全文获取类型
收费全文 | 288篇 |
免费 | 26篇 |
专业分类
林业 | 14篇 |
农学 | 12篇 |
66篇 | |
综合类 | 31篇 |
农作物 | 26篇 |
水产渔业 | 21篇 |
畜牧兽医 | 119篇 |
园艺 | 6篇 |
植物保护 | 19篇 |
出版年
2023年 | 3篇 |
2022年 | 5篇 |
2021年 | 10篇 |
2020年 | 17篇 |
2019年 | 11篇 |
2018年 | 12篇 |
2017年 | 16篇 |
2016年 | 13篇 |
2015年 | 14篇 |
2014年 | 21篇 |
2013年 | 18篇 |
2012年 | 19篇 |
2011年 | 18篇 |
2010年 | 13篇 |
2009年 | 13篇 |
2008年 | 17篇 |
2007年 | 14篇 |
2006年 | 15篇 |
2005年 | 13篇 |
2004年 | 13篇 |
2003年 | 7篇 |
2002年 | 9篇 |
2001年 | 1篇 |
2000年 | 4篇 |
1999年 | 1篇 |
1998年 | 2篇 |
1996年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1974年 | 2篇 |
1972年 | 1篇 |
排序方式: 共有314条查询结果,搜索用时 125 毫秒
41.
Detection of Coxiella burnetii in buffaloes aborted fetuses by IS111 DNA amplification: A preliminary report 总被引:1,自引:0,他引:1
A.G. Perugini F. Capuano A. Esposito C. Marianelli A. Martucciello G. Iovane G. Galiero 《Research in veterinary science》2009,87(2):189-191
The aim of this study was to evaluate by PCR analyses the presence of Coxiella burnetii infection in fetuses of water buffalo (Bubalus bubalis) in the Campania region (Southern Italy). Samples were collected only from aborted fetuses and C. burnetii presence was evaluated by one-tube nested PCR amplification of the IS111 repetitive element. Of the 164 fetuses examined 14 (17.5%) were positive after DNA amplification, showing that C. burnetii occurs in this population of water buffaloes.However, more extensive prevalence studies need to be carried out to define the role of buffaloes as reservoirs for this pathogen and also the role of C. burnetii as an abortive agent in this animal. 相似文献
42.
Valentina Mariani Simona Palermo Silvia Fiorentini Alessandra Lanubile Elisabetta Giuffra 《Veterinary immunology and immunopathology》2009,131(3-4):278-284
The intestinal epithelial cells (IEC) play an important role in the immune system of swine, protecting against infectious and non-infectious environmental insults. The IEC participate in the innate immune response of the intestine through different mechanisms such as barrier function, mucus secretion, antibacterial peptide synthesis and participation in the cytokine/chemokine networks.Most of the current knowledge of intestinal cell functions has come from studies conducted on cell cultures generated from human cancers or from classical animal models. However, because the molecular and cellular elements of the immune system have been selected over evolutionary time in response to the species-specific environment, models of immune function based on mouse and human need to be applied cautiously in pig. Few models of swine small intestine epithelium exist and these are poorly characterised. In the present study we characterised the basal expression of epithelial and immune-related genes of two pig small intestine cell lines, IPEC-J2 and IPI-2I, under different culture conditions. These data represent essential background information for future studies on pig-intestinal pathogen interactions. 相似文献
43.
Comazzi S Gelain ME Spagnolo V Riondato F Guglielmino R Sartorelli P 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(1):47-54
BACKGROUND: In dogs, flow cytometry is used in the phenotyping of immunologic cells and in the diagnosis of hemic neoplasia. However, the paucity of specific antibodies for myeloid cells and B lymphocytes and of labeled antibodies for multicolor techniques limits the ability to detect all leukocyte subpopulations. This is especially true for neoplastic and precursor cells. CD18 and CD45 are expressed on all leukocytes and are involved in cell activation, and together could be useful in helping determine cell lineage. OBJECTIVES: The purpose of this study was to double label canine blood for CD18 and CD45 and to use the differential expression of antigens to identify leukocyte populations in dogs with non-neoplastic and neoplastic hematologic diseases. METHODS: A template was developed using blood samples from 10 clinically healthy dogs and a back-gating technique. Differential leukocyte counts obtained with the template were compared with those obtained by manual and automated methods on blood samples from 17 additional healthy dogs. Blood samples obtained from 9 dogs with non-neoplastic (reactive) hematologic diseases and 27 dogs with hemic neoplasia were double stained for CD18 and CD45 using mouse anticanine CD18 monoclonal antibody (mAb) plus phycoerythrin-conjugated rat anticanine CD45 mAb and fluorescein isothiocyanate-conjugated rabbit antimouse IgG. Hemic neoplasms were diagnosed by cell morphology, and immunophenotypic and cytochemical markers. RESULTS: With the double label, neutrophils, eosinophils, monocytes, and T- and B-lymphocytes were identified. In reactive disorders, a population of activated neutrophils with high CD45 and CD18 expression was detected. In hemic neoplasia, cell lineage was easily determined, even in acute leukemia. CONCLUSIONS: Double labeling for CD18/CD45 may be useful as a screening method to evaluate hematologic diseases and help determine cell lineage, and to aid in the selection of a panel of antibodies that would be useful for further analysis. 相似文献
44.
