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951.
Felice Esposito Filippo Flavio Angileri Peter Kruse Luigi Maria Cavallo Domenico Solari Vincenzo Esposito Francesco Tomasello Paolo Cappabianca 《PloS one》2016,11(4)
BackgroundFibrin sealants are widely used in neurosurgery to seal the suture line, provide watertight closure, and prevent cerebrospinal fluid leaks. The aim of this systematic review is to summarize the current efficacy and safety literature of fibrin sealants in dura sealing and the prevention/treatment of cerebrospinal fluid leaks.MethodsA comprehensive electronic literature search was run in the following databases: Cochrane Database of Systematic Reviews, Cochrane Central Resister of Controlled Trials, clinicaltrials.gov, MEDLINE/PubMed, and EMBASE. Titles and abstracts of potential articles of interest were reviewed independently by 3 of the authors.ResultsA total of 1006 database records and additional records were identified. After screening for duplicates and relevance, a total of 78 articles were assessed by the investigators for eligibility. Thirty-eight were excluded and the full-text of 40 articles were included in the qualitative synthesis. Seven of these included only safety data and were included in the safety assessment. The remaining 33 articles included findings from 32 studies that enrolled a total of 2935 patients who were exposed to fibrin sealant. Among these 33 studies there were only 3 randomized controlled trials, with the remaining being prospective cohort analysis, case controlled studies, prospective or retrospective case series. One randomized controlled trial, with 89 patients exposed to fibrin sealant, found a greater rate of intraoperative watertight dura closure in the fibrin sealant group than the control group (92.1% versus 38.0%, p<0.001); however, post-operative cerebrospinal fluid leakage occurred in more fibrin sealant than control patients (6.7% versus 2.0%, p>0.05). Other clinical trials evaluated the effect of fibrin sealant in the postoperative prevention of cerebrospinal fluid leaks. These were generally lower level evidence studies (ie, not prospective, randomized, controlled trials) that were not designed or powered to demonstrate a significant advantage to fibrin sealant use. Two small case series studies evaluated the effect of fibrin sealants in persistent cerebrospinal fluid leak treatment, but did not establish firm efficacy conclusions. Specific adverse reports where fibrin sealants were used for dura sealing were limited, with only 8 cases reported in neurosurgical procedures since 1987 and most reporting only a speculative relationship/association with fibrin sealant exposure.ConclusionsA major finding of this systematic literature review is that there is a paucity of randomized studies that have evaluated the effectiveness and safety of fibrin sealants in providing intraoperative watertight dura closure and post-operative cerebrospinal fluid leakage. Among the limited studies available, evidence from a single randomized, controlled trial indicates that fibrin sealants provide a higher rate of intraoperative watertight closure of the dura suture line than control, albeit with a higher rate of postoperative cerebrospinal fluid leakage. Evidence from non-randomized, controlled trials suggests that fibrin sealants may be effective in preventing cerebrospinal fluid leaks with an acceptable safety profile. There is a substantial need for randomized, controlled clinical trials or well-designed prospective observational trials where the conduct of a randomized trial is not feasible to fully assess the impact of fibrin sealant utilization on the rates of intraoperative dura closure, postoperative cerebrospinal leakage, and safety. 相似文献
952.
953.
Saino Nicola; Galeotti Paolo; Sacchi Roberto; Moller Anders Pape 《Behavioral ecology》1997,8(4):364-371
Male secondary sexual characters may have evolved as intra-or intersexual signals of male phenotypic or genetic quality.In birds, singing performance may have the function to honestlyreveal health and vigor of individual males. Infectious diseasesand poor body conditions would therefore be expected to negativelyinfluence singing performance. Since bird pathogens are knownto elicit both a humoral and a cell-mediated immune response,it can be predicted that a negative relationship exists betweensinging performance and activity of the immune system. Thisprediction was tested for the first time in this correlationalstudy. The relationships between song rate and features andhematological variables (concentration of leukocytes in peripheralblood, ratio of gamma-globulins to total plasma proteins, bloodcell sedimentation rate, hematocrit) and body condition wereanalyzed in a population of bam swallows (Hirundo rustica).Song rate was negatively correlated with lymphocyte concentrationand with the ratio of gamma-globulins to plasma proteins. Spectrographicanalysis showed that features of song were not significantlycorrelated with hematological variables or body condition. Thelevel of circulating testosterone was not correlated with songrate nor hematological variables. This study is the first toshow a correlation between a bird's singing performance andhematological profile and suggests that song rate of male barnswallows may reflect their health status. Song in this speciesmight thus have evolved because it allows prospecting femalesto assess aspects of phenotypic and/or genetic quality of potentialmates 相似文献
954.
