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171.
Timothy HP Tan Timothy Barkham Burtram C Fielding Chih-Fong Chou Shuo Shen Seng Gee Lim Wanjin Hong Yee-Joo Tan 《Virology journal》2005,2(1):1-4
Phage N5 is one of the phages of Vibrio cholerae serovar O1 biotype El Tor (Ghosh, A. N., Ansari, M. Q., and Dutta, G. C. Isolation and morphological characterization of El Tor cholera phages. J. Gen. Virol. 70: 2241–2243, 1989). In the present communication the growth curve, molecular weight and confirmation of the genome, partial denaturation map and restriction endonuclease digestion pattern have been determined. Partial denaturation map indicates that the genome has non-permuted / invariant sequence. Presence of cohesive ends has also been documented. 相似文献
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ANDRÉ W. BREUKELAAR† EDDY H.R.R. LAMMENS‡ JAN G.P. KLEIN BRETELER§ ISTVAN TÁTRAI 《Freshwater Biology》1994,32(1):113-121
1. The effect of benthivorous bream and carp on sediment resuspension and the concentrations of nutrients and chlorophyll a were studied in sixteen experimental ponds (mean depth 1m, mean area 0.1 ha, sandy clay/clay sediment), stocked with bream or carp at densities varying from 0 to 500 kg ha?1. Planktivorous perch (Perca fluviatilis L.) were added to some ponds to suppress zooplankton. 2. Suspended sediment concentrations increased linearly with biomass of benthivorous fish. Bream caused an increase of 46 g sediment m?2 day?1 per 100kg bream ha?1 and a reduction of 0.38m?1 in reciprocal Secchi disc depth, corresponding to an increase in the extinction coefficient of 0.34m?1. 3. No relationship was found between size of fish and amount of resuspension, but the effect of bream was twice as great as that of carp. Benthivorous feeding was reduced in May because alternative food (zooplankton) was available. 4. Assuming a linear relationship, chlorophyll a level increased by 9.0 μgI?1, total P by 0.03mgl?1 and Kjeldahl-N by 0.48mgl?1 per 100kg bream ha?1. Silicate, chlorophyll a, total P and total N were all positively correlated with fish biomass, but orthophosphate showed no correlation. 相似文献
176.
Sang Jae SUH Heung Chul KIM Terry A. KLEIN Sung Tae CHONG Won Ja LEE Yong Jung KWON 《Entomological Research》2005,35(3):195-198
Tabanid flies were surveyed using New Jersey light traps and Mosquito Magnet® traps at US Army installations and training sites in the northern part of Gyeonggi Province, Republic of Korea. A total of 344 tabanid flies, comprising 14 species and 5 genera, were collected from June to August during 2003‐2004. Dominant species were Chrysops vanderwulpi (57.3%), Haematopota sinensis (29.1%), Haematopota koryoensis (4.4%) and Tabanus mandarinus (2.3%). Mosquito Magnet traps that generated CO2through the combustion of propane gas were nearly 6 times more effective in collecting tabanid flies than New Jersey light traps. Based on Mosquito Magnet trap collections, peak populations occurred from mid‐June to early July.; 相似文献
177.
Fusion of Tumour Cells with Host Cells 总被引:5,自引:0,他引:5
THE A9 cell is an 8-azaguanine-resistant derivative of the L cell line1. It lacks the enzyme inosinic acid pyrophosphorylase and is thus unable to grow in media such as HAT2 in which endogenous synthesis of nucleic acid is blocked by aminopterin. The A9 line has little ability to grow progressively in vivo. Inocula of 5 × 104 to 2 × 106 cells produced progressive tumours in only 12% of X-irradiated newborn syngeneic C3H mice3. One of these tumours was explanted as a cell suspension into Eagle's minimal essential medium containing 15% foetal calf serum and then subcultivated in this medium with 5% foetal calf serum. At each passage, cells were inoculated into X-irradiated newborn syngeneic C3H or semi-allogeneic C3H×X F1 mice (X designates a number of different allogeneic parents). Between 80 and 90% of the inoculated animals developed progressive tumours. The cell line was therefore designated A9HT (high take incidence). The karyotype of the A9HT line was found to be similar to that of the A9 line, but with a slightly reduced total chromosome number. The modal chromosome number of A9HT was about 53, compared with about 57 for A9 (see ref. 4). A9 and A9HT both had between 20 and 30 bi-armed chromosomes and a number of marker chromosomes in common. A detailed comparison of the karyotypes of the two lines examined by the quinacrine fluorescence technique has been made5. The A9HT line, like its A9 parent, lacks inosinic acid pyrophos-phorylase and is unable to grow in HAT medium. 相似文献
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179.
LAURA F. KLEIN 《American anthropologist》2007,109(2):421-422
The Politics of Egalitarianism: Theory and Practice . Jacqueline Solway, ed. New York: Berghahn, 2006. 260 pp. 相似文献
180.
Thirty-three dairy farms in the Norwegian counties of ?stfold and Akershus in which cubicle sheds had been in use for at least
one year and with a herd size of less than 60 cows, were contacted and asked to participate in a study. The study focused
on heifers' use of cubicles and concentrate dispenser just after being transferred from rearing accommodation to the milking
herd. For each heifer, the farmer recorded cubicle use once nightly between 9 and 11 pm. The daily amount of concentrate released
in the dispenser and the allotted daily ration were also recorded. The recording period was 15 consecutive days for cubicle
use and 7 days for concentrate dispenser use. Cubicle refusal behaviour, i.e. lying outside the cubicles, was analysed by
logistic regression using rearing accommodation of heifers, herd size, heifer age, and housing layout as independent variables,
and herd as a clustering variable. On Day 2 after transfer, 34% of the heifers were showing cubicle refusal behaviour (N =
340). By Day 15 this percentage had dropped to 23. Cubicle refusal was lower throughout the whole period among heifers which
used the cubicles on the 3 first days after transfer compared to those which did not. This tendency could also be detected
several months later. The analysis showed cubicle refusal to be significantly associated with rearing accommodation (OR =
6.1, c.i.95%OR = 1.5–24.3, P = 0.01) and cubicle layout in the shed (OR = 0.2, c.i.95%OR = 0.0–0.7, P = 0.01). None of the tested variables were found to be significant for failure to use the concentrate dispenser,
a behaviour which was less frequent than cubicle refusal. However, 8 percent of the heifers did not visit the dispenser at
all throughout the 7 days of observation. 相似文献