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1.

Background

Major depressive disorder (MDD) is a multifactorial disease which often coexists with cognitive deficits. Depression-induced cognitive deficits are known to be associated with aberrant reward processing, neurochemical and structural alterations. Recent studies have shown that chronic electrical stimulation of brain reward areas induces a robust antidepressant effect. However, the effects of repeated electrical self-stimulation of lateral hypothalamus - medial forebrain bundle (LH-MFB) on depression-induced cognitive deficits and associated neurochemical and structural alterations in the prefrontal cortex (PFC) are unknown.

Objectives

We investigated the effect of chronic rewarding self-stimulation of LH-MFB in neonatal clomipramine (CLI) model of depression. During adulthood, neonatal CLI and saline administered rats were implanted with bilateral electrodes stereotaxically in the LH-MFB and trained to receive intracranial self-stimulation (ICSS) for 14 days. The rats were tested for depressive-like behaviors, learning and memory followed by estimation of PFC volumes, levels of monoamines and its metabolites in the PFC.

Results

We found that chronic ICSS of LH-MFB reverses CLI-induced behavioral despair and anhedonia. Interestingly, self-stimulation normalizes the impaired novel object and location recognition memory in CLI rats. The amelioration of learning impairments in CLI rats was associated with the reversal of volume loss and restoration of monoamine metabolism in the PFC.

Conclusion

We demonstrated that repeated intracranial self-stimulation of LH-MFB ameliorates CLI-induced learning deficits, reverses altered monoamine metabolism and the atrophy of PFC. Our results support the hypothesis that chronic brain stimulation rewarding experience might be evolved as a potential treatment strategy for reversal of learning deficits in depression and associated disorders.  相似文献   
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Soil Microbial Fuel Cells (MFCs) are devices that can generate electricity by using the flooded soil's anode respiring microbial consortium. When the MFC starts to work, the microbial community in the anode vicinity rapidly changes. This shift in the microbial community results in many dead cells that may release their DNA (relic DNA) and obscure culture independent estimates of microbial community composition. Although relic DNA is expected to increase in MFCs, the effect of relic DNA has not been investigated in the soil MFCs system. In this study the effect of the MFCs on the soil microbial community composition within the soil profile and the influence of relic DNA were investigated. Microbial community analysis revealed that the MFCs deployment significantly influenced the community composition within the soil profile. The phylum Proteobacteria (34.4% vs 23.6%) and the class Deltaproteobacteria (16.8% vs 5.9%) significantly increased in the MFCs compared to the control, while the phylum Firmicutes (24.0% vs 28.7%) and the class Sphingobacteria (5.3% vs 7.0%) were more abundant in the control. Furthermore, the archaeal phyla Euryarchaeota (40.7% vs 52.3%) and Bathyarchaeota (10.1% vs 17.3%) were significantly lower in the MFCs, whereas the phylum Woesearchaeota (DHVEG6) (24.4% vs 19.4%) was slightly enhanced. Moreover, the results showed that relic DNA can affect the relative abundance of Geobacter and Candidatus Methanoperedens, however, it has no significant effects on the microbial community structure. These results indicate that MFCs can influence the soil microbial community profile, nevertheless the relic DNA generated has minimum effect on the culture independent estimates of microbial community composition.  相似文献   
4.
目的 通过分析糖尿病高危足患者临床资料及预后,为糖尿病足溃疡的预防提供临床依据。方法 对2012年1月1日-2018年12月31日在四川大学华西医院住院的糖尿病高危足患者进行了回顾性分析,按照既往是否有足溃疡或者截肢(趾)史,分为高风险组和低风险组。比较两组患者的临床特征,并随访患者从出院至2021年1月31日,对患者生存及溃疡复发或新发状况进行了评估。结果 最终纳入患者123例,高风险组患者29例,低风险组患者94例。两组患者的糖尿病病程、吸烟史、饮酒史、受教育程度、接受正规治疗比例、定期监测血糖比例、体质量指数、合并糖尿病周围神经病变、胼胝、足畸形、糖尿病肾病、糖尿病视网膜病变、糖尿病心脏自主神经病变、糖尿病胃肠自主神经病变、高血压、冠心病的比例和实验室检查结果差异无统计学意义(P>0.05)。高风险组的女性比例(51.7%vs. 29.8%)、年龄[(69.8±10.3)vs.(64.4±11.3)岁]、合并下肢动脉病变比例(62.1%vs. 34.4%)、合并高尿酸血症比例(27.6%vs. 10.6%)高于低风险组(P<0.05)。在随访(67±20)个月后,有2...  相似文献   
5.
PurposeTo assess and compare the long-term outcomes of various endovascular interventions in patients with Budd-Chiari syndrome (BCS).Materials and MethodsIn this single-center retrospective study, 510 consecutive patients with BCS who had undergone a total of 618 endovascular procedures from January 2001 to December 2019 were included. Details of the type of endovascular intervention, technical success, clinical success, patency rate, complications, and survival outcomes were analyzed.ResultsThe overall technical success rate was 96% (593 of 618 procedures; 500 in treatment-naïve patients and 93 repeat interventions for recurrent disease). Endovascular procedures included recanalization procedures (angioplasty and stent placement) in 355 patients (71%) and transjugular intrahepatic portosystemic shunt (TIPS) creation in 145 (29%). Major postprocedure complications occurred in 14 patients (2.8%). Vascular/stent restenosis occurred in 95 patients (19%), and successful repeat intervention was performed in 82 of those 95 (86.3%). An additional 11 of these 82 (13.4%) underwent a third intervention for restenosis. In the recanalization and TIPS groups, the 1- and 5-y cumulative patency rates were 87% and 74% and 95% and 68%, respectively. The 1- and 5-y survival rates were 96% and 89% and 90% and 76%, respectively.ConclusionsEndovascular interventions for BCS are feasible and safe in the majority of patients, with excellent short- and long-term patency and survival rates.  相似文献   
6.
Context: The resistance of bacteria to antibiotics is raising serious concern globally. Asian medicinal plants could improve the current treatment strategies for bacterial infections. The antibacterial properties of medicinal plants used by the Khyang tribe in Bangladesh have not been investigated.

