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151.
152.
Jesse Lieberman David Goff Jr Flora Hammond Pamela Schreiner H. James Norton Michael Dulin Xia Zhou Lyn Steffen 《Topics in spinal cord injury rehabilitation》2014,20(2):127-136
Background:
The relationship between cardiovascular disease (CVD) risk factors and dietary intake is unknown among individuals with spinal cord injury (SCI).Objective:
To investigate the relationship between consumption of selected food groups (dairy, whole grains, fruits, vegetables, and meat) and CVD risk factors in individuals with chronic SCI.Methods:
A cross-sectional substudy of individuals with SCI to assess CVD risk factors and dietary intake in comparison with age-, gender-, and race-matched able-bodied individuals enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Dietary history, blood pressure, waist circumference (WC), fasting blood glucose, high-sensitivity C-reactive protein (hs-CRP), lipids, glucose, and insulin data were collected from 100 SCI participants who were 38 to 55 years old with SCI >1 year and compared to 100 matched control participants from the CARDIA study.Results:
Statistically significant differences between SCI and CARDIA participants were identified in WC (39.2 vs 36.2 in.; P < .001) and high-density lipoprotein cholesterol (HDL-C; 39.2 vs 47.5 mg/dL; P < .001). Blood pressure, total cholesterol, triglycerides, glucose, insulin, and hs-CRP were similar between SCI and CARDIA participants. No significant relation between CVD risk factors and selected food groups was seen in the SCI participants.Conclusion:
SCI participants had adverse WC and HDL-C compared to controls. This study did not identify a relationship between consumption of selected food groups and CVD risk factors.Key words: cardiovascular disease risk factors, dietary intake, spinal cord injuryCardiovascular disease (CVD) is a leading cause of death in individuals with chronic spinal cord injuries (SCIs).1–5 This is partly because SCI is associated with several metabolic CVD risk factors, including dyslipidemia,6–10 glucose intolerance,6,11–14 and diabetes.15–17 In addition, persons with SCI exhibit elevated markers of inflammation18,19 and endothelial activation20 that are correlated with higher CVD prevalence.21–23 Obesity, and specifically central obesity, another CVD risk factor,24–26 is also common in this population.12,27–29Dietary patterns with higher amounts of whole grains and fiber have been shown to improve lipid abnormalities,30 glucose intolerance, diabetes mellitus,31–34 hypertension,35 and markers of inflammation36 in the general population. These dietary patterns are also associated with lower levels of adiposity.31 Ludwig et al reported that the strong inverse associations between dietary fiber and multiple CVD risk factors – excessive weight gain, central adiposity, elevated blood pressure, hypertriglyceridemia, low high-density lipoprotein cholesterol (HDL-C), high low-density lipoprotein cholesterol (LDL-C), and high fibrinogen – were mediated, at least in part, by insulin levels.37 Whole-grain food intake is also inversely associated with fasting insulin, insulin resistance, and the development of type 2 diabetes.32,38,39Studies in the general population have also shown a positive association between the development of metabolic syndrome as well as heart disease and consumption of a Western diet, a diet characterized by high intake of processed and red meat and low intake of fruit, vegetables, whole grains, and dairy.40,41 Red meat, which is high in saturated fat, has been shown to have an association with adverse levels of cholesterol and blood pressure and the development of obesity, metabolic syndrome, and diabetes.40,42,43Numerous studies have shown that individuals with chronic SCI have poor diet quality.44–49 A Canadian study found that only 26.7% of their sample was adherent to the recommendations about the consumption of fruit, vegetables, and grains from the “Eating Well with Canada’s Food Guide.”44 Individuals with chronic SCI have also been found to have low fiber and high fat intakes when their diets were compared to dietary recommendations from the National Cholesterol Education Program,46 the 2000 Dietary Guidelines for Americans,49 and the recommended Dietary Reference Intakes and the Acceptable Macronutrient Distribution Range.47,48However, unlike in the general population, the relationship between dietary intake and obesity and CVD risk factors is unknown in the chronic SCI population. If a dietary pattern consisting of higher intake of whole grains and dietary fiber is favorably associated with obesity and CVD risk factors in individuals with chronic SCI, then trials of increased intake of whole grains and fiber intake could be conducted to document health benefits and inform recommendations. The purpose of this pilot study is to investigate the association between selected food group intake and CVD risk factors in individuals with chronic SCI as compared to age-, gender-, and race-matched able-bodied individuals enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Data will also be used to plan future studies in the relatively understudied field of CVD and nutrition in individuals with SCI. 相似文献153.
