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761.
Olfactory sexual inhibition and the westermarck effect 总被引:1,自引:0,他引:1
The Westermarck effect (sexual inhibition among individuals raised together) is argued to be mediated olfactorily. Various
animals, including humans, distinguish among individuals by scent (significantly determined by MHC genotype), and some avoid
cosocialized associates on this basis. Possible models of olfactory mechanisms in humans are evaluated. Evidence suggests
aversions develop during an early sensitizing period, attach to persons as much as to their scents, and are more powerful
among females than among males. Adult to child aversions may develop similarly, but more likely result from stimulus generalization.
This hypothesis accords with current evidence and yields testable predictions (e.g., anosmia will prevent inhibition) that,
should they be supported, will conclusively ground the Westermarck effect in a biological mechanism.
A version of this paper was originally presented at the 92nd annual meeting of the American Sociological Association in Toronto,
Canada.
Mark A. Schneider is a sociologist of science and author of “Sacredness, Status and Bodily Violation” (Body and Society, 1996) as well as Culture and Enchantment (Chicago, 1993). Lewellyn Hendrix has written extensively on families in cross-cultural perspective and is the author of
Illegitimacy and Social Structures (Bergin and Garvey, 1996). They recently coauthored “Assumptions on Sex and Society in the Biosocial Theory of Incest” (Cross-Cultural Research, 1999). 相似文献
762.
763.
764.
765.
Douglas F. Antczak 《Animal genetics》1984,15(2):103-115
A new polymorphic locus of the horse which has several unusual properties is described. The suggested name for the locus is ELY-2 . The gene product of one allele at this locus, designated ELY-2.1 , has been identified with antisera raised as a result of pregnancy. Antibody to ELY-2.1 was first detected on day 55 after conception in the serum of a mare in first pregnancy. This early onset of antibody is similar to that seen for antibody to ELA antigens, and suggests that the source of the antigenic stimulus may be the tissue of the equine endometrial cups.
The antisera identifying ELY-2.1 are cytotoxic and kill all peripheral blood lymphocytes from horses carrying the antigen. ELY-2.1 is a cell surface molecule expressed on lymphocytes, erythrocytes, and platelets. Other cell types have not been investigated. The overall phenotypic frequency of ELY-2.1 in several horse breeds was 16 %. The ELY-2.1 antigen is controlled by an autosomal, dominant gene which is not coded by the ELA region (the major histocompatibility complex of the horse), nor is it identical to the ELY-1 locus, which codes for another cell surface alloantigen of equine lymphocytes. Stimulator cells carrying ELY-2.1 did not induce proliferation of ELY-2.1 negative responder cells in mixed cultures of horse lymphocytes. Attempts to raise alloantisera to other alleles of the ELY-2 locus through immunization with lymphocytes were unsuccessful. It is possible that the alternate allele(s) does not code for a gene product which is expressed. The function and biochemical nature of the ELY-2.1 molecule are unknown. 相似文献
The antisera identifying ELY-2.1 are cytotoxic and kill all peripheral blood lymphocytes from horses carrying the antigen. ELY-2.1 is a cell surface molecule expressed on lymphocytes, erythrocytes, and platelets. Other cell types have not been investigated. The overall phenotypic frequency of ELY-2.1 in several horse breeds was 16 %. The ELY-2.1 antigen is controlled by an autosomal, dominant gene which is not coded by the ELA region (the major histocompatibility complex of the horse), nor is it identical to the ELY-1 locus, which codes for another cell surface alloantigen of equine lymphocytes. Stimulator cells carrying ELY-2.1 did not induce proliferation of ELY-2.1 negative responder cells in mixed cultures of horse lymphocytes. Attempts to raise alloantisera to other alleles of the ELY-2 locus through immunization with lymphocytes were unsuccessful. It is possible that the alternate allele(s) does not code for a gene product which is expressed. The function and biochemical nature of the ELY-2.1 molecule are unknown. 相似文献
766.
