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61.
Generation of dwarf goat (Capra hircus) clones following nuclear transfer with transfected and nontransfected fetal fibroblasts and in vitro-matured oocytes 总被引:22,自引:0,他引:22
Keefer CL Baldassarre H Keyston R Wang B Bhatia B Bilodeau AS Zhou JF Leduc M Downey BR Lazaris A Karatzas CN 《Biology of reproduction》2001,64(3):849-856
The developmental potential of caprine fetal fibroblast nuclei after in vitro transfection and nuclear transfer (NT) into enucleated, in vitro-matured oocytes was evaluated. Fetal fibroblasts were isolated from Day 27 to Day 30 fetuses from a dwarf breed of goat (BELE: breed early lactate early). Cells were transfected with constructs containing the enhanced green fluorescent protein (eGFP) and neomycin resistance genes and were selected with G418. Three eGFP lines and one nontransfected line were used as donor cells in NT. Donor cells were cultured in Dulbecco minimum Eagle medium plus 0.5% fetal calf serum for 4-8 days prior to use in NT. Immature oocytes were recovered by laparoscopic ovum pick-up and matured for 24 h prior to enucleation and NT. Reconstructed embryos were transferred as cleaved embryos into synchronized recipients. A total of 27 embryos derived from transgenic cells and 70 embryos derived from nontransgenic cells were transferred into 13 recipients. Five recipients (38%) were confirmed pregnant at Day 35 by ultrasound. Of these, four recipients delivered five male kids (7.1% of embryos transferred) derived from the nontransfected line. One recipient delivered a female kid derived from an eGFP line (7.7% of embryos transferred for that cell line). Presence of the eGFP transgene was confirmed by polymerase chain reaction, Southern blotting, and fluorescent in situ hybridization analyses. Nuclear transfer derivation from the donor cells was confirmed by single-strand confirmation polymorphism analysis. These results demonstrate that both in vitro-transfected and nontransfected caprine fetal fibroblasts can direct full-term development following NT. 相似文献
62.
Sharaf Al-Tardeh Thomas Sawidis Barbara -Evelin Diannelidis Stylianos Delivopoulos 《Journal of Plant Biology》2008,51(2):150-158
The morpho-anatomy and histochemistry of the hysteranthous leaf ofUrginea maritima (L.) Baker and its adaptive strategies to the Mediterranean climate were investigated. The leaf ofU. maritima is 714 μm thick and possesses moderate specific leaf mass (8.564 mg cm-2) and low tissue density (136.5 mg cm-3). The epidermal cells are compactly arranged and covered with cuticle. The average density of stomata in lower epidermis
is higher than that of the upper one. The mesophyll cells occupy 52.96% of the total volume of the leaf, while the mesophyll
intercellular spaces and the air spaces occupy 30.41%. Idioblastic cells containing raphide bundles and different phenotypes
of crystalloid inclusions, embedded in polysaccharides, occur in the lower side of the mesophyll. The presence of oil droplets
and lipids is evident. Bundle sheath cells are hardly visible with no chloroplasts which are a pronounced C3 plant character. Plastids containing protein crystalloid inclusions are abundant in the protophloem sieve elements.U. maritima, a deciduous plant, possesses leaves with mesophytic characters, in order to optimize its adaptation to the seasonal fluctuation
of environmental conditions of the Mediterranean climate. 相似文献
63.
Anastasios Karatzas Vassilios Tzortzis Eirini Giannatou Stavros Gravas Ioannis Zachos Athanassios Oeconomou Michael Melekos Aspasia Tsezou 《Molecular biology reports》2013,40(12):6665-6669
Glucuronidation, mediated by the UDP-glucuronosyltransferase 1A1 (UGT1A1) enzyme, is an important metabolic process during which steroids are converted to more easily excreted compounds in steroid target tissues, such as the prostate. The aim of our study was to investigate the possible correlation between UGT1A1 promoter gene polymorphism and benign prostatic hyperplasia. 421 blood samples were obtained from 138 consecutive patients diagnosed with benign prostatic hypeplasia (BPH group) and 283 healthy volunteers (control group). A(TA)6TAA promoter polymorphism of UGT1A1 gene was studied using the Fragment Analysis Software of an automated DNA sequencer and three genotypes (homozygous 7/7, heterozygous 6/7 and normal homozygous 6/6) were identified. No significant differences were observed between the BPH group and controls regarding the genotyping distribution of the three UGT1A1 promoter genotypes (P = 0.39). Also, no association was found between overall disease risk and the presence of the polymorphic homozygous genotype (TA(7)/TA)7) vs. TA(6)/TA(7) + TA(6)/TA(6)) (P = 0.31). Our data suggest that the TA repeat polymorphism of UGT1A1 is not associated with increased BPH risk susceptibility in Caucasian men. 相似文献
64.