154.
Altered peptide ligands induce quantitatively but not qualitatively different intracellular signals in primary thymocytes 总被引:3,自引:0,他引:3
Lesley A. Smyth Owen Williams Russell D. J. Huby Trisha Norton Oreste Acuto Steven C. Ley Dimitris Kioussis 《Proceedings of the National Academy of Sciences of the United States of America》1998,95(14):8193-8198
Interaction of the T cell receptor (TCR) with peptide/major histocompatibility complexes (MHC) in the thymus is of critical importance for developing thymocytes. In a previous study, we described an antagonist peptide that inhibited negative selection of transgenic thymocytes induced by an agonist peptide. In this study we show that this antagonist peptide can induce positive selection of CD8+ thymocytes more efficiently than the agonist or the weak agonist peptides, whereas the opposite is true for their ability to cause negative selection. The intracellular signals induced in thymocytes by such peptides after TCR ligation was examined in CD4+8+ double-positive thymocytes from F5/β2mo/Rag-1o transgenic mice. TCR ligation with either the agonist, weak agonist, or antagonist peptide variants resulted in hyperphosphorylation of CD3ζ, CD3, ZAP-70, Syk, Vav, SLP-76, and pp36–38. The extent of phosphorylation of these intracellular proteins correlated with the efficiency with which the peptide analogs induced apoptosis of immature thymocytes. Unexpectedly, there was no correlation between the upstream TCR signaling pathways analyzed and the capacity of the different peptides to induce positive selection. 相似文献
155.
W L Norton 《Annals of the rheumatic diseases》1984,43(6):810-815
Seventy-three episodes of brucellosis in 55 patients are reported. Twenty-two had a systemic illness, 10 arthritis, 10 spondylitis, and four arthritis and spondylitis. Cultures were positive in 77% of cases where appropriate methods were used. A number of rheumatic syndromes may be mimicked by brucellosis and others may coexist with it. A high index of suspicion should prevail in the evaluation of patients from endemic areas. 相似文献
156.
Ishiguro A; Spirin KS; Shiohara M; Tobler A; Gombart AF; Israel MA; Norton JD; Koeffler HP 《Blood》1996,87(12):5225-5231
157.
Catechol estrogens labeled with 3H at different positions in rings A and B of the steroid were synthesized by chemical or enzymatic methods, and their oxidative transformation by male rat brain microsomes was followed by the transfer of 3H into 3H2O. This reaction was shown to occur more readily with the catechol estrogens than with the parent steroid and was also influenced by the position of the radiolabel. Tritium was displaced less readily from C-1 than from C-2 or C-4 of the aromatic ring. Spermine, which is known to increase cytochrome P-450-mediated hydroxylation reactions, had no effect on the release of 3H from ring A of either estradiol or 2-hydroxyestradiol with rat brain microsomes in contrast to liver. Glutathione and other thiols were able to cause a rapid loss of 3H from labeled catechol estrogens, even in the absence of tissue, but in double label experiments with [4-3H]- and [4-14C]2-hydroxyestradiol, the isotope ratio in the recovered catechol estrogen was unchanged. The results illustrate some of the problems in determining accurately the metabolism of estrogens by measuring 3H2O formation when aromatic hydroxylation is involved and also highlight the possible interaction of the catechol estrogens with cellular nucleophiles such as glutathione. 相似文献
158.
Stephen O. Abrokwah Christine M. Moser Edward C. Norton 《International journal of health care finance and economics》2014,14(4):385-406
Many developing countries have introduced social health insurance programs to help address two of the United Nations’ millennium development goals—reducing infant mortality and improving maternal health outcomes. By making modern health care more accessible and affordable, policymakers hope that more women will seek prenatal care and thereby improve health outcomes. This paper studies how Ghana’s social health insurance program affects prenatal care use and out-of-pocket expenditures, using the two-part model to model prenatal care expenditures. We test whether Ghana’s social health insurance improved prenatal care use, reduced out-of-pocket expenditures, and increased the number of prenatal care visits. District-level differences in the timing of implementation provide exogenous variation in access to health insurance, and therefore strong identification. Those with access to social health insurance have a higher probability of receiving care, a higher number of prenatal care visits, and lower out-of-pocket expenditures conditional on spending on care. 相似文献
159.
160.
Helen E. Gruber PhD Ryan Phillips BS Jane A. Ingram BS H. James Norton PhD Edward N. Hanley Jr MD 《Clinical orthopaedics and related research》2014,472(6):1936-1942