV呈正相关(P<0.01),而心衰组HR与SV总体上也呈正相关(P<0.01),但在凌晨100~400之间,两组HR与SV分布曲线明显不同,心衰组HR与SV分布曲线出现分离现象,HR下降而SV上升,呈负相关(P<0.01),而同时段的对照组HR与SV则仍呈正相关(P<0.01).结论 重度充血性心力衰竭患者HR和SV分布的昼夜节律受损,在凌晨100~400之间,HR与SV分布趋势存在分离现象.  相似文献   
27.
Infusion of 1 μg of carbachol, a potent cholinergic agonist, into the lateral septum of the urethane-anaesthetized rat systematically caused the induction of clear-cut hippocampal theta (θ). However, infusion of an equivalent amount of the drug into the hippocampus, close to the recording electrode, failed to induce θ in 50% of the animals and produced a mixture of θ waves and desynchronized activity, resulting in atypical EEG patterns, in the remaining subjects. Both carbachol EEG effects were blocked by intraseptal infusion of the antimuscarinic agent, atropine. Our data demontrate that muscarinic receptors in the septum are predominent sites for cholinergic agonist-antagonist action capable of generating or suppressing hippocampal θ in the rat. They also indicate that intraseptal cholinergic mechanisms play an important role in the initiation and generation of this rhythm.  相似文献   
28.
Ambulatory blood pressure monitoring was applied in 27 pediatric patients aged 6.3 – 24.3 (median 15.0) years who had been transplanted 1.5 – 8.4 years previously. Daytime values were compared with the mean of 10 concomitant casual blood pressure recordings. At the time of the study, antihypertensive drugs were given to 17 patients. Inulin clearance ranged from 18 to 116 (median 66) ml/min per 1.73 m2. Ambulatory blood pressure monitoring confirmed hypertension or normotension determined by casual blood pressure measurements in 63% of patients. The physiological nocturnal dip in blood pressure was attenuated or reversed in 8 of 27 patients. It was reduced in all 3 patients with renal artery stenosis of the graft, in 3 of 4 patients with chronic rejection, in the only patient with recurrent focal segmental glomerulosclerosis, and in 1 of 6 patients with past acute rejection. The dipping was not related to inulin clearance. In conclusion, casual blood pressure measurements do not accurately reflect blood pressure in pediatric patients transplanted more than 1.5 years previously. A reduced nocturnal dip in blood pressure may indicate an underlying renovascular or renoparenchymal pathology. Ambulatory blood pressure monitoring should regularly be applied in patients with renal transplants. Received May 23, 1995; received in revised form June 18, 1996; accepted June 20, 1996  相似文献   
29.
Pacemaker Current if. Since the hyperpolarization-activated current, if, was originally associated with the diastolic depolarization phase of action potential in the sinoatrial (SA) node in 1979, its central role in the generation and control of pacemaker activity has become increasingly clear through a series of experimental findings, some of which have substantially modified the pre-existing theories of cardiac pacemaking and its modulation by the autonomic transmitters. Thus, the pacemaker current of Purkinje fibers, formerly described as a deactivating pure potassium (K) current, was found to be in fact, like the nodal if, inward and activating on hyperpolarization. Furthermore, in SA node cells, as well as mediating rhythm acceleration induced by catecholamines, if was found to underlie the slowing effect of low acetylcholine (ACh) concentrations, in contrast with the generally accepted hypothesis that activation of a K conductance is the main process responsible for cardiac slowing. A final, atypical property of if recently demonstrated concerns the activating action exerted on if by intracellular cAMP. Unlike that on other voltage-gated, cAMP-modulated cardiac channels, this action is independent of phosphorylation and involves a direct binding of cAMP to if channels. (J Cardiovasc Electrophysiol, Vol. 3, pp. 334–344, August 1992)  相似文献   
30.
A 2-year-old boy with known sickle cell disease presented in acute coma. CT revealed bilateral thalamic infarcts and incomplete sinus thrombosis. Angiography confirmed thrombosis of the straight sinus and vein of Galen.  相似文献   
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