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61.
The final stages of cervical ripening and parturition resemble an inflammatory process. Although the role of cytokines in both spontaneous and experimentally induced parturitions has been described in several small laboratory animals and humans, the involvement of pro‐inflammatory and regulatory cytokines in physiologic parturition in cows has not been determined. In this study, the cytokine expression profiles were assessed in bovine cervical tissue at several stages of pregnancy and at parturition. Serial biopsy samples of the cervix were obtained from 10 cows on day 185 and day 275 of pregnancy (which was on average 5.4 days before parturition) and at parturition. Messenger RNA expression levels of interleukin (IL)‐1β, IL‐6, IL‐8, IL‐10 and tumour necrosis factor (TNF)α were determined using real‐time polymerase chain reaction and the number of neutrophils and eosinophils was estimated by Luna and Sirius Red staining. At parturition, IL‐8 expression had increased 430‐fold (p < 0.001) when compared with that of the day 185 of pregnancy, large numbers of neutrophils had invaded the cervix while eosinophils remained scarce, IL‐1β had increased eightfold (p < 0.05) and IL‐6 had not changed significantly. Additionally, IL‐10 was increased by 10‐fold (p < 0.001) and TNFα decreased by 57% (p < 0.05) when compared with that of the day 185 of pregnancy. The large increase in expression of IL‐8, enabling the influx of neutrophils, is indicative of its important role in the final stage of cervical ripening and at parturition. As previous studies have shown that neutrophils excrete matrix metalloproteinases (MMP), this might contribute to softening of the cervix. In contrast, the only slightly increased levels of IL‐1, steady concentrations of IL‐6 and decreased TNFα, the potential consequences of increased IL‐10 expression, indicate that final cervical of cows in ripening at term parturition is an inflammatory process influenced by regulatory cytokines.  相似文献   
62.
In the present study, the effect of heat stress, which is commonly observed in the animals of Upper Egypt area in summer, as well as the effect of antioxidant treatment as a thermo‐protective was examined. In this study, the animals (n = 120) were divided into winter group (n = 40, bred during winter) and summer group (n = 80, bred during summer) as well as, animals in the summer group were divided into first subgroup animals (n = 40) and injected with Viteselen intramuscularly (15 ml) twice weekly for 10 weeks and second subgroup animals (n = 40) were not treated (as control). Serum levels of progesterone (P4), oestradiol (E2), cortisol, superoxide dismutase (SOD), lipid peroxidase (LPO) and nitric oxide (NO) were measured. The pregnancy rate of all animals was detected rectally. The levels of oestradiol and the activity of the antioxidant SOD were decreased in serum of animals in behavioural oestrus during summer as compared with those in winter. During the same time period the levels of oxidants such as LPO and NO were increased in the serum of animals again in the phase of oestrus. In another group of animals treated by intramuscular injection with 15 ml viteselen (antioxidant) twice weekly for 6 weeks during hot months, the activities of serum SOD showed an increase and the levels of oxidants and cortisol decreased. Moreover, the levels of oestradiol were increased during the oestrous behaviour. The pregnancy rate was decreased in animals under heat stress and the pregnancy rate was enhanced dramatically when these animals received antioxidants during the heat stress. This means that the heat‐stress in Upper Egypt may affect the fertility of animals and pregnancy rate and this effect may be through an increased production of free radicals and decreased production of antioxidants as well as increased levels of cortisol. Treatment of animals or supplementation with antioxidants before the beginning of months of heat‐stress and also during the stress period may correct the infertility due to heat‐stress through the decrease in cortisol secretion and a decrease in the oxidative stress. These results resulted in an increase in pregnancy rate in treated animals.  相似文献   
63.
This review describes the indications for surgical treatment of distal interphalangeal joint (DIJ) infection in cattle and presents an overview of former surgical methods that have been modified for current use, including arthrotomy, resection of the distal sesamoid bone, resection of the DIJ and digital amputation. The post-operative life span, reasons for culling, pros and cons of claw-preserving techniques versus digital amputation, and pain management in general are also discussed. It would appear that severe claw diseases that result in septic arthritis of the DIJ do not necessarily lead to a reduced life span if cows are adequately treated and thorough aftercare is provided.  相似文献   
64.
