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61.
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   
62.
Osteoarthritis (OA) is a painful disease, characterized by progressive surface erosion of articular cartilage. The use of human articular chondrocytes (hACs) sourced from OA patients has been proposed as a potential therapy for cartilage repair, but this approach is limited by the lack of scalable methods to produce clinically relevant quantities of cartilage‐generating cells. Previous studies in static culture have shown that hACs co‐cultured with human mesenchymal stem cells (hMSCs) as 3D pellets can upregulate proliferation and generate neocartilage with enhanced functional matrix formation relative to that produced from either cell type alone. However, because static culture flasks are not readily amenable to scale up, scalable suspension bioreactors were investigated to determine if they could support the co‐culture of hMSCs and OA hACs under serum‐free conditions to facilitate clinical translation of this approach. When hACs and hMSCs (1:3 ratio) were inoculated at 20,000 cells/ml into 125‐ml suspension bioreactors and fed weekly, they spontaneously formed 3D aggregates and proliferated, resulting in a 4.75‐fold increase over 16 days. Whereas the apparent growth rate was lower than that achieved during co‐culture as a 2D monolayer in static culture flasks, bioreactor co‐culture as 3D aggregates resulted in a significantly lower collagen I to II mRNA expression ratio and more than double the glycosaminoglycan/DNA content (5.8 vs. 2.5 μg/μg). The proliferation of hMSCs and hACs as 3D aggregates in serum‐free suspension culture demonstrates that scalable bioreactors represent an accessible platform capable of supporting the generation of clinical quantities of cells for use in cell‐based cartilage repair.  相似文献   
63.
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   
64.
维甲酸、三氧化二砷诱导NB4细胞TRAIL基因表达的研究   总被引:1,自引:0,他引:1  
目的:研究全反式维甲酸(ATRA)或三氧化二砷(As2O3)诱导急性早幼粒细胞白血病(APL)NB4细胞肿瘤坏死因子相关的凋亡诱导配体(TRAIL)基因的表达及其治疗APL的机制。方法:采用RT—PCR检测TRAIL基因表达的变化。结果:10^-6mol/L的ATRA作用6h或10^-6mol/L的As2O3作用12h,即可诱导TRAIL基因表达。结论:ATRA或As2O3能诱导NB4细胞TRAIL基因表达,TRAIL基因可能以类似“旁分泌”的作用方式杀伤NB4细胞。诱导TRAIL基因介导的细胞凋亡可能是ATRA或As2O3治疗APL的机制之一。  相似文献   
65.
Data regarding the role of mitochondria in arsenic trioxide (As2O3)-induced apoptosis are controversial. We investigated the contribution of caspases and mitochondrial depolarization to As2O3-induced apoptosis in the myeloid cell lines NB-4, HL-60 and U-937. Caspase inhibition reduced the amount of cells with As2O3 (20 micromol/l)-induced mitochondrial depolarization by about 50% in all cell lines. As2O3 also induced dose-dependent phosphatidylserine exposure in cells without depolarized mitochondria. We conclude that caspase activation is of similar importance in As2O3-induced apoptosis in myeloid cell lines as direct mitochondrial targeting and mitochondria are not necessary for caspase activation downstream of mitochondria.  相似文献   
66.
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   
67.
