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糖尿病足早期症状不明显,待明确诊断时病程多已步入中后期阶段,严重威胁民众健康。红外热成像技术作为一种医用功能性检测技术,能在人体组织发生结构性病变之前,敏感地发现其功能性改变导致的体表温度异常。基于中医学视角,借用计算机辅助诊断系统及属性篇序结构图,可以为糖尿病足红外热图的多角度、多维度解读提供全新思路,突破传统西医解剖学视角难以全面解读热图异常规律的瓶颈,也为红外热成像技术的应用拓宽视野。  相似文献   
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目的 观察膝骨性关节炎患者穴位体表温度分布规律。方法 以256例膝骨性关节炎患者和256例健康受试者为观察对象。使用Fotric 226红外热像仪检测患者和健康受试者腧穴的温度值,每名患者每周固定时间检测1次,共检测4次,健康人检测1次,比较患者组与健康受试者组穴位温度值的差异,比较不同时间点不同部位、经脉温度值的差异。结果 膝骨性关节炎患者血海穴、鹤顶穴、梁丘穴、曲泉穴、内膝眼穴、犊鼻穴、委阳穴、阴陵泉穴、膝关穴、阳陵泉穴、大杼穴、悬钟穴、足三里穴、命门穴、腰阳关穴温度值高于健康受试者(P < 0.05);患者组胃经的4次皮温均较高(P < 0.05),腰背部的4次皮温均较高(P < 0.05);KOA相关腧穴4次温度值变化趋势不显著(P > 0.05)。结论 膝关节骨性关节炎患者部分腧穴皮温升高;膝骨性关节炎患者的穴位升温现象具有规律性,与经络、部位相关;膝关节骨性关节炎相关穴位升温效应具有稳定性。  相似文献   
4.
BackgroundPathological conditions with ongoing inflammatory processes result in specific heat signatures at the affected body parts; infrared thermography (IRT) detects these changes and can be utilied in screening such conditions. The modern devices are advanced and their non contact, convenient and precise readings can aid in multiple medical sub fields. Orthopaedics as a broad entity has witnessed utilisation of this technology for different indications and the present scoping review was done to assess these established indications and further scope of its utility.Methodology: A Medline search was done on April 26, 2021 with specific keywords for studies of any design in English language discussing the usage of thermography in Orthopaedics. Animal studies, conference abstracts, systematic reviews, e-posters, case reports, book chapters, and studies describing the use of thermography in non-Orthopaedic patients were excluded.ResultsTotal number of hits were 1380. 43 studies including case series and case control studies were included in the review. The subfields or indications described were pain/arthritis, Charcot's foot/neuropathic ulcers, infections associated with diabetic feet and arthroplasties, reflex sympathetic dystrophy, carpal tunnel syndrome, sports medicine, paediatric orthopaedics, spine, ergonomics and compartment syndrome.ConclusionIRT has been described to be effective in orthopaedic conditions with specific heat signatures and this can assess the trend of the ongoing inflammatory process as well as response to a particular treatment. Additionally, it can specifically determine the exact loci of the pathology for targeted interventions.  相似文献   
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BackgroundThe independent role of solar radiation in the differential melanogenesis between melasma and adjacent skin is unknown.ObjectivesTo assess the melanogenic responses of skin with facial melasma and of the adjacent skin to UVB, UVA, and visible light, in an ex vivo model.MethodsThis was a quasi-experimental study involving 22 patients with melasma. Facial melasma and adjacent skin samples were collected and stored in DMEM medium, at room temperature. One fragment was placed under the protection from light, while another was exposed to UVB, UVA, and visible light (blue-violet component): 166 mJ/cm2, 1.524 J/cm2, and 40 J/cm2, respectively. Subsequently, all samples were kept for 72 hours in a dark environment and stained by Fontana-Masson to assess basal layer pigmentation, dendrites, and melanin granulation.ResultsEffective melanogenesis was observed in the basal layer in melasma and in the normal adjacent skin after all irradiations (p < 0.01), with the following median increment: UVB (4.7% vs. 8.5%), UVA (9.5% vs. 9.9%), and visible light (6.8% vs. 11.7%), with no significant difference