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71.
Pharmacokinetic variables of etomidate were determined after IV administration of etomidate (3.0 mg/kg of body weight). Blood samples were collected for 6 hours. Disposition of this carboxylated imidazole best conformed to a 2- (n = 2) and a 3- compartment (n = 4) open pharmacokinetic model. The pharmacokinetic values were calculated for the overall best-fitted model, characterized as a mixed 2- and 3-compartmental model. The first and most rapid distribution half-life was 0.05 hour and a second distribution half-life was 0.35 hour. Elimination half-life was 2.89 hours, apparent volume of distribution was 11.87 +/- 4.64 L/kg, apparent volume of distribution at steady state was 4.88 +/- 2.25 L/kg, apparent volume of the central compartment was 1.17 +/- 0.70 L/kg, and total clearance was 2.47 +/- 0.78 L/kg/h.  相似文献   
72.
The antibiograms of 408 Salmonella species isolated from large animals were collected during a three year study from 1981 through 1983. The predominant Salmonella serogroup among these isolates was group B. A consistently high percentage of all isolates were resistant to ampicillin and tetracycline. A pattern of increasing resistance to chloramphenicol and gentamicin was documented for serogroup B isolates while the susceptibility of the isolates to neomycin increased. There was a decrease in the incidence of susceptibility to sulfamethoxazole-trimethoprim among the group E isolates. These changes were not as remarkable, nor as alarming, as the overall decreased susceptibility to chloramphenicol and gentamicin. An evaluation of the principles concerning use of antimicrobial agents in veterinary medicine for treatment of Salmonella infections is recommended.  相似文献   
73.
A new, fatal mycotoxicosis of cattle has been recognised in north-western Australia. A feeding trial confirmed the toxicity of a previously unknown species of Corallocytostroma that grows on Mitchell grass (Astrebla spp). The disease has been colloquially named ‘black soil blindness’ because its most prominent features are its confinement to pastures on black soil, and blindness and death of affected animals. Over 500 cattle have died and considerable subclinical disease is present. Above average wet season rainfall and extended growing seasons may explain the emergence of the fungus. The disease is important because cattle production in large areas of Australia utilise Mitchell grass pastures.  相似文献   
74.
75.
SUMMARY Vascular leakage induced by intradermal injection of histamine, bradykinin and serotonin alone and co-injected with prostaglandin E2 was measured in Greyhounds using 125Iodine-labelled human serum albumin (125I-HSA) as a marker in the blood. Histamine and bradykinin produced dose-dependent vascular leakage. At equimolar concentrations, histamine was more than twice as potent as bradykinin. Serotonin did not induce vascular leakage and was irritant. Prostaglandin E2 did not induce significant vascular leakage (maximum 5μL) when injected alone, but when co-injected with histamine and bradykinin, the vascular leakage of both histamine and bradykinin was increased. This effect was more pronounced if lower concentrations of histamine and bradykinin were injected. The induced vascular leakage was greatest during the first five minutes of lesion development for histamine, during the second five minutes of lesion development for bradykinin, and the synergistic effect of prostaglandin E2 was maximal during the third five minute period of lesion development.  相似文献   
76.
The Southern Pine Beetle (SPB) is a major pest in southern U.S.A., Mexico, and Central America. Enormous resources in terms of funding, personnel, and effort have been allocated for research and development of pest management tools for this pest over the past century. Access to information from journal articles, reports, fact sheets, etc. does require some effort and is often incomplete and difficult to obtain. The emergence of the Internet now allows rapid access to information from diverse sources. We have created a comprehensive website entitled, 'The Southern Pine Beetle Internet Control Center' (SPBICC) (www.spbicc.vt.edu). The goal of the site is to provide all available resources on SPB to anyone with access to the Internet. It is also designed to increase communication among researchers and professionals to help advance the management of this pest. The site is interactive, which permits constant updating without contacting a webmaster. Attributes of the site include background information in the form of fact sheets, reviews, and government handbooks; an interactive diagnostic identification key for SPB and other bark beetles; a searchable expertise directory; a calendar of SPB-related events; a discussion forum; an online SPB spot growth predictive model; a searchable bibliographic database; a webcrawler designed to search for SPB-related websites, and more. Web-based tools were developed to integrate relational databases as the functional base of this site. The dynamic nature of the SPBICC makes it a powerful tool and a model for development of websites for other major agricultural or forest pests.  相似文献   
77.
A pentachlorophenol (PCP) wood treatment plant was studied to determine PCP exposure to people by occupation and to the plant by work area. This plant operates on a year-round basis with a 25 percent increase in production from May through October. Approximately 2.5 million board feet of timber are processed annually. Samples were taken in the morning of the second work week of each month for 5 consecutive months. Samples consisted of serum and urine from the employees and air from locations throughout the plant work area. All samples were analyzed for PCP residue. Peripheral blood was used to culture cells to investigate possible chromosomal aberrations.  相似文献   
78.
