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71.
I W Iglehart J D Sutton J C Bender R A Shaw C M Ziminski P A Holt M C Hochberg T M Zizic E W Engle M B Stevens 《The Journal of rheumatology》1990,17(2):159-162
This prospective, double blind study was undertaken to test the efficacy of intravenous "minipulse" (100 mg) methylprednisolone (MP) therapy versus standard pulse (1000 mg) MP therapy in rheumatoid arthritis (RA). Thirty-six patients with RA synovitis flares were randomized to receive either 100 or 1000 mg MP IV QD x 3 doses. These 2 universally comparable groups exhibited no statistically significant differences in their striking prompt and sustained clinical improvement. These data suggest that minipulse MP is as efficacious as conventional pulse MP in the treatment of RA flares. 相似文献
72.
For study group participants who returned for measurement in 1988, the health promotion program appeared to have a limited effect on health risk indicators and a positive effect on health-related attitudes. The data suggest that decreases in smoking and alcohol consumption may be attributed to the program. The combined evidence after 5 years of improved health behaviors, better health attitudes, and self-reports of lifestyle improvements suggests that the program has a positive impact on habit and attitude changes. 相似文献
73.
Quirk P Ward LC Thomas BJ Holt TL Shepherd RW Cornish BH 《Clinical nutrition (Edinburgh, Scotland)》1995,14(6):348-353
The use of multiple frequency bioelectrical impedance analysis (MFBIA) was compared with single frequency bioelectrical impedance analysis (SFBIA) and anthropometry to estimate the size of the body cell mass (BCM) in a paediatric cystic fibrosis population. BCM was independently determined from the accepted gold standard reference of total body potassium (TBK). MFBIA was used to measure the impedance of the body at 248 frequencies from 4 kHz to 1 MHz. Data were analysed using Cole-Cole plots of reactance versus resistance. The limits of agreement procedure was used to determine the reliability and precision of the different techniques to predict values for TBK, in an individual subject. The results indicate that MFBIA with a precision of 12% offers little improvement over single frequency BIA but is better and more accurate than anthropometry for the prediction of TBK in an individual patient. 相似文献
74.
Elaissari A Holt L Meunier F Voisset C Pichot C Mandrand B Mabilat C 《Journal of biomaterials science. Polymer edition》1999,10(4):403-420
The adsorption of BSA and RNA onto hydrophilic and thermosensitive poly(N-isopropyl-acrylamide) (NIPAM) latex particles was described as a function of pH, ionic strength and temperature. The hydrogel poly(NIPAM) latex was synthesized by precipitation polymerization in the presence of a cationic amino-containing monomer. The latex obtained was characterized in terms of particle size, and electrophoretic mobility as a function of pertinent variables: pH, temperature and ionic strength. The adsorption of BSA onto the latex was investigated to identify the conditions at which the adsorbed amount of BSA was negligible. The adsorption of RNA was studied to establish the conditions which give rise to maximal adsorption of RNA. In order to favor the desorption of RNA, desorption was investigated by changing the pH, ionic strength, and temperature. The adsorption of BSA was found to be lower at 20 than at 40 degrees C. However, the adsorption of RNA is drastically affected by the pH and the ionic strength of the medium. Maximal adsorbed amounts were obtained at acidic pH, 20 degrees C, and low ionic strength. The adsorption is shown to decrease when the pH, temperature and ionic strength increase, implying that the adsorption was mainly governed by electrostatic interactions. Maximal release of RNA molecules was obtained at high ionic strength and basic pH. 相似文献
75.
Computerized information systems are gaining ground in quality improvement, and will become even more important as health plans implement, evaluate, and maintain clinical guidelines. PacifiCare of California explored physicians' attitudes toward applying computerized technologies to direct clinical guidelines. The results indicate not only physician acceptance factors, but illustrate the issues, such as information for medical decision making, that health plans must consider in developing computerized case management systems to manage the care of the chronically ill. 相似文献
76.
This article presents findings from a survey of programmes available for tobacco and alcohol users working in 455 of Australia's top 600 companies. Companies were twice as likely to have programmes for smokers (43%) as for problem drinkers (24%) and these programmes were more apparent in large companies. The majority of programmes for smoking were delivered within a health promotion context which included other life-style issues, such as nutrition, exercise, weight management and stress management. Although Employee Assistance Programs (EAPs) were the most commonly available type of work-place programme for excessive drinkers and other drug users, followed by Alcoholics Anonymous and local hospital clinics, only 6% had an EAP for alcohol. Only 21% of programmes for smokers and 12% for excessive alcohol users were evaluated. Around one-quarter of companies knew the costs of smoking programmes, and 9% reported costs of conducting programmes for excessive alcohol consumers. 相似文献
77.
In a telephone survey of 455 of the top 600 companies in Australia, around three-quarters reported the existence of restrictions on both smoking and alcohol in the workplace. Forty-six percent of companies had a total ban on smoking at work, 31% had designated limited areas where employees were permitted to smoke, and 23% had no policy on smoking. Seventy-seven percent of companies encouraged a total alcohol-free work environment. The larger the company, the more likely it was to have restrictions on smoking in the work-place, but there was no relationship between the size of the company and alcohol restrictions. Government organizations were more likely to have restrictions on smoking than nongovernment organizations, but this difference was not apparent for alcohol restrictions. The major reasons given for smoking restrictions were related to health and comfort, while those for alcohol were related to work productivity and safety. 相似文献
78.
79.
The contrast required to see Mach bands in a trapezoidal grating has been measured under different conditions. At photopic levels, increasing contrast is required as grating frequency increases. Mach bands are absent at all frequencies in scotopic viewing. Their absence at lower frequencies is not due simply to lack of suprathreshold contrast since at low frequencies contrast sensitivity is little affected by dark adaptation.Trapezoids of diminishing ramp width require increasing contrast until for a square edge a contrast of just greater than 1 would be required. This is difficult to achieve in most subjects.The Chevreul illusion behaves quite differently being unaffected by dark adaptation and grating frequency. 相似文献
80.
Since exogenous hemin has been shown to exert a variety of stimulatory effects on erythroid cells, including the augmentation of hemoglobin synthesis, we determined its effect on early stages of erythroid development by employing clonal cells assays. The addition of hemin at a concentration of 2 X 10(-4) M to cultures of normal murine marrow substantially increased the observed number of primitive BFU-E, which was in contrast to its lack of an effect on more mature erythroid colony-forming cells. This cell-specific enhancement of primitive BFU-E resulted in marrow frequencies equivalent to or exceeding those reported in the presence of "burst-promoting activity." In the presence of hemin, the number of BFU-E was also observed to be linearly related to the number of cells plated at very low plating densities, and the cell titration curve was observed to extrapolate to the origin. The evidence suggests that hemin may be a primary growth regulator of early developmental stages of erythroid progenitor cells. 相似文献