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71.
超声微泡造影影像学及治疗作用的研究进展 总被引:2,自引:0,他引:2
包裹型气体微泡已经发展为临床应用的超声造影剂.微泡造影剂不仅已广泛用于血池和组织灌注显像,其治疗作用也日渐突显,例如溶栓和作为药物或基因的载体.造影剂微泡的平均直径小于红细胞直径,因而能够自由运行于微循环.微泡能将生物活性物质(例如药物或基因)结合在其内或其外膜表面,并将此物质转运于体内特定组织,例如将抗肿瘤药物转运并结合于特定肿瘤组织.靶向性微泡能将肽段等特定性配体结合于其微泡表面,这种特定性配体可特异性地与血管壁表达的受体相结合,微泡因而在靶组织区域积聚[1]. 相似文献
72.
Brandon JC; Teplick SK; Haskin PH; Sammon JK; Muhr WF; Hofmann AF; Gambescia RA; Zitomer N 《Radiology》1988,166(3):665-667
The authors describe their experience with methyl tertiary butyl ether (MTBE) in a larger series of patients than previously reported in order to acquaint physicians with both its effectiveness for dissolution of common bile duct calculi and the limitations of its use. Ten patients with 13 biliary calculi underwent percutaneous stone dissolution treatment with the experimental cholesterol solvent, MTBE. Three stones completely dissolved within 30 minutes, seven were reduced in size, and three were visibly unaffected. All stones not completely dissolved were easily extracted by means of a stone basket except for one in a patient taken to surgery. Although MTBE perfusion is an effective technique for management of biliary calculi, practitioners should be aware that its use is quite time consuming and its odor difficult to control. 相似文献
73.
JK Gass SK Chan E Rytina DC Greenberg NP Burrows 《Journal of the European Academy of Dermatology and Venereology》2010,24(5):601-603
Background Merkel cell carcinoma (MCC) is a rare malignant cutaneous tumour, the incidence of which is increasing. Second malignancies have been reported to occur with high incidence in these patients. Objectives We report the rate and nature of multiple malignancies in patients with MCC treated over a 10 year period in Addenbrooke’s Hospital in Cambridge, United Kingdom, as well as the temporal relationship of these additional malignancies to the diagnosis of MCC. Results The 27 patients had an approximately equal sex incidence with a median age at diagnosis of 79 years. Seventy percent (n=19) of patients had a second primary malignant tumour; and 7 of these patients had two or more tumours in addition to the MCC. Eighteen patients had additional cutaneous malignancies: melanoma, squamous cell carcinoma and basal cell carcinoma, and 8 patients presented non‐cutaneous malignancy including colorectal, haematological and breast tumours. Of the 28 additional tumours in our patients, half were diagnosed prior to presentation of MCC, 32% within 6 months of diagnosis, and 18% between 6 months and 3 years after diagnosis. Possible reasons for the high rate of additional tumours in this population are discussed. Conclusions Our figures reflect a higher incidence of multiple malignancies in those with Merkel cell tumour than has previously been reported. This has important implications for the care and surveillance of these patients. 相似文献
74.
目的:观察咬合垂直距离改变对无牙颌颞下颌关节紊乱病患者两侧颞颌关节髁状突位置的影响。方法:于1994-01/1997-12选择本院口腔修复门诊收治的无牙颌患者中符合颞下颌关节紊乱病诊断标准,同时垂直距离减低的患者48例。实验方案经医院伦理委员会审批,患者均知情同意。将48例无牙颌颞下颌关节紊乱病患者根据垂直距离减低程度的不同分为3组:减低1.8~6.0mm组18例,减低6.1~10.0mm组20例,减低10.1 ̄14.0mm组10例。通过重新制作一副全口义齿的方法治疗,咬合垂直距离恢复在合适的范围内,3组全口义齿的咬合垂直距离恢复前分别平均为63.4,60.6,54.2mm,恢复后咬合垂直距离分别平均为67.8,68.4,66.4mm,平均抬高4.4,7.8,12.2mm。通过拍摄正中颌位时颞下颌关节薛氏位X射线片测量各组前、后、上关节间隙。结果:垂直距离恢复前,减低1.8~6.0mm组关节后间隙,减低6.1~10.0mm组关节前、后间隙、减低10.1 ̄14.0mm组关节上、后间隙左右侧相比较,差异有显著性意义(P<0.05)。垂直距离恢复后,3组关节间隙左右侧差异无显著性意义。结论:无牙颌咬合垂直距离减低后可以导致两侧髁状突位置发生不对称改变。 相似文献
75.
