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151.
Capsule: Taiga Bean Geese Anser fabalis fabalis wintering near Falkirk, Scotland staged in Denmark, Norway and Sweden and summered in central Sweden.

Aims: To determine the migration routes, timing of movements, breeding area and home ranges of Taiga Bean Geese wintering near Falkirk, Scotland.

Methods: Ten Taiga Bean Geese, caught on the wintering grounds in Scotland, were marked with neck collars carrying global positioning system (GPS) tags. A further 21 geese were fitted with individually marked plastic neck collars. GPS location data were collected and field counts and searches for individually marked geese were undertaken to provide detailed information on their location throughout the year.

Results: Seven GPS tags provided information away from Scotland, indicating that two migration routes were used en route to the breeding grounds in Dalarna, Sweden. During the non-breeding season, the total home range of the geese was approximately 466?km2, although the total area within agricultural fields used by the geese may have been as small as 13?km2.

Conclusions: The timing of movements, migration routes, breeding area and identification of important stop-over sites for this wintering population are described for the first time.  相似文献   

152.
True Shrikes (Laniidae) are sit-and-wait predators that hunt prey from elevated perches and frequently impale them on sharp objects in conspicuous places. During the 2014 breeding season, we followed a pair of Loggerhead Shrike (Lanius ludovicianus) through their reproductive cycle and documented over 100 h of their behavior on video. On three occasions, the shrikes were observed hunting grasshoppers and in a sequence of very quick stereotypic behaviors, they eviscerated their prey. The shrike held the grasshopper in its feet and with its sharp beak, penetrated the body between the head and the shield-like pronotum, removed the digestive tract in one pull, and then ingested the prey. The removal of the alimentary tract appears to target the anterior portion, specifically the foregut or crop, along with its associated contents. This particular behavior was observed only when grasshoppers were caught but not with other invertebrates. The whole process lasted ca. 5 (±2.6 SD) s.  相似文献   
153.
154.
North American glyptodonts originated from South American ancestors during the Great American Biotic Interchange no later than early Blancan North American Land Mammal Age (NALMA). A substantial expansion in population samples from the late Blancan 111 Ranch fauna of southeastern Arizona, several late Blancan faunas in New Mexico, and the early Blancan–Irvingtonian faunas of Guanajuato, Mexico, permit, analysis of sexual dimorphism and ontogeny of Glyptotherium texanum Osborn, 1903. Growth of carapacial osteoderms was allometric, including changes of the external sculpturing. Overall anatomy of the carapace changed with growth, with development of distinctive pre-iliac and post-iliac regions in lateral profile of adults. Skulls of adults possess a unique boss on the anterior surface of the descending process of the zygomatic arch that is not present in juveniles. Sexual dimorphism involves differences in anatomy of lateral and posterior osteoderms. Glyptotherium arizonae Gidley, 1926, is a junior synonym of G. texanum. The temporal distribution of G. texanum extends from early Blancan NALMA to Irvingtonian NALMA, with geographical distribution from Central America and Mexico to southern United States.  相似文献   
155.
Conversion of CO2 to energy‐rich chemicals using renewable energy is of much interest to close the anthropogenic carbon cycle. However, the current photoelectrochemical systems are still far from being practically feasible. Here the successful demonstration of a continuous, energy efficient, and scalable solar‐driven CO2 reduction process based on earth‐abundant molybdenum disulfide (MoS2) catalyst, which works in synergy with an inexpensive hybrid electrolyte of choline chloride (a common food additive for livestock) and potassium hydroxide (KOH) is reported. The CO2 saturated hybrid electrolyte utilized in this study also acts as a buffer solution (pH ≈ 7.6) to adjust pH during the reactions. This study reveals that this system can efficiently convert CO2 to CO with solar‐to‐fuel and catalytic conversion efficiencies of 23% and 83%, respectively. Using density functional theory calculations, a new reaction mechanism in which the water molecules near the MoS2 cathode act as proton donors to facilitate the CO2 reduction process by MoS2 catalyst is proposed. This demonstration of a continuous, cost‐effective, and energy efficient solar driven CO2 conversion process is a key step toward the industrialization of this technology.  相似文献   
156.
