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91.
92.
MAL64
c is a global regulator of α-glucoside fermentation: identification of a new gene involved in melezitose fermentation 总被引:2,自引:0,他引:2
Summary Maltase constitutive mutants at the MAL6 locus have been mapped to the newly identified regulatory gene MAL64
c. We show here that MAL64
c has in addition pleiotropic effects on sugar fermentation: MAL64
c strains constitutively synthesize an -methylglucosidase and can complement a new gene, MTP1, for the fermentation of melezitose and -methylglucoside. MTP1, maps near MAL1, and either encodes a permease which transports melezitose, -methylglucoside, and maltose or regulates the activity of such a permease. This work shows that MAL64
c, a trans-acting regulatory gene, is a global regulatory gene affecting several different pathways of -glucoside metabolism. 相似文献
93.
94.
Perkins A 《Biomedical imaging and intervention journal》2005,1(2):e9-Dec;1(2):e9
Unsealed radionuclides have been in clinical therapeutic use for well over half a century. Following the early inappropriate clinical administrations of radium salts in the early 20th century, the first real clinical benefits became evident with the use of (131)I-sodium iodide for the treatment of hypothyroidism and differentiated thyroid carcinoma and (32)P-sodium phosphate for the treatment of polycythaemia vera. In recent years the use of bone seeking agents (89)Sr, (153)Sm and (186)Re for the palliation of bone pain have become widespread and considerable progress has been evident with the use of (131)I-MIBG and (90)Y-somatostatin receptor binding agents. Although the use of monoclonal antibody based therapeutic products has been slow to evolve, the start of the 21st century has witnessed the first licensed therapeutic antibody conjugates based on (90)Y and (131)I for the treatment of non-Hodgkin's lymphoma. The future clinical utility of this form of therapy will depend upon the development of radiopharmaceutical conjugates capable of selective binding to molecular targets. The availability of some therapeutic radionuclides such as (188)Re produced from the tungsten generator system which can produce activity as required over many months, may make this type of therapy more widely available in some remote and developing countries.Future products will involve cytotoxic radionuclides with appropriate potency, but with physical characteristics that will enable the administration of therapeutic doses with the minimal need for patient isolation. Further developments are likely to involve molecular constructs such as aptamers arising from new developments in biotechnology.Patient trials are still underway and are now examining new methods of administration, dose fractionation and the clinical introduction of alpha emitting radiopharmaceutical conjugates. This review outlines the history, development and future potential of these forms of therapy. 相似文献
95.
Chang CC Eshoa C Kampalath B Shidham VB Perkins S 《American journal of clinical pathology》2000,114(5):807-811
The present study was designed to evaluate the lineage differentiation (particularly monocytic differentiation) of immature myeloid cells in granulocytic sarcoma (GS) by immunohistochemistry and correlate the results with lineage differentiation of blasts in the bone marrow and to determine the degree of maturation of the infiltrating myeloid cells in GS by immunohistochemistry using CD34 and HLA-DR. Immunohistochemical stains were performed on paraffin-embedded tissue from 17 GS lesions with lineage-associated markers: myeloperoxidase, CD68 (KP1), CD68 (PG-Ml), glycophorin A, factor VIII, and CD56; and with markers for blasts and immature myeloid cells: CD34 and HLA-DR. Our results show that positive staining with PG-M1, but not KP1, suggests monocytic differentiation of myeloid cells in GS and correlates with the monocytic differentiation of blasts in the bone marrow. Expression of CD56 is frequent in GS, especially when the marrow blasts have monocytic differentiation, and should not be interpreted as a primary natural-killer cell process. The immature myeloid cells in GS are frequently HLA-DR positive. However, CD34 positivity of the immature myeloid cells is relatively uncommon, except in cases with underlying myelodysplastic syndrome or chronic myelogenous leukemia. 相似文献
96.
M P Chang J L Tanaka S Stosic-Grujicic E K Yamamoto E H Perkins B L Strehler T Makinodan 《International journal of immunopharmacology》1982,4(5):429-436
The differential effect of 2-mercaptoethanol (2-ME) on spleen and bone marrow cells of young and old mice was determined in vitro. Both the ability of spleen cells to proliferate and to generate Ig-secreting cells and the capacity of bone marrow cells to generate myeloid colonies were assessed. All three activities assessed in both young and old mice were enhanced by the presence of 2-ME, but a differential effect with respect to age was noted in only one. This was the polyclonal activating antibody response to bacterial lipopolysaccharide (LPS) in which 2-ME enhanced young spleen cells to a greater extent than old spleen cells, although their mitogenic responses to LPS were enhanced to the same extent. The ability of 2-ME to enhance old spleen B cells to proliferate but not differentiate in their response to LPS would suggest that aging alters certain subpopulations of spleen cells, some of which are sensitive and others insensitive to the potentiation effects of 2-ME. The enhancing action of 2-ME on the proliferative activity of LPS-stimulated young spleen cells was reduced drastically by decreasing the number of T cells by prior treatment of spleen cells with anti-T cell reagent. The proliferative activity was then brought back to normal pretreatment level by adding enriched T cells. Therefore it would appear that regulatory T cells are the target of the enhancing action of 2-ME. The failure of old spleen cells to respond vigorously to the polyclonal activating action of LPS and 2-ME individually and in combination would indicate that age-related alterations may be taking place in the B cells and/or the regulatory cells. Young-old spleen cell mixture study indicates that there are regulatory cells in old spleen cells which can inhibit B cell differentiation but not B cell proliferation. 相似文献
97.
Activity of the enantiomers of 2-amino-5-phosphono-valeric acid as stereospecific antagonists of excitatory aminoacids 总被引:1,自引:0,他引:1
The (+) and (?) enantiomers of 2-amino-5-phosphono-valeric acid have been separated and tested as antagonists of aminoacid excitation of neurones in rat cerebral cortex. The compounds were applied by microiontophoresis. The (?)-isomer was about 8–10 times more active than the racemate in blocking responses to N-methyl-d-aspartate, and was better able to distinguish between N-methyl-d-aspartate and glutamate.The results support the concept of a distinct population of receptors for N-methyl-d-aspartate. 相似文献
98.
Olasveengen Theresa M. Semeraro Federico Ristagno Giuseppe Castren Maaret Handley Anthony Kuzovlev Artem Monsieurs Koenraad G. Raffay Violetta Smyth Michael Soar Jasmeet Svavarsdóttir Hildigunnur Perkins Gavin D. 《Notfall & Rettungsmedizin》2021,24(4):386-405
Notfall + Rettungsmedizin - Der Europäische Rat für Wiederbelebung hat diese Leitlinie – Basismaßnahmen zur Wiederbelebung – auf Grundlage des... 相似文献
99.
100.
Perkins M 《Clinical linguistics & phonetics》1994,8(4):321-336
A common feature of a wide range of language disorders is the tendency to repeat a particular linguistic form-or set of forms-with abnormal frequency. A brief overview is given of the different ways in which disordered language can be repetitive, and the nature of stereotyped and repetitive language is discussed in terms of the reciprocal relationship between frequency of occurrence and productivity. It is argued that measures such as lexical type-token ratio provide only a partial picture of repetitive language, and that linguistic units larger than the word also need to be taken into consideration. An analytical framework incorporating such units is proposed, which is able to characterize and quantify the extent to which a sample of language is repetitive independently of its aetiology. An illustrative analysis is given of a language sample from a brain-damaged adult, and the repetitiveness profiles of four different patients are compared. 相似文献