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301.
Comparative acute toxicity studies of the latex and sequential extracts of Leptadenia pyrotechnica (Forsk.) Decne (Asclepiadaceae) were recorded using brine shrimp. The higher toxicities were exhibited in latex; methanol, methanol/dichloromethane (1:1), defatted methanol/dichloromethane (1:1), defatted methanol and dichloromethane extracts. The other extracts; aqueous, alkaloids, ethyl acetate and n-butanol exhibited less toxicities compared with the other extracts. The estimated LC50 and its 95% confidence limits for these extracts expressed in ppm were: methanol, latex 18.84 (11.22-31.61), methanol/dichloromethane 19.95 (7.76-53.70), defatted methanol/dichloromethane 21.38 (7.24-63.10), defatted methanol 28.19 (16.27-48.81) and dichloromethane 30.90 (11.75-79.43). The anti-tumor activities; potato disc assays of methanol, ethyl acetate and alkaloids extracts showed good activities as anti-tumor agent which represented-49.30,-43.20 an -33.60%, respectively. While latex and aqueous extract represented-30.80 and-28.17%, respectively. 相似文献
302.
H. A. Saleh G. A. El-Aziz M. M. El-Fark M. El-Gohary 《Anatomia, histologia, embryologia》2009,38(5):392-399
Lead exposure during intrauterine life was found to result in reduced birth weight, impaired skeletal development and post‐natal neurotoxic effects. In this study, the effect of pre‐natal exposure to different doses of lead on the development of craniofacial skeleton in rat fetuses was investigated. Vitamin E was tested as a concomitant treatment, aiming to improve the fetotoxic effects of lead. Positively pregnant female rats were randomly divided into four groups; groups I and II (L250 and L500), exposed to lead acetate in doses of 250 and 500 mg/l respectively, group III (L500 + E), exposed to lead acetate (500 mg/l) wit concomitant vitamin E and group IV (Control) which was given sodium acetate only. All the treatments started from the first day of gestation till the 20th day, where all rats were sacrificed and the fetuses were recovered. Fetuses were processed to alizarin red staining for ossified components. Twenty‐seven bones of the craniofacial skeleton were studied in each fetus where the ossification was scored as being complete, delayed or absent. In all studied fetuses from all groups, changes were found only in eight bones while the remaining craniofacial bones were normally ossified. In affected bones there was a significant decrease in the number of completely ossified bones; associated with a significant increase of both partially ossified and absent bones in L250 and L500 treated groups when compared to the control group. These differences were more significant in the L500 treated group. Giving vitamin E improved the percentage of completely ossified craniofacial bones and decreased the percentage of both partially ossified and absent bones. The most affected bone was presphenoid, then to a lesser extent supraoccipital, squamosal, parietal, interparietal and frontal bone respectively. In conclusion, lead exposure to rats during pregnancy led to varying degrees of fetal growth retardation as well as delayed ossification of some craniofacial bones which were dose dependent and the concomitant supplementation with vitamin E greatly improved the deleterious effect of lead. 相似文献
303.
The most commercially important mollusk species from the Bulgarian Black Sea is the black mussel (Mytilus galloprovincialis). There is limited information about fat soluble vitamins, cholesterol, and fatty acid content of the Bulgarian Black Sea mussel. The aims of the present study are to determine and compare the fat soluble vitamin contents as well as relative daily intake of vitamins, cholesterol, fatty acid content, and lipid quality indices (atherogenic, thrombogenic) in the wild and farmed black mussels. Fat soluble vitamins and cholesterol were analyzed simultaneously using reverse phase high performance liquid chromatography. The fatty acid composition was analyzed by gas chromatography-mass spectrometry. In both mussels, fat soluble vitamins A and E were in high amounts, but they were a better source of vitamin D3. Cholesterol contents were 67.54 ± 0.50 mg/100 g ww (wild) and 49.88 ± 0.30 mg/100 g ww (farmed). The fatty acid distributions of wild and farmed mussels are: saturated > polyunsaturated > monounsaturated fatty acid. The n3/n6 and polyunsaturated/saturated fatty acid ratios were greater than that recommended by the Food and Agriculture Organization of the United Nations/World Health Organization (FAO/WHO). A 100-g edible portion of both mussels contained from 0.252 g (wild) to 0.425 g (farmed) of eicosapentaenoic acid (EPA, C20:5n-3) + docosahexaenoic acid (DHA, 22:6n-3). 相似文献
304.
