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991.
Ojopi EP Cavalli LR Cavalieri LM Squire JA Rogatto SR 《Cancer Genetics and Cytogenetics》2002,134(2):123-126
Comparative genomic hybridization (CGH) analysis was performed for the identification of chromosomal imbalances in two benign gynecomastias and one malignant breast carcinoma derived from patients with male breast disease and compared with cytogenetic analysis in two of the three cases. CGH analysis demonstrated overrepresentation of 8q in all three cases. One case of gynecomastia presented gain of 1p34.3 through pter, 11p14 through q12, and 17p11.2 through qter, and loss of 1q41 through qter and 4q33 through qter. The other gynecomastia presented del(1)(q41) as detected by both cytogenetic and CGH analysis. CGH analysis of the invasive ductal carcinoma confirmed a gain of 17p11.2 through qter previously detected by cytogenetic analysis. These regions showed some similarity in their pattern of imbalance to the chromosomal alterations described in female and male breast cancer. 相似文献
992.
Roman T Schmitz M Polanczyk GV Eizirik M Rohde LA Hutz MH 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2003,(1):116-120
Attention-Deficit/Hyperactivity Disorder (ADHD) is a complex childhood-onset psychiatric disorder characterized by marked symptoms of inattention, hyperactivity, and impulsivity. The role of genetic factors in its etiology is strongly supported by family, adoption, and twin studies. Although most of the molecular studies have investigated the dopamine D4 receptor gene (DRD4) and the dopamine transporter gene (DAT1) genes in its etiology, pharmacological and brain imaging evidences seem to indicate that genes of the adrenergic system could also be attractive for association studies. We investigated a sample of 96 Brazilian ADHD children and adolescents and their parents for the ADRA2A MspI polymorphism. Although no association with either MspI allele was observed through the haplotype relative risk (HRR) analysis, effects of the ADRA2A gene on inattention and combined (inattention + hyperactivity/impulsivity) symptom scores were detected (U = 222.5, z = 2.19, P = 0.03; and U = 208.5, z = 2.32, P = 0.02, respectively). Our results suggest that the ADRA2A gene might have a small effect on ADHD susceptibility or that this gene might modulate the severity of the disorder. They are also consistent with the noradrenergic theories of ADHD, suggesting a role for the alpha2A adrenergic receptors in the disorder. 相似文献
993.
Mara Marga Alla Denisova Artur Sochnev Valdis Pirags Nadir R. Farid 《American journal of medical genetics. Part A》2001,102(2):188-191
Recent studies of Graves disease (GD) employing genome scanning techniques excluded the major histocompatibility complex as a contributor to disease liability. These findings contradict earlier population association studies. Our own earlier studies have also emphasized that genetic variation in human populations may give novel clues to disease liability and manifestations. To this end, we studied HLA class II alleles in 47 Latvian GD patients and 111 matched healthy controls. As expected, we found that DRB1*03 and DQA1*0501 (OR = 3.6, P = 0.029 and OR 2.35, P = 0.0373, respectively) were associated with GD. Unforeseen, DRB1*04 was found to be significantly increased in the patients compared to controls (OR 3.267, corrected P = 0.0319). The two DRB1 alleles conferred two non‐overlapping and independent susceptibilities to GD, in that only three patients were positive for both alleles, and the removal of each allele in turn resulted in only the other DRB1 allele showing significant association with the disease. There was no heterogeneity between the two patient groups (DRB1*03 positive and DRB1*04 positive) in clinical characteristics or disease manifestations. The phenotype DRB1*03 and/or DRB1*04 was found in 34/47 patients compared to 27/111 controls yielding an OR of 7.395 (P corrected = 0.000019). We examined the structural basis of DRB1 susceptibility to GD in light of this and previous studies, showing that DRB1*03, 04, and 08 were positively associated with the disease, whereas DRB1*07 was negatively associated. Differences in protein sequences were noted at residues 54, 57, 59, and 66; positions 54, 57, and 66 are on the same face of the α helix. The canonical arginine 54 is replaced by glutamine in DRB1*07. At position 66, asparagine in DRB1*03 and tyrosine in DRB1*04 are replaced by phenylalanine in DRB1*07. Residue 59, likely involved in pocket formation in the antigen binding groove, is modified by replacement of tyrosine in DRB1*03, 08, and 04 and by leucine in DRB1*07. The predicted differences in the shape and charges of the proximal reaches of the antigen binding groove between DRB1*07, and 03, 04, and 08, could determine whether or not a peptide from an auto‐antigen would be bound or not. Genetic variation among human populations may yield important clues to specific disease liability. © 2001 Wiley‐Liss, Inc. 相似文献
994.
