全文获取类型
收费全文 | 228篇 |
免费 | 8篇 |
专业分类
林业 | 12篇 |
农学 | 16篇 |
41篇 | |
综合类 | 5篇 |
农作物 | 1篇 |
水产渔业 | 11篇 |
畜牧兽医 | 135篇 |
园艺 | 5篇 |
植物保护 | 10篇 |
出版年
2022年 | 2篇 |
2021年 | 4篇 |
2019年 | 4篇 |
2018年 | 6篇 |
2017年 | 7篇 |
2016年 | 7篇 |
2015年 | 4篇 |
2014年 | 7篇 |
2013年 | 8篇 |
2012年 | 13篇 |
2011年 | 8篇 |
2010年 | 5篇 |
2009年 | 4篇 |
2008年 | 7篇 |
2007年 | 12篇 |
2006年 | 8篇 |
2005年 | 5篇 |
2004年 | 9篇 |
2003年 | 5篇 |
2002年 | 6篇 |
2001年 | 7篇 |
2000年 | 10篇 |
1999年 | 10篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1992年 | 4篇 |
1991年 | 3篇 |
1990年 | 5篇 |
1989年 | 4篇 |
1988年 | 10篇 |
1987年 | 4篇 |
1986年 | 4篇 |
1985年 | 3篇 |
1984年 | 5篇 |
1983年 | 3篇 |
1982年 | 1篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1976年 | 3篇 |
1975年 | 1篇 |
1974年 | 2篇 |
1972年 | 2篇 |
1971年 | 7篇 |
1970年 | 2篇 |
1969年 | 2篇 |
1968年 | 1篇 |
1967年 | 1篇 |
1966年 | 1篇 |
排序方式: 共有236条查询结果,搜索用时 15 毫秒
1.
The insecticide formulation BI 58 EC was tested for teratogenicity in chicken embryos, with particular reference to degradation of the active ingredient (dimethoate) after the treatment of embryonated eggs. The pesticide was diluted in water to a concentration level of 0.8%, and the emulsion was injected into the air space in a volume of 0.1 ml/egg, or hen's eggs were treated by the immersion technique. Residues of dimethoate were measured in the samples on days, 13, 15 and 19 of the incubation of chicken embryos, and morphological examinations were performed simultaneously. Analytical chemistry data indicated a slower degradation of dimethoate in embryos after the immersion of eggs, and cyllosis was remarkable in this group among the sporadic developmental anomalies. The liver tissues of both treated groups exhibited severe fatty infiltration. 相似文献
2.
The synthesis and secretion of trypsin (trypsin model serine protease) inhibitors are regulated in ovarian follicles by gonadotropins. The superovulation stimulations with 400 IU FSH, 1000 IU PMSG, 1000 IU HCG, 750 IIU PMSG + 750 IU HCG influence in a different way the trypsin inhibiting activities (TIA) of blood plasma (BP) (Figs 1 and 2) and follicular fluid (fig. 3); this points to a possibility of local effects. An increase in the average values of TIA in BP was statistically significant during the whole experiment: P less than 0.05 to P less than 0.001 (following the administration of PMSG+HCG, or PMSG, and HCG); Antisergon administered in 68 hours after PMSG reduced this increase. The changes in the fraction of low-molecular TIA in BP (after BP treatment with perchloric acid) were of converse nature; a decrease in the average values ranged from P less than 0.02 to P less than 0.001 (following PMSG or other stimulations). Antisergon did not influence this decrease. The changes observed on particular days of the trial (Figs. 1 and 2) also indicate different effects of the preparations, mainly of the component LH, which resulted in the occurrence of large nonovulating follicles (greater than 10 mm--"cystic" ones). No such follicles were observed in nonstimulated ewes and after FSH stimulation. The administration of antisergon (goat's antiserum against PMSG) 68 hours after PMSG administration did not prevent their creation. The TIA of follicular fluid (FF) of antral follicles was on average tenfold in comparison with that of blood plasma; and the TIA FF of follicles greater than 10 mm was higher (up to P less than 0.001) than the TIA FF of follicles less than 10 mm. The administration of Antisergon in shorter intervals following PMSG administration (12, 24, 48 and 58 hours) influenced the average values of TIA BP in 120 hours (since PMSG administration) in dependence on time (Tab. I). The effects of Antisergon administered in 12 and 24 hours after PMSG administration on the TIA BP were insignificant if it was administered in 48 and 58 hours the TIA BP increased (P less than 0.02; P less than 0.001) in comparison with the interval of 12 hours. The TIA FF of follicles less than 5 mm, 5-10 mm and greater than 10 mm varied in dependence on the time intervals of Antisergon administration (Fig. 4). The statistical significance of these changes in shown in Tab. II.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
3.
