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51.
Braga DP Setti A Figueira Rde C Iaconelli A Borges E 《Gynecological endocrinology : the official journal of the International Society of Gynecological Endocrinology》2012,28(7):549-552
The objective of this study was to evaluate whether seasonality affects human-assisted reproduction treatment outcomes. For this, 1932 patients undergoing intracytoplasmic sperm injection (ICSI) were assigned to a season group according to the day of oocyte retrieval: winter (n = 435), spring (n = 444), summer (n = 469) or autumn (n = 584). Analysis of variance was used to compare the ICSI outcomes. The fertilization rate was increased during the spring (winter: 67.9%, spring: 73.5%, summer: 68.7% and autumn: 69.0%; p < 0.01). In fact, a nearly 50% increase in the fertilization rate during the spring was observed (odds ratio 1.45, confidence interval 1.20-1.75; p < 0.01). The oestradiol concentration per number of oocytes was significantly higher during the spring (winter: 235.8 pg/mL, spring: 282.1 pg/mL, summer: 226.1 pg/mL and autumn: 228.7 pg/mL; p = 0.030). This study demonstrates a seasonal variability in fertilization after ICSI, where fertilization is higher during the spring than at any other time. 相似文献
52.
Elena Migulez Jos María Zumalacrregui Maria Teresa Osorio Ana Cristina Figueira Beatriz Fonseca Javier Mateo 《Small Ruminant Research》2008,77(1):65-70
The quality of suckling-lamb meat (derived from Churra, Castellana and Ojalada breeds), covered by the protected geographical indication (PGI) “Lechazo de Castilla y León”, and the effects of carcass weight (CW), breed and sex on quality were studied. The edible portion (EP) of 81 carcasses was analysed for proximate composition, fatty acid, cholesterol, amino acid and mineral contents. The longissimus thoracis and lumborum muscle (30 samples) were analysed for proximate composition, pH, myoglobin content, water holding capacity, Warner–Bratzler shear force, and total and soluble collagen content. This study contributes to characterization of suckling-lamb meat quality recognised in the European Union with a PGI label and provides new data on the composition of the EP of the carcasses. CW and breed had a significant effect on several quality traits, most related to fatness. 相似文献
53.
Lucas Bleicher Ricardo Aparicio Fabio M Nunes Leandro Martinez Sandra M Gomes Dias Carolina Migliorini Ana Figueira Auxiliadora Morim Maria Santos Walter H Venturelli Rosangela da Silva Paulo Marcos Donate Francisco AR Neves Luiz A Simeoni John D Baxter Paul Webb Munir S Skaf Igor Polikarpov 《BMC structural biology》2008,8(1):1-13
Background
Multiple protein templates are commonly used in manual protein structure prediction. However, few automated algorithms of selecting and combining multiple templates are available.Results
Here we develop an effective multi-template combination algorithm for protein comparative modeling. The algorithm selects templates according to the similarity significance of the alignments between template and target proteins. It combines the whole template-target alignments whose similarity significance score is close to that of the top template-target alignment within a threshold, whereas it only takes alignment fragments from a less similar template-target alignment that align with a sizable uncovered region of the target. We compare the algorithm with the traditional method of using a single top template on the 45 comparative modeling targets (i.e. easy template-based modeling targets) used in the seventh edition of Critical Assessment of Techniques for Protein Structure Prediction (CASP7). The multi-template combination algorithm improves the GDT-TS scores of predicted models by 6.8% on average. The statistical analysis shows that the improvement is significant (p-value < 10-4). Compared with the ideal approach that always uses the best template, the multi-template approach yields only slightly better performance. During the CASP7 experiment, the preliminary implementation of the multi-template combination algorithm (FOLDpro) was ranked second among 67 servers in the category of high-accuracy structure prediction in terms of GDT-TS measure.Conclusion
We have developed a novel multi-template algorithm to improve protein comparative modeling. 相似文献54.
