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41.
42.
Marianne Quiding-Jrbrink Mekuria Lakew Inger Nordstrm Jacques Banchereau Eugene Butcher Jan Holmgren Cecil Czerkinsky 《European journal of immunology》1995,25(2):322-327
Circulating spontaneous antibody-secreting cells (ASC) induced by mucosal and systemic immunizations in human volunteers have been characterized with respect to differentiation stage and homing commitments. Irrespective of the immunization route, the large majority of ASC co-expressed CD19 and HLA-DR, which are normally lost during the transition of plasmablasts to plasmocytes, as well as CD38, a marker of activated B cell blasts, expressed also by plasmocytes. However, these cells expressed neither CD28, a molecule acquired by plasmocytes, nor CD22 and CD37, which are lost during the transition of plasmablasts to plasmocytes. Therefore, the large majority of ASC found in peripheral blood after oral and parenteral immunizations are terminally differentiated B cells, but not fully differentiated plasmocytes. As a whole, the mucosally derived ASC population seemed to be more homogenously differentiated. CD25 was detected on few ASC, whereas ASC expressing CD71 were more numerous, especially among systemically derived ASC. Almost all ASC expressed the adhesion molecules CD44 and α4-integrins, irrespective of immunization route. However, virtually all systemically derived ASC expressed L-selectin, recognizing the peripheral lymph node addressin, whereas only a minority of mucosally induced blood ASC expressed L-selectin. These studies are the first to demonstrate in humans that circulating precursors of mucosal B cell immunoblasts utilize organ-specific recognition mechanisms distinct from those of corresponding systemic B cells and appear to be more advanced in the B lineage maturation pathway. Specialization of receptor expression could explain both the unification of immune responses in diverse mucosal sites and the physiologic segregation of mucosal from non-mucosal immune mechanisms in humans. 相似文献
43.
Ines Santisteban Francisco X. Arredondo-Vega Susan Kelly Marianne Debre Alain Fischer Jean Louis Prignon Bettina Hilman Jane Eldahr David H. Dreyfus Erwin W. Gelfand P. Lynne Howell Michael S. Hershfield 《Human mutation》1995,5(3):243-250
Three new missense mutations (H15D, A83D, and A179D) and a new splicing defect (573 + 1G→A) in the 5′ splice site of intron 5 were among six mutant adenosine deaminase (ADA) alleles found in three unrelated patients with severe combined immunodeficiency disease, the most common phenotype associated with ADA deficiency. When expressed in vitro, the H15D, A83D, and A179D proteins lacked detectable ADA activity. The splicing defect caused skipping of exon 5, resulting in premature termination of translation and a reduced level of mRNA. H15D is the first naturally occurring mutation of a residue that coordinates directly with the enzyme-associated zinc ion. Molecular modeling based on the atomic coordinates of murine ADA suggests that the D15 mutation would create a cavity or gap between the zinc ion and the side chain carboxylate of D15. This could alter the ability of zinc to activate a water molecule postulated to play a role in the catalytic mechanism. A83 and A179 are not directly involved in the active site, but are conserved residues located respectively in a helix 4 and β strand 4 of the α/β barrel. Replacement of these small hydrophobic Ala residues with the charged, more bulky Asp side chain may distort ADA structure and affect enzyme stability or folding.© 1995 wiley-Liss, Inc. 相似文献
44.
Mats Fredrikson Tomas Danielssons Bernard T. Engel Marianne Frisk-Holmberg Gunnar Ström Örjan Sundin 《Psychophysiology》1985,22(2):167-174
The aim of the present research was to study individual response specificity in 22 male patients having essential hypertension (HT) and to compare these patients with age-matched male normotensive controls (NT). Four stimuli, letter identification, mental arithmetic, cold pressor and isometric exercise, were administered while recordings were made of: systolic and diastolic blood pressures, heart rate, respiration, forearm and hand blood flows, and skin conductance level and fluctuations. After each session urine samples were collected and epinephrine and norepinephrine levels were analyzed. Twelve subjects in the HT group were given beta-adrenergic blocking agents and retested 1 to 21 months (X?= 12 months) after the first session. Each response was standardized, using NT as the reference group. Intraclass correlations were computed to evaluate whether HT males reacted with a more consistent hierarchy of responses than did NT. Intraclass correlations were significantly higher among the patients than in the control group, regardless of whether the blood pressure response was included or excluded in the computation of the intraclass correlations. Thus, we conclude that male HT patients show more individual response specificity than NT controls. Beta-adrenergic receptor antagonists reduced levels of cardiovascular activity and attenuated reactivity but did not affect amount of specificity. Thus, intraclass correlations provide unique and useful information, since they are not related to blood pressure reactivity or to urinary catecholamine levels, nor affected by beta-adrenergic blockade. 相似文献
45.
Evidence that gamma/delta T cells play a broad, immunoregulatory role has been accumulating steadily. We show here that myeloid cells are disregulated after peritoneal infection with Listeria monocytogenes in mice lacking gamma/delta T cells. Inflammatory populations of neutrophils and monocytes recruited to the site of infection remained longer. Intracellular cytokine analysis showed that frequencies of myeloid cells producing interleukin-12 and tumor necrosis factor alpha were higher and remained elevated longer after infection in mice genetically deficient in gamma/delta T cells. In vivo dye-tracking studies indicated that the majority of inflammatory monocytes differentiated into resident tissue macrophages in situ. In vitro experiments confirmed that monocytes harvested from mice lacking gamma/delta T cells were defective in their maturation process. This evidence suggests that gamma/delta T cells promote differentiation in the monocyte/macrophage lineage. These cells are important for bactericidal activity, inflammatory cytokine production, clearance of inflammatory neutrophils, and ultimately, antigen presentation to T cells. Regulation of monocyte/macrophage differentiation may underlie a broad segment of the phenotypic alterations that have been reported in mice lacking gamma/delta T cells. 相似文献
46.
