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《Chronobiology international》2013,30(8):1109-1120
A flatter diurnal rhythm of cortisol has been reported to be associated with early mortality in patients with metastatic breast cancer. The clinical stage of disease at the time of diagnosis and the patient's performance status (PS) are known to be important prognostic factors for lung cancer (LC) survival. The authors examined the relationship between diurnal cortisol rhythms and these prognostic factors in patients with advanced LC. Cortisol concentrations were measured in saliva samples collected from 52 patients (37 males/15 females) with advanced LC and from 56 healthy subjects (32 males/24 females) to characterize the diurnal cortisol rhythm, specifically the cortisol awakening response (CAR) and diurnal cortisol decline (DCD). Variations of CAR and DCD in the patients were analyzed according to their clinical disease stage and PS score, and the differences in CAR and DCD between patients and healthy controls were compared. The patient group showed significantly reduced diurnal cortisol secretory activity and rhythmicity, compared with healthy controls. When the patients were subgrouped according to their clinical disease stage, patients with stage 4 disease showed significantly reduced CAR and flatter DCD compared with the healthy controls. However, the CAR and DCD in patients with stage 3a and 3b disease were comparable to those of healthy controls. Neither the CAR nor the DCD showed stepwise changes as the disease stage worsened. When patients were subgrouped according to their Eastern Cooperative Oncology Group (ECOG) PS score, there was stepwise reduction in the CAR and flattening of the DCD as the PS score increased. Both an abolished CAR and a flattened DCD were common in patients with ECOG PS scores of 3 and 4. These results indicate that alteration of the diurnal cortisol rhythm in patients with advanced LC is more closely associated with their PS score than with their clinical disease stage. Gradual alteration of the CAR and DCD, indicative of loss of 24-h cortisol rhythm, in concert with increase in PS score implies that endogenous circadian rhythms may also be disintegrating as the PS score worsens in these patients. (Author correspondence: )  相似文献   

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Characteristics of photoassimilate efflux from the leaves of grapevine (Vitis vinifera L., var. Rkatsiteli) plants under natural conditions and upon darkening, defoliation, and ABA treatment at short exposures (2, 6, and 24 h) as well as diurnal pattern of starch content in the leaves were investigated. Translocation of assimilates from the leaves of grapevine usually occurred at night and started after 20:00 or 21:00. However, such pattern of translocation was not strictly determinated and could be changed upon the action of some factors. Darkening, defoliation, and treatment with ABA initiated the translocation of photoassimilates from the leaves in the daytime. Darkening and ABA treatment turned out to be more efficient than defoliation. Darkening and defoliation significantly changed the character of partitioning of photoassimilates in the stem. We corroborated the opinion that in grapevine, the efflux of assimilates from source leaves is also governed by the feedback mechanism and probably much depends on the level of carbohydrates.  相似文献   

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2011年1~2月,采用焦点动物观察法对鄱阳湖康山湖候鸟自然保护区内越冬小天鹅种群进行了时间分配和日间活动节律的研究。通常认为小天鹅是典型的游禽,冬季大部分时间都在水中游动。我们的研究结果表明,93.2%的个体在湿地洲滩生境内活动。2010年鄱阳湖持续高水位导致的水体生境中食物短缺,可能是迫使小天鹅主要在湿地洲滩生境活动的主要原因。取食是小天鹅越冬期间最主要的行为,占52.6%,其次为警戒18.2%、运动10.6%、休息10.0%和理羽8.6%。取食、警戒、运动、休息和理羽行为发生的持续时间存在显著差异,休息行为持续最长,平均为48.4s±2.9s,警戒行为的持续时间最短,平均持续时间为9.5s±0.6s。小天鹅在水域生境和湿地洲滩生境中时间分配存在显著差异,在水域生境以休息为主,在湿地洲滩生境以取食为主。除理羽行为与休息行为发生节律存在显著的负相关,其他行为没有显著的相关性。  相似文献   

