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51.
52.
Metastatic tumors to the heart usually involve right sided chambers. We report a rare case of malignant phyllodes tumor of breast with metastatic involvement of left atrium occurring through direct invasion from mediastinal micro-metastasis and presenting as a left atrial mass causing arrhythmia.  相似文献   
53.

Background

There is increasing recognition of association of nonalcoholic fatty liver disease (NAFLD) with cardiovascular disease (CVD). Metabolic syndrome is common in both NAFLD and cardiovascular diseases. Our study is designed to investigate the association of NAFLD with cardiovascular disease.

Methods

It''s a cross-sectional study which included 104 patients of coronary artery disease and hypertensive heart disease. Those patients having secondary causes of steatosis were excluded. Complete cardiovascular evaluation which included assessment of metabolic syndrome, routine biochemistries, viral markers, Ultrasonography (USG) abdomen, hs-CRP and TNF-α levels were obtained for all patients.

Results

Of all patients with cardiovascular disease, 19.2% (20/104) had essential hypertension with hypertensive heart disease the remaining 80.8% (84/104) patients had ischemic heart disease (IHD). On USG 69.2% (72/104) had NAFLD, these 50% (36/72) had grade 1 NAFLD and the rest grade 2 NAFLD. The hs-CRP levels and TNF-α were significantly higher in patients with NAFLD (p-value <0.001) and within patients with NAFLD the levels were higher in patients with grade 2 NAFLD. Also, binary logistic regression showed that high body-mass index (BMI), raised serum triglyceride levels, increased waist circumference and hypertension were significantly associated with the presence of NAFLD.

Conclusion

Our data indicates that NALD is highly prevalent in patients of cardiovascular disease (69.2%) and is significantly associated with metabolic syndrome and its individual components. The levels of hs-CRP and TNF-α were significantly higher in patients with NAFLD and showed an increasing trend with the severity of fatty liver.  相似文献   
54.

INTRODUCTION

Open surgical release for carpal tunnel syndrome is not devoid of complications and its quantitative assessment with the Boston questionnaire in a developing country had not been conducted, where, lack of facilities and surgical technique can influence the outcome.

PRESENTATION OF CASE

This was a prospective study in which all cases of carpal tunnel syndrome undergoing open release between June 2007 and June 2012 and who returned for follow up were included. Each patient was requested to fill out the Boston questionnaire twice both pre and post op at 3 months. All complications were recorded as well as bio-data of patients and co morbidities. Follow up was at 2 weeks and at 3 months. Those reporting complications at 3 months were further followed up until 6 months. 373 patients were included in the study. Twenty four patients developed complications. Of these, 12 experienced pain resulting from reflex sympathetic dystrophy. Three patients developed wound dehiscence, 2 cases acquired infections, 4 patients developed immediate post-operative haemorrhage and in 3 patients there was late recurrence of median nerve compression. The symptom severity score pre-operatively was 3.30 (±0.60) and it improved to 1.65 (±0.75) post-operatively indicating a significant change (p < 0.0001). The preoperative functional status score was 2.58 (±0.75) and post-op it became 1.60 (±0.80) again implying a good improvement with an effect size of 1.3.

DISCUSSION

All of the complications produced were well managed. The complication incidence was low. The open release procedure produced good improvement in hand function and in decreasing the symptom severity.

CONCLUSION

Conducting open release for carpal tunnel syndrome in a tertiary referral centre in a developing country offers a good outcome.  相似文献   
55.
Methane is the main component of biogas, which could be used as a renewable energy source for electricity, source of heat, and biofuel production after upgrading from biogas. It also contains toxic compounds which cause environmental and human health problems. Therefore, in this work, the removal of a toxic compound (toluene) from methane gas was studied using a dielectric barrier discharge (DBD) reactor. It was observed that the removal of the toxic compound could be achieved from methane carrier gas using a dielectric barrier discharge reactor, and it depends on plasma input power. The maximum removal of the toxic compound was 85.9% at 40 W and 2.86 s. The major gaseous products were H2 and lower hydrocarbons (LHC) and the yield of these products also increases with input power. In the current study, the yield of gaseous products depends on the decomposition of toxic compounds and methane, because the decomposition of methane also produces H2 and lower hydrocarbons. The percentage yield of H2 increases from 0.43–4.74%. Similarly, the yield of LHC increases from 0.56–7.54% under the same reaction conditions. Hence, input power promoted the decomposition of the toxic compound and enhanced the yield of gaseous products.

The removal of toluene as a toxic volatile organic compound from methane gas, which is the major component of biogas, is carried out using a non-thermal plasma dielectric barrier discharge reactor.  相似文献   
56.
This study reports substantial improvement in the process for oxidising α-pinene, using environmentally friendly H2O2 at high atom economy (∼93%) and selectivity to α-pinene oxide (100%). The epoxidation of α-pinene with H2O2 was catalysed by tungsten-based polyoxometalates without any solvent. The variables in the screening parameters were temperatures (30–70 °C), oxidant amount (100–200 mol%), acid concentrations (0.02–0.09 M) and solvent types (i.e., 1,2-dichloroethane, toluene, p-cymene and acetonitrile). Screening the process parameters revealed that almost 100% selective epoxidation of α-pinene to α-pinene oxide was possible with negligible side product formation within a short reaction time (∼20 min), using process conditions of a 50 °C temperature in the absence of solvent and α-pinene/H2O2/catalyst molar ratio of 5 : 1 : 0.01. A kinetic investigation showed that the reaction was first-order for α-pinene and catalyst concentration, and a fractional order (∼0.5) for H2O2 concentration. The activation energy (Ea) for the epoxidation of α-pinene was ∼35 kJ mol−1. The advantages of the epoxidation reported here are that the reaction could be performed isothermally in an organic solvent-free environment to enhance the reaction rate, achieving nearly 100% selectivity to α-pinene oxide.

