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801.
Tom S. Smith Stephen Herrero Cali Strong Layton Randy T. Larsen Kathryn R. Johnson 《The Journal of wildlife management》2012,76(5):1021-1027
We compiled, summarized, and reviewed 269 incidents of bear–human conflict involving firearms that occurred in Alaska during 1883–2009. Encounters involving brown bears (Ursus arctos; 218 incidents, 81%), black bears (Ursus americanus; 30 incidents, 11%), polar bears (Ursus maritimus; 6 incidents, 2%), and 15 (6%) unidentified species provided insight into firearms success and failure. A total of 444 people and at least 367 bears were involved in these incidents. We found no significant difference in success rates (i.e., success being when the bear was stopped in its aggressive behavior) associated with long guns (76%) and handguns (84%). Moreover, firearm bearers suffered the same injury rates in close encounters with bears whether they used their firearms or not. Bears were killed in 61% (n = 162) of bear–firearms incidents. Additionally, we identified multiple reasons for firearms failing to stop an aggressive bear. Using logistic regression, the best model for predicting a successful outcome for firearm users included species and cohort of bear, human activity at time of encounter, whether or not the bear charged, and if fish or game meat was present. Firearm variables (e.g., type of gun, number of shots) were not useful in predicting outcomes in bear–firearms incidents. Although firearms have failed to protect some users, they are the only deterrent that can lethally stop an aggressive bear. Where firearms have failed to protect people, we identified contributing causes. Our findings suggest that only those proficient in firearms use should rely on them for protection in bear country. © 2012 The Wildlife Society. 相似文献
802.
803.
J. A. Kanis D. B. Horn R. D. M. Scott J. A. Strong 《BMJ (Clinical research ed.)》1974,3(5933):727-731
Thirteen patients with painful Paget''s disease of bone were treated as outpatients with low doses of synthetic salmon calcitonin 22·5-50 μg three times weekly. Treatment produced full remission of pain in a mean time of 5·5 weeks and a mean depression of serum alkaline phosphatase activity of 33%.The interval before symptomatic relief could not be predicted from the variables studied. The ultimate fall in serum alkaline phosphatase activity, however, could be predicted from the initial levels and from the early rate of decrease (P < 0·001). Biochemical resistance to treatment, which occurred in three cases, could be related to the dose and duration of treatment.Prolonged remissions of pain may occur which are not related to biochemical remission, to the dose of calcitonin, or to the duration of treatment. The side effects attributable to salmon calcitonin were transient nausea (in nine patients), transient flushing (in four), diarrhoea (in two), and rash (in one) though in only one patient did treatment have to be withdrawn prematurely because of these effects. 相似文献
804.
Summary An alkali soluble polymer was prepared from the metal tolerant alga Klebshormidium fluitans which had a recombining capacity of 0.41 mg Cu++/mg carbohydrate. Chemical preparation and properties, ion exchange behaviour, infra-red spectroscopy and acid hydrolysis indicate a polysaccharide containing uronic acid residues. 相似文献
805.
Amino acid sequence studies on the alpha chain of human fibrinogen. Exact location of cross-linking acceptor sites 总被引:2,自引:0,他引:2
Human fibrinogen was clotted under conditions that promote latent factor XIII activity and in the presence of a radioactive substitute cross-linking donor ([14C]glycine ethyl ester). The labeled fibrin was reduced and alkylated in the presence of 6 M guanidinium chloride. After dialysis and freeze-drying, the preparation was separated into its constituent polypeptide subunits by chromatography on (carboxymethyl)cellulose in the presence of 8 M urea. Under the incorporation conditions used, the radioactivity was limited to gamma chains (one donor molecule/chain) and alpha chains (two donor molecules/chain). The labeled alpha chains were digested with cyanogen bromide and fractionated on Sephadex G-50. All the radioactivity was found in a fragment previously designated H alpha CNI, the largest of the cyanogen bromide fragments in the alpha chain. The fragment was further fragmented by digestion with plasmin, trypsin, chymotrypsin, and/or staphylococcal protease. The incorporated radioactivity was found to reside in equal amounts at two different sites located 38 residues apart. These were determined to be positions 88 and 126 in H alpha CNI, which correspond to glutamine-328 and glutamine-366 in the alpha chain. 相似文献
806.
807.
808.
Michael J. Strong Ralph M. Garruto 《In vitro cellular & developmental biology. Plant》1989,25(10):939-945
Summary The spinal cords of fetal NIH∶CR mice, gestational age Day 12 to 14, were dissected free of meninges and dorsal root ganglia,
chemically dissociated, and layered onto discontinuous Percoll gradients at densities 1.040, 1.050, and 1.060 g/ml. After
centrifugation (800 Xg for 15 min at 4° C), three morphologically, biochemically, and immunohistologically distinct cell populations were collected
from the gradient interfaces. The first interface, located at a density of 1.040 g/ml, was choline acetyltransferase enriched
(0.86±0.08) compared to the second and third fractions (0.42±0.01 and 0 pmol acetylcholine synthesized/μg protein, respectively).
When simultaneously cultured with fetal mouse cardiac muscle on a gelatin-polylysine-laminin substrate in serum-free medium,
these cells developed the characteristics of motor neurons.
Dr. Strong is supported in part by a Research Fellowship from the Medical Research Council of Canada. 相似文献
809.
810.
Marcia R. Lee Richard E. Lee Jr. Janet M. Strong Stacey R. Minges John A. Mugnano 《Entomologia Experimentalis et Applicata》1998,89(2):103-109
The supercooling point (SCP) of an insect model, the lady beetle Hippodamia convergens Guérin-Menéville (Coleoptera, Coccinellidae) was markedly elevated by treatment with aqueous suspensions of the filamentous, ice nucleation active (INA) fungi Fusarium avenaceum and slightly elevated by Fusarium acuminatum. Addition of the surfactant Tween 80 to the fungal suspensions further reduced the supercooling capacity of adult beetles. When used alone the surfactant Triton X-100 produced a greater SCP elevation than Tween 20 or Tween 80. The emulsifier gum arabic was ineffective in elevating beetle SCPs when applied alone and when added to INA fungal preparations it decreased their efficacy. Aqueous suspensions of both viable sporulating and viable pleomorphic (a permanent, degenerative, nonsporulating cultural state) forms of both fungal species were more effective in elevating the SCP than killed preparations except for the pleomorphic F. acuminatum suspension in which the killed form was slightly more active. Application of INA fungi applied in combination with surfactants may be useful in the development of methods for the biological control of overwintering freeze-susceptible insect pests by decreasing their capacity to avoid lethal freezing by supercooling. 相似文献