4.
Radiodiagnostic methods have not been used previously for studying the anatomy and diseases of the swimbladder of freshwater fish species. In this study, the radiographic anatomy of the swimbladder and species-related differences in swimbladder structure were studied on plain radiographs taken of 12 Hungarian fish species of major economic importance. Changes observed by radiography were also studied by conventional parasitological methods. The radiodiagnostic method reported here appears to be a useful complement to diagnostic examinations that have been based merely on dissection so far. It enables evaluation of the pathological lesions in live condition, without causing damage to the fish. 相似文献
5.
During a five-year survey including studies on the parasite fauna of bream (Abramis brama), four gill-parasitic Myxobolus species (M. bramae, M. hungaricus, M. impressus and M. macrocapsularis) were recorded in a total of 313 breams from Lake Balaton. The commonest species, M. bramae showed a prevalence of 33%, while the other species occurred sporadically. Myxobolus bramae and M. macrocapsularis infected the tips of the gill filaments and caused both intralamellar and interlamellar infection. Intralamellar plasmodia of small size developed in the capillary network of the gill lamellae whereas the much larger interlamellar plasmodia were formed in the arteria afferens. The intralamellar plasmodia of M. hungaricus always infected the basal or central part of the gill filaments. In contrast to the above species developing in the blood vessels, M. impressus proved to be an epithelial parasite, as its plasmodia always developed in the adjacent gill filaments of two opposite haemibranchia, in the stratified epithelium between the respiratory plates, causing changes of the haemibranchium which were well visible even by the naked eye. 相似文献
6.
7.
8.
The weight of internal organs (swimbladder, kidney, liver, spleen) in relation to the body weight was studied in common carp fingerlings divided into three groups on the basis of swimbladder appearance and microscopic examination of the kidney. The fish had been collected from different Hungarian fish farms at the time when swimbladder inflammation (SBI) usually occurs (in July and August). The first group comprised fish with severe signs of SBI and massive renal sphaerosporosis, the second group consisted of fish with milder swimbladder changes and/or kidney infection by a low number of Sphaerospora renicola, while the third group was constituted by infection-free common carp fry. Statistical analysis of swimbladder, kidney, liver and spleen weight in relation to the body weight revealed that in the infected groups the internal organs were substantially enlarged. This suggests that in common carp fry with SBI the swimbladder changes are accompanied by reno-, hepato- and splenomegaly. 相似文献
9.
Characterisation of Hungarian porcine circovirus 2 genomes associated with PMWS and PDNS cases 总被引:4,自引:0,他引:4
The authors report the data of the first survey on the incidence of post-weaning multisystemic wasting syndrome (PMWS) and porcine dermatitis and nephropathy syndrome (PDNS) in Hungary. A PCR method specific for the detection of porcine circovirus 2 (PCV-2) was developed, which proved to be suitable for diagnostic purposes. PCR screening of organ samples from pigs suspected to be affected with PMWS or PDNS revealed the presence of PCV-2 in 80% of the cases. Six PCV-2 genomes from Hungarian isolates were completely sequenced. Phylogenetic comparison with all the available PCV-2 sequences showed that porcine circoviruses circulating in Hungary are more variable than in several other European countries. Two Hungarian strains clustered together with the Spanish strains forming a distinct group; two others fell in a common group with the French, UK, and Dutch strains, whereas another two strains showed the closest relationship to two of the three known German PCV-2 sequences. 相似文献
10.
Molnár K 《Acta veterinaria Hungarica》2000,48(4):421-432
In a three-year survey of myxosporean infections of the bleak (Alburnus alburnus), involving the examination of 205 fish specimens from the River Danube and 50 from Lake Balaton, four Myxobolus species (two gill parasites, one fin parasite and a species parasitising the skeletal muscles) were detected. Two of the species could be identified as M. alburni and M. obesus. Of the other two species, the gill parasite proved to be a hitherto undescribed species which is described here as a new species by the name of M. margitae. One of the two gill-parasitic species, M. obesus, formed plasmodia in the respiratory lamellae of the gill filaments, while the plasmodia of M. margitae n. sp. were formed in the afferent artery of the primary gill filaments. The plasmodia containing spores morphologically identifiable with the species M. alburni were located in the connective tissue between the fin rays. The less frequently found muscle-parasitic Myxobolus species has not been identified precisely. The plasmodia of M. obesus were found in the fish in May and June, while those of M. alburni and M. margitae n. sp. in July and August. The prevalence of infection in fish examined in these periods was 15.5% for M. obesus, 11.5% for M. margitae and 14.0% for M. alburni. 相似文献