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991.
饵料和养殖密度对中国对虾幼虾生长及存活率的影响 总被引:6,自引:0,他引:6
在实验用虾遗传背景一致的情况下,分析了3种饵料(配合饲料、冰冻鲜鱼肉和活卤虫)和4个不同的养殖密度对小水体中国对虾幼虾生长和存活率的影响。结果表明,饵料和饲养密度对中国对虾幼虾生长及存活率有显著影响。在饵料、养殖密度单因子实验及饵料和养殖密度相结合的双因子实验中,幼虾的生长均表现出极其显著的差异(P<0.01),活卤虫对幼虾生长的效应尤为突出。而养殖密度对中国对虾的行为生物学、个体间体重增量均有影响。随着养殖密度的提高,中国对虾增重变慢;同时,个体间体重增量差异变大。随着养殖密度的增加,中国对虾幼虾的存活率呈下降趋势,但不同饵料对存活率影响变化幅度较大,波动在58.1%~85.2%之间,其中投喂活卤虫养殖密度为50尾/桶的存活率最高(85.2%);投喂配合饵料4个养殖密度梯度的存活率变化不明显;而投喂冰冻鱼肉4个养殖密度梯度的存活率变化较大。因此,采用合适的饵料和养殖密度,能够提高中国对虾的生长速度,提高对虾养成存活率,改善生长过程中对虾群体体长、体重的整齐度。 相似文献
992.
蟹类是福建海区重要的经济渔获种类之一。本文基于2009年1月-011年12月期间进行的蟹类调查资料,分析了福建中南部近海四种捕捞作业渔获物中蟹类的种类组成和分布特点。结果表明:福建中南部近海海域有蟹类94种,隶属16科、53属,以亚热带和热带的暖水性种为主,与南海关系最为密切,而与黄、渤海关系较为疏远。从蟹种分布区域看,这些蟹类在浅海均有分布,其中26.6%的蟹类既分布于浅海又分布于潮间带。从蟹种个体大小看,福建海区蟹类多数属于中小型种类。高强度捕捞加剧了对蟹类资源的破坏,因此需要调整捕捞作业结构,拓展外海蟹类捕捞作业,开展资源动态监测和苗种放流增殖工作,并实施TAC管理制度。 相似文献
993.
对秦皇岛市发展海洋休闲渔业的优势、劣势、机会与挑战进行分析。秦皇岛应该充分利用现有的资源优势、区位优势和市场优势,借势有利的规划和政策导向,通过深度开发海洋休闲渔业旅游产品,不断完善接待和服务设施,提高从业人员的综合素质来不断提高秦皇岛市海洋休闲渔业的竞争力。 相似文献
994.
Panagiotis E Simitzis Aristeidis Tsopelakos Maria A Charismiadou Alkisti Batzina Stelios G Deligeorgis Helen Miliou 《Aquaculture Research》2014,45(11):1759-1770
The effects of different stunning/killing procedures on flesh quality of European sea bass were investigated: (1) anaesthesia with clove oil, (2) anaesthesia with 2‐phenoxyethanol, (3) percussive stunning, (4) immersion in ice/water slurry, (5) chilling on ice and (6) anaesthesia with clove oil followed by immersion in ice/water slurry. Muscle pH values were significantly lower in sea bass anaesthetized or stunned by a blow to the head compared with fish immersed in ice/water slurry, chilled on ice or immersed in ice/water slurry after clove oil anaesthesia. Lightness was highest in sea bass anaesthetized by 2‐phenoxyethanol or percussively stunned and lowest in ice‐chilled fish. Redness and yellowness were highest in fish chilled on ice and lowest in fish anaesthetized with clove oil. Liquid loss, fat loss and shear values were not significantly different among the procedures. In general, lipid oxidation values during refrigerated or frozen storage did not significantly differ among treatment groups. Combination of clove oil anaesthesia followed by chilling on ice/water slurry appears to improve both flesh quality and welfare of sea bass, although the implementation of further studies is warranted to consolidate this finding. 相似文献
995.
针对目前山东省内多数苹果园存在的规模化、机械化管理水平不高,传统灌溉施肥模式废水废肥等问题,提出结合实际情况在不同规模的苹果园内应用不同模式的水肥一体化系统,介绍了不同水肥一体化模式的适用范围,总结了苹果园应用水肥一体化技术具有节约水肥药、改善苹果品质、保护土壤等优点,对促进山东省苹果生产方式转型升级、实现苹果产业绿色高效高质发展具有积极作用。 相似文献
996.
