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排序方式: 共有281条查询结果,搜索用时 15 毫秒
1.
Bijan Soleymani Kamran Mansouri Mohsen Rastegari-Pouyani Shahram Parvaneh Fatemeh Khademi Mehdi Sharifi Tabar Ali Mostafaie 《Reproduction in domestic animals》2021,56(2):270-277
Separation of X and Y chromosome-bearing sperm is an appropriate method for the selection of desired sex of offspring to increase the profit in livestock industries. The purpose of this study was the production of a monoclonal antibody against recombinant bovine sex-determining region Y protein for separation Y sperm. The hybridoma cells from splenocytes of immunized female's balb/C mice and Sp2/0 cells were made. The binding affinity of our monoclonal antibody (mAbSRY2) was compared with mouse monoclonal SRY-15. The Western blot method indicated that mAbSRY2 successfully detected the rbSRY protein. The specificity and sensitivity of mAbSRY2 is comparable to SRY-15 commercially ones. The SRY gene in 100% of bull semen contains the Y chromosome that had the strongest binding affinity to mAbSRY2 was synthesized. In other words, the binding affinity of semen contains the X sperms near the negative control. In general, this immunological method can help to separate X from Y sperms. However, the mAbSRY2 is bind to Y-bearing sexed sperm, but in the future; the sexed sperms need to apply in farms. 相似文献
2.
ABSTRACTThis study was conducted as a trial of using dry whey meal (DWM) as a substitute for fish meal (FM) in practical diets for Nile tilapia, Oreochromis niloticus. Triplicate fish groups were fed on five isonitrogenous (30.2%) and isolipidic (6.9%) diets. The control diet (D1) used FM as the sole protein source. In the other four diets (D2–D5), FM protein was substituted by 25, 50, 75, or 100% DWM. Fish (3.5 ± 0.1 g) were stocked at a rate of 20 fish per 100-L aquarium and fed one of the tested diets up to satiation twice daily for 12 weeks. Fish growth, feed utilization, protein efficiency ratio, apparent protein utilization, and energy utilization for fish fed DWM diets up to 75% FM (D2–D4) tended to be higher but were not statistically different than the control diet. No significant effect of diet was found in whole-body moisture, crude protein, and total ash contents. Whole-body lipid content in fish fed the 100% DWM (D5) diet was significantly higher than that for fish fed the control diet. The optimal replacement level of FM by DWM was estimated by second-order polynomial regression to be 62.5%. 相似文献
3.
Comparative effects of Shirazi thyme and vitamin E on some growth and plasma biochemical changes in common carp (Cyprinus carpio) during cadmium exposure 下载免费PDF全文
Mohammad Mohiseni Maryam Sepidnameh Dara Bagheri Mahdi Banaee Behzad Nematdust Haghi 《Aquaculture Research》2017,48(9):4811-4821
Phytobiotics include a large number of active components which potentially have a growth‐promoting effects and antioxidant properties. This study was conducted to investigate the protective effects of Shirazi thyme and vitamin E on growth and plasma biochemical parameters of common carp exposed to cadmium. Fish (34 ± 3 g) were divided into four groups and fed four distinct diets including commercial diet without any additive (for control and metal only group) and supplemented with either 1% ground Shirazi thyme or 100 mg kg?1 vitamin E for 45 days. At the end of the feeding trial, all treatments except control group were exposed to sub‐lethal concentration of waterborne cadmium for 15 days and sampling was done on days 0, 7 and 15 after the metal exposure. According to the results, dietary inclusion of thyme prevented the harmful effects of cadmium and also improved fish growth and nutritional indices including weight gain, feed conversion ratio, specific growth rate and condition factor. Results also revealed that Shirazi thyme was more effective than vitamin E. Similarly, no changes in the hepatosomatic, viscerosomatic and bile somatic indices were observed. Plasma enzymes (AST, ALT, ALP and LDH) and metabolites were not altered due to thyme supplementation compared to the control. In conclusion, dietary supplementation of 1% ground Shiraz thyme improved the growth and health status of fish and showed better hepatorenoprotective properties than vitamin E during waterborne cadmium exposure in common carp juveniles. It might be conceivable to consider Shirazi thyme as a potential phytobiotic for incorporation in fish diet. 相似文献
4.
