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41.

Purpose

MicroRNA-21 (miR-21) is one of the miRNAs that are frequently and highly overexpressed in tumor tissue of colorectal cancer (CRC) patients; however, only a little is known about its functional role in CRC.

Methods

We examined the expression level of miR-21 in 44 paired samples of tumoral and non-tumoral colon tissues diagnosed for CRC using TaqMan real-time PCR method. Furthermore, we used miR-21 inhibitor (anti-miR-21) to transient knockdown of miR-21 in DLD-1 colon cancer cells and examined the effects of miR-21 silencing on viability, apoptosis, chemosensitivity, cell cycle, and migration of DLD1 cells.

Results

The expression levels of miR-21 were significantly increased in CRC tumor tissue (P?<?0.0001). Significant differences in miR-21 levels were observed also between CRC tissues of patients with CRC in different clinical stages: I vs. II (P?=?0.033) and I vs. IV (P?=?0.021). Kaplan–Meier analysis proved that the miR-21 expression levels are correlated to shorter overall survival of CRC patients (P?=?0.0341). MiR-21 silencing in DLD1 cell line had no effect on the cell viability; however, when combined with chemotherapeutics (5-FU, L-OHP, and SN38), it contributed to the decrease of cell viability. Suppression of miR-21 decreased cell migration ability of DLD-1 cells by nearly 30?% (P?=?0.016).

Conclusion

We have confirmed the overexpression of miR-21 in CRC samples and its correlation with advanced disease and shorter overall survival. These findings could be described in part by the fact that CRC cells with increased expression of miR-21 have higher migration ability.  相似文献   
42.
AIM: To investigate whether selected single nucleotide polymorphisms (SNPs) in miR-196a2, miR-27a and miR-146a genes are associated with sporadic colorectal cancer (CRC).METHODS: In order to investigate the effect of these SNPs in CRC, we performed a case-control study of 197 cases of sporadic CRC and 212 cancer-free controls originating from the Central-European Caucasian population using TaqMan Real-Time polymerase chain reaction and allelic discrimination analysis.RESULTS: The genotype and allele frequencies of SNPs were compared between the cases and the controls. None of the performed analysis showed any statistically significant results.CONCLUSION: Our data suggest a lack of association between rs11614913, rs895819 and rs2910164 and colorectal cancer risk in the Central-European Caucasian population, a population with an extremely high incidence of sporadic colorectal cancer.  相似文献   
43.
44.
Objective: To evaluate Ureaplasma species and Mycoplasma hominis DNA in the cervical fluid and their association with microbial invasion of the amniotic cavity (MIAC) and/or histological chorioamnionitis (HCA) in pregnancies complicated by preterm prelabor rupture of membranes (PPROM).

Study design: A prospective study of 68 women with singleton pregnancies complicated by PPROM between 240/7 and 366/7 weeks was conducted. Cervical fluid and amniotic fluid were collected from all women at the time of admission. The Ureaplasma species and Mycoplasma hominis DNA in the cervical fluid were identified using specific real-time PCR.

Results: Ureaplasma species and Mycoplasma hominis DNA were identified in 59% (40/69) of the cervical fluid samples. Women with the presence of Ureaplasma species DNA with and without Mycoplasma hominis DNA in the cervical fluid had a higher rate of MIAC alone [35% (14/40) versus 11% (3/28); p?=?0.02] and a higher rate of the presence of both MIAC and HCA [30% (12/40) versus 4% (1/28); p?=?0.01] than women without Ureaplasma species and Mycoplasma hominis DNA in the cervical fluid.

Conclusions: The presence of Ureaplasma species DNA with and without Mycoplasma hominis DNA in the cervical fluid is associated with a higher risk of MIAC or MIAC and HCA together in pregnancies complicated by PPROM.  相似文献   
45.
Dopaminergic neurotransmission is involved in several brain functions including spatial cognition. In the present study we examine the effects of systemic administration of D1-like receptor antagonist SCH23390 and D2-like receptor antagonist sulpiride on the acquisition of the Morris water maze task. We used visible versus hidden platform versions of the MWM in order to distinguish between the effects of the drugs on the procedural versus cognitive aspects of the task. SCH23390 was found to prolong escape latencies to the visible platform at a higher dose (0.05mg/kg), whilst the lower dose (0.02mg/kg) left both procedural and cognitive functions almost unchanged. SCH23390 was also found to reduce swimming speed. Sulpiride did not affect the visible platform learning at any of three doses studied (30, 60 and 100mg/kg); the highest dose of sulpiride (100mg/kg) impaired place navigation to the hidden platform, without affecting the swim speed. The results of the present study show a difference in the involvement of D1-like and D2-like receptors in the MWM acquisition.  相似文献   
46.
Early worsening of diabetic retinopathy due to sudden glucose normalization is a feared complication of pancreas transplantation; however, its rate or severity has not been studied prospectively. We followed up 43 pancreas and kidney recipients for a composite endpoint comprising new need for laser therapy, newly diagnosed proliferation, macular edema, visual acuity worsening, and blindness over 12 months. Although 37% of patients met this primary endpoint, its severity was rather low. Mean central retinal thickness and proportion of patients with subclinical macular edema increased significantly, with spontaneous resolution in half of them. Visual acuity did not change. There was no significant difference in the absolute glycated hemoglobin (HbA1c) drop, age, and diabetes duration between the patients who met and those who did not meet the primary endpoint, but a higher proportion of patients with worsening had a recent history of laser treatment. Retinopathy remained stable in 62.8% of patients. In 26%, the visual acuity significantly improved. Although retinopathy worsening was documented in more than one‐third of patients, its evolution was not related to the magnitude of metabolic change; rather, it corresponded to the expected natural course of retinopathy. Nonetheless, comprehensive ophthalmologic care should be a substantial component of the recipient management.  相似文献   
47.