美系獭兔的胴体性状和肉品质特性研究 总被引:4,自引:0,他引:4
通过对20只美系獭兔屠宰性能和肉品质的测定,研究獭兔的生产性能和肉质特性及它们之间的关系,结果表明:美系獭兔5月龄的平均体重为2.533 kg,商用皮重0.410 kg,屠宰率为60.70%,右后腿重0.182 kg,体长和腰周长分别为30.69和18.04 cm;美系獭兔背最长肌和后腿肉的pH1(宰后1 h的pH)分别为6.42和6.43,pH24(宰后24 h的pH)分别为6.22和6.35,肉色L*值分别为54.66和52.67,a*值分别为12.37和9.89,b*值分别为9.06和4.08;兔肉的滴水损失、熟肉率、蒸煮损失、剪切力值、水分含量和肌内脂肪含量分别为2.06%、62.12%、30.44%、2.453 kg.f、73.60%和1.67%。商用皮重与热胴体重、体长存在极显著的正相关(P<0.01),与商用胴体重存在显著的正相关(P<0.05)。兔的体重(热胴体、商用胴〖JP2〗体、右后腿)、体型(体长和腰周长)与滴水损失、蒸煮损失呈负相关,与熟肉率、剪切力值呈正相关,但相关性都不显著(P>0.05)。 相似文献
997.
Itaru Yamaguchi Kensuke Myojo Hiroko Sanada Eri Sudo Sayaka Ootsuka Hiroshi Okumura Atsuko Takami Tomomi Yoneshige Yui Suzuki Minami Imaizumi Chie Takada Naoya Kimoto Koji Saeki Katsumi Takaba 《Journal of toxicologic pathology》2013,26(3):301-307
We histopathologically and immunohistochemically investigated a case of malignant
lymphoma that spontaneously developed in a male common marmoset at two years of age.
Beginning at two years four months of age, the animal had an enlargement of the
submandibular and inguinal lymph nodes, small subcutaneous nodules near the right breast
and an approximately fivefold increase in peripheral lymphocyte count compared with the
previous examination value. The postmortem findings at two years eight months of age
showed lymphadenopathy with enlargement of the thymus and spleen. Small- to
intermediate-sized neoplastic lymphocytes had diffusely proliferated in the enlarged
nodes. The neoplastic cells were pleomorphic and had irregularly shaped nuclei. The
nuclear chromatin staining revealed hyperchromatism in the small-sized cells, and the
intermediate-sized cells exhibited vesicular staining. An immunohistochemical examination
indicated that the neoplastic lymphocytes were positive for CD3 and negative for CD20,
thus suggesting that they had originated from T cells. In addition, the proliferation of
high endothelial venules and reactive epithelioid histiocytes was observed. Scattered
tingible body-laden macrophages were infrequently detected. Neoplastic lymphocytes were
also observed in the thymus, spleen, heart, lungs, liver, kidneys, adrenal glands and
femoral and sternal bone marrow. This malignant lymphoma in a young male common marmoset
was considered to fit the category of “peripheral T-cell lymphoma, not otherwise specified
(PTCL-NOS)” according to the new WHO system of classification. 相似文献
998.
999.
简要介绍了新研制的贝类壳长电视测量仪的工作原理,及利用这一新的测试手段,根据不同实验条件比较实验的结果所建立的一套用来评价有毒物质对贻贝生长影响的测定方法。该方法快速灵敏、简便可行,在今后的生物测试和生物监测中具有广泛的应用价值。 相似文献
1000.
M. Bassompierre T.H. Ostenfeld E. McLean K. Rungruangsak Torrissen 《Aquaculture International》1998,6(1):47-56
Growth and in vitro digestion was examined in three iso-trypsin phenotypes (patterns 1, 2 and 2) of Atlantic salmon, Salmo salar. Fish grew equally well during the 128 day experiment irrespective of phenotype. At day 64 and 91, weight-specific growth rate of 2 phenotype animals were significantly lower (p < 0.05). At the end of the experiment, significant differences (p < 0.05) were noted between groups with respect to size. An in vitro method was used to examine protein digestion by the different trypsin phenotypes. Three fish meals (FM I > FM II > FM III) of high, medium and low quality, as defined by chemical analyses, were used. Phenotype 1 was able to differentiate between three fish meals ranking FM I > FM II > FM III. In contrast, phenotypes 2 and 2 were not able to separate between meals. In vitro digestion efficiency was dependent upon the three salmon types, ranking phenotype 2 > 1 = 2. 相似文献