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41.
Caravello GU Tasso M Lucchetti E 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》2002,60(3):241-253
The surnames of populations of the municipalities with Cimbro and Mòcheno origins are compared with each other and with other municipalities of the neighbourhood. This study starts from the supposition that a community of surnames shares a common cultural origin, maintained by reciprocal mobility. The analysis has been carried out by using estimates of the similarities between populations, the topological representations obtained by them and the spatial autocorrelation. On the whole, this research shows no evidence of peculiar distinctions between the populations that share Cimbro and Mòcheno origins compared to the neighbouring ones. Moreover, there is not any evident process of undifferentiated diffusion along all the directions. On the contrary, it is emphasized that belonging to the same geographic region and to the same administrative subdivision mostly influences the similarity between populations. The exception is the Cimbro municipality of Luserna, which presents a peculiar structure of surnames different from other municipalities of the same territory. 相似文献
42.
Antonella Del Corso Pier Giuseppe Vilardo Mario Cappiello Ilaria Cecconi Massimo Dal Monte Daniela Barsacchi Umberto Mura 《Archives of biochemistry and biophysics》2002,397(2):392-398
Glutathione is one of the most relevant antioxidants present in cells. It exerts its scavenging action through the involvement of efficient and ubiquitous enzymes. GSH on the other hand, because of its chemical features, can scavenge reactive oxygen species without the involvement of enzymatic systems. The study deals with the mobilization of GSH pool in a nonenzymatic antioxidant system by other physiological thiols (i.e., cysteine and cysteinyl-glycine), which are far more sensitive than GSH to oxidative conditions. These thiol compounds, in the presence of iron/EDTA, can promote oxygen activation through their oxidation to disulfides. GSH, through trans-thiolation reactions, can regenerate Cys and CysGly, which can then recycle, thus inducing a massive GSH oxidation. In these conditions, making use of bovine lens aldose reductase as a protein model, evidence is given that Cys and CysGly promote specific protein S-thiolation reactions. The possibility that GSH may be recruited in controlling cellular oxygen tension is considered. 相似文献
43.
Oxidative stress in diabetes-induced endothelial dysfunction involvement of nitric oxide and protein kinase C 总被引:3,自引:0,他引:3
Pricci F Leto G Amadio L Iacobini C Cordone S Catalano S Zicari A Sorcini M Di Mario U Pugliese G 《Free radical biology & medicine》2003,35(6):683-694
Reactive oxygen species (ROS) formation plays a major role in diabetes-induced endothelial dysfunction, though the molecular mechanism(s) involved and the contribution of nitric oxide (NO) are still unclear. This study using bovine retinal endothelial cells was aimed at assessing (i) the role of oxygen-dependent vs. NO-dependent oxidative stress in the endothelial cell permeability alterations induced by the diabetic milieu and (ii) whether protein kinase C (PKC) activation ultimately mediates these changes. Superoxide, lipid peroxide, and PKC activity were higher under high glucose (HG) vs. normal glucose throughout the 30 d period. Nitrite/nitrate and endothelial NO synthase levels increased at 1 d and decreased thereafter. Changes in monolayer permeability to 125I-BSA induced by 1 or 30 d incubation in HG or exposure to advanced glycosylation endproduct were reduced by treatment with antioxidants or PKC inhibitors, whereas NO blockade prevented only the effect of 1 d HG. HG-induced changes were mimicked by a PKC activator, a superoxide generating system, an NO and superoxide donor, or peroxynitrite (attenuated by PKC inhibition), but not a NO donor. The short-term effect of HG depends on a combined oxidative and nitrosative stress with peroxynitrite formation, whereas the long-term effect is related to ROS generation; in both cases, PKC ultimately mediates permeability changes. 相似文献
44.
Cristina Sotgia Umberto Fascio Roberta Pennati Fiorenza De Bernardi 《Development, growth & differentiation》1998,40(1):75-84
Animal caps isolated from Xenopus laevis embryos at the blastula stage were treated sequentially with NH4 Cl, a known cement gland inducer, and with 12-O-tetradecanoyl phorbol-13-acetate (TPA), a known neural inducer. The two artificial inducers were also used in reverse order to see if they can mimic the natural inducers acting during the progressive determination of the ectodermal organ. Immunofluorescence and whole-mount in situ hybridization were used to study the expression of tubulin, taken to indicate an early step on the pathway of cell elongation, and neural cell adhesion molecule (N-CAM) taken to indicate an early step in the determination of the nervous system. The expression of XCG-1, a marker of early specification of the cement gland, was also studied. The results showed that the two artificial inducers can mimic the effects of the natural inducers in animal cap explants. The TPA behaves like a neural inducer, reducing the number and the extension of the cement gland when added to the medium in addition to NH4 Cl, before or after NH4 Cl treatment. In the process of cement gland/neural induction, it is possible to redirect the ectoderm already specified as cement gland to neural tissue, but it does not seem possible to respecify the neural tissue as cement gland. Moreover, the animal caps were also cut into dorsal and ventral parts and the two halves were treated separately. The results were similar to those obtained with treatment of the entire animal cap, suggesting that a dorsal-ventral pattern is not yet established before the gastrula stage, and that in normal embryos there are boundaries between the effects of different inducers. 相似文献
45.
