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81.
Mazurik VK Mikhaĭlov VF Ushenkova LN Nadezhina NM Raeva NF Nugis VIu Sevan'kaev AV Khvostunov IK Golub EV Mikhaĭlova GF Lloyd DC 《Radiatsionnaia biologiia, radioecologiia / Rossi?skaia akademiia nauk》2006,46(4):393-409
Molecular-biochemical and cytogenetic analyses were made on blood cells of 17 radiation accident victims who, from 1.7 to 43.8 years previously, had suffered acute radiation sickness (ARS) ranging from severity grades I to IV. Molecular-biochemical data were obtained with patients' leukocytes and with mononuclear cells on their oxidative status by a) the level of an anion-radical O2*- in the 3-(4,5-dimethyl-2-thiazol-2-yl)-2,5-diphenyl-2-tetrazolium bromide (MTT) test and b) the sum of reactive oxygen species in the 2,7-dichlorodihydrofluorescein diacetate (DCFDA) test together with a test for DNA strand unwinding in alkaline conditions by measurements of fluorescence intensity of ethidium bromide. Each parameter was measured in freshly sampled cells and during a 5-hour incubation as absolute means on 5 measurements and in % change from the initial values. Cytogenetic data were obtained from the standard metaphase preparations scored for routine unstable chromosomal aberrations (us-CA)--dicentrics; and stable aberrations (sCA)--translocations. The latter ones were assayed by the FISH method using whole chromosome 2, 4 and 12 fluorescent probes and scaled up to genome equivalence. For all patients reduced oxidative status of about 25-30% was obtained by the MTT-test (p < 0.005), and the DCFDA-test (p < 0.027). The yield of usCA depended on the time after irradiation with higher yields associated with the shorter postirradiation times and reducing almost to expected background frequencies. The yield of sCA was high for all patients, correlating with the severity of ARS whilst the molecular-biochemical parameters showed no relationship with ARS. A correlation was observed between parameters of oxidative status and % of cells with usCA: by the MTT-test r = from 0.50 up to 0.61 (p = from 0.06 up to 0.003), but by the DCFDA-test the strength of correlation was smaller: r = from 0.38 up to 0.48. An inverse correlation was found between initial oxidative state of mononuclear cells and the frequency of CA in lymphocytes. Similarly a marked inverse correlation between degree of DNA unwinding by the ethidium bromide assay on leukocytes and sCA in lymphocytes was also noted. The feasibility of radiation-induced delayed genomic instability in vivo for humans long time after irradiation is discussed. 相似文献
82.
Kovacević D Zarković-Palijan T Radeljak S Marinović D Hero ED Golub TL 《Collegium antropologicum》2010,34(Z2):29-37
The aim of the study was investigation of specific forensic aspects in offenders involved in domestic homicide cases in regard to sociodemographic and psychosocial variables and modalities of the offense. The research was conducted at the Department of Forensic Psychiatry in Neuropsychiatric Hospital "Dr. Ivan Barbot" in Popovaca, Croatia. The sample in this study consisted of domestic homicide group (N = 162). The results showed certain characteristics within the group of domestic homicide offenders. Generally speaking the offenders in domestic homicide cases were often married and were living in their families. Moreover, they were brought up in families with both parents and they had history of regular military service. Furthermore, offenders in domestic homicide cases were less involved in intervention from social services with rare history of home runaway and substance abuse during adolescence. Finally, the same group of offenders was less often had mothers or close friends with antisocial personality disorder but had frequent language and speech problems during adolescent period. In regard to the victims of domestic homicide they were often aged females. The offenders usually commit crime in their living space, either in the house or in the apartment. Based on these findings we conclude there are certain specific characteristics in the domestic homicide cases compared to homicide in general. 相似文献
83.
Kritsky MS Telegina TA Vechtomova YL Kolesnikov MP Lyudnikova TA Golub OA 《Biochemistry. Biokhimii?a》2010,75(10):1200-1216
Excited flavin and pterin molecules are active in intermolecular energy transfer and in photocatalysis of redox reactions
resulting in conservation of free energy. Flavin-containing pigments produced in models of the prebiotic environment are capable
of converting photon energy into the energy of phosphoanhydride bonds of ATP. However, during evolution photochemical reactions
involving excited FMN or FAD molecules failed to become participants of bioenergy transfer systems, but they appear in enzymes
responsible for repair of UV-damaged DNA (DNA photolyases) and also in receptors of blue and UV-A light regulating vital functions
of organisms. The families of these photoproteins (DNA-photolyases and cryptochromes, LOV-domain- and BLUF-domain-containing
proteins) are different in the structure and in mechanisms of the photoprocesses. The excited flavin molecules are involved
in photochemical processes in reaction centers of these photoproteins. In DNA photolyases and cryptochromes the excitation
energy on the reaction center flavin is supplied from an antenna molecule that is bound with the same polypeptide. The role
of antenna is played by MTHF or by 8-HDF in some DNA photolyases, i.e. also by molecules with known coenzyme functions in
biocatalysis. Differences in the structure of chromophore-binding domains suggest an independent origin of the photoprotein
families. The analysis of structure and properties of coenzyme molecules reveals some specific features that were significant
in evolution for their being selected as chromophores in these proteins. 相似文献
84.
85.
A mechanism of cyclin D1 action encoded in the patterns of gene expression in human cancer 总被引:33,自引:0,他引:33
Lamb J Ramaswamy S Ford HL Contreras B Martinez RV Kittrell FS Zahnow CA Patterson N Golub TR Ewen ME 《Cell》2003,114(3):323-334
86.