Neutrophil CD64 expression and serum IL-8: sensitive early markers of severity and outcome in sepsis
Livaditi O Kotanidou A Psarra A Dimopoulou I Sotiropoulou C Augustatou K Papasteriades C Armaganidis A Roussos C Orfanos SE Douzinas EE 《Cytokine》2006,36(5-6):283-290
The aim of the present study was to investigate which biomarker/s reliably assess severity and mortality early in the sepsis process. In 47 critically-ill patients within the 24h of septic onset, Interleukins (IL)-8, -1beta, -6, -10, and -12p70, tumor necrosis factor-alpha (TNF-alpha), procalcitonin (PCT) and C-reactive protein (CRP) were measured in serum. Additionally, CD64 expression was measured in neutrophils. In early sepsis, neutrophil CD64 expression and IL-8 levels are the only biomarkers that increased with sepsis severity, differentiating disease stages: sepsis, severe sepsis and septic shock (p<0.001). The biomarkers that best evaluate the severity of sepsis (via APACHE II) were CD64, IL-8 and IL-6 (p<0.01), and the severity of organ failure (via SOFA) were CD64 and IL-8 (p<0.01). CD64 expression and IL-8 levels were associated with mortality within 28-days (OR=1.3, p=0.01 for CD64 and OR=1.26, p=0.024 for IL-8 by logistic regression analysis) and ROC curve analysis showed high sensitivity and specificity for predicting sepsis stages and the 28 day mortality. We conclude that there is an early increase of neutrophil CD64 expression and IL-8 levels during sepsis. Based on this single measurement it is possible to reliably assess the stage, detect the severity and predict the 28-day mortality of sepsis. 相似文献
65.
Production of recombinant human type I procollagen homotrimer in the mammary gland of transgenic mice 总被引:8,自引:0,他引:8
Toman PD Pieper F Sakai N Karatzas C Platenburg E de Wit I Samuel C Dekker A Daniels GA Berg RA Platenburg GJ 《Transgenic research》1999,8(6):415-427
The large scale production of recombinant collagen for use in biomaterials requires an efficient expression system capable of processing a large (>400Kd) multisubunit protein requiring post-translational modifications. To investigate whether the mammary gland of transgenic animals fulfills these requirements, transgenic mice were generated containing the S1-casein mammary gland-specific promoter operatively linked to 37Kb of the human 1(I) procollagen structural gene and 3 flanking region. The frequency of transgenic lines established was 12%. High levels of soluble triple helical homotrimeric [(1)3] type I procollagen were detected (up to 8mg/ml) exclusively in the milk of six out of 9 lines of lactating transgenic mice. The transgene-derived human procollagen chains underwent efficient assembly into a triple helical structure. Although proline or lysine hydroxylation has never been described for any milk protein, procollagen was detected with these post-translational modifications. The procollagen was stable in mil; minimal degradation was observed. These results show that the mammary gland is capable of expressing a large procollagen gene construct, efficiently assembling the individual polypeptide chains into a stable triple helix, and secreting the intact molecule into the milk. 相似文献
66.
Channels directly gated by cyclic nucleotides (CNG channels) are important cellular switches that mediate influx of Na+ and Ca2+ in response to increases in the intracellular concentration of cAMP and cGMP. In photoreceptors and olfactory receptor neurons,
these channels serve as final targets for cGMP and cAMP signaling pathways that are initiated by the absorption of photons
and the binding of odorants, respectively. CNG channels have been also found in other types of neurons and in non-excitable
cells. However, in most of these cells, the physiological role of CNG channels has yet to be determined. CNG channels have
a complex heteromeric structure. The properties of individual subunits that assemble in specific stoichiometries to the native
channels have been extensively investigated in heterologous expression systems. Recently, mutations in human CNG channel genes
leading to inherited diseases (so-called channelopathies) have been functionally characterized. Moreover, mouse knockout models
were generated to define the role of CNG channel proteins in vivo. In this review, we will summarize recent insights into
the physiological and pathophysiological role of CNG channel proteins that have emerged from genetic studies in mice and humans. 相似文献
67.
