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31.
This study evaluates the biological properties of a new pulp capping material developed from Portland cement. This study was conducted on 48 teeth in 4 dogs (12 teeth/dog). The dogs were classified into two equal groups (n = 24 teeth) according to the evaluation period including: group A (3 weeks) and group B (3 months). Each group was further subdivided into three equal subgroups (n = 8 teeth) according to the capping material including: subgroup 1: mineral trioxide aggregate (MTA), subgroup2: Portland cement + 10% calcium hydroxide + 20% bismuth oxide (Port Cal) and subgroup 3: Portland cement + bismuth oxide. After general anesthesia, a class V buccal cavity was prepared coronal to the gingival margin. After pulp exposure and hemostasis,the capping materials and glass ionomer filling were placed on the exposure sites. All histopathological findings, inflammatory cell count and dentin bridge formation were recorded. Data were analyzed statistically. After 3 months, the histopathological picture of the pulp in subgroup 1 showed normal pulp, continuous odontoblastic layer and complete dentin bridge formation while subgroup 2 showed partial and complete dentin bridge over a normal and necrotic pulps. Subgroup 3 showed loss of normal architecture, areas of necrosis, complete, or incomplete dentin bridge formation, attached and detached pulp stones and fatty degeneration in group B. For group A, MTA subgroup showed the least number of inflammatory cell infiltrate followed by Port Cal subgroup. While subgroup 3 showed the highest number of inflammatory cell infiltrate. For group B, the mean inflammatory cell count increased with the three tested materials with no statistical difference. Regarding dentin bridge formation at group A, no significant differences was found between subgroups, while at group B, MTA subgroup exhibited significantly higher scores than other subgroups. In conclusion, addition of calcium hydroxide to Portland cement improves the dentin bridge formation qualitatively and quantitatively.  相似文献   
32.
麦胚提取物对去卵巢大鼠无机盐和骨形成蛋白2的影响   总被引:2,自引:0,他引:2  
目的 探讨麦胚提取物对去卵巢引起骨质疏松大鼠无机盐和骨形成蛋白 2 (BMP2 )的影响。方法  2 1只雌性 SD大鼠随机分为假手术组、去卵巢模型组、去卵巢加麦胚提取物组 (麦胚提取物 1 0 0 mg/ kg· d) ,1 0 w后测定血清无机盐钙、磷、钠、钾、AL P含量 ,用 SP免疫组织化学检测骨 BMP2 表达。结果 去卵巢组大鼠试验 1 0 w后血清和尿钙、钠和血清 ALP含量显著升高 ;而血清和尿钾降低 ,骨 BMP2 表达下降 (P<0 .0 5或 P<0 .0 1 )。去卵巢加麦胚后大鼠的尿钙、钠和血清 ALP含量显著降低 ,骨 BMP2 表达增高 (P<0 .0 5)。结论 麦胚提取物可调节去卵巢大鼠血清和尿中钙、钠、钾 ,促进 BMP2 表达 ,预防去卵巢大鼠骨质疏松。  相似文献   
33.
We report a case where recurrent "pneumonia" was eventually diagnosed as lipoid pneumonia in an elderly patient with cerebrovascular disease. The discontinuation of paraffin oil laxative led to clinical improvement. Lipoid pneumonia, a foreign body-type reaction to the presence of lipid within lung parenchyma, is probably underdiagnosed and underreported, and paraffin oil laxative is the main causative agent. Paraffin oil is marketed as a food additive, and no information about its hazards is provided to clinicians or patients. We suggest that a change in paraffin oil licensing may decrease the incidence of lipoid pneumonia.  相似文献   
34.
