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1.
In this study, we examined external and "alien" reinforcement (ER and AR. respectively) as a factor in social learning, and studied the combined effects of culture and reinforcement mode. A female (Experiment 1) and a male (Experiment 2) experimenters conducted experimental sessions. Both men and women, who grew up in the same culture as the experimenter, participated and performed the experimental task. A three-way interaction effect of experimenter gender, culture, and reinforcement mode was found on task performance. And the effect was more pronounced for a Japanese experimenter. A female and a male experimenters conducted Experiments 3 and 4, respectively; however participants this time were men and women who grew up in different cultures than the experimenter. Results indicated that the pattern of the subject gender and reinforcement mode interaction effect, when the experimenter was Japanese with American subjects, was exactly opposite to that when the experimenter was American. These experiments showed that AR was as effective for social learning as ER, and that the cultural backgrounds of experimenter and subject influenced AR and ER effectiveness.  相似文献   

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1. Rates of oxygen uptake and of anaerobic glycolysis were estimated in slices from the renal cortex and medulla (a) of adult rats and guinea-pigs, (b) of new-born (1-, 5- and 21-day-old) rats and of guinea-pigs of 1, 12, 21, 24 and 120 hr age.2. In the adult rat, Q(O2) values for the cortex were 12.55 +/- 0.20 (22) and for the medulla: 8.56 +/- 0.17 (22) mul./hr.mg dry weight, while in the new-born rat (24 hr old) they were 10.99 +/- 0.46 (12) and 9.33 +/- 0.18 (9) mul./hr.mg dry weight respectively.3. Values for Q(CO2) (N2) (anaerobic glycolysis) in the 14 hr old new-born rat were in the renal cortex 9.65 +/- 0.35 (5) and in the medulla 7.39 +/- 0.43 (5) mul./hr.mg dry weight; while in the adult they were 2.25 +/- 0.08 (16) and 5.76 +/- 0.14 (16) mul./hr.mg dry weight, respectively.4. In the adult guinea-pig values for Q(CO2) (N2) were of the same order as in the adult rat, though the rate of O(2) uptake was for the cortex 8.12 +/- 0.22 (12) and for the medulla 5.02 +/- 0.23 (11) mul./hr.mg dry weight.5. Though the Q(O2) values in the renal cortex and medulla were smaller in the 1 hr old new-born guinea-pig, they were already increasing in the 12 hr old neonate.6. The results are discussed in the light of enzyme changes occurring during the process of maturation of the nephron as indicated by histochemical observations.  相似文献   

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BACKGROUND: Early childhood fevers appear to protect against later allergies and asthma. What is not known is the time in which fevers exert this effect and whether the degree of temperature increase is important. OBJECTIVE: We sought to examine the relationship between the time and degree of early fevers and later allergies and asthma. METHODS: Eight hundred thirty-five children from southeast Michigan were enrolled at birth. Clinic records from their first 2 years were abstracted for episodes of fever. At age 6 to 7 years, children underwent allergy testing. We examined fevers occurring within 6-month intervals in the first 2 years of life and outcomes at age 6 to 7 years. The primary outcome measures were allergic sensitization, asthma, asthma with allergic sensitization, and asthma without allergic sensitization. RESULTS: In the unadjusted analysis each episode of fever between 7 and 12 months of age was associated with a lower odds of allergic sensitization (odds ratio [OR], 0.71; 95% CI, 0.54-0.93) and asthma with allergic sensitization (OR, 0.43; 95% CI, 0.21-0.90) at age 6 to 7 years. Likewise, every 1 degrees C increase in the maximum temperature between 7 and 12 months was associated with a lower odds of allergic sensitization (OR, 0.77; 95% CI, 0.61-0.96) and asthma with allergic sensitization (OR, 0.62; 95% CI, 0.40-0.94). After adjusting for potential confounders, each episode of fever between 7 and 12 months was associated with a lower likelihood of asthma with allergic sensitization (adjusted OR, 0.33; 95% CI, 0.11-0.94) at age 6 to 7 years. CONCLUSIONS: Both the timing and intensity of childhood fevers appear to be important factors in the development of allergies and asthma.  相似文献   

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OBJECTIVES:

Declines in cognition and mobility are frequently observed in the elderly, and it has been suggested that the appearance of gait disorders in older individuals may constitute a marker of cognitive decline that precedes significant findings in functional performance screening tests. This study sought to evaluate the relationship between functional capacities and gait and balance in an elderly community monitored by the Preventive and Integrated Care Unit of the Hospital Adventista Silvestre in Rio de Janeiro, RJ, Brazil.

METHODS:

Elderly individuals (193 females and 90 males) were submitted to a broad geriatric evaluation, which included the following tests: 1) a performance-oriented mobility assessment (POMA) to evaluate gait; 2) a mini-mental state examination (MMSE); 3) the use of Katz and Lawton scales to assess functional capacity; 4) the application of the geriatric depression scale (GDS); and 5) a mini-nutritional assessment (MNA) scale.

RESULTS:

Reductions in MMSE, Katz and Lawton scores were associated with reductions in POMA scores, and we also observed that significant reductions in POMA scores were present in persons for whom the MMSE and Katz scores did not clearly indicate cognitive dysfunction. We also demonstrated that a decline in the scores obtained with the GDS and MNA scales was associated with a decline in the POMA scores.

