首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   278篇
  免费   7篇
  国内免费   5篇
林业   40篇
农学   16篇
基础科学   2篇
  42篇
综合类   12篇
农作物   29篇
水产渔业   38篇
畜牧兽医   70篇
园艺   14篇
植物保护   27篇
  2024年   1篇
  2023年   2篇
  2022年   11篇
  2021年   13篇
  2020年   15篇
  2019年   15篇
  2018年   13篇
  2017年   13篇
  2016年   13篇
  2015年   12篇
  2014年   8篇
  2013年   22篇
  2012年   19篇
  2011年   25篇
  2010年   19篇
  2009年   13篇
  2008年   11篇
  2007年   9篇
  2006年   6篇
  2005年   6篇
  2004年   7篇
  2003年   11篇
  2002年   3篇
  2001年   3篇
  2000年   6篇
  1999年   1篇
  1998年   1篇
  1997年   1篇
  1996年   3篇
  1995年   1篇
  1994年   1篇
  1991年   1篇
  1985年   1篇
  1980年   1篇
  1979年   1篇
  1974年   1篇
  1972年   1篇
排序方式: 共有290条查询结果,搜索用时 0 毫秒
91.
Fish Physiology and Biochemistry - Recombinant expression system was established for rainbow trout myoglobin (Mb) considering its unique primary structure of having one unusual deletion and two...  相似文献   
92.
This study aims to investigate the effects of dietary garlic powder (25 and 50 g kg?1 feed) supplementation for 6 weeks on lipid and protein oxidation biomarkers in various tissues as well as some blood biochemical parameters in common carp. Based on the present study results, serum malondialdehyde (MDA) concentrations were decreased following garlic supplementation, but the decrease was only significant (P < 0.05) in the group that received 50 g kg?1 dietary garlic compared with the control group. Moreover, garlic at 50 g kg?1 diet caused significant decrease in MDA values of liver and kidney. Additionally, the decreasing effect of garlic at 25 g kg?1 diet on MDA values was only significant in liver. Protein carbonyl contents were only decreased significantly in muscle following garlic administration at 25 g kg?1 diet. Serum aspartate aminotransferase activity decreased significantly in carp that received 25 g kg?1 dietary garlic. Moreover, alkaline phosphatase activity decreased significantly in carp fed diets containing 25 and 50 g kg?1 garlic. On the other hand, garlic supplementation had no significant effect on gamma-glutamyl transferase activity and total protein, albumin, and creatinine concentrations. The results of the present study indicate that garlic powder has potential to decrease oxidative stress to some extent by reducing lipid and protein oxidation in some tissues of common carp.  相似文献   
93.
In this study, the effects of a commercial liquid smoke flavoring agent and two different brining solutions applied on fillets of anchovy were investigated by performing sensory analyses, meat yield, polycyclic aromatic hydrocarbon (PAH) content, and chemical composition analyses. Fillets were brined at 40 and 65% for 4 h at 4°C. Meat yield, sensorial acceptability, and chemical compositions were affected by each brining level. No detectable PAH levels were found in smoke flavoring treated fish samples. Sixty-five percent salt level was rejected by the participants due to high salt content. The results of the study showed that liquid smoke flavoring treatment is applicable to the anchovy fillets, and 40% brining level is recommended.  相似文献   
94.
Animal bites are a major public health problem. The aim of this study was to conduct a survey of animal bites in Bursa, Turkey. Patients who sought medical care for animal bites over an 18-month period were included in our study (n = 1,715). Data were obtained from the registry of the Bursa State Hospital; 71.84% of the patients were men and 28.16% were women. Bites were most frequent among patients who were >18 years of age (comprising 60.83% of all bites). The anatomical site of the bite was recorded in all 1,715 cases, and 1,778 bite locations on the body were reported. The upper extremities were the most frequent sites of animal bites (53.83%), followed by the lower extremities (38.03%). Bites were most frequently inflicted by dogs (68.04%), followed by cats (28.45%), mice (2.56%), and other animals (hamsters, donkeys, horses, foxes, and rabbits together comprised 0.95% of the bites). As a result, bite incidents were mostly associated with males aged >18 years and occurred in the upper extremities. This study showed that dog bites constitute a major animal bite problem in Bursa, Turkey.  相似文献   
95.
Exogenous estrogens used for therapeutic purposes or endogenous estrogen sources such as functional Sertoli cell or ovarian granulosa cell tumors may cause bone marrow toxicity in dogs. The condition is characterized by hematologic abnormalities including thrombocytopenia, anemia, and leukocytosis or leukopenia. Despite intensive therapy with blood or platelet-rich transfusions, broad-spectrum antibiotics, steroids, and bone marrow stimulants, prognosis is unfavorable. Due to the the risk of stimulating the development of uterine diseases and the potential for inducing aplastic anemia, estrogen use in dogs is best avoided where possible. This paper describes the causes of estrogen-induced myelotoxicity, the clinical presentation of the patients, the diagnosis, and the treatment options in the dog.  相似文献   
96.