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鄱阳湖越冬鹤鹬的日间行为节律   总被引:1,自引:0,他引:1  
目前有关鸟类越冬行为节律的研究主要集中在大型水鸟。与大型鸟类相比,小型鸟类在体温调节中消耗的能量更多,因此可能呈现不同的日间行为节律。本研究选择鄱阳湖数量较大的小型水鸟——鹤鹬Tringa erythropus为研究对象,于2014年11月—2015年3月在鄱阳湖的子湖——常湖池对越冬期鹤鹬各种行为的时间分配进行了调查研究。结果表明觅食(61.4%)和休息(32.1%)是鹤鹬越冬期最主要的行为,2种行为的比例呈显著负相关。与一些植食性水鸟相比,肉食性鹤鹬的觅食行为比例偏低。而与一些大型食肉性水鸟相比,鹤鹬的觅食行为比例偏高,这可能与其较小的体型在体温调节中消耗的能量较多有关。鹤鹬的警戒行为比例较低(0.8%),越冬期集大群的习性可能是导致其偏低的主要原因。越冬期不同月份间各行为比较中,1月出现了觅食行为比例的高峰和休息行为比例的低谷,这可能与1月平均气温为全年最低有关。觅食行为比例在全天呈缓慢上升趋势,而休息行为比例呈下降趋势。虽然觅食和休息行为的时间分配在全天有一定变化,但是鹤鹬的日间行为节律性并不强。鹤鹬的觅食行为主要发生在跗跖位(0~5.5 cm),而休息行为主要发生在跗跖上位(5.5~8.6 cm),安全性和食物的可利用性可能是影响鹤鹬生境选择的主要因素。  相似文献   

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A hybrid Phalaenopsis plant was grown hydroponically on a nutrientsolution of Hyponex in the greenhouse. Typical daily patternsof CO2 fixation, production of malic acid and citric acid andpH of the leaf and root were determined. The rate of primaryfixation of CO2 in the leaf increased markedly in the evening,remained high until well into the afternoon, then decreasedsharply. The pattern of production of organic acids resultedfrom the fact that the rate of uptake of CO2 gas was highestat night and fell during the day. A high correlation betweenpH value and level of malic acid in the leaves was observed,and an exponential relationship appeared to exist between theseparameters. These rhythmic sequences were not observed in theroot. The results suggest that metabolism in the leaf had characteristicsof CAM (Crassulacean Acid Metabolism), while the root did not. (Received May 6, 1988; Accepted October 25, 1988)  相似文献   

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The osmotic surplus of the guard cells —i.e., the difference between the guard cells’and epidermal cells’omotic value at incipient plasmolysis (Vicia Faba) —exhibits an endogenous diurnal-periodic variation that is synchronous with the endogenous diurnal periodicity in the movements of the guard cells. The osmotic surplus of the guard cells is found to arise and drop by changes not only in these cells, but also in the epidermal cells.  相似文献   

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Peripheral blood plasma Cortisol concentration and its diurnal variation was measured in 4 horses. Mean concentration of Cortisol during 24 hrs. was 42 ng/ml (s ± 20 ng/ml). Peak values occurred at 6 a.m. and the lowest values were observed at about 6 p.m. (mean 65 ng/ml and 20 ng/ml, respectively). Long-acting ACTH at a dose of 150 i.u. was given by intramuscular injection to the 4 horses. Peak Cortisol concentrations markedly exceeding the prestimulation level were obtained between 2 and 4 hrs. after injection. During the immediate 24 hrs. after these peaks, the mean Cortisol level was markedly lower and the cyclic variation out of phase with the basal diurnal pattern. After a gradual adjustment during the second postinjection day, no differences could be seen between the 2 patterns on day 3 after injection.  相似文献   

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2011年1月至11月使用瞬时扫描法及焦点动物取样法对云南省大理市洱源县西湖湿地(26°00′~26°01′N,100°02′~100°03′E,平均海拔1 970 m)的紫水鸡(Porphyrio porphyrio)行为进行了观察,将行为定义为取食、寻食、休息、修饰、警戒、位移和其他共7类,扫描时将取食和寻食合并为觅食,分析非繁殖期的日节律和时间分配特点。觅食高峰出现在早晨和傍晚,低谷在秋季为下午14:30时(占所有行为类型56.56%)、冬季12:30时(55.61%)、春季11:00时(55.80%)。休息高峰秋季出现在12:30时(26.79%),冬季一日内呈上升趋势,春季呈双峰型,低谷在13:30时(14.64%)。从时间分配来看,寻食、取食、修饰等行为在不同季节间存在显著差异,寻食时间从高至低依次为冬季、春季、秋季,分别占总活动时间的19.87%、9.36%、3.03%;取食时间则相反,依次为秋季(72.54%)、春季(56.78%)及冬季(44.59%);与新西兰Pukepuke Lagoon种群相比,西湖湿地紫水鸡种群在秋季大量取食,在冬季增加寻食和休息时间,以应对高原湿地的温度和食物变化。修饰行为在繁殖期前(春季)最多(15.84%),繁殖期后(秋季)减少(11.10%)。以上结果说明,为适应气候、食物等条件的年周期变化,紫水鸡行为策略在不同时期和地点具有可塑性,这可能是该物种在滇西北地区得以繁衍及扩散的原因之一。  相似文献   

