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991.
河北省曲周县景观格局演变及生态服务价值响应研究   总被引:1,自引:1,他引:0  
为对县域土地利用规划与生态保护政策制定提供理论依据,以曲周县为例,依据1985、1999和2012年的土地利用数据,采用景观格局分析法、生态服务价值定量评估法结合相关性及敏感度分析,对曲周县1985—2012年的景观格局、生态服务价值变化以及景观指数对生态服务价值的响应机制进行了探究。结果表明:1)研究期内曲周县景观破碎度和景观异质性增加,景观多样性降低,人类活动对景观格局的影响程度呈加强态势;2)生态服务价值总体减少6 704.11万元,且1999年后生态服务价值衰退速度较之前有所减缓,生态服务价值结构未发生较大变动;3)ESV与SHDI呈正相关,与NP、FN、D和AWMDF呈负相关,同时ESV对NP和FN变化缺乏弹性,对SHDI、D和AWMDF变化反应灵敏。研究认为,曲周县应降低景观的人为干扰力度,加强对景观多样性保护,提高县域整体生态效益。  相似文献   
992.
总结了淮安区气象为农服务工作取得的成效,梳理了存在的问题和薄弱环节,为不断深化和加快发展淮安区气象为农服务提出积极对策。  相似文献   
993.
产蛋白酶枯草芽胞杆菌益生菌种的筛选与应用   总被引:10,自引:0,他引:10  
本研究从健康鸡体内分离、选育出一株可产中性蛋白酶的枯草芽胞杆菌 ;将其作为益生素生产菌种 ,制备了微生态制剂———益生素 ;并对该菌的生物学性状、产酶性状和饲喂效果进行了系统研究。研究表明该枯草芽胞杆菌培养48小时 ,培养液中含蛋白酶活力可达 1 0 32 .56U ml;Bulb C小鼠腹腔注射和海兰白蛋公雏鸡口服试验均表明 ,该菌对动物安全 ;连续传代及体外保存一年生物性状稳定。饲喂实验表明 ,该益生素能明显促进肉用仔鸡的生长发育 ,到实验期末 ,提高肉用仔鸡体重 7.32 % ,肉用仔鸡的累积饲料转化率提高 8.96 %。对肉用仔鸡 ,合适的添加剂量为 0 .1 %(W W) (含H1菌 7.1 0× 1 0 5CFU g饲料 )  相似文献   
994.
兽医中药复方药物动力学研究方法及展望   总被引:1,自引:0,他引:1  
本文概述了兽医中药复方药物代谢动力学的研究方法,对今后兽医中药复方药物代谢动力学的研究与发展进行了展望.  相似文献   
995.
The study was based on 70 pig herds in the south-eastern part of Norway during the period from 1984 to 1986. The purpose was to design a health card system based on individual disease records covering diseases in sows, piglets and slaughter pigs. It is concluded that individual health records on a herd basis may well be suited for use in epidemiological and genetical studies of disease frequencies and disease resistance. Feedback of results to farmers and veterinarians seems to be important for satisfactory follow-up in the herds.  相似文献   
996.
Endotoxin was detected by the LAL test in the plasma of swine and cattle following in vivo injection of endotoxin in order to evaluate the applicability of the test in veterinary medicine for detection of endotoxemia.Clinical symptoms of endotoxemia occurred after the injection into 3 swine of 0.10–0.25 mg endotoxin/100 kg bwt and after the infusion during 1–1½ h of 2.0–2.2 mg endotoxin/100 kg bwt into 3 calves. The concentration of endotoxin detected by the LAL test in the experimental animals ranged from 0.15 ng to 6.0 ng endotoxin per ml crude plasma. As positive LAL reactions were obtained only in close connection to the administration of endotoxin, clearance of endotoxin to levels below the sensitivity of the test was fast. In spite of the fast clearance, light symptoms of endotoxemia could be seen as long as 24 h after the last sample showing a positive test result. The applied technique for LAL analysis on blood, therefore, was not adequate for detection of endotoxin at sufficiently low concentrations and some possibilities of improving the technique are discussed.Though leukocytosis were found not to influence the outcome of the LAL test on blood, leukocytic mediators released by endotoxin or endotoxin-derived injuries may still have caused the persistence of the symptoms of endotoxemia, and this question is disputed in relation to the benefit of improving the technique.Especielly in the veterinary clinic, great precautions are necessary to obviate false positive test samples resulting from, e.g., external contamination or transient stress caused by excitement, and it is concluded that the possible application of the LAL test for detection of endotoxemia in veterinary medicine is restricted to surveillance of hospitalized animals and to research purposes.  相似文献   
997.
Magnetic resonance imaging (MRI), a noninvasive technique that provides accurate, detailed, anatomic images, has had a major impact in the diagnosis of human disease. This technique is based upon the inherent magnetic properties of certain nuclei. Induction of the nuclei into a low energy state is achieved by placing them in a static magnetic field. The nuclei may then be excited into a high energy state by application of a radio frequency pulse. When the second field is stopped, the nuclei return to ground state and emit the absorbed energy in the form of a radio signal. This signal is received by a coil that generally surrounds the specimen and converted to an anatomic image through a process of computer-assisted reconstruction. Contrast is altered by applying the second pulse in different sequences (saturation recovery, inversion recovery, and spin echo) and using enhancing agents such as gadolinium. In this paper, we present an overview of the general principles of MRI and some clinical examples in dogs and cats with central nervous system disease.  相似文献   