Objective

To identify possible predictors of post-cessation weight gain in smoking abstainers.

Patients and methods

A sample of 607 successful abstainers seen at the Centre for Tobacco-Dependent in Prague, Czech Republic, between 2005 and 2010, was included in this analysis. This sample was followed up for 1 year and included 47.9% women (N = 291) with the mean age of 48 years (18–85).

Findings

Post-cessation weight gain occurred in 88.6% of the 607 abstainers. The mean weight gain after one year post-quit was 5.1 kg (95% confidence interval 4.7–5.5 kg). Baseline characteristics associated with increased weight gain included a higher baseline smoking rate (p < 0.001), more severe cigarette dependence (p = 0.003), less physical activity (p = 0.008), and a report of increased appetite on the baseline assessment of withdrawal symptoms (p < 0.001).

Conclusions

Smokers who are more dependent and have minimal physical activity are at increased risk for post-cessation weight gain. For these smokers, incorporating interventions targeting the weight issue into tobacco dependence treatment is recommended. Further research should be done to identify reasons for this important quitting complication.  相似文献   
48.
Introduction: Research studies have been focusing on the prevalence of alcohol use among children and adolescents since the 1990s. There are many individual, family, and social factors that can influence this kind of risk behaviour. The present review is focused on the influence of parenting styles.

Aims: The main aim is to provide a systematic review of studies published from 1995 until 2012 which investigate the relationship between alcohol use among adolescents and parenting styles.

Methods: A systematic search of literature employing the PRISMA method identified and evaluated 16 original studies published in the EBSCO, MEDLINE/PubMed, JSTOR, and ScienceDirect databases. The studies were classified according to their research design, the age group of the respondents, the participation of parents, the effects of parenting styles, and the sociocultural setting of the study.

Findings: The studies were subjected to quantitative evaluation according to their methodological criteria and forms of parenting styles. Qualitative evaluation showed a broader context and complexity of study results. While there is some evidence of the protective effect of an authoritative parenting style, there are many other individual, social, and environmental factors.

Conclusions: There is evidence of a connection between parenting styles and the forms of alcohol use among children and adolescents. Such conclusions should be reflected in national primary prevention strategies and family-based prevention programmes.  相似文献   

49.
Secondary-cast aluminum alloys have increasing industrial applications. Their biggest deficiency is their impurity content, especially Fe, which has low solubility in Al and almost all the content creates intermetallic phases. This work examines the effect of higher Fe content on the microstructure and properties of A356.0 alloy. At the same time, no other possibility existed to affecting the brittleness of the formation of the β phases. The calculation of Fecrit, ratio of Mn/Fe, quantitative and computed tomography analysis of porosity and Fe plate-like phases, measurement of mechanical and fatigue properties, and fractography analysis were performed in this study. The results show that gravity die casting into a sand mold, and the non-usage of Mn addition or heat treatment, do not have a negative effect on increasing the size of the Fe-rich plate-like phases. The longest Fe-rich phases have limited the pore growth and ratios, but their higher thickness led to greater porosity formation. The mechanical and fatigue properties correlate with the Fecrit level and the highest were for the experimental alloy with 0.454 wt.% of Fe. The experimental results confirmed the fact that if the Fe plate-like phases have a length of up to 50 µm, the fatigue properties depend more on the size of porosity. If the length of the Fe needles is more than 50 µm, then the properties are mainly affected by the length of these Fe phases.  相似文献   
50.
A modified one-step process was used to prepare tetracalcium phosphate/monetite/calcium sulfate hemihydrate powder cement mixtures (CAS). The procedure allowed the formation of monetite and calcium sulfate hemihydrate (CSH) in the form of nanoparticles. It was hypothesized that the presence of nanoCSH in small amounts enhances the in vitro bioactivity of CAS cement in relation to osteogenic gene markers in mesenchymal stem cells (MSCs). The CAS powder mixtures with 15 and 5 wt.% CSH were prepared by milling powder tetracalcium phosphate in an ethanolic solution of both orthophosphoric and sulfuric acids. The CAS cements had short setting times (around 5 min). The fast setting of the cement samples after the addition of the liquid component (water solution of NaH2PO4) was due to the partial formation of calcium sulfate dihydrate and hydroxyapatite before soaking in SBF with a small change in the original phase composition in cement powder samples after milling. Nanocrystalline hydroxyapatite biocement was produced by soaking of cement samples after setting in simulated body fluid (SBF). The fast release of calcium ions from CAS5 cement, as well as a small rise in the pH of SBF during soaking, were demonstrated. After soaking in SBF for 7 days, the final product of the cement transformation was nanocrystalline hydroxyapatite. The compressive strength of the cement samples (up to 30 MPa) after soaking in simulated body fluid (SBF) was comparable to that of bone. Real time polymerase chain reaction (RT-PCR) analysis revealed statistically significant higher gene expressions of alkaline phosphatase (ALP), osteonectin (ON) and osteopontin (OP) in cells cultured for 14 days in CAS5 extract compared to CSH-free cement. The addition of a small amount of nanoCSH (5 wt.%) to the tetracalcium phosphate (TTCP)/monetite cement mixture significantly promoted the over expression of osteogenic markers in MSCs. The prepared CAS powder mixture with its enhanced bioactivity can be used for bone defect treatment and has good potential for bone healing.  相似文献   
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