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71.
The sexually dimorphic dynastine centaurus beetle, genus Augosoma (Coleoptera: Scarabeidae), is endemic to tropical Africa where two species are found (A. centaurus and A. hippocrates). These beetles are consumed by rural populations, cause damage in plantations and are targets of insect collectors and traders. We present information on size differences and analyzed intersexual niche divergence and seasonality of A. centaurus in seven study sites in three West African countries (Ivory Coast, Togo and Nigeria). We recorded 711 light-attracted and/or opportunistically encountered individuals, as well as another 97 beetles in standardized transect surveys. In the latter, we found the adult sex ratio was equal, but was significantly skewed towards females in light-attracted and/or opportunistically encountered individuals. In a sample of 298 adult beetles, males were significantly larger than females, with almost no size overlap between sexes. Beetle activity was highly seasonal with most animals observed in November, active from 19:00 h to 24:00 h. Differences in habitat use were not significant between sexes, with most individuals observed in secondary forest. Males were found higher on vegetation than females and beetles of both sexes were found on Pandanus and raffia palms. Beetles were larger in sites with more vegetation cover, and there was a significant effect of tree species on body size of both sexes. Study area or country had no effect on any of the studied parameters. Our study confirms that transect surveys without light trapping can be an effective tool for understanding large-sized tropical beetles of similar ecological characteristics.  相似文献   
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73.

Objective

Tactile explorations with the fingertips provide information regarding the physical properties of surfaces and their relative pleasantness. Previously, we performed an investigation in the active touch domain and linked several surface properties (i.e. frictional force fluctuations and net friction) with their pleasantness levels. The aim of the present study was to investigate physical factors being important for pleasantness perception during passive fingertip stimulation. Specifically we were interested to see whether factors, such as surfaces'' topographies or their frictional characteristics could influence pleasantness. Furthermore, we ascertained how the stimulus pleasantness level was impacted by (i) the normal force of stimulus application (FN) and (ii) the stimulus temperature (TS).

Methods and Results

The right index fingertips of 22 blindfolded participants were stimulated using 27 different stimuli, which varied in average roughness (Ra) and TS. A 4-axis robot moved the stimuli horizontally under participants'' fingertips with three levels of FN. The robot was equipped with force sensors, which recorded the FN and friction force (FT) during stimulation. Participants rated each stimulus according to a three-level pleasantness scale, as very pleasant (scored 0), pleasant (scored 1), or unpleasant (scored 2). These ordinal pleasantness ratings were logarithmically transformed into linear and unidimensional pleasantness measures with the Rasch model. Statistical analyses were conducted to investigate a possible link between the stimulus properties (i.e. Ra, FN, FT, and TS) and their respective pleasantness levels. Only the mean Ra and FT values were negatively correlated with pleasantness. No significant correlation was detected between FN or TS and pleasantness.

