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971.
Amare A Hummon AB Southey BR Zimmerman TA Rodriguez-Zas SL Sweedler JV 《Journal of proteome research》2006,5(5):1162-1167
Neuropeptides are an important class of cell to cell signaling molecules that are difficult to predict from genetic information because of their large number of post-translational modifications. The transition from prohormone genetic sequence information to the determination of the biologically active neuropeptides requires the identification of the cleaved basic sites, among the many possible cleavage sites, that exist in the prohormone. We report a binary logistic regression model trained on mammalian prohormones that is more sensitive than existing methods in predicting these processing sites, and demonstrate the application of this method to mammalian neuropeptidomic studies. By comparing the predictive abilities of a binary logistic model trained on molluscan prohormone cleavages with the reported model, we establish the need for phyla-specific models. 相似文献
972.
Luo Q Tang K Yang F Elias A Shen Y Moore RJ Zhao R Hixson KK Rossie SS Smith RD 《Journal of proteome research》2006,5(5):1091-1097
The sensitivity of proteomics measurements using liquid chromatography (LC) separations interfaced with electrospray ionization-mass spectrometry (ESI-MS) improves approximately inversely with liquid flow rate (for the columns having the same separation efficiency, linear velocity, and porosity), making attractive the use of smaller inner diameter LC columns. We report the development and initial application of 10 microm i.d. silica-based monolithic LC columns providing more sensitive proteomics measurements. A 50-microm-i.d. micro solid-phase extraction precolumn was used for ease of sample injection and cleanup prior to the reversed-phase LC separation, enabling the sample volume loading speed to be increased by approximately 50-fold. Greater than 10-fold improvement in sensitivity was obtained compared to analyses using more conventional capillary LC, enabling e.g. the identification of >5000 different peptides by MS/MS from 100-ng of a Shewanella oneidensis tryptic digest using an ion trap MS. The low nL/min LC flow rates provide more uniform responses for different peptides, and provided improved quantitative measurements compared to conventional separation systems without the use of internal standards or isotopic labeling. The improved sensitivity allowed LC-MS measurements of immunopurified protein phosphatase 5 that were in good agreement with quantitative Western blot analyses. 相似文献
973.
The catabolism of fatty acids is important in the lifestyle of many fungi, including plant and animal pathogens. This has been investigated in Aspergillus nidulans, which can grow on acetate and fatty acids as sources of carbon, resulting in the production of acetyl coenzyme A (CoA). Acetyl-CoA is metabolized via the glyoxalate bypass, located in peroxisomes, enabling gluconeogenesis. Acetate induction of enzymes specific for acetate utilization as well as glyoxalate bypass enzymes is via the Zn2-Cys6 binuclear cluster activator FacB. However, enzymes of the glyoxalate bypass as well as fatty acid beta-oxidation and peroxisomal proteins are also inducible by fatty acids. We have isolated mutants that cannot grow on fatty acids. Two of the corresponding genes, farA and farB, encode two highly conserved families of related Zn2-Cys6 binuclear proteins present in filamentous ascomycetes, including plant pathogens. A single ortholog is found in the yeasts Candida albicans, Debaryomyces hansenii, and Yarrowia lipolytica, but not in the Ashbya, Kluyveromyces, Saccharomyces lineage. Northern blot analysis has shown that deletion of the farA gene eliminates induction of a number of genes by both short- and long-chain fatty acids, while deletion of the farB gene eliminates short-chain induction. An identical core 6-bp in vitro binding site for each protein has been identified in genes encoding glyoxalate bypass, beta-oxidation, and peroxisomal functions. This sequence is overrepresented in the 5' region of genes predicted to be fatty acid induced in other filamentous ascomycetes, C. albicans, D. hansenii, and Y. lipolytica, but not in the corresponding genes in Saccharomyces cerevisiae. 相似文献
974.
