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951.
Rudy M. Landsvater Rumo P. M. Jansen Robert M. W. Hofstra Charles H. C. M. Buys Cornelis J. M. Lips Hans Kristian Ploos van Amstel 《Human genetics》1996,97(1):11-14
Hereditary C-cell carcinoma is encountered in multiple endocrine neoplasia type 2A (MEN 2A), MEN 2B, and familial medullary thyroid carcinoma (FMTC). Mutations of the RET proto-oncogene are associated with all three diseases. To obtain an insight into the molecular heterogeneity of MEN 2 syndromes and FMTC in the Netherlands, probands of 20 MEN 2A families, two FMTC families, and seven MEN 2B families were analyzed by the polymerase chain reaction (PCR), DNA sequencing, and restriction enzyme digestion for abnormalities in the RET proto-oncogene. RET mutations were found in all cases. All MEN 2A families had a mutation involving one of five cysteine codons in exons 10 and 11 of RET. Two novel dinucleotide mutations and a de novo mutation were found. Both FMTC families had a mutation of the Cys at codon 618. All MEN 2B probands carried a Met to Thr mutation in exon 16. All mutations could be confirmed by restriction enzyme digestion of PCR amplicons. Identification of the RET mutation in the Dutch population with hereditary C-cell carcinoma facilitates genetic testing for families or individuals at risk for MEN 2A, FMTC, and MEN 2B. 相似文献
952.
George Chryssolouris James E. Pierce Kristian Dicke 《Flexible Services and Manufacturing Journal》1992,4(3-4):309-330
This paper introduces a generic decision-making framework for assigning resources of a manufacturing system to production tasks. Resources are broadly defined production units, such as machines, human operators, or material handling vehicles; and tasks are activities performed by resources. In the specific context of FMS, resources correspond to individual machines; tasks correspond to operations to be performed on parts. The framework assumes a hierarchical structure of the system and calls for the execution of four consecutive steps to make a decision for the assignment of a resource to a task. These steps are 1) establishment of decision-making criteria, 2) formation of alternative assignments, 3) estimation of the consequences of the assignments, and 4) selection of the best alternative assignment. This framework has been applied to an existing FMS as an operational policy that decides what task will be executed on which resource of this FMS. Simulation runs provide some initial results of the application of this policy. It is shown that the policy provides flexibility in terms of system performance and computational effort. 相似文献
953.
Pierre‐François Perroud Fabian B. Haas Manuel Hiss Kristian K. Ullrich Alessandro Alboresi Mojgan Amirebrahimi Kerrie Barry Roberto Bassi Sandrine Bonhomme Haodong Chen Juliet C. Coates Tomomichi Fujita Anouchka Guyon‐Debast Daniel Lang Junyan Lin Anna Lipzen Fabien Nogué Melvin J. Oliver Inés Ponce de León Ralph S. Quatrano Catherine Rameau Bernd Reiss Ralf Reski Mariana Ricca Younousse Saidi Ning Sun Péter Szövényi Avinash Sreedasyam Jane Grimwood Gary Stacey Jeremy Schmutz Stefan A. Rensing 《The Plant journal : for cell and molecular biology》2018,95(1):168-182
954.
955.
Ole Lund Ole Søgaard Lund Gregers Gram Susanne Dam Nielsen Kristian Schønning Jens Ole Nielsen John-Erik Stig Hansen Erik Mosekilde 《Bulletin of mathematical biology》1997,59(4):725-745
The paper presents a mathematical analysis of the criteria for gene therapy of T helper cells to have a clinical effect on
HIV infection. The analysis indicates that for such a therapy to be successful, it must protect the transduced cells against
HIV-induced death. The transduced cells will not survive as a population if the gene therapy only blocks the spread of virus
from transduced cells that become infected. The analysis also suggests that the degree of protection against disease-related
cell death provided by the gene therapy is more important than the fraction of cells that is initially transduced. If only
a small fraction of the cells can be transduced, transduction of T helper cells and transduction of haematopoietic progenitor
cells will result in the same steady-state level of transduced T helper cells. For gene therapy to be efficient against HIV
infection, our analysis suggests that a 100% protection against viral escape must be obtained. The study also suggests that
a gene therapy against HIV infection should be designed to give the transduced cells a partial but not necessarily total protection
against HIV-induced cell death, and to avoid the production of viral mutants insensitive to the gene therapy. 相似文献
956.
