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51.
The effects of ammonia and nitrite on vigour, survival rate, moulting rate of zoea of blue swimming crab, Portunus pelagicus, were studied. A total of five nitrite-N treatments (26.67, 53.34, 106.68, 213.36, 426.72 mg/l) and a control (no nitrite-N added) were
set up for the acute nitrite-N toxicity experiment; a total of five ammonia-N treatments (8.43, 16.86, 33.72, 67.44, 134.88 mg/l)
and a control (no ammonia-N added) were set up for the acute ammonia-N toxicity experiment. The results showed that the vigour,
survival rate and moulting rate of zoea of the blue swimming crabs exposed to over 53.34 mg/l were significantly different
(P < 0.05) from the control group. The zoea LC50 values (mg/l) of nitrite-N were 179.47, 76.56, 66.70, 37.49, 25.01, 25.35, 25.34 mg/l for 24, 36, 48, 60, 72, 84, 96 h, respectively.
The vigour, survival rate and moulting rate of zoea of the blue swimming crabs exposed to over 16.86 mg/l were significantly
different (P < 0.05) from the control group. The zoea LC50 values (mg/l) of ammonia-N were 51.04, 39.62, 38.72, 24.43, 16.90, 13.42, 11.16 mg/l for 24, 36, 48, 60, 72, 84, 96 h, respectively.
The zoeae are highly sensitive to ammonia and nitrite, and the toxicity of ammonia and nitrite on Portunus pelagicus decrease with development of this crab. 相似文献
52.
53.
Bianca Ferreira Olivieri Camila Urbano Braz Fernando Brito Lopes Elisa Peripolli Rafael Medeiros de Oliveira Silva Rosana Ruegger Pereira da Silva Corte Lucia Galvo de Albuquerque Anglica Simone Cravo Pereira Nedenia Bonvino Stafuzza Fernando Baldi 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2021,138(1):80-90
The aim of this study was to identify differentially expressed genes (DEG) in the Longissimus thoracis muscle of Nelore cattle related to fatty acid (FA) profile through RNA sequencing and principal component analysis (PCA). Two groups of 10 animals each were selected containing PC1 and PC2 extreme DEG values (HIGH × LOW) for each FA group. The intramuscular fat (IMF) was compared between cluster groups by ANOVA, and only the sum of monounsaturated FA (MUFA) and ω3 showed significant differences (p < .05). Interestingly, the highest percentage (95%) of phenotypic variation explained by the sum of the first two PC was observed for ω3, which also displayed the lowest number of DEG (n = 1). The lowest percentage (59%) was observed for MUFA, which also revealed the largest number of DEG (n = 66). Since only MUFA and ω3 exhibited significant differences between cluster groups, we can conclude that the differences observed for the remaining groups are not due to the percentage of IMF. Several genes that have been previously associated with meat quality and FA traits were identified as DEG in this study. The functional analysis revealed one KEGG pathway and eight GO terms as significant (p < .05), in which we highlighted the purine metabolism, glycolytic process, adenosine triphosphate binding and bone development. These results strongly contribute to the knowledge of the biological mechanisms involved in meat FA profile of Nelore cattle. 相似文献
54.
FEASIBILITY FOR USING HYPOFRACTIONATED STEREOTACTIC VOLUMETRIC MODULATED ARC RADIOTHERAPY (VMAT) WITH ADAPTIVE PLANNING FOR TREATMENT OF THYMOMA IN RABBITS: 15 CASES
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Mario Dolera Luca Malfassi Giovanni Mazza Gaetano Urso Massimo Sala Silvia Marcarini Nancy Carrara Simone Pavesi Sara Finesso Michael S. Kent 《Veterinary radiology & ultrasound》2016,57(3):313-320
Thymoma is a relatively common tumor in rabbits. Treatment with surgery, radiation therapy, and chemotherapy alone or in combination has been reported with varying outcomes. Stereotactic volumetric modulated arc radiotherapy delivered in a hypofractionated manner allows high doses of radiation to be delivered to the target volume while allowing sparing of adjacent critical structures. This therapy is ideally suited for thymomas in rabbits given their size, the difficulty of multiple anesthesia episodes and the complexity of the radiotherapy plans required due to the tumor's proximity to the heart, lungs, and mediastinal structures. Fifteen rabbits with thymoma were prospectively recruited for this observational, single institution, single arm clinical study. All rabbits were imaged with both computed tomography (CT) and magnetic resonance imaging (MRI). A total dose of 40 Gy in six fractions was delivered using a single arc over an 11‐day period with repeat CT simulation done every other fraction for adaptive planning. Follow‐up evaluation was done through repeat CT and MRI imaging and revealed complete responses using the Response Evaluation Criteria in Solid Tumors (RECIST) criteria. Two rabbits had died at 618 and 718 days, 10 were alive and three were lost to follow‐up. Observed acute and late effects were graded according to the Veterinary Radiation Therapy Oncology Group (VRTOG) criteria and were found to be minimal. 相似文献
55.
