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In this study, a novel composite bone substitute was implanted in animal models (rats) and their in vivo characteristics were examined. A D,L-lactide and E-caprolactone copolymer (Mw: 80,000; Mn:40,000, and PI:2.00) was synthesized by ring-opening polymerization of the respective dimers using stannous octoate as the catalyst. The final ratio of D,L-lactide to epsilon-caprolactone obtained by 1NMR was 60/40. Hydroxyapatite (HA) powder was loaded in the copolymer. The HA/copolymer ratio was 60/40 (w/w). These composites were easily shaped by hand. Animal tests were performed on mature wistar rats (n=30). Defects were created on the proximal, the thickest part of the femur. The bone defects of the first group were filled with polymer/HA composite, the second group filled with only HA and the third group was left empty. Histologic examination of bone tissues showed new bone formation around the yellow-green polymer/HA composite material in the first group of animals whereas no evidence of new bone growth was observed in other groups.  相似文献   
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Journal of Public Health - Because an increasing number of patients travel internationally to seek medical care, Turkey offers comprehensive and outstanding services under extraordinary conditions...  相似文献   
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OBJECTIVE: Accurate prenatal diagnosis of congenital diaphragmatic hernia is important for perinatal planning and potential fetal surgery. We describe the application and usefulness of helical CT amniography in the evaluation of suspected congenital diaphragmatic hernia in three fetuses. CONCLUSION: Helical CT amniography is an efficient means for evaluation of congenital diaphragmatic hernia. Accurate diagnosis was made in all three patients.  相似文献   
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OBJEctive: The oxidant-antioxidant balance plays an important role in the pathogenesis of COPD. The aim of the present study was to evaluate the effects of exercise, as an oxidative stress factor on the oxidant-antioxidant balance and to investigate whether short-term antioxidant treatment affects lipid peroxidation products. METHODOLOGY: Twenty-one stable COPD patients and 10 control subjects were included in the study. Symptom-limited exercise tests were performed by all subjects. Blood was collected before and 1 h after exercise in control subjects and before, 1 and 3 h after exercise in COPD patients, for analysis of malondialdehyde (MDA), reduced glutathione (GSH) and vitamin E (VE) levels. VE and vitamin C treatments were added to the regular bronchodilator therapy in 10 COPD patients for 1 month. After the treatment period, an exercise test was performed and blood was collected again for MDA, GSH and VE levels. RESULTS: Baseline GSH and VE levels were significantly lower in the COPD group when compared with the control subjects. There was no statistically significant difference in MDA levels between the two groups. In the COPD group, MDA levels 3 h after exercise were significantly higher than at baseline. In contrast there were no significant differences in MDA, VE and GSH levels in the control group after exercise. VE and MDA levels increased significantly after exercise in COPD patients but there was no difference in GSH levels. Baseline exercise time was significantly lower in the COPD group than in the controls. In 10 COPD patients who were given antioxidant therapy, their exercise time increased significantly and there was no increase in MDA and VE levels after the repeated exercise test. CONCLUSIONS: Antioxidant levels were significantly lower in COPD patients than in control subjects. In these patients, exercise results in more significant oxidative stress and lipid peroxidation than in control subjects and antioxidant therapy may decrease lipid peroxidation following exercise and improve exercise capacity.  相似文献   
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Objectives

Confirmation of the endotracheal tube placement (CoETP) has the utmost importance in the management of an airway. Visualization of tracheal rings or carina with a fiber-optical bronchoscope (FOB) has considered to be a reliable method for the CoETP. However, FOB is expensive, time-consuming, and not always practical. Inexpensive endoscopic USB-cameras were shown to aid intubation successfully and reliably. On the other hand, there have been no studies investigating their use for the CoETP. Tracheal ultrasonography (TUS) is also a new, inexpensive and widely available alternative. A cadaver study has planned to evaluate the diagnostic utility of TUS and a USB-camera.

Methods

This study was conducted in the Anatomy Lab of a University on a fresh frozen female cadaver. Three senior Emergency Physicians have intubated the cadaver, and performed TUS or USB-endoscopy. We have prepared a randomized intubation list (n = 96) in three blocks (3 times 32) as to include equal number of esophageal and tracheal intubations (48 for each). Each EP is performed all three interventions (intubation, TUS and USB-endoscopy) in consecutive blocks of 32 intubations, in turn. The position of the tube has been verified from a 2 cm wide ostium on the proximal trachea.

Results

In this study, all intubations (n = 96, 100%) were correctly identified as tracheal or esophageal with both TUS and USB-camera. Both the sensitivity and specificity of TUS and USB-endoscopy for the CoETP were 100.0%.