Theodor W. Blackstad Sidsel Fregerslev Sören Laurberg Kristian Rokkedal 《Histochemistry and cell biology》1973,36(3):247-268
Summary Golgi impregnation of nerve tissue can be obtained by soaking the tissue in a solution of potassium dichromate followed by a solution of mercurous or mercuric nitrate. The precipitate formed in each of these two methods has been identified. Samples of impregnated tissues were ground and examined with X-ray powder diffraction and the patterns of spacings compared both with the values of international tables (the ASTM index) and with the results of X-ray studies of substances prepared by ourselves and subjected to quantitative chemical analysis. It was found that impregnated blocks contained mercurous chromate, Hg2CrO4, after mercurous nitrate treatment, and mercuric oxide chromate, Hg3O2CrO4, after mercuric nitrate treatment. Selected area electron diffraction of ultrathin sections through impregnated nervous structures (embedded in epoxy resin) showed these to contain the substances demonstrated by X-ray analysis of whole tissue.This study was supported by U. S. P. H. S. Grant NS 07998. This aid is gratefully acknowedged. We are indebted to Mrs. E. Clausen, Mrs. K. Kirkholt, Mr. A. Meier and Mrs. K. Sörensen for technical assistance.Institute of Geology, Aarhus University, Aarhus, Denmark.We are indebted to him for the possibility of basing some of our studies on his results. 相似文献
957.
Mani Sadredini Tore Kristian Danielsen Jan Magnus Aronsen Ravinea Manotheepan Karina Hougen Ivar Sjaastad Mathis Korseberg Stokke 《PloS one》2016,11(4)
Abnormal cellular Ca2+ handling contributes to both contractile dysfunction and arrhythmias in heart failure. Reduced Ca2+ transient amplitude due to decreased sarcoplasmic reticulum Ca2+ content is a common finding in heart failure models. However, heart failure models also show increased propensity for diastolic Ca2+ release events which occur when sarcoplasmic reticulum Ca2+ content exceeds a certain threshold level. Such Ca2+ release events can initiate arrhythmias. In this study we aimed to investigate if both of these aspects of altered Ca2+ homeostasis could be found in left ventricular cardiomyocytes from rats with different states of cardiac function six weeks after myocardial infarction when compared to sham-operated controls. Video edge-detection, whole-cell Ca2+ imaging and confocal line-scan imaging were used to investigate cardiomyocyte contractile properties, Ca2+ transients and Ca2+ waves. In baseline conditions, i.e. without beta-adrenoceptor stimulation, cardiomyocytes from rats with large myocardial infarction, but without heart failure, did not differ from sham-operated animals in any of these aspects of cellular function. However, when exposed to beta-adrenoceptor stimulation, cardiomyocytes from both non-failing and failing rat hearts showed decreased sarcoplasmic reticulum Ca2+ content, decreased Ca2+ transient amplitude, and increased frequency of Ca2+ waves. These results are in line with a decreased threshold for diastolic Ca2+ release established by other studies. In the present study, factors that might contribute to a lower threshold for diastolic Ca2+ release were increased THR286 phosphorylation of Ca2+/calmodulin-dependent protein kinase II and increased protein phosphatase 1 abundance. In conclusion, this study demonstrates both decreased sarcoplasmic reticulum Ca2+ content and increased propensity for diastolic Ca2+ release events in ventricular cardiomyocytes from rats with heart failure after myocardial infarction, and that these phenomena are also found in rats with large myocardial infarctions without heart failure development. Importantly, beta-adrenoceptor stimulation is necessary to reveal these perturbations in Ca2+ handling after a myocardial infarction. 相似文献
958.
