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961.
The purpose of this study was to assess the efficacy of alexidine(ALX),alone and combined with N-acetylcysteine(NAC),in eradicating two Enterococcus faecalis strain biofilms.The biofilms of E.faecalis ATCC 29212 and the clinical isolate E.faecalis D1 were grown in the MBEC-high-throughput device for 24 h and were exposed to five twofold dilutions of ALX(2%–0.007 8%)alone and combined with100 mg?mL21NAC,for 1 and 5 min.Eradication was defined as 100%kill of biofilm bacteria.The Student’s t-test was used to compare the efficacy of the associations of the two irrigants.After 1-min contact time,ALX eradicated the biofilms at all concentrations except for 0.007 8%and 0.015 6%–0.007 8%with E.faecalis ATCC 29212 and E.faecalis D1,respectively.Similar results for eradication and concentration were obtained when it was combined with 100 mg?mL21NAC.After 5 min of contact time,ALX alone and combined with NAC eradicated all enterococci biofilms.ALX showed antimicrobial properties against the two E.faecalis strain biofilms tested at very low concentrations,and its combined use with NAC was not seen to enhance its activity.  相似文献   
962.
963.
Background Hyaluronan (HA) is a major component of the extracellular matrix (ECM) with increased synthesis during tissue repair. Tumour necrosis factor‐stimulated gene‐6 (TSG‐6) is known to catalyze the covalent transfer of heavy chains (HC1 and HC2) from inter‐α‐inhibitor (IαI) onto HA, and resultant HC?HA complexes have been implicated in physiological and pathological processes related to remodelling and inflammation. Objective The aims of this study were to determine the expression of HA, TSG‐6 and the IαI polypeptides in unscarred skin, normal scars and keloid scars. Methods Formalin‐fixed paraffin‐embedded sections of unscarred skin, normal scars and keloid scars were prepared from patient samples collected during scar revision surgery. Haematoxylin and eosin, as well as immunofluorescent staining for HA, TSG‐6 and the three polypeptide chains of IαI (i.e. HC1, HC2 and bikunin) were performed. Results All skin types stained positive for TSG‐6, HC1, HC2 and bikunin, associated with keratinocytes, fibroblasts and skin appendages all in close proximity to HA. Keloid lesions showed altered HA organization patterns compared with unscarred skin and normal scars. TSG‐6 staining was significantly more intense in the epidermis compared with the dermis of all sample types. There was a significant reduction in TSG‐6 levels within keloid lesions compared with the dermis of unscarred skin (P = 0.017). Conclusion TSG‐6 is expressed in unscarred skin, where its close association with HA and IαI could give rise to TSG‐6‐mediated HC?HA formation within this tissue. A reduction in the beneficial effects of TSG‐6, caused by diminished protein levels in keloid lesions, could contribute to this abnormal scarring process.  相似文献   
964.
965.
运动前进食不同血糖指数食物对长跑能力的影响   总被引:4,自引:1,他引:3  
目的 :探讨运动前进食不同血糖指数食物对长跑能力的影响。方法 :实验设计采用平衡重复测试法 ,8名男子耐力长跑运动员在间隔期不少于 7天内 ,在隔夜空腹情况下分别进食含相等热量的低血糖指数 [Glycemicindex (GI) ](GI =37)或高GI(GI =77)的碳水化合物 (CHO)食物 (CHO∶1 5g/kg体重 )。 2小时后 ,受试者在水平跑台上进行 2 1km的长跑能力测试。首 5km中 ,受试者以其 70 %VO2 max的速度跑步 ,而其后的 16km ,则可随意选择速度以最短时间完成。结果 :与高GI试验相比 ,所有受试者在进食低GI食物后的跑步时间明显缩短 (98 7± 2 0vs 10 1 5± 2 1min ,P<0 0 1)。整个跑步全程中 ,低GI试验的血糖及血清游离脂肪酸 (FFA)的水平较高GI试验为高。虽然进食高GI食物后两小时的血清胰岛素较高 ,但在运动过程中 ,血清胰岛素、皮质醇、血乳酸水平与低GI试验相比均无显著差异。与高GI试验相比 ,低GI试验中CHO氧化在能量供应上的依赖低 9 5 % ,而脂肪氧化则高 17 9%。结论 :在运动前 2小时进食低血糖指数的CHO食物 ,比提供同等热量的高血糖指数食物能更有效地提高长跑运动的能力。  相似文献   
966.
