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121.
Hassanin A Ropiquet A Cornette R Tranier M Pfeffer P Candegabe P Lemaire M 《Comptes rendus biologies》2006,329(2):124-135
The kouprey (Bos sauveli Urbain, 1937) is a very rare bovid species of Cambodia, which may be extinct in the wild, as no living specimen has been observed for a long time. Here, we describe a complete taxidermy mount, which presents astonishing morphological similarities with the kouprey. The animal was mounted in 1871 at the National Museum of Natural History in Paris, where it was referenced as No. 1871-576. It was deposited at the Natural History Museum of Bourges, France, in 1931, where it is still conserved today. To clarify the taxonomic status of the specimen of Bourges, DNA was extracted from a piece of bone taken on the mandible, and two different fragments of the mitochondrial cytochrome b gene were independently amplified and sequenced. The phylogenetic analyses show that the specimen of Bourges is robustly associated with the holotype of the kouprey, and that both are related to other wild species of Bos found in Indochina, i.e., banteng (B. javanicus) and gaur (B. frontalis). Because of doubts for sexing the animal, we applied a molecular test based on the PCR amplification of a DNA fragment specific to the Y chromosome. The results indicate that the specimen of Bourges is a male. The comparisons with male kouprey previously described in the literature reveal important differences concerning the body size, general coloration and horns. As these differences involve phenotypic traits that are strongly selected in case of domestication, we suggest that the specimen of Bourges was a domestic ox. This implies therefore that the kouprey may have been domesticated in Cambodia, and that several extant local races may be directly related to the kouprey. 相似文献
122.
Peter R. Bieck Karl-Heinz Antonin Gisbert Farger Erik B. Nilsson Eckhart K. Schmidt Philippe Dostert Margherita Strolin Benedetti Peter C. Waldmeier 《Neurochemical research》1993,18(11):1163-1167
CGP 28 014 is a specific inhibitor of catechol-O-methyltransferase (COMT) in vivo. In humans, the inhibition was assessed by measuring urinary excretion of isoquinolines and with the levodopa test. Following administration of CGP 28 014, urinary excretion of isoquinolines was significantly increased. In rats, CGP 28 014 reduced plasma and striatal concentrations of 3-O-methyldopa (30MD) in a dose-dependent manner. Acute and subchronic administration of CGP 28 014 alone or in combination with the peripherally acting decarboxylase inhibitor benserazide decreased plasma 30MD as an index of COMT inhibition by about 50%. There seems to be a close relationship between the time-course of plasma concentrations of CGP 28 014 and the extent of COMT inhibition assessed by the 30MD/DOPA ratio in plasma. 相似文献
123.
Darrell R. Davis Philippe C. Durant 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):1579-1581
Abstract NMR spectroscopy was used to determine the solution structures of RNA oligonucleotides comprising the anticodon domain of tRNALys,3. The structural effects of the pseudouridine modification at position 39 were investigated and are well correlated with changes in thermodynamic parameters. The loop conformation differs from that seen in tRNAPhe and provides an explanation of the critical role of modification in this tRNA. 相似文献
124.
Francesca Megiorni Giovanni Luca Gravina Simona Camero Simona Ceccarelli Andrea Del Fattore Vincenzo Desiderio Federica Papaccio Heather P. McDowell Rajeev Shukla Antonio Pizzuti Filip Beirinckx Philippe Pujuguet Laurent Saniere Ellen Van der Aar Roberto Maggio Francesca De Felice Cinzia Marchese Carlo Dominici Vincenzo Tombolini Claudio Festuccia Francesco Marampon 《Journal of hematology & oncology》2017,10(1):161
Background
EPH (erythropoietin-producing hepatocellular) receptors are clinically relevant targets in several malignancies. This report describes the effects of GLPG1790, a new potent pan-EPH inhibitor, in human embryonal rhabdomyosarcoma (ERMS) cell lines.Methods
EPH-A2 and Ephrin-A1 mRNA expression was quantified by real-time PCR in 14 ERMS tumour samples and in normal skeletal muscle (NSM). GLPG1790 effects were tested in RD and TE671 cell lines, two in vitro models of ERMS, by performing flow cytometry analysis, Western blotting and immunofluorescence experiments. RNA interfering experiments were performed to assess the role of specific EPH receptors. Radiations were delivered using an x-6 MV photon linear accelerator. GLPG1790 (30 mg/kg) in vivo activity alone or in combination with irradiation (2 Gy) was determined in murine xenografts.Results
Our study showed, for the first time, a significant upregulation of EPH-A2 receptor and Ephrin-A1 ligand in ERMS primary biopsies in comparison to NSM. GLPG1790 in vitro induced G1-growth arrest as demonstrated by Rb, Cyclin A and Cyclin B1 decrease, as well as by p21 and p27 increment. GLPG1790 reduced migratory capacity and clonogenic potential of ERMS cells, prevented rhabdosphere formation and downregulated CD133, CXCR4 and Nanog stem cell markers. Drug treatment committed ERMS cells towards skeletal muscle differentiation by inducing a myogenic-like phenotype and increasing MYOD1, Myogenin and MyHC levels. Furthermore, GLPG1790 significantly radiosensitized ERMS cells by impairing the DNA double-strand break repair pathway. Silencing of both EPH-A2 and EPH-B2, two receptors preferentially targeted by GLPG1790, closely matched the effects of the EPH pharmacological inhibition. GLPG1790 and radiation combined treatments reduced tumour mass by 83% in mouse TE671 xenografts.Conclusions
Taken together, our data suggest that altered EPH signalling plays a key role in ERMS development and that its pharmacological inhibition might represent a potential therapeutic strategy to impair stemness and to rescue myogenic program in ERMS cells.125.
