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Disordered small intestinal motility: a rational basis for toddlers'' diarrhoea 总被引:2,自引:1,他引:2 下载免费PDF全文
Toddler diarrhoea is the commonest cause of chronic diarrhoea without failure to thrive in childhood, but its pathogenesis remains obscure. We have studied upper small intestinal motility in three groups of children (control group 1 - children with no intestinal pathology undergoing duodenal intubation, n = 6; control group 2 - children with gastrointestinal pathology other than toddler diarrhoea, n = 11; control group 3 - children with toddler diarrhoea, n = 8). We studied fasting motor patterns and the response of the migrating motor complex to intravenous cholecystokinin and an intraduodenal bolus of 5% dextrose. The characteristics of the migrating motor complex in the three groups did not differ but their response to dextrose did. Intraduodenal dextrose disrupted the migrating motor complex in four out of four children in group 1; seven out of nine children in group 2; and nil of eight children with toddler diarrhoea in group 3. We suggest that this failure of intestinal motor response may play a major role in the pathogenesis of the diarrhoea in this condition. 相似文献
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Megan R. Schwarzman Janet M. Ackerman Shanaz H. Dairkee Suzanne E. Fenton Dale Johnson Kathleen M. Navarro Gwendolyn Osborne Ruthann A. Rudel Gina M. Solomon Lauren Zeise Sarah Janssen 《Environmental health perspectives》2015,123(12):1255-1264
Background
Current approaches to chemical screening, prioritization, and assessment are being reenvisioned, driven by innovations in chemical safety testing, new chemical regulations, and demand for information on human and environmental impacts of chemicals. To conceptualize these changes through the lens of a prevalent disease, the Breast Cancer and Chemicals Policy project convened an interdisciplinary expert panel to investigate methods for identifying chemicals that may increase breast cancer risk.Methods
Based on a review of current evidence, the panel identified key biological processes whose perturbation may alter breast cancer risk. We identified corresponding assays to develop the Hazard Identification Approach for Breast Carcinogens (HIA-BC), a method for detecting chemicals that may raise breast cancer risk. Finally, we conducted a literature-based pilot test of the HIA-BC.Results
The HIA-BC identifies assays capable of detecting alterations to biological processes relevant to breast cancer, including cellular and molecular events, tissue changes, and factors that alter susceptibility. In the pilot test of the HIA-BC, chemicals associated with breast cancer all demonstrated genotoxic or endocrine activity, but not necessarily both. Significant data gaps persist.Conclusions
This approach could inform the development of toxicity testing that targets mechanisms relevant to breast cancer, providing a basis for identifying safer chemicals. The study identified important end points not currently evaluated by federal testing programs, including altered mammary gland development, Her2 activation, progesterone receptor activity, prolactin effects, and aspects of estrogen receptor β activity. This approach could be extended to identify the biological processes and screening methods relevant for other common diseases.Citation
Schwarzman MR, Ackerman JM, Dairkee SH, Fenton SE, Johnson D, Navarro KM, Osborne G, Rudel RA, Solomon GM, Zeise L, Janssen S. 2015. Screening for chemical contributions to breast cancer risk: a case study for chemical safety evaluation. Environ Health Perspect 123:1255–1264; http://dx.doi.org/10.1289/ehp.1408337 相似文献46.