998.
INTRAOPERATIVE RADIOTHERAPY OF CANINE BLADDER CANCER   总被引:2,自引:0,他引:2  
Thirteen dogs had partial surgical extirpation followed by whole bladder intraoperative radiotherapy for urinary bladder cancer. Eleven of the neoplasms were transitional cell carcinomas (five Stage T1, six stage T2); one was rhabdomyosarcoma (Stage T2), and one was leiomyosarcoma (Stage T2). Histopathologic evaluation showed that neoplasia extended to the margins of the excised tissue in at least 11 of the 13 dogs. Radiotherapy from a 137Cs teletherapy machine was applied to the surgically exteriorized bladder, with doses at the 90% isodose level varying from 2188 to 2888 cGy (10 of 13 dogs receiving 2670–2700 cGy). Sixty-one percent of the dogs were alive at 1 year, 30% at 18 months, and 15% at 2 years. From the time of initial clinical signs of bladder neoplasia, 69% of the irradiated dogs were alive at 1 year, 46% at 18 months, and 23% at 2 years (one dog is still living, at 70 months). Of the owner-reported or clinically determined posttherapy complications, there was increased frequency of urination in 46% of the dogs, urinary incontinence in 46%, cystitis in 38%, and stranguria in 15%. Either persistence or recurrence of neoplasia was found in six (46%) of the dogs and metastasis in four (30%), with two of these having both recurrence and metastasis. Qualitative assessment of the complications was not done, but owner-perceived severity of the complications, metastasis, or diagnosed persistence or recurrence of the neoplasm were the major reasons for ultimately killing most of the dogs.  相似文献   
999.
Objective To estimate the time veterinary graduates spend in private practice and in veterinary work generally, and to determine what factors influence this.
Methods Questionnaires were completed in the sixth year after graduation by 119 veterinarians who had participated in this longitudinal study since starting the veterinary course, and the data were analysed using the SAS System for Windows.
Results Of those who started the veterinary course, 90% graduated, and 96% of these then entered private practice. Five years later 94% (73% in full-time equivalents) were working as veterinarians, and 64% (50% in full-time equivalents) were still in private practice in Australia. Hours, attitudes of principals and clients, and inadequate rewards were the main reasons for leaving private practice. The likelihood of being still in private practice was greater for those who had had significant responsibility for animals before they entered the course, but it was not related to geographical origin (city vs country), age at entry or gender. Women were, however, more likely than men to be working part time as veterinarians. Predictions of veterinary working life were not affected by geographical origin or by previous experience with animals or on farms, but men expected to work longer than women.
Conclusion The average veterinary career, estimated by veterinarians who graduated 5 years earlier, is 24 years in fulltime equivalents for men, and 16 years for women. Almost all (94%, representing 73% in full-time equivalents) still work as veterinarians after 5 years, most of them (76%, representing 59% in full-time equivalents) in private practice. The likelihood of remaining in private practice is related to previous responsibility for animals.  相似文献   
1000.
Le test de Habel utilisé dans le monde entier a rendu d'inestimables services. Il continuera à en rendre longtemps encore puisqu'il permet de caractériser de façon simple et rapide un très bon ou un très mauvais vaccin.

Grâce à une interprétation critique et raisonnée des résultats obtenus il est possible de distinguer des vaccins de valeur moyenne ou médiocre mais, dans ce cas, l'imprécision de ce test est grande, ce qui pose à l'expérimentateur des problèmes évidents.

En raison, d'une part de la nécessité d'utiliser un test aussi simple que le test de Habel, mais plus fiable, d'interprétation plus aisée et répondant mieux aux conditions d'utilisation des vaccins préventifs sur le terrain, et d'autre part, de la difficulté à généraliser actuellement tout au moins un test qui implique l'emploi d'un vaccin de référence, il nous semble possible et souhaitable de définir dès maintenant, en tenant compte des travaux antérieurs sur cette question, une technique qui réponde à ces impératifs.  相似文献   

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