Songqian Huang Xiaojuan Cao Weimin Wang Mona Nasr 《Fish physiology and biochemistry》2018,44(1):13-20
Artificial and natural hybridization of dojo loach Misgurnus anguillicaudatus (2N = 50, DD for short) and large-scale loach Paramisgurnus dabryanus (2N = 48, PP for short) are well-grown. However, these hybrid loaches have not yet been examined for fertility and ploidy of gametes. Here, histological observations, artificial propagation, observations of embryonic development, larval morphology, and ploidy analyses were conducted to determine the fertility and ploidy of gametes of allodiploid (DP for short) and allotriploid (DDP for short) loaches, produced by DD females × PP males and induced from fertilized eggs of DD females × PP males by cold shock to prevent the second polar body release, respectively. The ovaries of DP and DDP included smaller number of eggs when compared with those of the control DD, while full-grown oocytes were observed. Testes of these two loaches were delayed-developed without spermatids or mature spermatozoa. Results obtained here showed that DP and DDP were fertility-weakened female and sterile male. Moreover, DP females and DDP females could, respectively, produce few viable haploid eggs and few viable haploid and diploid eggs. This study will provide valuable information for fish hybrid researches. 相似文献
305.
Pedersen ME Takle H Ytteborg E Veiseth-Kent E Enersen G Færgestad E Baeverfjord G Hannesson KO 《Fish physiology and biochemistry》2011,37(4):821-831
We have previously characterized the development of vertebral fusions induced by elevated water temperature in Atlantic salmon.
Molecular markers of bone and cartilage development together with histology were used to understand the complex pathology
and mechanism in the development of this spinal malformation. In this study, we wanted to use proteomics, a non-hypothetical
approach to screen for possible new markers involved in the fusion process. Proteins extracted from non-deformed and fused
vertebrae of Atlantic salmon were therefore compared by two-dimensional electrophoresis (2DE) and MALDI-TOF analysis. Data
analysis of protein spots in the 2DE gels demonstrated matrilin-1, also named cartilage matrix protein, to be the most highly
up-regulated protein in fused compared with non-deformed vertebrae. Furthermore, real-time PCR analysis showed strong up-regulation
of matrilin-1 mRNA in fused vertebrae. Immunohistochemistry demonstrated induced matrilin-1 expression in trans-differentiating
cells undergoing a metaplastic shift toward chondrocytes in fusing vertebrae, whereas abundant expression was demonstrated
in cartilaginous tissue and chordocytes of both non-deformed and fused vertebrae. These results identifies matrilin-1 as a
new interesting candidate in the fusion process, and ratify the use of proteomic as a valuable technique to screen for markers
involved in vertebral pathogenesis. 相似文献
306.
Yui HIROSE Mona UCHIDA Masaya TSUBOI Takayuki NAKAGAWA Leo YAGA Shingo MAEDA Yasuyuki MOMOI Yugo KURIKI Mako KAMIYA Yasuteru URANO Tomohiro YONEZAWA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(4):593
Since gamma-glutamyl transpeptidase (GGT) is highly and locally expressed in human breast cancer, a GGT-enzymatically activatable fluorescent probe, gamma-glutamyl hydroxymethyl rhodamine green (gGlu-HMRG), has been developed to detect the human breast cancer area with high performance. In this study, GGT expression and the efficacy of gGlu-HMRG on visualization were investigated in canine mammary gland tumors (MGT). Seventeen non-fixed fresh-frozen MGT specimens and each peritumoral control tissue were utilized. The GGT mRNA levels were highly observed in the tumor specimens compared with the control. GGT immunostaining was mostly observed on the cell membrane and cytosol of the alveolar and duct mammary epithelium of MGT tissues. These signals were strongly positive in several cases while they were mild to not observed in other cases. When gGlu-HMRG solution was dropped to the non-fixed tissue pieces of MGT or control tissues, the fluorescence intensities (FIs) were measured using Maestro in-vivo imaging device. FIs in MGT tissues were significantly higher than each control tissue 20 min after treatment. Based on Youden index method said that the maximum sensitivity and specificity of FI was 82.4% and 82.4%. These findings suggest that GGT is highly expressed in several MGTs in dogs and gGlu-HMRG could visualize at least a part of MGT tissues in dogs. Nevertheless, it should be needed to assess the false-negative areas more carefully in canine than human cases. 相似文献