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41.
Josef ?pak Ivan Votruba Daniela Pavingerová Antonín Holy Vlastimila ?paková Karel Petrzik 《Plant Cell, Tissue and Organ Culture》2012,110(1):63-68
Antiviral effects of acyclic nucleoside phosphonates PMEA, (S)-HPMPC, PMEDAP, and ribavirin on double-stranded DNA Cauliflower mosaic virus (CaMV) were evaluated in Brassica pekinensis plants grown in vitro on liquid medium. A double-antibody sandwich ELISA was used for relative quantification of viral protein and PCR for detection of CaMV nucleic acid in plants. Ribavirin and PMEA had no significant antiviral effect. (S)-HPMPC at concentration 50?mg?l?1 and PMEDAP at concentrations 50 and 12.5?mg?l?1 significantly (P?<?0.05) reduced CaMV concentration in plants within 42?C63?days to levels detectable neither by ELISA nor by PCR. A phytotoxicity experiment resulted in progressive yellowing of leaves and dwarfing in plants cultured 42?days on media with concentrations 12.5, 25 and 50?mg?l?1 of (S)-HPMPC and PMEDAP. Reduction in fresh and dry weights of plants was significant (P?<?0.05) already at 12.5?mg?l?1 with both compounds. 相似文献
42.
D. Reymen L. Naesens J. Balzarini A. Holy E. De Clercq 《Nucleosides, nucleotides & nucleic acids》2013,32(3-5):567-570
Abstract HHV-6 was evaluated in vitro for its susceptibility to a broad range of nucleoside analogues. PFA and several acyclic nucleoside phophonates emerged as the most potent inhibitors of HHV-6 replication as monitored by a newly developed immunofluorescence / flow cytometric assay as well as by microscopical evaluation of their inhibitory effect on HHV-6-induced cytopathogenicity. 相似文献
43.
Aim
Many important patterns and processes vary across the phylogeny and depend on phylogenetic scale. Nonetheless, phylogenetic scale has never been formally conceptualized, and its potential remains largely unexplored. Here, we formalize the concept of phylogenetic scale, review how phylogenetic scale has been considered across multiple fields and provide practical guidelines for the use of phylogenetic scale to address a range of biological questions.Innovation
We summarize how phylogenetic scale has been treated in macroevolution, community ecology, biogeography and macroecology, illustrating how it can inform, and possibly resolve, some of the longstanding controversies in these fields. To promote the concept empirically, we define phylogenetic grain and extent, scale dependence, scaling and the domains of phylogenetic scale. We illustrate how existing phylogenetic data and statistical tools can be used to investigate the effects of scale on a variety of well‐known patterns and processes, including diversification rates, community structure, niche conservatism or species‐abundance distributions.Main conclusions
Explicit consideration of phylogenetic scale can provide new and more complete insight into many longstanding questions across multiple fields (macroevolution, community ecology, biogeography and macroecology). Building on the existing resources and isolated efforts across fields, future research centred on phylogenetic scale might enrich our understanding of the processes that together, but over different scales, shape the diversity of life. 相似文献44.
Avril J. Swarts John W. Hastings Robert F. Roberts Alexander von Holy 《Current microbiology》1998,36(5):266-270
Flow cytometry was used to study the effect of the bacteriocin leucocin B-TA11a on Listeria (L.) monocytogenes. Mixed proportions of dead and live control populations were analyzed by flow cytometry to determine detection limits of
the Dead/Live Baclight Bacterial Viability KitTM. High correlations for flow cytometric detection of defined proportions of live or dead cells in mixtures between 10 and
100% of dead (r2 = 0.97) or live (r2 = 0.99) cells were obtained. However, mixtures containing less than 10% of either live or dead control cells gave correlations
below 0.72. The growth of L. monocytogenes in the absence and presence of leucocin B-TA11a was analyzed by flow cytometry with Baclight, plate counts, and optical density measurements. Although leucocin B-TA11a initially inhibited listerial growth, the
uptake of both Baclight dyes suggested that cells remained viable but became leaky, possibly indicating bacteriocin-induced pore formation in
the target membranes.
Received: 30 June 1997 / Accepted: 20 October 1997 相似文献
45.
