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41.
Collerton J Kingston A Bond J Davies K Eccles MP Jagger C Kirkwood TB Newton JL 《PloS one》2012,7(3):e33078
Introduction
Falls are common in older people and increase in prevalence with advancing old age. There is limited knowledge about their impact in those aged 85 years and older, the fastest growing age group of the population. We investigated the prevalence and impact of falls, and the overlap between falls, dizziness and blackouts, in a population-based sample of 85 year olds.Methods
Design: Cross-sectional analysis of baseline data from Newcastle 85+ Cohort Study. Setting: Primary care, North-East England. Participants: 816 men and women aged 85 years. Measurements: Structured interview with research nurse. Cost-consequence analysis of fall-related healthcare costs.Results
Over 38% (313/816) of participants had fallen at least once in the previous 12 months and of these: 10.6% (33/312) sustained a fracture, 30.1% (94/312) attended an emergency department, and 12.8% (40/312) were admitted to hospital. Only 37.2% (115/309) of fallers had specifically discussed their falls problem with their general practitioner and only 12.7% (39/308) had seen a falls specialist. The average annual healthcare cost per faller was estimated at £202 (inter-quartile range £174–£231) or US$329 ($284–$377). ‘Worry about falling’ was experienced by 42.0% (128/305) of fallers, ‘loss of confidence’ by 40.0% (122/305), and ‘going out less often’ by 25.9% (79/305); each was significantly more common in women, odds ratios (95% confidence interval) for women: men of 2.63 (1.45–4.55), 4.00 (2.27–7.14), and 2.86 (1.54–5.56) respectively. Dizziness and blackouts were reported by 40.0% (318/796) and 6.4% (52/808) of participants respectively. There was marked overlap in the report of falls, dizziness and blackouts.Conclusions
Falls in 85 year olds are very common, associated with considerable psychological and physical morbidity, and have high impact on healthcare services. Wider use of fall prevention services is needed. Significant expansion in acute and preventative services is required in view of the rapid growth in this age group. 相似文献42.
Delaunay A Bromberg KD Hayashi Y Mirabella M Burch D Kirkwood B Serra C Malicdan MC Mizisin AP Morosetti R Broccolini A Guo LT Jones SN Lira SA Puri PL Shelton GD Ronai Z 《PloS one》2008,3(2):e1609
Growing evidence supports the importance of ubiquitin ligases in the pathogenesis of muscular disorders, although underlying mechanisms remain largely elusive. Here we show that the expression of RNF5 (aka RMA1), an ER-anchored RING finger E3 ligase implicated in muscle organization and in recognition and processing of malfolded proteins, is elevated and mislocalized to cytoplasmic aggregates in biopsies from patients suffering from sporadic-Inclusion Body Myositis (sIBM). Consistent with these findings, an animal model for hereditary IBM (hIBM), but not their control littermates, revealed deregulated expression of RNF5. Further studies for the role of RNF5 in the pathogenesis of s-IBM and more generally in muscle physiology were performed using RNF5 transgenic and KO animals. Transgenic mice carrying inducible expression of RNF5, under control of beta-actin or muscle specific promoter, exhibit an early onset of muscle wasting, muscle degeneration and extensive fiber regeneration. Prolonged expression of RNF5 in the muscle also results in the formation of fibers containing congophilic material, blue-rimmed vacuoles and inclusion bodies. These phenotypes were associated with altered expression and activity of ER chaperones, characteristic of myodegenerative diseases such as s-IBM. Conversely, muscle regeneration and induction of ER stress markers were delayed in RNF5 KO mice subjected to cardiotoxin treatment. While supporting a role for RNF5 Tg mice as model for s-IBM, our study also establishes the importance of RNF5 in muscle physiology and its deregulation in ER stress associated muscular disorders. 相似文献
43.
