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961.
The kidney is an extremely complex organ with broad ranging functions in the body, including but not restricted to waste excretion,
ion and water balance, maintenance of blood pressure, glucose homeostasis, generation of erythropoietin and activation of
vitamin D. With diabetes, many of these integral processes are interrupted via a combination of haemodynamic and metabolic
changes including increases in the accumulation of proteins modified by advanced glycation, known as advanced glycation end
products (AGEs). Indeed, hyperglycaemia and the redox imbalances seen with diabetes are each independent accelerants for the
production of AGEs, which synergistically combine in this disorder. In addition, as kidney function declines, characterised
by a loss of glomerular filtration, the excretion of AGEs is decreased, possibly exacerbating renal injury by further elevating
the body’s tissue and circulating AGE pool. Therefore, it has become apparent that decreasing the accumulation of AGEs or
interrupting their downstream effects on the kidney, are desirable therapeutic targets for the treatment of diabetic renal
disease. 相似文献
962.
963.
Leif Egil Loe Christophe Bonenfant Erling L. Meisingset Atle Mysterud 《European Journal of Wildlife Research》2012,58(1):195-203
Species distribution models (SDMs) are popular in conservation and management of a wide array of taxa. Often parameterized
with coarse GIS-based environmental maps, they perform well in macro-ecological settings but it is debated if the models can
predict distribution within broadly suitable “known” habitats of interest to local managers. We parameterized SDMs with GIS-derived
environmental variables and location data from 82 GPS-collared female red deer (Cervus elaphus) from two study areas in Norway. Candidate GLM models were fitted to address the effect of spatial scale (landscape vs. home
range), sample size, and transferability between study areas, with respect to predictability (AUC) and explained variance
(Generalized R
2 and deviance). The landscape level SDM captured variation in deer distribution well and performed best on all diagnostic
measures of model quality, caused mainly by a trivial effect of avoidance of non-habitat (barren mountains). The home range
level SDMs were far less predictable and explained comparatively little variation in space use. Landscape scale models stabilized
at the low sample size of 5–10 individuals and were highly transferrable between study areas implying a low degree of individual
variation in habitat selection at this scale. It is important to have realistic expectations of SDMs derived from digital
elevation models and coarse habitat maps. They do perform well in highlighting potential habitat on a landscape scale, but
often miss nuances necessary to predict more fine-scaled distribution of wildlife populations. Currently, there seems to be
a trade-off between model quality and usefulness in local management. 相似文献
964.
Rb1 and Rg1 are the major ginsenosides in protopanaxadiol and protopanaxatriol. Their content in ginsenosides was 23.8 and 17.6%, respectively.
A total of 22 isolates of β-glucosidase producing microorganisms were isolated from the soil of a ginseng field using Esculin-R2A
agar. Among these isolates, the strain GH21 showed the strongest activities to convert ginsenoside Rb1 and Rg1 to minor ginsenosides compound-K and F1, respectively. Ginsenosides Rb1 and Rg1 bioconversion rates were 74.2 and 89.3%, respectively. Meanwhile, the results demonstrated that the ginsenoside Rg1 could change the biotransformation pathway of ginsenoside Rb1 by inhibiting the formation of the intermediate metabolite gypenoside-XVII. GH21 was identified as a Cladosporium cladosporioides species based on the internal transcribed spacers (ITS) ITS1-5.8S-ITS2 rRNA gene sequences constructed phylogenetic trees. 相似文献
965.
In this study, loop-mediated isothermal amplification (LAMP)-based molecular marker was developed for authentication of Catharanthus roseus, a medicinal plant. Samples of this plant were collected from different geographical locations in India. Random amplified
polymorphic deoxyribonucleic acid (DNA) analysis of collected samples was carried out with 25 random primers. A 610-bp DNA
fragment, common to all accessions, was eluted, cloned, and sequenced. Four LAMP primers were designed on the basis of sequence
of 610 bp DNA fragment. LAMP reaction, containing 10× Bst DNA polymerase reaction buffer, Bst DNA polymerase, four in-house designed primers, dNTPs, MgSO4, and betaine, was incubated at 65°C for 1 h. The resulting amplicon was visualized by adding SYBR Green I to the reaction
tube. The data showed confirmatory results. Since the assay method is simple, sensitive, and cost-effective, it is a feasible
method for identifying and authentication of C. roseus. 相似文献
966.
Anirban Guha Debashree Sengupta Girish Kumar Rasineni Attipalli Ramachandra Reddy 《Trees - Structure and Function》2012,26(3):903-918
The present study investigated drought-induced responses of non-enzymatic antioxidants in four diverse mulberry genotypes (Morus indica L. S-36, M-5, MR-2 and V-1). Inside the glasshouse, potted plants were subjected to four water regimes for 75 days: (a) control: pots maintained at 100% pot water holding capacity (PC) (b) low water stress: 75% PC (c) medium water stress: 50% PC and (d) high water stress: 25% PC. Photosynthetic leaf gas exchange and non-enzymatic antioxidants including α-tocopherol, ascorbic acid (AA), glutathione, proline and total carotenoids were measured in leaves at regular intervals. Amongst all, V-1 was relatively drought tolerant and showed exceeded accumulation of α-tocopherol and AA-glutathione pool in association with higher carotenoids and proline contents. Susceptible S-36, M-5 and MR-2 could not induce any significant up-regulation in AA-glutathione pool leading to endogenous loss of α-tocopherol and more lipid peroxidation. Reactive oxygen species (ROS) like hydrogen peroxide (H2O2) and superoxide (O2 · ?) showed apparent accumulation in water-stressed leaves and significantly contributed to lipid peroxidation in susceptible genotypes when compared to V-1. Our study demonstrated that proline, AA and glutathione were the major non-enzymatic antioxidants in mulberry with α-tocopherol and carotenoids as good additional indicators for drought stress tolerance. These non-enzymatic antioxidants can cumulatively render effective protection against oxidative damage and can be considered as reliable markers for screening drought-tolerant mulberry genotypes. 相似文献
967.
