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1.
The Department of Invertebrate Zoology at the SantaBarbara Museum of Natural History houses a smallcollection of nemerteans from the Eastern PacificOcean. At present the collection containsapproximately 2000 specimen lots stored in alcohol. The historically important elements of the collectionwere obtained in transfers from the Allan HancockFoundation of the University of Southern California,the Kerkoff Marine Laboratory of the CaliforniaInstitute of Technology, and the Benthic InvertebrateMuseum of Scripps Institution of Oceanography. Thespecimens in these three collections voucher manyof the species treated in Wesley R. Coe's 1940revision of the nemerteans of the west coast of theAmericas. Type specimens were located for 4 of the 5new species group taxa and for 1 new subspecies grouptaxon erected in that publication. The Allan HancockFoundation material utilized by Coe was collected inthe 1930's during Pacific expeditions of the R/V Velero III. The material assembled by George andNettie MacGinitie at the Kerkoff lab contained anumber of specimens collected during the same timeperiod. The specimens from Coe's material at ScrippsInstitution of Oceanography were collected by TheodoreBullock and students in central California in 1939.  相似文献   
2.
A cross-linking reagent with individually controllable functional groups, N-bromoacetyl-p-azido-l-phenylalanine methyl ester, has been developed. When reacted with endoplasmic reticulum membranes stripped of their ribosomes, the bromoacetyl group is most active at basic pH, reacts only with protein, and has biphasic reaction kinetics. Although the azido function also has biphasic reaction kinetics, the extent of the irradiated reaction is different from that of the dark reaction. In addition, the azido function reacts both with protein and with RNA. In a cross-linking experiment, no cross-linking occurred until the reagent-membrane complex was irradiated, even though the complex underwent limited exposure to light. Upon irradiation, extensive cross-linking occurred.  相似文献   
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Cryptic species are common in the ocean, particularly among marine invertebrates such as octopuses. Delineating cryptic species is particularly problematic in octopus taxonomy where the plasticity recorded among taxonomic characters often results in low resolution at the species level. This study investigated the morphological relationships among seven phylogenetic clades (identified using cytochrome c oxidase subunit I) of the broadly distributed Octopus vulgaris species complex and close relatives. Morphological analyses in this study were successful in delimiting O. sinensis, Brazilian Ovulgaris and O. vulgaris sensu stricto, which was congruent with the molecular findings of this study. Analyses based on male morphology were successful in distinguishing 14 of 15 total pairwise comparisons and proved to be a more reliable indicator of species‐level relationships in comparison with female morphology. The majority of characters with the greatest discriminatory power were male sexual traits. Significant morphological differences were also recorded among sampling localities of conspecifics, with phenotype showing correlation with local environmental data. The findings of this study support the hypothesis that multiple O. vulgaris‐like species are currently being incorrectly treated under a single species name, O. vulgaris. Octopuses being exported globally under the name O. vulgaris are of extremely high fisheries market value and profile. Our findings have potentially significant implications for the naming and conservation of commercially harvested members of this species complex throughout their ranges.  相似文献   
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Two different U and S4-U containing polymers with U:s4U ratio of 3:1 and 5:1 were synthesized. Their activity as messenger RNA was studied in an amino acid incorporation cell-free system from rat liver. It was shown that both copolymers can stimulate the incorporation of phenylalanine into oligophynylalamyl-tRNA.  相似文献   
8.
Phosphorylation of the mitogen‐activated protein kinase (MAPK) is essential for its enzymatic activity and ability to control multiple substrates inside a cell. According to the current models, control of MAPK phosphorylation is independent of its substrates, which are viewed as mere sensors of MAPK activity. Contrary to this modular view of MAPK signaling, our studies in the Drosophila embryo demonstrate that substrates can regulate the level of MAPK phosphorylation in vivo. We demonstrate that a twofold change in the gene dosage of a single substrate can induce a significant change in the phosphorylation level of MAPK and in the conversion of other substrates. Our results support a model where substrates of MAPK counteract its dephosphorylation by phosphatases. Substrate‐dependent control of MAPK phosphorylation is a manifestation of a more general retroactive effect that should be intrinsic to all networks with covalent modification cycles.  相似文献   
9.
Multiple malignancies may occur in the same patient, and a few reports describe cases with multiple hematologic and non-hematologic neoplasms. We report the case of a patient who showed the sequential occurrence of four different lymphoid neoplasms together with a squamous cell carcinoma of the lung. A 62-year-old man with adenopathy was admitted to the hospital, and lymph node biopsy was positive for low-grade follicular lymphoma. He achieved a partial remission with chemotherapy. Two years later, a PET-CT scan showed a left hilar mass in the lung; biopsy showed a squamous cell carcinoma. Simultaneously, he was diagnosed with diffuse large B cell lymphoma in a neck lymph node; after chemo- and radiotherapy, he achieved a complete response. A restaging PET-CT scan 2 years later revealed a retroperitoneal nodule, and biopsy again showed a low-grade follicular lymphoma, while a biopsy of a cutaneous scalp lesion showed a CD30-positive peripheral T cell lymphoma. After some months, a liver biopsy and a right cervical lymph node biopsy showed a CD30-positive peripheral T cell lymphoma consistent with anaplastic lymphoma kinase-negative anaplastic large cell lymphoma. Flow cytometry and cytogenetic and molecular genetic analysis performed at diagnosis and during the patient’s follow-up confirmed the presence of two clonally distinct B cell lymphomas, while the two T cell neoplasms were confirmed to be clonally related. We discuss the relationship between multiple neoplasms occurring in the same patient and the various possible risk factors involved in their development.  相似文献   
10.

Background  

The broad range in growth observed in response to growth hormone (GH) treatment is mainly caused by individual variations in both GH secretion and GH sensitivity. Individual GH responsiveness can be estimated using evidence-based models that predict the response to GH treatment; however, these models can be improved. High-throughput proteomics techniques can be used to identify proteins that may potentially be used as variables in such models in order to improve their predictive ability. Previously we have reported that proteomic analyses can identify biomarkers that discriminate between short prepubertal children with idiopathic short stature (ISS) who show good or poor growth in response to GH treatment. In this study we used a pharmaco-proteomic approach to identify novel factors that correlate with the growth response to GH treatment in prepubertal children who are short due to GH deficiency or ISS. The study included 128 short prepubertal children receiving GH treatment, of whom 39 were GH-deficient and 89 had ISS. Serum protein expression profiles at study start and after 1 year of GH treatment were analyzed using SELDI-TOF. Cross-validated regression and random permutation analyses were performed to identify significant correlations between protein expression patterns and the 2-year growth response to GH treatment.  相似文献   
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