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51.
Mary Patterson 《The Australian journal of anthropology》2005,16(1):95-115
Although interest in cultural explanations of topics like incest waned among Anglo anthropologists along with the abandonment of kinship theory in general, other paradigms provided a renewed interest in some older theories about the prohibition of incest. The approach presented in this paper gives due critical consideration to both evolutionary and ‘cultural’ explanations of incest and its prohibition suggesting their mutual involvement, but the necessity of a close analysis of the specificity of the cultural forms in which shared substance, connection, difference and nurture are expressed as reproductive ontology. Particular cases are discussed in the light of recent suggestions that the cross‐cultural incidence of incest and its prohibition is to be understood via theories of dissociative disorders in the West that allegedly illuminate a wide range of practices claimed to be linked to sexual abuse in childhood. 相似文献
52.
Lau J Alberts AC Chemnick LG Gerber GP Jones KC Mitchell AA Ryder OA 《Molecular ecology resources》2009,9(5):1412-1414
Twenty-three polymorphic microsatellite markers were identified and characterized for Cyclura pinguis, a critically endangered species of lizard (Sauria: Iguanidae) native to Anegada Island in the British Virgin Islands. We examined variation at these loci for 39 C. pinguis, finding up to five alleles per locus and an average expected heterozygosity of 0.55. Allele frequency estimates for these microsatellite loci will be used to characterize genetic diversity of captive and wild C. pinguis populations and to estimate relatedness among adult iguanas at the San Diego Zoo that form the nucleus of a captive breeding programme for this critically endangered species. 相似文献
53.
Identification of a novel T cell surface disulfide-bonded dimer distinct from the alpha/beta antigen receptor 总被引:1,自引:0,他引:1
R Nagasawa J Gross O Kanagawa K Townsend L L Lanier J Chiller J P Allison 《Journal of immunology (Baltimore, Md. : 1950)》1987,138(3):815-824
Hybridomas were prepared from the spleen of a BALB/c mouse immunized with EL-4 T lymphoma cells. One, designated A1, was found to secrete a monoclonal antibody that reacted with two T lymphoma cells of C57BL origin, EL-4 and C6VLB, but not with normal C57BL/6 splenocytes or thymocytes, C57BL/6 T cell clones, or other T or B lymphomas by complement-mediated cytotoxicity or indirect immunofluorescent staining. Monoclonal antibody (MAb) A1 precipitated a protein that migrated at 85 kD under nonreducing and 43 kD under reducing conditions. The fact that the antigen defined by MAb A1 was a disulfide-linked dimer, together with the essentially clone-specific distribution of the reactive epitope, raised the possibility that the antibody defined an epitope of the antigen receptor. However, several additional observations revealed that the antibody defined a distinct and novel T cell surface structure. MAb 124-40, previously shown to react with the antigen receptor of C6VLB cells, reacted with variants of C6VLB that failed to express the A1 epitope. Sequential immunoprecipitation indicated that MAb A1 and MAb 124-40 reacted with distinct molecular species on C6VLB cells. Endoglycosidase digestion showed that the structure reactive with MAb A1 was not derived from that reactive with MAb 124-40 by addition of N-linked oligosaccharide residues. Two-dimensional gel electrophoretic analysis of precipitates obtained from radioiodinated C6VLB cells with MAb 124-40 resolved the alpha and beta subunits of the antigen receptor. Similar analysis of precipitates obtained with MAb A1 revealed only a single basic chain under reducing conditions, although anomalous mobility suggestive of a second, more acidic chain was observed under nonreducing conditions. Two-dimensional maps of tyrosine-containing chymotryptic peptides of the proteins isolated with MAb A1 and MAb 124-40 were completely different, suggesting that the molecules shared no peptides and were distinct in primary structure. Finally, cross-linking studies performed with a cleavable reagent indicated that the A1 molecule, unlike the antigen receptor defined with MAb 124-40, was not associated with additional, T3-like structures on the surface of C6VLB cells. Although the MAb A1 was unreactive with normal cells in cytotoxicity or staining assays, a molecule of the appropriate size was immunoprecipitated in small amounts from lysates of radioiodinated normal spleen and thymus cells. These data indicate that MAb A1 defines a novel disulfide-linked T cell surface molecule distinct from the antigen receptor. 相似文献
54.