Conclusion

Pleasantness perception, resulting from passive fingertip stimulation, seems to be influenced by the surfaces'' average roughness levels and average FT occurring during fingertip stimulation.  相似文献   
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75.
We report the case of a 74-year-old man with Alzheimer's disease (AD) and an extensive ulcerative lesion on the right ear. AD is a neurodegenerative disease with progressive loss of memory and cognitive deterioration. It has been suggested that apoptotic cell injury and eventually cell death is a major contributor to the AD neurodegenerative process. The ulcerative lesion was surgically excised and the histological analysis reported a well-differentiated squamous cell carcinoma. Caspase-3 (CASP3) plays an important role in neuronal death during nervous system development and under certain pathological conditions. Furthermore, in vitro and in vivo studies reported elevated expression and activation of CASP3 in models of AD. Molecular epidemiological studies suggest that CASP3 may contribute to head and neck squamous cell carcinoma susceptibility and disease progression and that increased CASP3 expression is associated with tumors of the head. Also poly (ADP-ribose) polymerase 1 (PARP1) and the leucine zipper downregulated in cancer 1 (LDOC1) genes play a proapoptotic role. We therefore evaluated the differential expression of LDOC1, PARP1, and CASP3 mRNA in peripheral blood leukocytes of our patient. We found increased expression of all these genes compared with the expression in control subjects.  相似文献   
76.
ABSTRACT: This paper pays attention to the modifiable lifestyle factors such as diet and nutrition that might influence life extension and successful ageing. Previous data reported that in Sicily, the biggest Mediterranean island, there are some places where there is a high frequency of male centenarians with respect to the Italian average. The present data show that in Sicani Mountain zone there are more centenarians with respect to the Italian average. In fact, in five villages of Sicani Mountains, there were 19 people with an age range of 100-107?years old from a total population of 18,328 inhabitants. So, the centenarian number was 4.32-fold higher than the national average (10.37 vs. 2.4/10,000); the female/male ratio was 1.1:1 in the study area, while the national ratio is 4.54:1. Unequivocally, their nutritional assessment showed a high adherence to the Mediterranean nutritional profile with low glycemic index food consumed. To reach successful ageing it is advisable to follow a diet with low quantity of saturated fat and high amount of fruits and vegetables rich in phytochemicals.  相似文献   
77.
The cherry rootstock 'Colt' line was transformed with a phytochrome A rice gene with the aim of altering light perception. Three transgenic events were chosen because of a modified developmental behavior. When red enriched light was supplied horizontally to stems, the PD3 transgenic line showed an increased rate of phytomer formation associated to a superior rate of plant growth compared to wild type (WT). Under the same light conditions, the PO1 and PA lines were less altered in morphology and development. When far-red enriched light was supplied, all transgenic lines had a reduced rate of growth, with the PD3 line being the most similar to the WT. The influence of the alien gene on root and leaf-associated bacteria was studied for a duration of 1 year. Significantly more culturable bacteria were recovered from PA lines than from PO1, PD3 and WT lines. On average, significantly more fluorescent pseudomonads were recovered from the rhizosphere of PA and PO1 lines than from PD3 and WT. No significant differences were detected in the number of bacteria recovered from the phyllosphere of transgenic and WT plant lines. A total of 143 Pseudomonas fluorescens strains isolated from rhizosphere of transgenic and WT lines were tested for their antagonistic activity against Phytophthora nicotianae and differences between bacteria derived from transgenic and WT were not detected. Fluorescent pseudomonads strains isolated from phyllosphere of PA and PO1 lines showed antagonistic activity against P. syringae pv. syringae, whereas no difference among the transgenic and WT lines was detected when fluorescent Pseudomonas strains were tested against P. syringae pv. mors-prunorum. Pathogenicity tests were conducted on rooted and micropropagated plants with P. s. pv. syringae and P. s. pv. mors-prunorum: in all assays, the PO1 lines were the most tolerant to P. s. pv. Syringae, and the PO1 and PD3 were tolerant to P. s. pv. mors-prunorum.  相似文献   
78.
The human delta-globin gene (HBD) is one of the beta-like globin genes expressed in adults. In the Mediterranean countries the carriers of delta-thalassemia defects or Hb A2-variants are >1% and about 40/70 known alleles have been found in families with this ethnic origin. The scope of this study was to investigate the variability of the gene and of the chromosomal background in order to highlight the origin and spreading of the delta-globin gene alleles in the Mediterranean area. We carried out the characterization of the delta-globin gene alleles and of RFLP-haplotypes, SNPs and one microsatellite associated with them in 231 carriers originating principally from East Sicily. Seventeen alleles were identified, of which five were new. The chromosomes associated with mutated alleles from unrelated carriers were 158; the allele Hb A2-Yialousa accounted for about 75% of relative frequency, Hb A2-Mitsero for about 8%. The alleles were associated with RFLP 5'-haplotypes "- - - -" or "+ - + +", prevalent in the Mediterranean area, except Hb A2-Mitsero associated with the 5'-haplotype "Benin" "- - - +" and the Hb A2' associated with "+ - - +", both of African origin. Each allele showed linkage with one haplotype with these exceptions. The Hb A2-Yialousa showed heterogeneity of the 5'-haplotype in 2/58 chromosomes; the Hb A2-Mitsero showed SNPs and (A)gamma-microsatellite typical of a "Benin" haplotype found associated with the Hb C and Hb S chromosomes; the Hb A2-Yialousa (14/58 chromosomes), Hb A2-Mitsero, Hb A2-Pylos, Hb A2-Fitzroy showed heterogeneity in the 3'-haplotypes and beta-globin gene SNPs. The Hb A2-Coburg was found associated with the haplotype "+ - + +/+ +" different from that already reported "- - - -/+ -". With the exception of this last allele, the linkage of each mutation with a core of RFLPs or SNPs around or inside the delta-globin locus suggested the unicentric origin of the mutations followed by recurrent recombination events causing the chromosomal background heterogeneity.  相似文献   
79.
On March 19, 2008 a Symposium on Pathophysiology of Ageing and Age-Related diseases was held in Palermo, Italy. Here, the lectures of M. Racchi on History and future perspectives of Alzheimer Biomarkers and of G. Scapagnini on Cellular Stress Response and Brain Ageing are summarized. Alzheimer's disease (AD) is a heterogeneous and progressive neurodegenerative disease, which in Western society mainly accounts for clinica dementia. AD prevention is an important goal of ongoing research. Two objectives must be accomplished to make prevention feasible: i) individuals at high risk of AD need to be identified before the earliest symptoms become evident, by which time extensive neurodegeneration has already occurred and intervention to prevent the disease is likely to be less successful and ii) safe and effective interventions need to be developed that lead to a decrease in expression of this pathology. On the whole, data here reviewed strongly suggest that the measurement of conformationally altered p53 in blood cells has a high ability to discriminate AD cases from normal ageing, Parkinson's disease and other dementias. On the other hand, available data on the involvement of curcumin in restoring cellular homeostasis and rebalancing redox equilibrium, suggest that curcumin might be a useful adjunct in the treatment of neurodegenerative illnesses characterized by inflammation, such as AD.  相似文献   
80.
Several biomarkers of healthy aging have been proposed in recent years, including the epigenetic clocks, based on DNA methylation (DNAm) measures, which are getting increasingly accurate in predicting the individual biological age. The recently developed “next‐generation clock” DNAmGrimAge outperforms “first‐generation clocks” in predicting longevity and the onset of many age‐related pathological conditions and diseases. Additionally, the total number of stochastic epigenetic mutations (SEMs), also known as the epigenetic mutation load (EML), has been proposed as a complementary DNAm‐based biomarker of healthy aging. A fundamental biological property of epigenetic, and in particular DNAm modifications, is the potential reversibility of the effect, raising questions about the possible slowdown of epigenetic aging by modifying one''s lifestyle. Here, we investigated whether improved dietary habits and increased physical activity have favorable effects on aging biomarkers in healthy postmenopausal women. The study sample consists of 219 women from the “Diet, Physical Activity, and Mammography” (DAMA) study: a 24‐month randomized factorial intervention trial with DNAm measured twice, at baseline and the end of the trial. Women who participated in the dietary intervention had a significant slowing of the DNAmGrimAge clock, whereas increasing physical activity led to a significant reduction of SEMs in crucial cancer‐related pathways. Our study provides strong evidence of a causal association between lifestyle modification and slowing down of DNAm aging biomarkers. This randomized trial elucidates the causal relationship between lifestyle and healthy aging‐related epigenetic mechanisms.  相似文献   
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