Cheng J Ou JS Singh H Falck JR Narsimhaswamy D Pritchard KA Schwartzman ML 《American journal of physiology. Heart and circulatory physiology》2008,294(2):H1018-H1026
Nitric oxide (NO), generated from L-arginine by endothelial nitric oxide synthase (eNOS), is a key endothelial-derived factor whose bioavailability is essential to the normal function of the endothelium. Endothelium dysfunction is characterized by loss of NO bioavailability because of either reduced formation or accelerated degradation of NO. We have recently reported that overexpression of vascular cytochrome P-450 (CYP) 4A in rats caused hypertension and endothelial dysfunction driven by increased production of 20-hydroxyeicosatetraenoic acid (20-HETE), a major vasoconstrictor eicosanoid in the microcirculation. To further explore cellular mechanisms underlying CYP4A-20-HETE-driven endothelial dysfunction, the interactions between 20-HETE and the eNOS-NO system were examined in vitro. Addition of 20-HETE to endothelial cells at concentrations as low as 1 nM reduced calcium ionophore-stimulated NO release by 50%. This reduction was associated with a significant increase in superoxide production. The increase in superoxide in response to 20-HETE was prevented by N(G)-nitro-L-arginine methyl ester, suggesting that uncoupled eNOS is a source of this superoxide. The response to 20-HETE was specific in that 19-HETE did not affect NO or superoxide production, and, in fact, the response to 20-HETE could be competitively antagonized by 19(R)-HETE. 20-HETE had no effect on phosphorylation of eNOS protein at serine-1179 or threonine-497 following addition of calcium ionophore; however, 20-HETE inhibited association of eNOS with 90-kDa heat shock protein (HSP90). In vivo, impaired acetylcholine-induced relaxation in arteries overexpressing CYP4A was associated with a marked reduction in the levels of phosphorylated vasodilator-stimulated phosphoprotein, an indicator of bioactive NO, that was reversed by inhibition of 20-HETE synthesis or action. Because association of HSP90 with eNOS is critical for eNOS activation and coupled enzyme activity, inhibition of this association by 20-HETE may underlie the mechanism, at least in part, by which increased CYP4A expression and activity cause endothelial dysfunction. 相似文献
44.
Kimberly M. Sheridan Abigail W. Konopasky Sophie Kirkwood Margaret A. Defeyter 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2016,371(1690)
Research indicates that in experimental settings, young children of 3–7 years old are unlikely to devise a simple tool to solve a problem. This series of exploratory studies done in museums in the US and UK explores how environment and ownership of materials may improve children''s ability and inclination for (i) tool material selection and (ii) innovation. The first study takes place in a children''s museum, an environment where children can use tools and materials freely. We replicated a tool innovation task in this environment and found that while 3–4 year olds showed the predicted low levels of innovation rates, 4–7 year olds showed higher rates of innovation than the younger children and than reported in prior studies. The second study explores the effect of whether the experimental materials are owned by the experimenter or the child on tool selection and innovation. Results showed that 5–6 year olds and 6–7 year olds were more likely to select tool material they owned compared to tool material owned by the experimenter, although ownership had no effect on tool innovation. We argue that learning environments supporting tool exploration and invention and conveying ownership over materials may encourage successful tool innovation at earlier ages. 相似文献
45.
Kenneth Kirkwood 《Ethnic and racial studies》2013,36(3):435-438
Joshua Nkomo, Nkomo: The Story of my Life. London, Methuen, 1984, 270 pp., £9.95. 相似文献
46.
47.
R.N. Kirkwood K. Moller W.C. Smith K.R. Lapwood D.J. Garrick 《Animal reproduction science》1985,9(2):163-171
A study was undertaken to evaluate the effects of using an oral progestagen for synchronisation of parturition in the sow. Multiparous Landrace X Large White sows were fed 20 mg allyl trenbolone daily from day 110 to 115 of gestation then 15 mg on day 116 (Group R; N = 12); untreated sows of similar background served as controls (Group C; N = 9). Blood samples, taken at 8-h intervals from day 110 of gestation to onset of parturition, then every 4 h until parturition was complete, were assayed for plasma levels of progesterone, unconjugated oestrone, cortisol and prolactin. Duration of farrowing, incidence of stillbirths and individual piglet birth weights were recorded. Five Group R sows farrowed during the period of progestagen administration, while for the remaining 7, the mean interval from last progestagen treatment to emergence of first piglet was 31.6 ±5.5 h. Gestation length, duration of parturition, and mean interval between successive births all were longer in Group R than in Group C (116.5 ± 0.34 compared with 115.0 ± 0.52 days, P < 0.01; 9.73 ± 1.98 compared with 3.08 ± 0.70 h, P < 0.01; and 53.4 ± 10.2 compared with 16.2 ± 2.4 min., P < 0.01, respectively). No significant treatment differences were apparent for litter size at birth, proportion stillborn or piglet birth weights. Profile analysis showed that plasma progesterone levels in Group R were lower (P < 0.05) during the 30 h prefarrowing, suggesting a longer mean interval between functional luteolysis and parturition in these animals. In both Groups plasma levels of unconjugated oestrone rose in the prefarrowing period, the levels being higher (P < 0.05) in Group R Peak oestrone levels occurred at the commencement of, and had declined to low levels by the completion of, farrowing. Cortisol levels exhibited a pattern similar to that of oestrone, although peak levels at parturition were lower in Group R (P < 0.01). Plasma prolactin levels in the 24 h prepartum rose faster and reached higher levels (P < 0.05) in Group C than Group R, but the difference was no longer apparent subsequent to first piglet emergence. It is concluded that the use of this progestagen to delay parturition upset the synchronisation of endocrine events at farrowing, resulting in an increased duration of parturition. 相似文献
48.
