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131.
The poly(C) region affects progression of encephalomyocarditis virus infection in Langerhans' islets but not in the myocardium. 总被引:1,自引:0,他引:1
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The diabetogenic variant PV2 of encephalomyocarditis virus was cloned, and three recombinants differing in their 5' poly(C) tracts were analyzed. It is shown that the poly(C) region is not essential for infectivity in mice but does influence the virus load and degree of pathological lesions within the Langerhans' islets but not in the myocardium. 相似文献
132.
Use of biotinylated DNA probes in screening cells obtained from cervical swabs for human papillomavirus DNA sequences 总被引:1,自引:0,他引:1
R Neumann B Heiles C Zippel H J Eggers H H Zippel L Holzmann K D Schulz 《Acta cytologica》1986,30(6):603-607
A nonradioactive DNA-detection procedure using biotinylated DNA probes in the screening of cells from cervical swabs for DNA sequences homologous to human papillomavirus (HPV) DNA was tested. This alternative DNA-detection method yielded results comparable to those obtained with radioisotope-labeled DNA probes in 32 cases tested. This procedure obviates the special precautions required for radioisotope materials. Accordingly, this technique can be made available to many laboratories, and conclusive evidence as to the relation of HPV infection to cervical cancer may thus be accumulated. 相似文献
133.
The development of morbus haemolyticus neonatorum morbidity is demonstrated by referring to the example of the "exchange centre" in Rostock after using anti-D-immunprophylaxis for more than 10 years. The level achieved is compared with findings in international studies. The main cause for rest morbidity consists in omitting indicated immunoprophylaxis. Further progress in reducing the morbidity of morbus haemolyticus neonatorum can only be achieved by keeping physicians informed about the deleterious consequences of anti-D-immunisation having occurred. 相似文献
134.
Hemodynamic responses to oxygen breathing in man 总被引:1,自引:0,他引:1
135.
Eggers S Hashimoto DM Kirchengast S 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》2007,65(2):169-179
Infertility and sterility are worldwide phenomena with a long history. At a first glance a condition causing sterility seems to be paradox in an evolutionary sense because it contradicts the biogenetical imperative. In the present paper an evolutionary explanation for the high prevalence rate of PCOS, the most common endocrine disorder causing female infertility, is presented. The symptomatology of PCOS is described and the high prevalence rates of PCOS are explained by means of Darwinian medicine, kin selection and allomothering. 相似文献
136.
Diana Rubene Malin Leidefors Velemir Ninkovic Snke Eggers Matthew Low 《Ecology and evolution》2019,9(1):545-552
Foraging strategies of birds can influence trophic plant–insect networks with impacts on primary plant production. Recent experiments show that some forest insectivorous birds can use herbivore‐induced plant volatiles (HIPVs) to locate herbivore‐infested trees, but it is unclear how birds combine or prioritize visual and olfactory information when making foraging decisions. Here, we investigated attraction of ground‐foraging birds to HIPVs and visible prey in short vegetation on farmland in a series of foraging choice experiments. Birds showed an initial preference for HIPVs when visual information was the same for all choice options (i.e., one experimental setup had all options with visible prey, another setup with hidden prey). However, if the alternatives within an experimental setup included visible prey (without HIPV) in competition with HIPV‐only, then birds preferred the visual option over HIPVs. Our results show that olfactory cues can play an important role in birds’ foraging choices when visual information contains little variation; however, visual cues are preferred when variation is present. This suggests certain aspects of bird foraging decisions in agricultural habitats are mediated by olfactory interaction mechanisms between birds and plants. We also found that birds from variety of dietary food guilds were attracted to HIPVs; hence, the ability of birds to use plant cues is probably more general than previously thought, and may influence the biological pest control potential of birds on farmland. 相似文献
137.