Summary Two tissue culture incubation systems are described in which immune responses to cell surface antigens have been demonstrated
In the one-way “mixed lymphocyte interaction” system, a specific stimulation of thymidine uptake was induced by a particulate
membrane antigen fraction, the microsomal lipoproteins (MLP)when low levels (0.01 to 0.001 μg per ml) were incubated with
spleen or lymph node cells from nonsensitized mice. No stimulation was seen when allogeneic MLP was used at high levels, 10
μg per ml, nor at any level with syngeneic MLP. Specific effectors were demonstrated after 72-hr incubation with stimulatory
levels of allogeneic MLP in three separate in vitro assays, a plaque-forming cell reduction assay, a tumor target assay, and
an antigen-binding cell assay. In the latter assay, [125I]MLP was used as the source of antigen. This system has limited potential inasmuch as mouse spleen cells do not survive in
it beyond the 4th day of culture. The second tissue culture system, the Marbrook system, has much greater possibilities because
at least 25% of the inoculum is recovered 7days later. In this culture system a cell-free sheep erythrocyte membrane preparation
can induce, plaque-forming cells in the absence of macrophages. Using a sensitive radioimmunoassay, frees specific antibody
was detected in culture supernatant fluids. With the same culture system, allogeneic lymphocytotoxic cells (killer) have been
induced with spleen cells from unprimed mice in strains differing at the major histocompatibility locus (H-2). Allogeneic
MLP induced very significant “killer” cell activity with spleen cells from primed mice. In a syngeneic tumor systems, significant
amounts of killer cell activity were induced with unprimed spleen cell inocula, and much larger amounts induced with spleen
cells from immunized mice.
Presented in the formal symposium on Carcinogenesis in Vitro, at the 25th Annual Meeting of the Tissue Culture Association,
Miami Beach, Florida, June 3–6, 1974.
This work was supported by Public Health Service Rescarch grants CA 07973 and CA 10815 from the National Cancer Institute. 相似文献
767.
Altogether, 292 goat alloantisera were screened for antilymphocyte reactivity in a two-step dye exclusion microcytotoxicity test. Fifteen different lymphocyte antigen specificities were characterized by cluster analysis and absorption studies. The specificities were designated N1-N15 (N for Norwegian). Lymphocytes from 247 Norwegian dairy goats were tested. Each animal displayed from none to four of the characterized specificities. Lysostrip testing and family studies indicated that the specificities N1-N14 were coded for by multiple alleles belonging to at least two closely linked loci. It is suggested that these loci are part of the caprine major histocompatibility complex. Family studies gave strong evidence that the specificity N15 was not coded for by genes located in the same region as the other 14 specificities. Absorption studies showed that this specificity was located on both lymphocytes and erythrocytes. 相似文献
768.
769.
Xiaowei Jiang Mario A. Fares 《Evolution; international journal of organic evolution》2010,64(5):1429-1445
The antigenic peptide, major histocompatibility complex molecule (MHC; also called human leukocyte antigen, HLA), coreceptor CD8, or CD4 and T‐cell receptor (TCR) function as a complex to initiate effectors’ mechanisms of the immune system. The tight functional and physical interaction among these molecules may have involved strong coevolution links among domains within and between proteins. Despite the importance of unraveling such dependencies to understand the arms race of host–pathogen interaction, no previous studies have aimed at achieving such an objective. Here, we perform an exhaustive coevolution analysis and show that indeed such dependencies are strongly shaping the evolution and probably the function of these molecules. We identify intramolecular coevolution in HLA class I and II at domains important for their immune activity. Most of the amino acid sites identified to be coevolving in HLAI have been also detected to undergo positive Darwinian selection highlighting therefore their adaptive value. We also identify coevolution among antigen‐binding pockets (P1‐P9) and among these and TCR‐binding sites. Conversely to HLAI, coevolution is weaker in HLAII. Our results support that such coevolutionary patterns are due to selective pressures of host–pathogen coevolution and cooperative binding of TCRs, antigenic peptides, and CD8/CD4 to HLAI and HLAII. 相似文献
770.
K. Liu P. Zhang J. Gao H. Liu G. Li Z. Qiu Y. Zhang J. Ren P. Tan R. Z. Ma 《Animal genetics》2011,42(2):204-207
A 184 kb gap in an ovine MHC physical map was successfully closed by identification of two overlapping clones (304C7 and 222G18) from a Chinese fine wool merino sheep BAC library. The location and tiling path of the two clones were confirmed by BAC‐end sequencing and PCR amplification of loci in overlapping regions. Full‐length sequencing of the clones identified 13 novel ovine genes in the gap between loci Notch4 and Btnl2, and eight of them belonging to the Butyrophilin‐like (Btn‐like or Btnl) gene family. The scattered distribution of the Btnl gene cluster at the gap provided a clue to explain the difficulties previously experienced in closing the gap. Completed BAC contigs of the ovine MHC will facilitate sequencing of the entire ovine leukocyte antigen (OLA) region, providing detailed information for comparative studies of MHC evolution. 相似文献