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941.
942.
A specific apoprotein activator for lipoprotein lipase 总被引:30,自引:0,他引:30
943.
The mechanism of the antitumor action of polyinosinic-polycytidylic acid is probably multifaceted. The compound induces the synthesis of interferon, and interferon probably is active against some tumors. Poly I:poly C alters protein and RNA synthesis in tissue culture. It specifically inhibits such macromolecule synthesis in tumors in vivo, while having less inhibitory action on synthesis in normal organs, or it may actually enhance. Finally, poly I:poly C strongly enhances graft vs. host rejection mechanisms, which may play a role in the rejection of some tumors. 相似文献
944.
Natural and acquired epidermal autoantibodies in man 总被引:1,自引:0,他引:1
C Ackermann-Schopf R Ackermann P I Terasaki J Levy 《Journal of immunology (Baltimore, Md. : 1950)》1974,112(6):2063-2067
945.
946.
Mutants of Escherichia coli have been selected for the absence of 5'-nucleotidase (uridine diphosphate-sugar hydrolase) and 3'-nucleotidase (2',3'-cyclic phophodiesterase). Mutants selected for the absence of 5'-nucleotidase are of two kinds: those that lack detectable activity for the enzyme (Ush(-)), and those that possess activity when cell extracts are assayed, but not when intact cells are assayed (cryptic; Crp(-)). The latter class is probably identical to a type of mutant previously reported by Ward and Glaser. When mutants are selected for the absence of 3'-nucleotidase, Crp(-)mutants are also obtained. Thus far, however, mutants totally lacking this enzyme have not been found. The location on the genetic map of one ush mutation is at position 11 min and that of one crp mutation at approximately 67 min. In the crp mutant, 5'-nucleotidase and 3'-nucleotidase remain located in the periplasm. This mutant is also cryptic for alkaline phosphatase but not for acid hexose phosphatase. Treatment of cells with ethylenediamine-tetraacetate substantially alleviated crypticity. These data are discussed in terms of the organization of periplasmic enzymes and of the outer membrane as a permeability barrier. 相似文献
947.
948.
Jack David Gordon Robert I. Levy Charles B. Perrow 《The Western journal of medicine》1958,89(6):397-399
Sixty acutely alcoholic patients were treated in unsegregated rooms of two to twelve beds in a general hospital to determine the feasibility of open ward care. Personnel caring for them were first educated in the nature of alcoholism, the aberrations it produces and treatment with tranquilizing drugs. Fears and objections were overcome.Violent or unpredictable patients were excluded from the test, but those with alcoholic hallucinations or delirium suspectible to control were admitted. Preliminary physical examination was done to find out whether there was coincidental disease. In three patients, one with subarachnoid hemorrhage, one with severe anemia and one with pneumonia and shock, this examination followed by prompt treatment was probably life-saving. Tranquilizers, fluids and vitamins were given routinely, by mouth as soon as possible.Alcoholic patients were found to be no more unmanageable than others.If it were generally accepted that acutely alcoholic patients, diagnosed as such, could be admitted to open ward care in general hospitals, candor in diagnosis would be encouraged thereby, coincident disease probably would be promptly recognized if present, and long-term treatment for the alcoholic addiction could be begun early. 相似文献
949.
950.
The protein kinase catalytic domain is one of the most abundant domains across all branches of life. Although kinases share a common core function of phosphoryl-transfer, they also have wide functional diversity and play varied roles in cell signaling networks, and for this reason are implicated in a number of human diseases. This functional diversity is primarily achieved through sequence variation, and uncovering the sequence-function relationships for the kinase family is a major challenge. In this study we use a statistical inference technique inspired by statistical physics, which builds a coevolutionary “Potts” Hamiltonian model of sequence variation in a protein family. We show how this model has sufficient power to predict the probability of specific subsequences in the highly diverged kinase family, which we verify by comparing the model’s predictions with experimental observations in the Uniprot database. We show that the pairwise (residue-residue) interaction terms of the statistical model are necessary and sufficient to capture higher-than-pairwise mutation patterns of natural kinase sequences. We observe that previously identified functional sets of residues have much stronger correlated interaction scores than are typical. 相似文献