955.
Maurizio Sajeva Francesca Grisafi Anna Maria Ferrarella Paolo D'italia 《Plant biosystems》2013,147(5):911-917
Abstract Starch was enzymatically assayed in the hypocotyls of radish (Raphanus sativus L.) seedlings grown in water or chloramphenicol (CAP) 1 × 104. CAP inhibits starch formation and its effect is related to the concentration. Both CAP- and water-grown hypocotyls are able to accumulate starch when sucrose is supplied in the medium, thus suggesting that the damage caused by CAP to the amyloplast is not irreversible. Apical segments of both water- and CAP- grown hypocotyls accumulate starch upon incubation in sucrose solutions while basal segments are unable to accumulate starch even in the presence of sucrose. The authors suggest that the basal segments are unable to perform sucrose uptake or that the amyloplast is incapable to starch synthesis. In any case the inability of the basal segment to perform sucrose uptake is independent of CAP. These findings confirm that the radish hypocotyls is not homogeneous along its axes. 相似文献
956.
957.
Marta Grech Paolo Sartor Elizabet Estallo Francisco Ludue?a-Almeida Walter Almirón 《Memórias do Instituto Oswaldo Cruz》2013,108(6):772-777
The aims of this study were to characterise the ground-level larval habitats of
the mosquito Culex quinquefasciatus, to determine the
relationships between habitat characteristics and larval abundance and to
examine seasonal larval-stage variations in Córdoba city. Every two weeks for
two years, 15 larval habitats (natural and artificial water bodies, including
shallow wells, drains, retention ponds, canals and ditches) were visited and
sampled for larval mosquitoes. Data regarding the water depth, temperature and
pH, permanence, the presence of aquatic vegetation and the density of collected
mosquito larvae were recorded. Data on the average air temperatures and
accumulated precipitation during the 15 days prior to each sampling date were
also obtained. Cx. quinquefasciatus larvae were collected
throughout the study period and were generally most abundant in the summer
season. Generalised linear mixed models indicated the average air temperature
and presence of dicotyledonous aquatic vegetation as variables that served as
important predictors of larval densities. Additionally, permanent breeding sites
supported high larval densities. In Córdoba city and possibly in other highly
populated cities at the same latitude with the same environmental conditions,
control programs should focus on permanent larval habitats with aquatic
vegetation during the early spring, when the Cx.
quinquefasciatus population begins to increase. 相似文献
958.
959.
Walter Fratta Giampaolo Mereu Paolo Chessa Elisabetta Paglietti GianLuigi Gessa 《Life sciences》1976,18(10):1157-1165
The effect of different benzodiazepines on food intake was studied in cats which had been trained to eat their daily food within 3 hours, under conditions in which emotional factors were not present. When benzodiazepines were administered (at a dose ranging from 0.1 to 3 mg/Kg) before feeding, they increased both the total amount of food eaten and also the rate at which food was injested. When they were administered at the end of the feeding period, these compounds made the animals resume eating voraciously. The order of decreasing potency of the benzodiazepines tested was: oxazepam, N-methyl-lorazepam, diazepam, chlordiazepoxide, pinazepam, medazepam. Oxazepam (3 mg/Kg) stimulated maximally the food intake, even when administered up to 12 hours before feeding. Finally, oxazepam antagonized the anorexigenic effect of d-amphetamine, but did not influence amphetamine-induced hyperactivity and stereotyped behavior. 相似文献
960.