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11.
Signal intensity (SI) changes of pancreatic parenchyma were evaluated after intravenous administration of secretin using T2-weighted single-shot spin-echo echo-planar imaging (EPI) to assess this method as a magnetic resonance (MR) test of pancreatic exocrine function. Nine volunteers were studied with serial single-shot EPI of the pancreas for 15 minutes after the injection of secretin or saline. The normal pattern of pancreatic SI change was demonstrated after intravenous injection of secretin, a single peak at 3-4 minutes in the head, body, and tail, followed by a gradual decrease in SI. Saline injection did not induce a significant SI change. There was no statistical difference in the peak contrast ratios (first mean, 1.21-1.25, vs. second mean, 1.18-1.22) and peak times (first mean, 3.2-3.7 minutes, vs. second mean, 3.1-3.6) in a repeat study. By evaluating the pattern of time-response curves obtained from serial T2-weighted EPI after secretin injection, pancreatic exocrine function may be directly assessed at the level of the head, body, and tail.  相似文献   
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Nakamura H  Kawasaki N  Taguchi M  Kabasawa K 《Cancer》2005,103(9):1865-1873
BACKGROUND: Prognostic implications of overexpression of the HER-2 gene in nonsmall cell lung carcinoma (NSCLC) are a matter of controversy. Many conflicting results have been reported from different laboratories. METHODS: A metaanalysis of published studies was performed for this quantitative review of the effects of HER-2 overexpression on survival among patients with NSCLC. Of 44 articles initially selected, 20 articles fulfilled eligibility criteria. DerSimonian-Laird random effects analysis was used to estimate the effects of HER-2 overexpression on survival differences (the survival rate among patients without HER-2 overexpression minus the survival rate among patients with HER-2 overexpression) at endpoints of 1 years, 3 years, and 5 years after resection of NSCLC. RESULTS: In total, 2579 patients were included in the final analysis. Overall, HER-2 positivity differed according to histologic type and included 38% of patients with adenocarcinoma, 16% of patients with squamous cell carcinoma, and 18% of patients with large cell carcinoma (P < 0.0001). The combined survival differences in patients with NSCLC at 1 year, 3 years, and 5 years, respectively, were 2.7% (95% confidence interval [95% CI], 1.3-6.7%; P = 0.1787), 15.2% (95% CI, 5.8-24.5%; P = 0.0015), and 16.4% (95% CI, 7.9-14.8%; P = 0.0001), suggesting significant poorer survival at 3 years and 5 years among patients with HER-2 overexpression. In patients with adenocarcinoma, the combined survival difference at 5 years was 26.0% (95% CI, 16.0-36.1%; P < 0.0001), suggesting a particularly strong survival impact for HER-2 overexpression. CONCLUSIONS: A significant, unfavorable prognostic effect of HER-2 overexpression in NSCLC was evident from the metaanalysis. However, because several studies that found no significant difference were excluded by the current eligibility criteria, caution is needed in interpreting the results.  相似文献   
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STUDY OBJECTIVE: The aim of this study is to investigate the probability of visual detection of fade in response to train-of-four (TOF) stimulation, double-burst stimulation3,3 (DBS(3,3)), or DBS(3,2) at the eyelid in comparison to that at the thumb. DESIGN: This is a randomized single-blinded study. SETTING: The study took place at the University hospital. PATIENTS AND MEASUREMENTS: Sixty adult patients underwent general anesthesia. INTERVENTIONS AND MEASUREMENTS: Patients were randomly divided into either the eyelid group (n = 30) or the thumb group (n = 30). In the eyelid group, at the varying degrees of neuromuscular block caused by vecuronium, TOF, DBS(3,3), or DBS(3,2) were given at the temporal branch of the facial nerve, and the probability of visual detection of fade in response to TOF, DBS(3,3), or DBS(3,2) was determined at the eyelid. Similarly, in the thumb group, the probability of visual detection of fade in response to TOF, DBS(3,3), or DBS(3,2) was examined at the thumb. MAIN RESULTS: When the true TOF ratios were 0 to 0.60, the probability of detection of TOF fade in the eyelid group was significantly lower than in the thumb group (P < .05). At the true TOF ratios of 0.31 to 0.70, the probability of visual detection of DBS(3,3) fade in the eyelid group was significantly less than in the thumb group (P < .05). When the true TOF ratios were 0.81 to 1.00, the probability of detection of DBS(3,2) fade in the eyelid group was significantly higher than in the thumb group (P < .05). CONCLUSION: The probability of visual detection of fade in response to TOF or DBS(3,3) is lower at the eyelid than the thumb. In contrast, DBS(3,2) fade tends to be seen more frequently at the eyelid than at the thumb.  相似文献   