Gian Carlo Manicardi Antonella Tombacco Davide Bizzaro Umberto Bianchi Patrizia Grace Bianchi Denny Sakkas 《The Histochemical journal》1998,30(1):33-39
The nick translation and terminal transferase assays have been compared to test their relative efficiency in detecting DNA breakage in ejaculated human spermatozoa. The results have been correlated with the percentage of chromomycin A3 positive sperm, a fluorochrome that is indicative of the protamination state of sperm. Examination of the ejaculated sperm of 30 subjects revealed that the percentage of positivity to the nick translation and terminal transferase assays did not differ, even when using different fixatives. It is concluded that the inability of the two assays to distinguish the type of DNA damage, as is possible in somatic nuclei, is most probably linked to the unique nature of sperm chromatin. It is proposed that the presence of the damaged DNA may be the remnants of an imperfect spermiogenesis, probably related to an inadequate protamine deposition. This is supported by the strong correlation between the presence of DNA damage and underprotamination as evidenced by chromomycin A3. © Chapman & Hall 相似文献
46.
Marco Salemi Anne-Mieke Vandamme Chiara Gradozzi Kristel Van Laethem Ercole Cattaneo Graham Taylor Claudio Casoli Patrick Goubau Jan Desmyter Umberto Bertazzoni 《Journal of molecular evolution》1998,46(5):602-611
Seven new Italian and two new British HTLV-II isolates were obtained from injecting drug users and the entire long terminal
repeat (LTR) region was sequenced. Restriction analysis showed that all the Italian isolates are of the IIb subtype, whereas
the British isolates are of the IIa subtype. To understand whether the further differentiation of each two principal HTLV-II
subtypes in several subgroups could be statistically supported by phylogenetic analysis, the neighbor-joining, parsimony,
and maximum likelihood methods were used. The separation between IIa and IIb is very well supported by all three methods.
At least two phylogenetic subgroups exist within the HTLV-IIa and at least three within the HTLV-IIb subtype. In the present
analysis, no statistical support was obtained for additional phylogroups. Two particular subgroups seem interesting because
they include all European and North American injecting drug user strains within the IIa and IIb subtypes, respectively. These
data confirm that European HTLV-II infection among drug users is probably derived from North America. They also suggest that
though a certain differentiation by restriction analysis in different subgroups is possible, carefully interpreted phylogenetic
analyses remain necessary. Using the likelihood ratio test, a molecular clock for the drug user strains was calibrated. A
fixation rate between 1.08 × 10−4 and 2.7 × 10−5 nucleotide substitutions per site per year was calculated for the IIa and IIb injecting drug user strains. This is the lowest
fixation rate so far reported for RNA viruses, including for HIV, which typically range between 10−2 and 10−4. 相似文献
47.
Marc Guaita Umberto Melia Montserrat Vallverdú Pere Caminal Isabel Vilaseca Josep M. Montserrat Carles Gaig Manel Salamero Joan Santamaria 《PloS one》2015,10(4)
Aim
The present study aimed to analyse the autonomic nervous system activity using heart rate variability (HRV) to detect sleep disordered breathing (SDB) patients with and without excessive daytime sleepiness (EDS) before sleep onset.Methods
Two groups of 20 patients with different levels of daytime sleepiness -sleepy group, SG; alert group, AG- were selected consecutively from a Maintenance of Wakefulness Test (MWT) and Multiple Sleep Latency Test (MSLT) research protocol. The first waking 3-min window of RR signal at the beginning of each nap test was considered for the analysis. HRV was measured with traditional linear measures and with time-frequency representations. Non-linear measures -correntropy, CORR; auto-mutual-information function, AMIF- were used to describe the regularity of the RR rhythm. Statistical analysis was performed with non-parametric tests.Results
Non-linear dynamic of the RR rhythm was more regular in the SG than in the AG during the first wakefulness period of MSLT, but not during MWT. AMIF (in high-frequency and in Total band) and CORR (in Total band) yielded sensitivity > 70%, specificity >75% and an area under ROC curve > 0.80 in classifying SG and AG patients.Conclusion
The regularity of the RR rhythm measured at the beginning of the MSLT could be used to detect SDB patients with and without EDS before the appearance of sleep onset. 相似文献48.
