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31.
In situ measurements of chlorine monoxide (ClO) at mid- and high northern latitudes are reported for the period October 1991 to February 1992. As early as mid-December and throughout the winter, significant enhancements of this ozone-destroying radical were observed within the polar vortex shortly after temperatures dropped below 195 k. Decreases in ClO observed in February were consistent with the rapid formation of chlorine nitrate (ClONO(2)) by recombination of ClO with nitrogen dioxide (NO(2)) released photochemically from nitric acid (HNO(3)). Outside the vortex, ClO abundances were higher than in previous years as a result of NOx suppression by heterogeneous reactions on sulfate aerosols enhanced by the eruption of Mount Pinatubo.  相似文献   
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SUMMARY Postprandial insulin and glucose concentrations were measured in 3 Arabian and 3 Thoroughbred foals at 1 day, 1 week, 1 month and 3 months of age. Prefeeding serum Insulin concentrations were similar in foals at 1 day (25.9 ± 5.1 pmol/L), 1 week (32.4 ± 5.8 pmol/L), and 1 month (38.2 + 7.9 pmol/L), but had Increased significantly to 131.0 ± 20.2 pmol/L at 3 months of age (P < 0.05). There was significantly increased serum Insulin secretion after a feed In foals at 3 months of age (P < 0.05) when compared with that at younger ages. Prefeeding serum glucose concentrations ranged from 6.0 ± 0.7 mmol/L at 1 day, to 5.9 ± 0.9 mmol/L at 1 week, 4.9 ± 1.7 mmol/L at 1 month, and 4.4 ± 1.5 mmol/L at 3 months of age. There were lower postprandial glucose concentrations with advancing age. It appeared that there was a period of maturation in pancreatic β-cell function after birth in foals, which reached adult levels by 3 months of age.  相似文献   
34.
Feeding unsaturated oils to lactating dairy cows impair ruminal biohydrogenation (BH) of unsaturated fatty acids (USFA) and increase ruminal outflow of BH intermediates such as trans‐10, cis‐12 CLA that are considered to be potent inhibitors of milk fat synthesis. Supplementing lactating dairy cow’s rations containing plant origin oils with monensin and/or vitamin E may minimise the formation of trans‐10 isomers in the rumen, thereby preventing milk fat depression. Therefore, this study was conducted to evaluate the effects of monensin and vitamin E supplementation in the diets of lactating dairy cows containing whole cottonseed, as the main source of FA on feed intake, milk production and composition, milk fatty acid profile, efficiency of nitrogen (N) utilisation, efficiency of net energy (NE) utilisation and nutrients digestibilities. Four multiparous Holstein lactating dairy cows (86 ± 41 days in milk) were assigned to a balanced 4 × 4 Latin square design. Each experimental period lasted 21 days with a 14 days of treatment adaptation and a 7 days of data collection. The control diet was a total mixed ration (TMR) consisted of 430 g/kg forage and 570 g/kg of a concentrate mixture on dry matter (DM) basis. Cows were randomly assigned to one of the four dietary treatments including control diet (C), control diet supplemented with 150 mg of vitamin E/kg of DM (E), control diet supplemented with 24 mg of monensin/kg of DM (M) and control diet supplemented with 150 mg of vitamin E and 24 mg of monensin/kg of DM (EM). Dry matter intake (DMI) ranged from 19.1 to 19.5 kg/d and was similar among the dietary treatments. Dietary supplementation with vitamin E or monensin had no effect on milk production, milk fat, protein and lactose concentrations, efficiency of utilisation of nitrogen and net energy for lactation (NEL). Digestibility of DM, organic matter (OM), crude protein (CP) and ether extract (EE) was not affected by the dietary treatments. Digestibility of neutral detergent fibre (NDF) was higher in cows fed with the M and EM diets in relation to those fed the C and E diets. The concentrations of C4:0, C6:0, C8:0, C10:0, C12:0, C14:0, C15:0, trans‐10‐16:1, cis‐9‐16:1, 17:0, 18:0, trans‐11‐18:1, cis‐9‐18:1, cis‐9, trans‐11 conjugated linoleic acid (CLA), trans‐10, cis‐12 CLA, and 18:3n‐3 FA in milk fat were not affected by the dietary supplementations. While feeding the M diet tended to decrease milk fat concentration of C16:0, the milk fat concentration of C18:2n‐6 FA tended to be increased. Dietary supplementation with vitamin E or monensin had no effect on milk fat concentrations of saturated, unsaturated, monounsaturated, polyunsaturated, short chain and long chain FA, but feeding the M diet numerically decreased milk fat concentration of medium chain fatty acids (MCFA). The results showed that vitamin E and/or monensin supplementations did not improve milk fat content and did not minimise the formation of trans‐10 FA isomers in the rumen when whole cottonseed was included in the diet as the main source of fatty acids.  相似文献   
35.
