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991.
992.
C Agostoni E Riva R Bellù S Trojan D Luotti M Giovannini 《Journal of the American College of Nutrition》2013,32(6):658-663
To compare the effects of the exogenous supply of long-chain polyunsaturated fatty acids (LCP) and cholesterol on the lipid and fatty acid status in full-term, 4-month old infants.Twenty-three infants received a standard infant formula while twenty-one were given a formula enriched with LCP and cholesterol in a prospective, randomized study. The composition of the two formulas differed only in fat quality. A group of fifteen breastfed infants fed was used as reference. No one was complemented with solid foods before blood sampling at 4 months of life.Differences in total-cholesterol and low-density lipoprotein-cholesterol (LDL-C) levels between feeding groups were mainly gender-related. Dietary cholesterol tended to increase LDL-C plasma levels. The breastfed and the enriched formula-fed groups had higher levels of circulating LCP than the group that received the standard formula. In the erythrocytes of infants fed the standard formula, C22:6 n-3 levels were less than 50% those of the breastfed and the enriched formula-fed ones. Higher C20:4 n-6 levels were found in the erythrocytes of the enriched formula-fed group.Formula-fed, full-term infants maintain a lipid and fatty acid status close to that of breastfed infants when supplied with dietary LCP and cholesterol. 相似文献
993.
Teresa Gagliano Carlo Filieri Mariella Minoia Mattia Buratto Federico Tagliati Maria Rosaria Ambrosio Marcello Lapparelli Matteo Zoli Giorgio Frank Ettore degli Uberti Maria Chiara Zatelli 《Pituitary》2013,16(1):91-100
Dopamine (DA) therapy of non-functioning pituitary adenomas (NFA) can result in tumor stabilization and shrinkage. However, the mechanism of action is still unknown. Previous evidence showed that DA can inhibit pituitary vascular endothelial growth factor expression (VEGF), that may be involved in pituitary tumor growth. The aim of our study was to clarify whether VEGF secretion modulation might mediate the effects of DA agonists on cell proliferation in human NFA. We assessed DA receptor subtype 2 (DR2) expression in 20 NFA primary cultures, where we also investigated the effects of a selective DR2 agonist, cabergoline (Cab), on VEGF secretion and on cell viability. All NFA samples expressed α-subunit and DR2 was expressed in 11 samples. In DR2 expressing tumors, Cab significantly reduced cell viability (?25%; P < 0.05) and VEGF secretion (?20%; P < 0.05). These effects were counteracted by treatment with the DA antagonist sulpiride. Cab antiproliferative effects were blocked by VEGF. Our data demonstrate that Cab, via DR2, inhibits cell viability also by reducing VEGF secretion in a selected group of NFA, supporting that DA agonists can be useful in the medical therapy of DR2 expressing NFA. 相似文献
994.
G. Spalletta D.W. Morris F. Angelucci I.A. Rubino I. Spoletini P. Bria G. Martinotti A. Siracusano G. Bonaviri S. Bernardini C. Caltagirone P. Bossù G. Donohoe M. Gill A.P. Corvin 《European psychiatry》2010,25(6):311-313
Brain-derived neurotrophic factor (BDNF) gene variants may potentially influence behaviour. In order to test this hypothesis, we investigated the relationship between BDNF Val66Met polymorphism and aggressive behaviour in a population of schizophrenic patients. Our results showed that increased number of BDNF Met alleles was associated with increased aggressive behaviour. 相似文献
995.
Caruso G Caffo M Alafaci C Raudino G Cafarella D Lucerna S Salpietro FM Tomasello F 《Nanomedicine : nanotechnology, biology, and medicine》2011,7(6):744-752
Malignant brain tumors are difficult to manage clinically and are associated with high rates of morbidity and mortality. Late diagnosis and the limitations of conventional therapies that may result from inefficient delivery of the therapeutic or contrast agent to brain tumors due to the blood-brain barrier and nonspecificity of the agents, are major reasons for this unsolved clinical problem. Nanotechnology involves the design, synthesis, and characterization of materials and devices that have a functional organization in at least one dimension on the nanometer scale. The nanoparticle has emerged as a potential vector for brain delivery, able to overcome the difficulties of modern strategies. Moreover, multifunctionality can be engineered into a single nanoplatform so that it can provide tumor-specific detection, treatment, and follow-up monitoring. This review reports the latest research in nanoparticle-based glioma treatment. FROM THE CLINICAL EDITOR: In recent years, nanoparticles have emerged as potential delivery vectors targeting brain tumors, including multifunctional NP-s allowing tumor-specific detection, treatment, and follow-up monitoring. This review summarizes the latest research in nanoparticle-based glioma treatment. 相似文献
996.