Caberg JH Hubert P Herman L Herfs M Roncarati P Boniver J Delvenne P 《Cancer immunology, immunotherapy : CII》2009,58(1):39-47
Human papillomavirus (HPV) infection, particularly type 16, is causally associated with cancer of the uterine cervix. The
persistence or progression of cervical lesions suggests that viral antigens are not adequately presented to the immune system.
This hypothesis is reinforced by the observation that most squamous intraepithelial lesions (SILs) show quantitative and functional
alterations of Langerhans cells (LC). The infiltration of immature LC in the squamous epithelium is mainly controlled by Macrophage
Inflammatory Protein 3α/CCL20. After having shown that CCL20 production is altered in HPV-transformed keratinocytes (KC),
the possible role of HPV16 E6 and E7 viral oncoproteins in the reduced CCL20 levels observed in SILs was investigated by silencing
HPV16 E6 and E7 oncogenes by RNA interference (siRNA). This treatment not only increased CCL20 secretion but also resulted
in the modulation of NF-κB p50, p52 and p65 precursor localization. Moreover, silencing of E6 and E7 oncogenes in HPV16-transformed
KC induced a significantly higher migratory capacity of LC in a Boyden chamber assay and in an in vitro formed (pre)neoplastic
epithelium reminiscent of high-grade SILs. Anti-CCL20 neutralizing antibody experiments showed that the increased migration
of LC is due to the re-expression of CCL20 in E6 and E7 siRNA transfected KC. These data suggest that HPV16 E6/E7-induced
down-regulation of CCL20 observed during the cervical carcinogenesis may contribute to a diminished capacity of the immune
system to control HPV infection.
P. Hubert and J. H. Caberg contributed equally to this work. 相似文献
126.
Susanne Siebentritt Enrico Avancini Marcus Br Jakob Bombsch Emilie Bourgeois Stephan Buecheler Romain Carron Celia Castro Sebastien Duguay Roberto Flix Evelyn Handick Dimitrios Hariskos Ville Havu Philip Jackson Hannu‐Pekka Komsa Thomas Kunze Maria Malitckaya Roberto Menozzi Milos Nesladek Nicoleta Nicoara Martti Puska Mohit Raghuwanshi Philippe Pareige Sascha Sadewasser Giovanna Sozzi Ayodhya Nath Tiwari Shigenori Ueda Arantxa Vilalta‐Clemente Thomas Paul Weiss Florian Werner Regan G. Wilks Wolfram Witte Max Hilaire Wolter 《Liver Transplantation》2020,10(8)
127.
128.
The synchrony effect refers to the beneficial impact of temporal matching between the timing of cognitive task administration and preferred time-of-day for diurnal activity. Aging is often associated with an advance in sleep-wake timing and concomitant optimal performance levels in the morning. In contrast, young adults often perform better in the evening hours. So far, the synchrony effect has been tested at fixed clock times, neglecting the individual's sleep-wake schedule and thus introducing confounds, such as differences in accumulated sleep pressure or circadian phase, which may exacerbate synchrony effects. To probe this hypothesis, the authors tested older morning and young evening chronotypes with a psychomotor vigilance and a Stroop paradigm once at fixed morning and evening hours and once adapting testing time to their preferred sleep-wake schedule in a within-subject design. The authors observe a persistence of synchrony effects for overall median reaction times during a psychomotor vigilance task, even when testing time is adapted to the specific individual's sleep-wake schedule. However, data analysis also indicates that time-of-day modulations are weakened under those conditions for incongruent trials on Stroop performance and the slowest reaction times on the psychomotor vigilance task. The latter result suggests that the classically observed synchrony effect may be partially mediated by a series of parameters, such as differences in socio-professional timing constraints, the amount of accumulated sleep need, or circadian phase, all leading to differential arousal levels at testing. 相似文献
129.
