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151.
152.

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).15 This is partly because SCI is associated with several metabolic CVD risk factors, including dyslipidemia,610 glucose intolerance,6,1114 and diabetes.1517 In addition, persons with SCI exhibit elevated markers of inflammation18,19 and endothelial activation20 that are correlated with higher CVD prevalence.2123 Obesity, and specifically central obesity, another CVD risk factor,2426 is also common in this population.12,2729Dietary patterns with higher amounts of whole grains and fiber have been shown to improve lipid abnormalities,30 glucose intolerance, diabetes mellitus,3134 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.4449 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.
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.
Brucellosis and rheumatic syndromes in Saudi Arabia.   总被引:1,自引:3,他引:1       下载免费PDF全文
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.
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.
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.

Background

Disc space narrowing, osteophytes, and disc degeneration are common and increase with aging. Few animal models are appropriate for the study of spontaneous age-related cervical disc degeneration.

Questions/purposes

We used the sand rat, a member of the gerbil family with well-recognized age-related lumbar disc degeneration, to determine whether spontaneous cervical disc degeneration differed from lumbar degeneration when evaluated by (1) radiologic and (2) histologic measures. Animals 2 to 25 months of age were used in these analyses.

Methods

Cervical and lumbar discs of 99 sand rats were analyzed with radiology, and cervical discs of 67 sand rats were studied with histology. Lateral digital radiographs of cervical and lumbar spines were scored for presence or absence of wedging, disc space narrowing, osteophytes, end plate calcification, and irregular disc margins at C2-C3 through C6-C7 and T12-L1 through L7-S1. Percentages for presence were calculated and statistically analyzed for younger (range, 2-11.9 months old) versus older (range, 12.0-25 months old) animals.

Results

Cervical discs in younger animals exhibited a greater proportion of irregular margins compared with lumbar sites (94% versus 83%; p = 0.02; 95% CI for difference, 2.7, 19.0%). In older animals, cervical discs showed a greater proportion of osteophytes than did lumbar discs (7% versus 0%; p < 0.0001). The incidence of disc space narrowing was greater in cervical versus lumbar sites (99% versus 90%; p = 0.0008). Cervical spine sites which contained osteophytes morphologically showed irregular disc margins and revealed an extrusion of herniated disc material in the osteophytes.

Conclusions

Radiologic and morphologic studies confirmed age-related disc degeneration in the cervical spine of the sand rat.

Clinical Relevance

Clinical cervical aging studies have shown that 14% of asymptomatic subjects younger than 40 years have abnormal MRI scans with an increase to 50% by 50 years old. We studied an economic rodent model for cervical age-related spontaneous disc.  相似文献   
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