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511.
Emanuele Cristiny Goes Gabriela Cardoso Dal Pont Priscila Raijche Oliveira Chayane da Rocha Alex Maiorka 《Journal of animal physiology and animal nutrition》2021,105(2):294-304
The aim of this study was to evaluate the effects of increasing doses of putrescine injected in ovo on hatchability, intestinal morphology and pre-starter performance of broilers. For this purpose, 720 eggs from broiler breeders were separated into a negative control (no injection) and injection treatments with increasing doses of putrescine (0.05; 0.1; 0.15 and 0.2%), totalling five treatments of 144 eggs each. Eggs were distributed in a completely randomized design inside the setter and the injection of solutions occurred at 17 days of incubation. After hatch, 330 birds were housed in mixed lots following the original treatments, totalling 5 treatments of 6 replicates with 11 birds each. Six birds per treatment were weighed and euthanized by cervical dislocation to collect the liver, intestine and breast 24 hr after injection, at hatch and 24 hr after hatch. At 2 days of age, intestines were collected from 4 animals per treatment to analyse histomorphology. The effects of putrescine levels were evaluated by polynomial regression models, ANOVA and Tukey test at 5% probability. The hatchability decreased linearly in response to increased doses of putrescine. The percentage of residual yolk was lower in animals that received putrescine compared to the control. After injection, the percentage of breast increased linearly, and the percentage of intestine had a quadratic response to increased doses of putrescine. However, 24 hr after hatch, the percentage of intestine linearly decreased, and the percentage of liver linearly increased in response to increased doses of putrescine. Villus height increased quadratically, crypt depth decreased linearly, and goblet cells increased linearly in response to the putrescine dose. FI and BWG were not affected in the pre-starter phase; however, FCR increased in response to increased levels of putrescine. Due to putrescine effects on embryos, it is recommended that the doses injected in ovo not exceed 0.1%. 相似文献
512.
Shaziya Hussain Rani Alex Rafeeque R. Alyethodi Shalini Sharma Nitika Verma Ajayvir Singh Sirohi Umesh Singh Sushil Kumar Naimi Chand Gyanendra S. Sengar Ankur Sharma Rachna Tyagi Sarmesh Arya Srikant Tyagi 《Reproduction in domestic animals》2021,56(5):736-743
In cattle production systems, an intense selection pressure for production traits has resulted in the decline of fertility traits. To optimize an efficient reproduction system, the inclusion of both male and female fertility traits in the selection process is very much essential. RAPD (Random Amplified Polymorphic DNA) was developed as a molecular biology tool and has been extensively used, to study intra- and interspecific genetic diversity. The present study was undertaken to utilize RAPD primers to investigate the association between DNA markers and semen quality traits viz. Sperm concentration, total sperm count ejaculate and initial sperm motility and thereby to identify good/poor semen producers. DNA isolated from the blood samples of healthy bulls was subjected to RAPD-PCR. The multiple regression analysis followed by independent t test was carried out to identify suitable markers. Based on the results, only 12 bands were identified as marker suitable for any of the quality trait. This includes, OPA2 ~ 760, OPA2 ~ 700, OPA6 ~ 1,200, OPA9 ~ 400, OPA9 ~ 380, OPA12 ~ 970, OPA14 ~ 715, OPA14 ~ 605, OPA16 ~ 485, OPA17 ~ 860 and OPA18 ~ 480. Multiple regression analysis selected, OPA2 ~ 760 and OPA2 ~ 1,750 for sperm concentration and OPA2 ~ 760, OPA2 ~ 700, OPA9 ~ 620, OPA4 ~ 670 and OPA18 ~ 1,015 for total sperm count/ejaculate. But the t test revealed a significant association between OPA2 ~ 760 and total sperm count. Further, discriminant function analysis also identified this marker in the first step itself. The results of the present study can be exploited as a low-cost alternative strategy for identification of good /poor semen producers in crossbred bulls at an early age. 相似文献
513.
Gu Z Kaul M Yan B Kridel SJ Cui J Strongin A Smith JW Liddington RC Lipton SA 《Science (New York, N.Y.)》2002,297(5584):1186-1190
Matrix metalloproteinases (MMPs) are implicated in the pathogenesis of neurodegenerative diseases and stroke. However, the mechanism of MMP activation remains unclear. We report that MMP activation involves S-nitrosylation. During cerebral ischemia in vivo, MMP-9 colocalized with neuronal nitric oxide synthase. S-Nitrosylation activated MMP-9 in vitro and induced neuronal apoptosis. Mass spectrometry identified the active derivative of MMP-9, both in vitro and in vivo, as a stable sulfinic or sulfonic acid, whose formation was triggered by S-nitrosylation. These findings suggest a potential extracellular proteolysis pathway to neuronal cell death in which S-nitrosylation activates MMPs, and further oxidation results in a stable posttranslational modification with pathological activity. 相似文献
514.
de Lozanne A 《Science (New York, N.Y.)》2004,305(5682):348-349
515.