Objective: The present study examines the antibacterial properties of 18 medicinal plants used by the Khyang tribe in day-to-day practice against human pathogenic bacteria.

Materials and methods: Leaves, bark, fruits, seeds, roots and rhizomes from collected plants were successively extracted with hexane, ethyl acetate and ethanol. The corresponding 54 extracts were tested against six human pathogenic bacteria by broth microdilution assay. The antibacterial mode of actions of phytoconstituents and their synergistic effect with vancomycin and cefotaxime towards MRSA was determined by time-killing assay and synergistic interaction assay, respectively.

Results and discussion: Hexane extract of bark of Cinnamomum cassia (L.) J. Presl. (Lauraceae) inhibited the growth of MRSA, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and Acinetobacter baumannii with MIC values below 100 µg/mL. From this plant, cinnamaldehyde evoked at 4?×?MIC in 1?h an irreversible decrease of MRSA count Log10 (CFU/mL) from 6 to 0, and was synergistic with vancomycin for MRSA with fractional inhibitory concentration index of 0.3.

Conclusions: Our study provides evidence that the medicinal plants in Bangladesh have high potential to improve the current treatment strategies for bacterial infection.  相似文献   
7.
Damage‐sensing and healing are biological functions which are urgently required in structural health monitoring and remediation of engineering structures. The development of a bio‐inspired multiple cycle damage sensing and triggered healing magnet–polymer nanocomposite (Magpol) is reported. Magpol is comprised of an acrylonitrile butadiene co‐polymer (NBR) matrix and a magnetic nanoparticle (MNP) filler. Magpol nanocomposites in a range of MNP filler concentrations are studied. NBR is selected as the matrix due to its extensive use in industrial coatings, for example, in the automotive industry. Mn‐Zn ferrite MNP is chosen due to its appropriate Curie temperature and good specific absorption rate. Exposure of damaged Magpol to a remote external alternating magnetic field results in MNP heating. The MNP heats the surrounding NBR matrix, resulting in triggered healing. Fractured Magpol samples are successfully healed over several cycles. Incorporation of rhodamine b mechano‐chromophore in Magpol results in multicycle damage sensing by photo‐luminescent absorption. Thus, the developed Magpol is attractive for structural health monitoring and remediation application.  相似文献   
8.
AIM: The objectives of the present study were to evaluate and compare the clinical behavior of resin modified glass ionomer cement (RMGIC) on primary molars with conventional and modified cavity preparations. METHODS AND MATERIALS: Forty-two children, 5-9 years of age, having bilateral initial occlusal caries on the mandibular primary second molars were selected for the study. A split mouth design was employed where conventional Class I cavities with a 90 degrees cavosurface angle were prepared randomly on primary second molars on one side and modified cavities with a 1 mm straight bevel along the cavosurface margin on the contra-lateral side. These cavities were restored with RMGIC. The restorations were evaluated during subsequent visits, for a period of one year. RESULTS: At the end of one year, 90% of the restorations survived in the conventional cavity group whereas 100% of the restorations survived in the modified cavity group. CONCLUSION: Incorporation of a bevel in Class I cavities increases the survival rate of RMGIC restorations. There was no significant difference in the clinical behavior between the two groups. However, beveling does contribute to long term clinical success of these restorations. CLINICAL SIGNIFICANCE: Incorporation of a straight bevel in conventional cavities will improve the retention of RMGIC by increasing the bonding area and enhancing the desired properties of the material.  相似文献   
9.
The objectives of this study were to evaluate and compare the amount and pattern of fluoride release from teeth after topical application of 2% NaF, 8% SnF2 and 1.23% APF at different time intervals. The growth inhibitory effects of this released fluoride ion was assessed on mutans streptococci (MS) and correlated with the fluoride release. Forty premolars divided into four groups were subjected to different topical fluoride treatments. All the teeth were immersed individually in deionized water and were transferred to containers at 1 hour, 1 day and 1 week time intervals. 240 samples in total were used for fluoride estimation by ion selective electrode method and the samples from the other subgroup were used for evaluation of antimicrobial activity on mutans streptococci (MS) by bacterial inhibition assay method. The results showed that the highest fluoride release (7.83 +/- 0.55 ppm) was seen in SnF2 treated specimens, as compared to that of NaF (3.71 +/- 0.60ppm) and APF (3.30 +/- 0.51ppm), the difference being statistically significant (P<0.01). This was observed immediately after 1 hour, followed by a drastic reduction thereafter. No zones of inhibition were observed at the released fluoride concentrations at different time intervals in the different groups. IN CONCLUSION: 8% SnF2 is expected to have greater anticaries property from the high fluoride releasing property for prolonged period of time.  相似文献   
10.
The prevalence of asthma has been increasing since the 1980s. Asthma and tooth decay are the two major causes of school absenteeism. There are few studies present in the literature. The objectives of the present study were to know the severity of dental caries and periodontal problems in children before and after taking antiasthmatic medication. The present study was conducted on 105, six- to fourteen-year-old asthmatic children to determine the condition of their dental caries and their periodontal status before and after taking antiasthmatic medication, for a period of 1 year and these were matched with their controls. The results showed that salbutamol inhaler shows increased caries rate with high significance over other groups, which was followed by salbutamol tablets and beclamethasone inhaler respectively. It has been concluded that antiasthmatic medication has its effects on dental caries and periodontal disease and asthmatic patients are recommended to adopt more precautionary oral hygiene practices and keep their caries activity and periodontal health under constant check.  相似文献   
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