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101.
Changes in beta 2-adrenoceptor and other signaling proteins produced by chronic administration of 'beta-blockers' in a murine asthma model 总被引:1,自引:0,他引:1
Lin R Peng H Nguyen LP Dudekula NB Shardonofsky F Knoll BJ Parra S Bond RA 《Pulmonary pharmacology & therapeutics》2008,21(1):115-124
BACKGROUND: We have previously reported that chronic treatment with certain 'beta-blockers' reduces airway hyperresponsiveness (AHR) to methacholine in a murine model of asthma. METHODS: Airway resistance was measured using the forced oscillation technique in ovalbulmin-sensitized and ovalbulmin-challenged mice treated with several beta-adrenoceptor (beta-AR) ligands. We used the selective beta 2-AR ligand ICI 118,551 and the preferential beta 1-AR ligand metoprolol to investigate the receptor subtype mediating the beneficial effect. Expression of beta-ARs was evaluated using immunofluorescence. We evaluated several signaling proteins by western blot using lung homogenates, and measured the relaxation of the isolated trachea produced by EP2 and IP receptor agonists. RESULTS: Four findings were associated with the decreased AHR after chronic beta-blocker treatment: (1) the highly selective beta 2-AR antagonist/inverse agonist, ICI 118,551 produced the bronchoprotective effect; (2) beta 2-AR up-regulation resulted from chronic 'beta-blocker' treatment; (3) reduced expression of certain proteins involved in regulating bronchial tone, namely, Gi, phosphodiesterase 4D and phospholipase C-beta 1; and (4) an enhanced bronchodilatory response to prostanoid agonists for the IP and EP2 receptors. CONCLUSIONS: These data suggest that in the murine model of asthma, several compensatory changes associated with either increased bronchodilator signaling or decreased bronchoconstrictive signaling, result from the chronic administration of certain 'beta-blockers'. 相似文献
102.
Maisel A Mueller C Adams K Anker SD Aspromonte N Cleland JG Cohen-Solal A Dahlstrom U DeMaria A Di Somma S Filippatos GS Fonarow GC Jourdain P Komajda M Liu PP McDonagh T McDonald K Mebazaa A Nieminen MS Peacock WF Tubaro M Valle R Vanderhyden M Yancy CW Zannad F Braunwald E 《European journal of heart failure》2008,10(9):824-839
Natriuretic peptide (NP) levels (B-type natriuretic peptide (BNP) and N-terminal proBNP) are now widely used in clinical practice and cardiovascular research throughout the world and have been incorporated into most national and international cardiovascular guidelines for heart failure. The role of NP levels in state-of-the-art clinical practice is evolving rapidly. This paper reviews and highlights ten key messages to clinicians: 相似文献
103.
Morenike O. Folayan Carlos F. Cáceres Nadia A. Sam-Agudu Morolake Odetoyinbo Jamila K. Stockman Abigail Harrison 《AIDS and behavior》2017,21(9):2736-2745
Little is known about stressful triggers and coping strategies of Nigerian adolescents and whether or not, and how, HIV infection modulates these sources of stress and coping. This study evaluated differences in stressors and coping strategies among Nigerian adolescents based on HIV status. We analysed the data of six hundred 10–19 year old adolescents recruited through a population-based survey from 12 States of Nigeria who self-reported their HIV status. Data on stressors and coping strategies were retrieved by self-report from participants, using a validated structured questionnaire. We compared results between adolescents with and without HIV with respect to identification of specific life events as stressors, and use of specific coping strategies to manage stress. Logistic regression analysis adjusted for age and sex. Adolescents living with HIV (ALHIV) had significantly increased odds of identifying ‘having to visit the hospital regularly’ (AOR: 5.85; 95 % CI: 2.11–16.20; P = 0.001), and ‘having to take drugs regularly’ (AOR: 9.70; 95 % CI: 4.13–22.81; P < 0.001) as stressors; and ‘Seeking social support’ (AOR: 3.14; 95 % CI: 1.99–4.93; p < 0.001) and ‘using mental disengagement’ (OR: 1.64; 95 % CI: 0.49–1.84; p = 0.001) as coping strategies. Adolescents not living with HIV had significantly increased odds of identifying ‘argument with a friend or family member’ as a stressor (AOR: 6.59; 95 % CI: 3.62–11.98; P < 0.001). Life events related to adolescents’ HIV positive status were significant stressors for ALHIV. Providing targeted psychosocial support could help reduce the impact of such HIV status-related stressors on ALHIV. 相似文献
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Bougatef K Krichene A Marrakchi R Kourda N Blondeau Lahely Y Moussa A Troudi W Jileni SB Najjar T Soubrier F Ammar Elgaaied AB 《Gastroentérologie clinique et biologique》2007,31(12):1062-1066
Familial Adenomatous Polyposis (FAP) and Attenuated FAP (AFAP) are caused by a germline mutation in the Adenomatous polyposis coli (APC) gene. Recently, a new pathway characterized by a biallelic mutation in the MYH gene, with a recessive model of inheritance was discovered for this inherited syndrome. This report describes a Tunisian patient with an attenuated FAP phenotype, presenting seven colon polyps and an adenocarcinoma but no detectable germline mutations in the FAP target genes. A well known somatic mutation was found in the APC mutation cluster region (MCR). This case shows that further studies are needed to fully understand all the pathways of the FAP syndrome. 相似文献
105.