Tatarciuc M Panaite S Neumann CP Mârţu S Viţalariu A Aanicăi C Ciobanu O 《Revista medico-chirurgical?? a Societ????ii de Medici ??i Naturali??ti din Ia??i》2000,104(4):141-145
The stress quantification in dento-periodontal structures is an important concept, as stress in the tissue and in surrounding structures. A number of clinical studies have suggested figures for such an optimal stress strange. The clinical experiments can be completed with mathematical analysing methods as finite element method. Once the basics of biomechanics understood laws the treatment goes clearly defined, the computer aided design improve the optimal restorative prosthetic or orthodontic appliance. The finite element method (FEM) makes possible the numerical simulation of different clinical situations. Based upon mathematical modelling and extrapolation from experimental studies, practical conclusions can be drawn concerning the different types of forces and their subsequent induced relationship to the stresses. Clinical and histological experiments confirm the mathematical prediction offered by the FEM. 相似文献
995.
Pierre Charlebois Frank Vitaro Sylvie Normandeau Mara Brendgen Normand Rondeau 《The journal of primary prevention》2004,25(3):375-388
One of the challenges of preventive intervention is the retention ofparticipants. Retention has been especially problematic when interventionsrequire a long-term engagement of participants. Investigations to documentfactors that predict enrolment and retention in clinical or preventiveprograms focused mainly on socio-familial factors, parental and childcharacteristics, and the therapist–family relationship. To our knowledge,the contribution of trainers' behaviors on participants' persistence in along-term preventive intervention was never documented. Trainers'(n = 8) behaviors were videotaped during self-regulation andsocial skills training for disruptive boys (n = 58). Trainers' behavior wascoded by independent observers and classified in seven mutually exclusivecategories. Boys' total attendance in the program was used as the indicatorof persistence. Results indicated that trainers' individual contact with theboys was the best predictor of persistence in the program. 相似文献
996.
Konstantin H Dragnev Ian Pitha-Rowe Yan Ma W Jeffrey Petty David Sekula Bryan Murphy Mara Rendi Nanjoo Suh Neil B Desai Michael B Sporn Sarah J Freemantle Ethan Dmitrovsky 《Clinical cancer research》2004,10(7):2570-2577
PURPOSE: There is a need to identify cancer chemoprevention mechanisms. We reported previously that all-trans-retinoic acid (RA) prevented carcinogenic transformation of BEAS-2B immortalized human bronchial epithelial cells by causing G(1) arrest, permitting repair of genomic DNA damage. G(1) arrest was triggered by cyclin D1 proteolysis via ubiquitin-dependent degradation. This study investigated which chemopreventive agents activated this degradation program and whether cyclin E was also degraded. EXPERIMENTAL DESIGN: This study examined whether: (a) cyclin E protein was affected by RA treatment; (b) cyclin degradation occurred in derived BEAS-2B-R1 cells that were partially resistant to RA; and (c) other candidate chemopreventive agents caused cyclin degradation. RESULTS: RA treatment triggered degradation of cyclin E protein, and ALLN, a proteasomal inhibitor, inhibited this degradation. Induction of the retinoic acid receptor beta, growth suppression, and cyclin degradation were each inhibited in BEAS-2B-R1 cells. Transfection experiments in BEAS-2B cells indicated that RA treatment repressed expression of wild-type cyclin D1 and cyclin E, but ALLN inhibited this degradation. Mutation of threonine 286 stabilized transfected cyclin D1, and mutations of threonines 62 and 380 stabilized transfected cyclin E, despite RA treatment. Specific chemopreventive agents triggered cyclin degradation. Nonclassical retinoids (fenretinide and retinoid X receptor agonists) and a synthetic triterpenoid (2-cyano-3,12-dioxooleana-1,9-dien-28-oic acid) each suppressed BEAS-2B growth and activated this degradation program. However, a vitamin D3 analog (RO-24-5531), a cyclooxygenase inhibitor (indomethacin), and a peroxisome proliferator-activated receptor gamma agonist (rosiglitazone) each suppressed BEAS-2B growth, but did not cause cyclin degradation. BEAS-2B-R1 cells remained responsive to nonclassical retinoids and to 2-cyano-3,12-dioxooleana-1,9-dien-28-oic acid. CONCLUSIONS: Specific chemopreventive agents activate cyclin proteolysis. Yet, broad resistance did not occur after acquired resistance to a single agent. This provides a therapeutic rationale for combination chemoprevention with agents activating non-cross-resistant pathways. 相似文献
997.
