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61.
Natural forest reserves provide a rare opportunity to study forest dynamics after the cessation of human management. Inventories were carried out in 1996 and 2006 in an oak (Quercus spp.) dominated forest reserve formerly managed as coppice forest using the Bitterlich sampling method, an inventory method with a fixed angle of sight to select trees based on their stem diameter. The total living stand volume increased from 245.2 to 276.5 m3/ha (+12.8%) over the 10-year period. This net increase resulted from the growth of individual trees (+3.7%), the ingrowths of young trees (+17.7%) and tree mortality between 1996 and 2006 (−8.6%). Tree mortality included 14.8 m3/ha of standing deadwood and 6.2 m3/ha of fallen deadwood. Stand dynamics differed among tree species: the volume of oak (Quercus spp.) increased due to strong growth and low mortality, whereas hornbeam (Carpinus betulus) showed a decrease in stand volume due to high mortality and low growth. The findings suggest an increase in oak dominance at the expense of hornbeam although inventories repeated over longer time periods would be needed for confirmation. Our data indicate that the Bitterlich sampling method can be used for assessing tree species dynamics and structural changes in natural forest reserves, but some important processes (seedling recruitment, wood decomposition) would need to be investigated separately.
Zusammenfassung  In einem von Eiche (Quercus spp.) dominierten Naturwaldreservat wurde in den Jahren 1996 und 2006 auf einer Fl?che von 29 ha eine Inventur mittels der Winkelz?hlprobe nach Bitterlich durchgeführt. Der Gesamtvorrat erh?hte sich in der 10-j?hrigen Beobachtungsperiode von 245.2 m3/ha auf 276.5 m3/ha. Im Durchschnitt konnten 14.8 m3/ha stehendes Totholz und 6.2 m3/ha liegendes Totholz ermittelt werden. Die Mortalit?tsrate lag zwischen 1996 und 2006 bei 8.6%. Hainbuche (Carpinus betulus) zeigte aufgrund der hohen Mortalit?t und dem geringen Einwuchs im Vergleich zur Eiche und den anderen Baumarten eine Abnahme im Gesamtvorrat. Die Ergebnisse erlauben einen Einblick in die dynamischen Prozesse unter nahezu natürlichen Bedingungen. Die Eignung der Winkelz?hlprobe für die Beurteilung der Dynamik und die Analyse von strukturellen Ver?nderungen wird kritisch diskutiert.
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Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system, which is heterogenous with respect to clinical manifestations and response to therapy. Identification of biomarkers appears desirable for an improved diagnosis of MS as well as for monitoring of disease activity and treatment response. MicroRNAs (miRNAs) are short non-coding RNAs, which have been shown to have the potential to serve as biomarkers for different human diseases, most notably cancer. Here, we analyzed the expression profiles of 866 human miRNAs. In detail, we investigated the miRNA expression in blood cells of 20 patients with relapsing-remitting MS (RRMS) and 19 healthy controls using a human miRNA microarray and the Geniom Real Time Analyzer (GRTA) platform. We identified 165 miRNAs that were significantly up- or downregulated in patients with RRMS as compared to healthy controls. The best single miRNA marker, hsa-miR-145, allowed discriminating MS from controls with a specificity of 89.5%, a sensitivity of 90.0%, and an accuracy of 89.7%. A set of 48 miRNAs that was evaluated by radial basis function kernel support vector machines and 10-fold cross validation yielded a specificity of 95%, a sensitivity of 97.6%, and an accuracy of 96.3%. While 43 of the 165 miRNAs deregulated in patients with MS have previously been related to other human diseases, the remaining 122 miRNAs are so far exclusively associated with MS. The implications of our study are twofold. The miRNA expression profiles in blood cells may serve as a biomarker for MS, and deregulation of miRNA expression may play a role in the pathogenesis of MS.  相似文献   
64.

Background

Internet-based self-management has shown to improve asthma control and asthma related quality of life, but the improvements were only marginally clinically relevant for the group as a whole. We hypothesized that self-management guided by weekly monitoring of asthma control tailors pharmacological therapy to individual needs and improves asthma control for patients with partly controlled or uncontrolled asthma.

Methods

In a 1-year randomised controlled trial involving 200 adults (18-50 years) with mild to moderate persistent asthma we evaluated the adherence with weekly monitoring and effect on asthma control and pharmacological treatment of a self-management algorithm based on the Asthma Control Questionnaire (ACQ). Participants were assigned either to the Internet group (n = 101) that monitored asthma control weekly with the ACQ on the Internet and adjusted treatment using a self-management algorithm supervised by an asthma nurse specialist or to the usual care group (UC) (n = 99). We analysed 3 subgroups: patients with well controlled (ACQ ≤ 0.75), partly controlled (0.75>ACQ ≤ 1.5) or uncontrolled (ACQ>1.5) asthma at baseline.

Results

Overall monitoring adherence was 67% (95% CI, 60% to 74%). Improvements in ACQ score after 12 months were -0.14 (p = 0.23), -0.52 (p < 0.001) and -0.82 (p < 0.001) in the Internet group compared to usual care for patients with well, partly and uncontrolled asthma at baseline, respectively. Daily inhaled corticosteroid dose significantly increased in the Internet group compared to usual care in the first 3 months in patients with uncontrolled asthma (+278 μg, p = 0.001), but not in patients with well or partly controlled asthma. After one year there were no differences in daily inhaled corticosteroid use or long-acting β2-agonists between the Internet group and usual care.

Conclusions

Weekly self-monitoring and subsequent treatment adjustment leads to improved asthma control in patients with partly and uncontrolled asthma at baseline and tailors asthma medication to individual patients'' needs.