Dunø M Colding-Jørgensen E Grunnet M Jespersen T Vissing J Schwartz M 《European journal of human genetics : EJHG》2004,12(9):738-743
Mutations in the CLCN1 gene, encoding a muscle-specific chloride channel, can cause either recessive or dominant myotonia congenita (MC). The recessive form, Becker's myotonia, is believed to be caused by two loss-of-function mutations, whereas the dominant form, Thomsen's myotonia, is assumed to be a consequence of a dominant-negative effect. However, a subset of CLCN1 mutations can cause both recessive and dominant MC. We have identified two recessive and two dominant MC families segregating the common R894X mutation. Real-time quantitative RT-PCR did not reveal any obvious association between the total CLCN1 mRNA level in muscle and the mode of inheritance, but the dominant family with the most severe phenotype expressed twice the expected amount of the R894X mRNA allele. Variation in allelic expression has not previously been described for CLCN1, and our finding suggests that allelic variation may be an important modifier of disease progression in myotonia congenita. 相似文献
47.
48.
Genetic polymorphism of cytomegalovirus strains responsible of congenital infections 总被引:1,自引:0,他引:1
Picone O Costa JM Ville Y Chaix ML Rouzioux C Leruez-Ville M 《Pathologie-biologie》2004,52(9):534-539
OBJECTIVES: Congenital Cytomegalovirus (CMV) infection is the main cause of neurological handicap in young children. The objective for studying genetic polymorphism of strains responsible for congenital infection is to identify CMV strains or groups of strains which would be more frequent in this context and/or which would be responsible for more severe congenital infection. METHODS: In this paper, we report and analyze the literature concerning the genetic polymorphism of CMV strains responsible of congenital infection, in the genes coding for the envelop protein B and the non structural UL144 protein and in the CMV short tandem repeats. RESULTS AND CONCLUSION: All UL144 and gB genotypes can be vertically transmitted from mothers to fetuses, none of these studies has shown any link between the genotypes and the severity of congenital disease. Moreover, no link between short tandem repeats polymorphism and severity of congenital disease has been demonstrated. However, short tandem repeats analysis may be a powerful tool to study the epidemiology of CMV congenital infections. 相似文献
49.
Mai-Lei Woo Kinshella Shazmeen Omar Kerri Scherbinsky Marianne Vidler Laura A. Magee Peter von Dadelszen Sophie E. Moore Rajavel Elango The PRECISE Conceptual Framework Working Group 《Nutrients》2021,13(2)
The placenta is a vital, multi-functional organ that acts as an interface between maternal and fetal circulation during pregnancy. Nutritional deficiencies during pregnancy alter placental development and function, leading to adverse pregnancy outcomes, such as pre-eclampsia, infants with small for gestational age and low birthweight, preterm birth, stillbirths and maternal mortality. Maternal nutritional supplementation may help to mitigate the risks, but the evidence base is difficult to navigate. The primary purpose of this umbrella review is to map the evidence on the effects of maternal nutritional supplements and dietary interventions on pregnancy outcomes related to placental disorders and maternal mortality. A systematic search was performed on seven electronic databases, the PROSPERO register and references lists of identified papers. The results were screened in a three-stage process based on title, abstract and full-text by two independent reviewers. Randomized controlled trial meta-analyses on the efficacy of maternal nutritional supplements or dietary interventions were included. There were 91 meta-analyses included, covering 23 types of supplements and three types of dietary interventions. We found evidence that supports supplementary vitamin D and/or calcium, omega-3, multiple micronutrients, lipid-based nutrients, and balanced protein energy in reducing the risks of adverse maternal and fetal health outcomes. However, these findings are limited by poor quality of evidence. Nutrient combinations show promise and support a paradigm shift to maternal dietary balance, rather than single micronutrient deficiencies, to improve maternal and fetal health. The review is registered at PROSPERO (CRD42020160887). 相似文献
50.
Sina Schwarzkopf Adalbert Krawczyk Dietmar Knop Hannes Klump Andreas Heinold Falko M. Heinemann Laura Thümmler Christian Temme Marianne Breyer Oliver Witzke Ulf Dittmer Veronika Lenz Peter A. Horn Monika Lindemann 《Emerging infectious diseases》2021,27(1):122
We investigated immune responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among a group of convalescent, potential blood donors in Germany who had PCR-confirmed SARS-CoV-2 infection. Sixty days after onset of symptoms, 13/78 (17%) study participants had borderline or negative results to an ELISA detecting IgG against the S1 protein of SARS-CoV-2. We analyzed participants with PCR-confirmed infection who had strong antibody responses (ratio >3) as positive controls and participants without symptoms of SARS-CoV-2 infection and without household contact with infected patients as negative controls. Using interferon-γ ELISpot, we observed that 78% of PCR-positive volunteers with undetectable antibodies showed T cell immunity against SARS-CoV-2. We observed a similar frequency (80%) of T-cell immunity in convalescent donors with strong antibody responses but did not detect immunity in negative controls. We concluded that, in convalescent patients with undetectable SARS-CoV-2 IgG, immunity may be mediated through T cells. 相似文献