Marc C. Tahita Halidou Tinto Annette Erhart Adama Kazienga Robert Fitzhenry Chantal VanOvermeir Anna Rosanas-Urgell Jean-Bosco Ouedraogo Robert T. Guiguemde Jean-Pierre Van geertruyden Umberto D’Alessandro 《PloS one》2015,10(9)
Background
The emergence and spread of drug resistance represents one of the biggest challenges for malaria control in endemic regions. Sulfadoxine-pyrimethamine (SP) is currently deployed as intermittent preventive treatment in pregnancy (IPTp) to prevent the adverse effects of malaria on the mother and her offspring. Nevertheless, its efficacy is threatened by SP resistance which can be estimated by the prevalence of dihydropteroate synthase (dhps) and dihydrofolate reductase (dhfr) mutations. This was measured among pregnant women in the health district of Nanoro, Burkina Faso.Methods
From June to December 2010, two hundred and fifty six pregnant women in the second and third trimester, attending antenatal care with microscopically confirmed malaria infection were invited to participate, regardless of malaria symptoms. A blood sample was collected on filter paper and analyzed by PCR-RFLP for the alleles 51, 59, 108, 164 in the pfdhfr gene and 437, 540 in the pfdhps gene.Results
The genes were successfully genotyped in all but one sample (99.6%; 255/256) for dhfr and in 90.2% (231/256) for dhps. The dhfr C59R and S108N mutations were the most common, with a prevalence of 61.2% (156/255) and 55.7% (142/255), respectively; 12.2% (31/255) samples had also the dhfr N51I mutation while the I164L mutation was absent. The dhps A437G mutation was found in 34.2% (79/231) isolates, but none of them carried the codon K540E. The prevalence of the dhfr double mutations NRNI and the triple mutations IRNI was 35.7% (91/255) and 11.4% (29/255), respectively.Conclusion
Though the mutations in the pfdhfr and pfdhps genes were relatively common, the prevalence of the triple pfdhfr mutation was very low, indicating that SP as IPTp is still efficacious in Burkina Faso. 相似文献49.
Ifedayo M. O. Adetifa Abdul Khalie Muhammad David Jeffries Simon Donkor Martien W. Borgdorff Tumani Corrah Umberto D’Alessandro 《PloS one》2015,10(10)
Background
A Tuberculin skin test (TST) survey was conducted to assess the prevalence of latent TB Infection (LTBI) and to estimate the annual risk of M. tuberculosis infection (ARTI) in Gambian school children. The results are expected to contribute to understanding of Tuberculosis epidemiology in The Gambia.Methods
This was a nationwide, multi-cluster survey in children aged 6–11 years. Districts, 20 of 37, were selected by probability proportional to size and schools by simple random sampling. All TST were performed using the Mantoux method. Height and weight measurements were obtained for all participants. We calculated prevalence of LTBI using cut-off points of 10mm, the mirror and mixture modelling methods.Results
TST readings were completed 13,386 children with median age of 9 years (interquartile range [IQR] 8–10 years). Mixture analysis yielded a cut-off point of 12 mm, and LTBI prevalence of 6.9% [95%CI 6.47–7.37] and the ARTI was 0.75% [95%CI 0.60–0.91]. LTBI was associated gender and urban residence (p <0.01). Nutritional status was not associated with non-reactive TST or sizes of TST indurations. ARTI did not differ significantly by age, gender, BCG vaccination or residence.Conclusions
This estimates for LTBI prevalence and ARTI were low but this survey provides updated data. Malnutrition did not affect estimates of LTBI and ARTI. Given the low ARTI in this survey and the overlapping distribution of indurations with mixture modelling, further surveys may require complementary tests such as interferon gamma release assays or novel diagnostic tools. 相似文献50.
Umberto Melia Montserrat Vallverdú Xavier Borrat Jose Fernando Valencia Mathieu Jospin Erik Weber Jensen Pedro Gambus Pere Caminal 《PloS one》2015,10(4)
The level of sedation in patients undergoing medical procedures evolves continuously, affected by the interaction between the effect of the anesthetic and analgesic agents and the pain stimuli. The monitors of depth of anesthesia, based on the analysis of the electroencephalogram (EEG), have been progressively introduced into the daily practice to provide additional information about the state of the patient. However, the quantification of analgesia still remains an open problem. The purpose of this work is to improve the prediction of nociceptive responses with linear and non-linear measures calculated from EEG signal filtered in frequency bands higher than the traditional bands. Power spectral density and auto-mutual information function was applied in order to predict the presence or absence of the nociceptive responses to different stimuli during sedation in endoscopy procedure. The proposed measures exhibit better performances than the bispectral index (BIS). Values of prediction probability of Pk above 0.75 and percentages of sensitivity and specificity above 70% were achieved combining EEG measures from the traditional frequency bands and higher frequency bands. 相似文献