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71.
Optimal care for a subgroup of infants with complicated vascular anomalies requires prenatal diagnosis. Fetal vascular lesions are either vascular tumors or vascular malformations, both of which are often detected on routine ultrasound. Imaging, such as ultrasound and fetal MRI, can be used to examine lesions and provide the data for a differential diagnosis, which may impact the course of care both in utero and postnatally. Prenatal diagnosis provides the opportunity for antenatal intervention, parental counseling, and planning of the mode and location of delivery to optimize postnatal care. Prenatal diagnosis of vascular lesions also serves to alert the physician to the potential for associated syndromes and complications. Any indication of a vascular anomaly should be referred for further examination by an experienced multidisciplinary team of physicians to ensure the window in which evaluation, planning, and treatment can take place is not missed. 相似文献
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Molecular and Physiological Responses to Water Deficit in Drought-Tolerant and Drought-Sensitive Lines of Sunflower : Accumulation of Dehydrin Transcripts Correlates with Tolerance 下载免费PDF全文
Fran?oise Cellier Geneviève Conéjéro Jean-Christophe Breitler Francine Casse 《Plant physiology》1998,116(1):319-328
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Objectives To estimate the therapeutic and adverse effects of addition of inhaled anticholinergics to β2 agonists in acute asthma in children and adolescents.Design Systematic review of randomised controlled trials of children and adolescents taking β2 agonists for acute asthma with or without the addition of inhaled anticholinergics.Main outcome measures Hospital admission, pulmonary function tests, number of nebulised treatments, relapse, and adverse effects.Results Of 37 identified trials, 10 were relevant and six of these were of high quality. The addition of a single dose of anticholinergic to β2 agonist did not reduce hospital admission (relative risk 0.93, 95% confidence interval 0.65 to 1.32). However, significant group differences in lung function supporting the combination treatment were observed 60 minutes (standardised mean difference −0.57, −0.93 to −0.21) and 120 minutes (−0.53, −0.90 to −0.17) after the dose of anticholinergic. In contrast, the addition of multiple doses of anticholinergics to β2 agonists, mainly in children and adolescents with severe exacerbations, reduced the risk of hospital admission by 30% (relative risk 0.72, 0.53 to 0.99). Eleven (95% confidence interval 5 to 250) children would need to be treated to avoid one admission. A parallel improvement in lung function (standardised mean difference −0.66, −0.95 to −0.37) was noted 60 minutes after the last combined inhalation. In the single study where anticholinergics were systematically added to every β2 agonist inhalation, irrespective of asthma severity, no group differences were observed for the few available outcomes. There was no increase in the amount of nausea, vomiting, or tremor in patients treated with anticholinergics.Conclusions Adding multiple doses of anticholinergics to β2 agonists seems safe, improves lung function, and may avoid hospital admission in 1 of 11 such treated patients. Although multiple doses should be preferred to single doses of anticholinergics, the available evidence only supports their use in school aged children and adolescents with severe asthma exacerbation.
Key messages
- The addition of multiple doses of anticholinergics to β2 agonist inhalations seems indicated in the initial management of children and adolescents with severe exacerbations of asthma (⩽55% of predicted FEV1)
- For the larger group of children and adolescents with mild to moderate asthma exacerbations, there is no apparent benefit from adding a dose of anticholinergics to β2 agonists
- Little evidence exists to support the systematic addition of anticholinergics to every β2 agonist inhalation, irrespective of patients’ disease severity
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Bruna Aparecida Souza Machado Gabriele de Abreu Barreto Aline Silva Costa Samantha Serra Costa Rejane Pina Dantas Silva Danielle Figuerêdo da Silva Hugo Neves Brand?o José Luiz Carneiro da Rocha Silmar Baptista Nunes Marcelo Andres Umsza-Guez Francine Ferreira Padilha 《PloS one》2015,10(8)
The aim of this study was to determine the best processing conditions to extract Brazilian green propolis using a supercritical extraction technology. For this purpose, the influence of different parameters was evaluated such as S/F (solvent mass in relation to solute mass), percentage of co-solvent (1 and 2% ethanol), temperature (40 and 50°C) and pressure (250, 350 and 400 bar) using supercritical carbon dioxide. The Global Yield Isotherms (GYIs) were obtained through the evaluation of the yield, and the chemical composition of the extracts was also obtained in relation to the total phenolic compounds, flavonoids, antioxidant activity and 3,5-diprenyl-4-hydroxicinnamic acid (Artepillin C) and acid 4-hydroxycinnamic (p-coumaric acid). The best results were identified at 50°C, 350 bar, 1% ethanol (co-solvent) and S/F of 110. These conditions, a content of 8.93±0.01 and 0.40±0.05 g/100 g of Artepillin C and p-coumaric acid, respectively, were identified indicating the efficiency of the extraction process. Despite of low yield of the process, the extracts obtained had high contents of relevant compounds, proving the viability of the process to obtain green propolis extracts with important biological applications due to the extracts composition. 相似文献