Formstecher E Reverdy C Cholay M Planquette C Trouplin V Lehrmann H Aresta S Calabrese A Arar K Daviet L Colland F 《Oligonucleotides》2006,16(4):387-394
Gene silencing by RNA interference (RNAi) has proven to be a powerful tool for investigating gene function in mammalian cells. Combination of several short interfering RNA (siRNA) targeting the same gene is commonly used to improve RNA interference. However, in contrary to the well-described mechanism of RNAi, efficiency of single siRNA compared to pool remains poorly documented. We addressed this issue using several active and inactive siRNA targeting Eg5, a kinesin-related motor involved in mitotic spindle assembly. These siRNA, used alone or in combination, were tested for their silencing efficiency in several cancer cell lines. Here we show that presence of inactive Eg5 siRNA in a pool dramatically decreases knockdown efficacy in a cell line- and dose-dependent manner. Lack of inhibition by unrelated siRNA suggests that a competition may occur during siRNA incorporation into RNA-induced silencing complexes (RISCs) along with the target mRNA. Altogether, our results, which need to be confirmed with additional inactive siRNA, indicate that combination of siRNA may not increase but instead decrease silencing efficiency. 相似文献
975.
Temporomandibular disorders are a form of musculoskeletal disorders, which reduce the function of stomatognathic system and they are related to some other diseases causing painful conditions and disorders of oral function. The aim of this paper is to describe a one year follow up clinical case of a female patient with comorbid multiple sclerosis and a relatively rare form of articular disc disorder. Primary clinical diagnostics encompassed manual methods of TMJ examination. Definite diagnosis included radiologic examination. Clinical hyperextensive condyle position was palpated bilaterally and subsequently confirmed by a functional panoramic radiograph of TMJ. The anterior displacement of disc with reduction was diagnosed by magnetic resonance and in the right joint there was a disc displacement upon excursive movement. From relevant literature, the relationship of a number of diseases that can be related to functional disorder of the orofacial system, such as multiple sclerosis, has been described from many aspects. Also, apart from the standard classification of one form of anterior displacement of the disc, made primarily by magnetic resonance, cases of disc displacement upon excursive mandibular movement can rarely be found in literature. 相似文献
976.
Brncić N Mijandrusić-Sincić B Perić R Milić S Gorup L Mazur-Grbac M 《Collegium antropologicum》2010,34(Z2):267-269
Splenic rupture is rare but life threatening complication of mononucleosis syndrome. It has been suggested that subcapsular splenic hematoma formation precedes rupture. The case of 44-year-old, previously healthy, male with splenic hematoma occurring after rising of heavy cargo is reported. Mononucleosis syndrome was suggested based on routine laboratory tests (elevated white blood cell count with predominance of lymphocytes and raised serum transaminases) and CMV infection was confirmed by serological test. Nonoperative management was used since the patient was hemodynamically stable with no further signs of splenic rupture. The same approach has been used in growing number of cases of patients with spontaneous splenic rupture in mononucleosis syndrome. Importance of considering splenic hematoma and/or rupture if abdominal pain occurs in the course of mononucleosis syndrome is outlined as well as importance of routine laboratory tests in suspecting mononucleosis syndrome in otherwise clinically silent patient. 相似文献
977.
Gerlind U. C. Lehmann Sandra Berger Johannes Strauß Arne W. Lehmann Hans-Joachim Pflüger 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2010,196(11):807-816
Reduction of tympanal hearing organs is repeatedly found amongst insects and is associated with weakened selection for hearing.
There is also an associated wing reduction, since flight is no longer required to evade bats. Wing reduction may also affect
sound production. Here, the auditory system in four silent grasshopper species belonging to the Podismini is investigated.
In this group, tympanal ears occur but sound signalling does not. The tympanal organs range from fully developed to remarkably
reduced tympana. To evaluate the effects of tympanal regression on neuronal organisation and auditory sensitivity, the size
of wings and tympana, sensory thresholds and sensory central projections are compared. Reduced tympanal size correlates with
a higher auditory threshold. The threshold curves of all four species are tuned to low frequencies with a maximal sensitivity
at 3–5 kHz. Central projections of the tympanal nerve show characteristics known from fully tympanate acridid species, so
neural elements for tympanal hearing have been strongly conserved across these species. The results also confirm the correlation
between reduction in auditory sensitivity and wing reduction. It is concluded that the auditory sensitivity of all four species
may be maintained by stabilising selective forces, such as predation. 相似文献
978.
