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711.
712.
Hepatocellular carcinoma: US evolution in the early stage 总被引:2,自引:0,他引:2
To study the sonographic evolution of hepatocellular carcinoma (HCC) in its early stage, 26 HCCs in 24 patients were observed regularly with real-time ultrasound for a period of 90 to 691 days. In the beginning, 21 tumors were hypoechoic, two isoechoic, and three diffusely hyperechoic. On follow-up, two of the 21 initially hypoechoic HCCs remained the same echodensity, 12 increased in internal echoes but were still hypoechoic, one became isoechoic, four changed to hyperechoic, and the remaining two shifted from hypoechoic to isoechoic and then to hyperechoic. The two initially isoechoic HCCs also gained echogenicity and became hyperechoic. By contrast, the three initially hyperechoic HCCs kept the same echo patterns. The "acquired" hyperechoic HCCs were inhomogeneous in echodensity and larger in size whereas the three originally hyperechoic HCCs were homogeneous and smaller. It is concluded that most small HCCs evolve progressively from hypoechoic to isoechoic and then to inhomogeneously hyperechoic patterns as they grow; a few HCCs have diffusely high echogenicity from the beginning and retain the same features thereafter. 相似文献
713.
During a 3-year period, 12,158 cardiac catheterizations were performed via the brachial artery. During this same period, 106 patients were operated on for complications of brachial artery injury and/or thrombosis, an incidence of 0.9%. The indication for the cardiac catheterization was coronary artery disease in almost 92% of the patients. Early (less than 4 days) brachial artery repair was done in 90% of the patients. The operative findings were thrombosis (91%), intimal injury (54%), stenosis (13%), laceration and/or perforation (11%), and atherosclerotic plaque (6%). Because of vessel injury, localized resection was done in two thirds of the patients. Vascular continuity was obtained with axial reanastomosis in 45 patients and interposition vein graft in 26 patients. Primary lateral repair was performed in 23 patients (22%). Ninety-five percent (101 patients) had initial excellent results. Of the five patients who required reoperation, flow was restored in four patients. Thus, 99% of patients had restoration of a patent brachial artery. Contributing factors for brachial artery complications are "redo" catheterization, prolonged catheterization time, catheter change, brachial artery atherosclerosis, improper arteriotomy closure, experience of cardiologist, female patient, and failure to use heparin. Because of the unpredictability of ischemic symptoms occurring after brachial artery thrombosis, the need for bypass graft surgery when delayed, and the good results with early surgical intervention, early exploration of brachial artery complications after cardiac catheterization and appropriate repair are recommended. 相似文献
714.
McCollum G 《Trends in neurosciences》2000,23(8):334-336
Social rather than scientific barriers are impeding neuroscience theory. There are plenty of experimental data and mathematical methods to develop a rigorous, mathematical theory in neuroscience. However, structural mathematical efforts are being suffocated by the requirement to produce numbers immediately. Also theoretical development is tied too closely to one experimental group. The social barriers can be addressed by: (1) judging theory by structural accuracy rather than numerical output; (2) recognizing mathematical theory (not just computational modeling) as a method for producing insight into neurobiological phenomena; (3) funding fundamental theoretical neuroscience and (4) recognizing theoretical neuroscientists as neuroscientists. 相似文献
715.
Cade T DeBerg C Hagstrom P McCollum L Stewart R 《Journal of AHIMA / American Health Information Management Association》1992,63(12):58-61
There is tremendous potential in auto ID technologies for increasing productivity and accuracy in the management of health information. We must make a commitment to integrate keyless data capture technologies into medical record administration and medical record technology curricula. Our profession will seize the opportunity if we can educate students and practitioners in the knowledge and skills to unleash this potential. A recent study of medical record administration, and medical record technology, programs by Elaine Patrikas revealed that, at best, some programs devote a maximum of 10 hours of instructional time to the teaching of keyless data capture technologies. HIM professionals can aggressively pursue applications that demonstrate tremendous cost savings, so that upper management will seriously consider them. Improvements in the flow of, and access to, information do directly impact patient care thus helping our profession fulfill its mission and preparing tomorrow's leaders and decision makers. 相似文献
716.
Kirkpatrick UJ Burrows G Blann A McCollum CN 《Experimental and molecular pathology》1999,65(3):111-120
Neutrophil activation and adhesion to the endothelium are thought to be central in the inflammatory response to reperfusion after ischemia. This study explores whether the severity of tissue hypoxia can be related to a biochemical measure. Venous blood was sampled from 20 volunteers undergoing tourniquet-induced forearm ischemia for 10 min and subsequent reperfusion. Samples were analyzed for neutrophil count, neutrophil hydrogen peroxide generation measured by flow cytometry, plasma thromboxane (a marker of platelet activation), the endogenous antioxidant glutathione peroxidase, and thrombomodulin, a marker of endothelial cell damage. Forearm oxygen saturation by near-infrared spectroscopy was monitored throughout the experiment. Neutrophil hydrogen peroxide generation fell from an initial mean fluorescent intensity (MFI) of 0.91 +/- 0.07 to 0.77 +/- 0.09 (mean +/- SE) during ischemia (P < 0.05) and this reduction correlated with severity of hypoxia (r = 0.56, P < 0.01). Plasma levels of glutathione peroxidase were also reduced during ischemia (P < 0.05) whereas plasma thromboxane levels rose (P < 0.05). There were no significant changes in plasma levels of thrombomodulin or circulating neutrophil count. In conclusion, alterations in a measurement of neutrophil function reflect the changes in tissue oxygenation and may act as a biochemical predictor of the severity of an ischemic injury. 相似文献
717.
