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排序方式: 共有249条查询结果,搜索用时 15 毫秒
31.
Marchès O Batchelor M Shaw RK Patel A Cummings N Nagai T Sasakawa C Carlsson SR Lundmark R Cougoule C Caron E Knutton S Connerton I Frankel G 《Journal of bacteriology》2006,188(8):3110-3115
EspF of enteropathogenic Escherichia coli targets mitochondria and subverts a number of cellular functions. EspF consists of six putative Src homology 3 (SH3) domain binding motifs. In this study we identified sorting nexin 9 (SNX9) as a host cell EspF binding partner protein, which binds EspF via its amino-terminal SH3 region. Coimmunoprecipitation and confocal microscopy showed specific EspF-SNX9 interaction and non-mitochondrial protein colocalization in infected epithelial cells. 相似文献
32.
QTL detection experiments in livestock species commonly use the half-sib design. Each male is mated to a number of females, each female producing a limited number of progeny. Analysis consists of attempting to detect associations between phenotype and genotype measured on the progeny. When family sizes are limiting experimenters may wish to incorporate as much information as possible into a single analysis. However, combining information across sires is problematic because of incomplete linkage disequilibrium between the markers and the QTL in the population. This study describes formulæ for obtaining MLEs via the expectation maximization (EM) algorithm for use in a multiple-trait, multiple-family analysis. A model specifying a QTL with only two alleles, and a common within sire error variance is assumed. Compared to single-family analyses, power can be improved up to fourfold with multi-family analyses. The accuracy and precision of QTL location estimates are also substantially improved. With small family sizes, the multi-family, multi-trait analyses reduce substantially, but not totally remove, biases in QTL effect estimates. In situations where multiple QTL alleles are segregating the multi-family analysis will average out the effects of the different QTL alleles. 相似文献
33.
Six non-pregnant cows were allocated into 3 groups. Group 1 comprised a pair of lactating cows, whereas groups 2 and 3 each comprised a pair of non-lactating cows. The cows in groups 1 and 2 were dosed intraruminally by stomach tube with zinc oxide at 120 mg Zn per kg of bodyweight at weekly intervals for a period of 33 days. Each cow received a total of 4 doses of zinc oxide. Group 3 served as non-treated control group. Blood samples were collected from all 6 cows daily. Serum was analysed for concentration of calcium. Within 12–24 h of each zinc oxide administration the serum calcium of the lactating cows dropped dramatically indicating the existence of an antagonistic effect between Zn and Ca. The first Zn induced hypocalcaemic episode in the lactating cows was followed by a rise in serum calcium to a level above the pre-dosing level and above the mean value of the control group. The depth of the hypocalcaemic response decreased with the number of zinc oxide dosings. This effect was explained as a response from the stimulation of the calcium homeostatic mechanisms. In the Zn dosed non-lactating cows responses were similar but less clear. The perspective of these findings is discussed in relation to resistance towards parturient hypocalcaemia. 相似文献
34.
Three main preventive principles against milk fever were evaluated in this literature review, and the efficacy of each principle was estimated from the results of controlled investigations. Oral calcium drenching around calving apparently has a mean efficacy of 50%–60% in terms of milk fever prevention as well as prevention of milk fever relapse after intravenous treatment with calcium solutions. However, some drenches have been shown to cause lesions in the forestomacs. When using the DCAD (dietary cation-anion difference) principle, feeding rations with a negative DCAD (measured as (Na + K) – (Cl + S)) significantly reduce the milk fever incidence. Calculating the relative risk (RR) of developing milk fever from controlled experiments results in a mean RR between 0.19 and 0.35 when rations with a negative versus positive DCAD are compared. The main drawback from the DCAD principle is a palatability problem. The principle of feeding rations low in calcium is highly efficient in milk fever prevention provided the calcium intake in the dry period is kept below 20 g per day. Calculating the relative risk (RR) of developing milk fever from controlled experiments results in a very low mean RR (between 0 and 0.20) (daily calcium intake below versus above 20 g/d). The main problem in implementing the low-Ca principle is difficulties in formulating rations sufficiently low in calcium when using commonly available feeds. The use of large doses of vitamin D metabolites and analogues for milk fever prevention is controversial. Due to toxicity problems and an almost total lack of recent studies on the subject this principle is not described in detail. A few management related issues were discussed briefly, and the following conclusions were made: It is important to supply the periparturient cow with sufficient magnesium to fulfil its needs, and to prevent the dry cows from being too fat. Available information on the influence of carbohydrate intake, and on the effect of the length of the dry period and prepartum milking, is at present insufficient to include these factors in control programmes. 相似文献
35.
R J Bailey N Krasner A L Eddleston R Williams D E Tee D Doniach L A Kennedy J R Batchelor 《BMJ (Clinical research ed.)》1976,2(6038):727-729
Determination of histocompatibility antigens in 63 patients with alcoholic liver disease showed that HLA-B8 was more prevalent in patients with cirrhosis than in controls, but among those with fatty liver and minimal fibrosis the prevalence of this antigen was normal. Another noticeable difference was the absence of HLAA28 in the cirrhotic group. In the total series of 219 patients the prevalence of antinuclear and smooth muscle antibodies was raised; they were especially prevalent in patients with cirrhosis. Raised serum IgA and IgG concentrations were also common (found in 50% and 37% respectively) and were again significantly associated with cirrhosis. In contrast, serum IgM levels, which were raised in 46% of cases, were not significantly related to the presence of cirrhosis but correlated significantly with the degree of portacaval shunting. These results support recent evidence suggesting that immune responses may be implicated in alcohol-induced liver damage, particularly in its progression to cirrhosis. 相似文献
36.
The dog is the main reservoir of Leishmania infantum, the causative agent of visceral leishmaniasis (VL) in humans in Southern Europe. In order to identify the risk of dogs from
a Leishmania non-endemic area traveling to a Leishmania -endemic area becoming infected and the risk of transmitting infection to humans in non-endemic areas an investigation was
performed, in which the results of a questionnaire were combined with the results of a serologic survey. 相似文献
37.
38.
Occurrence of cis-7-tetradecenoic acid in the envelope phospholipids of Escherichia coli K12 总被引:1,自引:0,他引:1
We have isolated a tetradecenoic acid from and have identified this new acid as -7-tetradecenoic by its 13C nuclear magnetic resonance spectrum. This identification was confirmed by conventional structural studies. The acid is a component of the phospholipids of and comprises about 15% of the total phospholipid unsaturated fatty acid. 相似文献
39.
40.
Claude Barberis Neil Moorcroft Chris Arendt Mikhail Levit Sandra Moreno-Mazza Joseph Batchelor Ingrid Mechin Tahir Majid 《Bioorganic & medicinal chemistry letters》2017,27(20):4730-4734
Novel N-substituted azaindoles have been discovered as PIM1 inhibitors. X-ray structures have played a significant role in orienting the chemistry effort in the initial phase of hit confirmation. Disclosure of an unconventional binding mode for 1 and 2, as demonstrated by X-ray crystallography, is presented and was an important factor in selecting and advancing a lead series. 相似文献