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131.

Background

Lipoprotein(a) [Lp(a)] is a lipoprotein in which apolipoproteinB-100 is linked to apolipoprotein(a) [apo(a)]. Significant variation in Lp(a) concentration is specific to LPA gene, which codes for apo(a). Nicotinic acid (NA) is used for treatment of dyslipidemias, and the lowering effect of NA on Lp(a) has been previously reported.

Objective

To evaluate the Lp(a) lowering effect of 1 g/20 mg and 2 g/40 mg day of Nicotinic acid/Laropiprant in subjects with different baseline Lp(a) concentrations and depending on the LPA genotype.

Methods

In an open-label, 10-week study, 1 g/20 mg day of NA/Laropiprant for 4 weeks followed by 6 weeks of 2 g/40 mg day conducted at 3 centers in Spain, 82 subjects were enrolled. Patients were studied at baseline and at the end of both treatment periods and were enrolled in three groups: normal Lp(a) (< 50 mg/dL), high Lp(a) (50–120 mg/dL) and very high Lp(a) (> 120 mg/dL). The LPA genetic polymorphism was analyzed by a real-time PCR.

Results

There was a significant difference in LPA genotypes among Lp(a) concentration groups and an inverse and significant correlation between baseline Lp(a) concentration and LPA genotype was found (R = − 0.372, p < 0.001). There were a significant decrease in total cholesterol, triglycerides, LDL cholesterol, apo B and Lp(a), and a significant increase in HDL cholesterol after NA/Laropiprant treatment, without changes in BMI. However, there were no statistical differences in percentage variation of analyzed variables depending on LPA genotype.

Conclusion

LPA genotype is a major determinant of Lp(a) baseline concentration. However, the lipid lowering effect of NA is not related to LPA genotype.  相似文献   
132.

Objective

Metabolic syndrome (MetS) is associated with cardiovascular disease (CVD). Insulin resistance has been hypothesized as the underlying feature of MetS. Angiotensin converting enzyme inhibitors (ACEI) and angiotensin receptor blockers (ARB) are widely used antihypertensives that may improve insulin sensitivity. The aim of the study is to evaluate the effect of ACEI/ARB on incident CVD events in older hypertensive patients with MetS.

Materials/Methods

We used the Cardiovascular Health Study, a prospective cohort study of individuals > 65 years of age to evaluate ACEI/ARB use and time to CVD events (including coronary and cerebrovascular events). The study included 777 subjects who had hypertension and ATP III-defined MetS, but free of CVD and diabetes at baseline. Cox regression models were used to evaluate the effect of ACEI/ARB as compared to other antihypertensives on the time to the first CVD events.

Results

ACEI/ARB use was associated with a decreased risk of CVD events (adjusted HR = 0.658, 95 % C.I. [0.436–0.993]) compared to other antihypertensives. When CVD endpoints were evaluated separately, use of ACEI/ARB was associated with lower rates of angioplasty and coronary events (HR of 0.129 and 0.530 respectively, with 95 % CI [0.017–0.952] and [0.321–0.875]).