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Michele Carbone Erin G. Flores Mitsuru Emi Todd A. Johnson Tatsuhiko Tsunoda Dusty Behner Harriet Hoffman Mary Hesdorffer Masaki Nasu Andrea Napolitano Amy Powers Michael Minaai Francine Baumann Peter Bryant-Greenwood Olivia Lauk Michaela B. Kirschner Walter Weder Isabelle Opitz Harvey I. Pass Giovanni Gaudino Sandra Pastorino Haining Yang 《PLoS genetics》2015,11(12)
We recently discovered an inherited cancer syndrome caused by BRCA1-Associated Protein 1 (BAP1) germline mutations, with high incidence of mesothelioma, uveal melanoma and other cancers and very high penetrance by age 55. To identify families with the BAP1 cancer syndrome, we screened patients with family histories of multiple mesotheliomas and melanomas and/or multiple cancers. We identified four families that shared an identical BAP1 mutation: they lived across the US and did not appear to be related. By combining family histories, molecular genetics, and genealogical approaches, we uncovered a BAP1 cancer syndrome kindred of ~80,000 descendants with a core of 106 individuals, whose members descend from a couple born in Germany in the early 1700s who immigrated to North America. Their descendants spread throughout the country with mutation carriers affected by multiple malignancies. Our data show that, once a proband is identified, extended analyses of these kindreds, using genomic and genealogical studies to identify the most recent common ancestor, allow investigators to uncover additional branches of the family that may carry BAP1 mutations. Using this knowledge, we have identified new branches of this family carrying BAP1 mutations. We have also implemented early-detection strategies that help identify cancers at early-stage, when they can be cured (melanomas) or are more susceptible to therapy (MM and other malignancies). 相似文献
77.
Dhekra Chaara Anne- Laure Ba?uls Najoua Haouas Lo?c Talignani Patrick Lami Habib Mezhoud Zoubir Harrat Jean-Pierre Dedet Hamouda Babba Francine Pratlong 《PLoS neglected tropical diseases》2015,9(12)
Leishmania (L.) killicki (syn. L. tropica), which causes cutaneous leishmaniasis in Maghreb, was recently described in this region and identified as a subpopulation of L. tropica. The present genetic analysis was conducted to explore the spatio-temporal distribution of L. killicki (syn. L. tropica) and its transmission dynamics. To better understand the evolution of this parasite, its population structure was then compared with that of L. tropica populations from Morocco. In total 198 samples including 85 L. killicki (syn. L. tropica) (from Tunisia, Algeria and Libya) and 113 L. tropica specimens (all from Morocco) were tested. Theses samples were composed of 168 Leishmania strains isolated from human skin lesions, 27 DNA samples from human skin lesion biopsies, two DNA samples from Ctenodactylus gundi bone marrow and one DNA sample from a Phlebotomus sergenti female. The sample was analyzed by using MultiLocus Enzyme Electrophoresis (MLEE) and MultiLocus Microsatellite Typing (MLMT) approaches. Analysis of the MLMT data support the hypothesis that L. killicki (syn. L. tropica) belongs to the L. tropica complex, despite its strong genetic differentiation, and that it emerged from this taxon by a founder effect. Moreover, it revealed a strong structuring in L. killicki (syn. L. tropica) between Tunisia and Algeria and within the different Tunisian regions, suggesting low dispersion of L. killicki (syn. L. tropica) in space and time. Comparison of the L. tropica (exclusively from Morocco) and L. killicki (syn. L. tropica) population structures revealed distinct genetic organizations, reflecting different epidemiological cycles. 相似文献
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A soluble enzyme, extracted from tobacco cell-suspension cultures 24 h after treatment with 100 μM methyl jasmonate, has been shown to synthesize acetovanillone (apocynin) from feruloyl-CoA in the presence of NAD. The enzyme displayed Michaelis-Menten kinetics with apparent Km values of 5.6 μM for feruloyl-CoA and 260 μM for NAD and exhibited very high specificity for its substrates. The increase in acetovanillone synthase activity was followed by an increase in the concentration of both acetovanillone and acetosyringone in the culture medium. No intermediate could be detected when analysing the reaction medium by HPLC during the formation of acetovanillone in cell-free extracts. The apparent molecular mass estimated by gel permeation on an FPLC column was ca. 79 kDa. To our knowledge, this is the first report of an enzymic system catalysing the synthesis of an acetophenone. This work demonstrates that the biosynthesis of acetophenones in tobacco proceeds from hydroxycinnamic acids through a CoA-dependent β-oxidation pathway. Interestingly in methyl jasmonate-treated cells, which synthesize very large amounts of hydroxycinnamoylputrescines, inhibition of the synthesis of these conjugates increased the concentration of acetovanillone and acetosyringone in the culture medium, suggesting that the two metabolic pathways can compete for their common precursors, i.e. hydroxycinnamoyl-CoA thioesters. 相似文献