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71.
Eukaryotic cells contain nontranslating messenger RNA concentrated in P-bodies, which are sites where the mRNA can be decapped and degraded. We present evidence that mRNA molecules within yeast P-bodies can also return to translation. First, inhibiting delivery of new mRNAs to P-bodies leads to their disassembly independent of mRNA decay. Second, P-bodies decline in a translation initiation-dependent manner during stress recovery. Third, reporter mRNAs concentrate in P-bodies when translation initiation is blocked and resume translation and exit P-bodies when translation is restored. Fourth, stationary phase yeast have large P-bodies containing mRNAs that reenter translation when growth resumes. The reciprocal movement of mRNAs between polysomes and P-bodies is likely to be important in the control of mRNA translation and degradation. Moreover, the presence of related proteins in P-bodies and maternal mRNA storage granules suggests this mechanism is widely adapted for mRNA storage. 相似文献
72.
Muriel Sacks Simone K. Ringer Andrea S. Bischofberger Sabrina M. Berchtold Regula Bettschart-Wolfensberger 《Veterinary anaesthesia and analgesia》2017,44(5):1128-1138
Objective
To compare the effects of two balanced anaesthetic protocols (isoflurane–dexmedetomidine versus medetomidine) on sedation, cardiopulmonary function and recovery in horses.Study design
Prospective, blinded, randomized clinical study.Animals
Sixty healthy adult warm blood horses undergoing elective surgery.Methods
Thirty horses each were sedated with dexmedetomidine 3.5 μg kg?1 (group DEX) or medetomidine 7 μg kg?1 (group MED) intravenously. After assessing and supplementing sedation if necessary, anaesthesia was induced with ketamine/diazepam and maintained with isoflurane in oxygen/air and dexmedetomidine 1.75 μg kg?1 hour?1 or medetomidine 3.5 μg kg?1 hour?1. Ringer's lactate (7–10 mL kg?1 hour?1) and dobutamine were administered to maintain normotension. Controlled mechanical ventilation maintained end-tidal expired carbon dioxide pressures at 40–50 mmHg (5.3–6.7 kPa). Heart rate, invasive arterial blood pressure, inspired and expired gas composition and arterial blood gases were measured. Dexmedetomidine 1 μg kg?1 or medetomidine 2 μg kg?1 was administered for timed and scored recovery phase. Data were analysed using two-way repeated-measures analysis of variance and chi-square test. Significance was considered when p ≤ 0.05.Results
In group DEX, significantly more horses (n = 18) did not fulfil the sedation criteria prior to induction and received one or more supplemental doses, whereas in group MED only two horses needed one additional bolus. Median (range) total sedation doses were dexmedetomidine 4 (4–9) μg kg?1 or medetomidine 7 (7–9) μg kg?1. During general anaesthesia, cardiopulmonary parameters did not differ significantly between groups. Recovery scores in group DEX were significantly better than in group MED.Conclusions and clinical relevance
Horses administered dexmedetomidine required more than 50% of the medetomidine dose to reach equivalent sedation. During isoflurane anaesthesia, cardiopulmonary function was comparable between the two groups. Recovery scores following dexmedetomidine were better compared to medetomidine. 相似文献73.
Margot K. Sacks Romain Béraud 《The Canadian veterinary journal. La revue veterinaire canadienne》2012,53(10):1105-1108
A 7-month-old intact female German shepherd dog was presented with recurrent urinary tract infections and incontinence, ambiguous external genitalia (enlarged vulva containing a penis), and an anovestibular fistula. Anatomical structures, histopathology, and karyotyping supported a diagnosis of female pseudo-hermaphrodite, hypothesized to be a result of in utero androgenization with consequential cloacal malformation. 相似文献
74.