Differential proteome and cellular adhesion analyses of the probiotic bacterium Lactobacillus acidophilus NCFM grown on raffinose – an emerging prebiotic
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Hasan Ufuk Celebioglu Morten Ejby Avishek Majumder Carsten Købler Yong Jun Goh Kristian Thorsen Bjarne Schmidt Sarah O'Flaherty Maher Abou Hachem Sampo J. Lahtinen Susanne Jacobsen Todd R. Klaenhammer Susanne Brix Kristian Mølhave Birte Svensson 《Proteomics》2016,16(9):1361-1375
Whole cell and surface proteomes were analyzed together with adhesive properties of the probiotic bacterium Lactobacillus acidophilus NCFM (NCFM) grown on the emerging prebiotic raffinose, exemplifying a synbiotic. Adhesion of NCFM to mucin and intestinal HT‐29 cells increased three‐fold after culture with raffinose versus glucose, as also visualized by scanning electron microscopy. Comparative proteomics using 2D‐DIGE showed 43 unique proteins to change in relative abundance in whole cell lysates from NCFM grown on raffinose compared to glucose. Furthermore, 14 unique proteins in 18 spots of the surface subproteome underwent changes identified by differential 2DE, including elongation factor G, thermostable pullulanase, and phosphate starvation inducible stress‐related protein increasing in a range of +2.1 ? +4.7 fold. By contrast five known moonlighting proteins decreased in relative abundance by up to ?2.4 fold. Enzymes involved in raffinose catabolism were elevated in the whole cell proteome; α‐galactosidase (+13.9 fold); sucrose phosphorylase (+5.4 fold) together with metabolic enzymes from the Leloir pathway for galactose utilization and the glycolysis; β‐galactosidase (+5.7 fold); galactose (+2.9/+3.1 fold) and fructose (+2.8 fold) kinases. The insights at the molecular and cellular levels contributed to the understanding of the interplay of a synbiotic composed of NCFM and raffinose with the host. 相似文献
959.
Blanka Stiburkova Dana Gabrikova Pavel Čepek Pavel Šimek Pavol Kristian Elizabeth Cordoba-Lanus 《Nucleosides, nucleotides & nucleic acids》2016,35(10-12):529-535
ABSTRACTThe Roma represents a transnational ethnic group, with a current European population of 8–10 million. The evolutionary process that had the greatest impact on the gene pool of the Roma population is called the founder effect. Renal hypouricemia (RHUC) is a rare heterogenous inherited disorder characterized by impaired renal urate reabsorption. The affected individuals are predisposed to recurrent episodes of exercise-induced nonmyoglobinuric acute kidney injury and nephrolithiasis. To date, more than 150 patients with a loss-of-function mutation for the SLC22A12 (URAT1) gene have been found, most of whom are Asians. However, RHUC 1 patients have been described in a variety of ethnic groups (e.g., Arab Israelis, Iraqi Jews, Caucasians, and Roma) and in geographically noncontiguous countries. This study confirms our previous findings regarding the high frequency of SLC22A12 variants observed. Frequencies of the c.1245_1253del and c.1400C>T variants were found to be 1.92% and 5.56%, respectively, in a subgroup of the Roma population from five regions in three countries: Slovakia, Czech Republic, and Spain. Our findings suggested that the common dysfunction allelic variants of URAT1 exist in the general Roma population and thus renal hypouricemia should be kept in differential diagnostic algorithm on Roma patients with defect in renal tubular urate transport. This leads to confirm that the genetic drift in the Roma have increased the prevalence of hereditary disorders caused by very rare variants in major population. 相似文献
960.
Vincenzo Riso Marco Cammisa Harpreet Kukreja Zahra Anvar Gaetano Verde Angela Sparago Basilia Acurzio Shraddha Lad Enza Lonardo Aditya Sankar Kristian Helin Robert Feil Annalisa Fico Claudia Angelini Giovanna Grimaldi Andrea Riccio 《Nucleic acids research》2016,44(17):8165-8178
ZFP57 is necessary for maintaining repressive epigenetic modifications at Imprinting control regions (ICRs). In mouse embryonic stem cells (ESCs), ZFP57 binds ICRs (ICRBS) and many other loci (non-ICRBS). To address the role of ZFP57 on all its target sites, we performed high-throughput and multi-locus analyses of inbred and hybrid mouse ESC lines carrying different gene knockouts. By using an allele-specific RNA-seq approach, we demonstrate that ZFP57 loss results in derepression of the imprinted allele of multiple genes in the imprinted clusters. We also find marked epigenetic differences between ICRBS and non-ICRBS suggesting that different cis-acting regulatory functions are repressed by ZFP57 at these two classes of target loci. Overall, these data demonstrate that ZFP57 is pivotal to maintain the allele-specific epigenetic modifications of ICRs that in turn are necessary for maintaining the imprinted expression over long distances. At non-ICRBS, ZFP57 inactivation results in acquisition of epigenetic features that are characteristic of poised enhancers, suggesting that another function of ZFP57 in early embryogenesis is to repress cis-acting regulatory elements whose activity is not yet required. 相似文献