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121.
Haplogroup R1a1‐M198 is a major clade of Y chromosomal haplogroups which is distributed all across Eurasia. To this date, many efforts have been made to identify large SNP‐based subgroups and migration patterns of this haplogroup. The origin and spread of R1a1 chromosomes in Eurasia has, however, remained unknown due to the lack of downstream SNPs within the R1a1 haplogroup. Since the discovery of R1a1‐M458, this is the first scientific attempt to divide haplogroup R1a1‐M198 into multiple SNP‐based sub‐haplogroups. We have genotyped 217 R1a1‐M198 samples from seven different population groups at M458, as well as the Z280 and Z93 SNPs recently identified from the “1000 Genomes Project”. The two additional binary markers present an effective tool because now more than 98% of the samples analyzed assign to one of the three sub‐haplogroups. R1a1‐M458 and R1a1‐Z280 were typical for the Hungarian population groups, whereas R1a1‐Z93 was typical for Malaysian Indians and the Hungarian Roma. Inner and Central Asia is an overlap zone for the R1a1‐Z280 and R1a1‐Z93 lineages. This pattern implies that an early differentiation zone of R1a1‐M198 conceivably occurred somewhere within the Eurasian Steppes or the Middle East and Caucasus region as they lie between South Asia and Eastern Europe. The detection of the Z93 paternal genetic imprint in the Hungarian Roma gene pool is consistent with South Asian ancestry and amends the view that H1a‐M82 is their only discernible paternal lineage of Indian heritage. © 2012 Wiley Periodicals, Inc.  相似文献   
122.

Purpose

Self-reported data suggest that older adults with dementia are inactive. The purpose of the present study was to objectively assess the physical activity (PA) levels of community-dwelling and institutionalized ambulatory patients with dementia, and to compare with the PA levels of cognitive healthy older adults.

Methods

We used actigraphy to assess the PA levels in institutionalized (n = 83, age: 83.0 ± 7.6, Mini-Mental-State Examination (MMSE): 15.5 ± 6.5) and community-dwelling dementia patients (n = 37, age: 77.3 ± 5.6, MMSE-score: 20.8 ± 4.8), and healthy older adults (n = 26, age: 79.5 ± 5.6, MMSE-score: 28.2 ± 1.6). We characterized PA levels based on the raw data and classified <100 counts/min as sedentary behavior.

Results

Institutionalized dementia patients had the lowest daily PA levels (1.69 ± 1.33 counts/day), spent 72.1% of the day sedentary, and were most active between 8:00 and 9:00 am. Institutionalized vs. community-dwelling dementia patients had 23.5% lower daily PA levels (difference M = 0.52, p = .004) and spent 9.3% longer in sedentariness (difference M = 1.47, p = .032). Community-dwelling dementia patients spent 66.0% of the day sedentary and were most active between 9:00 to 10:00 am with a second peak between 14:00 to 15:00. Community-dwelling dementia patients vs healthy older adults’ daily PA levels and sedentary time were 21.6% lower and 8.9% longer, respectively (difference M = 0.61, p = .007; difference M = 1.29, p = .078).

