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1.
《Immunity》2022,55(9):1594-1608.e6
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2.
In the present study, effect of exposure of bisphenol A (BPA) and combined exposure of BPA + HSD has been investigated on the glucose homeostasis and associated renal complications in Drosophila. Exposure of 1.0 mM BPA alone induced type 2 diabetes like condition (T2D) in adult male D. melanogaster via oxidative stress. Elevated TGF-β signaling was evident by increased expression of baboon (babo) in BPA exposed organism that stimulated the modulation of extracellular matrix (ECM) component collagen IV resulting in the fibrosis of the Malpighian tubules (MTs). Combined exposure of BPA + HSD (high sucrose diet) resulted in the increased magnitude of T2D and MTs dysfunction parameters. Taken together, the study illustrates that BPA has diabetogenic potential in exposed Drosophila that caused adverse effects on their MTs and combined exposure with BPA and HSD could aggravate the renal tubular dysfunction. The study further suggests the use of Drosophila model to study the environmental chemicals induced diabetes mediated renal dysfunction.  相似文献   
3.
Ochratoxin A (OTA) is a mycotoxin that mainly causes nephrotoxicity. The single nephrotoxicity of OTA exposure on glomeruli or renal tubule had been well documented, however, the comparison toxicity between it is still unclear. Here, C57BL/6 mice and two types of nephrocyte were treated with concentration-gradient OTA to explore its differentiation nephrotoxicity. Results showed that OTA induced nephrotoxicity in vivo and in vitro, manifested as the deteriorative kidney function in mice and the cut-down cell viability in nephrocyte. Besides, results of murine kidney pathological section and IC50 of two types nephrocyte indicated that OTA-induced toxicity in renal tubule was higher than its in glomeruli. In addition, OTA exposure induced autophagy signaling differentiation expression. It revealed that autophagy was implicated in OTA-induced differential nephrotoxicity in glomeruli and renal tubule. Altogether, we proved that OTA induces a differentiation nephrotoxicity in glomeruli and renal tubule, and it is related to autophagy differential regulation.  相似文献   
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AIM: To evaluate the efficacy of 0.5%, 2.5% and 5.25% sodium hypochlorite (NaOCl) as intracanal irrigants associated with hand and rotary instrumentation techniques against Enterococcus faecalis within root canals and dentinal tubules. METHODOLOGY: A total of 180 extracted human premolar teeth were infected for 21 days with E. faecalis. The specimens were divided into 12 groups, as follows: group 1: 5.25% NaOCl + Hybrid technique (Valdrighi et al. 1998); group 2: 5.25% NaOCl + nickel-titanium (NiTi) rotary technique 4 mm shorter than the apex (by FOP-UNICAMP); group 3: 5, 25% NaOCl + NiTi rotary technique (Hero 642); group 4: 2.5% NaOCl +Hybrid technique; group 5: 2.5% NaOCl + NiTi rotary technique 4 mm shorter than the apex; group 6: 2.5% NaOCl + NiTi rotary technique (Hero 642); group 7: 0.5% NaOCl + Hybrid technique; group 8: 0.5% NaOCl + NiTi rotary technique 4 mm shorter than the apex; group 9: 0.5% NaOCl + NiTi rotary technique (Hero 642); group 10: sterile saline solution + Hybrid technique; group 11: sterile saline solution + NiTi rotary technique 4 mm shorter than the apex; group 12: sterile saline solution + NiTi rotary technique (Hero 642). Canals were sampled before and after preparation. After serial dilution, samples were plated onto brain heart infusion (BHI) agar, and the colony forming units (CFU) that were grown were counted. The teeth were sectioned into three thirds and dentine chips were removed from the canals with conical burs. The samples obtained with each bur were immediately collected into test tubes containing BHI broth, and were incubated at 37 degrees C and plated onto BHI agar. The CFU were counted and analysed. RESULTS: At all depths and thirds of the root canals and for all techniques used, 5.25% NaOCl was shown to be the most effective irrigant solution tested when dentinal tubules were analysed, followed by 2.5% NaOCl. No differences among concentrations in cleaning the canals were found. CONCLUSIONS: Especially at higher concentrations, NaOCl, was able to disinfect the dentinal tubules, independent of the canal preparation technique used.  相似文献   
6.
AIM: The aim of this laboratory study was to evaluate the ability of calcium hydroxide (CH), CH/iodine-potassium iodide (IKI) and electrophoretically activated copper to kill bacteria in dentinal tubules. METHODOLOGY: In an in vitro model of dentinal tubule infection, 42 cylindrical root specimens, prepared from freshly extracted bovine teeth were used. After removal of the smear layer, intracanal dentinal tubules were infected with Enterococcus faecalis for 3 weeks. CH alone or preparations of CH with copper or IKI were placed in the root canal for 1 week. In specimens containing copper/CH, an electrophoretic current(5 mA/5 min) was applied using two electrodes follow-ing placement of the medicament in the canal. Powder dentine samples obtained from the canal wall using ISO sizes: 025, 027, 029, 031 and 033 burs were examined for the presence of viable bacteria by inoculating agar plates and counting colony forming units (cfu). RESULTS: A significant difference was found between the experimental groups and the positive control group. CH and CH/IKI significantly (P < 0.001)reduced bacterial viability in dentinal tubules to a depth of 200 microm. Specimens with CH/IKI had significantly fewer viable bacteria than CH alone in tubules between the depths of 200-500 microm. Treatment with CH/copper and electrophoresis was most effective: specimens showed no viable bacteria in dentinal tubules to a depth of 500 microm from the root-canal space. CONCLUSIONS: IKI or electrophoretically activated copper additives can significantly improve the antibacterial properties of CH in dentinal tubules.  相似文献   
7.

