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The EMBO–FEBS lecture course on the ‘Molecular Basis of Bacterial Virulence and Survival Within Infected Hosts and in the Environment’, organized by Pascale Cossart, Efstathios Gonos and Roberto Kolter, was held on the island of Spetsai, Greece, September 3–13, 2002. 相似文献
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Piquemal D Commes T Manchon L Lejeune M Ferraz C Pugnère D Demaille J Elalouf JM Marti J 《Genomics》2002,80(3):361-371
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Differential channelling of liver lipids in relation to susceptibility to hepatic steatosis in two species of ducks 总被引:1,自引:0,他引:1
Hermier D Guy G Guillaumin S Davail S André JM Hoo-Paris R 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2003,135(4):663-675
In the human, hepatic steatosis can be associated with an imbalance between synthesis, secretion and storage of hepatic lipids, and exhibits a genetic susceptibility. The effect of overfeeding on hepatic lipid channelling was investigated in two genotypes of ducks that differ in their susceptibility to fatty liver, i.e. the common duck, Anas platyrhynchos, and the Muscovy duck, Cairina moschata. Before overfeeeding, the Muscovy duck exhibited a lower subcutaneous adiposity and a higher muscular development, whereas hepatic composition was similar in both genotypes (>5% lipids and triglycerides accounting for 6–10% lipids). In the plasma lipoprotein profile, HDL predominated (5.5–7.8 g/l) over VLDL (0.09–0.25 g/l) and LDL (0.65–1.06 g/l). All lipid and lipoprotein concentrations were lower in the Muscovy duck. In response to overfeeding, the Muscovy duck exhibited a higher degree of hepatic steatosis (62 vs. 50% lipids), and a lower increase in adiposity and in the concentration of plasma triglycerides (6-fold vs. 10-fold) and VLDL (23-fold vs. 34-fold). Thus, certain genotypes may be more responsive to the dietary induction of fatty liver because of a less efficient channelling of hepatic lipids towards secretion into plasma and adipose storage, and the duck may represent a suitable model in which to study the development of hepatic steatosis and its pathogenesis. 相似文献
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Material and methods
The study population consisted of 39 subjects divided into two groups: 21 azoospermic males and 18 oligoazoospermic males. These men were selected in andrology departments over a period of six months. The andrology and liaison psychiatry departments of Lille university hospital established a general infertility questionnaire. This semi-structured questionnaire comprising 40 questions was based on clinical experience and describes the clinical and symptomatic context of infertility. An individual 50-item questionnaire was then used to analyse the psychosocial, marital and sexual effects of male infertility and the representation of the psychiatrist in the andrology department.Results
One third of patients discovered the diagnosis of infertility when the biologist gave them the results of the semen analysis. Our patients initially envisaged marital, psychological and social problems, but very few sexual problems. They imagined that infertility was more disturbing for women than for men, from a psychological and sexual point of view. 82% of our subjects imagined that their partner had no sexual problems. 48.7% of them thought that their partner had no psychological difficulties related to their infertility. The oligoasthenospermia group considered that the partner had significantly more “psychological difficulties” compared to the azoospermia group. 41% of our patients felt guilty towards their partner because of their infertility diagnosis. 10.3% of patients presented sexual disorders before the diagnosis of male infertility and 25.6% presented sexual disorders after this diagnosis. Contrary to data in the literature, a major change of sexuality was not observed in the majority of the couples after the diagnosis. When sexuality changed, it generally consisted of a reduction of the frequency of sexual relations. Among the patients who reported sexual difficulties, only 40% related them to infertility. 50% did not report any relationship between the psychological difficulties related to infertility and the sexual difficulties. Contrary to the data in the literature, neither the loss of spontaneity during sexual relations, nor the complementary investigations necessary for artificial insemination had any influence on sexuality. 89.8% of our patients are ready to change their sexual practices in order to be more fertile without causing any sexual or psychological problems. However, only 34.3% of patients reported a concern about reproductive efficacy during sexual relations. A more marked sexuality/reproduction dissociation was observed in oligoazoospermic males than in azoospermic males. 28.2% of patients reported that talking about their sexual and/or psychological problems with a psychiatrist was helpful.Conclusion
Many contradictions and underestimations were observed in the answers to the questions. We confirmed the existence of a psychological and sexual distress, but which was quantitatively less severe than that described in “gynaecological” populations. However, a real psychological and sexual distress does exist in our population, which is why we propose from the outset a psychosomatic and sexological treatment of infertility in order to prevent the onset of these sexual difficulties. Our questionnaire was based on clinical experience and helped our patients to identify their psychological and sexual difficulties related to infertility and its treatment. It would therefore be useful for the practitioner, andrologist or psychiatrist, to help the patient express the effects related to this “new medicalized sexuality”. 相似文献109.
The symbiotic hydrothermal vent tubeworm Riftia pachyptila needs to supply its internal bacterial symbionts with carbon dioxide, their inorganic carbon source. Our aim in this study was to characterize the carbonic anhydrase (CA) involved in CO(2) transport and conversion at various steps in the plume and the symbiotic tissue, the trophosome. A complete 1209 kb cDNA has been sequenced from the trophosome and identified as a putative alpha-CA based on BLAST analysis and the similarities of total deduced amino-acid sequence with those from the GenBank database. In the plume, the putative CA sequence obtained from cDNA library screening was 90% identical to the trophosome CA, except in the first 77 nucleotides downstream from the initiation site identified on trophosome CA. A phylogenetic analysis showed that the annelidan Riftia CA (CARp) emerges clustered with invertebrate CAs, the arthropodan Drosophila CA and the cnidarian Anthopleura CA. This invertebrate cluster appeared as a sister group of the cluster comprising mitochondrial and cytosolic isoforms in vertebrates: CAV, CAI II and III, and CAVII. However, amino acid sequence alignment showed that Riftia CA was closer to cytosolic CA than to mitochondrial CA. Combined biochemical approaches revealed two cytosolic CAs with different molecular weights and pI's in the plume and the trophosome, and the occurrence of a membrane-bound CA isoform in addition to the cytosolic one in the trophosome. The physiologic roles of cytosolic CA in both tissues and supplementary membrane-bound CA isoform in the trophosome in the optimization of CO(2) transport and conversion are discussed. 相似文献
110.
Cianciarullo AM Bertho AL Soares MJ Hosoda TM Nogueira-Silva S Beçak W 《Cell biology international》2003,27(9):747-753
Properly metabolized globin synthesis and iron uptake are indispensable for erythroid cell differentiation and maturation. Mitochondrial participation is crucial in the process of haeme synthesis for cytochromes and haemoglobin. We studied the final biosynthesis site of haemoglobin using an ultrastructural approach, with erythroid cells obtained from rabbit embryos, in order to compare these results with those of animals treated with saponine or phenylhydrazine. Our results are similar to those obtained in assays with adult mammals, birds, amphibians, reptiles and fish, after induction of haemolytic anaemia. Therefore, the treatment did not interfere with the process studied, confirming our previous findings. Immunoelectron microscopy showed no labelling of mitochondria or other cellular organelles supposedly involved in the final biosynthesis of haemoglobin molecules, suggesting instead that it occurs free in the cytoplasm immediately after the liberation of haeme from the mitochondria, by electrostatic attraction between haeme and globin chains. 相似文献