Underiner TL Ruggeri B Aimone L Albom M Angeles T Chang H Hudkins RL Hunter K Josef K Robinson C Weinberg L Yang S Zulli A 《Bioorganic & medicinal chemistry letters》2008,18(7):2368-2372
Orally bioavailable, dual inhibitors of TIE-2/VEGF-R2 were identified by elaborating the C3/N13 SAR around a fused pyrrolodihydroindazolocarbazole scaffold. Analogs bearing a C3-thiophencarbonyl group were evaluated in enzymatic and cellular biochemical assays; two orally bioavailable analogs were further profiled in functional assays and found to inhibit microvessel growth in rat aortic explant cultures and inhibit Ang-1-stimulated chemotaxis of HUVECs. 相似文献
55.
Kozower BD Christofidou-Solomidou M Sweitzer TD Muro S Buerk DG Solomides CC Albelda SM Patterson GA Muzykantov VR 《Nature biotechnology》2003,21(4):392-398
Vascular immunotargeting may facilitate the rapid and specific delivery of therapeutic agents to endothelial cells. We investigated whether targeting of an antioxidant enzyme, catalase, to the pulmonary endothelium alleviates oxidative stress in an in vivo model of lung transplantation. Intravenously injected enzymes, conjugated with an antibody to platelet-endothelial cell adhesion molecule-1, accumulate in the pulmonary vasculature and retain their activity during prolonged cold storage and transplantation. Immunotargeting of catalase to donor rats augments the antioxidant capacity of the pulmonary endothelium, reduces oxidative stress, ameliorates ischemia-reperfusion injury, prolongs the acceptable cold ischemia period of lung grafts, and improves the function of transplanted lung grafts. These findings validate the therapeutic potential of vascular immunotargeting as a drug delivery strategy to reduce endothelial injury. Potential applications of this strategy include improving the outcome of clinical lung transplantation and treating a wide variety of endothelial disorders. 相似文献
56.
Diabetes and host resistance. I. Effect of alloxan diabetes upon the phagocytic and bactericidal efficiency of rat leukocytes for Pneumococcus 总被引:1,自引:0,他引:1
Briscoe, H. Frances (University Medical Center, Jackson, Miss.), and Fred Allison, Jr. Diabetes and host resistance. I. Effect of alloxan diabetes upon the phagocytic and bactericidal efficiency of rat leukocytes for pneumococcus. J. Bacteriol. 90:1537-1541. 1965.-Chronic diabetes mellitus was induced in rats with alloxan monohydrate. Glycosuria persisted for the 6 weeks of study, but ketonuria was never encountered. The cellular composition of peritoneal exudate recovered from diabetic rats after starch aleuronat administration was the same as that obtained from normal rats. The quantity of exudate recovered from the diabetic rats was thought to be less than that obtained from normal rats subjected to the same irritant. Phagocytosis was found to be essentially the same for both diabetic and normal cells when suspended in normal saline. The killing efficiency of harvested peritoneal phagocytes suspended in saline from both diabetic and normal rats for type 1 pneumococcus was compared and no difference between the groups was found. 相似文献
57.
The hereditary spastic paraplegias (HSPs) are genetic conditions in which there is progressive axonal degeneration in the corticospinal tract. Autosomal dominant mutations, including nonsense, frameshift and missense changes, in the gene encoding the microtubule severing ATPase spastin are the most common cause of HSP in North America and northern Europe. In this study we report quantitative gait analysis using a motorized treadmill system, carried out on mice knocked-in for a disease-associated mutation affecting a critical residue in the Walker A motif of the spastin ATPase domain. At 4 months and at one year of age homozygous mutant mice had a number of abnormal gait parameters, including in stride length and stride duration, compared to heterozygous and wild-type littermates. Gait parameters in heterozygous animals did not differ from wild-type littermates. We conclude that quantitative gait analysis using the DigiGait system sensitively detects motor abnormalities in a hereditary spastic paraplegia model, and would be a useful method for analyzing the effects of pharmacological treatments for HSP. 相似文献
58.
