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41.
The clinical and histopathological findings in a 40-year-old man with a lacrimal sac tumor are reported. Although the clinical history indicated a lacrimal sac obstruction and recurrent dacryocystitis, the lesion was diagnosed by light microscopy as a squamous cell carcinoma.  相似文献   
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Williams syndrome is a genetic disorder in which visuo-spatial performance is poor. Theorists have claimed that the deficit lies in high-level processing, leaving low-level visual processes intact. We investigated this claim by examining an aspect of low-level processing, perceptual completion, i.e. the ability of this clinical group to perceive illusory Kanizsa squares. We then used event-related potentials to examine neural correlates of perceptual completion. While participants were able to perceive illusory contours, the neural correlates of this apparently normal perception were different from controls. Such differences in low-level visual processes may significantly impact on the development of higher-level visual processes. We conclude that, contrary to earlier claims, there is atypical neural processing during low-level visual perception in Williams syndrome.  相似文献   
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Halit H  de Haan M  Johnson MH 《NeuroImage》2003,19(3):1180-1193
The adult N170 is considered to be an electrophysiological marker of specialised mechanisms for face processing, but little is known about its developmental origin. Previous work has identified two face-sensitive infant ERP components (N290 and P400) (J. Cog. Neurosci. 14 (2002), 199). In the present study, we assessed the specificity (to upright human faces) of these infant components at 3 and 12 months. At 12 months the degree of specificity observed in both components was similar to that seen in the adult N170. In contrast, at 3 months of age the N290 and P400 did not show the same level of specificity for human faces as that observed at 12 months. Our findings suggest that (1) both face-sensitive components increase in their specificity for upright human faces during development, and (2) the adult N170 is not preceded by a single developmental precursor, but rather emerges as a consequence of the integration of two functionally and morphologically distinct components (N290 and P400).  相似文献   
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We report a case of intrauterine Klebsiella pneumoniae infection that resulted in premature rupture of membranes and fetal demise at 20 weeks' gestation in a pregnancy achieved by in vitro fertilization. Postmortem findings included massive panlobar pneumonia, the presence of abundant gram-negative, rod-shaped bacteria within the pulmonary air spaces and the lumen of the gastrointestinal tract, and fetal lung and blood cultures positive for Klebsiella pneumoniae. The placenta showed severe acute chorioamnionitis associated with a brisk fetal inflammatory response (umbilical cord and chorionic plate vasculitis). Marked pancreatic fibrosis was noted, indicative of a preceding necrotizing pancreatitis. In spite of this fulminant histopathologic evidence of intrauterine infection, the infection was clinically silent. This represents, to our knowledge, the 1st reported case of fatal intrauterine Klebsiella pneumoniae infection fully supported by conclusive fetal and placental histopathological evidence.  相似文献   
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PURPOSE: This study was conducted to evaluate the effect of various degrees of diffuse fatty infiltration of the liver on the hepatic artery resistance index. METHODS: One-hundred forty subjects were examined using standard color and spectral Doppler sonography protocols. Fatty infiltration of the liver was identified and graded sonographically. The patients were grouped (n = 35 in each of 4 groups) according to the degree of diffuse fatty infiltration of the liver as follows: normal (group 1), mild (group 2), moderate (group 3), and severe (group 4). The resistance index calculated for each patient was the mean of 3 measurements. Mean resistance index of the hepatic artery was then calculated for each group. RESULTS: The mean resistance index was 0.81 +/- 0.04 for group 1, 0.79 +/- 0.06 for group 2, 0.75 +/- 0.05 for group 3, and 0.73 +/- 0.05 for group 4. We found a statistically significant (p < 0.05) decrease in resistance index when comparing groups 3 and 4 with groups 1 and 2 separately. CONCLUSIONS: Hepatic artery resistance index decreases as the severity of diffuse fatty infiltration increases.  相似文献   
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Transsphenoidal encephaloceles are rare and the transsellar variety is the least common. We present a 1-year-old male patient with transsellar transsphenoidal encephalocele which herniated into the oral cavity through the congenital split palate. The patient was operated on using a combined transcranial and transpalatal approach without mortality or permanent morbidity. Clinical findings, imaging reviews, surgical repair techniques and postoperative morbidity are discussed with the relevant literature. We conclude that repair of a transsphenoidal encephalocele should be coordinated between a team of neurosurgeons and otorhinolaryngologists. Our surgical outcome supports a transcranial approach for the treatment of these difficult lesions, with transpalatal dissection and exposure.  相似文献   
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OBJECTIVE: The purpose of our study was to determine the breast radiation dose during coronary calcium scoring with multidetector computerized tomography (MDCT). We also evaluated the degree of dose reduction by using a bismuth breast shield when performing coronary calcium scoring with MDCT. MATERIALS AND METHODS: The dose reduction achievable by shielding the adult (35 years or older) female breasts was studied in 25 women who underwent coronary calcium scoring with MDCT. All examinations were performed with a 16-MDCT scanner. To compare the shielded versus unshielded breast dose, the examinations were performed with (right breast) and without (left breast) breast shielding in all patients. With this technique the superficial breast doses were calculated. To determine the average glandular breast radiation dose, we imaged an anthropomorphic dosimetric phantom into which calibrated dosimeters were placed to measure the dose to the breast. The phantom was imaged using the same protocol. Radiation doses to the breasts with and without the breast shielding were measured and compared using the Student's t-test. RESULTS: The mean radiation doses with and without the breast shield were 5.71+/-1.1 mGy versus 9.08+/-1.5 mGy, respectively. The breast shield provided a 37.12% decrease in radiation dose to the breast with shielding. The difference between the dose received by the breasts with and without bismuth shielding was significant, with a p-value of less than 0.001. CONCLUSION: The high radiation during MDCT greatly exceeds the recommended doses and should not be underestimated. Bismuth in plane shielding for coronary calcium scoring with MDCT decreased the radiation dose to the breast. We recommend routine use of breast shields in female patients undergoing calcium scoring with MDCT.  相似文献   
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