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81.
Molecular-genetic study of Pholidae of the suborder Zoarcoidei was first performed. Analysis of variation of genes of COI, cytochrome b, and 16S rRNA of mitochondrial DNA indicates different phylogenetic isolation of the family taxa. The groundlessness of separating subgenera (or genera) Enedrias and Allopholis and the rightfulness of including them in the composition of the genus Pholis are shown. Genetic close relation of the genera Pholis and Rhodymenichthys and their differences from the genus Apodichthys are established. The obtained results agree with the data of Makushok (1958) who separated in the composition of the family two subfamilies—Pholinae (with genera Pholis and Rhodymenichthys) and Apodichthyinae (with the genera Apodichthys, Xererpes, and Ulvicola). A key to species, genera, and subfamilies of gunnels of the northern part of the Pacific Ocean is provided.  相似文献   
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The effect of native α-fetoprotein (AFP) on the conversion of naïve T-helpers into central memory T-cells (TCM) and effector subpopulations of the preterminally differentiated (TEM) and terminally differentiated (TEMRA) memory T-cells was studied. AFP was found to prevent the conversion of naïve T-helpers into effector subpopulations of memory T cells (TEM and TEMRA) while reducing the total production of IL-4 and IFN-γ by the studied cell populations. The data reveal a new role of AFP in the immune tolerance formation during pregnancy.  相似文献   
84.
Analysis of sequence variation in the mitochondrial and nuclear genes in Azygopterus corallinus showed that this species was genetically close to the group uniting the representatives of the families Zoarcidae, Neozoarcidae, and Anarhichadidae. The considerable genetic differences between A. corallinus and the members of the family Stichaedae, to which it was assigned earlier, are consistent with the divergence estimates between the other families of the suborder Zoarcoidei (Zaproridae, Ptilichthyidae, Pholidae, Cryptacanthodidae, Bathymasteridae).  相似文献   
85.
A study of HIV-infected patients coinfected with hepatitis C virus and receiving antiretroviral therapy (ART) but not treated with interferon was performed. Patients were divided into two groups—with standard and inefficient recovery of CD4+ T cells. It was found that patients with discordant response of CD4+ T cells to ART showed heavier destructive processes in the liver than the successfully recovered subjects. They had increased levels of ALT and AST. In these patients, the risk of development of liver cirrhosis is greater.  相似文献   
86.
In general, optimal reaction norms in heterogeneous populations can be obtained only by iterative numerical procedures (McNamara, 1991; Kawecki and Stearns, 1993). We consider two particular, but biologically plausible and analytically tractable cases of individual optimization to gain insight into the mechanisms which shape the optimal reaction norm of fecundity in relation to an environmental variable or an individual trait. In the first case, we assume that the quality of the environment (e.g. food abundance) or the quality of the individual (e.g. body size) is fixed during its entire life; it may also be a heritable individual trait. In the second case, individual quality is assumed to change randomly such that the probability distribution of quality in the next year is the same for the parent and for her offspring. For these two cases, we obtain analytical expressions for the shape of the optimal reaction norm, which are heuristically interpretable in terms of underlying selective mechanisms. It is shown that better quality may reduce the optimal fecundity. This outcome is particularly likely if better quality increases a fecundity-independent factor of parental survival in a long-lived species with fixed quality. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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The mitochondrial COI gene was for the first time sequenced in eelpout species of the genus Zoarces from the Taui Bay of the Sea of Okhotsk: notched-fin Z. elongatus Kner, 1868 and the new sympatric form Zoarces sp., differing in a large set of morphological traits. The two species were compared with European eelpout Z. viviparus Linnaeus, 1758 from the Finnish Bay of the Baltic Sea. Divergence and phylogenetic analyses demonstrated a greater genetic similarity between Zoarces sp. and Z. viviparous than between sympatric Zoarces sp. and Z. elongatus.  相似文献   
89.
Analysis of the nucleotide sequences of mitochondrial and nuclear DNA genes was used to examine the relationships and position of the subfamily Xiphisterinae in the system of the suborder Zoarcoidei. This study showed the genetic heterogeneity of Xiphisterinae and the propriety of its division into two subfamilies: Xiphisterinae with the genera Xiphister and Phytichthys and Cebidichthyinae with the genera Cebidichthys, Dictyosoma, Esselenichthys, and Nivchia. The genetic differences between the two subfamilies were not less, but in some cases even greater than the differences between families within the suborder; therefore, they should be raised to the rank of a family, Xiphisteridae and Cebidichthyidae, and classified not within the superfamily Stichaeoidae but rather as independent taxa of the suborder Zoarcoidei.  相似文献   
90.
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