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991.
Carolyn?I?Baker Christopher?P?Barrozo Margaret?AK?Ryan Lisa?A?Pearse Kevin?L?RussellEmail author 《BMC infectious diseases》2005,5(1):38
Background
In December 2001, a fatal case of pneumococcal meningitis in a Marine Corps recruit was identified. As pneumococcal vaccine usage in recruit populations is being considered, an investigation was initiated into the causative serotype. 相似文献992.
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The purpose of the present paper was to evaluate the utility of perfusion MRI in cerebral gliomas showing imperceptible contrast enhancement on conventional MRI, and to evaluate the relationships of perfusion MRI and magnetic resonance (MR) spectroscopic results in these tumours. Twenty‐two patients with histopathologically proven cerebral gliomas and showing insignificant contrast enhancement on conventional MR were included in the present study. All patients underwent perfusion MRI and MR spectroscopy on a 1.5‐T MR system. Significant differences of the relative cerebral blood volume (rCBV) values and the choline : creatine ratios were noted between low‐grade and anaplastic gliomas (P < 0.01). Good correlation was found between the rCBV values and the choline : creatine values (y = 0. 532x + 1.5643; r = 0.67). Perfusion MRI can be a useful tool in assessing the histopathological grade of non‐contrast‐enhancing cerebral gliomas. Along with MR spectroscopic imaging it can serve as an important technique for preoperative characterization of such gliomas, so that accurate targeting by stereotactic biopsies is possible. 相似文献
996.
N Geetha BM Hussain TV Ajitkumar AK Ittiyavirah M Krishnan Nair 《Journal of Medical Imaging and Radiation Oncology》1998,42(3):252-253
Metastasis to the spleen from carcinomas is a rare event. A case is described here of a 28-year-old man with germ cell tumour of the testis in whom splenic metastasis was demonstrated radiologically. The lesion resolved with chemotherapy and the patient has been in complete remission for 1 year. 相似文献
997.
998.
M Aribandi M Gulati D Behera KM Das NE Chandra S Suri 《Journal of Medical Imaging and Radiation Oncology》1997,41(4):367-370
Twenty-five patients with active pulmonary tuberculosis were prospectively studied with CT. Three major parenchymal patterns were noted. The nodular opacities pattern was seen in all cases. Confluent consolidation was seen in 37% of patients and consolidation with associated loss of volume (CWALV) was seen in 69% of patients. High-resolution CT (HRCT) features of bronchogenic spread included (i) a centrilobular nodule or a branching linear structure (92.3%); (ii) bronchial wall thickening (61.5%); (iii) a‘tree in bud’appearance (92.3%); and (iv) poorly marginated 5-8 mm nodules (61.5%). Most of the patterns showed satellite lesions in the form of small nodules or peripheral areas of increased attenuation. Cavitation was most common in CWALV lesions. Bronchiectasis was a common accompaniment (81.3%), and its occurrence paralleled the distribution of parenchymal lesions. Associated pleural thickening was noted in half the cases. To conclude, distinctive parenchymal changes were noted with CT in cases of pulmonary tuberculosis, which may suggest the diagnosis in the appropriate clinical setting. 相似文献
999.
Time trends on the association of maternal age, birth order, and marital status with the risk of sudden infant death syndrome (SIDS) and non-SIDS deaths in Norway were analysed: 2356 postperinatal SIDS deaths and 4069 postperinatal non-SIDS deaths were ascertained during 1967-93. The SIDS incidence was 1.25 per 1000 in 1967, reached a peak of 2.69 in 1988, and fell to 1.22 in 1990 after the initiation of an intervention programme to avoid prone sleeping. In the entire period, young maternal age, high birth order, and unmarried motherhood were associated with SIDS. The adverse effects of young maternal age and high birth order increased continuously with time. From 1967-71 to 1990-93, the relative risk for maternal age < 20 years v maternal age 25-29 changed from 2.5 (95% confidence interval 2.0 to 3.2) to 7.0 (95% CI 4.2 to 11.9) (p < 0.0001), and for birth order 4+ nu birth order 1 from 3.2 (95% CI 2.5 to 4.2) to 14.4 (95% CI 8.3 to 24.9) (p < 0.0001). Effects on non-SIDS deaths were far weaker and no secular trends were observed. The strong association of young maternal age, high birth order, and marital status in SIDS, but not in non-SIDS, provides evidence that SIDS is an epidemiological entity. The increasing effects of young maternal age and high birth order, which continued after the sudden drop in the SIDS rate in 1990, suggest that further efforts to prevent SIDS should be aimed particularly at identifying causal mechanisms in high risk groups. 相似文献
1000.
MUSTAFA LENK ALPAY ELIKER DURSUN ALEHAN GüLENDAM KOAK ENCAN
ZME 《Pediatrics international》1997,39(5):570-577
Tachyarrhythmias are common rhythm disturbances in infants and children. Despite the availability of diagnostic criteria arrhythmias are sometimes commonly misdiagnosed. Recent reports suggest that an endogenous purine nucleoside, adenosine, has a diagnostic effect in narrow QRS complex tachycardias, in addition to terminating supraventricular tachycardia involving the atrioventricular node. This report reviews the authors' experience with the use of adenosine for diagnosis of narrow and wide complex tachyarrhythmias in children. Adenosine was administered to 43 patients with several types of tachyarrhythmias (mean age, 8.3 ± 5.24 years). Nineteen patients had structural or acquired heart disease. Of the 43 patients there were 28 (65%) several different types of narrow QRS complex tachycardia and 14 (33%) ventricular arrhythmias. One patient (2%) had long QT. Adenosine terminated supraventricular tachycardia, in 11 of 12 patients (92%), ventricular tachycardia in five of eight patients (63%), and transiently terminated premature ventricular contractions in two of six patients (33%). The diagnostic ability of adenosine was perfect in eight supraventricular tachycardia. In these eight cases the tachycardia mechanism was unclear before the administration of adenosine, which demonstrated three cases of sinus tachycardia, three of atrial flutter, one of atrial fibrillation and one of atrial fibrilloflutter. Confirmation of the primary diagnosis by adenosine was perfect in five tachyarrhythmias including three cases of atrial flutter, one of atrial fibrillation and one of ectopic atrial tachycardia. The average effective dose of adenosine was 212 μg/kg (range, 100–400 μg/kg). There were no serious side-effects except transient dyspnea, chest pain and flushing. These findings demonstrate adenosine to be helpful and safe in the diagnosis of tachyarrhythmias. 相似文献