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61.
The widely used antidepressants Specific Serotonin Reuptake Inhibitors (SSRI) have been tried with success as anticonvulsants in cases of nonsymptomatic epilepsy. This attempt was performed on the basis of experimental data suggesting the involvement of impairments of the serotonin system in the genesis of epilepsy. This overview summarizes the clinical data and presents biochemical and neurochemical evidences suggesting the mechanism of the therapeutic effects of SSRI in nonsymptomatic epilepsy. In particular, studies on blood-borne neutral amino acids and platelet serotonin transporter (SERT) in epileptics suggest: (a) That a decreased brain availability of tryptophan may be related to some types of epilepsy. (b) That reduction of the density of SERT may be a homeostatic reaction in the brain following epileptic seizures. 相似文献
62.
The binding of [3H]-paroxetine to membrane serotonin transporter (SERT) has been studied in membranes from different sources and subcellular
fractions. From rat were membranes from venous blood platelets, brain total cortex, brain microsomes, brain crude and purified
synaptosomes. Membranes were obtained from venous blood platelets from human volunteers and from brain cortex tissue from
neurosurgery (cerebral lobectomies following craniocerebral injuries). The main finding was that the K
D of paroxetine binding to the SERT was the same for platelet and nerve ending (synaptosomal) membranes. That parameter was
significantly lower in membranes from brain microsomes and cortex total tissue. No species related difference was found, where
comparison was possible, between human and rat tissue. The equality of K
D of paroxetine binding to blood platelet membranes and to membranes from nerve endings appears to encourage the use of such
membranes as a model for brain SERT. Binding at two different temperatures for several of the fractions suggests that paroxetine–SERT
interaction is entropy-driven. 相似文献
63.
Francisco Santiago-Quesada Jos A. Masero Noelia Albano Auxiliadora Villegas Juan M. Snchez-Guzmn 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2009,152(4):565-568
Digestive assimilation efficiency is considered a trait with important implications for animal ecology. However, practically all studies have ignored the importance of sex differences in food assimilation efficiency (AE). Here, we investigated sex differences in dietary and physiological parameters in the Black-tailed Godwit Limosa limosa limosa feeding on rice seeds, a species with sexual dimorphism in body size and body mass. Gross daily food intake, gross energy intake, gross energy output and metabolizable energy intake did not vary significantly between sexes, but godwit females showed lower faeces energy density and higher AE than males. Mass-specific AE was similar in males and females, and the difference in AE could be attributed to the females' greater body mass. We suggest that a differential AE could play a role in explaining sex differences in habitat or micro-habitat selection during the non-breeding season in bird species with sexual dimorphism in size. Finally, we addressed the question about assimilation efficiency accuracy in models that estimate prey acquisitions by declining shorebirds as the Black-tailed Godwit. 相似文献
64.
Monica M. Lins-de-Barros Ricardo P. Vieira Alexander M. Cardoso Vivian A. Monteiro Aline S. Turque Cynthia B. Silveira Rodolpho M. Albano Maysa M. Clementino Orlando B. Martins 《Microbial ecology》2010,59(3):523-532
Reef-building corals may be seen as holobiont organisms, presenting diverse associated microbial communities. Best known is
the symbiotic relationship with zooxanthellae, but Archaea, Bacteria, fungi, viruses, and algal plastids are also abundant.