Andra L. T. De Souza Marcel O. Tanaka G. Wilson Fernandes Jos E. C. Figueira 《Austral ecology》2001,26(2):173-178
The response of a host plant to gall‐inducing insects varies both among and within plants, so that different levels of resources are available to the insects. The weevil Collabismus clitellae Boheman induces galls on the shoots of Solanum lycocarpum St Hil. in south‐east Brazil. Galls are found on a range of parts within an individual plant and are more abundant on smaller plants. In the present study, the host plant response as a possible influence on the performance of C. clitellae both between and within plants was tested. Gall abortion increased with plant height. Within plants, gall size was positively related to shoot diameter and number of chambers within the gall. The increase in gall larval density (number of individuals per gall volume unit) resulted in smaller adults and reduced developmental rates, probably because of resource limitation within the gall. The number of eggs laid by females increased with shoot diameter. Females laid more eggs on thicker shoots, where there are fewer chances to form galls with high larval density. However, this relationship was weak and a large variation was found for adult sizes. The availability of high quality sites is limited to smaller plants and thicker shoots located on the basal region of the plant. The phenotypic plasticity of this insect species in adult size and development time allows individuals growing on low quality sites to reach maturity, thus enhancing exploitation of the host plant. 相似文献
55.
Euan J. Provost Brendan P. Kelaher Symon A. Dworjanyn Bayden D. Russell Sean D. Connell Giulia Ghedini Bronwyn M. Gillanders WillIAM Figueira Melinda A. Coleman 《Global Change Biology》2017,23(1):353-361
The combination of ocean warming and acidification brings an uncertain future to kelp forests that occupy the warmest parts of their range. These forests are not only subject to the direct negative effects of ocean climate change, but also to a combination of unknown indirect effects associated with changing ecological landscapes. Here, we used mesocosm experiments to test the direct effects of ocean warming and acidification on kelp biomass and photosynthetic health, as well as climate‐driven disparities in indirect effects involving key consumers (urchins and rock lobsters) and competitors (algal turf). Elevated water temperature directly reduced kelp biomass, while their turf‐forming competitors expanded in response to ocean acidification and declining kelp canopy. Elevated temperatures also increased growth of urchins and, concurrently, the rate at which they thinned kelp canopy. Rock lobsters, which are renowned for keeping urchin populations in check, indirectly intensified negative pressures on kelp by reducing their consumption of urchins in response to elevated temperature. Overall, these results suggest that kelp forests situated towards the low‐latitude margins of their distribution will need to adapt to ocean warming in order to persist in the future. What is less certain is how such adaptation in kelps can occur in the face of intensifying consumptive (via ocean warming) and competitive (via ocean acidification) pressures that affect key ecological interactions associated with their persistence. If such indirect effects counter adaptation to changing climate, they may erode the stability of kelp forests and increase the probability of regime shifts from complex habitat‐forming species to more simple habitats dominated by algal turfs. 相似文献
56.
L da Silva Lopes RB Marques HB Fernandes S da Silva Pereira MC Ayres MH Chaves FR Almeida 《Journal of biomedical science》2012,19(1):68-6
ABSTRACT: BACKGROUND: The mechanisms of the antinociceptive activity of () epicatechin (EPI), a compound isolated from the hydroalcoholic fraction of Combreum leprosum Mart & Eicher. METHODS: were assessed in the model of chemical nociception induced by glutamate (20 mumol/paw). To evaluate the mechanisms involved, the animals , male Swiss mice (25-30 g), received EPI (50 mg/kg p.o.) after pretreatment with naloxone (2 mg/kg s.c. opioid antagonist), glibenclamide (2 mg/kg s.c. antagonist K + channels sensitive to ATP), ketanserin (0.3 mg/kg s.c. antagonist of receptor 5-HT2A), yoimbine (0.15 mg/kg s.c. alpha2 adrenergic receptor antagonist), pindolol (1 mg/kg s.c. 5-HT1a/1b receptor antagonist), atropine (0.1 mg/kg s.c. muscarinic antagonist) and caffeine (3 mg/kg s.c. adenosine receptor antagonist), ondansetron (0.5 mg/kg s.c. for 5-HT3 receptor) and L-arginine (600 mg/kg i.p.). RESULTS: The antinociceptive effect of EPI was reversed by pretreatment with naloxone and glibenclamide, ketanserin, yoimbine, atropine and pindolol, which demonstrates the involvement of opioid receptors and potassium channels sensitive to ATP, the serotoninergic (receptor 5HT1A and 5HT2A), adrenergic (receptor alpha 2) and cholinergic (muscarinic receptor) systems in the activities that were observed. The effects of EPI, however, were not reversed by pretreatment with caffeine, L-arginine or ondansetron, which shows that there is no involvement of 5HT3 receptors or the purinergic and nitrergic systems in the antinociceptive effect of EPI. In the Open Field and Rotarod test, EPI had no significant effect, which shows that there was no central nervous system depressant or muscle relaxant effect on the results. CONCLUSIONS: This study demonstrates that the antinociceptive activity of EPI in the glutamate model involves the participation of the opioid system, serotonin, adrenergic and cholinergic. 相似文献
57.
