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991.
Dolors Vidal Ibone Anza Mark A. Taggart Elisa Pérez-Ramírez Elena Crespo Ursula Hofle Rafael Mateo 《Applied and environmental microbiology》2013,79(14):4264-4271
Between 1978 and 2008, 13 avian botulism outbreaks were recorded in the wetlands of Mancha Húmeda (central Spain). These outbreaks caused the deaths of around 20,000 birds from over 50 species, including globally endangered white-headed ducks (Oxyura leucoceophala). Here, a significant association was found between the number of dead birds recorded in each botulism outbreak and the mean temperature in July (always >26°C). The presence of Clostridium botulinum type C/D in wetland sediments was detected by real-time PCR (quantitative PCR [qPCR]) in 5.8% of 207 samples collected between 2005 and 2008. Low concentrations of Cl− and high organic matter content in sediments were significantly associated with the presence of C. botulinum. Seventy-five digestive tracts of birds found dead during botulism outbreaks were analyzed; C. botulinum was present in 38.7% of them. The prevalence of C. botulinum was 18.2% (n = 22 pools) in aquatic invertebrates (Chironomidae and Corixidae families) and 33.3% (n = 18 pools) in necrophagous invertebrates (Sarcophagidae and Calliphoridae families), including two pools of adult necrophagous flies collected around bird carcasses. The presence of the bacteria in the adult fly form opens up new perspectives in the epidemiology of avian botulism, since these flies may be transporting C. botulinum from one carcass to another. 相似文献
992.
Constanza Giselle Taverna María Eugenia Bosco-Borgeat Omar Alejandro Murisengo Graciela Davel Mariana C?rtes Boité Elisa Cupolillo Cristina Elena Canteros 《Memórias do Instituto Oswaldo Cruz》2013,108(2):178-185
As the distribution of Candida species and their susceptibility to antifungal agents have changed, a new means of accurately and rapidly identifying these species is necessary for the successful early resolution of infection and the subsequent reduction of morbidity and mortality. The current work aimed to evaluate ribosomal RNA gene sequencing for the identification of medically relevant Candida species in comparison with a standard phenotypic method. Eighteen reference strains (RSs), 69 phenotypically identified isolates and 20 inconclusively identified isolates were examined. Internal transcribed spaces (ITSs) and D1/D2 of the 26S ribosomal RNA gene regions were used as targets for sequencing. Additionally, the sequences of the ITS regions were used to establish evolutionary relationships. The sequencing of the ITS regions was successful for 88% (94/107) of the RS and isolates, whereas 100% of the remaining 12% (13/107) of the samples were successfully analysed by sequencing the D1/D2 region. Similarly, genotypic analysis identified all of the RS and isolates, including the 20 isolates that were not phenotypically identified. Phenotypic analysis, however, misidentified 10% (7/69) of the isolates. Phylogenetic analysis allowed the confirmation of the relationships between evolutionarily close species. Currently, the use of genotypic methods is necessary for the correct identification of Candida species. 相似文献
993.
Ligia Cristina Kalb Souza Rosana Elisa Gon?alves Gon?alves Pinho Carla Vanessa de Paula Lima Stênio Perdig?o Fragoso Maurilio José Soares 《Memórias do Instituto Oswaldo Cruz》2013,108(5):631-636
Heteroxenic and monoxenic trypanosomatids were screened for the
presence of actin using a mouse polyclonal antibody produced against the entire
sequence of the Trypanosoma cruzi actin gene, encoding a 41.9
kDa protein. Western blot analysis showed that this antibody reacted with a
polypeptide of approximately 42 kDa in the whole-cell lysates of parasites
targeting mammals (T. cruzi, Trypanosoma
brucei and Leishmania major), insects
(Angomonas deanei, Crithidia fasciculata,
Herpetomonas samuelpessoai and Strigomonas
culicis) and plants (Phytomonas serpens). A single
polypeptide of approximately 42 kDa was detected in the whole-cell lysates of
T. cruzi cultured epimastigotes, metacyclic trypomastigotes
and amastigotes at similar protein expression levels. Confocal microscopy showed
that actin was expressed throughout the cytoplasm of all the tested
trypanosomatids. These data demonstrate that actin expression is widespread in
trypanosomatids. 相似文献
994.
