全文获取类型
收费全文 | 811篇 |
免费 | 127篇 |
国内免费 | 46篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 26篇 |
妇产科学 | 9篇 |
基础医学 | 136篇 |
口腔科学 | 16篇 |
临床医学 | 119篇 |
内科学 | 183篇 |
皮肤病学 | 18篇 |
神经病学 | 39篇 |
特种医学 | 169篇 |
外科学 | 86篇 |
综合类 | 20篇 |
预防医学 | 63篇 |
眼科学 | 3篇 |
药学 | 58篇 |
肿瘤学 | 34篇 |
出版年
2021年 | 8篇 |
2020年 | 4篇 |
2019年 | 5篇 |
2016年 | 9篇 |
2015年 | 18篇 |
2014年 | 13篇 |
2013年 | 17篇 |
2012年 | 22篇 |
2011年 | 24篇 |
2010年 | 11篇 |
2009年 | 15篇 |
2008年 | 25篇 |
2007年 | 52篇 |
2006年 | 14篇 |
2005年 | 28篇 |
2004年 | 17篇 |
2003年 | 22篇 |
2002年 | 18篇 |
2001年 | 19篇 |
2000年 | 17篇 |
1999年 | 30篇 |
1998年 | 34篇 |
1997年 | 40篇 |
1996年 | 36篇 |
1995年 | 33篇 |
1994年 | 24篇 |
1993年 | 27篇 |
1992年 | 30篇 |
1991年 | 23篇 |
1990年 | 19篇 |
1989年 | 29篇 |
1988年 | 35篇 |
1987年 | 20篇 |
1986年 | 25篇 |
1985年 | 29篇 |
1984年 | 12篇 |
1983年 | 22篇 |
1982年 | 12篇 |
1981年 | 10篇 |
1980年 | 13篇 |
1979年 | 9篇 |
1978年 | 13篇 |
1977年 | 20篇 |
1976年 | 14篇 |
1975年 | 10篇 |
1974年 | 9篇 |
1972年 | 4篇 |
1971年 | 6篇 |
1969年 | 4篇 |
1967年 | 3篇 |
排序方式: 共有984条查询结果,搜索用时 15 毫秒
1.
Laurie Lovett Novak Jonathan Wanderer David A. Owens Daniel Fabbri Julian Z. Genkins Thomas A. Lasko 《Applied clinical informatics》2021,12(1):164
Background The data visualization literature asserts that the details of the optimal data display must be tailored to the specific task, the background of the user, and the characteristics of the data. The general organizing principle of a concept-oriented display is known to be useful for many tasks and data types. Objectives In this project, we used general principles of data visualization and a co-design process to produce a clinical display tailored to a specific cognitive task, chosen from the anesthesia domain, but with clear generalizability to other clinical tasks. To support the work of the anesthesia-in-charge (AIC) our task was, for a given day, to depict the acuity level and complexity of each patient in the collection of those that will be operated on the following day. The AIC uses this information to optimally allocate anesthesia staff and providers across operating rooms. Methods We used a co-design process to collaborate with participants who work in the AIC role. We conducted two in-depth interviews with AICs and engaged them in subsequent input on iterative design solutions. Results Through a co-design process, we found (1) the need to carefully match the level of detail in the display to the level required by the clinical task, (2) the impedance caused by irrelevant information on the screen such as icons relevant only to other tasks, and (3) the desire for a specific but optional trajectory of increasingly detailed textual summaries. Conclusion This study reports a real-world clinical informatics development project that engaged users as co-designers. Our process led to the user-preferred design of a single binary flag to identify the subset of patients needing further investigation, and then a trajectory of increasingly detailed, text-based abstractions for each patient that can be displayed when more information is needed. 相似文献
2.
3.
J Bommer T Weinreich D H Lovett R Bouillon E Ritz D Gemsa 《Nephrology, dialysis, transplantation》1990,5(3):208-213
Loading of tissue macrophages with dialysis-tubing-derived particles may occur during chronic haemodialysis. Previous studies have demonstrated that these particle-laden macrophages release significant quantities of prostaglandins. In these experiments, the effects of dialysis-tubing-particle loading on the release of the central inflammatory mediator, interleukin 1 (IL 1), was examined. Rats received daily injections of silicone or polyvinylchloride (PVC) particles, and were compared to animals given saline alone. The silicone and PVC groups received a total of 3 x 10(9) particles over a 4-week period. Non-stimulated peritoneal macrophages from control animals released a median of 4.1 (range 1.2-10.3) U IL 1 per 10(6) cells. In contrast, macrophages from silicone- and PVC-loaded animals spontaneously released high levels of IL 1 (median 21.8; range 10-36.7) and 94 (range 36-336) U per 10(6) cells respectively). Following in vitro stimulation with bacterial lipopolysaccharide (LPS), peritoneal macrophages from silicone- and PVC-treated animals released large amounts of IL 1 (median 538 (range 359-2017) U and median 653 (range 326-1134) U per 10(6) cells, respectively) as compared to LPS-stimulated macrophages from control animals (median 332 (range 130-306) U per 10(6) cells]. Zymosan or LPS stimulation of splenic cells from silicone- and PVC-loaded animals also secreted increased quantities of IL 1 as compared to controls. The chronic loading of tissue macrophages in dialysis patients with tubing-derived particles may result in augmented release of IL 1, with subsequent activation of inflammatory processes. 相似文献
4.
5.
6.