Maria Antonietta Demontis Santa Olga Cacciola Marcella Orrù Virgilio Balmas Valentina Chessa Bianca Elena Maserti Laura Mascia Francesco Raudino Gaetano Magnano di San Lio Quirico Migheli 《European journal of plant pathology / European Foundation for Plant Pathology》2008,120(4):339-351
Real-time PCR assays based on SYBR? Green I and TaqMan? technologies were developed for in planta detection and quantification of Phoma tracheiphila, the mitosporic fungus causing ‘mal secco’ disease on citrus. Primers and a hybridization probe were designed on the basis
of the internal transcribed spacer (ITS) region of the nuclear rRNA genes. The real-time PCR assays were compared with a classic
isolation method in two separate experiments carried out on 6 and 24 month-old sour orange seedlings, artificially inoculated
with a conidial suspension of the pathogen. Both technologies made it possible to follow the progression of infection by P. tracheiphila, enabling detection and quantification of the target fungus prior to the development of symptoms. The detection limit was
10 copies of the cloned target sequence and 15 pg of genomic DNA extracted from fungal spores. The values of the cycle threshold
(Ct) were linearly correlated with the concentration of the target DNA, indicating that the method is suitable as a qualitative
and quantitative assay. The presence of non-target fungal DNA had no effect on the specificity of the assay, but resulted
in a 10-fold reduction of sensitivity. Total inhibition of the reaction occurred when conidia of the target pathogen were
mixed with an organic soil substrate before extracting DNA using the standard protocol, while an alternative purification
kit resulted in a significant decrease in sensitivity. Compared to classic methods, real-time PCR proved faster and easier
to perform and showed a higher sensitivity. These results suggest that real-time PCR, based on both chemistries, has a great
potential for early diagnosis of ‘mal secco’ disease and for quantitative estimation of fungal growth within host tissue. 相似文献
45.
Antonia Concetta Elia Valentina Ciccotelli Nicole Pacini Ambrosius Josef Martin Dörr Marilena Gili Mauro Natali Laura Gasco Marino Prearo Maria Cesarina Abete 《Fish physiology and biochemistry》2014,40(4):1055-1068
Oxytetracycline (OTC) is employed in fish farms to contest or prevent bacterial infections. We simulated an OTC treatment at therapeutic level (75 mg kg?1) and at higher doses (150, 300 mg kg?1) for 10 days. A withdrawal period of 10 days was considered for treated carp, carrying out the same chemical and biochemical analyses (total glutathione, superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione S-transferase and malondialdehyde). The aim was to obtain data related to the carryover in muscle and on variations in the antioxidant indicators in liver and kidney. The OTC residual levels in muscle showed a dose–response relationship. After 10 days of treatment at the recommended dose (75 mg kg?1), the mean value in muscle was 295 μg kg?1. After 10 withdrawal days, residues in all treated groups were not entirely eliminated by fish. Residues of recommended 75 mg kg?1 OTC dose were lower than the maximum permitted by EEC regulation: 100 μg kg?1. Disturbance in the antioxidant systems in liver and kidney was recorded in (150, 300 mg kg?1) carp, as well as during the withdrawal period. A lowered superoxide dismutase activity and higher levels of catalase, glutathione peroxidase, glutathione reductase and glutathione were evaluated in liver, while in kidney only higher malondialdehyde and glutathione S-transferase concentrations were recorded for 300 mg kg?1 dose. The therapeutic OTC dose exerted lower effects, and only in liver, enhancement of GPx and GR activities was recorded. After the withdrawal period, altered antioxidant responses in tissues were restored for all three OTC doses. 相似文献
46.
Rossetti Antonio Mazzaglia Angelo Muganu Massimo Paolocci Marco Sguizzato Maddalena Esposito Elisabetta Cortesi Rita Balestra Giorgio Mariano 《植物病害和植物保护杂志》2017,124(6):563-575
Journal of Plant Diseases and Protection - Over the last decades, kiwifruit cultivation has gained increasing importance all over the world, but some bacterial diseases seriously threaten its... 相似文献
47.