Conclusions

ACEI/ARB use was associated with a lower risk of CVD events in older hypertensive patients with MetS, primarily due to a reduction in coronary events. The potential protective effect of ACEI/ARB on CVD events in older individuals with MetS will need further confirmation from prospective studies.  相似文献   
133.
Background and aimsDehydroepiandrosterone (DHEA) supplementation has gained attention in individuals with adrenal insufficiency, and as a tool for increasing androgens and estrogens whereby is proposed to improve the accretion of muscle and bone mass. However, DHEA supplementation has demonstrated negative effects on the lipid profile and, thus, we aimed to analyze the body of evidence in this regard.Methods and resultsA systematic review and dose-response meta-analysis of randomized controlled trials (RCTs) was performed employing in Scopus, PubMed/Medline, Web of Science, Embase and Google Scholar, then including relevant articles that addressed the effects of DHEA supplementation on the lipid profile, up to February 2020. Combined findings were generated from 23 eligible articles. Hence, total cholesterol (TC) (weighted mean difference (WMD): −3.5 mg/dl, 95% confidence interval (CI): −8.5 to 1.6)), low-density lipoprotein-cholesterol (LDL-C) (WMD: 0.34 mg/dl, 95% CI: −3 to 3.7) and triglycerides (TG) levels (WMD: −2.85 mg/dl, 95% CI: −9.3 to 3.6) did not alter in DHEA group compared to the control, but HDL-C levels significantly reduced in DHEA group (WMD: −3.1 mg/dl, 95% CI: −4.9 to −1.3). In addition, a significant reduction in HDL-C values was observed in studies comprising women (WMD: −5.1 mg/dl, 95% CI: −7.2 to −3) but not in males (WMD: 0.13 mg/dl, 95% CI: −1.4 to 1.7).ConclusionsOverall, supplementation with DHEA did not change circulating values of TC, LDL-C and TG, whereas it may decrease HDL-C levels. Further long-term RCTs are required to investigate the effects of DHEA particularly on major adverse cardiac events.  相似文献   
134.
By analyzing more next‐generation sequencing data, researchers have affirmed that rare genetic variants are widespread among populations and likely play an important role in complex phenotypes. Recently, a handful of statistical models have been developed to analyze rare variant (RV) association in different study designs. However, due to the scarce occurrence of minor alleles in data, appropriate statistical methods for detecting RV interaction effects are still difficult to develop. We propose a hierarchical Bayesian latent variable collapsing method (BLVCM), which circumvents the obstacles by parameterizing the signals of RVs with latent variables in a Bayesian framework and is parameterized for twin data. The BLVCM can tackle nonassociated variants, allow both protective and deleterious effects, capture SNP‐SNP synergistic effect, provide estimates for the gene level and individual SNP contributions, and can be applied to both independent and various twin designs. We assessed the statistical properties of the BLVCM using simulated data, and found that it achieved better performance in terms of power for interaction effect detection compared to the Granvil and the SKAT. As proof of practical application, the BLVCM was then applied to a twin study analysis of more than 20,000 gene regions to identify significant RVs associated with low‐density lipoprotein cholesterol level. The results show that some of the findings are consistent with previous studies, and we identified some novel gene regions with significant SNP–SNP synergistic effects.  相似文献   
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136.
Oxidative stress plays an important role on liver fibrosis progression in the course of hepatitis C virus (HCV) infection. Myeloperoxidase (MPO) is an enzyme released by neutrophils and macrophages, responsible for generating hypochlorous acid and reactive oxygen species (ROS) that may lead to liver injury in HCV infection. On the other hand, antioxidant enzymes such as manganese superoxide dismutase (SOD) controls ROS-mediated damage. The aim of the present study was to investigate the influence of MPO G-463A and SOD2 Ala16Val polymorphisms in the severity of liver fibrosis in individuals with chronic HCV infection. The present study included 270 patients with chronic HCV recruited from the Gastrohepatology Service of the Oswaldo Cruz University Hospital/Liver Institute of Pernambuco (Recife, Northeastern Brazil). All patients underwent liver biopsy, which was classified according METAVIR score. The SNPs were determined by real-time PCR. After multivariate analysis adjustment, the GG genotype of MPO and the presence of metabolic syndrome were independently associated with fibrosis severity in women (P = 0.025 OR 2.25 CI 1.10–4.59 and P = 0.032 OR 2.32 CI 1.07–5.01, respectively). The presence of the GG genotype seems to be a risk factor for fibrosis severity in women with HCV.  相似文献   
137.

Background

Vaginal atrophy, the thinning and drying of vaginal mucosa, is associated with menopause. The standard estrogen treatment is not suitable for all women.

Objective

To investigate the effects of oral sea buckthorn (SB) oil supplementation on vaginal atrophy.

Method

A total of 116 postmenopausal women experiencing symptoms of vaginal dryness, itching or burning were randomized to this placebo-controlled, double-blind study. Ninety-eight participants completed the intervention of three months, during which they consumed 3 g of SB or placebo oil daily. At the beginning and end, factors of vaginal health were scored by a gynecologist, vaginal pH and moisture were measured and vaginal health index was calculated. Symptoms of atrophy and menopause were evaluated at study visits and by daily logbooks. Serum samples were collected for the analysis of circulating lipids, liver enzymes and C-reactive protein.

Results

Compared to placebo, there was a significantly better rate of improvement in the integrity of vaginal epithelium in the SB group when both compliant and noncompliant participants were included (odds ratio (OR) = 3.1, 95% CI 1.11–8.95). A beneficial trend was observed when only the compliant participants were included (OR = 2.9; 95% CI 0.99–8.35). There was a tendency (P = 0.08) toward better improvement of vaginal health index from baseline to the end in the SB group [(0.8 (SD 2.8)] compared to placebo [−0.1 (SD 2.0)].

Conclusions

SB oil showed beneficial effects on vaginal health, indicating it is a potential alternative for mucosal integrity for those women not able to use estrogen treatment for vaginal atrophy.  相似文献   
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