全文获取类型
收费全文 | 986篇 |
免费 | 74篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 62篇 |
妇产科学 | 12篇 |
基础医学 | 98篇 |
口腔科学 | 31篇 |
临床医学 | 165篇 |
内科学 | 210篇 |
皮肤病学 | 13篇 |
神经病学 | 35篇 |
特种医学 | 245篇 |
外科学 | 62篇 |
综合类 | 21篇 |
预防医学 | 34篇 |
眼科学 | 10篇 |
药学 | 33篇 |
中国医学 | 5篇 |
肿瘤学 | 28篇 |
出版年
2024年 | 3篇 |
2023年 | 8篇 |
2022年 | 2篇 |
2021年 | 12篇 |
2020年 | 8篇 |
2019年 | 7篇 |
2018年 | 26篇 |
2017年 | 11篇 |
2016年 | 18篇 |
2015年 | 24篇 |
2014年 | 28篇 |
2013年 | 28篇 |
2012年 | 19篇 |
2011年 | 22篇 |
2010年 | 39篇 |
2009年 | 58篇 |
2008年 | 31篇 |
2007年 | 10篇 |
2006年 | 17篇 |
2005年 | 6篇 |
2004年 | 11篇 |
2003年 | 15篇 |
2002年 | 14篇 |
2001年 | 15篇 |
2000年 | 12篇 |
1999年 | 14篇 |
1998年 | 49篇 |
1997年 | 52篇 |
1996年 | 64篇 |
1995年 | 49篇 |
1994年 | 43篇 |
1993年 | 47篇 |
1992年 | 15篇 |
1991年 | 7篇 |
1990年 | 16篇 |
1989年 | 34篇 |
1988年 | 30篇 |
1987年 | 32篇 |
1986年 | 34篇 |
1985年 | 23篇 |
1984年 | 15篇 |
1983年 | 9篇 |
1982年 | 22篇 |
1981年 | 14篇 |
1980年 | 9篇 |
1979年 | 2篇 |
1978年 | 5篇 |
1977年 | 12篇 |
1976年 | 12篇 |
1975年 | 13篇 |
排序方式: 共有1067条查询结果,搜索用时 15 毫秒
71.
Casanueva FF Molitch ME Schlechte JA Abs R Bonert V Bronstein MD Brue T Cappabianca P Colao A Fahlbusch R Fideleff H Hadani M Kelly P Kleinberg D Laws ED Marek J Scanlon M Sobrinho LG Wass JAH Giustina A 吴哲褒 张亚卓 《中华神经外科杂志》2008,24(8)
3.男性:高催乳素血症通常导致阳痿、不孕和性功能低下.男性患者通常为大腺瘤,有神经系统症状.其原因可能是对症状认识的延误或者肿瘤生物学行为的差异. 相似文献
72.
Speech-controlled generation of radiology reports 总被引:1,自引:0,他引:1
Robbins AH; Horowitz DM; Srinivasan MK; Vincent ME; Shaffer K; Sadowsky NL; Sonnenfeld M 《Radiology》1987,164(2):569-573
Voice entry has been successfully employed to generate radiology reports with a word recognizer with a 1,000-word lexicon capacity. About 50% of reports were able to be dictated with a single 900-word lexicon. This was split into five sections by anatomic or subspecialty application. Each was augmented to 900 words. By switching from one lexicon to another, it was possible to dictate more than 70% of reports. With exclusive use of three lexicons in subspecialty areas (gastrointestinal radiology, neuroradiology, and mammography), and with further modification of the respective vocabulary, it has been possible to employ the system 88% of the time. Twelve percent of cases included wording that was beyond the scope of the lexicon. Computer subsets that allow different translations of some words when used in different contexts have been used. Some of these are used as triggers that will print whole lines, sentences, or even complete reports. Dictation times with voice entry take about 20% longer. Recognition reliability has been greater than 95%. 相似文献
73.
Platelets secrete a low-molecular-weight protein, platelet factor four (PF-4), which binds to and neutralizes heparin and related sulfated glycosaminoglycans (GAGs). To examine the interactions of PF-4 with the GAGs present on endothelial cell surfaces, we incubated 125I-PF-4 with cell suspensions derived from confluent monolayers of cultured bovine aortic endothelium. Binding of 125I-PF-4 was inhibited by a 100-fold excess of nonradioactive PF-4 and varied with duration and temperature of incubation. At 4 degrees C, binding reached equilibrium at 20 minutes with kd = 2.87 mumol/L and Bmax of 63.83 pmol/10(5) cells. Binding capacity was reduced 83.4% by brief incubation of endothelial cells with trypsin and 46.67% by incubation with Flavobacterium heparinase, but was unchanged by chondroitin-ABCase treatment. At 37 degrees C, PF-4 was internalized by confluent monolayer of bovine aortic endothelial cells primarily through low-affinity adsorptive endocytosis. The internalized PF-4 was degraded to amino acids and small peptides with 50% conversion after 18-hour incubation. These studies demonstrate that a secreted platelet protein can bind to and enter endothelial cells. Binding may explain the rapid clearance of released PF-4 from plasma and could have important local effects on endothelial structure and function. 相似文献
74.
