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81.
Novel method for early signs of clinical shock detection by monitoring blood capillary/vessel spatial pattern 下载免费PDF全文
Rajesh Kanawade Florian Klämpfl Max Riemann Christian Knipfer Katja Tangermann‐Gerk Michael Schmidt Florian Stelzle 《Journal of biophotonics》2014,7(10):841-849
The ability to monitor capillary/vessel spatial patterns and local blood volume fractions is critical in clinical shock detection and its prevention in Intensive Care Units (ICU). Although the causes of shock might be different, the basic abnormalities in pathophysiological changes are the same. To detect these changes, we have developed a novel method based on both spectrally and spatially resolved diffuse reflectance spectra. The preliminary study has shown that this method can monitor the spatial distribution of capillary/vessel spatial patterns through local blood volume fractions of reduced hemoglobin and oxyhemoglobin. This method can be used as a real‐time and non‐invasive tool for the monitoring of shock development and feedback on the therapeutic intervention. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
82.
Jasmonates (JAs) are plant hormones which are crucial for the response of plants to several biotic and abiotic stresses. Beside this important function, they are involved in several developmental processes throughout plant life. In this short review, we would like to summarize the recent findings about the function of JAs in photomorphogenesis with a main focus on the model plant rice. Early plant development is determined to a large extent by light. Depending on whether seedlings are raised in darkness or in light, they show a completely different appearance which led to the terms skoto- and photomorphogenesis, respectively. The different appearance depending on the light conditions has been used to screen for mutants in photoperception and signalling. By this approach, mutants for several photoreceptors and in the downstream signalling pathways could be isolated. In rice, we and others isolated mutants with a very intriguing phenotype. The mutated genes have been cloned by map-based cloning, and all of them encode for JA biosynthesis genes. The most bioactive form of JAs identified so far is the amino acid conjugate jasmonoyl-isoleucin (JA-Ile). In order to conjugate JA to Ile, an enzyme of the GH3 family, JASMONATE RESISTANT 1, is required. We characterized mutants of OsJAR1 on a physiological and biochemical level and found evidence for redundantly active enzymes in rice. 相似文献
83.
The jasmonate pathway mediates salt tolerance in grapevines 总被引:1,自引:0,他引:1
84.
Sjöstedt J Koch-Schmidt P Pontarp M Canbäck B Tunlid A Lundberg P Hagström A Riemann L 《Applied and environmental microbiology》2012,78(5):1361-1369
A bacterial community may be resistant to environmental disturbances if some of its species show metabolic flexibility and physiological tolerance to the changing conditions. Alternatively, disturbances can change the composition of the community and thereby potentially affect ecosystem processes. The impact of disturbance on the composition of bacterioplankton communities was examined in continuous seawater cultures. Bacterial assemblages from geographically closely connected areas, the Baltic Sea (salinity 7 and high dissolved organic carbon [DOC]) and Skagerrak (salinity 28 and low DOC), were exposed to gradual opposing changes in salinity and DOC over a 3-week period such that the Baltic community was exposed to Skagerrak salinity and DOC and vice versa. Denaturing gradient gel electrophoresis and clone libraries of PCR-amplified 16S rRNA genes showed that the composition of the transplanted communities differed significantly from those held at constant salinity. Despite this, the growth yields (number of cells ml(-1)) were similar, which suggests similar levels of substrate utilization. Deep 454 pyrosequencing of 16S rRNA genes showed that the composition of the disturbed communities had changed due to the recruitment of phylotypes present in the rare biosphere of the original community. The study shows that members of the rare biosphere can become abundant in a bacterioplankton community after disturbance and that those bacteria can have important roles in maintaining ecosystem processes. 相似文献
85.
Leptonemella species represent a dominant element of the nematode fauna in sulfidic, deep sediment layers on the sandy shore of Sylt.
Based on collections sampled here in 1991–1999, a taxonomic treatise is presented on the three co-existing species, Leptonemella aphanothecae Gerlach, 1950, the closely related L. vicina sp. nov., and L. gorgo Gerlach, 1950. The high incidence of pseudohermaphrodites in the material, mostly functional females with a male copulatory
apparatus, is remarkable. The highest population densities of Leptonemella spp. (up to 73 individuals/10 ml sand) were found near polychaete burrows. Because of the great spatial and temporal variations
in the oxygen/sulfide regime of these microhabitats, and because of the strong adhesive capabilities of Leptonemella spp., which can anchor themselves firmly to sand grains using caudal glands, we propose that a hemisessile life strategy
is employed by these nematodes to fulfill the metabolic needs of their sulfide-oxidizing ectosymbionts.
Communicated by K. Reise 相似文献
86.
Respiration in eutrophic lakes: the contribution of bacterioplankton and bacterial growth yield 总被引:5,自引:0,他引:5
Schwaerter Steen; Sondergaard Morten; Riemann Bo; Jensen Lars Moller 《Journal of plankton research》1988,10(3):515-531
The contribution of bacterioplankton to total plankton respirationwas measured in two eutrophic Danish lakes and in experimentalenclosures treated with planktivorous fish and nutrients. Bacterialrespiration was calculated from measured oxygen uptake ratesin particles passing a 1.0-µm pore size filter, the rateswere then corrected for the size distribution of glucose uptake.During summer the respiration of the planktonic bacteria contributed{small tilde}50% of the community respiration in the two lakes.Prolific phytoplankton growth induced by biomanipulation andnutrient addition created situations where the contributionof the bacteria decreased to 20%. High bacterial contributionsto community respiration were found when the phytoplankton biomassdecreased. Simultaneous measurements of bacterial respirationand production (by means of [3H]thymidine incorporation) allowedan estimation of bacterial growth yield, which ranged from 9to 66%. In the two lakes the growth yield was constant witha mean of 29 ± 5% (±SD, RQ = 1). The variabilityof the growth yield was larger in the enclosures. The wide range(966%) was mainly caused by changes in bacterial netproduction without concomitant changes in respiration. The discussionincludes an evaluation of the oxygen uptake method in size fractionatedsamples and the availability of labile organic substrates asa factor controlling bacterial growth yield.