The P, Na, K, Ca, Mg, Fe, Cu, Zn and Mn concentrations were determined in seventy-three samples of seaweeds belonging to different genera (classified as brown, red and green seaweeds), which were collected from three zones in the sub-Antarctic ecoregion of Magallanes (Chile). There were clear differences in the concentrations between the considered genera. Brown seaweed had the highest mean K (31.4 g/kg) and Ca (10.3 g/kg) concentrations compared with red (14.1 g/kg for K and 3.11 g/kg for Ca) and green (13.9 g/kg for K and 7.58 g/kg for Ca) seaweed, and green seaweed had the highest mean Mg (15.0 g/kg), Fe (1260 mg/kg) and Cu (7.46 mg/kg) concentrations. The consumption of a serving (8 g) from of the three groups of brown, red and green seaweed is a good source of Fe, Mg and Mn (>25% of the Dietary Recommended Intake). Significant differences were observed in the mean concentrations of all the minerals and trace elements, except for Fe, Cu and Mn, between the three collection zones. Factor and discriminant analysis were used to differentiate the type of seaweed and sampling zone. Besides which, good classifications were obtained according to the type of seaweed using discriminant analysis.  相似文献   
35.
Introduction The semantic interoperability of electronic healthcare records (EHRs) systems is a major challenge in the medical informatics area. International initiatives pursue the use of semantically interoperable clinical models, and ontologies have frequently been used in semantic interoperability efforts. The objective of this paper is to propose a generic, ontology-based, flexible approach for supporting the automatic transformation of clinical models, which is illustrated for the transformation of Clinical Element Models (CEMs) into openEHR archetypes.Methods Our transformation method exploits the fact that the information models of the most relevant EHR specifications are available in the Web Ontology Language (OWL). The transformation approach is based on defining mappings between those ontological structures. We propose a way in which CEM entities can be transformed into openEHR by using transformation templates and OWL as common representation formalism. The transformation architecture exploits the reasoning and inferencing capabilities of OWL technologies.Results We have devised a generic, flexible approach for the transformation of clinical models, implemented for the unidirectional transformation from CEM to openEHR, a series of reusable transformation templates, a proof-of-concept implementation, and a set of openEHR archetypes that validate the methodological approach.Conclusions We have been able to transform CEM into archetypes in an automatic, flexible, reusable transformation approach that could be extended to other clinical model specifications. We exploit the potential of OWL technologies for supporting the transformation process. We believe that our approach could be useful for international efforts in the area of semantic interoperability of EHR systems.  相似文献   
36.
Osteoporosis is a major public health problem with serious long-term complications. In children, the definition of osteoporosis is not only based on densitometric criteria but also takes into account vertebral and long bone fragility fractures. Several factors, such as long-term high-dose steroids, chronic inflammation, malnutrition, immobility, lack of sex steroids, and medication can reduce bone density and increase the risk for fragility fractures when left untreated. Also, genetic conditions can predispose to primary bone fragility disorders, with osteogenesis imperfecta being the most common. Furthermore, since the growing skeleton is at an increased rate of bone remodeling, the ability to heal long bone fractures and reshape vertebral fractures differentiates children from adults. The scope of this chapter is to review the risk factors of osteoporosis and fragility fractures and describe the commonest causes of primary and secondary osteoporosis and their management in children and young adults.  相似文献   
37.
目的通过比较新型生物陶瓷材料iRoot BP Plus和三氧化矿物凝聚体(mineral trioxide aggregate,MTA)作为盖髓剂在乳磨牙牙髓切断术应用中的成功率,探讨iRoot BP Plus的临床应用价值。方法按照纳入和排除标准收集2018年8至12月于北京大学口腔医学院·口腔医院儿童口腔科行全身麻醉下治疗,口内至少有1对及以上同名乳磨牙龋坏须行牙髓切断术的3至8岁患儿,采用简单随机分组方法分别使用iRoot BP Plus(试验组)和MTA(对照组)行牙髓切断术,术后3、6及12个月随访,拍摄患牙根尖X线片,收集患牙治疗前后自觉症状、临床检查及影像学表现,计算两组的治疗成功率,并分析影响成功率的因素。结果研究共纳入患儿20例,男女各10例,共计28对、56颗乳磨牙(试验组28颗,对照组28颗),其中随访满1年者共23对、46颗乳磨牙。试验组3、6、12个月的治疗成功率分别为96%(25/26)、92%(22/24)和87%(20/23),对照组分别为100%(26/26)、96%(23/24)和96%(22/23),两组术后3、6、12个月的成功率差异均无统计学意义(P>0.05)。切髓后止血时间显著影响试验组的成功率(P<0.05)。结论iRoot BP Plus与MTA用于乳磨牙牙髓切断术1年随访期内均取得了较好的治疗效果,iRoot BP Plus在乳牙牙髓切断术中具有良好的临床应用前景。  相似文献   
38.