Conclusion

The perfect accuracy of TUS and USB-endoscopy, have placed those techniques in a unique position as an alternative in resource-poor situations.  相似文献   
8.
Statement of problemLaser sintering is commonly used for fabricating metal-ceramic restorations. The layer thickness of the sintering process may affect restoration adaptation. However, limited information is available regarding its impact.PurposeThe purpose of this in vitro study was to compare the marginal and internal adaptation of laser-sintered cobalt-chromium single crown frameworks sintered with layer thicknesses of 25 and 50 μm.Material and methodsThirty resin dies that represented prepared single molar abutment teeth were prepared by using a 3-dimensional printer and were divided into 3 groups (n=10) according to the method used for fabricating metal frameworks: group C, metal frameworks fabricated by using the lost-wax method (control); group L25, metal frameworks fabricated by using direct metal laser melting with a layer thickness of 25 μm; and group L50, metal frameworks fabricated by using direct metal laser melting with a layer thickness of 50 μm. After fabricating the metal frameworks, 15 vertical marginal discrepancy measurements were made in each axial region (mesial, distal, buccal, and lingual) using a stereomicroscope. Next, all the specimens were sectioned from the midline, and 5 internal discrepancy measurements were made in each internal region (inner marginal, axial, and occlusal). The data were analyzed statistically by using 1-way ANOVA, the Tukey honestly significant difference, and Tamhane T2 tests (α=.05).ResultsThe highest marginal and internal discrepancy values were obtained for metal frameworks in group C, and these values were significantly different (P<.001) from those obtained for metal frameworks in the other 2 groups. No significant difference was observed in the marginal and internal discrepancy values of metal frameworks in groups L25 and L50.ConclusionsThese results indicate that layer thickness does not affect the adaptation of laser-sintered metal frameworks, yet both sintering parameters yielded significantly lower mean marginal discrepancy values than the cast group.  相似文献   
9.

Background:

The hepatitis B virus is an important healthcare problem. According to current clinical practice, a liver biopsy is required for the diagnosis and treatment of chronic liver disease. However, a liver biopsy is an invasive, inconvenient procedure, which requires an expert pathologist opinion. Therefore requirement of biochemical tests, which are considered to indicate hepatic fibrosis and may be repeated easily, increases gradually today.

Objectives:

This study evaluated the correlation between hepatic fibrosis and routine laboratory values in patients with chronic hepatitis B.

Patients and Methods:

The files of 456 patients with CHB (chronic hepatitis B) who were referred to the infectious diseases and clinical microbiology clinic between January 2009 and March 2012 were screened retrospectively. Liver biopsy samples were examined according to Ishak scoring. Laboratory parameters and histopathology reports were recorded, and correlations between the fibrosis grade and laboratory parameters were analyzed.

Results:

There were 320 male and 136 female patients, with a mean age 36.7 ± 12.1 years. According to liver biopsy results, a low fibrosis score (stage 0-2) was detected in 281 patients (61.6%), and a high fibrosis score (stage 3-5) was detected in 175 patients (38.4%). Patients with a high fibrosis score had significantly higher ALT (alanine amino transferase), AST (aspartate aminotransferase), and HBV-DNA values and a significantly lower platelet count compared with those with a low fibrosis score (P = 0.001, 0.001, 0.025, and 0.001, respectively). A positive correlation was detected between the fibrosis score and age, BMI, HAI, ALT, and AST values, and a negative correlation was detected between the fibrosis score and albumin and platelet counts. In the regression analysis performed to evaluate the factors associated with high-stage fibrosis, fibrosis was determined to be associated with thrombosis, ALT, and gender. The results of the regression analysis demonstrated that the risk of fibrosis was 4.6 fold higher in men.

Conclusions:

According to the results obtained in our study, advanced age, higher BMI, AST, ALT, and HBV-DNA levels, and low albumin and platelet levels are correlated with advanced fibrosis in patients with CHB.  相似文献   
10.
The benefits of taking of aspirin, clopidogrel, and warfarin in relation to cardiovascular mortality and re-hospitalization in chronic heart failure (HF) patients have been called into question. We examined the outcomes (cardiac mortality and/or HF re-hospitalization) in patients discharged from our hospital between January 2003 and July 2009 after hospitalization for chronic decompensated HF. Of 580 HF patients (mean age, 63?±?13?years; mean ejection fraction, 26?±?9%, 63% with coronary disease and 37% without coronary disease), 207 patients (36%) died due to cardiovascular reasons, and 313 (54%) required HF re-hospitalization for decompensated HF during a 39?±?14?month follow-up period. 101 (17%) patients were taking clopidogrel during enrollment in the study. When comparing patients who were on clopidogrel treatment with those who were not, clopidogrel was found to have a beneficial effect on cardiac mortality (27 vs. 38%, P?=?0.04). In conclusion, in this observational prospective study, patients who used clopidogrel showed decreased cardiac mortality [HR, 0.566 (95% CI 0.332-0.964), P?=?0.036] compared to patients who did not take clopidogrel. Clopidogrel had a beneficial effect on the survival of chronic HF patients in the long term.  相似文献   
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