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71.
马立克氏病的发病机理及马立克氏病疫苗的免疫机理 总被引:2,自引:1,他引:2
本文综述了马立克氏病(MD)的发病机理和MD疫苗的免疫机制,表明IFN-γ的NO在MD致病机理中具有重要作用,它们在MDV溶细胞感染过程和潜伏感染过程中抑制了病毒的复制;特异性和非特异性免疫反应参与了疫苗免疫的过程,细胞毒性T细胞(CTLs)在特异性免疫反应中具有特别重要的作用。 相似文献
72.
猪瘟、猪伪狂犬病一直危害着我国的养猪业,为提高猪群对这两病的抵抗力,减少经济损失,浙江加华种猪有限公司通过抗体水平检测及合格率分析,确定了本场猪瘟、猪伪狂犬病科学、合理的免疫接种程序。 相似文献
73.
本文在调查研究凉山草坪病虫害的基础上,对草坪的病虫害防治进行了初步探讨和研究,并提出了解决途径. 相似文献
74.
本项研究于2000年5月—2001年5月从内蒙古锡林郭勒盟地区,不同草原景现带牛、羊体表和草地采集草原血蝉1800只,用直接荧光抗体法检查蜱带菌情况,带菌率为7.5%(6/80)。晴视野显微镜检查蜱带菌情况,带菌率为2%(2/100);用间接荧光法进行血清流行病学调查,结果证实,调查点的牛和野鼠均存在莱姆病螺旋体感染,其感染率分别为10%和20%,都高于当地人群平均感染率(7.09%),上述研究证实内蒙古锡林郭勒盟地区人畜及野生动物均有莱姆病螺旋体感染。 相似文献
75.
Dutch dairy herds closed for at least 3 years with no history of paratuberculosis were recruited for a study on herd-certification. One hundred dairy herds were tested for Mycobacterium paratuberculosis at 6-month intervals by pooled faecal culture (five individual animal samples per pool) with solid media. Ninety of the herds completed 9 herd tests and 10 herds dropped out of the study for reasons other than a paratuberculosis diagnosis. Of the 90 herds completing the full study, 61% eventually were found to be M. paratuberculosis-infected. The number of infected herds detected decreased with each round of testing. Assuming that all infected herds had been detected by the ninth herd test, the observed percentage of herds that were truly noninfected (P-free) after each round of testing was calculated. The observed P-free was compared to the predicted P-free based on a previously reported herd-certification model. The P-free predicted by the model was significantly different from the observed P-free. When a single assumption in the model was changed and a diagnostic sensitivity of 40–50% was selected, the predicted P-free closely approximated the observed P-free for the 90 Dutch dairy herds studied. The critical assumption that was changed for Version 2.0 of the model was within-herd infection prevalence for infected but test-negative herds after each round of serial testing. Model Version 1.0 had assumed a 50% decrease in within-herd prevalence but Version 2.0 assumed a stable within-herd prevalence. Culture of pooled faecal samples provides a high-sensitive, high-specific, low-cost test for herd-certification programs. 相似文献
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78.
Nagaraja R. Thirumalapura Willard Feria Eric Hue Corey Zellers Deepanker Tewari 《Journal of veterinary diagnostic investigation》2021,33(2):375
Johne’s disease (paratuberculosis) is an economically important disease of cattle worldwide. The disease is caused by Mycobacterium avium subsp. paratuberculosis (MAP), a fastidious gram-positive bacterium. PCR is increasingly used in diagnostic laboratories for the detection of MAP in fecal samples given the rapid test turnaround time and sensitivity and specificity comparable to fecal culture. However, efficient extraction of DNA for sensitive detection of MAP by PCR is affected by the complex lipid-rich cell wall of MAP and the presence of PCR inhibitors in feces. We evaluated a high-throughput nucleic acid extraction method (MagMAX core nucleic acid purification kit with mechanical lysis module) in conjunction with an hspX gene PCR for the detection of MAP from bovine fecal samples, which resulted in correct identification of all negative (13 of 13) and positive (35 of 35) proficiency test samples obtained from the National Veterinary Services Laboratories. In addition, all 6 negative and 50 of 51 positive diagnostic specimens tested were categorized correctly. 相似文献
79.
《Veterinary anaesthesia and analgesia》2023,50(5):446-458
ObjectiveBedinvetmab, a fully canine anti-nerve growth factor monoclonal antibody, was evaluated in dogs for control of osteoarthritis-related pain in a study conducted to support registration in the USA.Study designRandomized, double-blind, placebo-controlled, multicenter, parallel-group study.AnimalsGeneral practice client-owned dogs with osteoarthritis (n = 272).MethodsDogs were block randomized 1:1 to placebo (saline, n = 137) or bedinvetmab (n = 135; 0.5–1.0 mg kg–1) administered subcutaneously, once monthly. The primary end point, day 28 Canine Brief Pain Inventory (CBPI) treatment success (TS), required pain severity score (PSS; 0–10) decrease ≥1 and pain interference score (PIS; 0–10) decrease ≥ 2. CBPI TS rates [and number needed to treat (NNT)], change in scores [and standardized effect size (ES)], change in quality of life (QoL) and bedinvetmab half-life were calculated.ResultsSignificant (p < 0.05) improvement with bedinvetmab over placebo occurred (days 28, 42, 56, 84) for CBPI TS. Of cases evaluable for day 28 CBPI TS (placebo, n = 131; bedinvetmab, n = 128), success rates were 36.6% and 47.4%, respectively (p = 0.0410) (NNT, 9.3; PSS and PIS ES, 0.3). CBPI TS increased after the second dose in both groups, plateaued for bedinvetmab at day 42 and decreased for placebo beginning day 84. Day 84 NNT (4.3), PSS (0.4) and PIS (0.5) showed continued improvement with monthly dosing. After the first dose, mean (± standard deviation) bedinvetmab half-life was 19.1 (8.3) days. Adverse events were similar between groups and not considered treatment-related. There was a significant effect of bedinvetmab versus placebo on all CBPI components (PIS, PSS, QoL).Conclusions and clinical relevanceThese results corroborated those previously reported and provide further support of safety and effectiveness of bedinvetmab (0.5–1.0 mg kg–1) administered subcutaneously at monthly intervals to dogs for control of osteoarthritis-related pain. 相似文献
80.
Sera of pigs from élite breeding herds, of boars and sows collected at slaughter-houses, and of pigs from herds known to be infected, were examined for antibody to Aujeszky virus. The conventional and a modified virus-neutralizing antibody (VNA) test and a modified direct complement fixation (CF) test were employed. In simultaneous titrations of positive sera the modified VNA test gave titers approx. 4 log2 units above the titers obtained by the conventional test. The conventional VNA test was found insufficiently sensitive. Unspecific neutralization in the modified VNA test was infrequent in serum dilution 1/2 and rare in dilution 1/4. The GF tests on sera of slaughter sows and animals from known infected herds showed a remarkable consistency with the VNA tests. Inconsistent results were obtained with but few sera. Abt. 5 % of the sera could not be examined because of complement fixation with control antigen. 相似文献