76.
Thirty-three patients with a variety of disorders of the thoracic aorta (aneurysm, dissection, Marfan syndrome, coarctation/pseudocoarctation, L-transposition, and Takayasu disease) were evaluated with magnetic resonance (MR) imaging. MR imaging delineated the presence and extent of thoracic aortic aneurysms and showed the relationship of the aneurysm to arch vessels; it also demonstrated intimal flaps and individual lumina in types A and B aortic dissection. Dilation of the ascending aorta in Marfan syndrome and focal narrowing of the aorta in coarctation were well visualized. The anteroposterior and side-to-side relationships of the aorta and pulmonary artery in L-transposition were demonstrated, as were aortic wall thickening and branch vessel narrowing in Takayasu arteritis. Initial experience suggests that MR imaging may provide a noninvasive method for evaluating thoracic aortic disease. Limitations include inferior spatial resolution, occasional difficulty in imaging the entire region of interest in one section, lack of signal from calcifications, and inability to monitor critically ill patients. 相似文献
77.
Psoas muscle disorders: MR imaging 总被引:3,自引:0,他引:3
Nineteen patients with evidence of psoas and iliopsoas abnormalities on computed tomographic (CT) scans (12 with metastases, three with lymphoma, two with hematoma, and two with abscess) were examined with magnetic resonance (MR) imaging. The abnormal psoas could be identified on both T1- and T2-weighted spin-echo images, although T2-weighted sequences provided better contrast. The psoas muscle can be affected by one of three mechanisms: total replacement, lateral displacement, or medial displacement. In four patients in whom the CT study showed apparent enlargement of a psoas muscle, subsequent MR imaging examinations demonstrated that the psoas muscle was compressed and displaced laterally by a paraspinal mass. MR images provided better contrast between the normal and abnormal psoas than CT scans in nine cases; MR images were inferior to CT scans in two cases because calcifications (one case) and air bubbles within an abscess (one case) were not detectable. 相似文献
78.
Is ACTH a key to understanding anticonvulsant action? 总被引:2,自引:1,他引:1
ME O'Regan MB MRCP DCH JK Brown MB FRCP DCH 《Developmental medicine and child neurology》1998,40(2):82-89
Adrenocorticotrophin hormone (ACTH) has been used as an anticonvulsant for many years. In this paper, the use of ACTH in 23 children with intractable epilepsies is described. It was found that ACTH worked most effectively when the EEG showed benzodiazepine sensitivity. A mechanism of action of ACTH is proposed. 相似文献
79.
Hepatic metastases studied with MR and CT 总被引:1,自引:0,他引:1
Examinations of the liver using magnetic resonance (MR) and computed tomography (CT) were performed on 50 patients with hepatic metastases. MR and CT were comparable in their ability to detect metastases, which generally appeared hypointense compared with normal liver parenchyma on T1-weighted MR images and hyperintense on T2-weighted images. The MR imaging techniques that were most reliable in detecting metastases were inversion recovery and a relatively T2-weighted, spin-echo technique (TR = 1,500 msec, TE = 60 msec). We conclude that CT, because of its shorter imaging time, greater spatial resolution, and lower cost, should remain the preferred screening test for hepatic metastases. MR imaging should be reserved for patients with equivocal CT findings and for patients in whom there is persistent clinical suspicion of hepatic metastases despite a negative CT examination. 相似文献
80.
To investigate the sodium magnetic resonance (MR) imaging characteristics of acute vasogenic edema, an experimental canine model was developed. Vasogenic edema was produced in the hemisphere of the dogs by the intraarterial infusion of hypertonic mannitol (25%). This solution opens the blood-brain barrier, allowing the influx of water, electrolytes, and proteins into the brain. The main advantage of this model over the established "cold injury" model is the lack of associated brain necrosis. Two patients with chronic vasogenic edema secondary to well-circumscribed meningiomas also underwent MR imaging. The sodium signal was markedly elevated in both clinical and experimental studies of vasogenic edema fluid compared with signal in healthy brain tissue. Extracellular sodium associated with vasogenic edema displayed MR imaging characteristics similar to that of sodium in serum. There was a trend toward a shortened T2 in edema fluid secondary to the presence of serum macromolecules. 相似文献