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41.
The presence of tetracycline resistance (Tc(r)) genes and class I integrons (in-1), and their ability to cotransfer were investigated in Tc(r) gram-negative (185 strains) and gram-positive (72 strains) bacteria from Danish farmland and pigsties. The isolates belonged to the groups or species Escherichia coli, Enterobacter spp., Arthrobacter spp., Alcaligenes spp., Pseudomonas spp., and Corynebacterium glutamicum. The 257 isolates were screened for in-1. Eighty-one of the gram-negative isolates were also screened for the Tc(r) genes tet(A), tet(B), and tet(C), and all (n = 72) gram-positive isolates were screened for tet(33). Fourteen (7%) of the soil isolates and eleven (25%) of the pigsty isolates contained in-1. All isolates that contained tet genes also contained in-1, except one gram-negative isolate from a pigsty that contained tet(B). All gram-positive isolates with in-1 also contained tet(33). No isolates contained more than one tet gene. The in-1-positive isolates were tested for resistance to selected antimicrobial agents and showed resistance to three to nine drugs. Filter-mating experiments showed cotransfer of Tc(r) and class I integrons from soil isolates to Escherichia coli and/or Pseudomonas putida. We conclude that soil bacteria in close contact to manure or pigsty environment may thus have an important role in horizontal spread of resistance. Use of tetracyclines in food animal production may increase not only Tc(r) but also multidrug resistance (caused by the presence tet genes and in-1) in bacteria.  相似文献   
42.
Concomitant with the rapid loss of tropical mature forests, the relative abundance of secondary forests is increasing steadily and the latter are therefore of growing interest for conservation. We analysed species richness of fruit-feeding nymphalid butterflies in secondary forest fragments of different age and isolation and in mature forest at the eastern margin of the Lore Lindu National Park in Central Sulawesi, Indonesia. From April to August 2001 we collected 2322 individuals of fruit-feeding butterflies, belonging to 33 species. Butterfly species richness increased with succession, but was significantly higher in mature forests than in all types of secondary forest. Isolation of the forest fragments did not have a significant effect on butterfly species richness in the range of distances (up to 1700 m) studied. Rather it appeared to affect only a few species. Species richness of endemic species was higher than of non-endemic species. Although endemic species were most diverse in mature forests, many species captured were restricted to secondary forests. Our results show that mature forest is essential for the conservation of nymphalid butterflies and for the endemic species in this area. However, considering the relatively large number of species found in these rather small habitat islands, secondary forest fragments, especially older successional stages, can be taken into account in conservation efforts and thus contribute to the preservation of tropical biodiversity on a landscape scale.  相似文献   
43.
The construction of a DNA self-assembling system created by four Y-shaped branched oligodeoxynucleotide building blocks has been studied. The assembly was verified by changes in the fluorescence emission spectra and revealed an additive effect in pyrene excimer band formation during DNA self-assembly.  相似文献   
44.
This study aimed to examine how weaning and how dietary zinc and/or copper fed post weaning may affect the electrophysiological response to glucose and to chloride secretagogues in piglet small intestine in vitro. Study 1 included 54 piglets (six litters of nine piglets). One piglet from every litter was killed 1 day before weaning. The remaining 48 piglets were allocated at weaning (28 d) to four dietary zinc treatments and subsequently killed 1-2, 5-6 or 14-15 days after weaning. Study 2 included 48 piglets (six litters of eight piglets) allocated to four dietary treatments, consisting of high or low dietary zinc with or without high dietary copper. All piglets in study 2 were killed 5-7 days after weaning. The in vitro studies in Ussing chambers showed that weaning resulted in increased ileal glucose absorption as well as increased neuroendocrine-regulated (activated by 5-HT) and cAMP-dependent (activated by theophylline) chloride secretion. High zinc supplementation reduced the responses to 5-HT and theophylline. The study did not reveal any influence of copper on these parameters. It is concluded that the positive effect of zinc supplementation on diarrhoea in weaned piglets may be due to zinc reducing the intestinal mucosal susceptibility to secretagogues that activate chloride secretion.  相似文献   
45.
BackgroundAccording to current recommendations, blood samples should be taken in the morning after 15 minutes’ resting time. Some components exhibit diurnal variation and in response to pressures to expand opening hours and reduce waiting time, the aims of this study were to investigate the impact of resting time prior to blood sampling and diurnal variation on biochemical components, including albumin, thyrotropin (TSH), total calcium and sodium in plasma.MethodsAll patients referred to an outpatient clinic for blood sampling were included in the period Nov 2011 until June 2014 (opening hours: 7am–3pm). Each patient’s arrival time and time of blood sampling were registered. The impact of resting time and the time of day for all components was analysed using simple linear regression. The “maximum allowable bias” was used as quality indicator for the change in reference interval.ResultsSignificant diurnal variation was found for albumin (n = 15,544; p<2×10−16), TSH (n = 20,019; p<2×10−16), calcium (n = 13,588; p = 2.8×10−12) and sodium (n = 51,917; p<2×10−16). Further significant influence for resting time was found for albumin (p = 2.6×10−4), TSH (p = 0.004), calcium (p = 8.9×10−7) and sodium (p = 8.7×10−16). Only TSH and albumin were clinically significantly influenced by diurnal variation. Resting time had no clinically significant effect.ConclusionsWe found no need for resting 15 minutes prior to blood sampling. However, diurnal variation was found to have a significant and considerable impact on TSH and, to a minor degree, albumin. This has to be taken into account to ensure that reference intervals provided by the laboratory are valid on a 24-hour basis.  相似文献   
46.