Numerous invasive aquatic species introductions can be traced to the aquarium trade. Many potentially harmful aquarium species
may be difficult to identify based on morphology alone. As such, some prohibited or invasive species may be available for
purchase if they are mislabeled as species without restrictions. Here we compare molecular identifications to internet vendors’
identifications for accessions of a popular genus of aquarium plants that are difficult to distinguish morphologically (Myriophyllum; watermilfoils). Specifically, we identified the extensive mislabeling of M. heterophyllum—an invasive species in the northeastern and western US. Furthermore, genotypes of M. heterophyllum found in our aquarium survey have also been found in invasive populations, suggesting their potential introduction through
escape from aquaria, water gardens, or nurseries. Two additional taxa were sold under incorrect names. Finally, our survey
revealed that Myriophyllum taxa present in the aquarium trade generally have poorly known distributions and ecologies, and therefore their invasive
potential is unknown. Our study confirms that molecular identification methods can provide a valuable tool to survey commercial
pathways for potentially harmful species that are otherwise difficult to identify. 相似文献
968.
A wide number of pesticides, including highly persistent organochlorine compounds, such as lindane (γ-Hexachlorocyclohexane),
have deteriorative effect on fauna and flora by inducing oxidative stress. Lindane induces cell damage by producing free radicals
and reactive oxygen species. Quercetin, a dietary flavonoid, is ubiquitous in fruits and vegetables and plays an important
role in human health by virtue of its antioxidant function. In this study the flavonoid quercetin was used to investigate
its antioxidative effect against lindane induced oxidative stress in rats. The level of lipid peroxidation, reduced glutathione
(GSH) were analysed in addition to the antioxidant enzymes such as catalase (CAT), glutathione peroxidase (GPx), superoxide
dismutase (SOD) and glutathione-s-transferase (GST) activities in the liver and kidney tissue. Levels of hepatic marker enzymes
in serum like Aspartate transaminase (AST), Alanine transaminase (ALT), Alkaline phosphatase (ALP) and Lactate dehydrogenase
(LDH) and renal markers like serum creatinine and serum urea were estimated. Administration of Lindane induced histopathological
alterations and increased levels of serum hepatic and renal markers and malondialdehyde (MDA) with a significant decrease
in GSH content and CAT, SOD, GPx and GST activities. Cotreatment of quercetin along with lindane significantly decreased the
lindane induced alteration in histology, serum hepatic and renal markers and MDA and also improved the cellular antioxidant
status. The results show that Quercetin ameliorates Lindane induced oxidative stress in liver and kidney. The quercetin exhibited
chemopreventive effect when administered along with lindane. 相似文献
969.
Structural changes of tissues in unpollinated ovaries of Pisum sativum L. cv. Alaska after treatment with different plant growth substances (gibberellic acid, 2,4-dichlorophenoxyacetic acid, and 6-benzyladenine) or decapitation of the plant were studied. All the treatments resulted in the prevention of cellular disorganization associated with ovary senescence. They effected the enlargement of mesocarp cells and the differentiation of endocarp cells in very similar patterns, suggesting a similar induction of the structural processes involved in fruit development. Ultrastructural changes in mesocarp cells after treatment with gibberellic acid showed that rapid enlargement of mesocarp cells was sustained mainly by a reorganization of the membrane systems directed to the sysnthesis of primary cell wall. Early changes in the subcellular components in mesocarp cells were observed as the first symptoms in ovary senescence. 相似文献
970.
Mercedes Giralt Teresa Gasull Joaquin Hernandez Aurora Garcia Juan Hidalgo 《Biometals》1993,6(3):171-178
Eighteen hours of immobilization stress, accompanied by food and water deprivation, increased liver metallothionein (MT) but decreased kidney MT levels. Food and water deprivation alone had a significant effect only on liver MT levels. In contrast, stress and food and water deprivation increased both liver and kidney lipid peroxidation levels, indicating that the relationship between MT and lipid peroxidation levels (an index of free radical production) is unclear. Adrenalectomy increased both liver and kidney MT levels in basal conditions, whereas the administration of corticosterone in the drinking water completely reversed the effect of adrenalectomy, indicating an inhibitory role of glucocorticoids on MT regulation in both tissues. Changes in glutathione (GSH) metabolism produced significant effects on kidney MT levels. Thus, the administration of buthionine sulfoximine, an inhibitor of GSH synthesis, decreased kidney GSH and increased kidney MT content, suggesting that increased cysteine pools because of decreased GSH synthesis might increase kidney MT levels through an undetermined mechanism as it appears to be the case in the liver. However, attempts to increase kidney MT levels by the administration of cysteine or GSH were unsuccesful, in contrast to what is known for the liver. The present results suggest that there are similarities but also substantial differences between liver and kidney MT regulation in these experimental conditions. 相似文献