In the absence of suitable technology to measure and map the dry matter (DM) yield distributions of forage grass crops within individual fields, a manual procedure of yield mapping has been developed. Samples of herbage are collected just prior to each silage harvest from known grid points within a field, and sward DM yields at each point are predicted from the mineral composition of the herbage, using empirical mathematical models. Yield maps (and maps of sward nutrient status) are then produced by kriging interpolation between the point data. To make the most efficient use of time and resources, however, sampling intensity needs to be kept to the absolute minimum necessary for interpolation purposes. The aim of the present study was to examine the spatial variability in sward DM yield and mineral nutrient status in a large grass silage field under a three-cut system, and devise optimal sampling strategies for mapping the distributions of these parameters at each cut. Herbage samples were collected from the field, prior to each harvest, at 25 m intervals in a regular rectangular grid to provide databases of herbage nutrient contents and DM yields. Different data combinations were abstracted from these databases for comparison purposes, and ordinary kriging used to produce interpolated maps of DM yield and sward N, P, K and S statuses. The results suggested that a sampling density of just seven samples per hectare was adequate for estimating the true population means of sward DM yield and sward N, P, K, and S statuses. For mapping purposes, it was found that the best compromise between interpolation accuracy and sampling efficiency was to collect herbage samples in a 35.4 m×35.4 m equilateral triangular sampling pattern. 相似文献
516.
Barker A 《Science (New York, N.Y.)》2005,309(5742):1814
517.
The use of Precision Agriculture techniques to investigate agronomically significant soil factors and their relationship to wheat quality on a site-specific basis, was conducted during the winter 1996 wheat season in response to the growing concerns associated with wheat quality in Australia. A field of durum wheat was selected in Northern New South Wales, in which wheat and soil samples were taken from sites located within the field with the help of a Global Positioning System (GPS).Geostatistical methods were used to interpolate the data and produce maps of the field representing the spatial variability of all the soil and wheat properties. With the aid of these maps and empirical modeling techniques, relationships between the wheat and soil factors were determined.Areas within the field with lower soil profile available water capacities, caused by a combination of coarser soil texture and lower organic carbon content, probably contributed to water stress during grain-fill, which interacted with soil nitrogen to give higher protein levels. These areas of the field had lower yields and smaller 1000-kernel weights. Protein quality was found not to be compromised by increasing protein concentrations which resulted from water stress.The benefits of using precision agriculture techniques as a method for segregating wheat by protein at harvest to increase profits are described. 相似文献
518.
Space missions currently on the drawing boards are expected to gather data at rates exceeding the transmission capabilities of today's telemetry systems by many orders of magnitude. Even on current missions, onboard data compression techniques are being implemented to compensate for lack of transmission speed. But while data compression can minimize the loss of data, it is no substitute for transmitting all of the data through a faster communications link. The transmission problem will soon reach crisis proportions and will affect astronomical, Earth resources, geophysical, meteorological, planetary and other space science missions. To overcome this communications bottleneck, the authors advocate the implementation of telemetry systems based on near-infrared laser transmission techniques. The fiber-optics communications industry has developed most of the basic components required for signal transmission in this wavelength band, which should make such a system affordable on scales relevant to the cost of anticipated space science missions. 相似文献
519.
Conestoga is an early, white-skinned potato with very vigorous early growth. It has very good boiling, baking and chipping qualities. Yield is comparable to that of Superior, with chip colour and specific gravity slightly higher than Norchip’s. Conestoga is moderately resistant to virus leafroll, net necrosis, early blight, and common scab and moderately susceptible to mild and rugose mosaic. 相似文献
520.
Talebi Seyed Mehdi Tabaripour Raheleh Matsyura Alex 《Genetic Resources and Crop Evolution》2022,69(1):285-296
Genetic Resources and Crop Evolution - In the present study, we utilized ISSR molecular markers to investigate infraspecific and infrageneric genetic variations in 34 populations from 25 Nepeta L.... 相似文献