Both hyperphosphatemia and hypophosphatemia are associated with increased morbidity and mortality among patients on dialysis. The control of serum phosphate concentration is a considerable clinical problem. Our study aimed to improve understanding of phosphate kinetics in patients on dialysis using mathematical modeling. Three consecutive hemodialysis sessions with breaks of 2–2–3 days were monitored in 25 patients. Phosphate concentration was measured every hour and 45 min after the end of dialysis in blood serum and every 30 min in dialysate during each session. Volume of fluid compartments and body composition were assessed by bioimpedance. The pseudo one‐compartment model was applied to describe the profile of phosphate in blood serum during intra‐ and interdialytic periods of 1‐week cycle of three hemodialysis sessions. Model parameters, such as phosphate internal clearance (KM) and the rate of phosphate mobilization (RM), were correlated with the reduction of serum phosphate concentration during dialysis (Cpost/Cpre) and with equivalent continuous clearance (ECC) for phosphate. KM correlated negatively with predialysis serum phosphate concentration. There was significant positive correlation between RM and age. Postdialysis volume of phosphate central compartment was lower than, but correlated to, extracellular water volume. Parameters of the pseudo one‐compartment model, phosphate internal clearance, and the rate of phosphate inflow to the central compartment (the one accessible for dialysis) from other phosphate body reservoirs correlated with the indices of dialysis adequacy, such as reduction of serum phosphate and ECC. The pseudo one‐compartment model can be successfully extended from a single hemodialysis to the standard weekly cycle of sessions and the model parameters strongly correlate with the adequacy parameters of dialytic removal of phosphate.  相似文献   
39.
随着生活水平和饮食结构的改变,高尿酸血症的发病率呈不断上升趋势,流行病学调查显示,我国成年人高尿酸血症的患病率为8.4%~13.3%,高尿酸血症不仅是痛风的主要病因,而且是慢性肾脏病(CKD)进展和心血管疾病死亡的独立危险因素,已经成为威胁人类健康的代谢性疾病之一。矿物质和骨代谢异常(MBD)是CKD常见的并发症,其包括矿物质代谢紊乱、骨骼病变和骨外钙化,可导致CKD患者住院率、心血管事件及死亡率增加。近年研究发现尿酸与CKD-MBD之间可能密切相关,但其相关性目前仍存在争议,尚需深入研究论证。本文综述了尿酸的病理生理功能、尿酸与CKD-MBD的关系及相互作用机制的研究进展,认为调控尿酸水平可能成为CKD-MBD治疗的靶点。  相似文献   
40.
We propose a model of an equivalent electrical circuit specifically designed for a ferrite indAuctor excited by a sinusoidal waveform. The purpose of this model is its use in a circuit simulator. We calculate the model parameters by means of Finite Elements in 2D which leads to significant computational advantages over the 3D model. We carry out the validation for a toroidal ferrite inductor by comparing the experimental results and computed ones. We consider the saturation and power losses in the core. In addition, we have tested the model for the case of square waveform in order to generalize the results. We find excellent agreement between the experimental data and the results obtained by numerical calculations.  相似文献   
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