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91.
Rhabdomyolysis ranges from an asymptomatic illness with elevated creatine kinase levels to a life-threatening condition associated with extreme elevations in creatine kinase, electrolyte imbalances, acute renal failure, and disseminated intravascular coagulation. The most common causes are crush injury, overexertion, alcohol abuse, certain medicines, and toxic substances. A number of electrolyte abnormalities and endocrinopathies, including hypothyroidism, thyrotoxicosis, diabetic ketoacidosis, nonketotic hyperosmolar state, and hyperaldosteronism, cause rhabdomyolysis. Rhabdomyolysis and acute renal failure are unusual manifestations of pheochromocytoma. There are a few case reports with pheochromocytoma presenting rhabdomyolysis and acute renal failure. Herein, we report a case with pheochromocytoma crisis presenting with rhabdomyolysis and acute renal failure.  相似文献   
92.
Purpose: Urinary stones are common and can be diagnosed with computed tomography (CT) easily. In this study, we aimed to specify the opacity characteristics of various types of calcified foci that develop through the urinary system by using an image analysis program. With this method, we try to differentiate the calculi from the non-calculous opacities and also we aimed to present how to identify the characteristic features of renal and ureteral calcules. Materials and methods: We obtained the CT studies of the subjects (n?=?48, mean age?=?41 years) by using a dual source CT imaging system. We grouped the calculi detected in the dual-energy CT sections as renal (n?=?40) or ureteric (n?=?45) based on their locations. Other radio-opaque structures that were identified outside but within close proximity of the urinary tract were recorded as calculi “mimickers”. We used ImageJ program for morphological analysis. All the acquired data were analyzed statistically. Results: According to thorough morphological parameters, there were statistically significant differences in the angle and Feret angle values between calculi and mimickers (p?p?=?0.003) and kidney (p?=?0.001) stones. Conclusions: Computer-based morphologic parameters can be used simply to differentiate between calcular and noncalcular densities on CT and also between renal and ureteric stones.  相似文献   
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94.

Introduction

The purpose of this study was to evaluate the fracture strength of roots instrumented with the Self-Adjusting File (SAF; ReDent-Nova, Ra’anana, Israel) and the ProTaper system (Dentsply Maillefer, Ballaigues, Switzerland) and filled with the cold lateral compaction technique.

Methods

In total, 50 mandibular premolar teeth were sectioned at or below the cementoenamel junction to obtain roots 13 mm in length. The roots were balanced with respect to buccolingual-mesiodistal diameters and weight. They were distributed into 4 experimental groups and 1 control group (n = 10): no instrumentation (control group), instrumentation with ProTaper rotary files but no filling (PT), instrumentation with ProTaper rotary files and filling with cold lateral compaction (PT filling), instrumentation with SAF but no filling (SAF), and instrumentation with SAF and filling with cold lateral compaction (SAF filling). AH Plus sealer (Dentsply DeTrey, Konstanz, Germany) was used along with gutta-percha points. One week later, a vertical load was applied to the specimen’s canal until fracture occurred. Data were statistically analyzed using 1-way analysis of variance (P = .05).

Results

The mean fracture load was 244 ± 51 N for the control group, 226 ± 21 N for the PT, 242 ± 45 N for PT filling, 233 ± 14 N for the SAF, and 271 ± 44 N for SAF filling. However, the differences were not statistically significant (P > .05).

Conclusions

Instrumentation with the SAF or the ProTaper rotary system did not change the fracture strength of standardized roots with respect to cross-sectional diameter and weight.  相似文献   
95.

Introduction

We compared the effects of 6 different rotary systems on transportation, canal curvature, centering ratio, surface area, and volumetric changes of curved mesial root canals of mandibular molar via cone-beam computed tomographic (CBCT) imaging.

Methods

Mesiobuccal root canals of 120 mandibular first molars with an angle of curvature ranging from 20°–40° were divided into 6 groups of 20 canals. Based on CBCT images taken before instrumentation, the groups were balanced with respect to the angle and radius of canal curvature. Root canals were shaped with the following systems with an apical size of 25: OneShape (OS) (MicroMega, Besancon, France), ProTaper Universal (PU) F2 (Dentsply Maillefer, Ballaigues, Switzerland), ProTaper Next X2 (Dentsply Maillefer), Reciproc (R) R25 (VDW, Munich, Germany), Twisted File Adaptive (TFA) SM2 (SybronEndo, Orange, CA), and WaveOne primary (Dentsply Tulsa Dental Specialties, Tulsa, OK). After root canal preparation, changes were assessed with CBCT imaging. The significance level was set at P = .05.

Results

The R system removed a significantly higher amount of dentin than the OS, PU, and TFA systems (P < .05). There was no significant difference among the 6 groups in transportation, canal curvature, changes of surface area, and centering ratio after instrumentation.

