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91.
Alpha-1 antitrypsin (AAT) deficiency and tobacco smoking are confirmed risk factors for Chronic Obstructive Pulmonary Disease. We hypothesized that variable DNA methylation would be associated with smoking and inflammation, as reflected by the level of C-Reactive Protein (CRP) in AAT-deficient subjects. Methylation levels of 1,411 autosomal CpG sites from the Illumina GoldenGate Methylation Cancer Panel I were analyzed in 316 subjects. Associations of five smoking behaviors and CRP levels with individual CpG sites and average methylation levels were assessed using non-parametric testing, linear regression and linear mixed effect models, with and without adjustment for age and gender. Univariate linear regression analysis revealed that methylation levels of 16 CpG sites significantly associated with ever-smoking status. A CpG site in the TGFBI gene was the only site associated with ever-smoking after adjustment for age and gender. No highly significant associations existed between age at smoking initiation, pack-years smoked, duration of smoking, and time since quitting smoking as predictors of individual CpG site methylation levels. However, ever-smoking and younger age at smoking initiation associated with lower methylation level averaged across all sites. DNA methylation at CpG sites in the RUNX3, JAK3 and KRT1 genes associated with CRP levels. The most significantly associated CpG sites with gender and age mapped to the CASP6 and FZD9 genes, respectively. In summary, this study identified multiple potential candidate CpG sites associated with ever-smoking and CRP level in AAT-deficient subjects. Phenotypic variability in Mendelian diseases may be due to epigenetic factors.  相似文献   
92.
In passalids, metamorphosis takes place inside pupal cells which are built by adults piling detritus on the pupa until it is completely covered by a cell. The results reported in this paper show the significance of an olfactory stimulus in the release of this behavior. Adults do not differentiate conspecific pupae originating from their own or other nests for the construction of pupal cells; however, they do not build these cells for heterospecific pupae. It was not possible to demonstrate significant differences between males and females with regard to the presentation of this behavior, but differences were found between young and mature adults. The former require greater stimulation and are less efficient in the construction of cells than the latter. Nevertheless, all adults, including very young ones, can perform the behavior. It was also found that, under laboratory conditions, metamorphosis is normally developed in the absence of pupal cells. Some hypotheses about the possible function of these cells are discussed.  相似文献   
93.
Synopsis Yellowfin shiners spawn in nests constructed by male bluehead chubs. To determine whether yellowfin shiners are obligatory symbionts of bluehead chubs, different densities of shiners were isolated from chubs and presented with artificial nests in stream enclosures. Yellowfin shiners failed to reproduce in the absence of bluehead chubs, indicating that the symbiosis is obligatory for the shiners. Bluehead chubs tended nests by moving stones, which kept the nests free of silt. Nest tending lasted for the same amount of time that embryos and larvae of both species were found in the nests. Yellowfin shiners benefit from a protective nest and parental care given by the chub. Eggs, embryos and larvae of both species may benefit from reduced predation due to a dilution effect. These observations suggest that this nest association is an obligatory, mutualistic symbiosis.  相似文献   
94.
95.
Dieting behaviors in a sample of 183 overweight older adults were studied to assess how they were influenced by six cognitive, behavioral, emotional, and social variables. Membership in a weight control program was also evaluated to assess whether it affected these relationships. Responses indicated that reports of high quality dieting behaviors were associated with higher levels of depression and less effective coping skills. Dieting behaviors among subjects who were participants in weight loss programs were not as strongly associated with less effective coping skills, but were associated with external health locus-of-control. The degree of social support had a limited impact on dieting behaviors, while measures of optimism and health status were unrelated to dieting behaviors. We concluded that older adults, especially those who diet independently, are likely to experience significant stress associated with weight loss efforts. Weight loss programs for older adults might produce better outcomes if they focus on reducing depression and stress associated with dieting.  相似文献   
96.
In this article, the spatial statistic known as the K function is adapted for temporal processes and patterns. The (optimal) K-function estimator is used in a testing procedure to determine whether behavior patterns of exposed rats versus control rats are different. Specifically, the temporal analogue to the K function is given and an approximately optimal estimator is developed. Next, a testing procedure, to determine whether a group of point patterns is generated from complete temporal randomness, is given. Finally, a testing procedure, to compare pairwise two groups of point patterns to each other, is given. The testing procedures are illustrated with rat-behavior data from both a control-control experiment as well as an exposed-control experiment, where in the latter case a difference in behavior is known to exist.  相似文献   
97.