Present address: Institute of Biology and Chemistry, Universityof Roskilde, P. Box 260, DK-4000 Roskilde, Denmark 相似文献
87.
Ketosis data from the Health Card System, and interview data regarding feeding, housing, management and care were the basis for an epidemiological study in 306 Norwegian dairy herds. Management and care were studied by means of an overall care index. The index was based on 20 questions which provided information about the general standard of management and care. Care was the factor having the most pronounced effect on the treatment rate of ketosis. Highest rates were seen in herds with a high standard of management and care, and lowest rates were seen in herds with a low standard. Most ketosis was found in the mountain valley districts Nord-Østerdal/Gudbrandsdal and Valdres, and least in the lowland coastal district Rogaland. The treatment rate decreased with increasing herd size, and with increasing number of different feedstuffs used. Extra provision of feed concentrates between the morning and evening chores was associated with a lower treatment rate. Also associated with a lower treatment rate was the participation by the farmer’s wife in the daily chores. 相似文献
88.
A Rai M Riemann F Gustafsson N H Holstein-Rathlou C Torp-Pedersen 《Hormones et métabolisme》2008,40(9):651-654
A conducted vasomotor response (CVR) is characterized by the spread of vasoconstriction or vasodilatation both up- and downstream from a local stimulation site in the microcirculation. It is believed to coordinate vasomotor responses within the microcirculation, and to contribute to the control of the major feed arteries to a given organ or tissue. Microvascular disease is a common and severe complication in diabetes, and we therefore studied CVR in streptozotocin (STZ) diabetic mice to examine whether changes in CVR might have a role in the pathophysiology of microvascular dysfunction in diabetes. The mouse cremasteric arterioles were stimulated locally with KCl and the resulting local response as well as conducted responses at 500 mum and 1000 mum were measured in control and STZ treated mice. Diabetes (n=8) induced by intraperitoneal injection of STZ in a dose of 100 mg/kg (mean blood glucose 16.8+/-2.1 mmol/l) decreased the conduction of vasoconstriction from 27.3+/-1.1% to 21.4+/-1.6% at 500 mum (p<0.01) and from 17.4+/-1.0% to 9.8+/-1.1% at 1000 mum (p<0.01) as compared with control (n=9). Treatment with either the protein kinase C beta II inhibitor (LY341684) or the oxygen radical scavenger tempol, did not improve the decreased conduction of vasoconstriction, but when administered together, the conduction of vasoconstriction was improved from 21.4+/-1.6% to 26.5+/-0.8% at 500 mum and 9.8+/-1.1% to 16.5+/-0.7% at 1000 mum (p<0.01). We conclude that STZ induced diabetes reduces conducted vasoconstriction to KCl in mouse cremasteric arterioles, and combined treatment with both an oxygen radical scavenger and a protein kinase C beta II inhibitor improves the reduced conducted vasoconstriction. 相似文献
89.
Martin Klingenspor Tobias Fromme David A. Hughes Lars Manzke Elias Polymeropoulos Tobias Riemann Magdalene Trzcionka Verena Hirschberg Martin Jastroch 《BBA》2008,1777(7-8):637-641
Brown adipose tissue serves as a thermogenic organ in placental mammals to defend body temperature in the cold by nonshivering thermogenesis. The thermogenic function of brown adipose tissue is enabled by several specialised features on the organ as well as on the cellular level, including dense sympathetic innervation and vascularisation, high lipolytic capacity and mitochondrial density and the unique expression of uncoupling protein 1 (UCP1). This mitochondrial carrier protein is inserted into the inner mitochondrial membrane and stimulates maximum mitochondrial respiration by dissipating proton-motive force as heat. Studies in knockout mice have clearly demonstrated that UCP1 is essential for nonshivering thermogenesis in brown adipose tissue. For a long time it had been presumed that brown adipose tissue and UCP1 emerged in placental mammals providing them with a unique advantage to survive in the cold. Our subsequent discoveries of UCP1 orthologues in ectotherm vertebrates and marsupials clearly refute this presumption. We can now initiate comparative studies on the structure–function relationships in UCP1 orthologues from different vertebrates to elucidate when during vertebrate evolution UCP1 gained the biochemical properties required for nonshivering thermogenesis. 相似文献
90.
From the early Famennian of the Montagne Noire 19 different morphotypes of probably phyllocarid (Crustacea) affinities are
described. Apart from formerly unknown enamel-like structures that veil the uppermost tips of the denticles on most of the
gnathal lobe morphs, the stratigraphic implications concerning extinction behaviour across the Kellwasser mass extinction
event and during early Famennian diversification are discussed. In addition, phyllocarids in the Famennian seem to form a
useful stratigraphic tool for biostratigraphical correlation. Therefore, three basal Famennian phyllocarid assemblage zones
are distinguished.
相似文献