Nontemplate (N)-nucleotide addition by the terminal dideoxynucleotidyl transferase (TdT) at the junctions of rearranging V(D)J gene segments greatly contribute to antigen-receptor diversity. TdT has been identified in several vertebrate species, where it is highly conserved. We report here the isolation of two forms of TdT mRNA in an amphibian, the Mexican axolotl. The isoform TdT1 shares all of the conserved structural motifs required for TdT activity and displays an average of 50–58% similarity at the amino acid level with TdT of other species. The second axolotl TdT variant (TdT2) differs from TdT1 by a 57-amino acid deletion located between amino acids 165–222 of TdT1, including the first helix–hairpin–helix DNA-binding motif. During ontogeny, TdT products are first detected in the head of 6-week-old larvae and further in the head and trunk of 8-month-old larvae. These developmental stages correspond to the first detection of RAG1 and antigen-receptor (TCR and IgH) products in axolotl larvae. Our results suggest that in contrast to mammalian development, N diversity occurs early in axolotl development to diversify the primary repertoire. Phylogenetic analyses reveal that TdT and DNA polymerase (Pol ) genes are closely related, and that both enzymes were already present in the common ancestor of jawed vertebrates.This work is dedicated to the memory of Prof. Jacques CharlemagneThe sequences reported in this paper have been deposited in the GenBank database (accession numbers AF039209 and AY248700) 相似文献
87.
Gamma interferon triggers interaction between ICSBP (IRF-8) and TEL,recruiting the histone deacetylase HDAC3 to the interferon-responsive element 下载免费PDF全文
Kuwata T Gongora C Kanno Y Sakaguchi K Tamura T Kanno T Basrur V Martinez R Appella E Golub T Ozato K 《Molecular and cellular biology》2002,22(21):7439-7448
88.
Kirsch T Koyama E Liu M Golub EE Pacifici M 《The Journal of biological chemistry》2002,277(44):42171-42177
Chondrocyte proliferation is important for skeletal development and growth, but the mechanisms regulating it are not completely clear. Previously, we showed that syndecan-3, a cell surface heparan sulfate proteoglycan, is expressed by proliferating chondrocytes in vivo and that proliferation of cultured chondrocytes in vitro is sensitive to heparitinase treatment. To further establish the link between syndecan-3 and chondrocyte proliferation, additional studies were carried out in vivo and in vitro. We found that the topographical location of proliferating chondrocytes in developing chick long bones changes with increasing embryonic age and that syndecan-3 gene expression changes in a comparable manner. For in vitro analysis, mitotically quiescent chondrocytes were exposed to increasing amounts of fibroblast growth factor-2 (FGF-2). Proliferation was stimulated by as much as 8-10-fold within 24 h; strikingly, this stimulation was significantly prevented when the cells were treated with both fibroblast growth factor-2 (FGF-2) and antibodies against syndecan-3 core protein. This neutralizing effect was dose-dependent and elicited a maximum of 50-60% inhibition. To establish specificity of neutralizing effect, cultured chondrocytes were exposed to FGF-2, insulin-like growth factor-1, or parathyroid hormone, all known mitogens for chondrocytes. The syndecan-3 antibodies interfered only with FGF-2 mitogenic action, but not that of insulin-like growth factor-1 or parathyroid hormone. Protein cross-linking experiments indicated that syndecan-3 is present in monomeric, dimeric, and oligomeric forms on the chondrocyte surface. In addition, molecular modeling indicated that contiguous syndecan-3 molecules might form stable complexes by parallel pairing of beta-sheet segments within the ectodomain of the core protein. In conclusion, the results suggest that syndecan-3 is a direct and selective regulator of the mitotic behavior of chondrocytes and its role may involve formation of dimeric/oligomeric structures on their cell surface. 相似文献
89.
Golub AS Pittman RN 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2002,132(1):169-176
Work by previous investigators has indicated that a substantial amount of oxygen diffuses from the precapillary circulation. These losses imply that there should be radial gradients of oxygen tension (PO(2)) in arterioles, leading to a non-uniform distribution of oxygen within these microvessels. We have employed the phosphorescence quenching method to measure oxygen, allowing us to evaluate the heterogeneity of PO(2) inside short segments of microvessels. The phosphorescence decay curve contains information about the distribution of oxygen within the excited volume and the distribution can be represented as a histogram, by decomposing the decay curve into several components with weights proportional to the volume fraction of plasma with different PO(2), under the condition of a high signal-to-noise ratio. Furthermore, the histogram can be converted into a radial profile of PO(2), based on the assumptions of a circular vascular lumen, axisymmetric distribution of oxygen and monotonic PO(2) profile. Albumin-bound Pd-porphyrin phosphor was infused into the circulation of hamsters and excited by flash illumination at 10 Hz, with a square region of excitation light just covering the entire lumen, (i.e. width of region equaled luminal diameter) of microvessels in the hamster mesentery. A set of 50 curves (5 s of data) was averaged to obtain a decay curve with low noise. Curves were analyzed with the above histogram procedure, and this analysis allowed us to distinguish between PO(2) values originating from intra and extravascular subvolumes. The intravascular PO(2) in these microvessels was very heterogeneous, which could be explained by the existence of significant radial PO(2) gradients. The radial PO(2) gradients were estimated to be approximately 1 mmHg/microm. 相似文献
90.
Bcl2 regulation by the melanocyte master regulator Mitf modulates lineage survival and melanoma cell viability 总被引:25,自引:0,他引:25