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991.
Armillaria species from Japan were characterized using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) of the intergenic spacer region-1 (IGS-1) of ribosomal DNA (rDNA). Eleven different digestion patterns by restriction endonuclease Alu I were found among 70 isolates of seven Armillaria species in Japan. Isolates within Armillaria nabsnona, A. ostoyae, A. cepistipes, and Japanese biological species E showed the same Alu I digestion patterns. Five Alu I patterns were detected for A. gallica, three patterns for A. mellea, and two patterns for A. tabescens. Seven Armillaria species in Japan were clearly distinguished by using the profiles obtained when PCR products were digested with Alu I, Msp I, and Hae III restriction enzymes. There was considerable variability of Alu I restriction sites within the IGS-1 between the isolates of five Armillaria species, A. gallica, A. nabsnona, A. cepistipes, A. mellea, and A. tabescens, in Japan and those of their European and North American counterparts. 相似文献
992.
Kenji Fukuda Yuko Nishiya Masayuki Nakamura Kazuo Suzuki 《Journal of Forest Research》1997,2(2):79-84
Recently, symptoms of decline have been widely observed in Yezo spruce (Picea jezoensis) and Todo fir (Abies sachalinensis) in Hokkaido. In order to clarify the mechanism of decline, the water status of Yezo spruce and Todo fir trees in the Tokyo
University Forest in Hokkaido were investigated. The decline is observed mainly in stands damaged by Typhoon XV of 1981 (D-stands),
but is not observed in undamaged stands (C-stands). Sampled trees in both types of stands were selected, the severity of their
decline estimated, diurnal water potentials measured and water relation parameters such as water potential at turgor-loss
point (
) and osmotic potential at full saturation (
) were estimated by pressure-volume analysis. The diurnal trends of leaf water potential and midday water potential (
) of the sample trees were clearly different between the D-stands and the C-stand. Water stress in trees was much more severe
in the D-stands than in the C-stand.
and
of the declining trees were lower in the D-stands than in the C-stand. However,
and
were not significantly different between declining trees and healthy-looking trees in D-stands. It was concluded that stand-level
water stress, induced by the destruction of the canopy by the typhoon, was associated with the decline symptoms. The measurement
of water relation parameters proved to be useful for diagnosis and prediction of decline at a stand level in this area. 相似文献
993.
In the development of pine wilting disease caused by Bursaphelenchus lignicolus, water status in pines plays an important role in the pinenematode relationship. Levelling off in transpiration causes a population growth of nematodes in the wood. Such pines invariably wilt several weeks after the reduction of transpiration. The paper contains details of oleoresin exudation, transpiration and xylem water potential as well as the nematode population in the wood in connection with disease development. 相似文献
994.
Satoshi Suzuki Naotaka Ogino Ikki Mitsui Hiroyuki Ito Takuro Kariya 《Journal of veterinary diagnostic investigation》2021,33(1):87
CD71 is an immunohistochemical marker used in diagnosing acute myeloid leukemia (AML) M6-Er in humans; however, to our knowledge, it has not been reportedly used for immunohistochemistry in veterinary medicine. We evaluated the pathologic features of AML M6-Er in a retrovirus-negative cat and used CD71 to support the diagnosis. A 4-y-old spayed female Scottish Fold cat was presented with lethargy, anorexia, and fever. Whole-blood PCR assay results for pro feline leukemia virus/pro feline immunodeficiency virus and feline vector-borne diseases were negative. Early erythroid precursors were observed in the peripheral blood smear. Fine-needle aspiration of the enlarged spleen and splenic lymph node showed many early erythroid precursors. Bone marrow aspirate smears revealed erythroid hyperplasia with 68.4% erythroid lineage and 3.6% rubriblasts. Dysplastic cells infiltrated other organs. The patient was diagnosed with myelodysplastic syndrome, progressing to the early phase of AML M6-Er. The patient died on day 121 despite multidrug treatments. Postmortem examination revealed neoplastic erythroblasts infiltrating the bone marrow and other organs. Neoplastic cells were immunopositive for CD71 but immunonegative for CD3, CD20, granzyme B, von Willebrand factor, CD61, myeloperoxidase, and Iba-1. Although further studies are necessary for the application of CD71, our results supported the morphologic diagnosis of AML M6-Er. 相似文献
995.
Risa Shintani Seongjin Oh Yutaka Suzuki Satoshi Koike Yasuo Kobayashi 《Animal Science Journal》2021,92(1):e13620
The effect of ginkgo fruit addition on methane production potential of cattle feces and slurry was assessed in relation to other fermentation products and the microbial community. Holstein cattle fresh feces and slurry were left at 30°C for 0, 30, 60, 90, and 180 days with/without ginkgo fruit to monitor the effect on fermentation potential. With the addition of ginkgo fruit, methane production potential of feces was reduced on Day 30 and thereafter, and that of slurry was consistently reduced over the experimental period. As a general trend, ginkgo fruit addition resulted in decreased acetate and increased propionate in feces and acetate accumulation in slurry. With ginkgo fruit addition, MiSeq analyses indicated decreases in methanogen (in particular Methanocorpusculum), Ruminococcaceae, and Clostridiaceae populations and increases in Bacteroidaceae and Porphyromonadaceae populations, which essentially agreed with quantitative real-time polymerase chain reaction (qPCR) assay results. These data indicate that direct addition of ginkgo fruit to cattle excreta is useful for reducing methane emissions by altering the microbial community structure. The application of ginkgo fruit to lower methane emissions from cattle excreta is, therefore, useful in cases in which the excreta is left without special management for a long period of time. 相似文献
996.