Periodontal disease (PD) afflicts 46% of Americans with no effective adjunctive therapies available. While most pharmacotherapy for PD targets bacteria, the host immune response is responsible for driving tissue damage and bone loss in severe disease. Herein, we establish that the histone demethylase KDM4B is a potential drug target for the treatment of PD. Immunohistochemical staining of diseased periodontal epithelium revealed an increased abundance of KDM4B that correlates with inflammation. In murine calvarial sections exposed to Aggregatibacter actinomycetemcomitans lipopolysaccharide (Aa-LPS), immunohistochemical staining revealed a significant increase in KDM4B protein expression. The 8-hydroxyquinoline ML324 is known to inhibit the related demethylase KDM4E in vitro, but has not been evaluated against any other targets. Our studies indicate that ML324 also inhibits KDM4B (IC50: 4.9 μM), and decreases the pro-inflammatory cytokine response to an Aa-LPS challenge in vitro. Our results suggest that KDM4B inhibition-induced immunosuppression works indirectly, requiring new protein synthesis. In addition, fluorescence-stained macrophages exhibited a significant decrease in global monomethyl histone 3 lysine 4 (H3K4me) levels following an Aa-LPS challenge that was prevented by KDM4B inhibition, suggesting this effect is produced through KDM1A-mediated demethylation of H3K4. Finally, ML324 inhibition of KDM4B in osteoclast progenitors produced a significant reduction in Aa-LPS-induced osteoclastogenesis. These data link histone methylation with host immune response to bacterial pathogens in PD, and suggest a previously unreported, alternative mechanism for epigenetic control of the host inflammatory environment. As such, KDM4B represents a new therapeutic target for treating hyper-inflammatory diseases that result in bone destruction. 相似文献
49.
Hetherington P; Reynolds T; Marshall G; Kirkwood R 《Journal of experimental botany》1999,50(339):1567-1576
Maize (Zea mays L. var. Bonnie) transformed with a
gene encoding a 5-enolpyruvylshikimate 3-phosphate synthase with altered
sensitivity showed over 100-fold greater resistance to the herbicide
glyphosate (N-[phosphonomethyl]glycine) in comparison
with its non-transformed progenitor (parental control) at the third-leaf
stage. Studies with [14C]-glyphosate at a dosage
lethal to the parental control, but sublethal to the transgenic, revealed
that a maximum of 45-65% of the applied dose was absorbed, with greater
absorption occurring in transgenic plants. Translocation of glyphosate was
closely related to its absorption (r value 0.956) with
approximately 15% more of the applied dose being mobilized in transgenic
plants than the parental controls. Analysis of electronic autoradiograms
along the treated leaf lamina found discrete internal regions of glyphosate
accumulation closely associated with the site of application. These regions
contained lower amounts of glyphosate present in the treated leaf lamina
was almost completely translocated in transgenic plants, while in the
parental controls more remained and the leaf became necrotic. In both types
of maize there was a small accumulation of herbicide in the tip region of
the leaf which was not mobilized. Younger shoot tissues and roots were
major sinks for translocated glyphosate accumulating approximately 25-40%
of the applied dose depending upon treatment. In the parental control,
equal amounts of glyphosate were found distributed between young shoot
tissues and roots; while in transgenic plants, the young shoot tissue
accumulated around three times more glyphosate than the roots. In both
plant types, glyphosate was localized in the meristems and young, actively
growing leaves. Specific glyphosate activity (the amount of glyphosate per
unit dry weight of tissue) in the major sinks of the transgenic declined
towards the end of the treatment period but remained relatively constant in
the parental control. In conclusion, enhancing glyphosate resistance by
genetic transformation influenced the absorption, translocation and
distribution of this herbicide in whole plants.Keywords:
Zea mays, glyphosate
(N-[phosphonomethyl]-glycine), transgenic, absorption,
translocation, source-sink.
相似文献
50.