Chronic obstructive lung disease (COPD) is a common cause of death in industrialized countries often induced by exposure to tobacco smoke. A substantial number of patients with COPD also suffer from pulmonary hypertension that may be caused by hypoxia or other hypoxia-independent stimuli - inducing pulmonary vascular remodeling. The Ca2+ binding protein, S100A4 is known to play a role in non-COPD-driven vascular remodeling of intrapulmonary arteries. Therefore, we have investigated the potential involvement of S100A4 in COPD induced vascular remodeling. Lung tissue was obtained from explanted lungs of five COPD patients and five non-transplanted donor lungs. Additionally, mice lungs of a tobacco-smoke-induced lung emphysema model (exposure for 3 and 8 month) and controls were investigated. Real-time RT-PCR analysis of S100A4 and RAGE mRNA was performed from laser-microdissected intrapulmonary arteries. S100A4 immunohistochemistry was semi-quantitatively evaluated. Mobility shift assay and siRNA knock-down were used to prove hypoxia responsive elements (HRE) and HIF binding within the S100A4 promoter. Laser-microdissection in combination with real-time PCR analysis revealed higher expression of S100A4 mRNA in intrapulmonary arteries of COPD patients compared to donors. These findings were mirrored by semi-quantitative analysis of S100A4 immunostaining. Analogous to human lungs, in mice with tobacco-smoke-induced emphysema an up-regulation of S100A4 mRNA and protein was observed in intrapulmonary arteries. Putative HREs could be identified in the promoter region of the human S100A4 gene and their functionality was confirmed by mobility shift assay. Knock-down of HIF1/2 by siRNA attenuated hypoxia-dependent increase in S100A4 mRNA levels in human primary pulmonary artery smooth muscle cells. Interestingly, RAGE mRNA expression was enhanced in pulmonary arteries of tobacco-smoke exposed mice but not in pulmonary arteries of COPD patients. As enhanced S100A4 expression was observed in remodeled intrapulmonary arteries of COPD patients, targeting S100A4 could serve as potential therapeutic option for prevention of vascular remodeling in COPD patients.  相似文献   
47.
48.
doi: 10.1111/j.1741‐2358.2012.00646.x Perspectives on providing good access to dental services for elderly people: patient selection, dentists’ responsibility and budget management Objectives: To suggest a model for organizing and financing dental services for elderly people so that they have good access to services. Background: There are few studies on how dental services for elderly people should be organized and financed. This is surprising if we take into consideration the fact that the proportion of elderly people is growing faster than any other group in the population, and that elderly people have more dental diseases and poorer access to dental services than the rest of the adult population. In several countries, dental services are characterized by private providers who often operate in a market with competition and free price‐setting. Private dentists have no community responsibility, and they are free to choose which patients they treat. Material and methods: Literature review and critical reasoning. Results: In order to avoid patient selection, a patient list system for elderly people is recommended, with per capita remuneration for the patients that the dentist is given responsibility for. The patient list system means that the dentist assumes responsibility for a well‐defined list of elderly people. Conclusion: Our model will lead to greater security in the dentist/patient relationship, and patients with great treatment needs will be ensured access to dental services.  相似文献   
49.
ABSTRACT

There is growing evidence for combined chronotherapeutic interventions as adjunctive treatments for major depression. However, as the treatments can be demanding, we need to identify predictors of response. This study aimed to describe predictors of response, remission and deterioration in the short-term phase, as well as predictors of long-term response. The predictors investigated were gender, type of depression, severity of depression, treatment resistance, quetiapine use, general self-efficacy, educational level and positive diurnal variation. Follow-up data from 27 inpatients with moderate-to-severe depression participating in a chronotherapeutic intervention were analysed. As a supplement to standard treatment, they completed 3 wake therapy sessions in the first week, 30 min daily light treatment and sleep-time stabilisation in the entire 9-week study period. Patients had a significant decrease of depressive symptoms during the first 6 days measured by HAM-D6. At Day 6, 41% of the patients responded to the treatment and 19% fulfilled the criteria of remission. Deterioration by the end of wake therapy sessions was however not uncommon. In the short-term phase, mild degree of treatment resistance was associated with remission and low educational level associated with deterioration. Positive diurnal variation (mood best in the evening) was a predictor of both short-term and long-term response to combined wake and light therapy. Furthermore, patients with evening chronotypes (measured with morningness-eveningness score) were more responsive. Our results suggest that targeting the combined chronotherapeutic intervention at patients with positive diurnal variation and evening types is a viable option.  相似文献   
50.
Studies in Xenopus laevis suggested that cell-extracellular matrix (ECM) interactions regulate the development of the left–right axis of asymmetry; however, the identities of ECM components and their receptors important for this process have remained unknown. We discovered that FN is required for the establishment of the asymmetric gene expression pattern in early mouse embryos by regulating morphogenesis of the node, while cellular fates of the nodal cells, canonical Wnt and Shh signaling within the node were not perturbed by the absence of FN. FN is also required for the expression of Lefty 1/2 and activation of SMADs 2 and 3 at the floor plate, while cell fate specification of the notochord and the floor plate, as well as signaling within and between these two embryonic organizing centers remained intact in FN-null mutants. Furthermore, our experiments indicate that a major cell surface receptor for FN, integrin α5β1, is also required for the development of the left–right asymmetry, and that this requirement is evolutionarily conserved in fish and mice. Taken together, our studies demonstrate the requisite role for a structural ECM protein and its integrin receptor in the development of the left–right axis of asymmetry in vertebrates.  相似文献   
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