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781.
Summary The blood supply of duck muscle spindles from the extensor pollicis and the extensor digitorum comminis wing muscles has been studied by light and electron microscopy. Capillaries usually accompany the nerve bundle that innervates the spindle, approaching at an oblique angle around the midequatorial region. Capillaries may run for some distance along the surface of the outer capsule, or penetrate partially into the outer capsule and lie between layers of the capsule cell processes. Some capillaries also penetrate the outer capsule, running into the periaxial space and continuing further towards the polar region. They have been shown to be in close contact with intrafusal muscle fibres, from the juxta-equatorial to the polar region, but have not been encountered among sensory terminals in the mid-equatorial region.  相似文献   
782.
During the UK Natural Environment Research Council (NERC) NorthSea Community Programme 1987–1992, pelagic flagellatepopulations in the southern North Sea were examined during theperiod 1988–89. Not less than 84 species of flagellateswere found, of which 73 could be identified down to genus orspecies level using light or scanning electron microscopy: 52dinoflagel lates, six cryptomonads, five green flagellates,four prymnesiomonads, two chrysomonads, one euglenid, one silicoflagellate,one bodonid and one flagellate incertae sedis. In addition,there were not less than six unidentified species of flagellatesincertae sedis, two small (<15 µm) unidentified nakeddinoflagellates, one unidentified cryptomonad, one unidentifiedcoccolithophorid, and unspecified numbers of unidentified speciesof choanoflagellates. There were 44 phototrophs (of which eightwere mixotrophic or possibly so), 35 heterotrophs, and fiveflagellates whose mode of nutrition is unknown. A total of 12flagellates were found in all of the areas investigated, whileanother nine were found in one area only. Areas 9 (German coastalwater near Helgoland) and 1 (Anglian coastal mixed water) werethe most and least species rich, respectively. Observationson size-diversity relationships suggested that the highest diversityof flagellates occurred close to the lower limits of the sizeranges. Some interesting or rarely reported flagellates aredescribed.  相似文献   
783.
The low heat resistance (D100 = 0.554 min, z = 13.4 degrees C) of dormant lysozyme-sensitized spores of Bacillus sphaericus 9602 was correlated with a low protoplast wet density (1.305 g/ml) equivalent to a high protoplast water content (61.0%, wet weight basis). These values for these unusual spores were consistent with those correlated previously in 28 spore types of seven other species.  相似文献   
784.
785.
Synthesis is described for the N-o-nitrophenylsulfenylheptapeptide tert-butoxycarbonylhydrazide corresponding to positions 17–23 of the amino acid sequence of baker's yeast iso-1-cytochrome c. Moreover a new method of selective removal of the S-acetamidomethyl group for analytical and preparative purpose is reported.  相似文献   
786.
The present paper reports the results of a bacteriological and mycological monitoring carried out on the airborne microflora of the Sistine Chapel. The general aim of the study was to evaluate the impact of the flow of visitors, as well seasonal effects, on the qualitative and quantitative variations of microorganisms. Two sampling campaigns were carried out in May and November 1997. A Surface Air System (SAS) sampler (active system) and a sedimentation based sampler (passive system), supported by an original plinth, were used. Temperature, humidity and carbon dioxide were detected. VITEK SYSTEMS jr. for Staphylococcus spp. and microscopic observation for microfungi were the identification methods. In spite of the conditioning and filtration air system, initial results with both samplers, show a positive correlation between the airborne microorganisms and presence and number of visitors. The SAS samples showed higher microbial load, for both bacteria and fungi, than the passive ones, but the epidemiological meaning of the differently collected data varies. The increase during visiting hours of human Staphylococcus spp. is stronger than the airborne bacterial load increase. The microfungi most frequently isolated were Cladosporium spp. and Penicillium spp. These preliminary data underline the significance of the survey for the protection of such a precious environment, and encourage the Authors to continue the ongoing monitoring. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
787.
The general strategy for the synthesis by conventional procedure of N- and C-terminal fragments and of the entire sequence of baker's yeast iso-1-cytochrome c is discussed. The synthesis of the N-benzyloxycarbonylhexadecapeptide tert-butoxycarbonylhydrazide corresponding to the sequence 1–16 of the apoprotein is described in detail.  相似文献   
788.
Five Italian families with recurrence of cases of Charcot-Marie-Tooth disease (type Ia) were analysed using three closely linked DNA probes that detect polymorphisms in the region 17p11.2. The probe pVAW409R3 detected the presence of a duplication in all the affected subjects, but not in the subjects with normal electromyographic (EMG) findings. This observation confirms previous data indicating the association of the duplication with the disease, suggesting that, at least in populations of European origin, the duplication might be the molecular feature diagnostic of the pathological trait.  相似文献   
789.
Clinical and cytogenetic data of two related patients, both trisomic for the segment 4q27 to qter, are reported. Familial studies determined that the mothers of the two probands were carriers of the same balanced translocation between chromosomes 4 and 18. Altogether, two partial trisomies 4q, five balanced karyotypes, and one 45,X0 karyotype were found in the family. The 18 cases reported to date are reviewed with respect to the karyotype-phenotype correlation.  相似文献   
790.
The European grapevine moth Lobesia botrana Denis & Schiffermüller (Lepidoptera: Tortricidae) is a major pest on grapes worldwide. Attempts to develop control methods for this pest based on grape kairomones demonstrate limited success and studies indicate that a major limiting factor is overlap between synthetic kairomones and background odours in the vineyard. Behaviourally active compounds from non‐host plants may thus represent an effective alternative for monitoring and control methods. Extracts from food plants (i.e. from capsicum, garlic and peppermint, which elicit the so‐called somatosensory sensation) are traditionally used in agriculture for the control of pest insects. Among those plants, Perilla frutescens L. (Lamiales: Lamiaceae), native of Asia, contains compounds activating sensory ion channels in mammals, which are known to be involved in the perception of somatosensory compounds and are expressed in tortricid moth antennae. In the present study, in search of non‐host volatiles with potential application in pest control, essential oil metabolites isolated from P. frutescens are screened for biological activity on the olfactory system of L. botrana. The compounds (S)‐(?)‐perillaldehyde and isoegomaketone, which are released from different P. frutescens varieties, are identified by gas chromatography‐coupled electroantennographic detection. In a dual‐choice oviposition test, females show a preference for a combination of host odours and perillaldehyde, preferring this over a host‐plant odour bouquet alone. In Y‐tube olfactometer assays, virgin males show a higher level of activity in the presence of isoegomaketone, even if not significantly responsive to the compound.  相似文献   
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