Patterson M. Wolfe A. K. Fleming P. A. Bateman P. W. Martin M. L. Sherratt E. Warburton N. M. 《Evolutionary ecology》2022,36(4):489-509
Evolutionary Ecology - As snakes are limbless, gape-limited predators, their skull is the main feeding structure involved in prey handling, manipulation and feeding. Ontogenetic changes in prey... 相似文献
59.
3-Deoxy-D-manno-octulosonate 8-phosphate synthase (KDO8PS) catalyzes the reaction between three-carbon phosphoenolpyruvate (PEP) and five-carbon d-arabinose 5-phosphate (A5P), generating KDO8P, a key intermediate in the biosynthetic pathway to 3-deoxy-D-manno-octulosonate, a component of the lipopolysaccharide of the Gram-negative bacterial cell wall. Both metal-dependent and metal-independent forms of KDO8PS have been characterized. KDO8PS is evolutionarily and mechanistically related to the first enzyme of the shikimate pathway, the obligately divalent metal ion-dependent 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase (DAH7PS) that couples PEP and four-carbon D-erythrose 4-phosphate (E4P) to give DAH7P. In KDO8PS, an absolutely conserved KANRS motif forms part of the A5P binding site, whereas in DAH7PS, an absolutely conserved KPR(S/T) motif accommodates E4P. Here, we have characterized four mutants of this motif (AANRS, KAARS, KARS, and KPRS) in metal-dependent KDO8PS from Acidithiobacillus ferrooxidans and metal-independent KDO8PS from Neisseria meningitidis to test the roles of the universal Lys and the Ala-Asn portion of the KANRS motif. The X-ray structures, determined for the N. meningitidis KDO8PS mutants, indicated no gross structural penalty resulting from mutation, but the subtle changes observed in the active sites of these mutant proteins correlated with their altered catalytic function. (1) The AANRS mutations destroyed catalytic activity. (2) The KAARS mutations lowered substrate selectivity, as well as activity. (3) Replacing KANRS with KARS or KPRS destroyed KDO8PS activity but did not produce a functional DAH7PS. Thus, Lys is critical to catalysis, and other changes are necessary to switch substrate specificity for both the metal-independent and metal-dependent forms of these enzymes. 相似文献
60.
S I Kuan J Stewart M K Dowd L Patterson J Dupont R C Seagrave 《Journal of lipid research》1992,33(11):1619-1628
Differences in dietary fats cause differences in cholesterol metabolism in mice. CBA/J mice are resistant to diet-induced hypercholesterolemia and atherosclerosis; they adjust hepatic hydroxymethyl-glutaryl-CoA reductase activity (HMGR) to maintain homeostasis; C57BR/cdJ mice are susceptible, but young animals are thought to maintain homeostasis by changing fecal excretion of sterols. Compartmental modelling of movement of [4-14C]cholesterol was used to analyze movement of cholesterol between serum and liver, heart, and carcass in mice fed 40 en% fat, polyunsaturated to saturated fatty acid ratio (P/S) = 0.24 (US74) or 30 en% fat, P/S = 1 (MOD). Dietary effects were quite pronounced, while strain effects were more subdued. The C57/cdJ animals appear to regulate the overall cholesterol balance by reducing synthesis, as do the CBA/J animals, even though synthesis is not reduced to the same degree as in the CBA/J animals. Both diet and strain influence the whole-animal turnover rate, with slower turnover occurring for C57BR/cdJ animals and animals fed the US74 diet. 相似文献