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991.
Thayana Conceição Barbosa Bruno Almeida Lopes Caroline Barbieri Blunck Marcela Braga Mansur Adriana Vanessa Santini Deyl Mariana Emerenciano Maria S. Pombo-de-Oliveira 《BMC medical genomics》2018,11(1):122
Background
Chromosome translocations are a hallmark of B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Additional genomic aberrations are also crucial in both BCP-ALL leukemogenesis and treatment management. Herein, we report the phenotypic and molecular cytogenetic characterization of an extremely rare case of BCP-ALL harboring two concomitant leukemia-associated chromosome translocations: t(1;19)(q23;q13.3) and t(9;17)(p13;q11.2). Of note, we described a new rearrangement between exon 6 of PAX5 and a 17q11.2 region, where intron 3 of SPECC1 is located. This rearrangement seems to disrupt PAX5 similarly to a PAX5 deletion. Furthermore, a distinct karyotype between diagnosis and relapse samples was observed, disclosing a complex clonal evolution during leukemia progression.Case presentation
A 16-year-old boy was admitted febrile with abdominal and joint pain. At clinical investigation, he presented with anemia, splenomegaly, low white blood cell count and 92% lymphoblast. He was diagnosed with pre-B ALL and treated according to high risk GBTLI-ALL2009. Twelve months after complete remission, he developed a relapse in consequence of a high central nervous system and bone marrow infiltration, and unfortunately died.Conclusions
To our knowledge, this is the first report of a rearrangement between PAX5 and SPECC1. The presence of TCF3-PBX1 and PAX5-rearrangement at diagnosis and relapse indicates that both might have participated in the malignant transformation disease maintenance and dismal outcome.992.
Martin Breitbach Kenichi Kimura Tiago C. Luis Christopher J. Fuegemann Petter S. Woll Michael Hesse Raffaella Facchini Sarah Rieck Katarzyna Jobin Julia Reinhardt Osamu Ohneda Daniela Wenzel Caroline Geisen Christian Kurts Wolfgang Kastenmüller Michael Hölzel Sten E.W. Jacobsen Bernd K. Fleischmann 《Cell Stem Cell》2018,22(2):262-276.e7
993.
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995.
Influence of differently managed bush‐encroached sites on the large herbivore distribution in the Namibian Savannah
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Bush encroachment is reported from savannah regions worldwide. Different management strategies are used to rehabilitate these areas. In this context, the mutual interaction between vegetation and large herbivore's distribution is evident. We studied effects of land management on vegetation structure in regard to encroaching species and the subsequent habitat use of two grazing (oryx, Oryx gazella L.; common warthog, Phacochoerus africanusGmelin ) and one browsing (greater kudu, Tragelaphus strepsicerosPallas ) herbivore species. We assumed that (i) cleared areas will be favoured by grazers and (ii) noncleared areas will be favoured by browsers. Specifically, we asked: Which factors determine the habitat use of these different feeding guilds? Consistently with our expectations, we found that warthog favoured sites with high grass cover. For oryx, surprisingly shrubs with a height of 80–150 cm influenced their distribution positively, whereas for kudu, only the interaction of site and grass cover was significant in our models. However, this was related to the occurrence of shrubs of 80–150 cm height. We conclude that the management of encroachers, resulting in differences in vegetation, did not influence herbivore distribution as expected. Other factors like human impact and vegetation cover among others are discussed as additional drivers of habitat use. 相似文献
996.
Marie Desgeorges André Mégarbané Caroline Guittard Soukeyna Carles Jacques Loiselet Jacques Demaille M. Claustres 《Human genetics》1997,100(2):279-283
Cystic fibrosis (CF) is thought to be rare among the Arab populations from the Middle East and little data have been reported
so far. We have studied a sample of 20 families living in Lebanon for several generations and who have at least one child
with CF. These families are mainly from the Maronite, Greek Catholic, Greek Orthodox, Shiite or Sunnite groups. We found a
50% rate of consanguineous marriage, independent of the community of origin. The distribution of CF genotypes was determined
through the screening of all exons of the CFTR (cystic fibrosis transmembrane conductance regulator) gene by the technique
of denaturing gradient gel electrophoresis combined with asymmetric amplification DNA sequencing. A total of ten different
mutations accounting for 87.5% of 32 unrelated CF alleles was identified, including two novel putative mutations (E672del
and IVS21-28G→A). Three mutations, ΔF508 (37.5%), W1282X (15.6%), and N1303K (9.4%) accounted for 62.5% of CF alleles. Interestingly,
in the Maronite group, 66.7% of the ΔF508 chromosomes were found to be associated with allele 7 of the IVS8(T)tract, contrasting
with the absolute linkage disequilibrium between European ΔF508 chromosomes and allele 9. During this study, two previously
undescribed polymorphisms (IVS14a + 17del5 and 2691T/C) were also identified.
