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排序方式: 共有531条查询结果,搜索用时 15 毫秒
31.
替硝唑软膏的研制与临床应用 总被引:9,自引:0,他引:9
目的:研究替硝唑软膏,并应用于临床。方法:参照同类制剂,确定最优组方和制备方法,采用紫外分光光度法测定含量,用比较法进行临床疗效观察。结果:制剂制备简单,含量测定方法简便,结果可靠,经临床应用牙周炎、牙龈炎患者62例,总有效率95.3%。结论:本品是治疗牙周炎、牙龈炎的理想制剂,值得推广应用。 相似文献
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Brain tumors: MR imaging with gadolinium-DTPA 总被引:8,自引:0,他引:8
Felix R; Schorner W; Laniado M; Niendorf HP; Claussen C; Fiegler W; Speck U 《Radiology》1985,156(3):681-688
Magnetic resonance (MR) imaging was performed on 40 patients with intracranial tumors, before and after intravenous administration of gadolinium-DTPA (Gd-DTPA). Precontrast studies included a comprehensive protocol of spin-echo sequences. Tumors were visualized on precontrast images either directly or indirectly by anatomic distortion caused by the mass. However, differentiation of the tumor from adjacent tissues was possible in only 17 of 40 cases. Delineation of the tumor was best on precontrast, T2-weighted images. After administration of Gd-DTPA (0.1 mmol/kg), increased signal intensity from the tumor was observed in all patients. The localized increase in signal intensity in the tumor considerably improved the tumor delineation in 36 of 40 patients. Whereas most of the meningiomas, neuromas, and adenomas could be delineated prior to administration of contrast material if appropriate pulse sequences were applied, glioblastomas and intracranial metastases required Gd-DTPA administration for diagnostically sufficient tumor display. 相似文献
34.
Electroneutral cation-chloride cotransporters are abundantly expressed in the brain and are involved in the regulation of the intracellular Cl(-) concentration and thus gamma-aminobutyric acid-dependent inhibition of neuronal excitability. As yet there is little evidence whether or not Na(+)-K(+)-2Cl(-) or K(+)-Cl(-) cotransporters are involved in neuronal hyperexcitability and death in cerebral ischemia. In this study, by measuring propidium iodide staining in organotypic hippocampal slice cultures from young rats and population spike recovery in acutely isolated hippocampal slices from adult rats after a hypoxic/hypoglycemic insult, we were able to assess if cation-chloride cotransport inhibitors reduce neuronal injury. The Na(+)-K(+)-2Cl(-) cotransport inhibitor bumetanide in the range of 1-10 microM reduced neuronal damage in the slice cultures by 25%, but did not affect population spike recovery in acutely isolated slices. In contrast the K(+)-Cl(-) cotransport inhibitor [(dihydroindenyl)oxy] alkanoic acid (DIOA, 100 microM) significantly diminished the restitution of the population spikes from 33% before to 8% after hypoxia/hypoglycemia and increased the damage in the slice cultures by 60%. Consequently, our data suggest that the Na(+)-K(+)-2Cl(-) cotransporter may contribute to neuronal injury and that the activity of the K(+)-Cl(-) cotransporters is an intrinsic protective mechanism of neurons against ischemic damage. 相似文献
35.
Virtual colon dissection with CT colonography compared with axial interpretation and conventional colonoscopy: preliminary results 总被引:8,自引:0,他引:8
Hoppe H Quattropani C Spreng A Mattich J Netzer P Dinkel HP 《AJR. American journal of roentgenology》2004,182(5):1151-1158
OBJECTIVE: The aim of this study was to determine whether a new virtual colon dissection 3D visualization technique for CT colonography has a shorter analysis time and better sensitivity for detection of colonic polyps than interpretation of axial CT images. SUBJECTS AND METHODS. CT colonography was performed in 22 patients using 4-MDCT followed by conventional colonoscopy on the same day. The CT colonography data sets were analyzed by virtual colon dissection, which virtually bisects and unfolds the colon along its longitudinal axis to inspect the inner colonic surface for polyps. The same CT data sets were independently evaluated using axial interpretation. All data sets were independently interpreted by two radiologists in a blinded manner. RESULTS: Conventional colonoscopy revealed 31 colonic lesions in 20 patients. Twenty two of the lesions were smaller than 10 mm; nine were 10 mm or larger. Two of the original 22 patients were excluded, one because of residual stool and fluid and the other because of an impassable stenosing rectal wall cancer. For virtual colon dissection, the per-lesion sensitivity was 42% for observer 1 and 68% for observer 2; for axial interpretation, the respective sensitivities were 48% and 61%. For polyps 10 mm or larger, the respective sensitivities were 67% and 89% for virtual colon dissection and 89% and 100% for axial interpretation. The average time for reconstruction and analysis of virtual colon dissection was 36.8 min versus 29.2 min for axial images. Virtual colon dissection was feasible in both the supine and the prone positions in 45.5% of colonic segments, in either the supine or the prone position in 24.5%, and in neither position in 30% of segments. CONCLUSION: Although virtual colon dissection may facilitate detection of colonic polyps in isolated cases, its detection rate is not superior to axial interpretation, which is mainly attributable to failed rendering of insufficiently distended colonic segments or regions with residual feces. Virtual colon dissection is also the more time-consuming of the two procedures. With further improvement of path-finding and image segmentation, however, virtual colon dissection has the potential to be a useful interpretation tool for CT colonography. 相似文献
36.
Levy JI Welker-Hood LK Clougherty JE Dodson RE Steinbach S Hynes HP 《Environmental health : a global access science source》2004,3(1):13
Background
Children in urban public housing are at high risk for asthma, given elevated environmental and social exposures and suboptimal medical care. For a multifactorial disease like asthma, design of intervention studies can be influenced by the relative prevalence of key risk factors. To better understand risk factors for asthma morbidity in the context of an environmental intervention study, we conducted a detailed baseline evaluation of 78 children (aged 4–17 years) from three public housing developments in Boston. 相似文献37.
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E Dinkel S Orth M Dittrich H Schulte-Wissermann 《AJR. American journal of roentgenology》1986,146(4):775-780
Increase in renal volume and asymmetry in kidney size determined by sonography proved to be a valuable diagnostic criterion for differentiation between infections of the upper and lower urinary tract in 175 children: acute bacterial interstitial nephritis (79) and lower urinary tract infection (96). Kidney volume in acute pyelonephritis increased to an average of 175% of normal. In 71% of cases, affected kidneys showed an enlargement of at least 2 SD when compared with a group of 325 children without kidney pathology. Most impressive kidney enlargement was seen during the first year of life. In 50% of cases, acute pyelonephritis caused a bilateral increase in renal size and/or distinct volume asymmetry. Kidneys of patients with lower urinary tract infections had a mean volume of 99.68% and a physiologic volume asymmetry comparable to normal kidneys. 相似文献
40.
Tracheobronchomegaly: clinical aspects and radiological features 总被引:1,自引:0,他引:1
Tracheobronchomegaly is a rare--probably congenital--disorder. Its clinical appearance is non-specific. The diagnosis is made by radiological methods. This paper describes the typical features in early and advanced stages and outlines the diagnostic approach. 相似文献