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131.
Purpose To determine the normal reference range for Schirmer tear test (STT) values in clinically normal llamas (Lama glama) Animals Nine captive llamas (Lama glama) (seven females and two males) were used in this study. Procedure Complete ophthalmic examinations were performed without chemical restraint. STT I values were evaluated in both eyes of all llamas using a commercial STT strip of a single lot number (Schirmer‐Tränentest®, Germany). STT II value was also measured in both eyes of seven female llamas. Results No statistically significant differences among ages or between right and left eyes were found for any of the results. The mean ± SD STT I of 18 eyes of nine llamas was 17.3 ± 1.1 mm/min (Range 15–19 mm/min). The mean ± SD STT II of 14 eyes of seven llamas was 15.4 ± 1.7 mm/min (Range 12.5–17.5 mm/min). A paired samples t‐test demonstrated that there was a significant difference between the STT I and II values (P = 0.001). Conclusion This study provides novel data for normal reference ranges of STT I and II values in healthy llamas. Results of this study may assist veterinarians in the diagnosis of ocular surface disease and syndromes affecting the tear film in these species.  相似文献   
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Tropical Animal Health and Production - Infectious bronchitis virus (IBV) is a highly infectious pathogen, which affects the respiratory tract, reproductive system, and kidney of chickens. Many...  相似文献   
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Objective  To evaluate the effect of acepromazine or xylazine on Schirmer tear test 1 results in clinically normal cats.
Animals  Sixteen healthy cross-breed cats.
Procedure  The animals were randomly divided into two groups of eight cats each. The first group was sedated with acepromazine alone (0.2 mg/kg) and the second group received only xylazine (2 mg/kg). All cats had Schirmer tear test (STT) readings taken prior to sedation and at 15 and 25 min postsedation.
Results  Sedation with acepromazine or xylazine in cats with normal pre-sedation STT 1 values caused a statistically significant decrease in mean values of tear production in both groups. In acepromazine group the mean ± SEM STT at T15 and T25 were 4.31 ± 0.98 ( P  < 0.001) and 5.18 ± 1.07 ( P  = 0.002). The post-treatment mean ± SEM values in xylazine group were 2.18 ± 0.97 ( P  < 0.001) and 2.62 ± 1.17 ( P  = 0.001) at 15 and 25 min respectively. Comparison between T15 and T25 in acepromazine group ( P  = 0.49) and xylazine group ( P  = 0.56) revealed no significant differences.
Conclusion  These observations indicate that both acepromazine or xylazine significantly reduced tear production in clinically normal cats. In cats, clinicians should measure STT values prior to utilizing acepromazine or xylazine as sedatives in order to accurately assess the results. Moreover, sterile ocular lubricant or tear replacement should be used as a corneal protectant during sedation with these drugs.  相似文献   
135.

Background

The aim of this study was to fabricate the poly caprolactone (PCL) aligned nanofiber scaffold and to evaluate the survival, adhesion, proliferation, and differentiation of rat hair follicle stem cells (HFSC) in the graft material using electrospun PCL nanofiber scaffold for tissue engineering applications.

Methods

The bulge region of rat whisker was isolated and cultured in DMEM: nutrient mixture F-12 supplemented with epidermal growth factor. The morphological and biological features of cultured bulge cells were observed by light microscopy using immunocytochemistry methods. Electrospinning was used for production of PCL nanofiber scaffolds. Scanning electron microscopy (SEM), 3-(4, 5-di-methylthiazol- 2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, and histology analysis were used to investigate the cell morphology, viability, attachment and infiltration of the HFSC on the PCL nanofiber scaffolds.

Results

The results of the MTT assay showed cell viability and cell proliferation of the HFSC on PCL nanofiber scaffolds. SEM microscopy images indicated that HFSC are attached, proliferated and spread on PCL nanofiber scaffolds. Also, immunocytochemical analysis showed cell infiltration and cell differentiation on the scaffolds.

