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71.
72.
鸡白细胞介素-6原核表达及双抗夹心ELISA方法的建立 总被引:1,自引:0,他引:1
应用分子生物学技术原核表达ChIL-6,以ChIL-6重组蛋白为免疫原,按免疫程序分别制备兔抗和鼠抗IL-6重组蛋白的多克隆抗体。应用此抗体建立双抗夹心EL-ISA方法后,为了优化此方法本试验对该方法的最佳试验条件、标准曲线、重复性和初步应用进行确定。结果显示,经SDS-PAGE和Western-blot分析,表明ChIL-6在大肠杆菌中正确表达,为了建立检测ChIL6的双抗夹心ELISA方法,本试验应用表达的重组蛋白制备兔抗和鼠抗多克隆抗体。建立的双抗夹心ELISA方法最佳反应条件为包被抗体的质量浓度为50mg/L,4℃过夜;酶标二抗稀释度为1:400,37。C1h;应用该方法检测感染金黄色葡萄球菌后的ChIL-6,其结果与本实验室之前应用人的ELISA试剂盒检测的结果相似。结果表明,本试验建立的检测ChlL-6的双抗夹心ELISA方法可用于临床。 相似文献
73.
AIM: To investigate the effects of different lighting on the reproductive system in depressive female rats. METHODS: Healthy adult female rats were randomly chosen as control group, and the depressive adult female rats in SPF grade were randomly divided into 5 groups(7 rats each):depressive model group, sulfur lamp group, heat radiation lamp group, fluorescent lamp group and LED lamp group. After 45 d of continuous illumination, the estrous cycle was observed by the vaginal exfoliated cells, and the organ indexes of ovary and uterus were calculated. The concentrations of estiadrol(E2), prolactin(PRL), progesterone(PROG) and testosterone(T) in the serum were detected by ELISA, and the histopathological lesion of ovary was observed under microscope with HE staining. RESULTS: The estrous cycle exhibited serious disorder, the ovaries exhibited serious congestion, and the organ indexes of ovary and uterus and the concentrations of E2, PRL, PROG and T decreased significantly in the rats in depressive model group compared with control group(P<0.05). The estrous cycle and histopathological damage of ovary were obviously improved, and the concentrations of E2, PRL, PROG and T were significantly increased after the sulfur lamp lighting in the depressive female rats compared with depressive model group. No obvious change and improvement of the reproductive functions in the heat radiation lamp group, fluorescent lamp group and LED lamp group was observed. CONCLUSION: The reproductive functions of depressive female rats are improved by sulfur lamp lighting. 相似文献
74.
目的探讨维持性血透(MHD)患者Palindrome导管晚期功能不良的相关因素。方法收集53例使用Palindrome导管的MHD患者临床资料,用Cox风险回归分析导管晚期功能不良的相关因素。结果单因素Cox回归分析显示原发病、置管部位、临时导管留置时间、低血压发生次数、红细胞压积、超滤率与导管晚期功能不良相关(P<0.01或0.05)。多因素Cox回归分析显示置管部位、红细胞压积、超滤率是导管晚期功能不良的独立影响因素(P<0.01或0.05),相对危险度分别为2.310、1.254、1.623。结论置管部位、红细胞压积、超滤率是MHD患者Palindrome导管晚期功能不良的独立影响因素。 相似文献
75.
Production of syringomycins and syringopeptins by Pseudomonas syringae pv. atrofaciens 总被引:1,自引:0,他引:1
All virulent strains of Pseudomonas syringae pv. atrofaciens produce in vitro substances with syringomycin-like features. All strains inhibited the growth of Geotrichum candidum in the plate assay although the extent of their growth inhibition was variable.
Purification of bioactive culture extracts of a highly virulent strain by ion exchange chromatography (Whatman CM52) yielded a main fraction which inhibited the growth of Rhodotorula pilimanae and Bacillus megaterium , and was phytotoxic to tobacco and wheat plants. In particular, the injection of this fraction in the culm of wheat plants caused phytotoxic symptoms on leaves similar to those caused in nature by the pathogen. The further purification by HPLC of the above fraction gave rise to four main bioactive substances which have been identified by spectroscopic methods (FAB-MS) and amino acid analysis as syringomycin E, syringomycin G, syringopeptin 25A and syringopeptin 25B, toxic lipodepsipeptides thus far recognized to be produced by most strains of P. syringae pv. syringae . The injection of both syringomycin E and syringopeptin 25A in wheat leaves caused necrotic symptoms; however, syringopeptin 25A was at least six times more active than syringomycin E. The possible role of the toxins in the disease development on cereals and the need for a careful examination of pathogenetic and biochemical features of P. syringae pv. atrofaciens to establish the relationships of the two pathovars in the 'syringae group' are discussed. 相似文献
Purification of bioactive culture extracts of a highly virulent strain by ion exchange chromatography (Whatman CM52) yielded a main fraction which inhibited the growth of Rhodotorula pilimanae and Bacillus megaterium , and was phytotoxic to tobacco and wheat plants. In particular, the injection of this fraction in the culm of wheat plants caused phytotoxic symptoms on leaves similar to those caused in nature by the pathogen. The further purification by HPLC of the above fraction gave rise to four main bioactive substances which have been identified by spectroscopic methods (FAB-MS) and amino acid analysis as syringomycin E, syringomycin G, syringopeptin 25A and syringopeptin 25B, toxic lipodepsipeptides thus far recognized to be produced by most strains of P. syringae pv. syringae . The injection of both syringomycin E and syringopeptin 25A in wheat leaves caused necrotic symptoms; however, syringopeptin 25A was at least six times more active than syringomycin E. The possible role of the toxins in the disease development on cereals and the need for a careful examination of pathogenetic and biochemical features of P. syringae pv. atrofaciens to establish the relationships of the two pathovars in the 'syringae group' are discussed. 相似文献
76.