between anatomical sites. An increase in melanin granulation (coarser melanosomes) was observed only after irradiation with UVA and only in the skin with melasma (p = 0.05). An increase in the melanocyte dendrite count induced by UVB radiation was observed in both anatomical sites (p ≤ 0.05).Study limitationsUse of an ex vivo model, with independent irradiation regimes for UVB, UVA, and visible light.ConclusionsMelanogenesis induced by UVB, UVA, and visible light was observed both in melasma and in the adjacent skin. The morphological patterns suggest that different irradiations promote individualized responses on the skin with melasma.  相似文献   
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Background and objectiveThe minimal erythema dose (MED), an essential measurement in studies of skin photosensitivity, requires establishing MED values for specific populations, given genetic variation. Different ways to assess erythema are also relevant. We aimed to determine MED values in a sample of Colombian patients and correlations between MED and Fitzpatrick skin type. We also studied concordance correlation between MEDs and two alternative ways to assess erythema.Patients and methodsCross-sectional study of 113 individuals in Bogotá, Colombia. We used a solar simulator to measure UV-A radiation and combined UV-A and UV-B (UVA + UVB) radiation, o se podría suprimir este término porque UVA y UVB son términos conocidos for MED calculation. Narrowband UV-B (NBUVB) radiation was measured in a phototherapy cabin. Erythema was assessed visually and with a Mexameter MX 18 device.ResultsThe median MEDs of UVA + UVB radiation were 22 mJ/cm2 for Fitzpatrick skin types I and II, and 33 and 43 mJ/cm2, respectively, for types III and IV. The MEDs of UV-A radiation were 22, 42, 86, and 100 J/cm2 for types I, II, III, and IV, respectively. The MEDs of NBUVB light were 390, 550, 770, and 885 mJ/cm2 for the 4 skin types. The correlation between MEDs and skin types ranged from 0.5 to 0.69. Lin's concordance correlation coefficients between visual and Mexameter assessments of erythema were greater than 0.8 in all cases.ConclusionThis study allowed us to understand MED values for UV-A, UVA + UVB, and NBUVB according to different skin types in the Colombian population. Concordance correlation coefficients between the different methods of erythema assessment were very good. Correlations between MEDs and skin types were moderate to good.  相似文献   
7.
【摘要】 目的 探讨外源性胆绿素对中波紫外线(UVB)照射的HaCaT细胞光损伤的保护作用。方法 将HaCaT细胞分为加入0、0.1、1、10 μmol/L胆绿素并照射UVB的UVB组、0.1 μmol/L UVB组、1 μmol/L UVB组、10 μmol/L UVB组及不做处理的对照组。UVB照射剂量为30 mJ/cm2,照射后继续培养24 h,分别检测细胞活性氧(ROS)水平、超氧化物歧化酶(SOD)活力、丙二醛(MDA)含量,ELISA法检测各组细胞的炎症因子白细胞介素6(IL-6)、IL-8水平。多组间均数比较采用单因素方差分析,组间两两比较采用LSD-t检验。结果 UVB组、0.1 μmol/L UVB 组、1 μmol/L UVB组、10 μmol/L UVB组、对照组细胞ROS水平(3 613.33 ± 206.61、2 958.67 ± 193.87、2 678.33 ± 178.24、2 274.67 ± 118.81、1 905.67 ± 250.25)、SOD活力(24.41 ± 1.78、28.96 ± 2.21、29.75 ± 1.75、30.19 ± 2.29、37.52 ± 2.31)、MDA含量(5.61 ± 0.32、5.46 ± 0.55、4.65 ± 0.22、2.55 ± 0.93、1.31 ± 0.05)、IL-6水平、IL-8水平差异均有统计学意义(F值分别为 34.02、57.36、214.09、29.73、11.40,均P < 0.05),UVB组ROS水平、MDA含量及IL-6、IL-8水平均高于另4组(均P < 0.05),SOD活力均低于另4组(均P < 0.05)。结论 外源性胆绿素减轻UVB引起的HaCaT细胞的氧化损伤、减轻炎症反应和抑制脂质过氧化作用,对细胞光损伤有一定的保护作用。  相似文献   