The objective was to examine the effects of supplementing dams with dietary melatonin during late gestation on offspring growth and cardiovascular measurements. On day 190 of gestation, heifers (n = 20) were blocked by body weight and randomly assigned to one of two dietary treatments consisting of 20 mg of dietary melatonin per day [melatonin (MEL)] or no melatonin supplementation [control (CON)]. Dietary treatments were terminated on day 262 of gestation. At birth, calves were separated from their dams with no further treatments. Calf (n = 18) blood pressure, cortisol, nitrites and total antioxidant capacity were collected on weeks 0, 1, 2, 3 and 4 of age. Calf hepatic portal blood flow and concentrations of insulin‐like growth factor 1 were determined on weeks 0 and 4 of age. Calf body weight, abdominal girth, hip height and wither height increased (p < 0.05) with age. An age by treatment interaction (p < 0.01) was observed for calf body weight, which was increased at weeks 8 and 9 of age in calves born to MEL heifers compared to calves born to CON heifers. Pulse pressure, mean arterial pressure, absolute hepatic portal blood flow and blood flow relative to calf body weight were not different (p > 0.05) between treatments. A main effect of calf age (p < 0.05) was observed for concentrations of insulin‐like growth factor 1, which was decreased at week 4 compared to week 0. An age by treatment interaction (p < 0.05) was observed for cortisol, which was decreased at week 2 in calves from MEL‐treated dams compared to calves from CON‐treated dams. Early post‐natal growth was altered in offspring born to dams supplemented with dietary melatonin. This could lead to further foetal programming implications in conjunction with post‐natal development.  相似文献   
36.
A three‐year‐old intact female Old English sheepdog was presented for evaluation of infertility. A uterine biopsy was performed during dioestrus, and the microscopic appearance was inconsistent with progesterone stimulation; the glands were sparse, simple and failed to show coiling, while the glandular epithelium was cuboidal instead of columnar. There was very little evidence of glandular activity. Due to the inappropriate appearance of the glands for the stage of the cycle, immunohistochemistry for progesterone receptors was performed. No progesterone receptor‐positive immunoreactivity was identified in the endometrial luminal epithelium, glandular epithelium or stroma. Weak intranuclear immunoreactivity was identified within the smooth muscle cells of the myometrium. The absence of progesterone receptors within the endometrial glands is the most likely explanation for the abnormal appearance of the endometrium and for this bitch's infertility. To our knowledge, this is the first report of endometrial progesterone receptor absence in a bitch.  相似文献   
37.
Although preventive epidural morphine administration with bupivacaine is effective in producing long‐lasting analgesia, neuraxial anaesthesia can cause cardiovascular depression and pruritus. This report presents the development and treatment of hypotension and pruritus after intrathecal morphine and bupivacaine administration in a 3‐year‐old female spayed Domestic Short‐hair cat presented for surgical repair of a torn right cranial cruciate ligament. Opioid‐induced pruritus is not usually considered a frequently occurring complication, but may be easily misinterpreted as being dysphoria in recovery. It can be treated by administration of ondansetron, with human patients usually responding within 30 min after treatment.  相似文献   
38.
