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21.
Based on observations in laboratory animals interleukins could be regulators of testicular development. The objects of this study were to see if interleukins (IL‐1 and IL‐6) are present in the developing bull testis and to establish the temporal patterns of concentrations of IL‐1 and IL‐6 in the bovine testis during development. Separate groups of six bull calves were castrated every 4 weeks from 5 to 33 weeks of age, and at 56 weeks of age. Mean testicular IL‐1 alpha concentrations decreased (p < 0.01) from 5 to 9 weeks of age and 13 to 21 weeks of age. Mean testicular IL‐1 beta concentrations decreased (p < 0.01) from 13 to 17 weeks of age and from 29 to 33 weeks of age. Mean IL‐1 bioactivity increased from 13 to 17 weeks of age, decreased to 21 weeks, increased to 25 weeks, decreased to 29 weeks and decreased from 33 to 56 weeks of age (p < 0.05). Mean testicular IL‐6 concentrations decreased (p < 0.05) from 9 to 13 weeks of age, increased (p < 0.05) to 21 weeks, decreased (p < 0.05) to 25 weeks, increased (p < 0.05) to 29 weeks and decreased (p < 0.01) to 56 weeks of age. In conclusion, testicular IL‐1 alpha, IL‐1 beta and IL‐6 were found in the bovine testis and concentrations were age dependent. Testicular IL‐1 alpha and IL‐1 beta concentrations were highest in the early post‐natal period; however, IL‐1 bioactivity and IL‐6 concentrations were greatest in the immediate pre‐pubertal period. These findings suggest a functional role for interleukins in testicular development in the bull.  相似文献   
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Leaf‐cutting ants are generally recognized as important pest species in Neotropical America. They are eusocial insects that exhibit social organization, foraging, fungus‐cultivation, hygiene and a complex nest structure, which render their management notoriously difficult. A lack of economic thresholds and sampling plans focused on the main pest species preclude the management of leaf‐cutting ants; such management would facilitate their control and lessen insecticide overuse, particularly the use of insecticidal baits. Recent restrictions on the use of synthetic compounds for such purposes impose additional challenges for the management of leaf‐cutting ants. Considerable effort has been exerted regarding these challenges, which are addressed herein, but which also remain challenges that are yet to be conquered. © 2013 Society of Chemical Industry  相似文献   
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The aim of this study was to assess the ultrasonographic characteristics of ovulatory follicles in cyclic Western White Face ewes (December) that had received intravaginal sponges containing medroxyprogesterone acetate (MAP; 60 mg) for 12 days, with or without an injection of 500 IU of equine chorionic gonadotropin (eCG) at sponge removal. We hypothesized that quantitative echotextural attributes of the follicles in ewes treated only with MAP would differ from those in MAP/eCG-treated ewes, reflecting the increased antral follicular growth and secretory function under eCG influence. Digital images of ovulatory follicles obtained at 0 and 24 h after MAP sponge removal and at 24 h before ovulation in the eCG-treated (five ewes, 13 follicles) and control (six ewes, 9 follicles) animals, were subjected to computerized analyses. The mean diameter of ovulatory follicles increased (p < 0.001) 24 h after eCG treatment. The mean pixel intensity and heterogeneity of the follicular antrum (p < 0.001), as well as mean pixel intensity of the follicular wall and perifollicular ovarian stroma (p < 0.05), were greater in eCG-treated animals compared with control ewes 24 h after sponge removal and at 24 h before ovulation. Mean serum concentrations of oestradiol-17beta tended to increase (p = 0.06) 24 h after eCG treatment and the eCG-treated ewes exceeded (p < 0.05) control animals in progesterone concentrations from days 9-15 after ovulation. Our results support the hypothesis that large antral follicles in eCG-treated ewes exhibit distinctive echotextural characteristics. Follicular image attributes in eCG-treated ewes appear to be indicative of the changes in follicular morphology and secretory activity caused by the administration of the exogenous gonadotropin, which has both FSH- and LH-like activities.  相似文献   
