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131.
The effects of different proportions of the 17β‐estradiol and 17α‐methyltestosterone on growth,sex reversal and skin colouration of the electric blue hap (Sciaenochromis ahli Trewavas, 1935)
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This study was performed to investigate the effects of 17β‐estradiol (ES) and 17α‐methyltestosterone (MT) on growth, development, survival, sex ratio and colour change in the electric blue hap (Sciaenochromis ahli Trewavas, 1935). The hormones were not supplemented to the control feed, while six other feeds were prepared by adding 20, 40 and 60 mg kg?1 17β‐ES or 20, 40 and 60 mg kg?1 17α‐MT to each, resulting in seven different feed treatments. Average live weight of the fish supplemented with these diets was 0.42 ± 0.04 g. At the end of the study, the highest weight gain was observed in fish fed 60 mg kg?1 17α‐MT group (2.62 ± 0.11 g) and the difference with the groups fed with 17β‐ES was found to be significant. All fish fed 17α‐MT were male, while the rates of feminization in fish fed 17β‐ES at 20, 40, 60 mg kg?1 were 91.11%, 88.88% and 93.33% respectively. Survival rates were respectively determined as 80%, 95.56%, 84.44%, 93.33%, 77.78%, 84.44% and 84.44% for the control, 20, 40, 60 mg kg?1 17β‐ES and 20, 40, 60 mg kg?1 17α‐MT treatments. The best colouration was achieved in the 17α‐MT groups (P < 0.05). The L* values varied between 32.98 ± 4.44 and 61.35 ± 2.19, a* values between ?7.06 ± 0.22 and ?3.42 ± 0.11, and b* values between ?7.74 ± 0.10 and 11.65 ± 0.03, while Chroma (C*) and Hue (H°ab) angle values varied between 7.54 ± 0.22 and 13.60 ± 0.01 and between 119.76 ± 0.05 and 239.73 ± 4.86. In conclusion, the 17α‐MT feeding was found to have a greater effect on the growth, feed conversion ratio, masculunization and pigmentation of the electric blue haps than the 17β‐ES treatment. 相似文献
132.
Many seeds of woody plants require low temperature for germination and that’s called seed dormancy has been investigated for relations of proteins by several researchers. We determined polypeptide profiles of cold-stratified Mazzard seeds. Seeds were studied in five different periods: seeds in dormancy (none stratified), 30, 60, 90 and 120 days cold-stratified. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS-PAGE) of the soluble protein fractions from stratified and none stratified seeds was utilized for determination of changes in polypeptides. SDS-PAGE revealed a decrease in the concentrations of 14 polypeptides and appearance of four low-molecular weight (15.1, 16.3, 17.8 and 19.4?kDa) polypeptides were determined in 90 and 120 day stratified seeds. The study results exhibited the evidences of the involvement of protein changes in response of Mazzard seeds during cold stratification. 相似文献
133.
The anatomical features of the autonomous nerves, including the greater, lesser and least splanchnic nerves, were examined
in 4 female and 4 male adult pigs (Sus scrofa). The origin and course of these nerves were examined with regard to sex and the side of the body. The greater splanchnic
nerve was present in all of the animals included in the study, whereas the lesser splanchnic nerve was present at a rate of
87.5% on the right side and 75% on the left side of the median plane. On the other hand, the least splanchnic nerve was present
on the right side at a rate of 62.5% and on the left side at a rate of 37.5%. The greater, lesser and least splanchnic nerves
on the right side of the median plane were determined to originate from a more cranial location. Furthermore, these nerves
were observed to be longer and larger on the right side in comparison with the left side. Evaluation of the findings revealed
no significant difference between both sides of the median plane with regard to the origin, course and dimensions of these
nerves. Similarly, no significant difference was detected between sexes. 相似文献
134.
In this study, the effect of temperature on survival and sex ratios of guppy Poecilia reticulata (Peters 1860) was investigated. Treatments of 19, 21 and 22.5°C low and 29, 32 and 35°C high water temperature were used on fry and gravid females for 11 days after parturitions and several days starting from the 16th day after first parturition until second parturition respectively. The high water temperature treatments caused the death of gravid females. Survival rates of heat‐treated fry were generally decreased with increasing and decreasing temperature. The sex ratios of the progenies from survived gravid females were not differed from a balanced sex ratio (P>0.05). The proportion of females increased gradually with decreasing temperature and the proportion of males increased gradually with increasing temperatures rather than having a threshold response in heat‐treated fry. However, mortality of heat‐treated fry was high; it is most likely that our results were biased by sex‐dependent mortality, which were also revealed by corrected sex ratios of the treatment groups and progeny testing of some individuals. These results suggest that a major gene linked to X‐chromosome could be responsible for resistance and sensitivity to both high and low temperature. 相似文献
135.
The aim of this study was to examine the histomorphometric and histochemical structure of oesophagus of the wild-caught greater mouse-eared bat M. myotis. For this purpose, 10 specimens of oesophagus were collected and processed. The oesophagus wall of M. myotis is composed of four layers: tunica mucosa, tunica submucosa, tunica muscularis and tunica adventitia. The mucosa is covered by a non-keratinized stratified squamous epithelium. There were no glands in the wall of the oesophagus. Tunica muscularis is composed of two muscle layers: internal circular muscular layer and an external longitudinal muscular layer. Histochemical studies revealed that the oesophagus was AB/PAS and PAS positive indicating the presence of acidic and neutral mucosubstances. AB-PAS staining shows that glycoproteins were predominant in the all examined layers of the oesophagus. Because of the absence of oesophageal glands in M. myotis, positive reaction with AB-PAS staining may be due to secretion of salivary glands. Absence of oesophageal glands reflects the functional adaptation as high food passage rate for the insectivorous feeding habits of animals. 相似文献
136.
137.
Tropical Animal Health and Production - Bovine spongiform encephalopathy (BSE) of the cattle is the outstanding disease among other transmissible spongiform encephalopathy (TSEs). It can be... 相似文献