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991.
This study deals with an important issue that is often encountered with the registration of remote sensing images which are obtained at different times and/or through inter/intra sensors. Remote sensing images may differ significantly in gray-level characteristics and contrast, among other aspects. Thus, it may be difficult to apply directly area-based approaches which are dependent on image intensity values. In this work, a novel image registration approach based on Gaussian-Hermite moments and the Pseudo-RANSAC algorithm is proposed. The problem of intensity difference commonly incurred in multi-temporal or multimodal remote sensing image registration is tackled using features that are invariant to intensity mapping during the feature point matching process. In particular, the feature points are herein represented by a range of newly introduced Gaussian-Hermite moments, and the corresponding feature points in a certain reference image are sought with the Euclidean distance measure. Moreover, an improved RANdom SAmple Consensus (RANSAC) algorithm is presented, reducing computational time complexity while improving performance in stability and accuracy. The final warping of images according to their refined feature points is conducted with bilinear interpolation. The proposed approach has been successfully applied to register synthetic and real remote sensing images, demonstrating its efficacy with systematic experimental evaluations. 相似文献
992.
Laoise Renwick Duncan Stewart Michelle Richardson Mary Lavelle Karen James Claire Hardy Owen Price Len Bowers 《International journal of mental health nursing》2016,25(4):308-318
Aggression and violence are widespread in UK Mental Health Trusts, and are accompanied by negative psychological and physiological consequences for both staff and other patients. Patients who are younger, male, and have a history of substance use and psychosis diagnoses are more likely to display aggression; however, patient factors are not solely responsible for violence, and there are complex circumstances that lead to aggression. Indeed, patient–staff interactions lead to a sizeable portion of aggression and violence on inpatient units, thus they cannot be viewed without considering other forms of conflict and containment that occur before, during, and after the aggressive incident. For this reason, we examined sequences of aggressive incidents in conjunction with other conflict and containment methods used to explore whether there were particular profiles to aggressive incidents. In the present study, 522 adult psychiatric inpatients from 84 acute wards were recruited, and there were 1422 incidents of aggression (verbal, physical against objects, and physical). Cluster analysis revealed that aggressive incident sequences could be classified into four separate groups: solo aggression, aggression–rule breaking, aggression–medication, and aggression–containment. Contrary to our expectations, we did not find physical aggression dominant in the aggression–containment cluster, and while verbal aggression occurred primarily in solo aggression, physical aggression also occurred here. This indicates that the management of aggression is variable, and although some patient factors are linked with different clusters, these do not entirely explain the variation. 相似文献
993.
Age‐predicted maximal heart rate (HRMAX) equations are commonly used for the purpose of prescribing exercise regimens, as criteria for achieving maximal exertion and for diagnostic exercise testing. Despite the growing popularity of upper body exercise in both healthy and clinical settings, no recommendations are available for exercise modes using the smaller upper body muscle mass. The purpose of this study was to determine how well commonly used age‐adjusted prediction equations for HRMAX estimate actual HRMAX for upper body exercise in healthy young and older adults. A total of 30 young (age: 20 ± 2 years, height: 171·9 ± 32·8 cm, mass: 77·7 ± 12·6 kg) and 20 elderly adults (age: 66 ± 6 years, height: 162 ± 8·1 cm, mass: 65·3 ± 12·3 kg) undertook maximal incremental exercise tests on a conventional arm crank ergometer. Age‐adjusted maximal heart rate was calculated using prediction equations based on leg exercise and compared with measured HRMAX data for the arms. Maximal HR for arm exercise was significantly overpredicted compared with age‐adjusted prediction equations in both young and older adults. Subtracting 10–20 beats min?1 from conventional prediction equations provides a reasonable estimate of HRMAX for upper body exercise in healthy older and younger adults. 相似文献
994.
Pharmacological differentiation of postsynaptic alpha adrenoceptors in the dog saphenous vein 总被引:1,自引:0,他引:1
P J Fowler M Grous W Price W D Matthews 《The Journal of pharmacology and experimental therapeutics》1984,229(3):712-718
The dog saphenous vein has postsynaptic subpopulations of both alpha-1 and alpha-2 adrenoceptors which are easily demonstrable using selective agonists and antagonists. Specific alpha-1 (methoxamine and SK&F 89748) or mixed alpha-1, alpha-2 (l-norepinephrine and M7) agonists as well as the specific alpha-2 agonist, BHT 920, cause concentration-related contraction of this tissue. However, maximum contractions produced by alpha-2 activation are significantly less than maximum contractions produced by alpha-1 or combined alpha-1, alpha-2 adrenoceptor activation. SK&F 89748-induced contractions are competitively inhibited by prazosin (pA2 = 7.74) and rauwolscine (pA2 = 6.63); BHT 920-induced contractions are unaffected by prazosin but inhibited by rauwolscine (pA2 = 8.93). Contractile responses to l-norepinephrine are inhibited by prazosin, rauwolscine or phenoxybenzamine in a manner that suggests that norepinephrine interacts with two subtypes of alpha adrenoceptors in this tissue. These data indicate that the dog saphenous vein strip is a suitable in vitro preparation for study of drug action at both postsynaptic adrenoceptors inasmuch as either subpopulation of alpha adrenoceptor can be studied independently using specific agonists or antagonists. 相似文献
995.
S Standing C P Price 《Clinica chimica acta; international journal of clinical chemistry》1976,66(3):393-403
Long-term treatment of rats with insulin does not influence the yield of the Golgi membrane-rich fraction obtained by Fleischers' method or the activity of galactosyl transferase (EC 2.4.1.38) present in this fraction. Exogenous insulin increases the total levels of the seromucoid and serum middle-weight molecular glycopeptide fraction, but does not alter the proportions of neutral sugars bound with the peptide residues of both fractions. 相似文献
996.