IntroductionA study was performed of the healing rate of teeth subjected to endodontic microsurgery after a minimum follow-up of 5 years with an analysis of the influence of different pre- and postoperative factors on the outcome.MethodsThis was a retrospective study of patients subjected to endodontic microsurgery with the use of mineral trioxide aggregate (MTA) for retrograde filling between January 2011 and December 2015. In patients with multiple treated teeth, only 1 random tooth was selected for the statistical analysis. Clinical and radiographic parameters were used to assess healing. Simple binary logistic regression models were used to analyze the influence of patient age and sex, the type of tooth, prior radiographic lesion size, the presence of a post, the type of restoration, and the apical extent of prior filling of the root canal on the endodontic microsurgery success rate. Two calibrated observers evaluated the periapical radiographs on an independent basis.ResultsA total of 111 patients (63.1% women and 36.9% men) were included in the study. Of the 111 teeth analyzed, 90 were classified as healed (mean healing rate = 81.1%). Patient age and sex, the presence of a post, the type of tooth, the type of restoration, and the apical extent of prior filling of the root canal had no significant impact on the outcome. Large lesions (>5 mm) were associated with a lower healing rate than smaller lesions, although the difference was not significant. Anterior teeth had a significantly higher healing rate (93.8% maxillary and 100% mandibular) than molars (70.8% maxillary and 57.1% mandibular) (P < .05). The differences between the anterior teeth and the molars were statistically significant.ConclusionsThe mean healing rate of teeth subjected to endodontic microsurgery was 81% after 5–9 years of follow-up. The success rate was lower for upper and lower molars than for teeth in the anterior zone, although the sample was small and further studies are needed to establish whether the type of tooth influences the treatment outcome.  相似文献   
68.
69.
《Journal of endodontics》2020,46(2):149-157.e4
IntroductionHealed rates of endodontic microsurgery (EMS) may decrease over time, but research on the long-term outcomes is scarce. The aims of this retrospective cohort study were to evaluate the 5- to 9-year healed and survival rates of EMS, to identify associations between prognostic factors and healing status, and to compare the short-term (1- to 2-year) with long-term (5- to 9-year) outcomes.MethodsOne hundred fifty-one eligible patients (166 teeth) who underwent EMS in 2007–2010 were invited for a follow-up examination. Eighty-three patients (94 teeth) participated in the study. Survival status and reasons for extraction of all teeth were determined, and survival rates were calculated by Kaplan-Meier analyses. Outcomes were determined on the basis of clinical and radiographic findings and associated with potential prognostic variables via multivariate Cox regression analyses.ResultsThirty-two teeth were extracted: 6 because of endodontic failure, 20 for unrelated reasons, and 6 for unknown reasons. Outcomes were categorized as healed and not healed. Multivariate analysis revealed that adjusted hazard ratio for failure was 5.95 times higher (95% confidence interval, 1.54–22.91) for teeth treated with intermediate restorative material than with mineral trioxide aggregate and 3.38 times higher (95% confidence interval, 1.05–10.9) for teeth with no known history of nonsurgical retreatment. Teeth classified as healed in the 1- to 2-year review mostly remained healed at 5- to 9-year review (45/48 teeth); those with uncertain healing had varied outcomes at long-term review.ConclusionsEMS results in high long-term healed (78.3%, 72/92 teeth) and survival (95.2%) rates. Root-end filling material and nonsurgical retreatment before EMS may influence the long-term outcome.  相似文献   
70.
目的 对比研究应用矿物三氧化物凝聚体(mineral trioxide aggragate,MTA)牙髓切断术与Vitapex牙髓摘除术治疗深龋机械性露髓乳磨牙的临床效果。方法 选取2014年6—12月于第四军医大学口腔医院就诊并符合纳入标准的深龋患儿108例,共计患牙224颗。将所有患儿随机均分为牙髓切断组(119颗患牙)和牙髓摘除组(105颗患牙),分别采用MTA牙髓切断术和Vitapex牙髓摘除术进行治疗。术后6、12、18个月随访观察两组治疗效果,并进行治疗成功率评价。结果 随访患者共92例,共计患牙192颗,其中牙髓切断组患牙101颗,牙髓摘除组患牙91颗。术后6、12、18个月牙髓切断组治疗效果均优于牙髓摘除组;比较术后18个月两组治疗成功率发现,牙髓切断组治疗成功率(90.10%)高于牙髓摘除组(79.12%),差异有统计学意义(χ2 = 4.50,P = 0.04)。结论 相较于Vitapex牙髓摘除术,MTA牙髓切断术治疗深龋机械性露髓乳磨牙的短期疗效更好,推荐临床医生应用。  相似文献   
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