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1.
Summary Chromosome aberrations permit the assignment to and the exclusion of genes on certain chromosomes or definite segments. Only exclusion methods are discussed. All relevant data are compiled in a table from which it can be determined, which genetic systems are excluded from certain autosomal segments.
Direktor: Prof. Dr. Dr. H. Baitsch
Supported by the Deutsche Forschungsgemeinschaft. 相似文献
Zusammenfassung Angeborene Chromosomenaberrationen ermöglichen die Zuordnung und den Ausschluß von Genen auf dem betroffenen Segment. Nur die für Lokalisierungsausschlüsse verwendbaren Methoden werden diskutiert. Aus einer Zusammenstellung der bisherigen Befunde wird ermittelt, welche genetischen Systeme von einer Lokalisierung auf bestimmten Autosomen(segmenten) des Menschen ausgeschlossen werden können.
Direktor: Prof. Dr. Dr. H. Baitsch
Supported by the Deutsche Forschungsgemeinschaft. 相似文献
2.
Ferdane Kutlar Jose M. Gonzalez-Redondo Abdullah Kutlar Aytemiz Gurgey Çigdem Altay Georgi D. Efremov Klara Kleman Titus H. J. Huisman 《Human genetics》1989,82(2):179-186
Summary Details are given of a study of blood samples from 24 patients with Hb H disease from different Mediterranean countries and from the Far East. Four different types of -thal-1 (--) were observed, namely-() ( 20.5-kb deletion);--MED-I ( 17.5-kb deletion);--MED-II (>26.5-kb deletion); and--SEA ( 18-kb deletion, in Orientals only). The -thal-2 was mainly of the deletion type (16 with the 3.7-kb deletion; 1 with the 4.2-kb deletion), while 4 of the 7 patients with a nondeletional type had the five-nucleotide deletion at the donor splice site of the first intron of the 2 gene. All patients had a mild-to-moderate hemolytic anemia; no significant differences in hematology were observed between the groups. Hb A2 was decreased to about one-third of the normal level. The Hb H formation varied considerably and its quantitation was not always satisfactory. Patients with Hb H disease due to any -thal-1 combined with a nondeletional -thal-2 had the highest Hb H levels and a more marked anemia. The chain production was small and absent in patients with the MED-II type of -thal-1 because this deletion included the and genes. The highest chain levels were present in the four patients with the SEA type of -thal-1. The chain production was increased, particularly in patients with a mutation of C T at position-158 to the G globin gene. This chain was primarily present as Hb Bart's (or 4) and only about 15% was recovered as Hb F or 22. The evaluation of the rate of chains produced in these patients was greatly facilitated by data from one patient who had Hb H disease and a heterozygosity for the A-+. The low levels of Hb A2 and of Hb F (relative to Hb Bart's) can be explained by a decreased affinity of chains for and chains as compared with chains in conditions of severe chain deficiency. 相似文献
3.
Batdorj Enkhjin AlOgayil Najla Zhuang Qinwei Kim-wee Galvez Jose Hector Bauermeister Klara Nagata Kei Kimura Tohru Ward Monika A. Taketo Teruko Bourque Guillaume Naumova Anna K. 《Mammalian genome》2023,34(1):44-55
Mammalian Genome - Several lines of evidence suggest that the presence of the Y chromosome influences DNA methylation of autosomal loci. To better understand the impact of the Y chromosome on... 相似文献
4.
5.
Arun K Mankan Marion Goldeck Klara Höning Moritz Gaidt Andrew V Kubarenko Liudmila Andreeva Karl‐Peter Hopfner Veit Hornung 《The EMBO journal》2014,33(24):2937-2946
Intracellular recognition of non‐self and also self‐nucleic acids can result in the initiation of potent pro‐inflammatory and antiviral cytokine responses. Most recently, cGAS was shown to be critical for the recognition of cytoplasmic dsDNA. Binding of dsDNA to cGAS results in the synthesis of cGAMP(2′–5′), which then binds to the endoplasmic reticulum resident protein STING. This initiates a signaling cascade that triggers the induction of an antiviral immune response. While most studies on intracellular nucleic acids have focused on dsRNA or dsDNA, it has remained unexplored whether cytosolic RNA:DNA hybrids are also sensed by the innate immune system. Studying synthetic RNA:DNA hybrids, we indeed observed a strong type I interferon response upon cytosolic delivery of this class of molecule. Studies in THP‐1 knockout cells revealed that the recognition of RNA:DNA hybrids is completely attributable to the cGAS–STING pathway. Moreover, in vitro studies showed that recombinant cGAS produced cGAMP upon RNA:DNA hybrid recognition. Altogether, our results introduce RNA:DNA hybrids as a novel class of intracellular PAMP molecules and describe an alternative cGAS ligand next to dsDNA. 相似文献
6.