Until now, there is little information concerning microbial communities associated with Brazilian corals. The present study
aims to describe the diversity of Archaea, Bacteria, and eukaryotic algal plastid communities associated with two sympatric
species, Siderastrea stellata and Mussismilia hispida, from Southeastern Brazil, using 16S rRNA gene libraries. Since corals present a high number of other associated invertebrates,
coral barcoding (COI) was performed to confirm the exclusive occurrence of coral DNA in our samples. Our analysis yielded
354 distinct microbial OTUs, represented mainly by novel phylotypes. Richness (Chao1 and ACE) and diversity (H') estimations
of the microbial communities associated with both species were high and comparable to other studies. Rarefaction analyses
showed that microbial diversity of S. stellata is higher than that of M. hispida. Libshuff comparative analyses showed that the highest microbial community similarity between the two coral species occurred
in the bacterial libraries, while archaeal and plastidial communities were significantly different. Crenarchaeota dominated
archaeal communities, while Proteobacteria was the most abundant bacterial phylum, dominated by alpha-Proteobacteria. Plastids
were also represented by novel phylotypes and did not match with any 16S rRNA sequences of Cyanobacteria and zooxanthellae
from GenBank. Our data improves the pool of available information on Brazilian coral microbes and shows corals as sources
of diverse prokaryotic and picoeukaryotic communities. 相似文献
65.
Bertola DR Pereira AC Albano LM De Oliveira PS Kim CA Krieger JE 《Genetic testing》2006,10(3):186-191
Mutations in the PTPN11 gene are known to cause a large fraction of the cases of Noonan syndrome. The objective of this study was to determine the PTPN11 gene mutation rate in a cohort of clinically well-characterized Brazilian patients with Noonan or Noonan-like syndromes and to study the genotype-phenotype correlation. Fifty probands with Noonan syndrome ascertained according to well-established diagnostic criteria, 3 with LEOPARD syndrome, 5 with Noonan-like/multiple giant cell lesion syndrome, and 3 with neurofibromatosis/ Noonan were enrolled in this study. Mutational analysis was performed using denaturing high-performance liquid chromatography (DHPLC) followed by sequencing of amplicons with an aberrant elution profile. We detected missense mutations in the PTPN11 gene in 21 probands with Noonan syndrome (42%), in all 3 patients with LEOPARD syndrome, and in 1 case with Noonan-like/multiple giant cell lesion syndrome. One patient with neurofibromatosis-Noonan syndrome had a mutation in both the PTPN11 and NF1 genes. The only anomalies that reached statistical significance when comparing probands with and without mutations were the hematological abnormalities. Our data confirms that Noonan syndrome is a genetically heterogeneous disorder, with mutations in the PTPN11 gene responsible for roughly 50% of the cases. A definitive genotype-phenotype correlation has not been established, but the T73I mutation seems to predispose to a myeloproliferative disorder. Regarding Noonan-like syndromes, mutation of the PTPN11 gene is the main causal factor in LEOPARD syndrome, and it also plays a role in neurofibromatosis-Noonan syndrome. Noonan- like/multiple giant cell lesion syndrome, part of the spectrum of Noonan syndrome, is also heterogeneous. 相似文献
66.
Nogueira D Albano C Adriaenssens T Cortvrindt R Bourgain C Devroey P Smitz J 《Biology of reproduction》2003,69(3):1042-1052
This study addresses the role of cAMP hydrolytic isoenzyme phosphodiesterase type 3 (PDE 3) modulation on human oocyte maturation in vitro. Presence of phosphodiesterase type 3 A (PDE 3A) mRNA was confirmed in human germinal vesicle-stage (GV) oocytes. Making use of a selective PDE 3 inhibitor, Org 9935 (10 microM), oocytes retrieved from immature follicles were arrested in prophase I with a high efficiency for up to 72 h. Cumulus oocyte complexes (COCs) were retrieved in the follicular phase of the cycle before or after exposure to endogenous LH or hCG administration in vivo and randomly distributed into maturation medium with or without the PDE 3 inhibitor. Previous exposure of small follicles to LH activity in vivo had no influence on the arresting capacity of the PDE 3 inhibitor. Reversal from pharmacological arrest leads to a progression through meiosis in a normal time frame with formation of a well-aligned metaphase plate. Ultrastructure analysis of COC derived from follicles between 8 and 12 mm showed that the induced extension of prophase I arrest in vitro resulted in cytoplasm changes but not in apparent nuclear changes during culture. 相似文献
67.
