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61.
E Oohashi K Yagi Y Uzuka S Tanabe T Sarashina T Ishida 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(11):1241-1243
The purpose of this study was to evaluate seasonal influences on thyroid hormone levels of healthy outdoor dogs in Hokkaido. We surveyed serum basal total thyroxine (tT4), free thyroxine (fT4), and canine thyroid-stimulating hormone (cTSH) levels, and tT4 levels after administration of TSH for a year. Basal tT4 levels decreased in January, and increased in August and September. fT4 levels increased in January and November. No significant seasonal variation was found in cTSH. tT4 levels after administration of TSH in August and November increased. These results suggested that the thyroid gland may have been activated in November. We should take seasonal variation into consideration when thyroid function is tested. 相似文献
62.
63.
J L Tarigo-Martinie A R Wyatt R M Kaplan 《Journal of the American Veterinary Medical Association》2001,218(12):1957-1960
OBJECTIVE: To determine the prevalence and clinical implications of anthelmintic resistance in cyathostomes of horses. DESIGN: Prospective study. ANIMALS: 80 horses on 10 farms in a 5-county region of northeast Georgia. PROCEDURE: On each farm, horses were stratified in descending order according to pretreatment fecal egg count (FEC), blocked into groups of 4, and then randomly assigned to 1 of 4 treatment groups: no treatment (controls), and treatment with pyrantel pamoate, fenbendazole, or ivermectin. Fecal samples were collected 24 hours prior to treatment and 2, 4, and 6 weeks after treatment for determination of FEC. Mean percentage of reduction in FEC was then calculated for each treatment group. For horses from each farm, the efficacy of each anthelmintic was categorized on the basis of mean percentage of reduction in FEC at 2 weeks after treatment (< 80% reduction = ineffective; 80 to 90% reduction = equivocal; and > 90% reduction = effective). RESULTS: Pyrantel pamoate was effective at reducing FEC in horses from 7 farms, ineffective in horses from 2 farms, and equivocal in horses from 1 farm. Fenbendazole was ineffective at reducing FEC in horses from 9 farms and equivocal in horses from 1 farm. Ivermectin was effective at reducing FEC in horses from all 10 farms. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that cyathostome resistance to fenbendazole is highly prevalent, and resistance to pyrantel pamoate is high enough to warrant concern. Resistance to ivermectin was not detected. On the basis of these data, it appears that ivermectin continues to be fully effective in horses. However, too few farms were used in this study to determine the prevalence of cyathostome resistance to ivermectin. Therefore, the efficacy of ivermectin should continue to be monitored closely. 相似文献
64.
有机微量元素具有多种优点,本文阐述了有关外源微量元素生物学利用率,回顾了微量元素不同添加方法的研究成果并进行比较。1影响动物对微量元素吸收的因素微量元素的吸收水平直接影响动物机体对微量元素的利用。如果饲喂量超过机体的代谢量,微量元素的吸收下降;如果饲喂量不足,机体则会提高对微量元素的吸收,这就说明机体自我平衡作用可以调节营养素的吸收。日粮总体消化率及各营养素间的相互作用均会影响矿物质吸收,这种相互作用包括协同作用(如铁和维生素C)和拮抗作用(如钙和锌,铜和钼、硫)。动物种类、品种、年龄、性别等也会影响微量元… 相似文献
65.
L. LANIER 《EPPO Bulletin》1986,16(2):255-263
Les eucalyptus constituent—au moins au meme titre que les genres Pinus et Populus—l'un des genres d'arbres forestiers les plus importants à l'échelle mondiale, et en particulier par l'extension considérable des reboisements (plus de 4 millions d'ha) en régions tropicales, sahéliennes et tempérées chaudes. L'article tente de faire le point sur les problèmes posés par les maladies pouvant gener cet effort de reboisement, notamment en région méditerranéenne, et souligne l'importance et l'avenir des eucalyptus dans cette région. Il est procédéà un inventaire général, à l'échelle mondiale, des maladies des eucalyptus et de l'importance des parasites en cause. Un certain nombre d'entre eux sont étudiés plus en détail, selon qu'ils sont présents dans le pays d'origine des eucalyptus ou dans les zones où ils ont été introduits. Une section est réservée à la région méditerranéenne, où certaines maladies s'en prenant aux racines, aux rameaux, aux feuilles ou au bois ont été identifiées; pour l'instant, la plupart d'entre elles ne sont pas trop graves. Enfin, des propositions et des règles de protection phytosanitaire, visant à restreindre les risques d'introduction des parasites les plus dangereux ou d'extension de ceux existant actuellement, sont citées, en insistant sur les risques de transport de maladies d'une région à une autre par l'intermédiaire des échanges de matériel végétal autres que les graines. 相似文献
66.
67.
To determine whether turkey herpesvirus (HVT) impairs the aspecific and specific defense against an avian pneumovirus (APV) infection, specific-pathogen-free turkeys were inoculated at 7 days of age with HVT and 1, 5, or 7 wk later with APV. Clinical signs, APV replication, and development of antibodies against APV were evaluated. No differences were found between the birds that received both HVT and APV and those that received only APV. 相似文献
68.
M D Pérez Alenza E Tabanera L Pe?a 《Journal of the American Veterinary Medical Association》2001,219(8):1110-1114
OBJECTIVE: To determine epidemiologic, clinical, and pathologic characteristics of inflammatory mammary carcinoma (IC) in dogs. DESIGN: Retrospective study. ANIMALS: 33 dogs with IC and 153 dogs with malignant mammary tumors other than IC. PROCEDURES: Medical records were reviewed, and signalment, history, physical examination findings, and results of thoracic radiography and necropsy were obtained. RESULTS: 33 of 436 (7.6%) dogs examined at a veterinary teaching hospital because of dysplasia or tumors of the mammary glands and 33 of 186 (17.7%) dogs with at least 1 malignant tumor had IC. Thirty-two of the 33 dogs were sexually intact. Dogs with IC were significantly older than were dogs with other malignant mammary tumors, and in dogs with IC, the tumor was initially noticed a mean of 52 days after the beginning of the last observed estrus, whereas in dogs with other mammary tumors, the tumor was initially noticed a mean of 137 days after the beginning of the last observed estrus. Dogs with IC were more likely to be anorectic and to have generalized weakness, weight loss, and thoracic metastases. Dogs with IC survived a mean of 25 days with palliative treatment. Histologically, involvement of dermal lymphatic vessels was identified in 14 of 19 (74%) dogs with IC. Two clinical forms of IC (primary and secondary) were identified. Dogs with primary IC had a worse clinical condition. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that IC is an uncommon but distinct entity in dogs. A histologic finding of dermal lymphatic involvement should be considered a hallmark for the pathologic diagnosis of IC in dogs. 相似文献
69.
鸽新城疫又称鸽瘟或鸽Ⅰ型副粘病毒病 ,是由鸽Ⅰ型副粘病毒引起的一种高度接触性、败血型传染病。主要表现为腹泻、神经紊乱、呼吸困难及浆膜、粘膜出血等 ;鸽大肠杆菌病是由大肠埃希氏杆菌感染所引起的局部或全身性感染的疾病。若新城疫和大肠杆菌并发 ,将给养鸽爱好者以很大的经济损失和精神打击。现将本人在临床上遇到的两起病例介绍给大家 ,以供参考。1发病情况2003年5月初 ,平顶山市郊西信鸽爱好者相继到我中心 ,叙述了其200多只信鸽参赛后大群出现拉稀、精神不振 ,个别眼流泪 ,有神经症状 ,用氟哌酸、阿莫西林、痢特灵、氯霉素治疗 ,… 相似文献
70.