全文获取类型
收费全文 | 162篇 |
免费 | 9篇 |
专业分类
林业 | 16篇 |
农学 | 1篇 |
基础科学 | 4篇 |
30篇 | |
综合类 | 4篇 |
农作物 | 11篇 |
水产渔业 | 24篇 |
畜牧兽医 | 57篇 |
园艺 | 7篇 |
植物保护 | 17篇 |
出版年
2023年 | 3篇 |
2022年 | 2篇 |
2021年 | 3篇 |
2020年 | 6篇 |
2019年 | 3篇 |
2018年 | 7篇 |
2017年 | 8篇 |
2016年 | 9篇 |
2015年 | 6篇 |
2014年 | 7篇 |
2013年 | 16篇 |
2012年 | 15篇 |
2011年 | 13篇 |
2010年 | 12篇 |
2009年 | 12篇 |
2008年 | 8篇 |
2007年 | 9篇 |
2006年 | 11篇 |
2005年 | 5篇 |
2004年 | 2篇 |
2003年 | 2篇 |
2002年 | 5篇 |
2001年 | 2篇 |
1998年 | 1篇 |
1995年 | 1篇 |
1969年 | 2篇 |
1968年 | 1篇 |
排序方式: 共有171条查询结果,搜索用时 0 毫秒
51.
Akgül Davut Soner Yıldız Murat Güngör Savaş Nurdan Bülbül İzzet Özarslandan Mümine Leon Maela Armengol Josep 《European journal of plant pathology / European Foundation for Plant Pathology》2022,164(1):21-32
European Journal of Plant Pathology - Black-foot (BF) disease of grapevines in nurseries and young vineyards is caused by soil-borne Cylindrocarpon-like asexual morphs. They can be found both in... 相似文献
52.
53.
This study evaluates the multifactorial spatial modelling used to assess vulnerability of the Du¨ zlerc?am?(Antalya) forest ecosystem to climate change.This was done to produce data,to develop tools to support decisionmaking and the management of vulnerable Mediterranean forest ecosystems affected by climate change,and to increase the ability of these forest ecosystems to adapt to global change.Based on regionally averaged future climate assessments and projected climate indicators,both the study site and the western Mediterranean sub-region of Turkey will probably become associated with a drier,hotter,more continental and more water-deficient climate.This analysis holds true for all future scenarios,with the exception of RCP4.5 for the period from 2015 to 2030.However,the present dry-sub humid climate dominating this sub-region and the study area shows a potential for change towards more dry climatology and for it to become semiarid between 2031 and 2050 according to the RCP8.5 high emission scenario.All the observed and estimated results and assessments summarized in this study show clearly that the densest forest ecosystem in the southern part of the study site,characterized by mainly Mediterranean coniferous and some mixed forest and maquis vegetation,will very likely be influenced by medium and high degrees of vulnerability to future environmental degradation,climate change and variability. 相似文献
54.
55.
Karapinar T Dabak M Kizil O 《The Canadian veterinary journal. La revue veterinaire canadienne》2010,51(11):1251-1253
As thiamine status of ruminants is adversely affected by rumen acidity, this study investigated whether or not thiamine deficiency occurs in feedlot cattle fed a high concentrate diet. Fifty 1- to 2-year-old feedlot cattle fed a high concentrate diet (75% barley) for at least 3 mo (high concentrate diet group) and 15 healthy feedlot cattle of similar ages (control group) that were fed a low concentrate diet (30% barley) were used. Rumen fluid samples were obtained by rumenocentesis and their pH was determined with a portable pH meter. Blood samples taken from all animals from a jugular vein were used to determine erythrocyte transketolase enzyme activity, and hence thiamine pyrophosphate (TPP) effect. Odor and mean pH values of ruminal fluid samples from the high concentrate diet and control group were acidic (pH 5.3) and aromatic (pH 6.1), respectively. The mean TPP effect % in the high concentrate diet group (47.2 ± 3.2) was significantly higher than in the control group (19.53 ± 2.5) (P < 0.001). The study provides evidence of a TPP effect in feedlot cattle fed a high concentrate diet. 相似文献
56.
In this study certain biological and prey consumption features of the predator of mealybug, namely Nephus kreissli Fürsch & Uygun (Coleoptera: Coccinellidae), fed on vine mealybug Planococcus ficus (Signoret) (Hemiptera: Pseudococcidae), were determined under the laboratory conditions. Experiments were performed in the acclimatized room under 28?±?1°C, 60?±?10% r.h. and a photoperiod of 16:8 h(L:D) conditions. To determine the biological features of the coccinellid, predator individuals were continuously observed from egg stage to end of adult stage. The development, survival and fecundity of N. kreissli were determined and all the measured data were recorded daily. The total development time from egg to the eclosion of adult stage was determined as 31.6?±?0.4 days. The lifespan of males and females was 66.0?±?3.8 and 65.8?±?3.5 days, respectively; and a single female laid 122.6 eggs. The raw data related to life history were analyzed by using the age-stage, two-sex life table. The intrinsic rate of increase, the net reproductive rate, and the mean generation time were 0.0709?±?0.0036 d?1, 53.1?±?9.5 offspring and 55.8?±?1.3 days, respectively. The first and second instars of N. kreissli preferred egg stages of P. ficus to other stages of mealybug. On the other hand, third and fourth instars and adult predators preferred the second and third instar nymphs and adult females of the prey. It was determined that the egg consumption of N. kreissli increased with the development of larval stages, and that the highest consumption was recorded in its fourth instar. 相似文献
57.