Ubiquinone (coenzyme Q10), in addition to its function as an electron and proton carrier in mitochondrial electron transport coupled to ATP synthesis, acts in its reduced form (ubiquinol) as an antioxidant, inhibiting lipid peroxidation in biological membranes and protecting mitochondrial inner-membrane proteins and DNA against oxidative damage accompanying lipid peroxidation. Tissue ubiquinone levels are subject to regulation by physiological factors that are related to the oxidative activity of the organism: they increase under the influence of oxidative stress, e.g. physical exercise, cold adaptation, thyroid hormone treatment, and decrease during aging. In the present study, coenzyme Q homologues were separated and quantified in the brains of mice, rats, rabbits, and chickens using high-performance liquid chromatography. In addition, the coenzyme Q homologues were measured in cells such as NG-108, PC-12, rat fetal brain cells and human SHSY-5Y and monocytes. In general, Q1 content was the lowest among the coenzyme homologues quantified in the brain. Q9 was not detectable in the brains of chickens and rabbits, but was present in the brains of rats and mice. Q9 was also not detected in human cell lines SHSY-5Y and monocytes. Q10 was detected in the brains of mice, rats, rabbits, and chickens and in cell lines. Since both coenzyme Q and vitamin E are antioxidants, and coenzyme Q recycles vitamins E and C, vitamin E was also quantified in mice brain using HPLC-electrochemical detector (ECD). The quantity of vitamin E was lowest in the substantia nigra compared with the other brain regions. This finding is crucial in elucidating ubiquinone function in bioenergetics; in preventing free radical generation, lipid peroxidation, and apoptosis in the brain; and as a potential compound in treating various neurodegenerative disorders. 相似文献
68.
Bactericidal effect of chlorine on motile Aeromonas spp. in drinking water supplies and influence of temperature on disinfection efficacy 总被引:1,自引:0,他引:1
The susceptibility of toxigenic Aeromonas spp. to free chlorine in drinking water supplies, and the influence of environmental temperature on the bactericidal activity of the oxidant, were evaluated. The results showed inactivation curves characterized by an initial phase of rapid reduction of viable cells followed by a slow inactivation of bacteria. The effect of the chlorine compound was markedly influenced by water temperature. At a summer water temperature (20 °C), the efficacy of the chlorine concentrations tested was found to be two to three times lower compared to that found at a winter temperature (5 °C). Resistance was moderately, but significantly, greater in Aer. hydrophila vs Aer. caviae and Aer. sobria , but all Aeromonas spp. were more susceptible than Escherichia coli . Selective pressure with free chlorine did not produce Aeromonas cells with higher levels of chlorine resistance. 相似文献
69.
L Garnier J P Albano 《Comptes rendus des séances de la Société de biologie et de ses filiales》1977,171(5):1049-1053
Electrical stimulation of low threshold splanchnic afferent nerves in lightly anesthetized cat results in phrenic and recurrent laryngeal nerve responses. Both phrenic and recurrent laryngeal inspiratory nerve activities are inhibited, whereas expiratory recurrent nerve activity is triggered and even increased. The significance of this reflex is discussed in relation to laryngeal adductor muscle contractions and the abdominal pressure increase. 相似文献
70.
Effects of carbon tetrachloride on isolated rat hepatocytes. Inhibition of protein and lipoprotein secretion. 下载免费PDF全文
Both the protein components Kp1 and Kp2 of nitrogenase from Klebsiella pneumoniae were found to be stable in aq. 50% (v/v) ethylene glycol at +30 degrees C or below. At -20 degrees C in this medium their sensitivities to O2 were diminished somewhat. Though purification could be carried out at -20 degrees C, the product had the same specific activity and was obtained in the same yield as when the purification was carried out by standard procedures. This suggests that such procedures yield enzyme undamaged in the course of the purification by O2, thermal denaturation or proteolytic digestion. 相似文献