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241.
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In a recent letter (1) to the New Zealand Veterinary Journal on perinatal mortality in piglets, the reported sow Vitamin E supplementation of 50 IU/sow/day was slightly lower than that typically used on most commercial farms in New Zealand. Normal sow dietary supplementation is in the range of 30-60 IU per kg dry matter (DM).  相似文献   
243.
We investigated the requirements for a commercial vitamin premix in diets of Lytechinus variegatus. Small L. variegatus (ca. 28 mm diameter) were collected from Saint Joseph Bay, Florida, and acclimated to laboratory conditions (32 ppt salinity, 22 C, 12:12 photoperiod) for 3 wk, then placed individually into plastic mesh cages (n = 16 per treatment). Sixteen urchins were dissected to obtain initial weights of organs (gut, gonad, test). Each treatment was fed one of five semipurified diets supplemented with levels of a commercial shrimp vitamin premix ranging from 0 to 0.9% dry weight. At 4‐wk intervals, wet weights and test diameters were measured. At 16 wk, urchins were dissected and organs weighed. Significant weight gain and 100% survival was observed with all diets. At 16 wk, urchins fed 0% vitamin premix exhibited no noticeable pathology but had significantly less weight gain than those fed the 0.6% vitamin premix. Those fed the 0.6% vitamin premix had significantly greater weight gain than all other diets (P < 0.0001). Gonad weights increased in all treatments, but did not vary significantly. Under the conditions of this study, L. variegatusexhibited a satisfactory nutritional response. Experiments are planned to determine specific dietary vitamin requirements for L. variegatus.  相似文献   
244.
Research is often an essential component of completing a veterinary medicine degree, with universities worldwide aiming to teach students a variety of techniques and general research comprehension and skills. As universities worldwide navigated the COVID-19 pandemic, it was often necessary to move towards distance learning, this was employed for the research module at The University of Nottingham, School of Veterinary Medicine and Science. Following completion of their independent research project, each student cohort was sent a student evaluation of the module questionnaire and quantitative and qualitative analysis was undertaken. In addition, assessment outcomes based on dissertation grade, supervisor grade and overall module score were analysed quantitatively. This was conducted on both the individual cohorts and between the pre- and peri-pandemic groups, ranging from 2017–2018 through to 2021–2022 cohorts. The students received increased dissertation and supervisor grades (by nearly 6%) during the 2021–2022 peri-pandemic cohort, when compared to the pre-pandemic cohorts, but did differ significantly compared to the 2020–2021 cohort. The pre- and peri-pandemic Likert-scale ratings for module organisation and assessment criteria were similar, workload management and the ability to explore concepts and ideas was reduced in the peri-pandemic cohorts, whereas the accessibility to resources was increased in the peri-pandemic students compared to those taught prior to the pandemic. Student feedback can provide essential information when designing and managing research projects and when compared to assessment grades it can help us understand attainment, essential information when providing a quality university level education whilst supporting student welfare following the COVID-19 pandemic.  相似文献   
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Results of two field experiments, one on SA 1 pigeonpea in rainfed and the other on Co.5 pigeonpea in irrigated conditions revealed thatBacillus thuringiensis var.kurstaki (B.t.k.) (Delfin), its combinations with nuclear polyhedrosis virus ofHeliothis armigera andChrysoperla carnea were as effective as endosulfan in reducing the pod borers,Heliothis armigera andExelastis atomosa. However,B.t.k. 1.25 kg+endosulfan 175 g/ha orB.t.k. 2.5 kg+HaNPV, 250 LE/ha gave better control of damage to flowers and pods thanB.t.k. applied alone on SA 1 pigeonpea. The yield differences between these treatments were not significant. A combination of HaNPV 250 LE/ha+endosulfan 175 g/ha was superior toB.t.k. Similar trend was seen on Co.5 pigeonpea. Release ofC. carnea second instar larvae 1 lakh/ha was not effective in increasing the yield of pigeonpea.  相似文献   
248.
An investigation was made of bark necrosis on the stems of London plane in a tree nursery. It appears likely that the damage was caused by fungi such as Gnomonia platani and Cylindrocarpon beteronema invading trees predisposed to disease by heavy summer pruning.  相似文献   
249.
Research conducted on shoot dieback of lodgepole pine, Pinus contorta, during the early 1980's in west Scotland is summarised. The dieback symptoms and their stages of development are described. Ramichloridium pini de Hoog and Rahman was regularly isolated from bark and xylem tissue of dieased shoots. Artificial inoculations established that this fungus was the cause of the disease.  相似文献   
250.
Ten fruit and kernel traits were measured in 152 Irvingia gabonensis and 293 Dacryodes edulis trees from 6 villages in Cameroon and Nigeria. Frequency distribution curves were used to examine the range of variation of each trait of each species in each village and aggregated into national and regional populations. There were differences between the village sub-populations, with regard to the normality (e.g., mean kernel mass of D. edulis) or skewness (e.g., mean flesh depth of D. edulis) of the distribution curves and in the degree of separation between the individual village populations along the x axis, resulting in the development of a bimodal distribution in the regional population. For all traits, populations of both species differed significantly between countries, but only in D. edulis were there significant differences between the Cameroon populations. On the basis of the results of this study, D. edulis can be said to be virtually wild in Nigeria but semi-domesticated in Cameroon, while I. gabonensis is wild in Cameroon and semi-domesticated in Nigeria. These results are discussed with regard to a hypothesis that the range and frequency of variation in the different populations can be used to identify five stages of domestication. From a comparison of the frequency distribution curves of desirable versus undesirable traits, and statistically identifyable changes in skewness and kurtosis, it is concluded that as a result of the farmers’ own efforts by truncated selection, D. edulis is between Stages 2 and 3 of domestication (with a 67% relative gain in flesh depth) in Cameroon, while I. gabonensis in Nigeria is at Stage 2 (with a 44% relative gain in flesh depth). In this study, genetic diversity seems to have been increased, and not reduced, by domestication. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
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