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991.
R. W. Nelson M. Nipper A. Lawrence S. Watts 《Bulletin of environmental contamination and toxicology》2010,84(1):71-75
The role of echinoid parental nutrition in early-life stage toxicity is not well understood. Arbacia punctulata were fed either a fresh diet consisting of organic lettuce and carrots or a dry feed. Embryos from parents fed the dry feed
exhibited lower sensitivity to copper, whereas the opposite occurred with 1,3,5-trinitrobenzene and sodium dodecyl sulfate
(SDS). EC50 values for the dry and fresh feed treatments, respectively, were 41.0 and 29.9 μg/L for copper, 0.5 and 1.8 mg/L for 1,3,5-trinitrobenzene,
and 3.5 and 5.6 mg/L for SDS. The data suggests that nutritional standardization for sea urchins in ecotoxicological laboratories
needs to be addressed and further investigated. 相似文献
992.
Nicole C. Arrigo A. Paige Adams Douglas M. Watts Patrick C. Newman Scott C. Weaver 《Emerging infectious diseases》2010,16(9):1373-1380
Eastern equine encephalitis virus (EEEV; family Togaviridae, genus Alphavirus) is an arbovirus that causes severe disease in humans in North America and in equids throughout the Americas. The enzootic transmission cycle of EEEV in North America involves passerine birds and the ornithophilic mosquito vector, Culiseta melanura, in freshwater swamp habitats. However, the ecology of EEEV in South America is not well understood. Culex (Melanoconion) spp. mosquitoes are considered the principal vectors in Central and South America; however, a primary vertebrate host for EEEV in South America has not yet been identified. Therefore, to further assess the reservoir host potential of wild rodents and wild birds, we compared the infection dynamics of North American and South American EEEV in cotton rats (Sigmodon hispidus) and house sparrows (Passer domesticus). Our findings suggested that each species has the potential to serve as amplification hosts for North and South America EEEVs. 相似文献
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995.
Serious staphylococcal infections frequently begin in the skin. The present study used a mouse model of such infections to evaluate the ability of Staphylococcus aureus to disseminate from the skin and to determine if cutaneous damage from the infections was required for dissemination. The mice were inoculated with S. aureus onto flank skin prepared by a tape-stripping method that caused minimal disruption of the epidermal keratinocyte layers. After these inoculations the staphylococci were found to disseminate to the spleen and kidneys of almost all animals within 6 h. Induction of leucopenia did not affect this process. Cutaneous damage was prominent in these experimental infections and included loss of the epidermis, neutrophil infiltration into the epidermis, and complete necrosis of the dermis. The latter also occurred in cyclophosphamide-treated animals, indicating that the organisms themselves and not the host inflammatory responses were responsible. Dermal necrosis did not develop until 48 h after inoculation, a time by which dissemination had already occurred. Therefore, in this mouse model system S. aureus is capable of penetrating the epidermal keratinocyte layers and disseminating rapidly after inoculation; the experimental infections do produce significant dermal damage, but the latter develops after dissemination has already taken place. 相似文献
996.
Purpose With an incidence rate of 300 cases per 100000 population per year, Australia has the highest incidence of cutaneous squamous cell carcinoma (SCC) in the world. Metastatic cutaneous SCC in parotid lymph nodes are aggressive tumours with poor outcomes both in terms of local control and survival. Methodology This study reports a prospective series of 41 consecutive patients with metastatic SCC to the parotid gland in a major teaching hospital in Western Australia over a six‐year period from January 2000 to December 2005. Epidemiological, clinical, histopathological and treatment details along with patterns of failure were extracted from the database. The survival and failure curves were calculated using the Kaplan‐Meier method. Univariate and multivariate analysis were performed using Cox regression method. Results The five‐year absolute survival is 34.2% and the cancer specific survival 39.5%. Local failure was observed in 11 patients for an actuarial rate of local disease free survival of 65.8% at 6 years. Distant failure occurred in two patients for an actuarial distant disease free survival of 89.5% at 6 years. Both univariate and multivariate analysis failed to find any predictors of local or distant failure with statistical significance. Conclusions Multimodality treatment will still fail to locally control or cure at least a third of patients. Previously identified risk factors were not substantiated in this study and may relate to patient numbers. Parotidectomy and post‐operative radiotherapy remain the gold standard. Unlike their cutaneous counter parts metastatic SCC to the parotid gland remains an aggressive tumour with current treatment regimes. 相似文献
997.
An unusual cause of blindness in Wegener's granulomatosis. 总被引:2,自引:2,他引:0
998.
Josephine Swanton Robert Simister Daniel Altmann Hilary Watts Richard Keen John S Duncan Matthias J Koepp 《Seizure》2007,16(6):538-541
Bone mineral density (BMD) and content (BMC) were measured in 208 institutionalised patients with refractory epilepsy. BMD was in the osteoporotic range in 43% of males and 21% of females. BMC was reduced only in male patients. Apart from age and gender, no other factor or specific AED was particularly associated with reduced BMD or BMC. This study indicates the magnitude of the problem of bone disease in refractory epilepsy, in particular affecting young and male patients with chronic epilepsy. 相似文献
999.
1000.
Lianna Ishihara Rachel A Gibson Liling Warren Rim Amouri Kelly Lyons Catherine Wielinski Christine Hunter Jina E Swartz Ramu Elango P Anthony Akkari David Leppert Linda Surh Kevin H Reeves Siwan Thomas Leigh Ragone Nobutaka Hattori Rajesh Pahwa Joseph Jankovic Martha Nance Alan Freeman Neziha Gouider-Khouja Mounir Kefi Mourad Zouari Samia Ben Sassi Samia Ben Yahmed Ghada El Euch-Fayeche Lefkos Middleton David J Burn Ray L Watts Faycal Hentati 《Movement disorders》2007,22(1):55-61
Mutations in the leucine-rich repeat kinase-2 gene (LRRK2) are responsible for some forms of familial as well as sporadic Parkinson's disease (PD). The purpose of this study was to examine the frequency of a single pathogenic mutation (6055G > A) in the kinase domain of this gene in United States and Tunisian familial PD and to compare clinical characteristics between patients with and without the mutation. Standardized case report forms were used for clinical and demographic data collection. We investigated the frequency of the most common substitution of LRRK2 (G2019S, 6055G>A) and its impact on epidemiological and phenotypic features. The frequency of mutations in Tunisian families was 42% (38/91) and in U.S. families 2.6% (1/39), with the unique opportunity to compare homozygous (n = 23) and heterozygous (n = 109) Tunisian carriers of G2019S substitutions. Individuals with G2019S substitutions had an older age at onset but few other differences compared with families negative for the substitution. Patients with LRRK2 mutations had typical clinical features of PD. Comparisons between individuals with heterozygous and homozygous LRRK2 mutations suggested that gene dosage was not correlated with phenotypic differences; however, the estimated penetrance was greater in homozygotes across all age groups. 相似文献