Received: 2 January 1997 / Accepted: 16 March 1997 相似文献
997.
Production of ROL gene transformed plants of Rosa hybrida L. and characterization of their rooting ability 总被引:11,自引:0,他引:11
van der Salm Theo P.M. van der Toorn Caroline J.G. Bouwer Reinoud Hänisch ten Cate Charlotte H. Dons Hans J.M. 《Molecular breeding : new strategies in plant improvement》1997,3(1):39-47
Transgenic plants of the rootstock Rosa hybrida L. cv. Moneyway were produced via a two-step procedure. First, kanamycin-resistant roots were generated on stem slices from micropropagated shoots, which were cocultivated with Agrobacterium tumefaciens containing the neomycin phosphotransferase II (NPTII) gene for conferring kanamycin resistance, together with individual ROL genes from A. rhizogenes. Root formation was quite efficient and up to two kanamycin-resistant roots per stem slice were produced. In the second step, these roots were used to regenerate transgenic plants via somatic embryogenesis. Although regeneration lasted up to 12 months, production of several transformants was successfully accomplished. Untransformed escapes were not found, indicating that the initial selection on kanamycin resistance was reliable.The presence of a combination of ROLA, B and C genes enhanced adventitious root formation on micropropagated shoots and explants of stems and leaves. It appears that the auxin sensitivity was increased to such a degree that cells were able to respond even to endogenous auxins present in shoots and leaves. Rooting experiments in greenhouse demonstrated that adventitious root formation on cuttings was improved threefold upon introduction of these ROL genes. It is concluded that a method was developed for the production of ROL gene transformed roses with improved rooting characteristics. 相似文献
998.
Simultaneous determination of amphetamine and its analogs in human whole blood by gas chromatography-mass spectrometry 总被引:1,自引:0,他引:1
Pierre Marquet Eric Lacassie Caroline Battu Huguette Faubert Grard Lachtre 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1997,700(1-2):77-82
A sensitive and specific gas chromatography-mass spectrometry (GC-MS) method for the determination of amphetamine (AM), methamphetamine (MA), methylenedioxyamphetamine (MDA), methylenedioxymethamphetamine (MDMA) and methylenedioxyethylamphetamine (MDEA) in whole blood was designed, using the respective pentadeuterated analogs of the analytes as internal standards (I.S.). After alkalinisation of blood samples, the amphetamines were extracted using diethyl ether, derivatized with heptafluorobutyric anhydride, then purified by successive washings with deionized water and 4% NH4OH. Extraction recoveries were 85.2% for AM, 90.9% for MA, 76.5% for MDA, 84.1% for MDMA and 63.6% for MDEA. Chromatographic separation was performed on a non-polar 30 m×0.32 mm HP 5 MS capillary column using a temperature program. Detection was carried out in the electron-impact, selected ion-monitoring mode, using three mass-to-charge ratios for each analyte and one for each I.S. Limits of detection ranged from 0.5 to 8 ng/ml and limits of quantification were 10 ng/ml for AM, MDMA and MDEA; 20 ng/ml for MA; and 50 ng/ml for MDA. The method was linear from this limit up to 1000 ng/ml for all analytes, with good intra-assay precision and good intermediate precision and accuracy over these ranges. There was no interferences from other sympathomimetic drugs such as ephedrine, norephedrine or methoxyphenamine. This method is thus suitable for clinical and forensic toxicology, as well as for doping control. 相似文献
999.
Caroline Capillon Anne Atlan 《Evolution; international journal of organic evolution》1999,53(2):506-517
Sex-ratio drive is a particular case of meiotic drive, described in several Drosophila species, that causes males bearing driving X chromosome to produce a large excess of females in their progeny. In Drosophila simulans, driving X chromosomes and resistance factors located on the Y chromosome and on the autosomes have been previously reported. In this paper, we report the study of the dynamics of sex-ratio factors in experimental populations. We followed the evolution in frequency of driving X chromosomes in the absence of resistance factors and the evolution of resistance factors in the presence of driving X chromosomes. The driving X chromosome was lost, contrarily to theoretical expectations that predict its rapid invasion. Autosomal resistances increased in frequency, and resistant Y chromosomes invaded the population very quickly, as predicted by theoretical models. Fitness measurements showed that the loss of the driving X chromosome was due to a strong deleterious effect that was expressed only when distorting males were in competition with standard males. However, the spread of autosomal resistances reduced this deleterious effect. Implications for the maintenance of polymorphism in natural populations are discussed. 相似文献