We characterized neutrophil autoantigens using an immunoblotting technique with antibodies obtained from patients with autoimmune neutropenia. These results were correlated with serologic characterization of the antibodies, using indirect immunofluorescence and leukoagglutination. Of the 17 sera immunoblotted, 16 showed discrete bands in the molecular weight range of 30 to 112. Three patients with Felty's syndrome reacted with an antigenic target of 80 to 84 Kd molecular mass, a finding not seen in any of the other patients studied. By serologic testing, none of the autoimmune sera showed serologic specificity for any known neutrophil-specific alloantigen. Using an anti-NA-1 serum, we identified antigenic targets at 40, 50, and 101 Kd in both NA-1-positive and NA-1-negative neutrophils. Ten of 17 autoimmune sera showed reactivity in this corresponding range. These studies demonstrate that immunoblotting may be used to identify antigenic targets in autoimmune neutropenia and may suggest a specificity of these antibodies not definable by serologic techniques. Correlation of immunoblot reactivity with disease states associated with immune neutropenia may be useful in the study of the pathogenesis of the different forms of autoimmune neutropenia. 相似文献
75.
Delayed hepatic CT scanning: increased confidence and improved detection of hepatic metastases 总被引:1,自引:0,他引:1
Bernardino ME; Erwin BC; Steinberg HV; Baumgartner BR; Torres WE; Gedgaudas- McClees RK 《Radiology》1986,159(1):71-74
Fifty oncologic patients with suspected hepatic metastases were prospectively evaluated by dynamic sequential hepatic computed tomography (DSHCT) and by delayed iodine hepatic computed tomography (DICT) scanning. DICT scanning was performed 4-6 hours following administration of 60 g of intravenous iodine. Both techniques were evaluated for lesion definition relative to the adjacent hepatic parenchyma and for numbers of metastases detected. Metastases were detected by both techniques in 26 patients. Fifteen patients (58%) had lesions better defined by DICT. DICT scanning detected more metastases in seven of these 15 patients. In eight patients (31%), there was no difference between the two techniques in numbers of masses detected or lesion definition. In three cases (11%), metastases were more confidently identified on the initial or DSHCT scan. DICT scanning, as described, is useful in defining and detecting hepatic metastases, especially where there is questionable hepatic involvement or better quantification of size is necessary. 相似文献
76.
V. de las Alas MD W. D. Voorhees PhD L. A. Geddes ME PhD J. D. Bourland PhD W. E. Schoenlein 《Journal of clinical monitoring and computing》1990,6(3):183-185
In 4 spontaneously breathing, barbiturate-anesthetized dogs, hyperthermia was induced with 2,4-dinitrophenol while rectal
temperature, heart rate, mean blood pressure, end-tidal carbon dioxide, and carbon dioxide production (milliliters per minute)
were measured continuously. The latter was determined with a pneumotachygraph (to obtain respired volume) and an infrared
carbon dioxide analyzer that measured inspired and expired carbon dioxide concentration. Of the five physiologic measurements,
the increase in carbon dioxide production preceded the increase in rectal temperature by more than 120 seconds. End-tidal
carbon dioxide was an unreliable indicator in the spontaneously breathing animal of approaching hyperthermia during spontaneous
breathing due to a transient tachypnea, which decreased end-tidal carbon dioxide. The carbon dioxide production (milliliters
per minute) increased immediately and reached three to five times the control value. Blood pressure and heart rate were insensitive
indicators of approaching hyperthermia. 相似文献
77.
Carotid artery: percutaneous transbrachial selective arteriography with a 4-F catheter 总被引:1,自引:0,他引:1
Bilateral selective common carotid artery catheterization was attempted in 72 patients by means of percutaneous placement of a 4-F catheter from a right brachial artery puncture site in the antecubital fossa. The success rate was high (95.8%) and the complication rate low (6.9%), and there were no instances of brachial artery spasm or thrombosis. The experience, while small, suggests that selective common carotid arteriography can be done safely and efficaciously from the right brachial artery approach. 相似文献
78.
79.
Anxiety in patients undergoing MR imaging 总被引:6,自引:0,他引:6
To determine and quantify the major sources of anxiety for patients undergoing magnetic resonance (MR) imaging and to suggest means by which to eliminate or diminish their negative effects, the authors studied anxiety in 46 subjects. Of these, 20 randomly selected subjects who successfully completed the examination participated in exit interviews. Six subjects who terminated the examination before completion also completed exit interviews. Pre-imaging and postimaging questionnaires (state-trait anxiety inventory) were administered to measure anxiety in the 20 other subjects. Anxiety was associated with the constrictive dimensions of the magnet bore, examination duration, coil noise, and temperature within the bore. Preparation at the point of referral was consistently absent, incomplete, or misleading. Patients used identifiable strategies to cope with the examination: blinding, breathing relaxation techniques, visualization of pleasant images, and performance of mental exercises. 相似文献
80.
Di Chiro G; Girton ME; Frank JA; Dietz MJ; Gansow OA; Wright DC; Dwyer AJ 《Radiology》1986,160(1):221-222
Canine cerebrospinal fluid rhinorrhea, which occurs frequently in purebred beagles, was demonstrated in two dogs on magnetic resonance images after cisternal introduction of gadolinium-DTPA dimeglumine. 相似文献