D Fasshauer W Antonin M Margittai S Pabst R Jahn 《The Journal of biological chemistry》1999,274(22):15440-15446
Assembly of soluble N-ethylmaleimide-sensitive fusion attachment protein receptor (SNARE) proteins between two opposing membranes is thought to be the key event that initiates membrane fusion. Many new SNARE proteins have recently been localized to distinct intracellular compartments, supporting the view that sets of specific SNAREs are specialized for distinct trafficking steps. We have now investigated whether other SNAREs can form complexes with components of the synaptic SNARE complex including synaptobrevin/VAMP 2, SNAP-25, and syntaxin 1. When the Q-SNAREs syntaxin 2, 3, and 4, and the R-SNARE endobrevin/VAMP 8 were used in various combinations, heat-resistant complexes were formed. Limited proteolysis revealed that these complexes contained a protease-resistant core similar to that of the synaptic complex. All complexes were disassembled by the ATPase N-ethylmaleimide-sensitive fusion protein and its cofactor alpha-SNAP. Circular dichroism spectroscopy showed that major conformational changes occur during assembly, which are associated with induction of structure from unstructured monomers. Furthermore, no preference for synaptobrevin was observed during the assembly of the synaptic complex when endobrevin/VAMP 8 was present in equal concentrations. We conclude that cognate and non-cognate SNARE complexes are very similar with respect to biophysical properties, assembly, and disassembly, suggesting that specificity of membrane fusion in intracellular membrane traffic is not due to intrinsic specificity of SNARE pairing. 相似文献
46.
Kotik Michael Vanacek Pavel Kunka Antonin Prokop Zbynek Damborsky Jiri 《Applied microbiology and biotechnology》2017,101(16):6385-6397
Applied Microbiology and Biotechnology - Haloalkane dehalogenases (HLDs) are environmentally relevant enzymes cleaving a carbon-halogen bond in a wide range of halogenated pollutants. PCR with... 相似文献
47.
Korenek A Prochazka M 《Biomedical papers of the Medical Faculty of the University Palacky, Olomouc, Czechoslovakia》2008,152(1):97-99
Aims: To evaluate the iodine status of patients in early pregnancy and its dependence on level of thyroid-stimulating hormone (TSH). Methods: Between June 2005 and December 2006, 168 patients with a confirmed vital pregnancy (up to 10(th) week of pregnancy) were included in the study. The entry criteria were no prior thyroid disease, did not take any other medication, had not undergone radio-iodine therapy and did not take multivitamins containing iodine. The iodine status was measured as the amount of iodine in urine over 24 hours. The TSH level was determined from the blood using chemiluminescence. Results: The average ioduria value in patients was found to be 3.04 micromol/24 hr, with the norm 0.6-2.4 micromol/ 24 hr, median 2.9, SD 1.5. None of the patients had a value lower than 0.9 micromol/24 hr. The average TSH value was 1.98 mIU/l, median was 1.31, SD 0.98. The laboratory limits were set to 0.25-3 mIU/l for pregnant women in the first trimester. Three pregnancies ended in miscarriage by week 12, 1 miscarriage occurred in week 22 and the other pregnancies concluded in delivery between weeks 38-41. Fourteen patients had TSH levels above 3 mIU/l with normal levels od free thyroxine (T4) : 10.3-25 pmol/l. Conclusions: The results of this study did not reveal any iodine deficit in any of the patients. However 14 patients had elevated TSH levels signalling subclinical or incipiently clinical hypothyroidism. These pacients underwent levothyroxine therapy after endocrinologist's consultations. 相似文献
48.
Pelech S Jelinkova L Susor A Zhang H Shi X Pavlok A Kubelka M Kovarova H 《Journal of proteome research》2008,7(7):2860-2871
Kinex antibody microarray analyses was used to investigate the regulation of 188 protein kinases, 24 protein phosphatases, and 170 other regulatory proteins during meiotic maturation of immature germinal vesicle (GV+) pig oocytes to maturing oocytes that had completed meiosis I (MI), and fully mature oocytes arrested at metaphase of meiosis II (MII). Increases in apparent protein levels of protein kinases accounted for most of the detected changes during the GV to MI transition, whereas reduced protein kinase levels and increased protein phosphorylation characterized the MI to MII transition. During the MI to MII period, many of the MI-associated increased levels of the proteins and phosphosites were completely or partially reversed. The regulation of these proteins were also examined in parallel during the meiotic maturation of bovine, frog, and sea star oocytes with the Kinex antibody microarray. Western blotting analyses confirmed altered expression levels of Bub1A, IRAK4, MST2, PP4C, and Rsk2, and the phosphorylation site changes in the kinases Erk5 (T218 + Y220), FAK (S722), GSK3-beta (Y216), MEK1 (S217 + S221) and PKR1 (T451), and nucleophosmin/B23 (S4) during pig oocyte maturation. 相似文献
49.