Products obtained from the oxidation of α-pinene with hydrogen peroxide (H2O2) in the presence of tungsten-based polyoxometalates (α-pinene 1, α-pinene oxide 2, pinanediol 3, campholenic aldehyde 4, sobrerol 5, verbenol 6 and verbenone 7).  相似文献   
57.
IntroductionThere is a growing population of children who are HIV‐exposed and uninfected (HEU) with the successful expansion of antiretroviral therapy (ART) use in pregnancy. Children who are HEU are at risk of delayed neurodevelopment; however, there is limited research on early brain growth and maturation. We aimed to investigate the effects of in utero exposure to HIV/ART on brain structure of infants who are HEU compared to HIV‐unexposed (HU).MethodsMagnetic resonance imaging using a T2‐weighted sequence was undertaken in a subgroup of infants aged 2–6 weeks enrolled in the Drakenstein Child Health Study birth cohort, South Africa, between 2012 and 2015. Mother–child pairs received antenatal and postnatal HIV testing and ART per local guidelines. We compared subcortical and total grey matter volumes between HEU and HU groups using multivariable linear regression adjusting for infant age, sex, intracranial volume and socio‐economic variables. We further assessed associations between brain volumes with maternal CD4 cell count and ART exposure.ResultsOne hundred forty‐six infants (40 HEU; 106 HU) with high‐resolution images were included in this analysis (mean age 3 weeks; 50.7% male). All infants who were HEU were exposed to ART (88% maternal triple ART). Infants who were HEU had smaller caudate volumes bilaterally (5.4% reduction, p < 0.05) compared to HU infants. There were no group differences in other subcortical volumes (all p > 0.2). Total grey matter volume was also reduced in infants who were HEU (2.1% reduction, p < 0.05). Exploratory analyses showed that low maternal CD4 cell count (<350 cells/mm3) was associated with decreased infant grey matter volumes. There was no relationship between timing of ART exposure and grey matter volumes.ConclusionsLower caudate and total grey matter volumes were found in infants who were HEU compared to HU in the first weeks of life, and maternal immunosuppression was associated with reduced volumes. These findings suggest that antenatal HIV exposure may impact early structural brain development and improved antenatal HIV management may have the potential to optimize neurodevelopmental outcomes of children who are HEU.  相似文献   
58.
The epiploic appendages (also known as appendices epiploicae) are usually located on the anti‐mesenteric surface of the colon, extending from the caecum to the rectosigmoid, and epiploic appendagitis (EA) is the inflammation of these appendages. We report a clinical image of epiploic appendagitis creating a diagnostic challenge.  相似文献   
59.
The consumption of waste materials in the construction sector is a sustainable approach that helps in reducing the environmental pollution and decreases the construction cost. The present research work emphasizes the mechanical properties of bituminous concrete mix prepared with crumb rubber (CR) and waste sugarcane bagasse ash (SCBA). For the preparation of bituminous concrete mix specimens with CR and SCBA, the effective bitumen content was determined using the Marshall Mix design method. A total of 15 bituminous concrete mix specimens with 4%, 4.5%, 5%, 5.5% and 6% of bitumen content were prepared, and the effective bitumen content turned out to be 4.7%. The effect of five different CR samples of 2%, 4%, 6%, 8% and 10% by weight of total mix and SCBA samples of 25%, 50%, 75% and 100% by weight of filler were investigated on the performance of bituminous concrete. A total of 180 samples with different percentages of CR and SCBA were tested for indirect tensile strength (ITS) and Marshall Stability, and the results were compared with conventional bituminous concrete mix. It was observed that the stability values rose with an increase in CR percentage up to 6%, while the flow values rose as the percentage of SCBA increased in the mix. Maximum ITS results were observed at 4% CR and 25% SCBA replacement levels. However, a decrease in stability and ITS result was observed as the percentages of CR and SCBA increased beyond 4% and 25%, respectively. We concluded that the optimum CR and SCBA content of 4% and 25%, respectively, can be effectively used as a sustainable alternative in bituminous concrete mix.  相似文献   
60.
Boron nitride (BN) nanomaterials are rapidly being investigated for potential applications in biomedical sciences due to their exceptional physico-chemical characteristics. However, their safe use demands a thorough understanding of their possible environmental and toxicological effects. The cytotoxicity of boron nitride nanotubes (BNNTs) was explored to see if they could be used in living cell imaging. It was observed that the cytotoxicity of BNNTs is higher in cancer cells (65 and 80%) than in normal cell lines (40 and 60%) for 24 h and 48 h respectively. The influence of multiple experimental parameters such as pH, time, amount of catalyst, and initial dye concentration on percentage degradation efficiency was also examined for both catalyst and dye. The degradation effectiveness decreases (92 to 25%) as the original concentration of dye increases (5–50 ppm) due to a decrease in the availability of adsorption sites. Similarly, the degradation efficiency improves up to 90% as the concentration of catalyst increases (0.01–0.05 g) due to an increase in the adsorption sites. The influence of pH was also investigated, the highest degradation efficiency for MO dye was observed at pH 4. Our results show that lower concentrations of BNNTs can be employed in biomedical applications. Dye degradation properties of BNNTs suggest that it can be a potential candidate as a wastewater and air treatment material.

Photocatalytic degradation studies of methyl orange using BNNTs.  相似文献   
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