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81.
Bruce Lubotsky Levin Dr.P.H. Robert M. Friedman Ph.D. Jack Zusman M.D. M.P.H. 《The Psychiatric quarterly》1988,59(2):83-87
The papers which follow are revised and expanded versions of presentations made at the Conference on Improving Florida's Services for the Mentally Ill: The Role of Psychiatry, held in Tallahassee, Florida on October 7–8, 1986, and organized by the Florida Mental Health Institute, University of South Florida. The conference was sponsored by the Florida Department of Health and Rehabilitative Services through the Committee on Public Psychiatry. The authors and their organizational affiliations are listed below 相似文献
82.
Carbon-14 data on atmospheric CO2 as well as on plant material (tree leaves and wheat) from the vicinity of two German boiling water reactors (Philippsburg and Isar/Ohu) are reported. Atmospheric CO2 samples taken routinely with an integration time of one or two weeks 1.75 km downwind of the Philippsburg reactor (900 MW electrical power) show a maximum 14C excess concentration of delta 14C (excess) = 300 +/- 7%, corresponding to 12.7 mBq m-3 (STP air). The long-term average excess amounts to delta 14C (excess) = 47 +/- 3%, corresponding to 2.0 mBq m-3 (STP air). The concentrations observed with plant material at the same sampling site range between delta 14C (excess) = 0% and 120%, corresponding to 0 and 27 mBq (g carbon)-1. With the meteorological dispersion parameters actually measured at the nuclear power plants, the dispersion factors for the various sampling sites and for the individual periods of sampling were calculated on the basis of a one-dimensional Gaussian plume model. With the observed 14C excess concentrations and the dispersion factor, a "theoretical" (i.e. calculated) reactor 14C source strength is then determined. For the Philippsburg reactor, which is situated in the flat Rhine valley, the "theoretical" and the observed yearly mean 14C emissions compare rather well (within a factor of 2). A significant systematical deviation from the model was found in the concentration decrease with source distance: the decrease predicted between the 1.75-km and 3.25-km distances is steeper than actually observed. The 14C excess concentrations found in tree leaves around the Isar/Ohu reactor (907 MW electrical power) at 1-2 km distance fall into the same range as observed at Philippsburg. In the hilly terrain at this reactor site, the model calculations agree well with the observed values up to a distance of 1 km if the relative elevation of the sampling site is taken into account by introducing a "reduced stack height" in the model calculations. This method fails in predicting the concentrations at distances greater than 1 km from the source. 相似文献
83.
Proteus syndrome 总被引:2,自引:0,他引:2
C P Samlaska S W Levin W D James P M Benson J C Walker P C Perlik 《Archives of dermatology》1989,125(8):1109-1114
The term Proteus syndrome was coined in 1983 to describe a disorder of skeletal, hamartomatous, and other mesodermal malformations. The syndrome was named after the Greek god Proteus, whose name means "the Polymorphous." Clinical features of this new syndrome are currently being defined. Including the case reported herein, we have found 34 patients with Proteus syndrome described in the English literature. Major clinical findings, defined as those findings seen in more than half of the cases, include hemihypertrophy, macrodactyly, exostoses, epidermal nevi, characteristic cerebriform masses involving the plantar or palmar surfaces, a variety of subcutaneous masses, and scoliosis. Histologic examination of subcutaneous masses has identified a variety of lipomatous, hamartomatous, and angiomatous tumors. 相似文献
84.
Randomized studies involving long-term follow-up are vulnerable to the effects of unplanned crossover. In surgical studies, such crossover usually occurs when control patients become more symptomatic and undergo operation. In several large studies of coronary bypass grafting, crossover ranged from 25% to 38%. The most common way of dealing with this problem is to apply the "intention-to-treat" principle, which analyzes such crossovers with their originally assigned groups. Besides the logical problem of counting a control patient who actually undergoes operation as "nonsurgical," a more subtle problem arises in terms of statistical power. When statistical power is low, a truly effective treatment may be mistakenly labeled as no better than control, causing a potentially valuable form of therapy to be ignored or discarded. This analysis demonstrates that crossover may have a profound effect on the statistical power of randomized studies and presents a method for predicting the effect of such crossover on statistical power. 相似文献
85.
Autosensitivity of Pseudomonas aeruginosa to Its Own Pyocin 总被引:3,自引:0,他引:3
Sensitivity of smooth and mucoid Pseudomonas aeruginosa strains from the same patient to their own pyocins was found to be greater at 20 than at 35 C. 相似文献
86.
Several lines of evidence suggest that the brain exhibits reduced plasticity with aging. However, a variety of soluble neurite outgrowth-promoting factors, such as neurotrophins, are not decreased in the aged brain, and aged neurons do not possess dramatically reduced growth potential. The possibility that aging results in reduced baseline substrate-bound neurite outgrowth-promoting activity in the central nervous system (CNS) was evaluated using tissue section culture. There were clear differences between brain regions in the extent of neurite outgrowth on both young and aged brain sections. However, no differences in the extent of neurite outgrowth were observed as a function of age. These results suggest that aging of the rat CNS is not accompanied by major alterations in the baseline neurite outgrowth-promoting substrate properties of the tissue. 相似文献
87.
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90.
Immunity reduces reservoir host competence of Peromyscus leucopus for Ehrlichia phagocytophila 下载免费PDF全文
Infection with Ehrlichia phagocytophila in white-footed mice is transient and followed by a strong immune response. We investigated whether the presence of acquired immunity against E. phagocytophila precludes white-footed mice from further maintenance of this agent in nature. Mice were infected with E. phagocytophila via tick bite and challenged either 12 or 16 weeks later by Ixodes scapularis nymphs infected with the same agent. Xenodiagnostic larvae fed upon each mouse simultaneously with challenging nymphs and 1 week thereafter. Ticks were tested for the agent by PCR, and the prevalence of infection was compared to that in ticks that fed upon nonimmune control mice. Only 30% of immunized mice sustained cofeeding transmission of E. phagocytophila between simultaneously feeding infected and uninfected ticks, compared to 100% of control mice. An average of 6.3% of xenodiagnostic ticks acquired Ehrlichia from previously immunized mice when fed 1 week after the challenge, compared to 82.5% infection in the control group. Although an immune response to a single infection with E. phagocytophila in white-footed mice provided only partial protection against reinfection with the same agent, the majority of mice were rendered reservoir incompetent for at least 12 to 16 weeks. Immunity acquired by mice during I. scapularis nymphal activity in early summer may exclude a large proportion of the mouse population from maintaining E. phagocytophila during the period of larval activity later in the season. 相似文献