日本血吸虫非叉型尾蚴感染动物试验   总被引:1,自引:1,他引:1  
试验采集云南巍山地区自然条件下的钉螺,压碎钉螺、检获尾蚴,发现为非叉型尾蚴。将非叉型尾蚴400~850条/只经皮肤感染家兔,同时,用云南洱源的叉型尾蚴作对照试验。感染后50~55 d解剖兔子,试验组检获到日本血吸虫,荷虫量为10~15条/只。试验结果表明,云南巍山非叉型尾蚴能感染动物,该试验结果为丰富日本血吸虫的生活史提供了极有价值的补充。  相似文献   
65.
66.
Effects of density and period of competition by Solanum nigrum L. on direct seeded tomatoes in relation to weed control The effects of density and period of competition from Solanum nigrum L. were measured in direct seeded tomatoes given weed control treatments currently used in south-east France. S. nigrum emerging after a diquat treatment at the 2–3 leaf stage of the crop and thinned to low densities (<12.8 plants ha?1) at the 5–6 leaf stage of the crop caused significant yield loss if left to compete with the crop until harvest. Yield reduction was smaller if the same weed densities were present only until the onset of flowering. The regression curves of yield on weed density differed as annual climatic variations affected sowing date and plant growth; a comparison between years was made using the relation ‘crop yield × weed biomass/crop biomass’. Significant interactions between weed density and period of competition were found with yield of both green and red fruit. For late sown crops with low densities of S. nigrum two weed control treatments at the 5–6 leaf stage and at the onset of flowering were sufficient to prevent yield loss.  相似文献   
67.
In a previous study, in goats, we showed that apart from variations in dietary calcium (Ca) and phosphorus intake, also low dietary nitrogen (N) intake altered plasma concentrations of hormones, which regulate Ca and phosphate (Pi) homeostasis. These hormonal responses in goats were in accordance with findings in monogastric animals and humans with low protein intake. In the aforementioned studies, alterations of electrolyte transport in the kidneys were also observed. However, whether renal electrolyte transport in goats is also involved in the adaptation of Ca and Pi homeostasis to low N intake remains unknown. Thus, the aim of the present study was to investigate whether in addition to the hormonal changes, as observed in our former study, renal Ca transport and renal Pi transport were also altered by low N intake in goats. Therefore, in kidney samples from the goats used in our former study, the protein expression of Ca and Pi transporters and of related regulatory proteins was examined. Furthermore, the uptake of Pi into isolated brush border membrane vesicles (BBMV) was detected. The results showed that the protein amount of the renal sodium‐dependent Pi transporter NaPi IIa was elevated, and concomitantly, protein expression of its upstream regulators, the parathyroid hormone receptor and the extracellular signal‐regulated kinases 1 and 2 was decreased. However, Pi uptake into renal BBMV was not enhanced. Furthermore, protein expression of the renal Ca channel, the transient receptor potential cation channel subfamily V member 5 (TRPV5) and of the vitamin D receptor was not influenced by dietary N reduction. We conclude that regulation of renal Pi transporter expression in goats is involved in the adaptation of electrolyte homeostasis to low N intake.  相似文献   
68.
One Galloway bull and three German Holstein-Friesian cows aged between three and five years with complicated arthritis of the fetlock joint were treated by arthrotomy (on the bull and two of the cows) or by arthrodesis (on the other cow). Arthrotomy involved four vertical dorsolateral/dorsomedial and palmolateral/palmomedial incisions 5 cm long to give access to the joint cavities and allow fibrin, debris and necrotic tissue to be removed. Arthrodesis consisted of lateral and medial (abaxial) horizontal 5 cm incisions along the joint space. After debridement, the joint surfaces (cartilage and superficial bone tissue) of the metacarpus and first phalanx were completely abraded with a high-speed surgical drill. The interdigital region, palmar and dorsal tendons, vessels and nerves were conserved during both arthrotomy and arthrodesis, and the pouches were flushed during the surgery. The incisions were sutured and a casting tape was applied. Six weeks later, the cast was removed and a supporting bandage was applied. Each animal received 10 mg/kg ampicillin subcutaneously twice a day from one day before surgery until a mean (sd) of 23 (4) days after the arthrotomies and 36 days after the arthrodesis. After a recovery period of at least one year, all the animals could be used without restrictions.  相似文献   
69.
Haematological and biochemical reference values were established from 45 clinically healthy koalas. Statistical analysis revealed no significant differences for sex and season of sampling. Immature koalas had significantly higher alkaline phosphatase and inorganic phosphate values, and significantly lower total protein concentrations due to low globulins values. Enzyme reference values tended to be wide and could limit their usefulness in detecting disease. In the reference values for leukocytes, neutrophils and lymphocytes, the inclusion of low values which were not actually seen may interfere with the detection of reduced levels due to disease.  相似文献   
70.
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