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ObjectivesDifferentiating cellulitis from pseudocellulitis is challenging, and misdiagnosis leads to unnecessary antimicrobial use and increased healthcare expenditure. Clinical diagnosis remains the criterion standard and may involve expert consultation. Our objective was to evaluate the usefulness of a handheld infrared thermometer to improve diagnostic certainty in cases of suspected cellulitis.MethodsWe conducted a cross-sectional study from August 2018 to January 2020 at a tertiary-care hospital in Montreal, Canada. We enrolled adult patients with suspected limb cellulitis. Using the infrared thermometer, we compared the average temperature of the affected area with that of the contralateral limb, and we used Youden's method to determine the optimal temperature difference which best differentiated cellulitis from pseudocellulitis as determined by an independent and blinded infectious diseases specialist. We used bootstrapping to estimate 95% confidence intervals for the sensitivity, specificity, and area under the receiver operating curve.ResultsOf 65 patients screened for enrolment, 52 patients were recruited (median age: 64 years, IQR 52–76); 39 of these were diagnosed with cellulitis and 13 were not. The mean temperature difference between affected and unaffected limbs was 2.6°C (95%CI 2.1–3.1°C) for patients with cellulitis and 0.4°C (95%CI –1.2°C to 2.1°C) for patients without (p < 0.001). An average temperature difference between limbs of 0.8°C or more was 95% sensitive (95%CI 74–100%) and 69% specific (95%CI 44–95%) for the diagnosis of cellulitis (c-statistic 0.82).ConclusionsIn this proof-of-concept single-centre study, a handheld infrared thermometer was a useful aid to differentiate cellulitis from pseudocellulitis.  相似文献   
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Sodium copper chlorophyllin (SCC) has a genetic damage inhibitory capacity due to its antioxidant action. For this reason, it was considered to investigate its role in the life span of Drosophila melanogaster and its relationship with the frequency of somatic mutation induced by gamma rays. Results indicated that SCC alone prolonged the lifespan only in females, but in combination with 20 Gy of gamma rays, the aging delay in both sexes was significant. In addition to confirming that the porphyrin reduces the frequency of mutation, the individuals with the highest mutation load are the individuals who die more quickly, and once they are eliminated, the survivor individuals treated with 20 Gy or with SCC + 20 Gy, died at the same rate. The results together indicate that SCC not only inhibits induced genetic damage, but it also has beneficial effects that probably cause an aging delay of the treated population that need to be investigated.  相似文献   
10.
Timely detection is crucial for successful treatment of cancer. The current study describes a new approach that involves utilization of the tumor cell environment for bioimaging with in-situ biosynthesized nanoscale gold and iron probes and subsequent dissemination of Au-Fe nanoclusters from cargo exosomes within the circulatory system. We have isolated the Au-Fe cargo exosomes from the blood of the treated murine models after in situ biosyntheses from their respective pre-ionic solutions (HAuCl4, FeCl2), whereas Na2SeO3 supplementation added into Au lethal effect. The microarray data of various differentially expressed genes revealed the up-regulated tumor ablation and metal binding genes in SGC-7901 cell lines after treatment with Au-Fe-Se triplet ionic solution. The isolation of Au-Fe nanoclusters cargo exosomes (nano in nano) after secretion from deeply seated tumors may help in early diagnosis and reveal the tumor ablation status during and after the relevant treatment like radio-chemo therapies et al.  相似文献   
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