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261.
1. The objective was to estimate heritability, genetic and phenotypic correlations for egg quality traits of Iranian native fowl at the Yazd Breeding Centre. 2. External and internal egg quality traits were measured on 1200 eggs from 794 hens of the 6th generation. A multivariate animal model with restricted maximum likelihood procedure was applied to estimate heritability, genetic and phenotypic correlations for egg quality traits using ASREML. 3. Heritability estimates for external egg quality traits ranged from 0·18 to 0·57 and for internal egg quality traits from 0·24 to 0·60. 4. For external egg quality traits, genetic correlation between egg weight and eggshell thickness (EST) was positive (0·36) and EST showed high genetic correlations with eggshell weight (0·84) and eggshell strength (0·55). This implies that heavier eggs tend to have thicker and stronger shells. 5. For internal egg quality traits, albumen height showed high positive genetic correlations with albumen weight (0·52), albumen index (0·98), yolk height (0·72) and yolk index (0·57). 6. Our results show that it is feasible to improve egg quality in Iranian fowl through selection for albumen height.  相似文献   
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263.
This study was conducted to determine the prevalence, distribution pattern, and the Sarcocystis species involved in slaughtered water buffaloes (Bubalus bubalis) in the Khuzestan, Iran by macroscopic and histological examination. The esophagus, heart, diaphragm, tongue, masseter, and thigh muscles were investigated. Esophagus and thigh muscles of only 3 of the 100 examined water buffaloes (3%) were infected with macroscopic Sarcocystis, whereas at microscopic level Sarcocystis were found in 83 of the 100 examined animals (83%). The highest prevalence rate of microscopic cysts was found in masseter muscle (57.1%) and then followed by tongue, diaphragm, esophagus, heart, and finally, thigh muscles (30.0%). There was no significant difference between males (83.6%) and females (82.0%) or between two investigated age groups (≤2 years old, 78% versus >2 years old, 88%). Based on the size of the sarcocysts, thickness of the walls and location of the cysts, Sarcocystis buffalonis as a macroscopic form and Sarcocystis levinei and Sarcocystis dubeyi as the microscopic forms were diagnosed in the examined muscles of the buffaloes of this area. Sarcocystis fusiformis was not seen in the examined organs of these buffaloes. The high prevalence rate of microscopic Sarcocystis in this region indicates that dogs have a more significant role than cats in transmission of these protozoa.  相似文献   
264.
The inclusion of antioxidants (AOXs) has been proposed in various protocols to conserve the normal physiology of spermatozoa during (cryo) preservation. The main aim of this review was to understand the necessity of AOXs inclusion in semen extenders of caprine and ovine semen samples and to decipher physico-chemical space of AOXs used in semen extenders till now. A total 27 full-text relevant articles were finally discussed here. This systematic review showed that the inclusion of AOXs may improve the success of semen cryopreservation although at least three studies could not support this finding. AOXs have been not added after assaying total antioxidant capacity of the sample of interest, and this is principal measurement bias of all papers. Furthermore, no rational dose–response curve and precise posology have been considered in comparable studies. Furthermore, new methodologies are requested to detect the oxidative status of semen specimens before AXOs fortification and new methodologies like imaging are also needed to detect various injuries of sperms during semen (cryo)preservation. Defining computational chemical and physical spaces of AOXs which used in semen (cryo)preservation would be an interdisciplinary effort to hasten deciphering epoch-making compounds. In conclusion, more in-depth analytical, toxicological and pharmacological methodologies should be pursued in supplementation or addition of AOXs during caprine and ovine semen (cryo)preservation after determining the oxidative status of semen samples.  相似文献   
265.