采用石蜡切片技术对粗毛淫羊藿的大孢子形成及雌配子体发育过程进行观察。结果表明:粗毛淫羊藿子房单心皮1室,每室胚珠多数,双珠被,厚珠心,倒生胚珠。大孢子母细胞经减数分裂形成直线形排列的4个大孢子,合点端大孢子发育成功能大孢子,其余3个退化。胚囊发育类型为蓼型。  相似文献   
39.
A field study conducted for three crop years (June?–?July) from 1995?–?96 to 1997?–?98 at the Indian Agricultural Research Institute, New Delhi involving five rice-based cropping systems and six nutrient combinations indicated that rice?–?wheat?–?mungbean (RWM), rice?–?potato?–?mungbean (RPM), rice?–?rapeseed?–?mungbean (RRsM) and rice?–?clover (RC) cropping systems gave 0.7?–?1.0, 3.2?–?5.9, 0.2?–?2.2 and 1.5?–?3.6 t ha?1 yr?1, respectively, higher productivity and removed 7.9?–?22.6, 38.0?–?64.5, 53.0?–?61.8 and 51.4?–?66.1?kg ha?1 yr?1, respectively, more nitrogen, 2.3?–?7.1, 14.5?–?22.8, 3.8?–?7.2 and 17.3?–?21.7?kg ha?1 yr?1, respectively, more phosphorus and 1.6?–?11.4, 15.3?–?42.3, 8.2?–?22.7 and 40.8?–?57.8?kg ha?1 yr?1, respectively, more potassium than the rice?–?wheat (RW) cropping system which led to a net balance of +?151, +?58, ??153 and ??167?kg ha?1 of nitrogen, +?13, ??27, ??8 and ??59?kg ha?1 of phosphorus and ??549, ??551, ??558 and ??691?kg ha?1 of potassium after three cycles of RWM, RPM, RRsM and RC cropping systems, respectively against a net balance of +?201, +?26 and ??533?kg ha?1 of N, P and K, respectively in the RW cropping system. Application of FYM along with NPK in these cropping systems changed the negative balance of nitrogen and phosphorus into positive balance and reduced the negative balance of potassium by 151?–?378?kg ha?1. Application of P and K fertilizers along with nitrogen also helped in arresting the negative balance of P and K under different rice based cropping systems. These results thus indicate that balanced use of NPK and FYM plays a major role for sustaining the productivity of a cropping system.  相似文献   
40.
Twenty-one microbial preparations recommended for controlling pathogenic fungal strains causing root rot and wilt diseases of faba bean were investigated for antibiosis against several symbiotic and associative diazotrophs adopting a modified agar-plate-inhibition-zone assay. Rhizobium and Bradyrhizobium exhibited a somewhat similar susceptibility to biocontrol agents while associative diazotrophs showed variable responses. Azotobacter, compared to others, was severely inhibited by such bio-candidates. The members of the biofertilizer formulation ‘Biofertan’ did bear mixed cultivation with the majority of biocontrol agents. Among those, Bacillus subtilis was deemed the pioneer. In pot experiments, almost all the antagonists significantly restricted the severity of root rot and wilt diseases besides modifying faba bean seedling stand and improving plant development. This was very obvious with shoot biomass increases of >?50%. Moreover, the bioagents successfully recovered the legume establishment, seriously injured due to pathogenic fungal infection. Simultaneous inoculation with Rhizobium and biocontrol agents provided more growth stimulation compared to either when introduced individually. Field-grown faba beans were inoculated with the diazotroph and representatives of biocontrol strains by two different methods, seed coating and over-head soil. Growth parameters determined were the highest when the legume plant was seed-coated by Rhizobium simultaneously over-head soil inoculated with the bacterial bioagents; this was reported with Bacillus subtilis and Pseudomonas aerugenosa. The significance of combined application of biofertilizer and bioagent to ensure cheap, clean and safe farm products is discussed.  相似文献   
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