Free‐floating macrophytes are often common in standing water bodies. Fishponds are suitable medium for Azolla growth; however, it rapidly self‐propagates and doubles its biomass in a few days and could strongly influence nutrient dynamics. The preference of Tilapia zillii (Gervais) to consume the free‐floating plant, Azolla pinnata, was tested in two experiments. In the first experiment, fish with different initial body weights (2–3 g, 7–10 g, 15–20 g, and 50–60 g) were randomly distributed at a rate of 150 ± 5 g/100‐L aquarium and fed fresh A. pinnata for 8 wk. A known weight of fresh plant was given to fish; after 24 h, Azolla remaining in aquaria was collected, dried with tissue paper, and reweighed to determine amount consumed. In the second experiment, fish were fed one of five diets containing different levels of dry Azolla meal as replacements of the control diet (20% crude protein) at levels of 0 (control), 25, 50, 75, or 100% for 13 wk. Growth retardation and weight loss were observed in all fish sizes fed fresh Azolla, and the mortality rates were 53.3–56.7%. The consumption of fresh Azolla decreased over time up to the eighth week; otherwise, Azolla consumption was fish size dependent. Whole‐body contents of crude protein decreased significantly, while total lipids and ash contents increased significantly with increasing fish size. In the second experiment, fish growth was reduced when the level of dry Azolla meal in the diet exceeds 25%. The mortality rate increased significantly with increasing Azolla level in the diet. Carcass composition showed increases in moisture and ash contents and decreases in dry matter, crude protein, and total lipids with the increase of Azolla level in the diets. Amount of diet consumed decreased, while feed conversion ratio increased significantly with the increase in dry Azolla level in the diet. Moreover, protein efficiency ratio, protein productive value, and energy utilization decreased significantly with the increase in dry Azolla level in the diet. It could be concluded that the preference of T. zillii to consume Azolla plants inhabiting water bodies is limited, but it could partially consume the dry Azolla meal at low and moderate levels. The optimum inclusion level of dry Azolla meal should be no more than 25% in T. zillii diet. 相似文献
5.
6.
A study was conducted to investigate the effects of skid trail slope and traffic levels on soil disturbances at two soil depths
(0–10 and 10–20 cm). The treatments were set at four traffic levels (2, 7, 12 and 20), two slope classes (<20% and >20%) and
two soil depths (0–10 and 10–20 cm). Results show that skidder traffic, longitudinal slope and soil depth have significant
effect on soil bulk density in skid trail. Comparison of average soil bulk density in different traffic levels shows that
there are significant differences in average bulk density between different traffic levels and control (p<0.05). The average bulk densities in different slopes and soil depths are significantly increased with increase in traffic
levels, maximized at 12 passes (p<0.05), but there are no significant differences between 12 and 20 passes. The interaction effects between traffic and soil
depth are significant (F
0.05,3=0.109, p<0.001). For all traffic treatments, there are significant differences in soil moisture content between the two slope classes
and the two depths (p<0.001). However, the interaction effects between traffic levels and slope classes are not significant (p >0.05), although skidder traffic and slope affected soil moisture content. 相似文献
7.
Abdel-Tawwab Mohsen Eissa El-Sayed Hemdan Tawfik Wesam A. Abd Elnabi Heba E. Saadony Saadea Bazina Walaa K. Ahmed Ragaa A. 《Fish physiology and biochemistry》2022,48(3):585-601
Fish Physiology and Biochemistry - The current study investigated the effects of dietary curcumin nanoparticles (C-NPs) on the performance, hemato-biochemical profile, digestive enzymes activities,... 相似文献
8.
Morteza Pourreza Seyed Mohsen Hosseini Ali Akbar Safari Sinegani Mohammad Matinizadeh Seyed Jalil Alavai 《林业研究》2014,25(1):113-120
Zagros forests are mainly covered byQuercus brantii L. coppices and oak sprout clumps occupy the forest area like patches. We investigated post-fire herbaceous diversity in the first growing season after fire. For this purpose neighboring burned and unburned areas were selected with the same plant species and ecological conditions. The data were collected from areas subjected to different fire severities. Overall 6 treatments were considered with respect to fire severity and the mi-crosites of inside and outside of oak sprout clumps including: unburned inside and outside of sprout clumps (Ni and No), inside of sprout clumps that burned with high fire severity (H), inside of sprout clumps that burned with moderate fire severity (M), outside of sprout clumps that burned with low fire severity (OH and OM). Different herbaceous com-position was observed in the unburned inside and outside of oak sprout clumps. The species diversity and richness were increased in treatments burned with low and moderate fire severity. However, in treatment burned with high fire severity (H), herbaceous cover was reduced, even-ness was increased, and richness and diversity were not significantly changed. We concluded that besides the microsites conditions in forest, fire severity is an inseparable part of the ecological effect of fire on her-baceous composition. 相似文献
9.
10.
Mohsen Dadar Saeid Ansari Mahyari Mohammad Rokouei Mohammd Ali Edriss 《Animal Science Journal》2014,85(10):888-894
The accumulation of inbreeding and the loss of genetic diversity is a potential problem in Holstein dairy cattle. The goal of this study was to estimate inbreeding levels and other measures of genetic diversity, using pedigree information from Iranian Holstein cattle. Edited pedigree included 1 048 572 animals. The average number of discrete generation equivalents and pedigree completeness index reached 13.4 and 90%, respectively. The rate of inbreeding was 0.3% per year. Effective number of founders, founder genomes, non‐founders and ancestors of animals born between 2003 and 2011 were 503, 15.6, 16.1 and 25.7, respectively. It was proven that the unequal founder contributions as well as bottlenecks and genetic drift were important reasons for the loss of genetic diversity in the population. The top 10 ancestors with the highest marginal genetic contributions to animals born between 2003 and 2011 and with the highest contributions to inbreeding were 48.20% and 63.94%, respectively. Analyses revealed that the most important cause of genetic diversity loss was genetic drift accumulated over non‐founder generations, which occurred due to small effective population size. Therefore, it seems that managing selection and mating decisions are controlling future co‐ancestry and inbreeding, which would lead to better handling of the effective population size. 相似文献