Paolo Paoli Elisa Giannoni Paola Chiarugi 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》2013,1833(12):3481-3498
Anoikis is a programmed cell death induced upon cell detachment from extracellular matrix, behaving as a critical mechanism in preventing adherent-independent cell growth and attachment to an inappropriate matrix, thus avoiding colonizing of distant organs. As anchorage-independent growth and epithelial–mesenchymal transition, two features associated with anoikis resistance, are vital steps during cancer progression and metastatic colonization, the ability of cancer cells to resist anoikis has now attracted main attention from the scientific community. Cancer cells develop anoikis resistance due to several mechanisms, including change in integrins' repertoire allowing them to grow in different niches, activation of a plethora of inside-out pro-survival signals as over-activation of receptors due to sustained autocrine loops, oncogene activation, growth factor receptor overexpression, or mutation/upregulation of key enzymes involved in integrin or growth factor receptor signaling. In addition, tumor microenvironment has also been acknowledged to contribute to anoikis resistance of bystander cancer cells, by modulating matrix stiffness, enhancing oxidative stress, producing pro-survival soluble factors, triggering epithelial–mesenchymal transition and self-renewal ability, as well as leading to metabolic deregulations of cancer cells. All these events help cancer cells to inhibit the apoptosis machinery and sustain pro-survival signals after detachment, counteracting anoikis and constituting promising targets for anti-metastatic pharmacological therapy. This article is part of a Special Section entitled: Cell Death Pathways. Guest Editors: Frank Madeo and Slaven Stekovic. 相似文献
995.
Metrichia cuniapiru, sp. n. (tribe Ochrotrichiini, family Hydroptilidae) from Misiones Province is described. Main characters useful for recognition of females of different species of Metrichia and keys for the males and larvae are provided. The pupa of M. neotropicalis is also described. 相似文献
996.
Marisol López Pedro Dorado Alberto Ortega Eva Peñas-Lledó Nancy Monroy Irma Silva-Zolezzi Jesús Cobaleda Alicia Gallego-Aguilera María Elisa Alonso Adrián LLerena 《Molecular biology reports》2013,40(4):3187-3192
UDP-glucuronosyltransferase 1A4 (UGT1A4) is a phase II drug-metabolizing enzyme that catalyzes the glucuronidation of many clinically-important drugs. Interethnic differences in the genetic polymorphism of UGT1A4 have been reported; however, there is no information in Mexican Mestizos (MMs) and Spaniards (SPs). Furthermore, MM is an admixed population with 26 % of Caucasian genes mainly from Spain. Therefore, this study aimed to investigate the potential differences between 318 SPs and 248 MMs healthy individuals regarding UGT1A4*1b, UGT1A4*2 and UGT1A4*3 alleles and to compare the observed frequencies with those previously reported in different populations. The allelic frequencies of the three UGT1A4 polymorphisms showed interethnic differences between MMs and SPs (p < 0.05). The analyzed SNPs variants in this genetic region were not in linkage disequilibrium (LD) for the MM population, suggesting that these mutations have arisen independently in the same genetic background. In contrast, UGT1A4*2 and UGT1A4*3 were in LD in the SP population. Comparison of present data with other in different ethnic groups revealed that the frequencies of UGT1A4*2 and UGT1A4*3 in SP were similar to other Caucasians and higher than in Asians, whereas in MMs were lower than in Caucasians and higher than in Asians only for UGT1A4*2. Present results could be helpful to improve the use of UGT1A4 drug substrates in order to adjust them to the ethnic background of a given population, specifically for Hispanics. 相似文献
997.
Luca Bartolini Stefano Sartori Elisabetta Lenzini Chiara Rigon Elisa Cainelli Cristina Agrati Irene Toldo Marta Donà Eva Trevisson 《Gene》2013
We report on a boy with speech delay, mental retardation, motor clumsiness, hyperactivity, dysmorphic facial features, brachytelephalangy and short stature. Electrocardiogram, echocardiography, renal ultrasound, electroencephalogram, fundoscopic exam and auditory brainstem responses were all normal. Brain magnetic resonance imaging showed a left temporal arachnoid cyst and a small pineal gland cyst. 相似文献
998.
