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101.
广泛性焦虑障碍(GAD)是普遍存在于焦虑症患者之中的基础焦虑障碍,担忧是其核心特征。在众多担忧理论之中,Wells的元认知理论是目前最有效地解释GAD的理论。由该理论发展而来的担忧量表对GAD的鉴别及诊断都显示了很好的信度和效度。 相似文献
102.
Medaka fish (Oryzias latipes) were exposed to various doses of X-rays or fast neutrons, and the frequency of micronucleated cells (MNCs) was measured in gills sampled at 12- or 24-hr intervals from 12 to 96 hr after exposure. The resulting time course of MNC frequency was biphasic, with a clear peak 24 hr after exposure, irrespective of the kind of radiation applied and the dose used. The half-life of MNCs induced in the gill tissues by the two exposures fluctuated around 28 hr, with no significant dose-dependent trend for either X-ray- or neutron-exposed fish. As assayed 24 hr after exposure, the MNC frequency increased linearly over the control level with increasing doses of both X-rays and fast neutrons. The relative biological effectiveness (RBE) of fast neutrons to X-rays for MNC induction was estimated to be 4.3 +/- 0.6. This value is close to the RBE value of 5.1 +/- 0.3 reported for fast neutron induction of somatic crossing-over mutations in Drosophila melanogaster that arise from recombination repair of DNA double-strand breaks. These results and other data support our conclusion that the medaka gill cell micronucleus assay is a reliable short-term test for detecting potential inducers of DNA double-strand breaks. 相似文献
103.
以组分的连续性方程为基础 ,建立了药物从多孔骨架聚合物系统中释放的数学模型。在模型中引入相对渗透速度来刻画药物释放过程中不同机理的影响。对药物从多孔骨架聚合物系统中non -Fickian扩散现象进行了研究 ,特别对药物溶出机制控制的恒速释药现象进行了解释。 相似文献
104.
中学生焦虑与其相关影响因素的综合研究 总被引:14,自引:2,他引:14
目的:综合探讨中学生焦虑状况与其相关影响因素的关系。方法:采用中学生焦虑量表、青少年生活事件量表、艾森克人格问卷、中学生父母教养方式量表和应对量表对558名中学生进行问卷调查。结果:(1)中学生整体的焦虑处于轻度水平,52.6%的学生存在不同程度的焦虑问题,男女生在焦虑水平上不存在较为明显的性别差异,年级差异在焦虑水平上表现也不明显。(2)中学生焦虑与生活事件、父母教养方式、人格和应对方式各因子均有十分显著的相关关系,进一步的回归分析结果表明有八个因素对焦虑的预测作用十分明显,具体为不良情绪应对、学习压力、神经质、父放任型教养方式、人际压力、母过分保护和干涉、解决问题和精神质。结论:中学生中存在较为明显的焦虑问题,多个因素对焦虑有预测作用。 相似文献
105.
106.
We studied visual discrimination learning in a group of Nigerian dwarf goats using a computer-based learning device which was integrated in the animals' home pen. We conducted three consecutive learning tasks (T1, T2 and T3), each of which lasted for 13 days. In each task, a different set of four visual stimuli was presented on a computer screen in a four-choice design. Predefined sequences of stimulus combinations were presented in a pseudorandom order. Animals were rewarded with drinking water when they chose the positive stimulus by pressing a button next to it. Noninvasive measurements of goats' heartbeat intervals were carried out on the first and the last 2 days of each learning task. We analysed heart rate (HR) and heart rate variability (HRV) of resting animals to study sustained physiological effects related to general learning challenge rather than acute excitement during an actual learning session. The number of trials to reach the learning criterion was 1000 in T1, when visual stimuli were presented to the goats for the first time, but decreased to 210 in T2 and 240 in T3, respectively. A stable plateau of correct choices between 70% and 80% was reached on Day 10 in T1, on Day 8 in T2 and on Day 6 in T3. We found a significant influence of the task and of the interaction between task and day on learning success. Whereas HR increased throughout T1, this relationship was inverted in T2 and T3, indicating different effects on the HR depending on how familiar goats were with the learning task. We found a significant influence of the task and the interaction between task and time within the task on HRV parameters, indicating changes of vagal activity at the heart. The results suggest that changes in HR related to learning were predominantly caused by a withdrawal of vagal activity at the heart. With regard to nonlinear processes in heartbeat regulation, increased deterministic shares of HRV indicated that the animals did not really relax until the end of T3. Comparing changes of HR and HRV in T3 and in a subsequent postexperiment (PE), we assume a positive effect of such cognitive challenges once the task had been learned by the animals. 相似文献
107.