This study was conducted to determine the protein quality of four types ofedible mushrooms, Terfezia claveryi, Pleurotus ostreatus, Tricholoma terreum and Agaricus macrosporus that are common inJordan. Protein efficiency ratio (PER) and net protein utilization methods(NPU) were used. The four mushroom types failed to support growth asreflected by negative values for PER; –1.76 for T. claveryi; –0.23 for P. ostreatus; –0.98 for T. terreum and–0.41 for A. macrosporus. The NPU(op), NPU(st)and NdpE% for T. claveryi were 32.6, 33.9 and 3.89%,respectively. The respective values for P. ostreatus were 38.5, 40.7and 4.35%; T. terreum 29.1, 29.8 and 3.63%; and A.macrosporus 31.5, 32.9 and 3.91%. The results showed that the fourmushrooms were significantly (p 0.05) lower in protein qualitycompared with casein results (NPU(op), NPU(st) andNDpE% of 78.5, 86.4 and 7.16%, respectively.  相似文献   
266.
267.
This study was performed to investigate the effect of periparturient body condition score on the occurrence of clinical endometritis and postpartum resumption of ovarian activity in dairy cows. Eighty-seven lactating Holstein cows, fed with a total mixed ration diet, were included into the study. Body condition scoring (using a 5-point scale with quarter-point divisions) was performed by the same investigator using the visual technique every 2 weeks, from 2 weeks before until 6 weeks after calving. Palpation of the reproductive tract and ultrasonographic assessment of ovaries for detection of corpus luteum using a rectal linear probe was also performed at 2, 4, and 6 weeks after calving. Cows with clinical endometritis had significantly lower body condition score (BCS) than normal cows at all weeks pre- and postcalving, and cows that did not ovulate until 45 days after calving had a significantly lower BCS pre- and postpartum. Cows that did not ovulate until 45 days after calving also lost more BCS from 2 weeks before to 4 weeks after calving. Besides, first ovulation after calving take occurred later in cows with clinical endometritis compared to normal cows (P?<?0.05). In conclusion, low BCS is a risk factor for postpartum endometritis and delayed cyclicity in dairy cows. BCS loss from dry-off to early lactation and occurrence of clinical endometritis can significantly affect postpartum ovarian activity.  相似文献   
268.
The objective of this paper was to evaluate the global milk quality in Tunisian dairy herds. Samples of milk were analyzed for chemical, physical and hygienic parameters. Milk total solids, fat content and density were consistently correlated and one of them can be used as a chemical indicator of milk quality. The somatic cell count value of 689 × 103/mL was higher than the recommended threshold. All milk samples were positive for the major pathogen Staphylococcus aureus. These hygienic parameters were related more closely with chloride content, minerals and electrical conductivity, which allows them to be used as indicators of mammary gland infection. It was concluded that milk producers have at hand rapid and easy tools for assessing the overall quality of milk.  相似文献   
269.
Ten Phytophthora infestans isolates were analysed for maximal growth rate (μmax), sporulation capacity (K), ploidy and the ability to produce infective F1 progeny when combined in different crosses on tomato leaflets. Ploidy was determined using three different methods: simple sequence repeats (SSR, microsatellites), allele quantification at F382Y in the RNA polymerase, and flow cytometry. Eight out of 10 isolates were classified as diploid, the other two as triploid. There was no correlation between ploidy, growth rate and sporulation capacity although the latter was rather low for triploid isolates. Ten crosses were investigated in tomato leaflets (five 2n × 2n; four 2n × 3n; one 3n × 3n). Oospore production was observed in all crosses independent of parental ploidy. Germination and pathogenicity of oospores were investigated by measuring the number of infection sites (pathogenic F1 progeny) over a time period of 72 days. All crosses containing a triploid parent produced many fewer F1 isolates than 2n × 2n crosses. The generation of pathogenic F1 progeny isolates was best for 2n × 2n crosses. A total of 319 F1 offspring were produced and analysed for mating type and ploidy; a subset was tested for ploidy with all three methods. For 2n × 2n crosses, the majority of offspring were diploid, whereas in crosses containing one or two triploid parents, diploid, triploid and trisomic offspring were observed. The results suggest that less pathogenic F1 progeny isolates are produced if at least one parent is triploid.  相似文献   
270.
Journal of Plant Diseases and Protection - Nutrient elements have a significant role in plant physiology and metabolism, and the concentration of nutrients in the plant depends on plants genetic...  相似文献   
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