Technical and biological factors in disease-free survival after hepatic resection for colorectal cancer metastases. 总被引:18,自引:0,他引:18
B Cady M D Stone W V McDermott R L Jenkins A Bothe P T Lavin E J Lovett G D Steele 《Archives of surgery (Chicago, Ill. : 1960)》1992,127(5):561-8; discussion 568-9
Careful patient selection for hepatic resection of colorectal cancer metastases is essential to improve current poor results. Carcinoembryonic antigen level and number of metastases were significant preoperative prognostic indicators of 5-year disease-free survival in patients selected clinically for hepatic surgery. Surgical margin, weight of hepatic tissue resected, carcinoembryonic antigen level, and flow cytometry were significant postoperative prognostic indicators. Patients with a carcinoembryonic antigen level less than 200 ng/mL, 1-cm surgical margins, and less than 1,000 g of liver tissue removed had a greater than 50% estimated 5-year disease-free survival rate. If the metastases were diploid on flow cytometry, an additional survival advantage may have been gained. Inadequate surgical margins led to high rates of liver-only recurrence. Nonhepatic recurrence was unrelated to surgical margins. Intraoperative liver examination by ultrasound during primary colon cancer resection and adjuvant chemotherapy may offer earlier selection of biologically appropriate patients and improved outcome; both recommendations require clinical trials. 相似文献
7.
Perforated colorectal neoplasms: correlation of clinical, contrast enema, and CT examinations 总被引:2,自引:0,他引:2
Hulnick DH; Megibow AJ; Balthazar EJ; Gordon RB; Surapenini R; Bosniak MA 《Radiology》1987,164(3):611-615
Results of clinical, contrast enema (CE), and computed tomographic (CT) examinations in 39 patients with perforated colorectal neoplasms were retrospectively reviewed. Twenty patients were toxemic at initial presentation, but in only four patients was the diagnosis of perforated colorectal neoplasm initially suspected clinically. CE study was performed in 22 patients and enabled the diagnosis of perforated neoplasm in 11 cases, neoplasm alone in eight, and neither neoplasm nor perforation in three. CT was performed in 38 patients and enabled the diagnosis of perforated neoplasm in 36; pericolic phlegmon but no mass lesion was evident in two. In 16 patients, CT also demonstrated metastatic disease. Because of its reliability in establishing the diagnosis and staging the extent of the inflammatory and neoplastic disease, CT is indicated in cases of suspected or proved perforated colorectal neoplasm and in cases in which CE study findings are indeterminate or suggestive of perforated neoplasm. 相似文献
8.
D. D. Thomas A. M. Fogelman J. N. Miller M. A. Lovett 《European journal of epidemiology》1989,5(1):15-21
Syphilis is a chronic disease characterized by hematogenous dissemination of Treponema pallidum into tissues such as the cardiovascular and central nervous systems. In order to test whether these aspects of the pathogenesis of syphilis reflect an ability of T. pallidum to invade vascular entothelial surfaces, we explored the association of T. pallidum with human and rabbit endothelial cells in vitro. Using radiolabeled motile organisms, we found that treponemal attachment was two times greater to rabbit aortic endothelial cells and human umbilical endothelial cells than to HeLa cells. Mild trypsinization of attached treponemes resulted in release from cells of all organisms detectable by darkfield microscopy without visible damage to the monolayer. Nevertheless, 25% of the counts representing T. pallidum remained associated with the cell monolayers. Further trypsin treatment to release the monolayer and differential centrifugation showed that 80% of the remaining cell-associated counts were not within the cells. These results suggest that some treponemes had associated with the monolayer in a trypsin resistant niche. Additionally, motile T. pallidum passed through tight functioned endothelial cell monolayers on membrane filters under conditions were heat-killed T. pallidum and the host indigenous nonpathogen. T. phagedenis biotype Reiter failed to do so. Electron micrographs of transverse sections through the monolayers showed many T. pallidum in junctions between endothelial cells. These studies suggest that T. pallidum may leave the circulation by passing between endothelial cells. 相似文献
9.
10.
Insulin and insulin-like growth factor I binding to cultured rat glomerular mesangial cells 总被引:2,自引:0,他引:2
The potential effects of insulin and insulin-like growth factor I (IGF-I) on mesangial cell (MC) metabolism and growth were examined. Radiolabeled insulin or IGF-I were incubated with cell membranes from rapidly proliferating (subconfluent) or nonproliferating (confluent) MC in the presence of increasing concentrations of unlabeled heterologous and homologous ligands (0-10(-6) M). Insulin binding to MC was specific and saturable, with Scatchard analysis of binding data showing the characteristic curvilinear plot. The predicted insulin binding maximum of 4.2 X 10(-12) M/100 micrograms protein for a theoretical high affinity site was consistent with a relatively low density of receptors, which were the same in proliferating and nonproliferating cell preparations. Specific binding of IGF-I to MC was also demonstrated. Binding data for membranes from proliferating cultures generated a linear Scatchard plot, which predicted a binding maximum of 3.5-9.7 X 10(-11) M/100 micrograms protein and a Kd of 2.0-3.2 X 10(-9) M. In contrast, membranes from nonproliferating cultures had no demonstrable specific binding of IGF-I. Covalent cross-linking of radiolabeled IGF-I to membranes from subconfluent cells demonstrated specific binding to a 145K membrane protein. A 95K membrane protein from a partially purified receptor preparation demonstrated autophosphorylation when incubated with 5 X 10(-9) M IGF-I. Incubation of MC with 10(-9) M IGF-I doubled cellular growth rates, an effect that could be duplicated only with high concentrations (10(-6) M) of insulin. These observations indicate that MC express predominantly receptors for IGF-I, and that growth stimulatory effects of physiological concentrations of IGF-I and pharmacological concentrations of insulin are probably mediated through the IGF-I receptor. 相似文献