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A novel antigen preparation--the synthetic C6 peptide, a conserved portion of the variable VlsE antigens of Borrelia burgdorferi--has been evaluated for serodiagnosis of Lyme borreliosis (LB) by an ELISA procedure. Serum specimens were from early and late LB patients, all resident in an endemic area in north-eastern Italy. The specificity of the test approached the 100% and sensitivity was in the order of 63% (early LB) and 100% (late LB); this performance is superior to the preceding generation of Lyme disease tests. 相似文献
53.
Genetic variation in five Mediterranean populations of Juniperus phoenicea as revealed by inter-simple sequence repeat (ISSR) markers 总被引:4,自引:0,他引:4
BACKGROUND AND AIMS: The assessment of the genetic variability and the identification of isolated populations within a given species represent important information to plan conservation strategies on a genetic basis. In this work, the genetic variability in five natural populations of Juniperus phoenicea, three from Sardinia, one from Cyprus and the last one in the Maritime Alps was analysed by means of ISSRs, on the hypothesis that the latter could have been a refugial one during the last glaciation. METHODS: ISSRs were chosen because of their ability to detect variation without any prior sequence information. The use of three primers yielded 45 reproducible, polymorphic bands, which were utilized to estimate the basic parameters of genetic variability and diversity. KEY RESULTS: All of the populations analysed harboured an adequate amount of genetic variability, with H(S) = 0.1299. The proportion of genetic diversity between populations has been estimated by G(ST) = 0.12. The three Sardinian populations are separated, as tested by AMOVA, from the Cyprus and the continental ones. CONCLUSIONS: The results indicate that geographical isolation has represented a major barrier to gene flow in Juniperus phoenicea. This work represents a first step towards a full genetic characterization of a conifer from the Mediterranean, a world biodiversity hotspot confronted with climate change, and thus contributes towards the planning of genetics-informed conservation strategies. 相似文献
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Recalcati MP Bellini M Norsa L Ballarati L Caselli R Russo S Larizza L Giardino D 《Gene》2012,502(1):40-45
We describe a 7-year-old boy with a complex rearrangement involving the whole short arm of chromosome 9 defined by means of molecular cytogenetic techniques. The rearrangement is characterized by a 18.3 Mb terminal deletion associated with the inverted duplication of the adjacent 21,5 Mb region. The patient shows developmental delay, psychomotor retardation, hypotonia. Other typical features of 9p deletion (genital disorders, midface hypoplasia, long philtrum) and of the 9p duplication (brachycephaly, down slanting palpebral fissures and bulbous nasal tip) are present. Interestingly, he does not show trigonocephaly that is the most prominent dysmorphism associated with the deletion of the short arm of chromosome 9. Patient's phenotype and the underlying flanking opposite 9p imbalances are compared with that of reported patients and the proposed critical regions for 9p deletion and 9p duplication syndromes. 相似文献
56.
Giovanna De Chiara Maria Elena Marcocci Rossella Sgarbanti Livia Civitelli Cristian Ripoli Roberto Piacentini Enrico Garaci Claudio Grassi Anna Teresa Palamara 《Molecular neurobiology》2012,46(3):614-638
A growing body of epidemiologic and experimental data point to chronic bacterial and viral infections as possible risk factors for neurodegenerative diseases, including Alzheimer??s disease, Parkinson??s disease and amyotrophic lateral sclerosis. Infections of the central nervous system, especially those characterized by a chronic progressive course, may produce multiple damage in infected and neighbouring cells. The activation of inflammatory processes and host immune responses cause chronic damage resulting in alterations of neuronal function and viability, but different pathogens can also directly trigger neurotoxic pathways. Indeed, viral and microbial agents have been reported to produce molecular hallmarks of neurodegeneration, such as the production and deposit of misfolded protein aggregates, oxidative stress, deficient autophagic processes, synaptopathies and neuronal death. These effects may act in synergy with other recognized risk factors, such as aging, concomitant metabolic diseases and the host??s specific genetic signature. This review will focus on the contribution given to neurodegeneration by herpes simplex type-1, human immunodeficiency and influenza viruses, and by Chlamydia pneumoniae. 相似文献
57.
