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891.
892.
Alejandro O Luquetti Suelene Brito do Nascimento Tavares Liliane da Rocha Siriano Rozangela Amaral de Oliveira Dayse Elizabeth Campos Cicilio Alves de Morais Enio Chaves de Oliveira 《Memórias do Instituto Oswaldo Cruz》2015,110(3):369-376
Transmission of Trypanosoma cruzi during pregnancy is estimated to
occur in less than 20% of infected mothers; however, the etiopathogenesis is not
completely understood. The Centre for Studies on Chagas Disease provides confirmation
of T. cruzi infection for individuals living in central Brazil.
In this retrospective hospital-based study, all requests for diagnosis of T.
cruzi infection in individuals less than 21 years old from 1994-2014 were
searched. We end with 1,211 individuals and their respective infected mothers.
Congenital transmission of infection was confirmed in 24 individuals (2%) in central
Brazil, an area where the main T. cruzi lineage circulating in
humans is TcII. This low prevalence of congenital Chagas disease is discussed in
relation to recent findings in the south region of Brazil, where TcV is the main
lineage and congenital transmission has a higher prevalence (approximately 5%),
similar to frequencies reported in Argentina, Paraguay and Bolivia. This is the first
report to show geographical differences in the rates of congenital transmission
of T. cruzi and the relationship between the prevalence of
congenital transmission and the type of Tc prevalent in each region. 相似文献
893.
894.
The occurrence of the fish Cephalopholis taeniops (Serranidae: Epinephelinae) has been recorded for the first time in the Canary Islands (eastern subtropical Atlantic). Repeated observations of adult stages of the species (??30?cm total length) inside oil platforms coming from the Gulf of Guinea greatly suggest an introduction related to the transport of ballast water in these structures, and show their importance in the dispersal of adult stages of large-sized species of littoral fish. Oil platforms constitute one special case in the introduction of marine species in the context of ballast water transport. This poorly known phenomenon may greatly favour marine species invasion, and might have significant repercussions in many regions -especially in the current climate change context- as well as explaining some surprising cases of occurrence of expatriated adult individuals of certain species. 相似文献
895.
Alexsander Augusto da Silveira Jackeline Santana Paula Andrade Ana Carla Peixoto Guissoni Adeliane Castro da Costa Arthur de Carvalho e Silva Heloisa Garcia da Silva Pedro Brito Guilherme Rocha Lino de Souza Kátia Flávia Fernandes 《Biotechnology progress》2021,37(5):e3182
Aedes aegypti is a mosquito vector of arboviruses such as dengue, chikungunya, zika and yellow fever that cause important public health diseases. The incidence and gravity of these diseases justifies the search for effective measures to reduce the presence of this vector in the environment. Bioinsecticides are an effective alternative method for insect control, with added ecological benefits such as biodegradability. The current study demonstrates that a chitinolytic enzyme complex produced by the fungus Trichoderma asperellum can disrupt cuticle formation in the L3 larvae phase of A. aegypti, suggesting such biolarvicidal action could be used for mosquito control. T. asperellum was exposed to chitin from different sources. This induction of cell wall degrading enzymes, including chitinase, N-acetylglucosaminidase and β-1,3-glucanase. Groups of 20 L3 larvae of A. aegypti were exposed to varying concentrations of chitinolytic enzymes induced with commercial chitin (CWDE) and larvae cell wall degrading enzymes (L-CWDE). After 72 h of exposure to the CWDE, 100% of larvae were killed. The same percent mortality was observed after 48 h of exposure to L-CWDE at half the CWDE enzyme mixture concentration. Exoskeleton deterioration was further observed by scanning and electron microscopy. Our findings indicate that L-CWDE produced by T. asperellum reflect chitinolytic enzymes with greater specificity for L3 larval biomolecules. This specificity is characterized by the high percentage of mortality compared with CWDE treatments and also by abrupt changes in patterns of the cellular structures visualized by scanning and transmission electron microscopy. These mixtures of chitinolytic enzymes could be candidates, as adjuvant or synergistic molecules, to replace conventional chemical insecticides currently in use. 相似文献
896.
Seminal coagulation and sperm quality in different social contexts in captive tufted capuchin monkeys (Sapajus apella) 下载免费PDF全文
897.
Andrade Edilene Pereira de Araújo Nunes Ana Bárbara de Freitas Alves Kilvia Ugaya Cássia Maria Lie da Costa Alencar Mateus de Lima Santos Tayane da Silva Barros Viviane Pastor Amandine Valérie de Figueirêdo Maria Cléa Brito 《The International Journal of Life Cycle Assessment》2020,25(12):2342-2358
The International Journal of Life Cycle Assessment - This paper presents the regionalized water scarcity characterization factors (CFs) of the available water remaining (AWARE) model, which was... 相似文献
898.
899.
Anabela Bensimon‐Brito Maria Leonor Cancela Ann Huysseune Paul Eckhard Witten 《Evolution & development》2012,14(1):116-127
The vertebral column results from a controlled segmentation process associated with two main structures, the notochord and the somites. Pathological fusion of vertebral bodies can result from impaired segmentation during embryonic development or occur postnatally. Here, we explore the process of formation and subsequent fusion of the caudalmost vertebral bodies in zebrafish, where fusion is a normal process, mechanically required to support the caudal fin. To reveal whether the product of fusion is on an evolutionary or a developmental scale, we analyze the mode of formation of vertebral bodies, identify transitory rudiments, and characterize vestiges that indicate previous fusion events. Based on a series of closely spaced ontogenetic stages of cleared and stained zebrafish, parasagittal sections, and detection methods for elastin and mineral, we conclude that the formation of the urostyle involves four fusion events. Although fusion of preural 1 (PU1+) with ural 1 (U1) and fusion within ural 2 (U2+) are no longer traceable during centrum formation (phylogenetic fusion), fusion between the compound centrum [PU1++U1] and U2+ (ontogenetic fusion) occurs after individualization of the centra. This slow process is the last fusion and perhaps the latest fusion during the evolution of the zebrafish caudal fin endoskeleton. Newly described characters, such as a mineralized subdivision within U2+, together with the reinterpretation of known features in an evolutionary–developmental context, strongly suggest that the zebrafish caudal fin endoskeleton is made from more fused vertebral bodies than previously assumed. In addition, these fusion events occur at different developmental levels depending on their evolutionary status, allowing the dissection of fusion processes that have taken place over different evolutionary times. 相似文献
900.