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21.

Objective

To investigate the relations between the vegetation cover and occurrence of cutaneous leishmaniasis (CL) in Golestan province during 2010-2012.

Methods

Data of monthly CL incidence and remote sensing normalized difference vegetation index (NDVI) of moderate resolution imaging spectroradiometer sensor were used in the study. Pearson''s correlation analysis was conducted to examine the type and strength of relationships between the spatially averaged NDVI variables (i.e. minimum, maximum and mean NDVI values) and CL incidence in township level. Spearman rank correlation was carried out to explain associations between the monthly CL incidence and NDVI variables at 0, 1, 2, 3 and 4 months lagged periods. Locations of CL cases at village level were geocoded and compared with frequency of CL cases in each NDVI-derived vegetation categories.

Results

Pearson''s analysis revealed significant associations between the NDVI variables and CL incidence at the township level (P<0.05). Results of Spearman analysis indicated that the highest correlations between NDVI variables and monthly CL incidence were established when the NDVI time-series lagged the CL incidence series NDVI variables. Purely spatial analysis demonstrated that despite majority of cases occurred at partially-vegetated areas, the possibility of CL occurrence was higher in bare soil areas by taking into account area of each vegetation zones.

Conclusions

lack or low vegetation cover is a major determinant of CL frequencies in Golestan province. The decrease of the mean vegetation density in townships is accompanied by increase of CL occurrence and vice versa.  相似文献   
22.

Introduction

The aim of this in vivo study was to evaluate the influence of apical periodontitis (AP) on the accuracy of Dentaport ZX (J Morita, Kyoto, Japan), Raypex 5 (VDW, Munich, Germany), and i-Root (S-Denti, Seoul, Korea) electronic root canal length measurement devices (ERCLMDs).

Methods

Thirty-two single-rooted teeth scheduled for extraction, consisting of 16 teeth with AP and 16 teeth with normal periapex (NP), were selected. The access cavity was prepared, and the coronal portion of the canal was flared. The electronic working length (EWL) was determined by each ERCLMD according to each manufacturer's instructions. Each tooth was extracted, and the actual working length (AWL) was determined by inserting a size 15 K-file until the tip could be seen at a position tangential to the major foramen and then 0.5 mm was subtracted from the measurement. The distance from the file tip (EWL) to the point 0.5 mm coronal to the major foramen (AWL) was calculated. Data were analyzed using the nonparametric Fisher exact test and the chi-square test. Statistical significance was set at P < .05.

Results

The accuracies of Dentaport ZX, Raypex 5, and i-Root within ±0.5 mm in the AP group were 93.8%, 81.3%, and 75.0%; they were 93.3%, 86.7%, and 73.3% in the NP group, respectively. There were no significant differences between the accuracy of each device in the 2 groups (P > .05). Considering the 2 groups of AP and NP, there were no statistically significant differences in the accuracy of the ERCLMDs (P > .05).