Ghezzi D Baruffini E Haack TB Invernizzi F Melchionda L Dallabona C Strom TM Parini R Burlina AB Meitinger T Prokisch H Ferrero I Zeviani M 《American journal of human genetics》2012,90(6):1079-1087
Dysfunction of mitochondrial respiration is an increasingly recognized cause of isolated hypertrophic cardiomyopathy. To gain insight into the genetic origin of this condition, we used next-generation exome sequencing to identify mutations in MTO1, which encodes mitochondrial translation optimization 1. Two affected siblings carried a maternal c.1858dup (p.Arg620Lysfs∗8) frameshift and a paternal c.1282G>A (p.Ala428Thr) missense mutation. A third unrelated individual was homozygous for the latter change. In both humans and yeast, MTO1 increases the accuracy and efficiency of mtDNA translation by catalyzing the 5-carboxymethylaminomethylation of the wobble uridine base in three mitochondrial tRNAs (mt-tRNAs). Accordingly, mutant muscle and fibroblasts showed variably combined reduction in mtDNA-dependent respiratory chain activities. Reduced respiration in mutant cells was corrected by expressing a wild-type MTO1 cDNA. Conversely, defective respiration of a yeast mto1Δ strain failed to be corrected by an Mto1Pro622∗ variant, equivalent to human MTO1Arg620Lysfs∗8, whereas incomplete correction was achieved by an Mto1Ala431Thr variant, corresponding to human MTO1Ala428Thr. The respiratory yeast phenotype was dramatically worsened in stress conditions and in the presence of a paromomycin-resistant (PR) mitochondrial rRNA mutation. Lastly, in vivo mtDNA translation was impaired in the mutant yeast strains. 相似文献
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Ceci M Welshhans K Ciotti MT Brandi R Parisi C Paoletti F Pistillo L Bassell GJ Cattaneo A 《PloS one》2012,7(4):e35034
In neurons, specific mRNAs are transported in a translationally repressed manner along dendrites or axons by transport ribonucleic-protein complexes called RNA granules. ZBP1 is one RNA binding protein present in transport RNPs, where it transports and represses the translation of cotransported mRNAs, including β-actin mRNA. The release of β-actin mRNA from ZBP1 and its subsequent translation depends on the phosphorylation of ZBP1 by Src kinase, but little is known about how this process is regulated. Here we demonstrate that the ribosomal-associated protein RACK1, another substrate of Src, binds the β-actin mRNA/ZBP1 complex on ribosomes and contributes to the release of β-actin mRNA from ZBP1 and to its translation. We identify the Src binding and phosphorylation site Y246 on RACK1 as the critical site for the binding to the β-actin mRNA/ZBP1 complex. Based on these results we propose RACK1 as a ribosomal scaffold protein for specific mRNA-RBP complexes to tightly regulate the translation of specific mRNAs. 相似文献
60.
Nappi RE Nappi G 《Gynecological endocrinology : the official journal of the International Society of Gynecological Endocrinology》2012,28(Z1):37-41
Migraine is a complex disabling disease influenced mainly by age and gender during the life span. Neuroendocrine events related to reproductive stages and to the menstrual cycle may cause significant change in the clinical pattern of migraine over time, as a consequence of failure in adaptation higher in women than in men. Indeed, the individual threshold of vulnerability to manifest migraine is modulated by hormonal fluctuations naturally occurring throughout the menstrual cycle and at the time of reproductive transitions. In the present short review, the role of endogenous estrogen at the level of brain circuitries which are involved in multiple cellular, neurochemical and neurophysiological processes associated with migraine will be summarized in the context of reproductive milestones. In addition, some clues to recognize hormonally sensitive women on the basis of their migraine history, i.e. onset, association with menstruation or premenstrual syndrome, course during pregnancy and menopause, will be discussed in order to expand the knowledge of reproductive endocrinology in the management of migraine in women. 相似文献