97.
The ethanol extract of P. kamstchandalis as well as ethyl haematommate, ethyl-2,4-dihydroxy-6-methylbenzoate and methyl-β-orsellinate isolated from it exhibited varying degrees of antibacterial activity.  相似文献   
98.
The replacement value of undecorticated sunflower meal (SFM) in the diets of dairy animals was assessed on-station and on-farm. Eighteen primiparous crossbred (Bos taurus×Bos indicus) cows (350.4±8.84 kg), randomly allocated to three groups, were used in the on-station study. The animals were fed on either a conventional concentrate supplement (control) or on an experimental concentrate, in which SFM replaced 25% (SFM-25) or 50% (SFM-50) of the CP in the control supplement. Green oats (Avena sativa) were supplied ad libitum. A metabolism trial conducted following 60 days of experimental feeding revealed that the intakes of DM, DCP and TDN were similar among the groups. The digestibilities of OM, CP, EE, NDF and ADF were also without significant differences. All the groups were in positive nitrogen balance. Inclusion of SFM at either level had no effect on the intake, excretion or retention of nitrogen. The daily milk yield and its composition did not differ among the dietary treatments. Moreover, the efficiency of utilization of DOM and TDN for FCM production tended to reflect, although non-significantly, increasing levels of SFM inclusion. In the on-farm study, seven multiparous milking buffaloes belonging to six farmers were used to assess the effect of replacing 20% of the CP of the conventional supplement with SFM, in a predominantly crop residue-based diet. The study continued for 4 months and revealed that the average daily feed intake and milk production was similar in the control and SFM-fed groups. It was concluded that SFM can be effectively utilized as a cheaper replacement for costly oil cakes and wheat bran for economic milk production by smallholder farmers.  相似文献   
99.
Basidiospores are implicated in the distribution and genetic diversity of Ganoderma boninense, cause of basal stem rot (BSR) and upper stem rot (USR) of oil palm (Elaeis guineensis). Measurement of aerial basidiospores within plantations in Sumatra showed continuous and high production over 24 h (range c. 2–11 000 spores m?3) with maximum release during early evening. Basidiospores applied to cut surfaces of fronds, peduncles and stems germinated in situ. Equivalent, extensive wounds are created during plantation harvesting and management and represent potential sites for formation of infective heterokaryons following mating of haploid basidiospore germlings. Use of spore‐sized micro‐beads showed that basidiospores could be pulled up to 10 cm into severed xylem vessels, where they are relatively protected from dehydration, UV irradiation and competing microflora. Diversity of isolates from five locations on two plantations was assessed by RAMS fingerprinting. Isolates from within individual palms with USR were identical and represent single infections, but different USR infections had unique band patterns and revealed separate infections. Some BSR‐affected trees contained more than one isolate, and thus had multiple infections. There was one example of adjacent BSR palms with the same isolate, indicating vegetative spread, but there were no identical genets from BSR infections and adjacent fallen palms. Isolate diversity was as great within a plantation as between plantations. It is evident that basidiospores play a major role in spread and genetic variability of G. boninense. Evidence for direct basidiospore infection via cut fronds, indirectly through roots via colonized debris and less frequently, infection by vegetative, clonal spread is considered.  相似文献   
100.
Antibiotic resistance in avian bacterial pathogens is a common problem in the Bangladesh poultry industry. The aim of the present study was to provide information on the present status of antibiotic resistance patterns in avian pathogenic Escherichia coli in Bangladesh. Of 279 dead or sick poultry of different ages, 101 pathogenic E coli strains isolated from broilers and layer hens with colibacillosis infections were screened to determine phenotypic expression of antimicrobial resistance against 13 antibiotics used in both veterinary and human medicine in Bangladesh. Of 101 pathogenic E. coli isolates, more than 55% were resistant to at least one or more of the tested compounds, and 36.6% of the isolates showed multiple-drug-resistant phenotypes. The most common resistances observed were against tetracycline (45.5%), trimethoprim-sulphamethoxazole (26.7%), nalidixic acid (25.7%), ampicillin (25.7%), and streptomycin (20.8%). Resistance to ciprofloxacin (12.9%), chlormaphenicol (8.9%), nitrofurantoin (2%), and gentamicin (2%) was also observed, and none of the isolates were resistant to tigecycline as well as extended spectrum beta-lactamase (ESBL) producers. One isolate was resistant to cefuroxime (1%), cefadroxil (1%), and mecillinam (1%) but was not an ESBL producer. Resistance rates, although significant in Bangladeshi isolates, were found to be lower than those reported for avian isolates from the Republic of Korea and clinical, avian, and environmental isolates from Bangladesh. The high level of antibiotic resistance in avian pathogens from Bangladesh is worrisome and indicates that widespread use of antibiotics as feed additives for growth promotion and disease prevention could have negative implications for human and animal health and the environment.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号