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矮岩羊夏季活动节律、时间分配和集群行为   总被引:3,自引:0,他引:3  
采用扫描取样法(每隔10 min进行一次扫描纪录,记录时间为5 min)对36只矮岩羊夏季昼间节律与时间分配进行了观察和研究,将矮岩羊行为划分为取食、移动、站立、卧息和其他行为等5类。结果表明,矮岩羊在夏季有3个取食高峰(6:00-9:00、10:00-11:00和16:00-20:00);1个卧息高峰(11:00-15:00)。在时间分配上,用于取食的时间最多(30.14±3.32)%,其次是卧息(26.44±3.59)%,站立(24.90±4.27)%,移动(15.73±1.26)%,而用于其他行为的时间,仅占(2.82±1.00)%。通过不同个体的比较,发现成年雄性用于取食和站立的时间最多,幼体用于移动和其他行为的时间最多,成年雌性用于卧息的时间最多。在矮岩羊集群方面,其集群类型有:混合群、母仔群、雄性群、雌性群和独羊,在夏季集群平均大小为(7.81±8.42)只,2~8只的羊群,占总群数的54.05%;不同集群类型的大小差异极显著(χ2=13.197,dƒ=3,P=0.004),混合群群体最大,而雄性群最小;雌雄比为1∶0.54,雌幼比为1∶0.26,成幼比为1∶0.17。这些都说明矮岩羊这类独特的行为和种群特征是长期适应金沙江干热河谷的结果。  相似文献   

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青海省都兰县沟里乡幼龄藏狐昼间行为节律   总被引:1,自引:1,他引:1  
2007年3月6日~4月25日,采用焦点取样和瞬时扫描取样相结合的方法对3只幼龄藏狐(Vulpesferrilata)的昼间行为进行观察记录,并分析其节律及组成.结果表明,休息行为是幼龄藏狐日常活动的主要组成部分,其次为捕食行为和嬉戏行为.幼龄藏狐以晨昏活动为主,主要活动时间集中在8:00~9:00时和16:00~19:00时,其余时间以休息为主.成体藏狐出现后,幼龄藏狐嬉戏行为增加,而休息行为减少,并伴随有奔跑和亲昵行为.  相似文献   

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Factor VII has been utilized to treat post-operative bleeding after cardiac surgery refractory to other intervention. We report the case of a patient who developed intractable bleeding after a severe protamine reaction following emergency repair of type A aortic dissection and was successfully treated with factor VII.  相似文献   

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J. A. Graham  A. M. Paton  A. L. Linton 《CMAJ》1971,104(11):1000-1003
Body water and electrolyte contents have been measured by means of muscle biopsy analysis in 11 patients with untreated acute renal failure and in one patient during the diuretic recovery phase of his illness. Patients with acute oliguric renal failure show two main types of imbalance. One group shows evidence of a reduction in extracellular sodium and chloride with normal intracellular water and electrolytes. These findings are thought to be due to a combination of excess urinary salt loss during the development of oliguric renal failure, and inadequate replacement of extrarenal electrolyte losses. A second group shows overhydration of both extra- and intracellular phases, associated with an excess of sodium and chloride. The intracellular potassium concentration is reduced, owing to the intracellular water excess. The patient studied during the diuretic recovery phase of acute renal failure showed a marked loss of sodium and chloride, which emphasizes the necessity to replace urinary electrolyte losses at this stage of the illness. It is often extremely difficult to assess fluid and electrolyte balance in patients presenting with acute renal failure, and muscle biopsy analysis or isotope dilution studies may be required before accurate replacement therapy is possible.  相似文献   

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