H P Shotwell J C Caporossi R W McCollum J F Mellor 《American Industrial Hygiene Association journal》1979,40(8):737-742
Validation of solid sorbent air sampling-analytical systems used to evaluate employee exposures to substances in the work place air is a fundamental part of any industrial hygiene air sampling program. In April, 1977, the National Institute for Occupational Safety and Health (NIOSH) published "Documentation of the NIOSH Validation tests", as part of the Standards Completion Project. This paper presents an alternative validation procedure which is more easily understood, is more rigorous, and provides for greater accuracy and precision. 相似文献
718.
J T Harries D P Muller J P McCollum A Lipson E Roma A P Norman 《Archives of disease in childhood》1979,54(1):19-24
The quantitative and qualitative distribution of bile salts in the duodenal juice of 13 patients with cystic fibrosis (CF) was studied after a test meal. The effects of triolein (TO), bovine serum albumin (BSA), and ricinoleic acid (RA) on the absorption of taurocholate (TCA) in the distal ileum of the rat in vivo was also studied. The mean (and ranges) of total bile salt concentrations, glycine: taurine conjugate ratios, and percentage of dihydroxy bile salts in the patients with CF and pancreatic insufficiency were 3.5 (1.3--6.6) mmol/l, 8.6 (greater than 10-3.1), and 37 (10--60) compared with control values of 7.4 (3.0--16.0) mmol/l, 3.0 (1.3--4.5), and 61 (52--70) respectively. The differences between the control and CF values were statistically significant (P less than 0.01--P less than 0.001). Three of the 13 CF patients had total bile salt concentrations less than 2 mmol/l, 8 had much higher glycine: taurine ratios, and 8 had a reduced percentage of dihydroxy bile salts. In 2 patients with normal pancreatic enzyme activities, duodenal bile salts were both quantitatively and qualitatively normal. TO (10 and 30 mmol/l), BSA (3%), and RA (5 mmol/l) had no inhibitory effect on the ileal absorption of TCA. These results show pronounced abnormalities of duodenal juice bile salts in CF with pancreatic insufficiency consistent with a broken enterohepatic circulation (EHC); such abnormalities may contribute to defective lipid absorption in CF. The data in the experimental animal do not support the suggestion that unhydrolysed dietary substrates play a role in the pathophysiology of the broken EHC. 相似文献
719.
D Ogilvie J P McCollum S Packer J Manning J Oyesiku D P Muller J T Harries 《Archives of disease in childhood》1976,51(10):790-795
24-hour urinary outputs of oxalate, calcium, and magnesium have been determined in a total of 62 children aged 3 months to 17 years who fell into the following groups: (i) 16 normal controls, (ii) 3 with primary hyperoxaluria, (iii) 9 with small and/or large intestinal resections, (iv) 9 with untreated coeliac disease, (v) 5 with pancreatic dysfunction, and (vi) a miscellaneous group of 20 children with a variety of intestinal disorders. Taken as a whole, 58% of patients with intestinal disorders had hyperoxaluria, and of these 7% had urinary outputs of oxalate which fell within the range seen in primary hyperoxaluria. The proportion of children with hyperoxaluria in the different diagnostic groups was as follows: intestinal resections (78%), coeliac disease (67%), pancreatic dysfunction (80%), and miscellaneous (45%). 35% of the patients with hyperoxaluria had hypercalciuria, whereas magnesium excretion was normal in all subjects studied. In 2 patients treatment of the underlying condition was accompanied by a return of oxalate excretion to normal. These results indicate that hyperoxaluria and hypercalciuria are common in children with a variety of intestinal disorders, and that such children may be at risk of developing renal calculi without early diagnosis and treatment. 相似文献
720.
目的脑电图(electroencephalogram,EEG)是通过脑电描记仪将脑自身微弱的生物电放大记录成为一种脑电谱图,以帮助诊断疾病的一种现代辅助检查方法。早期对闭眼和睁眼差异的研究结果多集中在位于枕叶-顶叶的α波的幅度的变化,闭眼幅度大于睁眼。本文主要探讨单侧眼睛(左眼和右眼)分别睁开和闭合时所引起的七波段脑电图谱:Delta(0.5~3.5 Hz),Theta(4~7Hz),Alpha-1(7.5~9.5 Hz),Alpha-2(10~12 Hz),Beta-1(13~23 Hz),Beta-2(24~34 Hz)and Gamma(35~45 Hz)的差异。方法受试者为15名健康男性(年龄19~27岁),静息状态下,在安静舒适的室内环境中,将随机单侧睁眼闭眼(左开/左闭,右开/右闭)作为刺激,采用电脑自动记录七波段脑电图(128-导EEG)。结果静息状态下的脑电区域能量:中间频率波段alpha-1与alpha-2闭眼时明显高于睁眼时(alpha-1,P=0.038;alpha-2,P=0.02),而比较单侧睁眼闭眼alpha-1与alpha-2时,差异无统计学意义(alpha-1,P=0.502;alpha-2,P=0.984),其他波段差异无统计学意义。结论闭眼情况下α波功率显著高于睁眼,而在比较七波段单侧眼睛睁闭时,差异无统计学意义,说明单侧外界光线刺激引起的对侧大脑半球及视觉皮质的变化,经过视交叉传入,胼胝体整合两边的头脑反应是一种持续性变化(2 min),从而使两侧EEG区域能量图一致。 相似文献