Amália Turner Giannico Elaine Mayumi Ueno Gil Daniela Aparecida Ayres Garcia Marlos Gonçalves Sousa Tilde Rodrigues Froes 《Veterinary research communications》2016,40(1):11-19
The aim of this study was to develop regression models for correlation of canine fetal heart development with body size to characterize normal development or suggest cardiac anomalies. Twenty clinically healthy pregnant bitches, either brachycephalic and non-brachycephalic, were examined ultrasonographically. Transabdominal fetal echocardiography was conducted every 4 days from the beginning of cardiac chambers differentiation until parturition. Ten cardiac parameters were measured: length, width and diameter of the heart; heart area; left and right ventricular dimensions; left and right atrial dimensions; and aortic and pulmonary artery diameter. Femoral length, biparietal diameter and abdominal cross-sectional area were also recorded. Regression equations were developed for each parameter of fetal body size, and linear and logarithmic models were compared. The model with the highest correlation coefficient was chosen to produce equations to calculate relative dimensions based on the correlations. Only the left-ventricular chamber differed between the two racial groups. Biparietal diameter was the independent parameter that produced the highest correlation coefficient for the most fetal cardiac dimensions, although good correlations were also observed using femoral length and abdominal cross-sectional area. Heart width and heart diameter were used as surrogates of cardiac development, as these measurements showed the best statistical correlation. Quantitative evaluation of fetal cardiac structures can be used to monitor normal and abnormal cardiac development. 相似文献
56.
Chiara Gomiero Giulia Bertolutti Tiziana Martinello Nathalie Van Bruaene Sarah Y. Broeckx Marco Patruno Jan H. Spaas 《Veterinary research communications》2016,40(1):39-48
Tendons regenerate poorly due to a dense extracellular matrix and low cellularity. Cellular therapies aim to improve tendon repair using mesenchymal stem cells and tenocytes; however, a current limitation is the low proliferative potential of tenocytes in cases of severe trauma. The purpose of this study was to develop a method useful in veterinary medicine to improve the differentiation of Peripheral Blood equine mesenchymal stem cells (PB-MSCs) into tenocytes. PB-MSCs were used to study the effects of the addition of some growth factors (GFs) as TGFβ3 (transforming growth factor), EGF2 (Epidermal growth factor), bFGF2 (Fibroblast growth factor) and IGF-1 (insulin-like growth factor) in presence or without Low Level Laser Technology (LLLT) on the mRNA expression levels of genes important in the tenogenic induction as Early Growth Response Protein-1 (EGR1), Tenascin (TNC) and Decorin (DCN). The singular addition of GFs did not show any influence on the mRNA expression of tenogenic genes whereas the specific combinations that arrested cell proliferation in favour of differentiation were the following: bFGF2 + TGFβ3 and bFGF2 + TGFβ3 + LLLT. Indeed, the supplement of bFGF2 and TGFβ3 significantly upregulated the expression of Early Growth Response Protein-1 and Decorin, while the use of LLLT induced a significant increase of Tenascin C levels. In conclusion, the present study might furnish significant suggestions for developing an efficient approach for tenocyte induction since the external administration of bFGF2 and TGFβ3, along with LLLT, influences the differentiation of PB-MSCs towards the tenogenic fate. 相似文献
57.
58.
Galina P. Simeonova Svetozar Z. Krastev Radostin S. Simeonov 《Veterinary research communications》2016,40(3-4):107-115
Background
The pathogenic mechanism of equine recurrent uveitis (ERU) is still poorly defined and many variations between experimental animal models and spontaneous disease exist.Objectives
The aim of our study was to investigate if Th17 cell-mediated response plays role in the pathogenesis of the used experimental model in horses and to reveal its pathological findings.Methods
Experimental uveitis was induced in 6 healthy horses. The concentrations of retinal autoantigen CRALBP and IL-17 were measured using ELISA in aqueous humor and vitreous body of the 12 inflamed eyes as well as in 12 control non-inflamed eyes taken from 6 horses in slaughter house. After centrifugation of the two eye media, smears were prepared and cytological investigation was performed. Tissue specimens were taken from all eye globes and were submitted to histopathological investigation.Results
CRALBP and IL-17 concentrations were significantly elevated in eye media of horses with experimental uveitis in comparison with controls. Cytological and histopathological findings corresponded to the changes characteristic of chronic immune-mediated inflammation with mononuclear cell infiltration of uvea, choroid, retina, and eye media as well as severe retinal destruction.Conclusions
Our study demonstrated the involvement of the retinal autoantigen CRALBP as well as IL-17 in the pathogenesis of experimental uveitis in horses. These findings suggests that this experimental uveitis in horses may serve as a suitable animal model for investigation of IL-17- mediated immune response during spontaneous autoimmune uveitis in horses as well as in humans.59.
60.
Maurizio Annoni Simone Borgonovo Marina Aralla 《Veterinary and comparative oncology》2023,21(3):469-481
Several sentinel lymph node (SLN) mapping techniques, to detect nodal metastasis in canine tumours have been investigated in the last 10 years in veterinary oncology. The purpose of this prospective study was to describe a reliable, quick, and inexpensive technique for SLN mapping in canine patients affected by cutaneous and subcutaneous mast cell tumours (MCT). Eighty dogs were enrolled in this study for a total of 138 cytologically diagnosed MCTs. Sentinel lymph node mapping was performed by injecting iomeprole peritumorally followed by serial radiographs at 1, 3, 6 and 9-min post injection. A total of 168 SLNs were detected, 90% at first radiograph, 1 min after the peritumoral iomeprole injection, while in the rest of the cases SLN was identified at 3 min. Sentinel lymph nodes detected by the preoperative radiographic indirect lymphography with iomeprole (PRILI) differed from regional lymph nodes in 57% of cases. The PRILI technique detected simultaneously multiple SLNs in the 26% of cases and multiple lymph centers in the 31% of MCTs. To allow the surgical identification of the SLNs, a peritumoral injection of methylene blue was performed at the time of surgery. This study reports a widely available technique for SLN mapping using digital radiographs in combination with a water-soluble medium, representing a cost-effective alternative to other SLN mapping procedures. Based on our results, this technique can be effective for SLNs mapping in dogs with MCTs but further comparative studies are needed to assess its reliability and efficacy in different tumours. 相似文献