Staffieri F De Monte V De Marzo C Grasso S Crovace A 《Veterinary anaesthesia and analgesia》2010,37(6):483-490
ObjectiveTo compare the effects of two fractions of inspired oxygen (FiO2) (0.4 and 1) on lung aeration and gas exchange during general anaesthesia in cats.Study designRandomized, blinded, controlled study.AnimalsThirty healthy, mixed breed, client owned female cats.Materials and methodsCats were premedicated intramuscularly with acepromazine (0.03 mg kg?1) and medetomidine (0.015 mg kg?1). Anaesthesia was induced with propofol (5 mg kg?1) and, after orotracheal intubation, maintained with isoflurane carried by either 100% oxygen (G100, n = 15) or an oxygen-air mixture with 40% oxygen (G40, n = 15). All cats were placed in dorsal recumbency and breathed spontaneously throughout the entire procedure. Following surgery (ovariectomy), a spiral computed tomography (CT) of the thorax was performed, arterial oxygen (PaO2) and carbon dioxide (PaCO2) tensions were measured and alveolar-arterial gradient of oxygen [P(A-a)O2] calculated. The CT images were analysed for lung aeration by the analysis of radiograph attenuations (Hounsfield units, HU), according to the following classification: hyperinflated area (-1000 to -900 HU), normally aerated area (-900 to -500 HU), poorly aerated area (-500 to -100 HU) and non-aerated area (-100 to +100 HU). The groups were compared using one-way anova.ResultsCompared to G100, the normally-aerated lung area was significantly greater and the poorly-aerated and non-aerated areas were significantly smaller in G40. PaCO2 was similar in both groups. PaO2 and P(A-a)O2 were significantly higher in G100. In both groups, pulmonary atelectasis developed preferentially in the caudal lung fields.ConclusionIn cats anaesthetised with isoflurane, the administration of an FiO2 of >0.9 significantly impaired lung aeration and gas exchange as compared to an FiO2 of 0.4.Clinical relevanceAn FiO2 of 0.4 may better preserve lung aeration and gas exchange in anaesthetised spontaneously breathing cats but monitoring is essential to ensure oxygenation is adequate. 相似文献
48.
Canopy leaf to fruit ratio (L:F) of 6-year-old ‘Lapins’ sweet cherry trees on Gisela 5 rootstock was manipulated at the end of stage II (38 DAFB) of fruit development. While control trees showed a L:F ratio of 0.7:1 without alteration, on other trees young fruit were manually removed to yield L:F ratios of 2:1 and 3:1, respectively. All leaves and young fruit on trees were counted 30 DAFB. The effect of altering the source–sink ratio of whole trees on sweet cherry fruit quality parameters (fruit increment, fruit mass, color, total soluble solids content, contents of individual sugars and organic acids) was evaluated in the study. High leaf area to fruit (LA:F) ratios influenced significantly darkest fruit color, higher fruit mass, higher total soluble solids content and higher ratio between sugars and acids, which corresponded to better ripening stage. Contents of glucose, fructose and sorbitol, but not sucrose, sum of individual sugars, and the content of malic acid differed significantly among fruit of the different treatments. Fruit of the most advanced maturity stage (treatment 3:1) had the highest quality. Each day of improved L:F ratio counts towards better sweet cherry fruit quality. The results show that low L:F ratio influenced prolonged ripening process and delayed fruit maturity of ‘Lapins’ sweet cherry. 相似文献
49.
Are rhododendron hybrids distinguishable on the basis of morphology and microsatellite polymorphism?
Sequence Tagged Microsatellite Sites (STMSs) and morphological trait markers were used to evaluate 33 rhododendron germplasm for genetic diversity assessment and discrimination power. The average genetic diversity estimates were 0.724 (morphological traits) and 0.174 (STMSs) marker datasets. The Shannon index was higher for morphological traits (1.797) than STMS (0.302). The correlation coefficients obtained by the Mantel matrix correspondence test, which was used to compare the cophenetic matrices for the two markers, showed that estimated values of relationships given for morphological and STMS were not significantly related (p > 0.05). The dataset from STMS, supported by the total probability of identity (1.13 × 10−9) and total paternity exclusion probability (0.9999), allowed all accessions to be uniquely identified. In summary, STMS marker proved to be an efficient tool in assessing the genetic variability among old broad leaf rhododendron genotypes. The pattern of variation appeared to be consistent, and it can be used for germplasm conservation and management for restoration of historical genetic resources. 相似文献
50.