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991.
Bossi P Tegnell A Baka A Van Loock F Hendriks J Werner A Maidhof H Gouvras G;Task Force on Biological Chemical Agent Threats Public Health Directorate European Commission Luxembourg 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》2004,9(12):E15-E16
Interest in Brucella species as a biological weapon stems from the fact that airborne transmission of the agent is possible. It is highly contagious and enters through mucous membranes such as the conjunctiva, oropharynx, respiratory tract and skin abrasions. It has been estimated that 10-100 organisms only are sufficient to constitute an infectious aerosol dose for humans. Signs and symptoms are similar in patients whatever the route of transmission and are mostly non-specific. Symptoms of patients infected by aerosol are indistinguishable from those of patients infected by other routes. Regimens containing doxycycline plus streptomycin or doxycycline plus rifampin are effective for most forms of brucellosis. Isolation of patients is not necessary. Trimethoprim-sulfamethoxazole and fluoroquinolones also have good results against Brucella, but are associated with high relapse rates when used as monotherapy. The combination of ofloxacin plus rifampicin is associated with good results. Even if there is little evidence to support its utility for post-exposure prophylaxis, doxycycline plus rifampicin is recommended for 3 to 6 weeks. 相似文献
992.
Clinical Rheumatology - cDNA cloning has been a highly successful tool in elucidating the structure of U- and Y-RNA associated proteins. Whereas sera from autoimmune patients have often been... 相似文献
993.
Guido Germano Paul B Kavanagh Piotr J Slomka Serge D Van Kriekinge Geoff Pollard Daniel S Berman 《Journal of nuclear cardiology》2007,14(4):433-454
Cedars-Sinai's approach to the automation of gated perfusion single photon emission computed tomography (SPECT) imaging is based on the identification of key procedural steps (processing, quantitation, reporting), each of which is then implemented, in completely automated fashion, by use of mathematic algorithms and logical rules combined into expert systems. Our current suite of software applications has been designed to be platform- and operating system-independent, and every algorithm is based on the same 3-dimensional sampling scheme for the myocardium. The widespread acceptance of quantitative software by the nuclear cardiology community (QGS alone is used at over 20,000 locations) has provided the opportunity for extensive validation of quantitative measurements of myocardial perfusion and function, in our opinion, helping to make nuclear cardiology the most accurate and reproducible modality available for the assessment of the human heart. 相似文献
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The present study is concerned with the metabolic fate of palmitate, oleate and linoleate in isolated rat lung type II cells. The cells readily oxidize the exogenously supplied fatty acids to CO2 and incorporate them into lipids. The distribution between the pathways of oxidation and esterification is similar for saturated and unsaturated fatty acids. The majority of the fatty acids taken up by the cells is utilized for lipid synthesis. The fatty acids are incorporated preferentially into phospholipids, particularly into phosphatidylcholine. Addition of unsaturated fatty acids decreases the utilization of palmitate by type II cells. The distribution of palmitate between oxidation and esterification is not altered in the presence of unsaturated fatty acids. Addition of carnitine stimulates the fatty acid oxidation and decreases the esterification of fatty acids. 相似文献
997.
Jin L Chico-Galdo V Massart C Gervy C De Maertelaere V Friedman M Van Sande J 《The Journal of endocrinology》2008,198(2):301-307
Chronic administration of acrylamide has been shown to induce thyroid tumors in rat. In vitro acrylamide also causes DNA damage, as demonstrated by the comet assay, in various types of cells including human thyroid cells and lymphocytes, as well as rat thyroid cell lines. In this work, mice were administered acrylamide in their drinking water in doses comparable with those used in rats, i.e., around 3-4 mg/kg per day for mice treated 2, 6, and 8 months. Some of the mice were also treated with thyroxine (T(4)) to depress the activity of the thyroid. Others were treated with methimazole that inhibits thyroid hormone synthesis and consequently secretion and thus induces TSH secretion and thyroid activation. These moderate treatments were shown to have their known effect on the thyroid (e.g. thyroid hormone and thyrotropin serum levels, thyroid gland morphology...). Besides, T(4) induced an important polydipsia and degenerative hypertrophy of adrenal medulla. Acrylamide exerted various discrete effects and at high doses caused peripheral neuropathy, as demonstrated by hind-leg paralysis. However, it did not induce thyroid tumorigenesis. These results show that the thyroid tumorigenic effects of acrylamide are not observed in another rodent species, the mouse, and suggest the necessity of an epidemiological study in human to conclude on a public health policy. 相似文献
998.
Goldberg JM Bosgraaf L Van Haastert PJ Smith JL 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(10):6749-6754
In Dictyostelium, a transient increase in intracellular cGMP is important for cytoskeletal rearrangements during chemotaxis. There must be cGMP-binding proteins in Dictyostelium that regulate key cytoskeletal components after treatment with chemoattractants, but to date, no such proteins have been identified. Using a bioinformatics approach, we have found four candidate cGMP-binding proteins (GbpA-D). GbpA and -B have two tandem cGMP-binding sites downstream of a metallo beta-lactamase domain, a superfamily that includes cAMP phosphodiesterases. GbpC contains the following nine domains (in order): leucine-rich repeats, Ras, MEK kinase, Ras guanine nucleotide exchange factor N-terminal (RasGEF-N), DEP, RasGEF, cGMP-binding, GRAM, and a second cGMP-binding domain. GbpD is related to GbpC, but is much shorter; it begins with the RasGEF-N domain, and lacks the DEP domain. Disruption of the gbpC gene results in loss of all high-affinity cGMP-binding activity present in the soluble cellular fraction. GbpC mRNA levels increase dramatically 8 h after starvation is initiated. GbpA, -B, and -D mRNA levels show less dramatic changes, with gbpA mRNA levels highest 4 h into starvation, gbpB mRNA levels highest in vegetative cells, and gbpD levels highest at 8 h. The identification of these genes is the first step in a molecular approach to studying downstream effects of cGMP signaling in Dictyostelium. 相似文献
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