Cutrona G Colombo M Matis S Reverberi D Dono M Tarantino V Chiorazzi N Ferrarini M 《European journal of immunology》2006,36(3):558-569
ZAP-70 is a protein tyrosine kinase initially found in T and NK cells. Recently, this important signaling element was detected in leukemic B cells from a subgroup of patients with B cell chronic lymphocytic leukemia (B-CLL). In this study, ZAP-70 was detected in normal B cells from human tonsils, but not from peripheral blood. The cDNA sequence of B cell ZAP-70 was the same as that in T cells. Germinal center B cells and plasma cells had a substantial proportion of ZAP-70+ cells, while memory and follicular mantle B cells, which contain low numbers of activated B cells, expressed relatively little ZAP-70. A cell fraction of IgD+, CD38+ B cells, which are comprised of many in vivo activated B cells, exhibited the highest levels of ZAP-70. Density gradient fractionation of tonsil B cells confirmed that ZAP-70 was not expressed by resting B cells, but was expressed by buoyant, in vivo activated B cells. In these B cells, the expression of ZAP-70 correlated with that of CD38 and not with that of CD5, a hallmark of B-CLL cells. B-CLL cells are activated cells and their ZAP-70 expression reflects a normal property of activated B cells populations rather than a neoplastic aberration. 相似文献
997.
Lugo-Chinchilla AM Báez D Vélez M Ildefonso C Renaud FL 《Journal of neuroimmunology》2006,176(1-2):86-94
Alterations in opioid signaling that take place in murine peritoneal macrophages in vitro are variably dependent on opiate exposure conditions. Acute exposure to morphine inhibits Fc-mediated phagocytosis by a pertussis toxin (PT)-sensitive mechanism, but has no effect on cAMP levels. In contrast, chronic exposure to morphine results in a "tolerant" state, wherein test and control values for both phagocytosis and cAMP are equivalent. However, drug withdrawal after chronic exposure to morphine results in inhibition of phagocytosis and a concomitant 4-fold increase in cAMP by a PT-insensitive mechanism. This increase is causally related to inhibition of phagocytosis since an artificial increase in cAMP inhibits phagocytosis in non-withdrawn cells exposed chronically to morphine. We suggest that macrophage opioid receptors signaling switches from a Gi/o-mediated mechanism that does not involve adenylate cyclase in acute exposure to a non-Gi/o-mediated adenylate cyclase superactivation during chronic exposure. 相似文献
998.
999.
Moreno JC Klootwijk W van Toor H Pinto G D'Alessandro M Lèger A Goudie D Polak M Grüters A Visser TJ 《The New England journal of medicine》2008,358(17):1811-1818
DEHAL1 has been identified as the gene encoding iodotyrosine deiodinase in the thyroid, where it controls the reuse of iodide for thyroid hormone synthesis. We screened patients with hypothyroidism who had features suggestive of an iodotyrosine deiodinase defect for mutations in DEHAL1. Two missense mutations and a deletion of three base pairs were identified in four patients from three unrelated families; all the patients had a dramatic reduction of in vitro activity of iodotyrosine deiodinase. Patients had severe goitrous hypothyroidism, which was evident in infancy and childhood. Two patients had cognitive deficits due to late diagnosis and treatment. Thus, mutations in DEHAL1 led to a deficiency in iodotyrosine deiodinase in these patients. Because infants with DEHAL1 defects may have normal thyroid function at birth, they may be missed by neonatal screening programs for congenital hypothyroidism. 相似文献
1000.
Roberto Esposito Filippo Cieri Piero Chiacchiaretta Nicoletta Cera Mariella Lauriola Massimo Di Giannantonio Armando Tartaro Antonio Ferretti 《Brain imaging and behavior》2018,12(1):127-141
Resting state brain activity incorporates different components, including the Default Mode Network and the Dorsal Attention Network, also known as task-negative network and task-positive network respectively. These two networks typically show an anticorrelated activity during both spontaneous oscillations and task execution. However modifications of this anticorrelated activity pattern with age and pathology are still unclear. The present study aimed to investigate differences in resting state Default Mode Network-Dorsal Attention Network functional anticorrelation among young adults, healthy elders and Mild Cognitive Impairment patients. We retrospectively enrolled in this study 27 healthy young adults (age range: 25–35 y.o.; mean age: 28,5), 26 healthy elders (age range: 61–72 y.o.; mean age: 65,1) and 17 MCI patients (age range 64–87 y.o.; mean age: 73,6). Mild Cognitive Impairment patients were selected following Petersen criteria. All participants underwent neuropsychological evaluation and resting state functional Magnetic Resonance Imaging. Spontaneous anticorrelated activity between Default Mode Network and Dorsal Attention Network was observed in each group. This anticorrelation was significantly decreased with age in most Default Mode Network-Dorsal Attention Network connections (p < 0.001, False Discovery Rate corrected). Moreover, the anticorrelation between the posterior cingulate cortex node of the Default Mode Network and the right inferior parietal sulcus node of the Dorsal Attention Network was significantly decreased when comparing Mild Cognitive Impairment with normal elders (p < 0.001, False Discovery Rate corrected). The functional connectivity changes in patients were not related to significant differences in grey matter content. Our results suggest that a reduced anticorrelated activity between Default Mode Network and Dorsal Attention Network is part of the normal aging process and that Mild Cognitive Impairment status is associated with more evident inter-networks functional connectivity changes. 相似文献