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21.
Localized proton magnetic resonance spectroscopy of a cerebellar tumor in a two-year-old child 总被引:1,自引:0,他引:1
B. Wilken G. Helms H. J. Christen J. Bhnk J. Frahm F. Hanefeld 《Child's nervous system》1996,12(10):626-629
Noninvasive localized proton magnetic resonance spectroscopy (MRS) was used for differential diagnosis of a focal brain lesion in a 2.5-year-old girl. The clinical signs were a mild head tilt and neck pain. Magnetic resonance imaging (MRI) revealed a lesion in the right hemisphere of the cerebellum, but its nature remained obscure. In this lesion quantitative determinations of cerebral metabolites by fully relaxed, short-echo-time proton MRS revealed markedly lowered N-acetylaspartate (NAA) and pronounced elevations of choline-containing compounds (Cho) and myo-inositol (Ins), whereas metabolite concentrations in cortical gray matter and white matter were within normal ranges. The metabolite pattern of the lesion indicated loss of vital neuroaxonal tissue (low NAA) and enhanced glial proliferation (high Cho and Ins), which, together with the MRI morphology, suggested a brain tumor. The diagnosis was established by neurosurgical exploration and total extirpation of the tumor. Histology confirmed an astrocytoma (WHO II). After 2 weeks' recovery the child was discharged with no neurological signs. 相似文献
22.
Changes on serial assessments of brain MRI lesion load are used for monitoring therapeutic efficacy in patients with multiple
sclerosis (MS). We assessed the accuracy and reliability of conventional spin-echo (CSE) and fast spin-echo (FSE) sequences
for measurement of lesion volume using a semiautomated contour technique. Cranial CSE and FSE examinations of 18 patients
with secondary progressive MS were studied. The mean lesion load was slightly higher with the CSE sequence (p = 0.002). Intraobserver
variability was significantly higher for FSE than for CSE, according to both the coefficient of variation between two measurements
(mean 2.48 % and 1.35 % respectively, p < 0.05) and back-transformed 95 % limits of agreement (1.005–1.060 for FSE; 0.988–1.019
for CSE). Although FSE sequences are quicker and the total lesion volume measurements are similar to those obtained with CSE,
the poorer reproducibility raises doubts about the use of FSE to replace CSE in clinical trials.
Received: 26 March 1996 Accepted: 4 April 1996 相似文献
23.
A. Heinig S. H. Heywang-Köbrunner P. Viehweg D. Lampe J. Buchmann R. P. Spielmann 《Der Radiologe》1997,37(9):710-717
Summary
Early recognition of recurrence and work-up of clinically indeterminate lesions may be impaired after reconstruction with
silicone implants due to superimposition of the implant or to scarring. This study was undertaken to evaluate the use of contrast-enhanced
MRI in patients with silicone implant after breast cancer. Contrast-enhanded MRI was offered to 169 patients. Comparative
two- to three-view mammography was also performed in 169 patients, as well as comparative sonography in 144 patients. Conventional
imaging and clinical examination detected only 8/13 recurrences, whereas 12/13 were detected by MRI. One recurrence had been
visible as a strongly enhancing 2-mm dot in a previous examination (2 years before), but was not called. It was therefore
counted as false negative. In addition, multicentricity was detected by MRI alone in two of three cases. MRI correctly diagnosed
scar tissue in all cases with indeterminate findings. However, due to false-positive calls caused by enhancing granulomas
specificity could not be improved. Contrast-enhanded MRI allowed decisive additional information in our study group and improved
the sensitivity significantly (concerning all diagnoses). Contrast-enhanded MRI is recommended in patients with diagnostic
problems or high risk of recurrence after silicone implants.
相似文献
24.
Summary Two contrasting cases of cervical intramedullary cavernous angioma in young female patients are reported. One patient had a 3-year course of step-wise progressive tetraparesis; at each of the five events intramedullary bleeding from a cryptic vascular malformation at C6–7 level was diagnosed by MRI. The other patient presented with one episode which led to MRI diagnosis of a vascular malformation at the C2 level. Both patients eventually underwent complete surgical excision of the angioma with subsequent steady improvement of the neurological deficit. 相似文献
25.
椎动脉型颈椎病的影像学诊断 总被引:2,自引:0,他引:2
本文描述了椎动脉型颈椎病的概念及发病机制 ,并对该病的各种影像学检查的主要表现及优缺点进行了综述。 相似文献
26.
27.
邢建枝 《华北煤炭医学院学报》2002,4(6):793-793
我院自 1997~ 2 0 0 1年以来 ,CT扫描诊断检查重症颅脑外伤 (GCS评分 3~ 8分 ) 16 4例 ,其中 16 1例平稳度过扫描期 ,3例因伤势严重在扫描过程中呼吸心跳停止 ,经抢救无效死亡。1 临床资料 16 4例重症颅脑损伤中 ,单纯颅内血肿 6 3例占 38% ;血肿伴脑挫裂伤 38例占 2 3% 相似文献
28.
肿瘤样钙质沉着症临床病理分析 总被引:3,自引:0,他引:3
目的 加深对肿瘤样钙质沉着症 (TC)临床病理特征的认识 ,提高确诊率。方法 分析 9例TC的临床、影像学、组织病理学资料。结果 TC临床诊断误诊率较高 ,9例患者中仅有 1例术前诊断正确 ,余者分别误诊为良性肿瘤 4例、异物 3例、恶性肿瘤 1例 ;而且 9例钙化区均具有典型的影像学和组织病理学特征。结论 在诊断TC过程中 ,只要注意X线摄片检查或进行病理组织活检 ,完全可以避免漏诊或误诊 ,必要时可行特殊染色或偏振光显微镜检查 相似文献
29.
目的 探讨儿童颈椎间盘钙化症的影像表现及诊断价值,并提高对本病的认识。方法 回顾分析16例儿童颈椎钙化性椎间盘病的影像表现。结果 16例患均行颈椎平片检查,5例行CT扫描并作了三维重建,8例行MRI检查。16例平片均显示了椎间盘钙化灶,均为单发,CT平扫加三维重建显示4例钙化呈卵圆形,1例钙化为不规则形。MRI检查不仅显示了椎间盘内改变还清晰显示了病变相邻椎体边缘信号改变,在T1、T2加权像上呈低信号。结论 平片检查可以显示椎间盘钙化;CT平扫加三维重建能清晰显示了钙化灶的大小、形态;MRI检查在显示受累椎体及周围组织的改变方面明显优于CT和平片。 相似文献
30.