CONCLUSIONS:

Considering that significant alterations in the POMA scores were observed prior to the identification of significant alterations in cognitive capacity using either the MMSE or the Katz systems, a prospective study seems warranted to assess the predictive capacity of POMA scores regarding the associated decline in functional capacity.  相似文献   

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对113例男性乳腺发育症进行临床病理分析。同时检测其中30例乳腺组织中雌激素受体和孕激素受体分布情况,结果发现两者阳性率分别为80.0%和83.33%。结合文献讨论了男性乳腺发育症的发生与高血清激素浓度及乳腺组织高受体水平的关系。  相似文献   

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国际韧带和肌腱研讨会(The International Symposium on Ligaments and Tendons,ISI&T)于2000年在美国佛罗里达州奥兰多市首次召开。研讨会的宗旨是引起对韧带和肌腱研究的重视,并为生物工程师、生物学家、临床医师提供一个可以分享、评论、讨论韧带和肌腱最新研究成果的论坛。从2000年起,国际韧带和肌腱研讨会已经开展了15届;每届研讨会上涌现了大量令人振奋的关于当前韧带和肌腱研究热点和未来挑战的讨论。多年来,韧带和肌腱领域内的研究数量大幅增加,研究质量不断提升。为纪念《医用生物力学》杂志创刊30周年,本文总结过去30年里韧带和肌腱研究的主要进展,包括组织力学、力学生物学、损伤与治愈机制、组织修复和再生。  相似文献   

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Circulating monocytes comprise functionally distinct regular (CD14bright+) and mature (CD141low+) cells. Cell surface receptors were determined by three colour flow cytometry in 8 healthy control subjects. Compared to regular monocytes, mature monocytes had lower levels of the high affinity Fcy receptor 1 (CD64), complement receptor 3 (CDllb), CD45RO and higher levels for HLA-DR, LFA-1 (CD11a/CD18), interleukin-2 receptor (CD25), CD45RA and the Fc receptor 3 (CD16). Both regular and mature monocytes were measured before and up to three hours after four different types of exercise (Ex) in endurance trained athletes (n=9-16). Immediately after anaerobic exercise of I min with a maximal lactate concentration (lamax) of I2.3 (SD I.4) mmol · l–1 and exhaustive exercise of 24 (SD 8) min with a maximal lactate concentration (lamax) of 7.4 (SD 2.6) mmol· l–1 mature monocytes increased more than regular monocytes. Exhaustive endurance exercise of 87 (SD 21) min [lamax 3.7 (SD I.0)] led to a similar increase of regular and mature monocytes. 15–33 min after a 100km run regular monocytes increased significantly, whereas mature monocytes decreased. Up to three hours after the end of all exercises mature monocytes fell below pre-exercise values. In conclusion, duration and intensity of exercise alter distinct maturation stages of monocytes differently. It is probable that the avidity of adhesion molecules like LFA-1 to their endothelial ligands is increased to enable the firm attachment to the endothelium.  相似文献   

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目的从国内狂犬病疫苗aG株中克隆狂犬病病毒糖蛋白(GP)基因和核蛋白(NP)基因,应用杆状病毒-昆虫细胞表达系统使其在昆虫细胞中表达。方法从狂犬病病毒感染细胞上清液中提取病毒RNA,应用RT-PCR方法扩增GP基因和NP基因。扩增的基因与转移质粒连接并转化大肠杆菌,得到重组转移质粒。将其与野生杆状病毒(AcMNPV)线性DNA共转染Sf9昆虫细胞,通过有限稀释法筛选含有GP基因和NP基因重组病毒。初步检测了重组蛋白的抗原性。结果用RT-PCR方法扩增得到GP基因和NP基因,通过重组转移后重组病毒感染的细胞经免疫印染实验表明可分别表达GP和NP重组蛋白。重组蛋白的分子量分别为58×103和53×103。用重组病毒感染的细胞免疫小鼠后可诱导动物产生特异性抗体。结论可以应用杆状病毒-昆虫细胞表达系统表达狂犬病病毒GP和NP重组蛋白,为开发基因工程化狂犬病疫苗提供有意义的资料  相似文献   

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Natural silks as important biomaterials have wide applications in scaffolds for tissues, biocompatible coatings and drug delivery, etc. In this paper, we report on the microstructures and mechanical properties of honeybee and silkworm silks. The microstructures and mechanical properties of these natural silks are measured by environment scanning electron microscopy (ESEM), scanning probe microscopy (SPM), tensile tests, and nanoindentation. It is found that the honeybee silk appears as a single fiber with a circular cross-section and has a much finer and smoother texture than the silkworm silk. The honeybee silk exhibits a distinct linear and brittle elastic feature with an elastic modulus of 6.5 GPa and a breaking strain of 3.8%, whereas the silkworm silk possesses a nonlinear and hierarchical failure character with an initial elastic modulus of 8.9 GPa and a breaking strain of 15.7%. Moreover, the nanoindentation measurements show that the honeybee silk exhibits much less anisotropy than the silkworm silk. The ratio of the longitudinal modulus to the transverse modulus of the honeybee silk is 2.0, whereas that of the silkworm silk is 18.9. The different structural and mechanical properties of the honeybee and silkworm silks are likely a result of their specific biological functions.  相似文献   

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