Swift LL Zhu MY Kakkad B Jovanovska A Neely MD Valyi-Nagy K Roberts RL Ong DE Jerome WG 《Journal of lipid research》2003,44(10):1841-1849
Microsomal triglyceride transfer protein (MTP) is essential for the assembly of apolipoprotein B-containing lipoproteins. Within the endoplasmic reticulum, it transfers lipid from the membrane to the forming lipoprotein. Recent evidence suggests that it may also function within the Golgi apparatus. To address this hypothesis, we developed a polyclonal antibody to MTP and used it in a series of studies on mouse liver and McArdle-RH7777 (McA) cells. Western blot analysis demonstrated the presence of MTP within mouse hepatic-Golgi apparatus-rich fractions. In addition, in vitro lipid transfer assays demonstrated the presence of triglyceride transfer activity within the Golgi fractions. Immunohistochemical studies with mouse liver demonstrated the presence of MTP within all hepatocytes, but not in nonparenchymal cells. The subcellular location of MTP in McA cells was investigated using confocal microscopy. MTP colocalized with the trans-Golgi network (TGN) 38 and Golgi SNARE (soluble N-ethylmalemide-sensitive factor attachment protein receptor) of 28 kDa (GS28), markers for the trans- and cis-Golgi apparatus, respectively. Morphometric analyses indicated that approximately 17% of the MTP signal colocalized with the TGN38, while 33% of the trans-Golgi marker colocalized with the MTP. Approximately 17% of the MTP signal colocalized with the GS28, whereas 53% of the cis-Golgi marker colocalized with the MTP. The results provide unequivocal evidence for the location of MTP within the Golgi apparatus, and further highlight the importance of this organelle in the assembly of lipoproteins. 相似文献
7.
Klara M. Wanelik Joanne S. Griffin Megan L. Head Fiona C. Ingleby Zenobia Lewis 《Ecology and evolution》2020,10(14):6870-6880
The academic disciplines of Science, Technology, Engineering and Mathematics (STEM) have long suffered from a lack of diversity. While in recent years there has been some progress in addressing the underrepresentation of women in STEM subjects, other characteristics that have the potential to impact on equality of opportunity have received less attention. In this study, we surveyed 188 early career scientists (ECRs), defined as within 10 years of completing their PhD, in the fields of ecology, evolutionary biology, behaviour, and related disciplines. We examined associations between ethnicity, age, sexual orientation, sex, socioeconomic background, and disability, with measures of career progression, namely publication record, number of applications made before obtaining a postdoc, type of contract, and number of grant applications made. We also queried respondents on perceived barriers to progression and potential ways of overcoming them. Our key finding was that socioeconomic background and ethnicity were associated with measures of career progression. While there was no difference in the number of reported first‐authored papers on PhD completion, ethnic minority respondents reported fewer other‐authored papers. In addition, ECRs from a lower socioeconomic background were more likely to report being in teaching and research positions, rather than research‐only positions, the latter being perceived as more prestigious by some institutions. We discuss our findings in the context of possible inequality of opportunity. We hope that this study will stimulate wider discussion and help to inform strategies to address the underrepresentation of minority groups in the fields of ecology and evolution, and STEM subjects more widely. 相似文献
8.
Continuous-time Markov processes are often used to model the complex natural phenomenon of sequence evolution. To make the process of sequence evolution tractable, simplifying assumptions are often made about the sequence properties and the underlying process. The validity of one such assumption, time-homogeneity, has never been explored. Violations of this assumption can be found by identifying non-embeddability. A process is non-embeddable if it can not be embedded in a continuous time-homogeneous Markov process. In this study, non-embeddability was demonstrated to exist when modelling sequence evolution with Markov models. Evidence of non-embeddability was found primarily at the third codon position, possibly resulting from changes in mutation rate over time. Outgroup edges and those with a deeper time depth were found to have an increased probability of the underlying process being non-embeddable. Overall, low levels of non-embeddability were detected when examining individual edges of triads across a diverse set of alignments. Subsequent phylogenetic reconstruction analyses demonstrated that non-embeddability could impact on the correct prediction of phylogenies, but at extremely low levels. Despite the existence of non-embeddability, there is minimal evidence of violations of the local time homogeneity assumption and consequently the impact is likely to be minor. 相似文献
9.
Mihola Ondrej Kobets Tatyana Krivankova Klara Linhartova Eliska Gasic Srdjan Schimenti John C. Trachtulec Zdenek 《Chromosoma》2020,129(1):69-82
Chromosoma - Long transgenes are often used in mammalian genetics, e.g., to rescue mutations in large genes. In the course of experiments addressing the genetic basis of hybrid sterility caused by... 相似文献
10.
Klara K. Nordn Jaeike W. Faber Frane Babarovi Thomas L. Stubbs Tara Selly James D. Schiffbauer Petra Peharec tefani Gerald Mayr Fiann M. Smithwick Jakob Vinther 《Evolution; international journal of organic evolution》2019,73(1):15-27
Some of the most varied colors in the natural world are created by iridescent nanostructures in bird feathers, formed by layers of melanin‐containing melanosomes. The morphology of melanosomes in iridescent feathers is known to vary, but the extent of this diversity, and when it evolved, is unknown. We use scanning electron microscopy to quantify the diversity of melanosome morphology in iridescent feathers from 97 extant bird species, covering 11 orders. In addition, we assess melanosome morphology in two Eocene birds, which are the stem lineages of groups that respectively exhibit hollow and flat melanosomes today. We find that iridescent feathers contain the most varied melanosome morphologies of all types of bird coloration sampled to date. Using our extended dataset, we predict iridescence in an early Eocene trogon (cf. Primotrogon) but not in the early Eocene swift Scaniacypselus, and neither exhibit the derived melanosome morphologies seen in their modern relatives. Our findings confirm that iridescence is a labile trait that has evolved convergently in several lineages extending down to paravian theropods. The dataset provides a framework to detect iridescence with more confidence in fossil taxa based on melanosome morphology. 相似文献