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OBJECTIVE: The aims of this study were to investigate the influence of dietary zinc intake on physical growth and to clarify effects of dietary factors in preschool children. METHODS: Food consumption of 30 children aged 5-6 years (15 boys and 15 girls) was surveyed using a weighing dietary method for three consecutive days each in spring and autumn. Daily nutrient intakes were calculated using the Standard Tables of Food Composition in Japan Fifth Revised Edition, 2000. The heights and weights were also measured in each season. They were classified into low, middle and high zinc intake groups, and their physical growth and dietary factors were compared. RESULTS: The average zinc intake was 6.4 +/- 1.1 mg/day in all children, which met the demands of the Japanese RDA (6.0 mg/day). Classification was a low zinc intake group (5.4 +/- 0.5 mg/day), a middle group (6.2 +/- 0.3 mg/day), and a high group (7.7 +/- 0.6 mg/day). The lower zinc intake group showed lower heights and weights, but all children who participated demonstrated increase during the 5 months from spring to autumn. In particular, increase in height in the low zinc intake group was the highest among the three groups. Regarding each food item contribution for the zinc intake, rice (20.53%), meat (16.28%), milk (15.57%), eggs (7.45%), and soybeans (6.87%) were the highest 5 of 19 items, accounting for 66.7% of the total. Zinc intake from vegetable foods (55%) was more than that from animal foods (45%). Intake of total energy, nutrients, and some food groups positively associated with average zinc intake. However, energy intake from confectionery in the lowest zinc intake group was highest among the three groups. CONCLUSION: Estimation of zinc intake of Japanese children using a weighing dietary method has suggested that even a relatively low dietary value might not significantly affect the physical growth of children. Rice is the main source and reduction of zinc intake from regular meals might be related to high consumption of confectionery.  相似文献   
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Inoue T  Ogasawara K  Konno H  Ogawa A  Kabasawa H 《Neurologia medico-chirurgica》2003,43(9):421-5; discussion 426
Diffusion tensor (DT) imaging provides quantitative information about the magnitude and the directionality (anisotropy) of water diffusion in vivo and can detect pathologic changes in brain ischemia. This study tried to detect ischemic brain damage using DT imaging in patients with symptomatic chronic major cerebral artery occlusive disease. DT imaging was performed using a 3.0 Tesla magnetic resonance (MR) scanner in 50 patients with unilateral internal carotid artery or middle cerebral artery stenosis or occlusion, who had no obvious infarct lesions on conventional MR imaging. Thirty-three patients underwent DT imaging before and after vascular reconstruction surgery. Fractional anisotropy (FA) was calculated in the middle cerebral artery territory. Preoperative FA values in the ipsilateral side were significantly lower than those in the contralateral side. After surgery, the FA value was significantly increased. DT imaging may indicate ischemic brain damage, not visualized by conventional MR imaging, in patients with major cerebral artery occlusive disease.  相似文献   
18.
Diffusion tensor imaging (DTI), a magnetic resonance (MR) technique to analyze diffusion anisotropy of the brain, is able to demonstrate subtle white matter anatomy. Tractography is expected to be a unique, non-invasive tool to provide more pertinent insights into brain structure and orientation not accessible by conventional MRI. In this report, preliminary experiences of visualization of the corticospinal tract using tractography are described. DTI of the brain was performed in 5 normal volunteers using single-shot echo-planar imaging, then tractography was generated by our original software. We determined that the two-region-of-interest (ROI) method is superior to the one-ROI method.  相似文献   
19.
In vivo, water diffusion displays directionality due to presence of complex microstructural barriers in tissue. The extent of directionality of water diffusion can be expressed as a fractional anisotropy (FA) value, using diffusion tensor MR imaging (DTI). The aim of this study was to determine whether FA values indicate microstructures in astrocytic tumors. We performed DTI in 31 patients with astrocytic tumor, and measured the FA values of tumor and normal brain regions prior to CT-guided stereotactic biopsy. After biopsy, FA values were compared to assess the cellularity and vascularity of tumor tissue. Although mean FA values trended to differ among histological types, all mean tumor FA values were lower than those of normal brain regions. Positive correlation was observed between FA values and both cellularity (r = 0.65, p < 0.05) and vascularity (r = 0.45, p < 0.05). We had hypothesized that the FA value of an astrocytic tumor would be determined by a balance between factors increasing the directionality of water diffusion, such as high cellularity and/or vascularity, and factors decreasing the directionality of water diffusion, such as fiber destruction. However, our results suggest that the FA values of glioblastoma, anaplastic astrocytoma, diffuse astrocytoma and pilocytic astrocytoma are largely affected by cellularity and/or vascularity, whereas that of gliomatosis cerebri are largely affected by the preservation of nerve fibers. Measurement of FA value using DTI will allow prediction of histological characteristics such as cellularity, vascularity and/or fiber structure in astrocytic tumors.  相似文献   
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