Conclusion

The results of this study reveal that PCL nanofiber scaffolds are suitable for cell culture, proliferation, differentiation and attachment. Furthermore, HFSC are attached and proliferated on PCL nanofiber scaffolds.Key Words: Nanofiber, Electrospinning, Stem cells, Tissue engineering  相似文献   
136.
To investigate the variability of Brenneria nigrifluens, the casual agent of shallow bark canker of Persian walnut (Juglans regia L.), a collection of 24 strains isolated from five geographic regions, was analyzed by means of three marker systems, repetitive polymerase chain reaction (rep-PCR), insertion sequence (IS50)-PCR and random amplified polymorphic DNA (RAPD). Cluster analysis was performed using UPGMA. Strains were differentiated into 6 groups at about 80% similarity according to geographic regions. This is possibly due to cultivation of Persian walnut being mainly based on the ecotype and/or local seedlings that have become adapted to particular environments and so have allowed selection of different B. nigrifluens populations. The results of this study showed that the four rep-PCR primers produced 75 products of which 73.3% were polymorphic, eight RAPD primers produced 146 fragments of which 74.6% were polymorphic and IS50 produced 32 fragments of which 93.75% were polymorphic. The usefulness of each system was examined in terms of polymorphism information content (PIC) and marker index (MI). The highest MI was observed for IS50-PCR (21.11) followed by RAPD (7.85), and rep-PCR (6.92). The Mantel test identified significant correlation between the similarity coefficients calculated from them. Among the molecular markers tested, IS50-PCR appears to be a more suitable marker for fingerprinting and assessing genetic relationships among B. nigrifluens strains. This is the first study on genetic diversity of B. nigrifluens. The results can have a bearing on the choice of disease management strategies.  相似文献   
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The amino acids (AA) and fatty acids (FA) of Beluga (Huso huso) flesh at different ages were investigated as a source of AA and FA for human consumption. The analysis of Huso huso lipids (chloroform extracted) showed significant differences (p < .05) for specific FA with age. At all ages, the major saturated FA in Huso huso fillets was palmitic acid and the major unsaturated FA were oleic and docosahexanoic acid (DHA). Protein analysis indicated that the Huso huso muscle is well balanced with good levels of essential AA and appears to be a source of high quality protein (tryptophan was not measured) with methionine/cysteine as the first limiting AA. The major AA were glutamic acid, aspartic acid, and lysine. The results obtained from the present study show that Huso huso is an excellent protein and fat source when compared with other sturgeons.  相似文献   
139.
In the this study, we evaluated the effect of replacement of fish meal by a marine microalgae Spirulina platensis on growth, digestive enzyme activities, fatty acid composition and responses to ammonia and hypoxia stress in Pacific white shrimp Litopenaeus vannamei (2.6 ± 0.2 g). Experimental diets contained S. platensis at 0%, 25%, 50%, 75% and 100% replacement levels. After 8 weeks of feeding trial, growth parameters and proximate body composition were not significantly different among treatments (p > .05). Amylase and lipase activities did not show any significant differences between control group and other experimental diets (p > .05), while activities of trypsin and chymotrypsin were significantly higher in shrimp fed diet with 50% substitution of microalgae compared to control group. Fatty acid contents, particularly polyunsaturated fatty acids (PUFAs) including arachidonic acid (ARA), docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), were significantly higher in control diet compared to other experimental diets. On the contrary, the majority of fatty acids including the contents of PUFAs in the whole body of L. vannamei fed with different levels of S. platensis were significantly higher compared to those of control group. After 48‐h exposure to ammonia, survival per cent was not statistically different between all groups (p > .05), but in hypoxia challenge, the survival per cent of control group was significantly less than that of treatments fed diets contained S. platensis (p < .05). Altogether, o ur results demonstrated the effectiveness of S. platensis as a reliable protein source for substitution of fish meal in shrimp aquaculture.  相似文献   
140.
Physico-mechanical and antioxidant properties of glycerol plasticized fish gelatin films were investigated at different levels of fish protein hydrolysates (FPH) from silver carp muscle (5, 10, 15, and 20 g FPH/100 g gelatin). The films supplemented with FPH, especially at higher concentration showed significant increase in 2, 2-diphenyl-1-picrylhydrazyl (DPPH), 2, 20-azinobis-(3-ethylbenzothiazoline-6-sulfnic acid) (ABTS) radical scavenging, and ferric reducing antioxidant power (FRAP), elongation at break, difference of color, water vapor permeability and opacity, while tensile strength, elastic modulus, L*, b*, and contact angle decreased markedly (p < 0.05). However, no significant differences were observed for a* and solubility of all samples (p > 0.05). Films prepared using 20% FPH had lower glass transition temperature and more homogeneous structure, compared with control film. Also, Fourier transform infrared (FTIR) spectroscopy confirmed the increase of free groups of hydrolysates and lower interaction between chains of film incorporated with the highest content of FPH. Thus, these results indicate that FPH enhanced the antioxidant activities and affected some characteristics due to less interaction between gelatin and FPH.  相似文献   
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