Conclusions

The 6 different file systems straightened root canal curvature similarly and produced similar canal transportation in the preparation of mesial canals of mandibular molars. R instrumentation exhibited superior performance compared with the OS, TFA, and PU systems with respect to volumetric change.  相似文献   
96.
OBJECTIVES:Subclinical atherosclerosis has been recently detected in adolescents with a family history of premature atherosclerosis. However, no studies in the literature have assessed the cardiac autonomic functions of these adolescents. The aim of this study was to evaluate the cardiac autonomic functions of adolescents with a family history of premature atherosclerosis compared with those of age- and gender-matched adolescents without a family history of atherosclerosis.METHOD:We evaluated the cardiac autonomic functions of 36 adolescents with a family history of premature atherosclerosis (Group 1) and compared them with those of 31 age- and gender-matched adolescents whose parents did not have premature atherosclerosis (Group 2). Twenty-four-hour time domain (standard deviation of all normal sinus RR intervals [SDNN], standard deviation of the mean of normal RR intervals in each 5-minute segment [SDANN], root-mean-square differences in successive RR intervals) and frequency domain (very low frequency, low frequency, high frequency, low frequency/high frequency) parameters of heart rate variability were used for the evaluation of cardiac autonomic functions.RESULTS:There were no differences in the time and frequency domain parameters of heart rate variability between the two groups. Heart rate was negatively correlated with SDNN (r = -0.278, p = 0.035), while age was significantly correlated with root-mean-square differences in successive RR intervals, high frequency, low frequency and low frequency/high frequency (r = -0.264, -0.370, 0.265 and 0.374, respectively; p<0.05 for all).CONCLUSION:We found that the cardiac autonomic functions of adolescents with a family history of premature atherosclerosis were not different compared with those of adolescents without a positive family history of premature atherosclerosis. It appears that subclinical atherosclerosis does not reach a critical value such that it can alter cardiac autonomic functions in adolescence.  相似文献   
97.

Background

To our knowledge, no study so far investigated the importance of post‐procedural frontal QRS‐T angle f(QRS‐T) in ST segment elevation myocardial infarction (STEMI). The aim of our study was to investigate the role of baseline and post‐procedural f(QRS‐T) angles for determining high risk STEMI patients, and the success of reperfusion.

Methods

A total of 248 patients with first acute STEMI that underwent primary percutaneous coronary intervention (pPCI) or thrombolytic therapy (TT) between 2013 and 2014 were included in this study. Baseline f(QRS‐T) angle was defined as the angle which measured from the first ECG at the time of hospital admission. Post‐procedural (QRS‐T) angle was defined according to the treatment strategy as follows: the angle which measured from the post‐PCI ECG in patients treated with pPCI; the angle which measured from the ECG taken 90 min after onset of therapy in patients treated with TT.

Results

The baseline (101.9° ± 48.0 vs. 72.1° ± 49.1, p = 0.014) and post‐procedural f(QRS‐T) angles (95.7° ± 48.1 vs. 58.1° ± 47.1, p = 0.002) were significantly higher in patients who developed in‐hospital mortality than the patients who did not develop in‐hospital mortality. Also, f(QRS‐T) angle measured at 90 min was significantly lower in patients with successful thrombolysis group compared to failed thrombolysis group (53.2° ± 42.8 vs. 77.3° ± 52.9, p = 0.033), whereas baseline f(QRS‐T) angle was similar between two groups (78.6° ± 53.4 vs. 78.9° ± 54.0, p = 0.976). Multivariate analysis showed that post‐procedural f(QRS‐T) angle ≥89.6° (odds ratio: 3.541, 95% confidence interval: 1.235–10.154, p = 0.019), but not baseline f(QRS‐T) angle, was independent predictor of in‐hospital mortality.

Conclusion

f(QRS‐T) angle may be used as a beneficial tool for determining high risk patients in acute STEMI. Unlike previous studies, we showed for the first time that that post‐procedural f(QRS‐T) can predict in‐hospital mortality and TT failure.
  相似文献   
98.
99.
100.
Papillary lesions have a broad spectrum of appearances on magnetic resonance imaging (MRI ). The purpose of this study was to evaluate whether apparent diffusion coefficient (ADC ) values of papillary lesions can be used to characterize lesion as benign or malignant. This retrospective study included 29 papillary lesions. Diagnostic values of dynamic contrast‐enhanced MRI (DCE‐MRI), DWI ‐ADC , and DCE ‐MRI plus DWI ‐ADC were separately calculated. The malignant papillary lesions (0.744×10?3 mm2/s) exhibited significantly lower mean ADC values than the benign lesions (1.339×10?3 mm2/s). Addition of DWI to standard DCE ‐MRI provided 100% sensitivity. We hypothesized that this combination may prevent unnecessary excisional biopsies.  相似文献   
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