Conclusions

The presence of AP did not influence the accuracy of ERCLMDs.  相似文献   
23.
BACKGROUND: Topiramate and sodium valporate are anticonvulsants, demonstrated to be effective as monotherapy for migraine prevention in placebo-controlled trials. OBJECTIVES: To compare the relative efficacy of topiramate and sodium valporate in the prevention of migraine. PATIENTS AND METHODS: A 24-week, randomized, double-blind, crossover, clinical trial was conducted from October 2003 to September 2004. A total of 64 patients with migraine headache, aged 14 to 57 years, were randomly allocated to the 2 treatment groups. The first group received topiramate (25 mg daily increment over 1 week to 50 mg) for a total of 2 months. The second group received sodium valporate (200 mg daily increment over 1 week to 400 mg) for 2 months. Response to treatment was assessed at 0, 1, 8, 16, and 24 weeks after start of therapy. RESULTS: Topiramate appeared to be equivalent in efficacy and safety to sodium valporate. A significant decrease in duration, monthly frequency, and intensity of headache occurred in both groups. Of the 32 patients treated with sodium valporate, the mean standard deviation (SD) of monthly migraine frequency decreased from 5.4 (2.5) to 4.0 (2.8) episode per month, headache intensity from 7.7 (1.2) to 5.8 (1.7) by visual analog scale (VAS), and headache duration from 21.3 (14.6) to 12.3 (10.7) hours (P < .001). Correspondingly, in the 32 patients treated with topiramate, the mean SD of monthly headache frequency decreased from 5.4 (2.0) to 3.2 (1.9) per month, headache intensity from 6.9 (1.2) to 3.7 (1.3), and headache duration from 17.3 (8.4) to 3.9 (2.7) hours (P < .001). CONCLUSION: This study demonstrates that treatment with topiramate and sodium valporate both significantly reduce migraine headache. This effect of topiramate and sodium valporate has previously been shown to reduce migraine headache, and we postulate that treatment with topiramate and sodium valporate may have a similar benefit.  相似文献   
24.
INTRODUCTION: The role of metalloelements in tissue maintenance, function and response to injury offer a new approach to decreasing and/or treating radiation injury. We investigated the roles of CuL(2)SO(4), [MnL(2)O](2)Cl(4)(H(2)O)(2) and [(VL(2)O)(VL(2)H(2)O)]Cl(6) complexes (L=2-methylaminopyridine) of SOD-mimetic activities, in ameliorating the radiation-induced oxidative stress and alterations in some biochemical parameters in liver, kidney, spleen and brain in pretreated female rats exposed to gamma-irradiation. METHODS: Both untreated-rats and rats treated with the above complexes were subjected to whole-body gamma-irradiation (6 Gy). 5'-Nucleotidase (5'-NT), acetylcholinesterase (AChE), adenosne triphosphatase (ATPase), superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GSSG-R) were assessed as well as liver DNA and RNA contents and total protein concentration were estimated in tissue homogenates of the above organs. The same parameters were assessed in non-irradiated treated rats and normal control rats. Results were compared to irradiated non-treated and normal control rats. RESULTS: Pretreatment of gamma-irradiated rats with Mn(IV) or V(IV) complex produced a significant decrease in liver 5'-NT activity compared to the corresponding value of the untreated irradiated rats. In contrast, liver DNA and RNA contents and brain AChE and ATPase activities were significantly increased in irradiated rat group pre-treated with these metal complexes. Cu II, Mn IV or V IV complex inoculation prior to irradiation of normal rats exhibited a significant increase in SOD, CAT, GSSG-R activities and protein content of liver, kidney, spleen and brain homogenates compared with that of the untreated irradiated rats. The treatment of non-irradiated rats with these complexes produced a highly significant increase in mean activities of SOD and CAT, with no changes in other parameters vs. controls. CONCLUSIONS: Cu(II), Mn(IV) and V(IV) 2-methylaminopyridine complexes offer a physiological approach to ameliorate the radiation-induced biochemical alterations. In addition, they provide sufficient protection against radiation injury of radiosensitive tissues.  相似文献   
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Abstract Purpose: Performing laparoscopic nephrectomy in the setting of previous renal surgery may be challenging and associated with a higher complication rate. We conducted this study to assess the feasibility and safety of laparoscopic nephrectomy among patients with a history of ipsilateral renal surgery. Patients and Methods: We reviewed the chart of 193 patients who underwent transperitoneal laparoscopic nephrectomy for nonfunctioning kidney between April 2007 and March 2011. The study population was divided into two groups: Group 1 comprised 37 patients with a history of ipsilateral renal surgery, and Group 2 consisted of 156 patients with no history of previous renal surgery. Results: Baseline characteristics and preoperative variables were similar in both groups. Mean operative time, complication rate, and hospital stay were comparable between the two groups. A nonstatistically significant trend toward a higher transfusion rate was noted in Group 1 patients. The operation was converted to open nephrectomy in 1 (2.7%) and 3 (1.9%) patients of Groups 1 and 2, respectively (P=.765). Conclusions: Laparoscopic nephrectomy of the nonfunctioning kidney is a feasible and safe procedure in the setting of previous renal surgery and is not associated with a significant increase in operative time and complication rate compared with patients with no prior ipsilateral renal surgery.  相似文献   
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