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121.
Das als Verbrennungsprodukt entstehende Schwefeldioxid belastet unsere Atmosphäre als Schadgas in zunehmendem Maße. Begasung von Blättern höherer Pflanzen mit SO2 führt zu akuten (Wasseraustritt aus den Zellen in die Interzellularräume) und chronischen (Chlorophyllabbau, Nekrosen) Schädigungen. SO2 hemmt die Photosynthese und beeinträchtigt den Mechanismus der Spaltöffnungsregulation: die Rate der Wasserdampfabgabe, CO2-Aufnahme und SO2-Aufnahme verläuft nach SO2-Beimischung zur Atmosphäre in Form einer gedämpften Schwingung Bisulfitverbindungen (Bildung bei Lösung von SO2 in Waser) wirken schon in geringen Konzentrationen (ab 0,5 mM) auf 0,5 mm dicke Blattstreifen, bevor äußerlich sichtbare Schädigungen auftreten: Die Wirkung der Bisulfitverbindungen wird als unspezifischer Membraneffekt diskutiert, dem bei höheren Konzentrationen spezifischere Enzymeffekte überlagert sein können
- a ) Hemmung der 14CO2-Fixierung bei C3- und C4-Pflanzen;
- b ) Hemmung des 14C-Einbaus in die CO2-Kurzzeit-Fixierungsprodukte, d. h. Hemmung der Synthese von 3-Phosphoglycerinsäure (3-PGS) bei C3-Pflanzen und von Malat und Aspartat bei C4-Pflanzen;
- c ) Steigerung der Synthese von 3-PGS bei Amaranthus durch 5 mM Glyoxal-Na-bisulfit, da CO2 wohl direkt — nach Hemmung der Phosphoenolpyruvat-Carboxylase im Mesophyll — in den Leitbündelscheiden fixiert wird;
- d ) Verminderung des ATP-Spiegels im Licht und im Dunkeln;
- e ) Hemmung der lichtinduzierten pH-Änderungen von Blattgewebe in ungepuffertem Medium;
- f ) Hemmung der Chloridaufnahme bei C3- und C4-Pflanzen im Licht wie im Dunkeln
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123.
Veronika Anita Deák Philipp Skroblin Carsten Dittmayer Klaus-Peter Knobeloch Sebastian Bachmann Enno Klussmann 《The Journal of biological chemistry》2016,291(2):681-690
A-kinase anchoring proteins (AKAPs) represent a family of structurally diverse proteins, all of which bind PKA. A member of this family is glycogen synthase kinase 3β (GSK3β) interaction protein (GSKIP). GSKIP interacts with PKA and also directly interacts with GSK3β. The physiological function of the GSKIP protein in vivo is unknown. We developed and characterized a conditional knock-out mouse model and found that GSKIP deficiency caused lethality at birth. Embryos obtained through Caesarean section at embryonic day 18.5 were cyanotic, suffered from respiratory distress, and failed to initiate breathing properly. Additionally, all GSKIP-deficient embryos showed an incomplete closure of the palatal shelves accompanied by a delay in ossification along the fusion area of secondary palatal bones. On the molecular level, GSKIP deficiency resulted in decreased phosphorylation of GSK3β at Ser-9 starting early in development (embryonic day 10.5), leading to enhanced GSK3β activity. At embryonic day 18.5, GSK3β activity decreased to levels close to that of wild type. Our findings reveal a novel, crucial role for GSKIP in the coordination of GSK3β signaling in palatal shelf fusion. 相似文献
124.
Jürgen Hartleb York Damm Rüdiger Arndt Enno Christophers Eggert Stockfleth 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1999,727(1-2)
5-S-Cysteinyldopa (5-SCD) in plasma and urine was determined by means of a newly developed method. This method incorporates optimized conditions for blood collection and storage, as well as a new extraction and separation technique, required for the strong oxidation and light sensitive 5-SCD. The new aspects of the method are the following: immediate centrifugation and freezing of the samples after blood collection, fully automatical solid-phase extraction (SPE) with phenylboronic acid (PBA) cartridges and immediate HPLC injection of the eluate, nearly complete exclusion of light and air–oxygen during extraction, constant sample cooling, use of the more suitable internal standard 5-S-
-cysteinyldopa and easy, sensitive and selective HPLC conditions (RP18-column with isocratic separation and electrochemical detection). The method has a linear range from 0.25 to 50 μg l−1 and 25 to 5000 μg l−1 for plasma and urine samples, respectively, a limit of detection of 0.17 μg l−1, intra-assay variabilities from 1.7 to 3.6%, inter-assay variabilities from 4.0 to 18.3% and an average relative recovery of 103.5% for plasma and 105.4% for urine samples. In our study the measured 5-SCD concentrations of patients with melanomas at various stages correlated better with their clinical pictures than described in literature up to date. The results were obtained in comparison to patients with other skin tumors and in comparison to healthy control persons. 相似文献
125.