B G Ellis S M Tucker A E Thompson R G Price 《Clinica chimica acta; international journal of clinical chemistry》1975,64(2):195-202
1. The A, B, I1 and I2 forms of N-acetyl-beta-glucosaminidase present in urine, serum, kidney, liver and cerebral spinal fluid were separated on DEAE-cellulose and their presence confirmed by cellogel electrophoresis. The relative activities of each enzyme were determined by integrating the area under the elution peaks. 2. Serum A-form was eluted at a lower molarity of chloride than liver A-form and this was designated the As-form to distinguish it from the A-form of N-acetyl-beta-glucosaminidase found in liver and kidney. 3. The P-form of N-acetyl-beta-glucosaminidase present in the serum of a group of pregnant women was not detectable in urine samples from the same women. 4. Urinary NAG activities were found to be abnormally high in patients with impaired renal function. 5. The activity of both N-acetyl-beta-glucosaminidases A and B increased in pathological urines. The higher the total N-acetyl-beta-glucosaminidase activity excreted the higher the % of activity of the B-form present. 6. In a number of patients with haematuria an A-form similar to the serum As-form was present in the urine. 相似文献
997.
Sluka KA Radhakrishnan R Benson CJ Eshcol JO Price MP Babinski K Audette KM Yeomans DC Wilson SP 《Pain》2007,129(1-2):102-112
Peripheral initiators of muscle pain are virtually unknown, but likely key to development of chronic pain after muscle insult. The current study tested the hypothesis that ASIC3 in muscle is necessary for development of cutaneous mechanical, but not heat, hyperalgesia induced by muscle inflammation. Using mechanical and heat stimuli, we assessed behavioral responses in ASIC3-/- and ASIC3+/+ mice after induction of carrageenan muscle inflammation. ASIC3-/- mice did not develop cutaneous mechanical hyperalgesia after muscle inflammation when compared to ASIC3+/+ mice; heat hyperalgesia developed similarly between groups. We then tested if the phenotype could be rescued in ASIC3-/- mice by using a recombinant herpes virus vector to express ASIC3 in skin (where testing occurred) or muscle (where inflammation occurred). Infection of mouse DRG neurons with ASIC3-encoding virus resulted in functional expression of ASICs. Injection of ASIC3-encoding virus into muscle or skin of ASIC3-/- mice resulted in ASIC3 mRNA in DRG and protein expression in DRG and the peripheral injection site. Injection of ASIC3-encoding virus into muscle, but not skin, resulted in development of mechanical hyperalgesia similar to that observed in ASIC3+/+ mice. Thus, ASIC3 in primary afferent fibers innervating muscle is critical to development of hyperalgesia that results from muscle insult. 相似文献
998.
Charybdotoxin inhibits proliferation and interleukin 2 production in human peripheral blood lymphocytes. 总被引:11,自引:1,他引:11 下载免费PDF全文
M Price S C Lee C Deutsch 《Proceedings of the National Academy of Sciences of the United States of America》1989,86(24):10171-10175
We demonstrate that blockade of the lymphocyte voltage-gated K+ channel by charybdotoxin (CTX) inhibits lymphocyte mitogenesis. Charybdotoxin blocks conductance with a Ki of 0.3 nM and inhibits mitogen- and antigen-stimulated proliferation with a Ki of 0.5 nM. As opposed to the other blockers of the lymphocyte K+ channel, the inhibition of mitogenesis by CTX can be overcome selectively by exogenous recombinant interleukin 2 (IL-2); endogenous levels of IL-2 in the culture supernatants of stimulated cells are decreased by the presence of CTX. Our results suggest that the voltage-gated K+ channel is either directly or indirectly involved in IL-2 synthesis and/or secretion. 相似文献
999.
Phenotype-associated changes in the effects of 1,25-dihydroxyvitamin D3 on alkaline phosphatase and bone GLA-protein of rat osteoblastic cells 总被引:2,自引:0,他引:2
The effects of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] on alkaline phosphatase (AP) activity and the synthesis of gamma-carboxy-glutamic acid containing protein (BGP) were compared in phenotypically distinct cloned cell lines derived from the osteoblast-like rat osteogenic sarcoma line ROS 17/2-8. 1,25(OH)2D3 stimulated AP activity and BGP synthesis in phenotypes which exhibited relatively low basal AP activity and high basal BGP levels. In contrast 1,25(OH)2D3 inhibited AP activity in phenotypes that exhibited high basal AP activity. The latter cells had undetectable BGP levels and the synthesis of this protein failed to respond to the 1,25(OH)2D3 stimulus. In the cells that responded to 1,25(OH)2D3 with an increase in AP activity the effect of the hormone on AP could be blocked by actinomycin-D. However in the cells that responded to 1,25(OH)2D3 with inhibition of AP the effect of the hormone on AP was not influenced by actinomycin-D. The directly opposite effects of 1,25(OH)2D3 on the AP activity of the respective clones did not change qualitatively at different stages of culture and could not be accounted by differences in the 1,25(OH)2D3 receptor status nor by different effects of the hormone on cell proliferation. These data raise the possibility that the response of AP to 1,25(OH)2D3 in osteoblastic cells depends on their state of phenotypic differentiation. The stimulatory effect of the hormone in low AP-producing cells might be related to differentiation promoting properties of 1,25(OH)2D3. The inhibitory effect of 1,25(OH)2D3 on AP, unlike the stimulatory effect of the hormone does not appear to be mediated by the classical mechanism of 1,25(OH)2D3 action on the genome and might be associated with dedifferentiated osteoblastic cells. 相似文献