4株鸭源肠球菌的鉴定和致病性 总被引:1,自引:2,他引:1
对临床分离的4株鸭源肠球菌郑1株、郑2株、郑3株、北京株和1株粪肠球菌参考菌株进行了系统鉴定,并用SDS-PAGE和Western-blot技术对各菌株细胞壁蛋白图谱进行比较分析。结果5个菌株的形态、染色、生理生化特性均与粪肠球菌特性一致;它们均对青霉素、万古霉素和庆大霉素敏感而对四环素耐药;5个菌株人工感染雏鸭及小白鼠均有致病性,但各菌株间致病力存在差异,北京株最强,参考株最弱,其余3株介于北京株和参考株之间;各菌株的细胞壁蛋白经SDS-PAGE在相对分子质量33 370~131 690之间均显示数十条蛋白带,其中郑2株和北京株在相对分子质量66 840处均有1条染色较深的蛋白带,而用Western-blot分析显示抗北京株胞壁蛋白抗体只能检测到北京株相对分子质量为66 840的抗原蛋白。以上结果表明,这5个被检菌株为致病性粪肠球菌,且致病性以北京株最强。 相似文献
77.
不同光增方式和周期对蛋鸡蛋品质和血液生化指标的影响 总被引:1,自引:0,他引:1
研究光增方式和光照周期对蛋鸡蛋品质和血液生化指标的影响。将20周龄海兰褐商品蛋鸡320只,随机分为8组,每组4个重复,每个重复10只鸡。试验光照周期采用渐增和骤增2种,光周期设11L∶13D、13L∶11D、15L∶9D、17L∶7D4个水平。结果表明:①不同光增方式对蛋形指数和哈氏单位有显著影响(P<0.05),以渐增条件下较好。不同光增方式对血液生化指标没有显著影响(P>0.05)。②不同光照周期对蛋黄颜色有显著影响(P<0.05),以15L∶9D处理组蛋黄颜色最好。不同光照周期对血液生化指标有一定影响,以13L∶11D处理组较好。 相似文献
78.
采用白细胞介素-6依赖细胞株B9建立了鸡白细胞介素-6活性的MTT检测方法。每孔培养细胞数在2.5×103~4×104范围内D值与细胞数显示有良好的线性关系,MTT的最佳保留时间为4 h,最低检测限为0.1 U/mL。应用该方法检测了健康艾维茵肉鸡25例,血清chIL-6活性为(4.33±0.75)U/mL,而25例葡萄球菌病患鸡血清chIL-6的活性为(14.05±6.87)U/mL,与健康肉鸡比较差异极显著(P<0.01),为该方法进一步临床应用奠定了基础。 相似文献
79.
AIM: To investigate the potential of murine epidermal stem cell (ESC) differentiation after seeded in a biodegradable carrier and implanted subcutaneously into syngeneic recipient mice. METHODS: ES cells were induced in vitro to differentiate into ESCs. After stained with a fluorescent dye Hoechst 33342, these ESCs were seeded into a polyglycolic acid (PGA) net containing collagen gel, functioning as a cell carrier, and implanted subcutaneously into 129/J mice, which were syngeneic to these stem cells. RESULTS: The ESCs kept alive in the implant when observed under a fluorescent microscopy 3 weeks or longer after implantation, and could differentiate into hair follicle-like structure, glandular structure, and gave rise to additional structures displaying features resembling native dermis. No apparent rejection or severe side effects were observed at least 10 weeks post-implantation. CONCLUSION: It is feasible to use these ESCs as seed cells in the study to fabricate dermal equivalent having the potential to develop dermal appendages. 相似文献
80.
不同颜色果袋对李果实着色及花色素苷合成的影响因素分析 总被引:2,自引:2,他引:2
以大石早生李为试材,研究了不同颜色的果袋对李(Prunus salicina Lindl.)果实外观色泽、花色素苷含量的影响,并探讨了果实中糖酸含量、PAL(苯丙氨酸氨解酶)和UFGT(类黄酮葡糖苷转移酶)酶活性与花色素苷合成的关系。结果表明,果袋的透光率与果皮外观色泽有密切关系,透光率越高,a*越大,果皮颜色越红。白色果袋与对照、红袋与黄袋果实外观无显著差异,白袋与红袋,黑袋(完全不透光)与黄袋,红袋与黄袋处理之间的果实外观色泽存在显著差异。果实成熟时果皮中花色素苷含量与纸袋的透光率呈正比,波长580nm以上橙、红光的透光率与果皮中花色素苷含量相关系数r>0.99。在不同颜色果袋影响果实成熟时果皮的糖酸积累方面:不同颜色果袋对果肉中糖酸含量无显著影响,果皮的糖含量与花色素苷含量亦无显著相关性,但成熟时果皮中酸含量与花色素苷含量呈显著正相关(r=0.9815*)。不同颜色果袋影响PAL、UFGT酶活性,果实成熟时不同果袋PAL酶活性与花色素苷含量相关性显著(r=0.9613*),UFGT酶活性与花色素苷含量相关性显著(r=0.9365*)。 相似文献