Borkowsky W Wara D Fenton T McNamara J Kang M Mofenson L McFarland E Cunningham C Duliege AM Francis D Bryson Y Burchett S Spector SA Frenkel LM Starr S Van Dyke R Jimenez E 《The Journal of infectious diseases》2000,181(3):890-896
Children of mothers infected with human immunodeficiency virus type 1 (HIV-1) were immunized at birth and at 1, 3, and 5 months with 1 of 3 doses of recombinant gp120 vaccines prepared from SF-2 or MN strains of HIV-1. A total of 126 children were not infected; 21 received adjuvant only. Vaccine recipients developed lymphoproliferative responses on >/=2 occasions, responding more often to homologous HIV-1 antigens than did adjuvant recipients (56% vs. 14%; P<.001). Responses were appreciated after 2 immunizations and were maintained for >84 weeks after the last immunization. An accelerated immunization schedule (birth, 2 weeks, 2 months, and 5 months) with the lowest dose of the SF-2 vaccine produced responses in all 11 vaccinees by 4 weeks. Responses to heterologous envelope antigens were also detected. Immune responses to vaccination are achievable at an age when some infection (perinatal or breast milk exposure related) may be prevented. 相似文献
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Rogstad KE Simms I Fenton KA Edwards S Fisher M Carne CA;British Cooperative Clinical Group of the British Association for Sexual Health HIV 《International journal of STD & AIDS》2005,16(5):348-352
New diagnoses of syphilis in the UK increased eight-fold between 1997 and 2002. This study, conducted in 2002, demonstrated that 31% of clinics were not confident of their expertise to obtain an adequate specimen for dark ground microscopy (DGM), and 35% were not confident of their expertise to detect treponemes on DGM. In all, 64% of clinics had observed adherence problems in HIV-positive patients treated with parenteral regimens, as against 42% with oral regimens. Also, 51% of clinics waited more than a week for the results of initial serological tests for syphilis, and 88% of clinics waited more than a week for confirmatory test results. Other concerns include the failure to perform syphilis serology consistently whenever HIV-positive patients were at risk, and the widespread use of doxycycline as a therapy for syphilis in HIV-positive patients despite concerns that this is not known to be fully treponemicidal in cerebrospinal fluid. 相似文献
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Deborah J. Jones Rex Forehand Jessica Cuellar Carlye Kincaid Justin Parent Nicole Fenton Nada Goodrum 《Clinical psychology review》2013,33(2):241-252
Disruptive behaviors of childhood are among the most common reasons for referral of children to mental health professionals. Behavioral parent training (BPT) is the most efficacious intervention for these problem behaviors, yet BPT is substantially underutilized beyond university research and clinic settings. With the aim of addressing this research-to-practice gap, this article highlights the considerable, but largely unrealized, potential for technology to overcome the two most pressing challenges hindering the diffusion of BPT: (1). The dearth of BPT training and supervision opportunities for therapists who work with families of children with disruptive behaviors; and (2). The failure to engage and retain families in BPT services when services are available. To this end, this review presents a theoretical framework to guide technological innovations in BPT and highlights examples of how technology is currently being harnessed to overcome these challenges. This review also discusses recommendations for using technology as a delivery vehicle to further advance the field of BPT and the potential implications of technological innovations in BPT for other areas of children's mental health are discussed. 相似文献
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Aging reduces the cardioprotective effect of ischemic preconditioning in the rat heart 总被引:4,自引:0,他引:4
Fenton RA Dickson EW Meyer TE Dobson JG 《Journal of molecular and cellular cardiology》2000,32(7):1371-1375
Multiple brief periods of ischemia in the mammalian heart elicits protection against morphologic and functional damage caused by longer-duration ischemia. Preconditioning-induced protection against post-ischemic contractile dysfunction has been reported to be depressed with aging of the adult heart. This study was undertaken to determine whether aging of the adult myocardium reduces the preconditioning-induced attenuation of necrosis observed with ischemia. Isolated, perfused hearts obtained from Fischer 344 rats of either 3 (young) or 22 (aged) months of age were paced and instrumented for determination of developed left ventricular pressure. Necrosis was determined with triphenyltetrazolium. In the absence of preconditioning, young and aged adult hearts made globally ischemic for 45 min developed necrosis involving 53+/-6% and 49+/-6% of the myocardium, respectively. Contractile function (+dP/dt(max)) at 90 min of reperfusion was depressed by 80% in young and 52% in aged hearts, compared to values obtained prior to preconditioning. Preconditioning with two 5 min ischemia/5 min reperfusion cycles significantly reduced necrosis development and enhanced reperfusion contractile function in young hearts. However, in aged adult hearts, the preconditioning did not significantly reduce the development of necrosis or enhance reperfusion contractile function. These data suggest that aging reduces the effectiveness of preconditioning in providing cardioprotection against ischemic-induced myocardial necrosis. 相似文献
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