Laia Rodriguez-Revenga Irene Madrigal Josep Blanch-Rubió Dei M. Elurbe Elisa Docampo Antonio Collado Javier Vidal Jordi Carbonell Xavier Estivill Montserrat Mila 《Gene》2013
Fibromyalgia is a chronic condition characterized by widespread pain, fatigue, non-restorative sleep and cognitive difficulties that affects 2–4% of the general population. Recently a possible relationship between the FMR1 premutation and fibromyalgia has been pointed out. In attempt to gather more data we screened for the FMR1 CGG expansion 700 DNA samples from unrelated fibromyalgia patients. This data might be useful for evaluating the incorporation of this test in rheumatologic procedures for women with fibromyalgia. The observed frequency of FMR1 premutation carriers (3 of 700, 0.4%) is not significantly different from the estimated rate in the general female population (1/250–1/400) (P = 0.539, P = 0.716). Clinical examination of the FMR1 premutation carriers identified revealed that all of them had important neurological symptoms with regard to muscular symptoms, neurocognitive alterations and neurovegetative impairments. With regard to other clinical aspects of the disease the cases apparently did not differ from the average fibromyalgia patients. On the basis of our results an FMR1 screening among fibromyalgia female patients would not be recommended. However it would be worthwhile to further evaluate the different clinical presentations that fibromyalgia patients might present based on their FMR1 premutation carrier status. 相似文献
999.
Anna Vidus-Rosin Alberto Meriggi Elisa Cardarelli Sara Serrano-Perez Maria-Chiara Mariani Chiara Corradelli Annalisa Barba 《Acta theriologica》2011,56(1):53-61
In northern Italy, the range of the Eastern cottontail (Sylvilagus floridanus) largely overlaps with that of the native European hare (Lepus europaeus) on the Po Plain. Both species appear to have similar habitat requirements. We studied habitat selection by hares and cottontails
during feeding activity from September 2006 to August 2007 in two areas where they occur alone (allopatry) and in one area
where they occur together (sympatry). The three areas were basically similar, so that shifts in habitat use observed in sympatry
should reflect the response to interspecific competition. Habitat selection was examined at micro- and macro-habitat levels
throughout seasons. Habitat breadth of both species followed the change of resource availability through seasons in allopatry
as well as in sympatry. No shifts in habitat use were evident at macro-habitat level, even during autumn which was the limiting
season. Exploitation of shared habitats by the two species seems to be promoted by differential micro-habitat use within macro-habitat
types. Cottontails used woods with dense understory in greater proportion than hares, and their present sites were concentrated
within the maximum distance of 20 m of the nearest shelter site. Hares were more likely than cottontails to exploit crops,
and their sites were distributed even greater than 80 m away from permanent cover patches. The habitat heterogeneity of agricultural
ecosystems within the sympatry range could buffer the negative effects of external factors (climate, human disturbance and
predation) on hares, and enhance the chances of exploitation of shared habitats by both species. 相似文献
1000.
Venturi E Mio K Nishi M Ogura T Moriya T Pitt SJ Okuda K Kakizawa S Sitsapesan R Sato C Takeshima H 《Biochemistry》2011,50(13):2623-2632
Mitsugumin 23 (MG23) is a 23 kDa transmembrane protein localized to the sarcoplasmic/endoplasmic reticulum and nuclear membranes in a wide variety of cells. Although the characteristics imply the participation in a fundamental function in intracellular membrane systems, the physiological role of MG23 is unknown. Here we report the biochemical and biophysical characterization of MG23. Hydropathicity profile and limited proteolytic analysis proposed three transmembrane segments in the MG23 primary structure. Chemical cross-linking analysis suggested a homo-oligomeric assembly of MG23. Ultrastructural observations detected a large symmetrical particle as the predominant component and a small asymmetric assembly as the second major component in highly purified MG23 preparations. Single-particle three-dimensional reconstruction revealed that MG23 forms a large bowl-shaped complex equipped with a putative central pore, which is considered an assembly of the small asymmetric subunit. After reconstitution into planar phospholipid bilayers, purified MG23 behaved as a voltage-dependent, cation-conducting channel, permeable to both K(+) and Ca(2+). A feature of MG23 gating was that multiple channels always appeared to be gating together in the bilayer. Our observations suggest that the bowl-shaped MG23 can transiently assemble and disassemble. These building transitions may underlie the unusual channel gating behavior of MG23 and allow rapid cationic flux across intracellular membrane systems. 相似文献