Antonin Bukovsky Korakod Indrapichate Hiroshi Fujiwara Maria Cekanova Maria E Ayala Roberto Dominguez Michael R Caudle Jay Wimalsena Robert F Elder Pleas Copas James S Foster Romaine I Fernando Donald C Henley Nirmala B Upadhyaya 《Reproductive biology and endocrinology : RB&E》2003,1(1):1-18
Distinct luteinizing hormone receptor (LHR) protein variants exist due to the posttranslational modifications. Besides ovaries, LHR immunoreactivity (LHRI) was also found in other tissues, such as the brain, fallopian tube, endometrium, trophoblast and resident tissue macrophages. The 3B5 mouse monoclonal antibody was raised against purified rat LHR. In rat, porcine and human ovaries, the 3B5 identified six distinct LHR bands migrating at ~92, 80, 68, 59, 52 and 48 kDa. Characteristic LHRI was detected in rat, human and porcine corpora lutea. During cellular differentiation, subcellular LHR distribution changed from none to granular cytoplasmic, perinuclear, surface, nuclear and no staining. There were also differences in vascular LHR expression – lack of LHRI in ovarian vessels and strong staining of vessels in other tissues investigated. In normal human term placentae, villous LHRI was associated with blood sinusoids and cytotrophoblast cells, and rarely detected in trophoblastic syncytium. In all abnormal placentae, the LHRI of sinusoids was absent, and syncytium showed either enhanced (immature placental phenotypes) or no LHRI (aged placental phenotype). LHRI in human brain was identified in microglial cells (CD68+ resident macrophages). Protein extracts from human vaginal wall and levator ani muscle and fascia showed strong ~92 and 68 kDa species, and LHRI was detected in smooth muscle cells, fibroblasts, resident macrophages and nuclei of skeletal muscle fibers. Our observations indicate that, in contrast to the theory on the role of vascular hormone receptors in preferential pick up of circulating hormones, there is no need to enhance selective pick up rather only prevent LH/CG transport to inappropriate sites. Abnormal placental LHR expression may play a role in the development of abnormal pregnancy. Expression of LHR in the pelvic floor compartments suggests that high LH levels in postmenopausal women may contribute to the pelvic floor relaxation and increased incidence of pelvic floor disorders. Since chorionic gonadotropin increases secretion of a variety of cytokines by monocytes, and induces their inflammatory reaction and phagocytic activity, high LH levels in aging individuals may also activate microglia (mononuclear phagocyte system in the central nervous system) and contribute to the development of Alzheimer's disease and other inflammation-mediated neurodegenerative diseases. 相似文献
50.
Antonin Bukovsky 《World journal of stem cells》2015,7(8):1109-1117
Endogenous “stem cell niche” (SCN) accompanying vessels contains immune system components which in vivo determine differentiation of multi potent stem cells toward proper cell types in given tissue. Combinations of sex steroids may represent novel chemical approach for neuronal areas of regenerative medicine, since they cause transformation of vascular smooth muscle stem cells into differentiating neuronal cells. Circulating sex steroids are present during pregnancy and can be utilized where needed, when various embryonic/fetal tissues develop from their stem cells. Utilization of induced regeneration of tissues (regenerative medicine) is expected being more effective in sudden failures of younger individuals carrying intact SCN, as compared to established chronic disorders caused by SCN alteration. An essential component of SCN are monocyte-derived cells exhibiting tissue-specific “stop effect” (SE) preventing, for instance, an aging of neuronal cells. Its alteration causes that implantation of neuronal stem cells will also result in their differentiation toward aging cells. When we repair the SE by supply of circulating mononuclear cells from young healthy individuals, we may be able to provide novel regenerative treatments of age-induced neural diseases by sex steroid combinations. Questions regarding some age-induced body alterations are also addressed. 相似文献