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751.
Jan H. Stock 《Hydrobiologia》1995,312(1):37-45
Four species of Copepoda Poecilostomatoida are recorded from the mantle cavity of bivalve molluscs collected in West New Guinea (Irian Barat, Indonesia). Two of these are new to science: Pseudanthessius dimorphus and Lichomolgus hoi n. spp. 相似文献
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Fabian Mittermeier Miriam Bäumler Prasika Arulrajah José de Jesús García Lima Sebastian Hauke Anna Stock Dirk Weuster-Botz 《Engineering in Life Science》2023,23(1):e2100152
The application of artificial microbial consortia for biotechnological production processes is an emerging field in research as it offers great potential for the improvement of established as well as the development of novel processes. In this review, we summarize recent highlights in the usage of various microbial consortia for the production of, for example, platform chemicals, biofuels, or pharmaceutical compounds. It aims to demonstrate the great potential of co-cultures by employing different organisms and interaction mechanisms and exploiting their respective advantages. Bacteria and yeasts often offer a broad spectrum of possible products, fungi enable the utilization of complex lignocellulosic substrates via enzyme secretion and hydrolysis, and microalgae can feature their abilities to fixate CO2 through photosynthesis for other organisms as well as to form lipids as potential fuelstocks. However, the complexity of interactions between microbes require methods for observing population dynamics within the process and modern approaches such as modeling or automation for process development. After shortly discussing these interaction mechanisms, we aim to present a broad variety of successfully established co-culture processes to display the potential of artificial microbial consortia for the production of biotechnological products. 相似文献
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Kjell Youngren Elisabeth Jeanclos Hana Aviv Masayuki Kimura Jeffrey Stock Moneer Hanna J. Skurnick Arlene Bardeguez A. Aviv 《Human genetics》1998,102(6):640-643
Telomere length, measured by terminal restriction fragments, was examined in tissues from human fetuses of gestational ages
estimated as 15–19 weeks. The length of telomeres was similar in most fetal tissues. However, there were significant variations
in telomere length among fetuses, with no apparent relationship between gestational age and telomere length. We conclude that
synchrony in telomere length exists among tissues of the human fetus. This synchrony is apparently lost during extrauterine
life.
Received: 12 January 1998 / Accepted: 19 March 1998 相似文献
757.
Morphological diversification during adaptive radiation may depend on factors external or internal to the lineage. We provide evidence for the latter in characiform fishes (tetras and piranhas), which exhibit extensive dental diversity. Phylogenetic character mapping supported regain of lost teeth as contributing to this diversity. To test for latent potential for dentition that would facilitate its evolutionary expansion, we overexpressed a tooth initiation signal, the tumour necrosis factor pathway ligand ectodysplasin, in a model characiform, the Mexican tetra (Astyanax mexicanus). This manipulation resulted in extensive ectopic dentition, in contrast with its previously reported limited effect in the zebrafish (Danio rerio). Tooth location in the order Cypriniformes, to which the zebrafish belongs, is much more restricted than in characiforms, a pattern that may be explained by differences in the retention of ancestral developmental potential. Our results suggest that differences in evolvability between lineages may lead to contrasting patterns of diversification. 相似文献
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759.
Mechanisms of receptor function and the molecular biology of information processing in bacteria 总被引:6,自引:0,他引:6
J Stock 《BioEssays : news and reviews in molecular, cellular and developmental biology》1987,6(5):199-203
Bacteria adapt to changes in their environment by altering their metabolism, turning on and off genes, and moving toward favorable conditions. Recent results indicate that a common molecular logic may underlie the decision-making processes by which these simple cells adjust to their surroundings. 相似文献
760.
Jane E. Norman John Norrie Graeme MacLennan David Cooper Sonia Whyte Sue Chowdhry Sarah Cunningham-Burley Xue W. Mei Joel B. E. Smith Andrew Shennan Stephen C. Robson Steven Thornton Mark D. Kilby Neil Marlow Sarah J. Stock Phillip R. Bennett Jane Denton 《PLoS medicine》2021,18(3)
BackgroundPreterm-labour-associated preterm birth is a common cause of perinatal mortality and morbidity in twin pregnancy. We aimed to test the hypothesis that the Arabin pessary would reduce preterm-labour-associated preterm birth by 40% or greater in women with a twin pregnancy and a short cervix.Methods and findingsWe conducted an open-label randomised controlled trial in 57 hospital antenatal clinics in the UK and Europe. From 1 April 2015 to 14 February 2019, 2,228 women with a twin pregnancy underwent cervical length screening between 18 weeks 0 days and 20 weeks 6 days of gestation. In total, 503 women with cervical length ≤ 35 mm were randomly assigned to pessary in addition to standard care (n = 250, mean age 32.4 years, mean cervical length 29 mm, with pessary inserted in 230 women [92.0%]) or standard care alone (n = 253, mean age 32.7 years, mean cervical length 30 mm). The pessary was inserted before 21 completed weeks of gestation and removed at between 35 and 36 weeks or before birth if earlier. The primary obstetric outcome, spontaneous onset of labour and birth before 34 weeks 0 days of gestation, was present in 46/250 (18.4%) in the pessary group compared to 52/253 (20.6%) following standard care alone (adjusted odds ratio [aOR] 0.87 [95% CI 0.55–1.38], p = 0.54). The primary neonatal outcome—a composite of any of stillbirth, neonatal death, periventricular leukomalacia, early respiratory morbidity, intraventricular haemorrhage, necrotising enterocolitis, or proven sepsis, from birth to 28 days after the expected date of delivery—was present in 67/500 infants (13.4%) in the pessary group compared to 76/506 (15.0%) following standard care alone (aOR 0.86 [95% CI 0.54–1.36], p = 0.50). The positive and negative likelihood ratios of a short cervix (≤35 mm) to predict preterm birth before 34 weeks were 2.14 and 0.83, respectively. A meta-analysis of data from existing publications (4 studies, 313 women) and from STOPPIT-2 indicated that a cervical pessary does not reduce preterm birth before 34 weeks in women with a short cervix (risk ratio 0.74 [95% CI 0.50–1.11], p = 0.15). No women died in either arm of the study; 4.4% of babies in the Arabin pessary group and 5.5% of babies in the standard treatment group died in utero or in the neonatal period (p = 0.53). Study limitations include lack of power to exclude a smaller than 40% reduction in preterm labour associated preterm birth, and to be conclusive about subgroup analyses.ConclusionsThese results led us to reject our hypothesis that the Arabin pessary would reduce the risk of the primary outcome by 40%. Smaller treatment effects cannot be ruled out.Trial registrationISRCTN Registry ISRCTN 02235181.ClinicalTrials.gov .Jane Norman and co-workers report an evaluation of a cervical pessary for prevention of preterm birth in women with a short cervix bearing twins. NCT02235181相似文献