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This study was undertaken to assess the effect of blended oils, i.e., polyunsaturated fatty acid (PUFA) rich vegetable oils like safflower oil (SFO) and sunflower oil (SNO) with the unconventional and hypocholesterolemic rice bran oil (RBO) on the serum lipid profile of rats. Rats fed RBO + SNO/SFO at 70:30 ratio for a period of 28 days showed significantly (p < 0.05) lower levels of total cholesterol (TC), triglycerides (TG) and low density lipoprotein (LDL) cholesterol and increased high density lipoprotein (HDL) cholesterol in animals fed a high cholesterol diet (HCD) and cholesterol free diet (CFD). Liver total cholesterol (TC) and triglycerides (TG) were also reduced. Fecal excretion of neutral sterols and bile acids was increased with use of RBO blends. RBO, which is rich in tocopherols and tocotrienols, may improve the oxidative stability of the blends. Tocotrienols are known to inhibit 3-hydroxy, 3-methyl, glutaryl CoA (HMG-COA) reductase (rate limiting enzyme in cholesterol biosynthesis), resulting in hypocholesterolemia. In addition to improving the lipid profile by lowering TC, TG and LDL-C and increasing HDL-C, blending of RBO with other oils can result in an economic advantage of lower prices.  相似文献   
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In the present study the selenium and chromium content of different plant foods such as fruits, greens, flowers, vegetables, dried fruits, spices, condiments, cereals and pulses were analysed. The selenium values for cereals indehiscent vegetables, root vegetables, stem vegetables, pulses, fleshy vegetables, greens, fleshy fruits, condiment seeds, spices and dried fruits ranged between 24.2–32.16, 2.4–18.9, 2.8–21.5, 3.0–32, 48.7–92.5, 1.25–9.5, 3.0–8.2, 2.0–9.4, 6.2–66.2, 6.2–17.5 and 3.5–16.8 g/100 g respectively. The chromium values for the same ranged between 48.2–52.6, 31.0–45, 21.2–25.7, 23.7–62.8, 15.0–43.5, 20.4–65, 14.2–42.1, 14.25–46.7, 58.4–150 and 96–168 g/100 g respectively. Thus dried fruits have the highest chromium content and pulses the highest selenium content.  相似文献   
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Lupeol, a pentacyclic triterpene and its ester derivative, lupeol linoleate, were investigated for their possible hepatoprotective effect against cadmium-induced toxicity in rats. Cadmium intoxicated rats showed elevated levels of malondialdehyde (basal and induced), and decreased levels of antioxidants and antioxidising enzymes in the liver. The oral administration of triterpenes (150 mg/kg, once a day for 3 days before injection of cadmium chloride) changed the tissue redox system by scavenging the free radicals and by improving the antioxidant status of the liver. Lupeol linoleate had a better effect on the antioxidant status of the liver, when compared to lupeol.  相似文献   
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In this paper, a new uterine discharge index (D‐index) was created and tested. It was based on a principal component analysis (PCA) of clinical findings of classical uterine discharge symptoms and rectal temperature during the postpartum period of dairy cattle. The PCA analysis revealed how uterine discharge features relate to each other and how they cluster together possibly representing different degrees of uterine inflammation. The D‐index was the result of the multivariate PCA‐analysis, and the D‐index gives a continuous value between 0 and 10. It was demonstrated that the same scale, i.e. the D‐index, can be used without any adjustment from 1 to 6 weeks post‐calving. It is valid for any type of uterine discharge without defining the type of infection or differentiating between infection and contamination. The D‐index was tested using the uterine involution data. Uterine involution was significantly delayed in the high‐D‐index group of cows. Similarly, in the test with all cows, involution was progressively delayed and the rate of involution of the pregnant horn was slowed down with the increase of the D‐index values. It is concluded that the D‐index can be a new practical, universal, tool for improved management of dairy cows in the postpartum period under commercial conditions.  相似文献   
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