Protein posttranslational modifications critically regulate a range of physiological and disease processes. In addition to tyrosine, serine, and threonine phosphorylation, reversible N‐ε acylation and alkylation of protein lysine residues also modulate diverse aspects of cellular function. Studies of lysine acyl and alkyl modifications have focused on nuclear proteins in epigenetic regulation; however, lysine modifications are also prevalent on cytosolic proteins to serve increasingly apparent, although less understood roles in cell regulation. Here, the methyl‐lysine (meK) proteome of anucleate blood platelets is characterized. With high‐resolution, multiplex MS methods, 190 mono‐, di‐, and tri‐meK modifications are identified on 150 different platelet proteins—including 28 meK modifications quantified by tandem mass tag (TMT) labeling. In addition to identifying meK modifications on calmodulin (CaM), GRP78 (HSPA5, BiP), and EF1A1 that have been previously characterized in other cell types, more novel modifications are also uncovered on cofilin, drebin‐like protein (DBNL, Hip‐55), DOCK8, TRIM25, and numerous other cytoplasmic proteins. Together, the results and analyses support roles for lysine methylation in mediating cytoskeletal, translational, secretory, and other cellular processes. MS data for this study have been deposited into the ProteomeXchange Consortium via the PRIDE partner repository with the dataset identifier PXD012217.  相似文献   
157.
158.
Migratory waterfowl of the world are the natural reservoirs of influenza viruses of all known subtypes. However, it is unknown whether these waterfowl perpetuate highly pathogenic (HP) H5 and H7 avian influenza viruses. Here we report influenza virus surveillance from 2001 to 2006 in wild ducks in Alberta, Canada, and in shorebirds and gulls at Delaware Bay (New Jersey), United States, and examine the frequency of exchange of influenza viruses between the Eurasian and American virus clades, or superfamilies. Influenza viruses belonging to each of the subtypes H1 through H13 and N1 through N9 were detected in these waterfowl, but H14 and H15 were not found. Viruses of the HP Asian H5N1 subtypes were not detected, and serologic studies in adult mallard ducks provided no evidence of their circulation. The recently described H16 subtype of influenza viruses was detected in American shorebirds and gulls but not in ducks. We also found an unusual cluster of H7N3 influenza viruses in shorebirds and gulls that was able to replicate well in chickens and kill chicken embryos. Genetic analysis of 6,767 avian influenza gene segments and 248 complete avian influenza viruses supported the notion that the exchange of entire influenza viruses between the Eurasian and American clades does not occur frequently. Overall, the available evidence does not support the perpetuation of HP H5N1 influenza in migratory birds and suggests that the introduction of HP Asian H5N1 to the Americas by migratory birds is likely to be a rare event.  相似文献   
159.
Identifying deamidated peptides using low-resolution mass spectrometry is difficult because traditional database search programs cannot accurately detect modified peptides when the mass differences are only 0.984 Da. In this study, we utilized differential reversed-phase elution behavior of deamidated and corresponding unmodified peptide forms to significantly improve deamidation detection on a low-resolution LCQ ion trap instrument. We also improved the mass measurements of unmodified and deamidated peptide forms by averaging survey scans across each chromatogram peak. Tryptic digests of a series of normal (3-day old, 2-year old, 18-year old, 35-year old, and 70-year old) and cataractous (93-year old) human lens samples were used to produce large numbers of potentially deamidated peptides. The complex peptide mixtures were separated by strong cation exchange (SCX) chromatography followed by reversed-phase (RP) chromatography. Synthetic peptides were used to show that unmodified and deamidated peptides coeluted during the SCX separation and were completely resolved with the RP conditions used. Retention time shifts (RTS) and mass differences (DeltaM) of deamidated lens peptides and their corresponding unmodified forms were manually determined for the 70-year old lens sample. These values were used to assign correct or incorrect deamidation identifications from SEQUEST searches where deamidation was specified as a variable modification. Manual validation of SEQUEST identifications from synthetic peptides, 3-day old, and 70-year old samples had an overall 42% deamidation detection accuracy. Filtering SEQUEST identifications using RTS and DeltaM constraints resulted in >93% deamidation detection accuracy. An algorithm was developed to automate this method, and 72 Crystallin deamidation sites, 18 of which were not previously reported in human lens tissue, were detected.  相似文献   
160.
Current theories agree that there appears to be no unique feature responsible for the remarkable heat stability properties of hyperthermostable proteins. A concerted action of structural, dynamic and other physicochemical attributes are utilized to ensure the delicate balance between stability and functionality of proteins at high temperatures. We have thoroughly screened the literature for hyperthermostable enzymes with optimal temperatures exceeding 100 degrees C that can potentially be employed in multiple biotechnological and industrial applications and to substitute traditionally used, high-cost engineered mesophilic/thermophilic enzymes that operate at lower temperatures. Furthermore, we discuss general methods of enzyme immobilization and suggest specific strategies to improve thermal stability, activity and durability of hyperthermophilic enzymes.  相似文献   
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