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571.
A.B. Schwartz Manigandan Lejeune Guilherme G. Verocai Rebecca Young Paul H. Schwartz 《Emerging infectious diseases》2021,27(7):1923
We report a case of autochthonous infection of the eye worm Thelazia callipaeda in a dog in the northeastern United States. Integrated morphologic identification and molecular diagnosis confirmed the species. Phylogenetic analysis suggested introduction from Europe. The zoonotic potential of this parasite warrants broader surveillance and increased awareness among physicians and veterinarians. 相似文献
572.
A 24-year-old woman had a 9-week history of second to third daily urticaria that began after an episode of contact urticaria to topical bufexamac. She was found to have an underlying gastrointestinal infection with Blastocystis hominis. This was thought to be clinically relevant as she had a history of mild chronic diarrhoea. After treatment of the Blastocystis hominis, her urticaria ceased. This could indicate the importance of performing stool microscopy and culture on all patients with chronic urticaria of unknown aetiology. The relationship of urticaria to intestinal parasites and the possibility that non-steroidal anti-inflammatory medications could act as cofactors that help precipitate an urticarial reaction is discussed. 相似文献
573.
Reconstructed micro computed tomography (Micro-CT, micro-CT) images have revealed the detailed three-dimensional structure of the cranium of human fetal congenital anomalies for the first time. The objects were a head and a cervix of female autosite and a parasite consisting of only a head conjoined to the scapular region of the autosite of an asymmetric double malformation (asymmetric conjoined twins, heteropagus twinning) at a gestational age of 8 months. The cranium of the autosite was normal, but that of the parasite was characterized by otocephaly (agnathia, synotia, and monorhina) and almost all the cranial bones were of an abnormal shape. It is suggested that a part of occipital bone (the basioccipital and exoccipital bones), the vomer and cribriform plate were absent and this resulted in the fusion and overlapping of bilateral temporal and craniofacial bones that should have been adjacent to them. This resulted in a reformation and relocation of most of the cranial bones. Micro-CT is a useful tool to visualize the detailed bone structure which has not been clarified by the conventional dissection methods and other imaging technologies and is a powerful instrument for studying congenital anomalies. 相似文献
574.
575.
Distinct DC subsets regulate adaptive Th1 and 2 responses during Trichuris muris infection
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Low‐ and high‐dose infections with the murine large intestinal nematode Trichuris muris are associated with induction of adaptive Th1 and Th2 responses, respectively, in mesenteric lymph nodes (MLN). Classical dendritic cells (cDC) accumulate in the large intestinal mucosa and MLN upon T. muris infection, yet their role in driving adaptive responses to infection remains largely unknown. We performed low‐ and high‐dose T. muris infections of mice deficient in defined cDC subsets to investigate their role in induction of adaptive immune responses. Mice lacking IRF4‐dependent cDC failed to clear a high‐dose infection and displayed impaired Th2 responses. Conversely, mice lacking IRF8‐dependent cDC cleared a low‐dose infection and displayed an impaired Th1 response while increased production of Th2 cytokines. Finally, mice lacking both IRF4‐ and IRF8‐dependent cDC were able to generate a Th2 response and clear a low‐dose infection. Collectively, these results suggest that IRF4‐ and IRF8‐dependent cDC act antagonistically during T. muris infection, and demonstrate that intestinal Th2 responses can be generated towards T. muris in the absence of IRF4‐dependent cDC. 相似文献
576.
577.
《Placenta》2014
Workshops are an important part of the IFPA annual meeting as they allow for discussion of specialised topics. At IFPA meeting 2013 there were twelve themed workshops, three of which are summarized in this report. These workshops related to various aspects of placental biology but collectively covered areas of placental function, cell turnover and immunology: 1) immunology; 2) novel determinants of placental cell fate; 3) dual perfusion of human placental tissue. 相似文献
578.
A Qualitative Meta-Analysis Reveals Consistent Effects of Atrazine on Freshwater Fish and Amphibians
Objective
The biological effects of the herbicide atrazine on freshwater vertebrates are highly controversial. In an effort to resolve the controversy, we conducted a qualitative meta-analysis on the effects of ecologically relevant atrazine concentrations on amphibian and fish survival, behavior, metamorphic traits, infections, and immune, endocrine, and reproductive systems.Data sources
We used published, peer-reviewed research and applied strict quality criteria for inclusion of studies in the meta-analysis.Data synthesis
We found little evidence that atrazine consistently caused direct mortality of fish or amphibians, but we found evidence that it can have indirect and sublethal effects. The relationship between atrazine concentration and timing of amphibian metamorphosis was regularly nonmonotonic, indicating that atrazine can both accelerate and delay metamorphosis. Atrazine reduced size at or near metamorphosis in 15 of 17 studies and 14 of 14 species. Atrazine elevated amphibian and fish activity in 12 of 13 studies, reduced antipredator behaviors in 6 of 7 studies, and reduced olfactory abilities for fish but not for amphibians. Atrazine was associated with a reduction in 33 of 43 immune function end points and with an increase in 13 of 16 infection end points. Atrazine altered at least one aspect of gonadal morphology in 7 of 10 studies and consistently affected gonadal function, altering spermatogenesis in 2 of 2 studies and sex hormone concentrations in 6 of 7 studies. Atrazine did not affect vitellogenin in 5 studies and increased aromatase in only 1 of 6 studies. Effects of atrazine on fish and amphibian reproductive success, sex ratios, gene frequencies, populations, and communities remain uncertain.Conclusions
Although there is much left to learn about the effects of atrazine, we identified several consistent effects of atrazine that must be weighed against any of its benefits and the costs and benefits of alternatives to atrazine use. 相似文献579.
Omumbo JA Hay SI Snow RW Tatem AJ Rogers DJ 《Tropical medicine & international health : TM & IH》2005,10(6):557-566
OBJECTIVES: Malaria risk maps have re-emerged as an important tool for appropriately targeting the limited resources available for malaria control. In Sub-Saharan Africa empirically derived maps using standardized criteria are few and this paper considers the development of a model of malaria risk for East Africa. METHODS: Statistical techniques were applied to high spatial resolution remotely sensed, human settlement and land-use data to predict the intensity of malaria transmission as defined according to the childhood parasite ratio (PR) in East Africa. Discriminant analysis was used to train environmental and human settlement predictor variables to distinguish between four classes of PR risk shown to relate to disease outcomes in the region. RESULTS: Independent empirical estimates of the PR were identified from Kenya, Tanzania and Uganda (n = 330). Surrogate markers of climate recorded on-board earth orbiting satellites, population settlement, elevation and water bodies all contributed significantly to the predictive models of malaria transmission intensity in the sub-region. The accuracy of the model was increased by stratifying East Africa into two ecological zones. In addition, the inclusion of urbanization as a predictor of malaria prevalence, whilst reducing formal accuracy statistics, nevertheless improved the consistency of the predictive map with expert opinion malaria maps. The overall accuracy achieved with ecological zone and urban stratification was 62% with surrogates of precipitation and temperature being among the most discriminating predictors of the PR. CONCLUSIONS: It is possible to achieve a high degree of predictive accuracy for Plasmodium falciparum parasite prevalence in East Africa using high-spatial resolution environmental data. However, discrepancies were evident from mapped outputs from the models which were largely due to poor coverage of malaria training data and the comparable spatial resolution of predictor data. These deficiencies will only be addressed by more random, intensive small areas studies of empirical estimates of PR. 相似文献
580.