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161.
Juliana Costa Jord?o Ana Cristina Vigliar Bondioli Flavia Maria Guebert Benoit de Thoisy Lurdes Foresti de Almeida Toledo 《Genetics and molecular biology》2015,38(3):346-352
Sea turtles are marine reptiles that undertake long migrations through their life, with limited information regarding juvenile stages. Feeding grounds (FGs), where they spend most of their lives, are composed by individuals from different natal origins, known as mixed stock populations. The aim of this study was to assess genetic composition, natal origins and demographic history of juvenile green turtles (Chelonia mydas) at the Paranaguá Estuarine Complex (PEC), Brazil, considered a Natural World Heritage site. Tissue samples of stranded animals were collected (n = 60), and 700 bp mitochondrial DNA sequences were generated and compared to shorter sequences from previously published studies. Global exact tests of differentiation revealed significant differences among PEC and the other FGs, except those at the South Atlantic Ocean. Green turtles at PEC present genetic signatures similar to those of nesting females from Ascension Island, Guinea Bissau and Aves Island/Surinam. Population expansion was evidenced to have occurred 20–25 kYA, reinforcing the hypothesis of recovery from Southern Atlantic refugia after the last Glacial Maximum. These results contribute to a better understanding of the dynamics of green turtle populations at a protected area by providing knowledge on the dispersion patterns and reinforcing the importance of the interconnectivity between nesting and foraging populations. 相似文献
162.
Dayvison Francis Saraiva Freitas Iluska Augusta Rocha Lima Carolina Lemos Curi Livia Jord?o Rosely Maria Zancopé-Oliveira Antonio Carlos Francesconi do Valle Maria Clara Gutierrez Galhardo Andre Luiz Land Curi 《Memórias do Instituto Oswaldo Cruz》2014,109(2):262-264
Sporotrichosis associated with exposure to domestic cats is hyperendemic in Rio de
Janeiro, Brazil. A review of the clinical records at our institute revealed four
patients with clinical signs of dacryocystitis and a positive conjunctival culture
for Sporothrix who were diagnosed with Sporothrix
dacryocystitis. Three patients were children (< 13 years of age) and one patient
was an adult. Two patients reported contact with a cat that had sporotrichosis.
Dacryocystitis was associated with nodular, ulcerated lesions on the face of one
patient and with granulomatous conjunctivitis in two patients; however, this
condition manifested as an isolated disease in another patient. All of the patients
were cured of the fungal infections, but three patients had chronic dacryocystitis
and one patient developed a cutaneous fistula. Sporotrichosis is usually a benign
disease, but may cause severe complications when the eye and the adnexa are affected.
Physicians, especially ophthalmologists in endemic areas, should be aware of the
ophthalmological manifestations and complications of sporotrichosis. 相似文献
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Summary Cell cycle parameters were studied inCaesalpinia peltophoroides meristems proliferating under different oxygen tensions. This species has been selected for mixed planting in degraded areas
in Brazil, some of which are occasionally flooded. As the species’ adaptation to oxygen deprivation during flooding is not
fully understood, the objective of this study was to characterize the meristematic activity of root cells under various oxygen
regimes. Synchronous binucleate cells, induced by a pulse of caffeine, showed a cell-cycle time constant under both control
(5.6 mg of O2 per l) and oxygenated conditions (7.9 and 3.2 mg of O2 per l). The whole cell cycle lasted 10 h, although the relative duration of metaphase and anaphase/early telophase increased
in more hypoxic conditions. The species appeared to utilise oxygen diffusing from the shoot to the root system to maintain
cell division and root growth. 相似文献
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Long-term exposure to high doses of caffeine affects several aspects of nitrogen metabolism, such as purine, pyrimidine and urea synthesis. However, little is known about the mechanisms of these changes and if they occur at shorter term. We have studied in isolated hepatocytes: 1) the in vitro effect of high doses of caffeine on amino acid levels, 2) the main destination of ammonia and carbon chains from amino acid catabolism, and 3) the cytosolic and mitochondrial redox states. We have found that, whereas it has a small effect on urea synthesis and on the levels of the cofactors and intermediates, it decreases the levels of several amino acids, the gluconeogenesis and the redox state. Our results suggest that a longer exposure to caffeine is necessary to affect the normal functions of some metabolic pathways. 相似文献
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A. Valdivia S. Pérez-Álvarez J. D. Aroca-Aguilar I. Ikuta J. Jordán 《Journal of physiology and biochemistry》2009,65(2):195-208
Reactive oxygen species (ROS) are known participants in several cellular processes. Superoxide anion radical, one example of ROS, forms as a result of normal cellular respiration and is usually cleared successfully by superoxide dismutase (SOD) and other radical scavengers. However, when superoxide exceeds the clearance capacity of SOD and other ROS scavengers, superoxide initiates a number of pathologic processes. This review examines pathologies involving superoxide, including: cancer, neurodegenerative diseases, ischemia/reperfusion injury, and inflammation. We will also explore the basic science principles of superoxide and SOD, including: SOD evolution, SOD mutations, biochemistry, physiology, and pathophysiology. In reviewing the basic science, clinical pathology, and therapeutic research, we hope to clearly demonstrate plausible pharmacologic targets of action. We have revised data about basic science, clinical pathology and therapeutic research in an effort to propose plausible pharmacological targets of action. The understanding of these aspects is critical in the accomplishment of a successful clinical intervention. 相似文献