Sandra Maria Alvarenga Gomes Julio Antonio Lombardi 《Plant Systematics and Evolution》2010,289(1-2):13-33
The current classification systems recognize Salacioideae as a monophyletic group within Celastraceae. Nonetheless, some divergences exist for genera: in some cases, most species of the subfamily have been included in only two genera; in others, these genera have been subdivided. This study characterizes the leaf anatomy of 31 species of the subfamily Salacioideae as a contribution to identifying them through features that may also help distinguish among genera. Cross-sections of the median region of the leaf blade and of the petiole and dissociated and macerated epidermis were analyzed. Taxonomically relevant anatomical characters include the type of crystals in the parenchymatous tissue (monocrystals in Cheiloclinium and druses in other genera); the presence of laticifers in Cheiloclinium and Tontelea only; the variable form of the petiole vascular system among studied species; the type of stomata (cyclocytic with two concentric circles of subsidiary cells in P. dulcis; anomocytic in T. attenuata, T. fluminensis, and T. leptophylla; laterocytic in C. anomalum and C. hippocrateoides; and ciclocytic in the other species); the sinuosity of the anticlinal walls of the epidermal cells (sinuous in Cheiloclinium and Peritassa, except P. laevigata, and in S. arborea, S. insignis, S. mosenii, S. nemerosa, and S. opacifolia, and straight in all other studied species); the presence of crystalliferous idioblasts in the epidermis of P. dulcis, P. flaviflora, and P. mexiae; and the presence, form, and disposition of sclereids in the leaf blade, which is a highly variable character among the studied species. 相似文献
979.
Emanuela Signori Sandra Iurescia Emanuela Massi Daniela Fioretti Pieranna Chiarella Mariangela De Robertis Monica Rinaldi Giancarlo Tonon Vito Michele Fazio 《Cancer immunology, immunotherapy : CII》2010,59(10):1583-1591
After more than 15 years of experimentation, DNA vaccines have become a promising perspective for tumour diseases, and animal models are widely used to study the biological features of human cancer progression and to test the efficacy of vaccination protocols. In recent years, immunisation with naked plasmid DNA encoding tumour-associated antigens or tumour-specific antigens has revealed a number of advantages: antigen-specific DNA vaccination stimulates both cellular and humoral immune responses; multiple or multi-gene vectors encoding several antigens/determinants and immune-modulatory molecules can be delivered as single administration; DNA vaccination does not induce autoimmune disease in normal animals; DNA vaccines based on plasmid vectors can be produced and tested rapidly and economically. However, DNA vaccines have shown low immunogenicity when tested in human clinical trials, and compared with traditional vaccines, they induce weak immune responses. Therefore, the improvement of vaccine efficacy has become a critical goal in the development of effective DNA vaccination protocols for anti-tumour therapy. Several strategies are taken into account for improving the DNA vaccination efficacy, such as antigen optimisation, use of adjuvants and delivery systems like electroporation, co-expression of cytokines and co-stimulatory molecules in the same vector, different vaccination protocols. In this review we discuss how the combination of these approaches may contribute to the development of more effective DNA vaccination protocols for the therapy of lymphoma in a mouse model. 相似文献
980.
Sandra J. McInnes 《Polar Biology》2010,33(1):59-70
Echiniscus corrugicaudatus sp. nov., (Heterotardigrada; Echiniscidae) was found in the limited vegetation from the inland nunataks of Ellsworth Land,
West Antarctica. The tardigrade fauna of this a rarely explored region shows limited overlap with the fauna from the maritime
or coastal continental Antarctic. This species is placed within the Echiniscus “arctomys-group” based on the characteristic of, “a lack of body appendages other than cirrus A”. It has less well-defined edges to
the dorsal plates than other species within the group and distinct ridges on the caudal plate. Males were found in the population
indicating gonochoristic reproduction, and a large number of juveniles suggesting an over-wintering strategy of eggs or a
biennial population over-wintering as adults/sub-adults and eggs. 相似文献