An environmental and sensitive sample pretreatment method was established and combined with high‐performance liquid chromatography (HPLC) for the analysis of tetracycline hydrochloride (TC) in feed water and lake water. One element small molecule alcohol‐salt aqueous two‐phase system (ATPS) cannot effectively adjust the polarity of the system, but binary small molecule alcohol‐salt ATPS can adjust the polarity and improve the extraction efficiency of antibiotics. In this work, a binary ATPS based on ethanol +2‐propanol + (NH4)2SO4 system was formed and applied to the separation and purification of TC in real water samples. The influence factors on partition behaviors of TC were discussed, including the types and the concentration of phase salts, the volume ratio of alcohol, the pH value, extraction temperature, and the standing time. The response surface methodology was used to determine the best experimental conditions for multi‐factor experiments. Under this optimal condition, the extraction efficiency of TC reached 95.7%. This new method is considered to have significant application in the divorce of antibiotics.  相似文献   
98.
Male damselfish typically demonstrate uniparental egg-guarding care in nature. Potential plasticity in sexual behavior has recently been reported in various teleost fish. To examine behavioral plasticity in parental care, we conducted aquarium experiments to explore the potential for egg-guarding care in the female damselfish, Dascyllus reticulatus. After initial caretaking, males were removed from the mating nests, and cohabiting females frequently exhibited egg predation on the same day. However, we confirmed that females showed significantly decreased egg-predation frequencies on the following day and showed egg-caring behaviors. All experimental females guarded their eggs until they hatched. Females subsequently spawned eggs as females even after performing parental care behaviors, indicating no progression of sex change into males. Molecular analysis of select pituitary gland hormones indicated that egg-caring females and males showed high expression levels of prolactin, suggesting its involvement in the development of parental care behaviors. The cryptic possession of caretaking ability in females may be a tactical response to the need for temporary replacement of the care roles in cases where caretaking males are removed, for example, through predation, in damselfish species living in sexually cohabiting groups.  相似文献   
99.
The evolution of group living is generally associated with the emergence of social behaviors that ensure fitness benefits to group members. However, the expression of these behaviors may depend on group composition, which can vary over time with respect to sex, starvation status, and relatedness. Here, we investigated (1) whether adults of the group‐living European earwig, Forficula auricularia, show cooperative behaviors toward conspecifics and (2) whether sex, food availability, and relatedness shape the nature and frequency of these behaviors. We conducted a full‐factorial experiment using 108 unisexual pairs of adults, in which we manipulated these three factors and video‐recorded the earwig behaviors for 45 min. Our results revealed that adults mostly expressed self‐directed and aggressive behaviors. Nevertheless, they also showed allogrooming, a social behavior that offers scope for cooperation. Pairs of males displayed longer bouts of aggression and allogrooming (when it occurred) than pairs of females. Food deprivation had no effect on male behaviors, but females spent less time self‐grooming and walking when they were food deprived. Finally, low relatedness between adults did not influence any of the measured behaviors, but exacerbated frass production, possibly due to social stress. Overall, these results indicate the limited role of cooperation among F. auricularia adults during their group‐living phase.  相似文献   
100.
We analyze weight and fat percentage measurements of respondents in an online general population panel in the Netherlands, collected using wireless scales, with an average frequency of 1.6 measurements per week. First, we document the existence of a weekly cycle; body mass is lowest on Fridays and highest on Mondays, showing significant (p < 0.01) differences of, on average, 0.2 kilogram in weight, 0.06 in BMI value, and 0.03 in fat percentage. Second, we find that in the general population fat-based measures of obesity point at a three times larger prevalence of obesity (53%) than BMI-based measures (17%). Third, we find that feedback that includes a recommended weight range increases the temporal variation in individual body mass by almost ten percent (sd for weight increases from 1.13 to 1.22; sd for BMI increases from 0.37 to 0.41; sd for fat percentage increases from 0.55 to 0.61.  相似文献   
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