Conclusions

Institutionalized and community-dwelling dementia patients are sedentary for most of the day and the little PA they perform is of lower intensity compared to their healthy peers. Their highest PA peak is when they get out of bed in the morning. In addition, it seems that institutionalized living is associated with lower PA levels in dementia patients. These are the first results that objectively characterize institutionalized as well as community-dwelling dementia patients’ PA levels and confirm that dementia patients are inactive.  相似文献   
123.
124.
The oil of Adenanthera pavonina L. seeds was analysed by chromatographic and instrumental means. The oil was found to be rich in neutral lipids (86.2%), and low in polar lipids (13.8%). The neutral lipids consisted mainly of triacylglycerols (64.2%). Unsaturated fatty acids were found as high as 71%, while the percentage of saturated fatty acids was only 29%. GC and GC/MS analyses revealed linoleic, oleic and lignocerotic acid to be predominant among all fatty acids in the A. pavonina oil, whereas stigmasterol was the major steroid identified within this study. Subsequently, the oil was used for preparation of submicron oil-in-water (o/w) lipid emulsions. Lipid emulsions were formulated by using soybean lecithin (SL) to investigate their particle size, Zeta potential and stability at the different oil and SL ratios. The results obtained indicate possible applications of the tested oil in pharmaceutical and medical fields as drug and cosmetic active ingredient carriers.  相似文献   
125.
GPR81 is an orphan G protein-coupled receptor (GPCR) that has a high degree of homology to the nicotinic acid receptor GPR109A. GPR81 expression is highly enriched and specific in adipocytes. However, the function and signaling properties of GPR81 are unknown because of the lack of natural or synthetic ligands. Using chimeric G proteins that convert Gi-coupled receptors to Gq-mediated inositol phosphate (IP) accumulation, we show that GPR81 can constitutively increase IP accumulation in HEK293 cells and suggest that GPR81 couples to the Gi signaling pathway. We also constructed a chimeric receptor that expresses the extracellular domains of cysteinyl leukotriene 2 receptor (CysLT2R) and the intracellular domains of GPR81. We show that the CysLT2R ligand, leukotriene D(4) (LTD4), is able to activate this chimeric receptor through activation of the Gi pathway. In addition, LTD4 is able to inhibit lipolysis in adipocytes expressing this chimeric receptor. These results suggest that GPR81 couples to the Gi signaling pathway and that activation of the receptor may regulate adipocyte function and metabolism. Hence, targeting GPR81 may lead to the development of a novel and effective therapy for dyslipidemia and a better side effect profile than nicotinic acid.  相似文献   
126.
We examined how the sample representativeness of a single assemblage and the separation of two assemblages can be improved by finding appropriate combinations of sampling effort, taxonomical resolution and abundance weight for stream dwelling caddisflies as model organisms. We found that these parameters strongly influenced the outcome of multivariate analyses both individually and when considered jointly. This is the first study to show that sample representativeness of an assemblage can decrease with increasing sampling effort. We assume that the turnover rate of the assemblage and the rarity of the species are responsible for this phenomenon. We found that the separation of two assemblages can be improved by increasing sampling effort and applying abundance data. Further, we observed that the effect of taxonomical resolution on the separation of ecological assemblages was highly context-dependent. Decreased taxonomical resolution, i.e. changing from species to genus or to family, did not decrease, or even more increased the separation of assemblages. In sum, this study demonstrates the importance of the careful selection of sampling, laboratory and data processing related factors (i.e. sampling effort, taxonomical resolution, abundance weight) in the multivariate comparison of assemblages.  相似文献   
127.
RNA silencing is an evolutionarily conserved system that functions as an antiviral mechanism in higher plants and insects. To counteract RNA silencing, viruses express silencing suppressors that interfere with both siRNA- and microRNA-guided silencing pathways. We used comparative in vitro and in vivo approaches to analyse the molecular mechanism of suppression by three well-studied silencing suppressors. We found that silencing suppressors p19, p21 and HC-Pro each inhibit the intermediate step of RNA silencing via binding to siRNAs, although the molecular features required for duplex siRNA binding differ among the three proteins. None of the suppressors affected the activity of preassembled RISC complexes. In contrast, each suppressor uniformly inhibited the siRNA-initiated RISC assembly pathway by preventing RNA silencing initiator complex formation.  相似文献   
128.
Lipid-protein interactions in membranes are dynamic, and consequently are well studied by magnetic resonance spectroscopy. More recently, lipids associated with integral membrane proteins have been resolved in crystals by X-ray diffraction, mostly at cryogenic temperatures. The conformation and chain ordering of lipids in crystals of integral proteins are reviewed here and are compared and contrasted with results from magnetic resonance and with the crystal structures of phospholipid bilayers. Various aspects of spin-label magnetic resonance studies on lipid interactions with single integral proteins are also reviewed: specificity for phosphatidylcholine, competition with local anaesthetics, oligomer formation of single transmembrane helices, and protein-linked lipid chains. Finally, the interactions between integral proteins and peripheral or lipid-linked proteins, as reflected by the lipid-protein interactions in double reconstitutions, are considered.  相似文献   
129.
The review assesses current status and attempts to forecast trends in the development of lectin biorecognition technology. The progressive trend is characterized scientometrically and reflects the current transient situation, when standard low-throughput lectin-based techniques are being replaced by a novel microarray-based techniques offering high-throughput of detection. The technology is still in its infancy (validation phase), but already shows promise as an efficient tool to decipher the enormous complexity of the glycocode that influences physiological status of the cell. Further enhancement in robustness and flexibility of lectin microarrays is predicted by using recombinant and artificial lectins that will render production of lectin microarrays cost-effective and more affordable. Mass spectrometry is expected to play an important role to characterize the binding profile of new lectins. Differences in glycan recognition by lectins and anti-carbohydrate antibodies are given on a molecular basis, and strong and weak points of both biorecognition molecules in diagnosis are briefly discussed.  相似文献   
130.
Microhabitat selection and seasonal activity of the snake-eyed skink, Ablephaus kitaibelii fitzingeri, are compared to the two lacertid lizards (Lacerta viridis and Podarcis muralis) that co-occur in many of its habitats. The food composition of A. k. fitzingeri is also described. Significant differences in microhabitat selection and seasonal activity among the three species were found. The snake-eyed skink was associated with open grasslands, and with a low level of scrub, bare soil and rock cover. The microhabitat preference of L. viridis was quite similar to that of the skink, but with a higher preference for scrub. P. muralis occurred in places with greater rock and bare soil cover, and more scrub than A. k. fitzingeri. Activity of the snake-eyed skink decreased dramatically in summer, probably because of the reduced thermal inertia originating from the extremely small size of this species, but its seasonal activity overlapped with those of the lacertids. Stomach content analysis of the snake-eyed skink suggests that it is a generalist predator of small, mainly flightless arthropod prey. Competition with juvenile lacertids and predation by adult L. viridis are conceivable for the snake-eyed skink.  相似文献   
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