Sunil Suresh Abraha T. Gidey Towhid H. Chowdhury Sachin R. Rondiya Li Tao Jian Liu Bart Vermang Alexander R. Uhl 《Liver Transplantation》2024,14(10):2303309
A N, N-dimethylformamide and thiourea-based route is developed to fabricate submicron (0.55 and 0.75 µm) thick CuIn(S,Se)2 (CISSe) thin films for photovoltaic applications, addressing challenges of material usage, throughput, and manufacturing costs. However, reducing the absorber film thickness below 1 µm in a regular CISSe solar cell decreases the device efficiency due to losses at the highly-recombinative, and mediocre-reflective Mo/CISSe rear interface. For the first time, to mitigate the rear recombination losses, a novel rear contacting structure involving a surface passivation layer and point contact openings is developed for solution processed CISSe films and demonstrated in tangible devices. An atomic layer deposited Al2O3 film is employed to passivate the Mo/CISSe rear surface while precipitates formed via chemical bath deposition of CdS are used to generate nanosized point openings. Consequently, Al2O3 passivated CISSe solar cells show an increase in the open-circuit voltage (VOC) and short-circuit current density when compared to reference cells with equivalent absorber thicknesses. Notably, a VOC increase of 59 mV contributes to active area efficiencies of 14.2% for rear passivated devices with 0.75 µm thick absorber layers, the highest reported value for submicron-based solution processed, low bandgap CISSe solar cells. 相似文献
126.
127.
In this article, we propose a new method for computing rare maximal exact matches between multiple sequences. A rare match between k sequences S(1), ... , S(k) is a string that occurs at most t(i)-times in the sequence S(i), where the t(i) > 0 are user-defined thresholds. First, the suffix tree of one of the sequences (the reference sequence) is built, and then the other sequences are matched separately against this suffix tree. Second, the resulting pairwise exact matches are combined to multiple exact matches. A clever implementation of this method yields a very fast and space efficient program. This program can be applied in several comparative genomics tasks, such as the identification of synteny blocks between whole genomes. 相似文献
128.
Alexander A. Timoshin Diana Yu. Drobotova Vladimir L. Lakomkin Enno K. Ruuge Anatoly F. Vanin 《Nitric oxide》2008,19(4):338-344
It was found that microdialysis, i.e., passage of aqueous solutions of iron-N-methyl-d-glucamine dithiocarbamate complexes through dialysis fibers implanted into heart, kidney and liver tissues of narcotized rats, was accompanied by effective binding of the complexes to nitric oxide from interstitial fluid. The walls of dialysis fibers used in this study were permeable for compounds with molecular weight not exceeding 5 kDa. The dialyzate samples collected every 20 min and containing diamagnetic nitrosyl Fe3+-MGD adducts were reduced to the paramagnetic state with sodium dithionite; their concentration was measured by the EPR method. The basic level of the adducts, which represented mononitrosyl iron complexes with MGD (MNIC–MGD), in the dialyzate samples of all tested organs were similar (1 μМ). Treatment of animals with the water-soluble nitroglycerine analog Isoket or a low-molecular dinitrosyl iron thiosulfate complex as a NO donor increased the concentration of MNIC–MGD with going out into a plateau. The novel approach allows determination of nitric oxide levels in tissue interstitial fluid from concentration of MNIC–MGD formed during microdialysis. 相似文献
129.
Summary: We implemented a software tool called GENESIS for threedifferent genome rearrangement problems: Sorting a unichromosomalgenome by weighted reversals and transpositions (SwRT), sortinga multichromosomal genome by reversals, translocations, fusionsand fissions (SRTl), and sorting a multichromosomal genome byweighted reversals, translocations, fusions, fissions and transpositions(SwRTTl). Availability: Source code can be obtained by the authors, oruse the web interface http://www.uni-ulm.de/in/theo/research/genesis.html Contact: simon.gog{at}uni-ulm.de
Associate Editor: Chris Stoeckert 相似文献
130.
Antibody microarrays offer a powerful tool to screen for target proteins in complex samples. Here, we describe an approach for systematic analysis of serum, based on antibodies and using color-coded beads for the creation of antibody arrays in suspension. This method, adapted from planar antibody arrays, offers a fast, flexible, and multiplexed procedure to screen larger numbers of serum samples, and no purification steps are required to remove excess labeling substance. The assay system detected proteins down to lower picomolar levels with dynamic ranges over 3 orders of magnitude. The feasibility of this workflow was shown in a study with more than 200 clinical serum samples tested for 20 serum proteins. 相似文献