The 'Sydney Principles' for reducing the commercial promotion of foods and beverages to children 总被引:1,自引:0,他引:1
Swinburn B Sacks G Lobstein T Rigby N Baur LA Brownell KD Gill T Seidell J Kumanyika S;International Obesity Taskforce Working Group on Marketing to Children 《Public health nutrition》2008,11(9):881-886
A set of seven principles (the 'Sydney Principles') was developed by an International Obesity Taskforce (IOTF) Working Group to guide action on changing food and beverage marketing practices that target children. The aim of the present communication is to present the Sydney Principles and report on feedback received from a global consultation (November 2006 to April 2007) on the Principles. The Principles state that actions to reduce marketing to children should: (i) support the rights of children; (ii) afford substantial protection to children; (iii) be statutory in nature; (iv) take a wide definition of commercial promotions; (v) guarantee commercial-free childhood settings; (vi) include cross-border media; and (vii) be evaluated, monitored and enforced. The draft principles were widely disseminated and 220 responses were received from professional and scientific associations, consumer bodies, industry bodies, health professionals and others. There was virtually universal agreement on the need to have a set of principles to guide action in this contentious area of marketing to children. Apart from industry opposition to the third principle calling for a statutory approach and several comments about the implementation challenges, there was strong support for each of the Sydney Principles. Feedback on two specific issues of contention related to the age range to which restrictions should apply (most nominating age 16 or 18 years) and the types of products to be included (31% nominating all products, 24% all food and beverages, and 45% energy-dense, nutrient-poor foods and beverages). The Sydney Principles, which took a children's rights-based approach, should be used to benchmark action to reduce marketing to children. The age definition for a child and the types of products which should have marketing restrictions may better suit a risk-based approach at this stage. The Sydney Principles should guide the formation of an International Code on Food and Beverage Marketing to Children. 相似文献
75.
Ryona I Pan BS Intrigliolo DS Lakso AN Sacks GL 《Journal of agricultural and food chemistry》2008,56(22):10838-10846
The effects of light exposure on 3-isobutyl-2-methoxypyrazine (IBMP) accumulation and degradation in Vitis vinifera L. cv. Cabernet Franc berries were assessed by comparison of shaded and exposed clusters within the same vine throughout a growing season. Twenty-seven vines were shoot-thinned to create regions of high and low cluster-light exposure within each vine. Samples were collected at 10 time points starting from 5 to 130 days postbloom. The experimental design allowed for intravine comparison of IBMP levels between treatments at each time. Vine-to-vine variability of IBMP and the correlation of IBMP to malic acid were also evaluated. Cluster exposure reduced accumulation of IBMP at all preveraison time points by 21-44%, but did not increase postveraison degradation. Significant vine-to-vine variability in IBMP content was observed, with the highest level of IBMP in shaded berries in the most vigorous block of vines. Although IBMP concentration by weight decreased significantly due to dilution just prior to color change (veraison), no significant IBMP degradation per berry occurred until after color change (day 70 postbloom). By contrast, malic acid degradation began prior to color change, and malic acid concentrations were not affected by cluster exposure preveraison, but were affected postveraison. A survey of 13 sites in New York state (Seneca Lake) showed that IBMP concentrations at 2 weeks preveraison were highly correlated (R(2) = 0.936, p < 0.0001) to levels at harvest, whereas classic grape maturity indices at harvest were uncorrelated with IBMP at harvest. In summary, light exposure conditions critically influence IBMP accumulation but not IBMP degradation. 相似文献
76.
77.
78.
Muriel J. O’Brien 《American Journal of Potato Research》1972,49(2):70-72
Additional hosts for potato spindle tuber virus (PSTV) found in the suborder Solanineae are:Nolana sp. (Nolanaceae);Antirrhinum sp.,Diascia barberae, Nemesia sp., N. foetens, Penstemon sp. (Scrophulariacceae); andBrowallia speciosa (B. major) andSolanum melongena in the Solanaceae. PSTV produced no local lesions upon inoculation of these hosts. Inoculated plants ofS. melongena (eggplant, ‘Black Beauty’) were dwarfed and epinastic. These rarely used genera in the Solanineae can be readily infected with the virus; leaf and floral parts are profuse and the tissues, upon grinding, leave very little residue. 相似文献
79.
Hoar BR Chomel BB Rolfe DL Chang CC Fritz CL Sacks BN Carpenter TE 《Preventive veterinary medicine》2003,56(4):299-311
Zoonotic transmission of sylvatic plague caused by Yersinia pestis occurs in California, USA. Human infections with various Bartonella species have been reported recently. Coyotes (Canis latrans) are ubiquitous throughout California and can become infected with both bacterial agents, making the species useful for surveillance purposes. This study examined the geographic distribution of 863 coyotes tested for Y. pestis and Bartonella vinsonii subsp. berkhoffii serologic status to gain insight into the natural history of B. vinsonii subsp. berkhoffii and to characterize the spatial distribution of the two agents.
We found 11.7% of specimens positive to Y. pestis and 35.5% positive to B. vinsonii subsp. berkhoffii. The two pathogens had distinct spatial clusters: Y. pestis was more prevalent in eastern portions of the state and B. vinsonii subsp. berkhoffii in coastal regions. Prevalence of Y. pestis increased with increasing elevation, whereas prevalence of B. vinsonii subsp. berkhoffii decreased with increasing elevation. There were differences in the proportions of positive animals on a yearly basis to both pathogens. 相似文献
80.