Manuela Roldán-Pallarés MD PhD Roquel Rollín ScB Rosa Bernal ScB Ainhoa Ripodas ScB José Angel Marañón ScB Arturo Fernández-Cruz MD PhD Raquel Fernández-Durango MD PhD 《Annals of Ophthalmology》2004,36(1):24-28
Endothelin-1 is a potent vasoconstrictive and neural peptide functionally active in the eye. We demonstrated that the concentration
of immunoreactive endothelin-1 in subretinal fluid was higher in patients with proliferative vitreoretinopathy (PVR) vs. uncomplicated
retinal detachment. No differences in plasma concentrations of immunoreactive endothelin-1 were found. Intraocular synthesis
of endothelin-1 may play a role in the pathogenesis of PVR. 相似文献
998.
Carla Palma Luisa Minghetti Mara Astolfi Elena Ambrosini Francesca Ceccherini Silberstein Stefano Manzini Giulio Levi Francesca Aloisi 《Glia》1997,21(2):183-193
Following brain injury, astrocytes express receptors for cytokines and neuropeptides and secrete several regulatory mediators that have a well established role in inflammation, immunity, and tissue development or repair. To elucidate the role of substance P (SP), a neurotransmitter peptide of the tachykinin family, in inducing astrocyte secretory activities, we have examined the expression of SP receptors and the functional consequences of their activation in cultured astrocytes from the human embryonic brain or spinal cord. Radioligand binding studies revealed that only one type of SP receptors, the high affinity NK-1 receptor, was present on human astrocytes and that spinal cord astrocytes expressed about 6 times as many SP binding sites as brain astrocytes. Following SP treatment, a substantial inositol phosphate formation was observed in spinal cord astrocytes only. Stimulation of spinal cord astrocytes with SP alone did not induce secretion of cytokines [interleukin-6 (IL-6), granulocyte-macrophage-CSF, macrophage chemoattractant protein-1 or leukemia inhibitory factor] or prostaglandin E2 (PGE2). Interestingly, however, SP selectively potentiated the inducing effect of IL-1β on IL-6 and PGE2 secretion by spinal cord astrocytes without affecting the IL-1-β-evoked secretion of other cytokines. SP also enhanced the small inducing effect of tumor necrosis factor-α (TNF-α) on IL-6 and PGE2 secretion and that of transforming growth factor-β on PGE2 secretion. These results suggest that SP can enhance immunoregulatory and neurotrophic astroglial functions mediated by IL-6 and PGE2 by acting in concert with a set of cytokines whose cerebral expression has been reported during development and in a variety of diseases. GLIA 21:183–193, 1997. © 1997 Wiley-Liss, Inc. 相似文献
999.
Antonio Gilardi Massimo Ralli Andrea Colizza Arianna Di Stadio Daniela Messineo Mara Riminucci Alessandro Corsi Antonio Greco Marco de Vincentiis 《Clinical Case Reports》2022,10(1)
Hemangiomas are developmental vascular abnormalities that are common in the head and neck (60%), rare in the oral cavity, and uncommon in the tongue. A patient performed a multi‐parametric MRI, which characterized the lesion of his tongue, providing relevant information for diagnostic, therapeutic orientation, and realization of slight aggressive surgery with consequent excellent recovery. 相似文献
1000.
Maria Cecilia Cercato Elvira Colella Alessandra Fabi Isabella Bertazzi Barbara Giuseppa Giardina Paolo Di Ridolfi Mara Mondati Patrizia Petitti Liciano Bigiarini Virginia Scarinci Alessandro Franceschini Francesca Servoli Irene Terrenato Francesco Cognetti Giuseppe Sanguineti Cristina Cenci 《The Journal of international medical research》2022,50(2)
ObjectivesWe implemented narrative medicine in clinical practice using the Digital Narrative Medicine (DNM) platform.MethodsWe conducted a preliminary, open, uncontrolled, real-life study in the oncology and radiotherapy departments of Istituto di Ricovero e Cura a Carattere Scientifico National Cancer Institute Regina Elena, Rome, Italy. We recruited adult Italian-speaking patients who then completed the DNM diary from the start of treatment. The primary endpoint was DNM feasibility; secondary endpoints were health care professionals’ opinions about communication, therapeutic alliance, and information collection and patients’ opinions about therapeutic alliance, awareness, and coping ability. We used open- and closed-ended questions (scores 1 to 5) and a structured interview.ResultsThirty-one patients (67%) used the diary (84% women). Health care professionals’ mean scores for feasibility and utility were ≥4.0. Patients’ utility scores were related to health care professionals’ feedback regarding the narratives. The main advantages for health care professionals were the opportunity to obtain relevant patient data and to strengthen communication and patient relationships (mean scores 4.4–5.0). Both groups strongly encouraged introduction of the diary in clinical practice.ConclusionUse of the DNM in oncology patients assisted clinicians with understanding their patients experience. 相似文献