Dabak M Karapinar T Gulacti I Bulut H Kizil O Aydin S 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(3):514-518
BACKGROUND: Bovine viral diarrhea virus (BVDV) infection is one of the causes of hemorrhagic diathesis in cattle but there have been limited field studies about that condition. HYPOTHESIS: To identify the cause of hemorrhagic diathesis in calves and describe its clinical findings. ANIMALS: Five calves from a farm with 150 dairy cows. METHODS: Clinical examination of the calves was performed. After blood samples were obtained from 2 calves, whole blood, sera, and leukocyte samples were used for hematologic and hemostatic examinations, neutralization tests, virus isolation, and viral genome sequencing. RESULTS: The calves had moderate pyrexia, dullness, serous or mucous nasal discharge, and petechial and ecchymotic hemorrhages on mucosal surfaces. Severe thrombocytopenia and anemia were identified on hematologic examinations. All calves died within 10 days of the onset of clinical signs. Virologic examinations identified BVDV as the causative agent of the disease. CONCLUSIONS AND CLINICAL IMPORTANCE: This paper identifies a hemorrhagic syndrome-like disease in calves with bovine viral diarrhea and mucosal disease complex in Turkey. 相似文献
58.
59.
Hulya Turutoglu Mustafa Hasoksuz Dilek Ozturk Murat Yildirim Sonay Sagnak 《Veterinary research communications》2009,33(8):945-956
Although methicillin-resistant Staphylococcus aureus (MRSA) were generally isolated from human beings; these agents were recently isolated from various animal species. It has
been shown that MRSA isolates are not only resistant to beta-lactam antibiotics, but can also be resistant to the other commonly
used antibiotics. In this study, 18 phenotypic methicillin resistant S. aureus isolates from bovine mastitis cases were analyzed by PCR for the presence of mecA gene encoding methicillin resistance and aac(6′)/aph(2″), aph(3′)-IIIa and ant(4′)-Ia genes encoding aminoglycoside resistance. Out of 18 S. aureus isolates (oxacillin MICs, ≥4 μg/ml), 3 were positive for mecA gene. Only one from 3 mecA positive isolates was positive for genes encoding aminoglycoside-modifying enzymes and this isolate carried aac(6′)/aph(2″) in combination with aph(3′)-IIIa gene. The aph(3′)-IIIa gene was detected in 3 isolates. These three isolates carrying the aminoglycoside-modifying enzyme genes were resistant to
gentamicin, kanamycin and neomycin. The mecA gene of 3 MRSA isolates was sequenced. All three mecA genes of these isolates were identical to that found in human MRSA strains, except a one-base substitution at nucleotide
position 757. From the data presented in this study, it can be concluded that MRSA isolated from bovine mastitis may be originated
from human beings, but further studies are needed to investigate the possibility of zoonotic transfer of MRSA. 相似文献
60.
Murat Arslan Konrad Dabrowski Sylvana Ferrer Mariola Dietrich Gustavo Rodriguez 《Aquaculture Research》2013,44(5):760-771
To evaluate protein and lipid requirement of South American catfish surubim (Pseudoplatystoma sp.) juveniles, nine semi‐purified diets containing three levels of protein (40%, 45% and 50%) and three levels of lipid (12%, 16% and 20%) were tested. After 8‐week feeding trial, body weight increase averaged 2124.3 ± 295.7%. Growth performance was significantly affected by dietary level of protein (P < 0.05). At the 40% protein level, increasing level of dietary lipid had a positive effect on final individual mean weight (protein sparing effect). Whole body protein and moisture contents were affected by the dietary level of lipid (P < 0.05). Whole body lipid content positively correlated with the level of dietary lipid (P < 0.05). Cannibalism related mortality was observed despite rearing fish in 24 h dark. Fatty acid composition of fish was affected by the dietary lipid level (P < 0.05). Polyunsaturated fatty acids increased with the increasing level of dietary lipid while saturated fatty acids and monounsaturated fatty acids decreased. Trypsin activity in the digestive tract of surubim was influenced by dietary levels of protein and lipid (P < 0.05). Our preliminary results suggest that the optimum protein/lipid ratio might be close to 45/16% for surubim juveniles. 相似文献