Fetal hemoglobin induction with butyric acid: efficacy and toxicity   总被引:7,自引:2,他引:5  
Butyric acid induces fetal hemoglobin (HbF), a property of potential therapeutic advantage in patients with disorders of globin chain synthesis. We performed dose escalation studies of this compound in baboons to assess whether clinically significant increases in HbF are achievable, and to define the associated toxicities. Additionally, the effect of butyrate in combination with erythropoietin on HbF induction was assessed. HbF induction in response to butyrate was dependent on the dose and duration of treatment. Doses of butyrate less than 4 g/kg/d were associated with minimal toxicity (hypokalemia) and significant HbF induction in these nonanemic animals, with 1 g/kg/d producing an increase in HbF-containing reticulocytes (F reticulocytes) from 0.9% to 8.7% and an increase in HbF from 0.8% to 1.4%. A dose of 2 g/kg/d resulted in an increase in F reticulocytes from 2.1% to 27.8% and an increase in HbF from 0.7% to 2.2%. Doses of 4 g/kg/d in another animal produced an increase in F reticulocytes from 1% to 21.6% and in HbF from 1.9% to 5.3%. Infusions in excess of 4 g/kg/d were complicated (after a variable amount of time) by a decreased level of alertness (caused by hyperosmolality or butyrate itself) and hematologic toxicity (with declines in reticulocyte, white blood cell, and platelet counts). Prolonged infusions of high doses of butyrate (8 to 10 g/kg/d) were associated with peak F reticulocyte percentages reaching 38% to 64.5% and HbF reaching levels in excess of 20%. These high doses (8 to 10 g/kg/d) were complicated in two animals with a striking and unique neuropathologic picture and, in one animal, multiorgan system failure. Erythropoietin in combination with butyrate, induced F reticulocytosis in an additive manner. We conclude that butyric acid is a strong inducer of HbF, particularly when administered in combination with erythropoietin. As chronic toxicities remain undefined, patients in future clinical trials of this and similar compounds should be monitored closely for evidence of neurologic toxicity.  相似文献   
967.
Objectives The aim of the study was to determine the modifications of the mutational archive in proviral HIV-1 DNA occurring during 24 months of intermittent or continuous highly active antiretroviral therapy (HAART).
Methods The study population included subjects enrolled in the Istituto Superiore di Sanità Pulsed Antiretroviral Therapy (ISS PART) clinical trial. All of these patients were on first-line HAART and had plasma HIV-1 RNA below 50 HIV-1 RNA copies/mL. A genotypic resistance test was performed on HIV-1 DNA extracted from peripheral blood mononuclear cells (PBMC) at baseline and after 24 months of follow-up. Resistance-associated mutations (RAMs) were defined according to the International AIDS Society (IAS) USA classification.
Results Sixty-nine subjects were included in the study [36 enrolled in arm A of the ISS PART (continuous HAART) and 33 enrolled in arm B (intermittent HAART)]. No major modifications of the mutational archive were found in either group after 24 months of follow-up, in terms of both the proportion of subjects with mutations and the total number of mutations.
Conclusions In this patient population, the mutational archive in HIV-1 DNA extracted from PBMC was stable for 24 months, irrespective of HAART modality, whether continuous or intermittent.  相似文献   
968.
969.
970.
Granuloma annulare is a benign, relatively common dermatosis in childhood. The subcutaneous form is rare, and lesions typically occur on the legs, buttocks and scalp. We report a case of a deep granuloma annulare confined to the palms of the hands in a 2-year-old child.  相似文献   
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