Lutringer-Magnin D Girard N Cadranel J Leroux C Quoix E Cottin V Del Signore C Lebitasy MP Cordier G Vanhems P Mornex JF 《PloS one》2012,7(5):e37889
Pneumonic-type lung adenocarcinoma (P-ADC) represents a distinct subset of lung cancer with specific clinical, radiological, and pathological features. Given the weak association with tobacco-smoking and the striking similarities with jaagsiekte sheep retrovirus (JSRV)-induced ovine pulmonary adenocarcinoma, it has been suggested that a zoonotic viral agent infecting pulmonary cells may predispose to P-ADC in humans. Our objective was to explore whether exposure to domestic small ruminants may represent a risk factor for P-ADC. We performed a multicenter case-control study recruiting patients with P-ADC as cases and patients with non-P-ADC non-small cell lung cancer as controls. A dedicated 356-item questionnaire was built to evaluate exposure to livestock. A total of 44 cases and 132 controls were included. At multivariate analysis, P-ADC was significantly more associated with female gender (Odds-ratio (OR)?=?3.23, 95% confidence interval (CI): 1.32-7.87, p?=?0.010), never-smoker status (OR?=?3.57, 95% CI: 1.27-10.00, p?=?0.015), personal history of extra-thoracic cancer before P-ADC diagnosis (OR?=?3.43, 95% CI: 1.10-10.72, p?=?0.034), and professional exposure to goats (OR?=?5.09, 95% CI: 1.05-24.69, p?=?0.043), as compared to other subtypes of lung cancer. This case-control suggests a link between professional exposure to goats and P-ADC, and prompts for further epidemiological evaluation of potential environmental risk factors for P-ADC. 相似文献
130.
Sandrine Vuillaumier-Barrot Céline Bouchet-Séraphin Malika Chelbi Louise Devisme Samuel Quentin Steven Gazal Annie Laquerrière Catherine Fallet-Bianco Philippe Loget Sylvie Odent Dominique Carles Anne Bazin Jacqueline Aziza Alix Clemenson Fabien Guimiot Maryse Bonnière Sophie Monnot Christine Bole-Feysot Jean-Pierre Bernard Laurence Loeuillet Marie Gonzales Koryna Socha Bernard Grandchamp Tania Attié-Bitach Férechté Encha-Razavi Nathalie Seta 《American journal of human genetics》2012,91(6):1135-1143
Cobblestone lissencephaly is a peculiar brain malformation with characteristic radiological anomalies. It is defined as cortical dysplasia that results when neuroglial overmigration into the arachnoid space forms an extracortical layer that produces agyria and/or a “cobblestone” brain surface and ventricular enlargement. Cobblestone lissencephaly is pathognomonic of a continuum of autosomal-recessive diseases characterized by cerebral, ocular, and muscular deficits. These include Walker-Warburg syndrome, muscle-eye-brain disease, and Fukuyama muscular dystrophy. Mutations in POMT1, POMT2, POMGNT1, LARGE, FKTN, and FKRP identified these diseases as alpha-dystroglycanopathies. Our exhaustive screening of these six genes, in a cohort of 90 fetal cases, led to the identification of a mutation in only 53% of the families, suggesting that other genes might also be involved. We therefore decided to perform a genome-wide study in two multiplex families. This allowed us to identify two additional genes: TMEM5 and ISPD. Because TMEM has a glycosyltransferase domain and ISPD has an isoprenoid synthase domain characteristic of nucleotide diP-sugar transferases, these two proteins are thought to be involved in the glycosylation of dystroglycan. Further screening of 40 families with cobblestone lissencephaly identified nonsense and frameshift mutations in another four unrelated cases for each gene, increasing the mutational rate to 64% in our cohort. All these cases displayed a severe phenotype of cobblestone lissencephaly A. TMEM5 mutations were frequently associated with gonadal dysgenesis and neural tube defects, and ISPD mutations were frequently associated with brain vascular anomalies. 相似文献