Introduction

The purpose of this study was to evaluate the antimicrobial activity on Enterococcus faecalis biofilms in dentin canals of short-term and long-term exposure to different endodontic disinfecting solutions by using a dentin infection model and confocal laser scanning microscopy.

Methods

Dentinal tubules in semi-cylindrical dentin blocks were filled with E. faecalis by centrifugation and incubated to form 1-day-old and 3-week-old biofilms. The young and mature biofilms in dentin were subjected to sterile water, 2% chlorhexidine, 2% sodium hypochlorite (NaOCl), and 6% NaOCl for 3, 10, and 30 minutes. After treatments, the proportion of bacteria killed by the disinfectants was analyzed by confocal laser scanning microscopy by using LIVE/DEAD bacterial viability stain.

Results

The proportion of killed bacteria was lower after 3 minutes than after 10 and 30 minutes of exposure to the disinfecting agents (P < .05). The killing of bacteria in the E. faecalis biofilms was fastest during the first 3 minutes and slowed down greatly after 10 minutes. Six percent NaOCl was the most effective antibacterial solution against both the 1-day-old and 3-week-old biofilms (P < .05). No significant difference in bacterial killing was detected between 2% chlorhexidine and 2% NaOCl (P > .05). Significantly more cells were killed in young biofilms than in old biofilms in all groups (P < .05).

Conclusions

The killing of bacteria in infected dentin by disinfecting solutions is time-dependent. However, little additional killing is obtained after the first 10 minutes of exposure.  相似文献   
8.
??Abstract??Objective To evaluate the the sealing effects and abrasive resistance of ClinproTM XT Varnish and Oravive through scanning electron microscope ??SEM??. Methods Totally 48 freshly extracted human premolars were selected?? prepared into dentin discs?? and randomly divided into 3 groups ??group A?? control group?? group B?? ClinproTM XT Varnish group??group C?? Oravive group??. ClinproTM XT Varnish and Oravive were applied respectively on the exposed dentin surfaces of the B and C group in accordance with operating manual. Eight teeth of the B and C group were respectively selected for toothbrush abrasion test. Then an observation was made on the surface and the section plane by scanning election microscope and quantitative analysis was made with Image-Pro Plus 6.0. Results Both of the two desensitizers could occlude the dentinal surface?? and dentinal tubule area and the relative area of the two groups had no significant difference ??P > 0.05??. The two desensitizers could penetrate into the dentinal tubules at a certain depth?? but the penetration depth in group B was larger than that in group C ??P < 0.05???? after the toothbrush abrasion test?? the sealing effect in group B was markedly superior to that in group C ??P < 0.05??. Conclusion ClinproTM XT Varnish performs better than Oravive in sealing effect and abrasion resistance.  相似文献   
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10.
目的研究氟对体外培养的大鼠肾小管上皮细胞凋亡的影响。方法取新生Wistar大鼠肾皮质,制备细胞悬液,传代培养。给予不同浓度的氟化钠(40、80、160μmol/L)处理培养细胞48h后,用Hoechst33342/PI双荧光活染法检测细胞凋亡情况。结果倒置显微镜下发现培养细胞出现细胞碎片明显增多。Hoechst33342/PI双荧光活染法染色检测发现坏死细胞增多。紫外光激发后,40μmol/L NaF处理组出现凋亡细胞,80μmol/L NaF处理组凋亡细胞增多,160μmol/L NaF处理组凋亡细胞明显增多。绿色光激发后,发现80μmol/L NaF处理组出现染色质凝集的晚期凋亡细胞和染色质不凝集的死亡细胞,160μmol/L NaF处理组晚期凋亡细胞较以上各组明显增多。低、中、高氟浓度组凋亡率分别为15.0%、32.4%和62.2%,即随氟浓度的提高,凋亡细胞百分比增加。结论不同浓度的氟均可诱导大鼠肾小管上皮细胞凋亡,随着氟化钠浓度的增加,凋亡细胞增多。  相似文献   
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