Subjects with metabolic syndrome–a constellation of cardiovascular risk factors of which central obesity and insulin resistance
are the most characteristic–are at increased risk for developing diabetes mellitus and cardiovascular disease. In these subjects,
abdominal adipose tissue is a source of inflammatory cytokines such as tumor necrosis factor-alpha, known to promote insulin
resistance. The presence of inflammatory cytokines together with the well-documented increased risk for cardiovascular diseases
in patients with inflammatory arthritides and systemic lupus erythematosus has prompted studies to examine the prevalence
of the metabolic syndrome in an effort to identify subjects at risk in addition to that conferred by traditional cardiovascular
risk factors. These studies have documented a high prevalence of metabolic syndrome which correlates with disease activity
and markers of atherosclerosis. The correlation of inflammatory disease activity with metabolic syndrome provides additional
evidence for a link between inflammation and metabolic disturbances/vascular morbidity. 相似文献
68.
Exon trapping was used to identify portions of human chromosome 21-encoded genes. More than 600 potential exons on the chromosome
have been cloned and characterised to date. A BLAST search of databases revealed that three of these trapped “exons”, hmc18a08,
hmc18f10 and hmc27g09, showed strong homology to different regions of the Drosophila mnb (Genbank X70794) and rat Dyrk (Genbank X79769) genes, indicating that these three exons may be portions of a human homologue of these genes (we termed
this gene MNB for minibrain). With amplification by the polymerase chain reaction and hybridisation analysis we have mapped the human MNB gene on overlapping yeast artificial chromosomes 336G11 and 806A11 of chromosome 21q22.2 between markers D21S65 and ERG.
The Drosophila mnb (minibrain) gene, which encodes a member of the protein kinase family, is involved in postembryonic neurogenesis. The Dyrk gene, which encodes a dual specificity protein kinase, is a rat homologue of the Drosophila mnb gene. The kinase activity is dependent on tyrosine residues in the catalytic domain, and it has been speculated that the
protein is involved in control of the cell cycle. Altered expression of the human MNB gene may be involved in the pathogenesis of certain phenotypes of Down syndrome, including mental retardation.
Received: 14 June 1996 / Revised: 5 September 1996 相似文献
69.
Andrew C. Warren Nikolaos K. Robakis Narayanarao Ramakrishna Edward H. Koo Christopher A. Ross Adelaide S. Robb Marshal F. Folstein Donald L. Price Stylianos E. Antonarakis 《Genomics》1987,1(4)
Recently, it has been suggested that Alzheimer's disease is associated with a duplication of the amyloid precursor protein gene localized to chromosome 21q21. In this study, a cloned DNA probe (B2.3), complementary to the sequence coding the β-amyloid peptide, and DNA polymorphisms adjacent to this sequence were used to determine the number of copies of the β-amyloid gene in DNA isolated from human blood and brain. Individuals with trisomy 21 (Down syndrome) who were heterozygous for the polymorphisms showed a gene-dosage effect, with one allele exhibiting twice the autoradiographic intensity as the other. Heterozygous individuals with Alzheimer's disease and controls showed equal intensities of the two allelic bands, suggesting that there are only two copies of the β-amyloid gene in these individuals. In individuals with Alzheimer's disease and in controls who were homozygous for these polymorphisms, the number of copies of the β-amyloid gene was determined by comparing the autoradiographic intensity of β-amyloid alleles to that of DNA fragments detected by a reference probe. No difference was detected between these two groups. 相似文献
70.
Baldassarre H Wang B Kafidi N Gauthier M Neveu N Lapointe J Sneek L Leduc M Duguay F Zhou JF Lazaris A Karatzas CN 《Theriogenology》2003,59(3-4):831-839
Oocytes collected by laparoscopic ovum pick-up (LOPU) were successfully used to produce transgenic goats by pronuclear microinjection of in vitro zygotes. Estrus cycles of 109 donor goats were synchronized using intravaginal sponges impregnated with 60 mg of medroxyprogesterone acetate and treatment with 70 mg NIH-FSH-P1 and 300 IU eCG to stimulate follicular development. Follicles were aspirated under laparoscopic observation. In vitro maturation (IVM) of oocytes was performed in M199 supplemented with hormones, kanamycin and 10% estrus goat serum. Following IVM, oocytes were cocultured with capacitated semen in TALP supplemented with 20% estrus goat serum for 15-20 h. The resulting zygotes were microinjected with a linear DNA fragment. In total, 3293 follicles were aspirated (15.7+/-9 follicles aspirated per donor) and 2823 oocytes were recovered (13.4+/-8 oocytes per donor). A total of 1366 zygotes were microinjected and transferred into 219 recipient goats by midventral laparotomy (average 6.2 embryos per recipient). A total of 150 kids were born, of which 9 (6 M: 3 F) were confirmed to be transgenic by PCR and Southern blotting analyses. These results demonstrate that acceptable transgenesis rates can be obtained in goats by DNA microinjection of in vitro produced zygotes. 相似文献