Trial registration

Current Controlled Trials ISRCTN79864465  相似文献   
65.

Background  

The assembly and spatial organization of enzymes in naturally occurring multi-protein complexes is of paramount importance for the efficient degradation of complex polymers and biosynthesis of valuable products. The degradation of cellulose into fermentable sugars by Clostridium thermocellum is achieved by means of a multi-protein "cellulosome" complex. Assembled via dockerin-cohesin interactions, the cellulosome is associated with the cell surface during cellulose hydrolysis, forming ternary cellulose-enzyme-microbe complexes for enhanced activity and synergy. The assembly of recombinant cell surface displayed cellulosome-inspired complexes in surrogate microbes is highly desirable. The model organism Lactococcus lactis is of particular interest as it has been metabolically engineered to produce a variety of commodity chemicals including lactic acid and bioactive compounds, and can efficiently secrete an array of recombinant proteins and enzymes of varying sizes.  相似文献   
66.
Previously, treatment of Tamm-Horsfall glycoprotein (THp) from different donors with endo-beta-galactosidase has been shown to liberate a tetra- and a Sd(a)-active pentasaccharide, concluding the presence of N-linked carbohydrate chains containing additional N - acetyllactosamine units. These type of oligosaccharides were not found in a detailed structure elucidation of the carbohydrate moiety of THp of one male donor, suggesting a donor-specific feature for these type of structures. Therefore, THp was isolated from four healthy male donors and each subjected to endo-beta-galactosidase treatment in order to release these tetra- and Sd(a)-active pentasaccharide. Differences were observed in the total amount of released tetra- and Sda-active pentasaccharide of the used donors (42, 470, 478, 718 microg/100 mg THp), indicating that the presence of repeating N-acetyllactosamine units incorporated into the N-glycan moiety of THp is donor specific. Furthermore, a higher expression of the Sd(a) determinant on antennae which display N-acetyllactosamine elongation was observed, suggesting a better accessibility for the beta-N-acetylgalactosaminyltransferase. In order to characterize the N-glycans containing repeating N- acetyllactosamine units, carbohydrate chains were enzymatically released from THp and isolated. The tetraantennary fraction, which accounts for more than 33% of the total carbohydrate moiety of THp, was used to isolate oligosaccharides containing additional N - acetyllactosamine units. Five N-linked tetraantennary oligosaccharides containing a repeating N-acetyllactosamine unit were identified, varying from structures bearing four Sd(a) determinants to structures containing no Sd(a) determinant (see below). One compound was used in order to specify the branch location of the additional N- acetyllactosamine unit, and it appeared that only the Gal-6' and Gal-8' residues were occupied by a repeating N -acetyllactosamine unit.   相似文献   
67.
An ultrastructural overview of tubificid spermatozoa   总被引:1,自引:1,他引:0  
The spermatozoa of seven species of tubificid oligochaete were compared to those already described in order to supply spermatozoal characters for systematic work on Tubificidae. The spermatozoa of Clitellio arenarius (subfamily Tubificinae) resemble those of the two other known members of the subfamily (Tubifex tubifex and Tubificoides amplivasatus) in being of two different types and in showing the same morphology of acrosomes and nuclei. Among Phallodrilinae, the three gutless species Inanidrilus bulbosus, Inanidrilus leukodermatus and Olavius planus share with Bathydrilus formosus the shape of the nucleus and various characters of the acrosome, whereas Thalassodrilus prostatus is particular in having the acrosome vesicle external to the tube and the longest middle piece recorded in oligochaetes. Monopylephorus limosus and Rhizodrilus russus (Rhyacodrilinae) differ widely in acrosomal and nuclear characters: M. limosus has a twisted nucleus, whereas R. russus has an apically flanged nucleus with a conspicuous apical concavity and an endonuclear canal. The data published on spermatozoa of the Limnodriloidinae are reviewed.Department of Zoology University of Göteborg  相似文献   
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Summary Wolf-ungulate interactions were studied in the pristine deciduous and mixed forests of the Bialowiea National Park in 1985–1989. The study period included two severe and two mild winters. The community of ungulates inhabiting Bialowiea National Park consisted of red deer Cervus elaphus, 55% of all ungulates; wild boar Sus scrofa, 42%; and roe deer Capreolus capreolus, moose Alces alces, and European bison Bison bonasus, about 1% each. The average size of red deer groups increased from 2.7 (SD 2.35) in spring and summer to 6.9 (SD 6.84) in autumn and winter. In winter the group size of red deer was positively correlated with the depth of snow cover and negatively correlated with the mean daily temperature. Average group size of wild boar did not change significantly between seasons; it was 6.8 (SD 5.16) in spring and summer and 5.7 (SD 4.67) in autumn and winter. Analysis of 144 wolf scats showed that wolves preyed selectively on red deer. In October–April, Cervidae (mostly red deer) constituted 91% of biomass consumed by wolves, while wild boar made up only 8%. In May–September deer formed 77% of prey biomass, and the share of wild boar increased to 22%. In all seasons of the year wolves selected juveniles from deer and boar populations: 61% of red deer and 94% of wild boar of determined age recovered from wolves' scats were young <1 year old. Analysis of 117 carcasses of ungulates found in Bialowiea National Park showed that predation was the predominant mortality factor for red deer (40 killed, 10 dead from causes other than predation) and roe deer (4 killed, none dead). Wild boar suffered most from severe winter conditions (8 killed, 56 dead). The percentage of ungulates that had died from undernutrition and starvation in the total mortality was proportional to the severity of winter.  相似文献   
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