Thaís Queiroz Morcatty Hani Rocha El Bizri Hellem Cristina Silva Carneiro Rodrigo Ludolf Biasizzo Cândida Radicchi de Oliveira Alméri Ericson Sousa da Silva Flávio Henrique Guimarães Rodrigues José Eugênio Côrtes Figueira 《Ecological Research》2013,28(6):935-947
Habitat loss is considered to be the principal cause of the local extinction of mammals worldwide. We assessed the extinction pattern of medium- and large-sized mammals caused by the effects of habitat loss in reserves in the Quadrilátero Ferrífero, southeastern Brazil, and discussed the effectiveness of these natural remnants for conserving mammals. A literature review and field collections were conducted from 2006 to 2011 to estimate the composition and richness of mammals in nine remnants of different sizes, including reserves and non-protected areas. A species–area relation and a nested subset analysis were performed, and a degree of sensitivity to habitat loss was obtained for each species according to its frequency of occurrence. Forty-five species of mammals were recorded. There was a strong species–area relation involving the legal size of reserves. High species richness was associated with large reserves, and the z value was within the range of very isolated continental remnants. The mammalian community exhibited a nested occurrence pattern, suggesting that most species were part of a more continuous ecosystem and that non-random extinction caused by habitat loss occurred in southeastern Brazil. The negative relation found between species frequencies and body weights suggested that selective species loss is associated with decreases in the size of the reserves. The estimated viable size required to conserve all of the sensitive species is greater than the size of the largest reserve inventoried. We recommend the aggregation of neighboring natural remnants and the creation of new reserves to reduce extinction risks. 相似文献
58.
Endogenous chloride channels of insect sf9 cells. Evidence for coordinated activity of small elementary channel units 总被引:1,自引:0,他引:1
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EH Larsen SE Gabriei MJ Stutts J Fullton EM Price RC Boucher 《The Journal of general physiology》1996,107(6):695-714
The endogenous Cl- conductance of Spodoptera frugiperda (Sf9) cells was studied 20-35 h after plating out of either uninfected cells or cells infected by a baculovirus vector carrying the cloned beta-galactosidase gene (beta-Gal cells). With the cation Tris+ in the pipette and Na+ in the bath, the reversal potential of whole-cell currents was governed by the prevailing Cl- equilibrium potential and could be fitted by the Goldman-Hodgkin-Katz equation with similar permeabilities for uninfected and beta-Gal cells. In the frequency range 0.12 < f < 300 Hz, the power density spectrum of whole-cell Cl- currents could be fitted by three Lorentzians. Independent of membrane potential, >50% of the total variance of whole-cell current fluctuations was accounted for by the low frequency Lorentzian (fc = 0.40 +/- 0.03 Hz, n = 6). Single-Cl- channels showed complex gating kinetics with long lasting (seconds) openings interrupted by similar long closures. In the open state, channels exhibited fast burst-like closures. Since the patches normally contained more than a single channel, it was not possible to measure open and closed dwell-time distributions for comparing single-Cl- channel activity with the kinetic features of whole-cell currents. However, the power density spectrum of Cl- currents of cell-attached and excised outside-out patches contained both high and low frequency Lorentzian components, with the corner frequency of the slow component (fc = 0.40 +/- 0.02 Hz, n = 4) similar to that of whole-cell current fluctuations. Chloride channels exhibited multiple conductance states with similar Goldman-Hodgkin-Katz-type rectification. Single-channel permeabilities covered the range from approximately 0.6.10(-14) cm5/s to approximately 6.10(-14) cm3/s, corresponding to a limiting conductance (gamma 150/150) of approximately 3.5 pS and approximately 35 pS, respectively. All states reversed near the same membrane potential, and they exhibited similar halide ion selectivity, P1 > PCl approximately PBr. Accordingly, Cl- current amplitudes larger than current flow through the smallest channel unit resolved seem to result from simultaneous open/shut events of two or more channel units. 相似文献
59.