Rafael Massami Suzuki Matheus de Paula Reis Juliana Célia Denadai Letícia Graziele Pacheco Carolina Cardoso Nagib Nascimento Nilva Kazue Sakomura 《Journal of animal physiology and animal nutrition》2021,105(5):960-964
Most amino acid requirement trials appear for whole-body responses, but there is little information concerning amino acid incorporation in individual tissues, which may vary according to the age. L-[15N] threonine was used to evaluate its incorporation rate and distribution among broiler tissues in different ages. Seventy-two male broiler chickens were distributed into three different phases: starter (4 to 9 days old), grower (18 to 23 days old) and finisher phase (32 to 37 days old). L-[15N] threonine was added on balanced diets, and birds were fed for five days in each phase. Enriched samples of breast muscle, feathers, liver, jejunum and plasma were collected at 0, 6, 12, 24, 48, 72, 96 and 120 hr after fed birds with the tracer in each phase. In the tissues were analysed dry matter, nitrogen and stable nitrogen. The 15N isotope abundance according to the time was fitted into exponential or linear equations using a same intercept. The ratio of the steepness or slope coefficients was determined to compare the L-[15N] threonine incorporation according to the age. In addition, L-[15N] threonine mass balances were performed to assess the L-[15N] threonine distribution among the evaluated tissues. Except for feathers, the L-[15N] threonine incorporation rate decreased with ageing. Taking into account the L-[15N] threonine distribution in the tissues, only in the jejunum was not observed an increase as the broiler grew. The L-[15N] incorporation varied in each tissue and according to the age of the broiler chickens. These outcomes could be useful to comprehend changes in amino acid requirements tissue-specific according to age. 相似文献
997.
Kazuki Komatsu Tsugumi Iwasaki Kosuke Murata Hideaki Yamashiro Valerie Swee Ting Goh Ryo Nakayama Yohei Fujishima Takumi Ono Yasushi Kino Yoshinaka Simizu Atsushi Takahashi Hisashi Shinoda Kentaro Ariyoshi Kosuke Kasai Masatoshi Suzuki Maria Grazia Palmerini Manuel Belli Guido Macchiarelli Toshitaka Oka Manabu Fukumoto Mitsuaki A. Yoshida Akifumi Nakata Tomisato Miura 《Reproduction in domestic animals》2021,56(3):484-497
Since the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, we have established an archive system of livestock and wild animals from the surrounding ex-evacuation zone. Wildlife within the alert zone have been exposed to low-dose-rate (LDR) radiation for a long continuous time. In this study, we analysed the morphological characteristics of the testes and in vitro fertilization (IVF) capacity of cryopreserved sperm of racoons from the ex-evacuation zone of the FDNPP accident. The radioactivity of caesium-137 (137Cs) was measured by gamma-ray spectrometry, and the measured radioactivity concentration was 300–6,630 Bq/kg in the Fukushima raccoons. Notably, normal spermatogenesis was observed in the seminiferous tubules of the testes, with the germinal epithelium composed of a spermatogenic cell lineage with no evident ultrastructural alterations; freeze-thawing sperm penetration ability was confirmed using the interspecific zona pellucida-free mouse oocytes IVF assays. This study revealed that the chronic and LDR radiation exposure associated with the FDNPP accident had no adverse effect on the reproductive characteristics and functions of male raccoons. 相似文献
998.
盐分再分配条件下河套灌区冲洗水量的数值模拟 总被引:7,自引:6,他引:7
该文旨在探讨干旱缺水地区长期灌溉条件下,合理解决节水灌溉与冲洗灌溉间矛盾的途径,为在该地区实施节水灌溉战略提供理论依据。采用修正的对流扩散模型(SOTR)及特征有限元方法对中国内蒙古河套灌区冲洗—蒸发条件下的冲洗定额进行数值模拟研究。并用γ射线测定土柱土壤水盐运移结果标定了数值模拟结果。重点分析了基于土壤水动力学与溶质动力学原理,再灌溉冲洗与再分配条件下,均质垂直剖面上溶质运移过程;长期灌溉条件下,干旱地区土壤盐分布与冲洗定额、初始土壤盐分含量、地下水位埋深及地下水矿化度间的内在联系;在此基础上,确定节水灌溉条件下河套灌区最优的冲洗定额。该成果对于促进该地区农业可持续发展具有一定的指导意义 相似文献
999.
The separation and identification of pigments, chlorophylls, and carotenoids of seven teas and fresh leaf of tea (Camellia sinensis) by high-performance liquid chromatography (HPLC) are described. HPLC was carried out using a Symmetry C(8) column with a photodiode array detector. Pigments were eluted with a binary gradient of aqueous pyridine solution at a flow rate of 1.0 mL/min at 25 degrees C. HPLC analyses achieved the separation of more than 100 pigment peaks, and 79 pigment species, 41 chlorophylls, and 38 carotenoids were detected. The presence of degraded chlorophylls was a common feature, and the number and the variety of pigments differed with tea species. Generally, the numbers of chlorophyll species tended to increase with processing steps, while carotenoid species were decreased, especially by heating. Particularly in green teas, a change of carotenoid structure, conversion of violaxanthin to auroxanthin, occurred. In hot water extracts of teas, both chlorophylls and carotenoids were also detected, but the concentration of chlorophylls was less than 2% as compared with acetone extracts. The pigment compositions were compared between tea species, and they are discussed in terms of the differences in their manufacturing processes. 相似文献
1000.