A Heryudono R J Braun T A Driscoll K L Maki L P Cook P E King-Smith 《Mathematical medicine and biology》2007,24(4):347-377
We consider model problems for the tear film over multiple blink cycles that utilize a single equation for the tear film; the single non-linear partial differential equation that governs the film thickness arises from lubrication theory. The two models that we consider arise from considering the absence of naturally occurring surfactant and the case when the surfactant is strongly affecting the surface tension. The film is considered on a time-varying domain length with specified film thickness and volume flux at each end; only one end of the domain is moving, which is analogous to the upper eyelid moving with each blink. Realistic lid motion from observed blinks is included in the model with end fluxes specified to more closely match the blink cycle than those previously reported. Numerical computations show quantitative agreement with in vivo tear film thickness measurements under partial blink conditions. A transition between periodic and non-periodic solutions has been estimated as a function of closure fraction and this may be a criterion for what is effectively a full blink according to fluid dynamics. 相似文献
108.
M. Jahn B. Zönnchen W. Köpcke R. Hehlmann 《Journal of molecular medicine (Berlin, Germany)》1988,66(5):190-198
Summary 60 patients with essential thrombocythemia (ET) have been retrospectively and prospectively followed from 1974 through 1987. The presenting signs and symptoms and the course of the disease were analyzed and compared to 10 patients with persisting reactive thrombocytosis selected from 6000 patients with reactive thrombocytosis and to 50 patients with other myeloproliferative diseases. 54 ET-patients presented with complications, 46 with thrombembolic, 3 with hemorrhagic problems and 5 with thrombembolic and hemorrhagic problems. In 6 patients ET was detected accidentally. Disturbances of the microcirculation, mainly of the fingers and the toes, were the most frequent symptom. The average maximal platelet count was 1 207 000/µl. The average platelet count at diagnosis was 880 000/µl. 16 patients had an elevation of the serum creatinin at diagnosis, which deteriorated during the course of the disease. Bone marrow examinations were performed in 56 patients, histology in 48 patients, cytology in 29 patienst. In contrast to the clinical diagnosis the histological diagnosis was in 4 cases each polycythemia vera and myeloproliferative syndrome without further specifiction. 12 patients died thus far. The causes of death were thrombembolic complications in 9, acute leukemia in 2 patients, in 1 patient the cause of death is not known. 10 years after diagnosis 61% of the patients are still alive. It appears that ET is a more important risk factor for the disturbances of the micro- and marcrocirculation than has been recognized until now. ET is, if thrombembolic complications are avoided, a disease with a relatively benign course.
Abkürzungsverzeichnis ET essentielle Thromobozythämie - PRT persistierende reaktive Thombozytose - PV Polyzythämia vera - CML chronisch myeloische Leukämie - MF Myelofibrose - CMPE chronische myeloproliferative Erkrankung unklarer Zuordnung - MM megakaryozytäre Myelose - ALP alkalische Leukozytenphosphatase - Hb Hämoglobin Herrn Prof. Dr. N. Zöllner zum 65. Geburtstag gewidmet 相似文献
Abkürzungsverzeichnis ET essentielle Thromobozythämie - PRT persistierende reaktive Thombozytose - PV Polyzythämia vera - CML chronisch myeloische Leukämie - MF Myelofibrose - CMPE chronische myeloproliferative Erkrankung unklarer Zuordnung - MM megakaryozytäre Myelose - ALP alkalische Leukozytenphosphatase - Hb Hämoglobin Herrn Prof. Dr. N. Zöllner zum 65. Geburtstag gewidmet 相似文献
109.
Exercise motivation and adherence in cancer survivors after participation in a randomized controlled trial: An attribution theory perspective 总被引:1,自引:0,他引:1
Courneya KS Friedenreich CM Sela RA Quinney HA Rhodes RE Jones LW 《International journal of behavioral medicine》2004,11(1):8-17
The purpose of this study was to examine postprogram exercise motivation and adherence in cancer survivors who participated
in the Group Psychotherapy and Home-Based Physical Exercise (GROUP-HOPE; Courneya, Friedenreich, Sela, Quinney, & Rhodes,
2002) trial. At the completion of the GROUP-HOPE trial, 46 of 51 (90%) participants in the exercise group completed measures
of attribution theory constructs. A5-week follow-up self-report of exercise wasthen completed by 30 (65%) participants. Correlational
analyses indicated that program exercise, perceived success, expected success, and affective reactions were strong predictors
of postprogram exercise. In multivariate stepwise regression analyses, program exercise and perceived successwere the strongest
predictors of postprogram exercise. Additionally, perceived success was more important than objective success in understanding
the attribution process, and it interacted with personal control to influence expected success and negative affect. Finally,
postprogram quality of life and changes in physical fitness were correlates of perceived success. We concluded that attribution
theory may have utility for understanding postprogram exercise motivation and adherence in cancer survivors. 相似文献
110.
心脏超声诊断数据挖掘尝试--粗糙集理论运用 总被引:2,自引:0,他引:2
本文的目的是要寻找心脏超声实测指标与心脏病变类型的关系,以建立模型,协助临床医生更科学更准确地进行诊断。但超声实测数据函数关系复杂,难以用传统的统计方法进行分析。因此本文采用粗糙集理论挖掘心脏超声实测指标与心脏病变类型的规则。结果把挖掘出的规则应用到心脏超声诊断上,取得了令人满意的效果。 相似文献