M F Stock J Guerrero B Cobb C T Eggers T G Huang X Li D D Hackney 《The Journal of biological chemistry》1999,274(21):14617-14623
Full-length Drosophila kinesin heavy chain from position 1 to 975 was expressed in Escherichia coil (DKH975) and is a dimer. The sedimentation coefficient of DKH975 shifts from 5.4 S at 1 M NaCl to approximately 6.9 S at <0.2 M NaCl. This transition of DKH975 between extended and compact conformations is essentially identical to that for the heavy chain dimer of bovine kinesin (Hackney, D. D., Levitt, J. D., and Suhan, J. (1992) J. Biol. Chem. 267, 8696-8701). Thus the capacity for undergoing the 7 S/5 S transition is an intrinsic property of the heavy chains and requires neither light chains nor eukaryotic post-translational modification. DKH960 undergoes a similar transition, indicating that the extreme COOH-terminal region is not required. More extensive deletions from the COOH-terminal (DKH945 and DKH937) result in a shift in the midpoint for the transition to lower salt concentrations. DKH927 and shorter constructs remaining extended even in the absence of added salt. Thus the COOH-terminal approximately 50 amino acids are required for the formation of the compact conformation. Separately expressed COOH-terminal tail segments and NH2-terminal head/neck segments interact in a salt-dependent manner that is consistent with the compact conformer being produced by the interaction of domains from these regions of the heavy chain dimer. The microtubule-stimulated ATPase rate of DKH975 in the compact conformer is strongly inhibited compared with the rate of extended DKH894 (4 s-1 and 35 s-1, respectively, for kcat at saturating microtubules). 相似文献
138.
Direct detection of nucleic acid hybridization on the surface of a charge coupled device. 总被引:5,自引:4,他引:5
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J B Lamture K L Beattie B E Burke M D Eggers D J Ehrlich R Fowler M A Hollis B B Kosicki R K Reich S R Smith 《Nucleic acids research》1994,22(11):2121-2125
A method is described for the detection of DNA hybrids formed on a solid support, based upon the pairing of oligonucleotide chemistry and the technologies of electronic microdevice design. Surface matrices have been created in which oligonucleotide probes are covalently linked to a thin SiO2 film. 32P labeled target nucleic acid is then hybridized to this probe matrix under conditions of high stringency. The salient feature of the method is that to achieve the highest possible collection efficiency, the hybridization matrix is placed directly on the surface of a charge coupled device (CCD), which is used to detect 32P decay from hybridized target molecules (1, Eggers, M.D., Hogan, M.E., Reich, R.K., Lamture, J.B., Beattie, K.L., Hollis, M.A., Ehrilich, D.J., Kosicki, B.B., Shumaker, J.M., Varma, R.S., Burke, B.E., Murphy, A., and Rathman, D.D., (1993), Advances in DNA Sequencing Technology, Proc. SPIE, 1891, 13-26). Two implementations of the technology have been employed. The first involves direct attachment of the matrix to the surface of a CCD. The second involves attachment of the matrix to a disposible SiO2 coated chip, which is then placed face to face upon the CCD surface. As can be predicted from this favorable collection geometry and the known characteristics of a CCD, it is found that as measured by the time required to obtain equivalent signal to noise ratios, 32P detection speed by the direct CCD approach is at least 10 fold greater than can be obtained with a commercial gas phase array detector, and at least 100 fold greater than when X-ray film is used for 32P detection. Thus, it is shown that excellent quality hybridization signals can be obtained from a standard hybridization reaction, after only 1 second of CCD data acquisition. 相似文献
139.
Aiming at future comparisons with earlier hunter-gatherers or transitional populations, this paper intends to characterize and describe the oral pathology pattern of late agriculturalists from Central Andes dating to the Late Intermediate Period (LIP) and Inca periods (1000–1532 CE), and identify differences and/or similarities between coastal and highland populations. Although the botanical inventories of the LIP suggest carbohydrate-rich diets and similar components, it has been hypothesized that coastal and highland populations had, nevertheless, substantially different oral pathology patterns. We evaluated 14 indicators of oral pathology from Los Pinos (n = 200) and Armatambo (n = 25) sites in the Central Coast and two chronological phases from Laguna de los Cóndores site (LC-Inca, n = 23; and LC-LIP, n = 55), in the Peruvian northern highlands. The results showed a recurrent pattern of oral pathologies characterized by cervical caries (above 30%), extra-occlusal caries (above 60%), high rates of gross-gross caries, high frequency of ante mortem tooth loss, and signals of periodontal disease among these four populations. The diets of the coast were slightly more abrasive than those of the highlands. Oral pathology patterns were compatible with a slightly more cariogenic diet in the coast than in the highlands. In all four populations, those patterns were modulated by other common factors such as consumption of fermented drinks (maize beer – chicha) and the coca leaf chewing habit. 相似文献