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71.
72.
Cantharidin toxicosis in horses has become an increasing problem in certain regions of the United States. Toxicosis occurs when horses ingest alfalfa hay or products that are contaminated with "blister" beetles. Clinical signs may vary from depression to severe shock and death, depending upon the amount of toxin ingested. The most frequently observed signs include varying degrees of abdominal pain, anorexia, depression, and signs suggestive of oral irritation. Many horses make frequent attempts to void urine. Less commonly observed signs include synchronous diaphragmatic flutter and erosions of the oral mucosal surfaces. Clinical laboratory abnormalities suggestive of cantharidin toxicosis include persistent hypocalcemia and hypomagnesemia, development of hypoproteinemia, microscopic hematuria, and mild azotemia with inappropriate urine specific gravity. Chemical analysis for cantharidin is accomplished by evaluation of urine or stomach contents. Treatment of cantharidin toxicosis is symptomatic, but must include removal of toxin source. Gastrointestinal protectants, laxative, intravenous fluids, analgesics, diuretics, calcium gluconate, and magnesium are all included in the treatment regimen. Early and vigorous therapy is imperative if it is to be successful. In horses that remain alive for several days, persistence of elevated heart and respiratory rates and increasing serum creatine kinase concentration are associated with a deteriorating condition. Prevention is aimed at timely harvesting of alfalfa hay. Hay fields should be inspected for the presence of beetle clusters before harvesting. Involved areas of the field should not be harvested.  相似文献   
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Abstract – The possibility to increase the proportion of migrating hatchery‐reared smolts by reducing their food ration was studied. Lake‐migrating, hatchery‐reared salmon (Salmo salar) and trout (Salmo trutta) smolts were either fed normal rations, based on recommendations from the fish‐farming industry, or reduced (15–20%) rations. They were released into the River Klarälven, western Sweden, and followed as they swam downstream to Lake Vänern, a distance of around 25 km. For both Atlantic salmon and brown trout, smolts fed a reduced ration migrated faster than fish fed a normal ration. Furthermore, a higher proportion of salmon smolts fed reduced rations migrated to the lake than fish fed normal rations in 2007 but not in 2006. This difference between years corresponded to greater treatment differences in size and smolt status in 2007 than in 2006. For trout, the proportion of migrating individuals and smolt development did not differ with ration size. Trout migrants fed a normal ration had a higher standard metabolic rate (SMR) than nonmigrants, whereas there was no difference in SMR between migrating and nonmigrating salmon. These results show that it is possible to use a reduced food ration to increase the migration speed of both Atlantic salmon and brown trout and to increase the proportion of migrating Atlantic salmon.  相似文献   
75.
A correlation betweenAlphitobius diaperinus generations and the rhythm of breeding the broilers and cleaning the poultry houses has been found. In the litter lots ofA. diaperinus larval instars can be observed. Approximately 13 days before the breeding of the broilers is completed the larvae start to leave the litter and search for hiding places for pupation in the walls of the buildings. The insects stay in these hiding places until the cleaning of the houses is finished. When the houses are prepared with new litter and higher temperatures for rearing the chickens are maintained, the beetles and larval instars leave the hiding places and continue their development, respectively laying eggs in the new litter. To prevent the insect emigration from the litter into the hiding places in the walls by temperature barriers the reactions of the adults and larvae to high temperature were tested. The results show that temperature barriers with more than 45°C only exceptionally can be overpassed by beetles and larvae.  相似文献   
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It was suggested that the cryodamage to oocytes' DNA has been responsible for the compromised developmental competence of cryopreserved oocytes. Vitrification of bovine oocytes affected not only cellular components, but also nuclear material. A significant rate of DNA fragmentation was found in bovine frozen or vitrified oocytes analysed by Comet assay regardless of cryopreservation method. Our method of vitrification using droplet system after gentle pre-equilibration treatment is one of the most effective cryopreservation methods employed for bovine oocytes so far, making it possible to develop 30% blastocyst stage embryos. In this study, the extent of DNA damage in bovine oocytes vitrified using three vitrification methods (droplet system, Open Pulled Straw and traditional vitrification in 0.25 ml insemination straws) was compared using Comet assay. Vitrification in droplet system and Open Pull Straws vitrification did not result in detectable cryoinjuries of DNA of bovine oocytes. On the contrary, DNA fragmentation was found in four of 26 oocytes vitrified in 0.25 ml straws (15.4%, p   ≤ 0.05 in comparison with the other vitrification methods).  相似文献   
78.
There are limited data concerning blood gas parameters in neonatal dogs. Knowledge of the normal physiology may facilitate effective therapeutic intervention and potentially reduce neonatal mortality. This study examined acid–base parameters in pups born at normal parturition (n = 27) compared with those born after obstetrical assistance or caesarean operation (n = 13) and those born following oxytocin (OXY) administration for treatment of uterine inertia (n = 11). Pups were subjected to an objective scoring method of neonatal health adapted from use in humans (the Apgar score) at birth and again at 5 and 60 min after birth. Venous blood samples were collected at 5 and 60 min after birth for evaluation of blood gas parameters. At birth, all pups had low Apgar scores and a mixed acidosis. The base excess was lowest for pups delivered after OXY administration. The Apgar score improved for all pups after 5 min of birth and there was an improvement in carbon dioxide tension, base excess and venous blood pH at 1 h, although in all pups a metabolic acidosis persisted. These data provide an important insight into neonatal physiology and the variability of blood gas parameters in pups born at normal and abnormal parturition and provide the basis for clinical decision making following dystocia.  相似文献   
79.
An 8-year-old terrier cross and a 10-year-old German Shorthaired Pointer presented to the University Veterinary Centre, Sydney, for investigation of long-standing tenesmus and dyschezia. Both patients had an annular adenocarcinoma at the colorectal junction. Exploratory laparotomy was performed and the affected large intestinal segment was removed by resection and anastomosis. In both dogs, the caudal mesenteric artery was intimately associated with the mass, necessitating its ligation and transection. Postoperatively, there was no evidence of anastomosis breakdown in either case and both animals recovered well from surgery. The dogs were euthanased 8 and 10 months, respectively, after surgery because of clinical signs relating to metastatic disease.  相似文献   
80.
During the last years there was a lot of progress to be seen in the development of standardized methods for microbiological ring trials. The statistical analyzing strategies, in particular the calculation of estimations for the parameters repeatability and reproducibility, will be considered in this paper. Apart from the conservative method of the variance analysis robust methods are increasingly discussed. We will compare and discuss these methods using data of recently realized ring trials. If we can assume a normal distribution of our data, then all estimations are theoretically precise and efficient. But up to now, we know very little about the character of the robust estimations, if the normal distribution cannot be assumed. In addition to this, we have to mention once more, that the use of robust estimators is unreasonable without taking a critical look on the data themselves. Thus, we will show the possibilities of graphical presentation of all data to identify laboratories with critical results.  相似文献   
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