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1.
Glenn C. Conroy 《International journal of primatology》1987,8(2):115-137
Body-weight estimates of fossil primates are commonly used to infer many important aspects of primate paleobiology, including
diet, ecology, and relative encephalization. It is important to examine carefully the methodologies and problems associated
with such estimates and the degree to which one can have confidence in them. New regression equations for predicting body
weight in fossil primates are given which provide body-weight estimates for most nonhominid primate species in the fossil
record. The consequences of using different subgroups (evolutionary “grades”) of primate species to estimate fossil-primate
body weights are explored and the implications of these results for interpreting the primate fossil record are discussed.
All species (fossil and extant) were separated into the following “grades”: prosimian grade, monkey grade, ape grade, anthropoid
grade, and all-primates grade. Regression equations relating lower molar size to body weight for each of these grades were
then calculated. In addition, a female-anthropoid grade regression was also calculated for predicting body weight infernales
of extinct, sexually dimorphic anthropoid species. These equations were then used to generate the fossil-primate body weights.
In many instances, the predicted fossil-primate body weights differ substantially from previous estimates. 相似文献
2.
The alpha 5 gene product assembles with multiple acetylcholine receptor subunits to form distinctive receptor subtypes in brain. 总被引:6,自引:0,他引:6
The acetylcholine receptor (AChR) alpha 5 gene has been classified as a member of the AChR gene family based on sequence homology. Expression studies, however, have yet to identify a function for the alpha 5 gene product or even to demonstrate an interaction with known AChR subunits. We report here that the alpha 5 gene product is identical to the 49 kd protein previously found on immunoblots of AChRs purified from brain and ciliary ganglia. In brain the alpha 5 gene product is present both in alpha 3- and in alpha 4-based receptor subtypes, while in the ganglion it is found in an alpha 3-based receptor subtype concentrated in postsynaptic membrane. Immunoprecipitation experiments with subunit-specific monoclonal antibodies indicate that some native AChRs are likely to have at least three kinds of subunits, with two being of the alpha type. These findings support new views about the construction of AChRs in neurons. 相似文献
3.
Molecular cloning of a GTPase activating protein specific for the Krev-1 protein p21rap1 总被引:29,自引:0,他引:29
B Rubinfeld S Munemitsu R Clark L Conroy K Watt W J Crosier F McCormick P Polakis 《Cell》1991,65(6):1033-1042
The rap1/Krev-1 gene encodes a ras-related protein that suppresses transformation by ras oncogenes. We have purified an 88 kd GTPase activating protein (GAP), specific for the rap1/Krev-1 gene product, from bovine brain. Based on partial amino acid sequences obtained from this protein, a 3.3 kb cDNA was isolated from a human brain library. Expression of the cDNA in insect Sf9 cells resulted in high level production of an 85-95 kd rap1GAP that specifically stimulated the GTPase activity of p21rap1. The complete deduced amino acid sequence is not homologous to any known protein sequences, including GAPs specific for p21ras. Northern and Western blotting analysis indicate that rap1GAP is not ubiquitously expressed and appears most abundant in fetal tissues and certain tumor cell lines, particularly the Wilms' kidney tumor, SK-NEP-1, and the melanoma, SK-MEL-3, cell lines. 相似文献
4.
Structure and evolution of teleost mitochondrial control regions 总被引:50,自引:0,他引:50
Woo-Jai Lee Janet Conroy W. Huntting Howell Thomas D. Kocher 《Journal of molecular evolution》1995,41(1):54-66
We amplified and sequenced the mitochondrial control region from 23 species representing six families of teleost fish. The length of this segment is highly variable among even closely related species due to the presence of tandemly repeated sequences and large insertions. The position of the repetitive sequences suggests that they arise during replication both near the origin of replication and at the site of termination of the D-loop strand. Many of the conserved sequence blocks (CSBs) observed in mammals are also found among fish. In particular, the mammalian CSB-D is present in all of the fish species studied. Study of potential secondary structures of RNAs from the conserved regions provides little insight into the functional constraints on these regions. The variable structure of these control regions suggests that particular care should be taken to identify the most appropriate segment for studies of intraspecific variation.
Correspondence to: T.D. Kocher 相似文献
5.
N J Wosu J A Shadduck S P Pakes J K Frenkel K S Todd J D Conroy 《Laboratory animal science》1977,27(2):210-216
The indirect immunofluorescence antibody test was performed on serial blood samples from eight young New Zealand White rabbits with experimental encephalitozoonosis. The test showed seroconversion in six of the eight infected rabbits by the 8th day after inoculation and in all rabbits by the 15th day. Antibody titers reached a peak by about the 36th day after inoculation and remained significantly elevated until the termination of the experiment at 84 days after inoculation. None of four sham-inoculated rabbits showed an immunofluorescence response by the 60th day after inoculation. Immunofluorescence and intradermal test responses were compared before infection and at the 60th day after inoculation in a total of 32 experimentally infected rabbits. Both tests were equally effective (100%) in detecting infected animals. Six of eight (first group) and 22 of 24 (second group) experimentally infected rabbits were confirmed histologically to have lesions compatible with encephalitozoonosis. No cross reactions were observed between Encephalitozoon cuniculi and Toxoplasma gondii, Eimeria perforans, or Eimeria stiedai by intradermal test or immunofluorescence test. 相似文献
6.
7.
The proton stoichiometry for the oxidation of cytochrome c peroxidase (ferrocytochrome c: hydrogen-peroxide oxidoreductase, EC 1.11.1.5) to cytochrome c peroxidase Compound I by H2O2, for the reduction of cytochrome c peroxidase Compound I to cytochrome c peroxidase Compound II by ferrocyanide, and for the reduction of cytochrome c peroxidase Compound II to the native enzyme by ferrocyanide has been determined as a function of pH between pH 4 and 8. The basic stoichiometry for the reaction is that no protons are required for the oxidation of the native enzyme to Compound I, while one proton is required for the reduction of Compound I to Compound II, and one proton is required for the reduction of Compound II to the native enzyme. Superimposed upon the basic stoichiometry is a contribution due to the perturbation of two ionizable groups in the enzyme by the redox reactions. The pKa values for the two groups are 4.9 +/- 0.3 and 5.7 +/- 0.2 in the native enzyme, 4.1 +/- 0.4 and 7.8 +/- 0.2 in Compound I, and 4.3 +/- 0.4 and 6.7 +/- 0.2 in Compound II. 相似文献
8.
9.
The activity of ornithine decarboxylase was investigated in cartilage from chick embryos, rabbits, rats and human foetuses. The enzyme activity in these cartilages was of the same order as the detected in other body tissues. Ornithine decarboxylase activity in chick-embryo cartilage and liver was the same when compared on the basis of total soluble tissue protein. The cartilage enzyme exhibited a pH optimum of 6.5 and a Km for ornithine of 0.16mM. Ornithine decarboxylase activity in chick-embryo pelvic leaflets was maintained at the value in vivo for up to 22h when the isolated tissue was incubated in a modified Waymouth's medium (MB 752/1) at 37 degrees C. After addition of cycloheximide to the incubation medium, ornithine decarboxylase activity declined, with a half-life of 40 min. The concentrations of the polyamines spermidine and spermine in chick-embryo pelvic cartilage and rabbit costal cartilage were of the same order as the concentrations detected in other tissues. 相似文献
10.
Jason S. Haukoos Jonathan D. Campbell Amy A. Conroy Emily Hopkins Meggan M. Bucossi Comilla Sasson Alia A. Al-Tayyib Mark W. Thrun For the Denver ED HIV Opt-Out Study Group 《PloS one》2013,8(12)