PG-M1: A New Monoclonal Antibody Directed against a Fixative-Resistant Epitope on the Macrophage-Restricted Form of the CD68 Molecule 总被引:9,自引:6,他引:9 下载免费PDF全文
Brunangelo Falini Leonardo Flenghi Stefano Pileri Marcello Gambacorta Barbara Bigerna Horst Durkop Florian Eitelbach Juergen Thiele Roberta Pacini Antonio Cavaliere Massimo Martelli Nadia Cardarelli Elena Sabattini Simonetta Poggi Harald Stein 《The American journal of pathology》1993,142(5):1359-1372
A new anti-macrophage monoclonal antibody (PG-M1) was produced by immunizing BALB/c mice with fresh spleen cells from a patient with Gaucher's disease. PG-M1 reacts strongly with a fixative-resistant epitope of an intracytoplasmic molecule, selectively expressed by virtually all macrophages of the human body. Although attempts to immunoprecipitate the molecule recognized by PG-M1 have failed so far, the reactivity of the antibody with COS-1 and WOP cells transfected with a human complementary DNA clone encoding for the CD68 antigen suggests that PG-M1 is a new member of the CD68 cluster. However, unlike other CD68 antibodies (KP1, EBM11, etc.), which react with both macrophages and myeloid cells, PG-M1 detects a fixative-resistant epitope on the macrophage-restricted form of the CD68 antigen. In 957 routinely fixed, paraffin-embedded samples, PG-M1 showed a more restricted reactivity with elements of the monocyte/macrophage lineage than the previously described monoclonal antibodies MAC-387 (anti-calgranulins), KP1 (CD68) and Ki-M1P. Among hematological malignancies, PG-M1 only labels acute leukemias of M4 and M5 type and rare examples of malignant histiocytosis/true histiocytic sarcoma. In contrast, acute leukemias of the M1, M2, M3, M6, M7, and L1-L3 types, non-Hodgkin's lymphomas, and Hodgkin and Reed-Sternberg cells of Hodgkin's disease are consistently PG-M1-negative. In the daily diagnostic practice, PG-M1 seems to be particularly valuable for the diagnosis of myelomonocytic or monocytic leukemia and neoplasms of true histiocytic origin in routine paraffin sections. 相似文献
106.
Kevin A. Michael John R. Paisey Bongani M. Mayosi Stephen Robinson Stuart Allen Nadia S. Sunni Paul R. Roberts John M. Morgan Gruschen R. Veldtman 《Journal of interventional cardiac electrophysiology》2008,23(3):229-233
INTRODUCTION: Late systemic right ventricular (RV) dysfunction after atrial redirection surgery is common. Patients may require cardiac transplantation in early adulthood. METHODS: We undertook cardiac resynchronisation (CRT)/defibrillator therapy in two patients as a bridge to transplantation. RESULTS: Two males (aged 24, 110 kg and 26 years, 106 kg); having undergone a Mustard procedure for dextro-transposition of the great arteries at 7 and 6 months of age respectively, presented with impaired systemic RV function and New York Heart Association III symptoms. Both patients had dual chamber pacemakers in-situ for sinus bradycardia. Upgrade to CRT was performed by conserving the existing endocardial leads and placement of epicardial electrodes. One demonstrated sustained improvement over a 24 month follow-up period. CONCLUSION: A hybrid CRT strategy is feasible in patients with failing systemic RVs and pre-existent endocardial dual chamber pacemakers. Appropriate patient selection criteria and optimum lead placement, however, still needs further evaluation in this population. 相似文献
107.
Juarez JG Harun N Thien M Welschinger R Baraz R Pena AD Pitson SM Rettig M DiPersio JF Bradstock KF Bendall LJ 《Blood》2012,119(3):707-716
CXCL12 and VCAM1 retain hematopoietic stem cells (HSCs) in the BM, but the factors mediating HSC egress from the BM to the blood are not known. The sphingosine-1-phosphate receptor 1 (S1P(1)) is expressed on HSCs, and S1P facilitates the egress of committed hematopoietic progenitors from the BM into the blood. In the present study, we show that both the S1P gradient between the BM and the blood and the expression of S1P(1) are essential for optimal HSC mobilization by CXCR4 antagonists, including AMD3100, and for the trafficking of HSCs during steady-state hematopoiesis. We also demonstrate that the S1P(1) agonist SEW2871 increases AMD3100-induced HSC and progenitor cell mobilization. These results suggest that the combination of a CXCR4 antagonist and a S1P(1) agonist may prove to be sufficient for mobilizing HSCs in normal donors for transplantation purposes, potentially providing a single mobilization procedure and eliminating the need to expose normal donors to G-CSF with its associated side effects. 相似文献
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