H?Bukulmez AL?Matthews CM?Sullivan C?Chen MJ?Kraay RC?Elston RW?Moskowitz VM?Goldberg ML?WarmanEmail author 《Arthritis research & therapy》2005,8(1):R25
In order to determine whether there is a genetic component to hip or knee joint failure due to idiopathic osteoarthritis (OA),
we invited patients (probands) undergoing hip or knee arthroplasty for management of idiopathic OA to provide detailed family
histories regarding the prevalence of idiopathic OA requiring joint replacement in their siblings. We also invited their spouses
to provide detailed family histories about their siblings to serve as a control group. In the probands, we confirmed the diagnosis
of idiopathic OA using American College of Rheumatology criteria. The cohorts included the siblings of 635 probands undergoing
total hip replacement, the siblings of 486 probands undergoing total knee replacement, and the siblings of 787 spouses. We
compared the prevalence of arthroplasty for idiopathic OA among the siblings of the probands with that among the siblings
of the spouses, and we used logistic regression to identify independent risk factors for hip and knee arthroplasty in the
siblings. Familial aggregation for hip arthroplasty, but not for knee arthroplasty, was observed after controlling for age
and sex, suggesting a genetic contribution to end-stage hip OA but not to end-stage knee OA. We conclude that attempts to
identify genes that predispose to idiopathic OA resulting in joint failure are more likely to be successful in patients with
hip OA than in those with knee OA. 相似文献
60.
Ono EY Fungaro MH Sofia SH Figueira EL Gerage AC Ichinoe M Sugiura Y Ueno Y Hirooka EY 《Mycopathologia》2004,158(4):451-455
Eleven feed samples associated with six animal (horse and poultry) intoxication outbreaks (1991) in the state of Paraná, Brazil,
were evaluated for fungal and fumonisin contamination. In order to estimate the␣trend of livestock intoxication, fumonisin
contamination was monitored in corn produced both at the commercial level (1991, 1995 crop), and in an experimental field
at a local Agronomy Institute (1997 crop). The total mould count in the feed samples ranged from 2.9 × 103 to 1.9 × 107 CFU/g, with Fusarium verticillioides as the predominant species, at a high count of 2.4 × 104–6.5 × 105 CFU/g. Fumonisins (FB1 + FB2) were detected in all corn-based feed samples at levels ranging from 2.89 to 14.54 μg/g. All 27 Northern corn samples (1991 crop) were contaminated with fumonisins at levels ranging from 2.32 to 16.64 μg/g. Twenty-six (96.3%) out of 27 corn samples from the Central-Southern region (1995 crop) were positive for fumonisins (FB1+FB2), with the range of 0.07–3.66 μg/g, while all 37 Northern samples (1995 crop) were contaminated with fumonisins ranging from 0.57 to 9.97 μg/g. Twenty-one out of 37 corn samples from the Northern region (1997 crop) were positive for fumonisins, but at low level
(range of 0.05–2.67 μg/g). The results showed a decreasing trend in fumonisin contamination over the years. Nowadays animal intoxication outbreaks
rarely occur in this State, as both animal producers and feed industries have become conscious about monitoring of corn and
other raw materials at the quality control level. 相似文献