The proportion of weed beet and bolting beet in sugar beet crops is increasing, and as much as 24% of beet acreage may now be badly infested. Mechanical and chemical methods of control are being developed, but neither is completely satisfactory. The use of electricity has recently been suggested as a means of control and is investigated in this paper. It is found that high voltages around 5 kV rms can physically destroy annual beet in pots in under 20 sec. Maximum currents vary according to the plant size and range from 0·5 to I A rms for bolters 1-1·4 m high. It is not necessary to completely burn the plant in two to kill it and various ways of minimizing the treatment for speed and energy economy are suggested. Field trials using hand-held electrodes to apply the electric currents to annual beet growing amongst a crop showed that much larger powers (up to 20 kW) were necessary to kill the plants. A tractor-driven system was constructed producing 8kV rms which enabled it to cover 6 rows and travel at speeds up to 16 km/h and it removed 75% of the bolting and weed beet. La lutte électro-thermique contre les betteraves sauvages el les montées dans les betteraves sucrières. La proportion des ressemis et des montées dans les cultures de betteraves à sucre est en augmentation et jusqu'à 14%, des surfaces cultivées en betteraves peuvent maintenant être fortement infestées. Des procédés mécaniques et chimiques de lutte ont été proposés, mais aucun n'est pleinement satisfaisant. L'emploi de l'électricité a été récemment suggéré comme moyen de lutte el il est examiné dans cette publication. II a été constaté que des voltages élevés. autour de 5 k Veff. peuvent détruire physiquenient des betteraves de I'année. cultivées en pots, en moins de 20 sec. Les courant maximaux varient selon la talle de la plante et s'échelonnent entre 0,5 et 1 Aeff, pour des plantes montées de I m à 1,40m de haut.II n'est pas nécessaire de brûler complètement la planie pour la tuer et divers procédés économisant sur la vitesse et l'énergie sont suggérés pour alléger le traitement. Des essais du champ utilisant des électrodes manipulées à la main, pour appliquer les courants électriques aux betteraves annuelles poussant dans une culture, ont montré que des puissances élevées (jusqu'à 20 kW) étaient nécessaires pour tuer les plantes. Un dispositif tiré par un tracteur a été construit produisant 8K Veff lequel permet decouvrir 6 rangs et travaille à des vitesses atteignant 1.6 km/h; il élimine 75%, des montées et des betteraves sauvages. Elekrothermische Bekämpfung von Unkrautrüben und Zukerrübenschossern Der Anteil von Unkraut- und Schossrüben in Zuckerrüben ist ansteigend und derzeit sind 14% der Rübenfläche damit stark verseucht. Zu ihrer Bekämpfung werden mechanische und chemische Verfahren entwickelt, aber keines ist befriedigend. In dieser Arbeit wird über Untersuchungen zur neuerdings vorgeschlagenen Anwendung von Elektrizität berichtet. Unter hohen Spannungen von durchschnittlich 5 kV werden annuelle Rüben, die zu diesem Zweck in Gefässen kultiviert wurden, in weniger als 20 Sekunden zerstört. Die maximalen Stromstärken bewegen sich hierbei. Abhängig von der Pflanzengrösse, zwischen durchschnittlich 0.5 bis I A. wenn die Schossrüben 1 bis 1,4 m hoch sind. Um die Pflanze abzutöten ist es nicht nötig, sie völlig zu verbrennen. Es werden verschiedene Vorschläge zur Reduktion des Aufwandes bezüglich Fahrgeschwindigkeit und Energie gemacht. In Feldversuchen, in denen mit manuell bedienten Elektroden annuelle Rüben in einer Kultur behandelt wurden, zeigte sich, dass weit höhere Leistungen (bis zu 20 kW) notwendig waren, um die Pflanzen zu töten. Es wurde ein traktorbetriebenes Gerät konstruiert. das durchschnittlich 8 kV produziert und mit dem 6 Reihen mit einer Fahrgeschwindigkeit bis zu 1.6 km/Stunde bebandelt werden können. Mit diesem Gerät konnten 75%, der Schossrüben und Unkrautrüben beseitigt warden.  相似文献   
79.
This study aimed to evaluate the effect of oestrous synchrony between donors and recipients and the embryo quality on the pregnancy rate in beef cow recipients. The experiment was performed over two years at an embryo transfer (ET ) centre in Southern Brazil. Ninety Aberdeen Angus cows were subjected to superovulation (SOV ) protocols, resulting in the recovery of 1,048 transferable embryos. Eleven groups were formed with intervals of 6 hr, from ?30 to +30 hr, with respect to recipient versus donor oestrous detection. Evaluation of embryo quality was according to the IETS guidelines. The overall pregnancy rate was 52%. Effects related to donor and recipient oestrous synchronization on pregnancy rate were observed (=  .01), ranging from 36% to 50%. The embryo quality rate affected the pregnancy rate, where Grade I resulted in 57% and Grade III in 43% of pregnancy (<  .001). The embryonic state (frozen or fresh) showed no (>  .05) effect on pregnancy rate: 53% for fresh embryos and 44% for frozen embryos. The odds ratio for explanatory variables causing pregnancy indicated that Grade III embryos had 31% less chance of conception compared to Grade I. Thus, oestrous synchrony between donor and recipient, considering ±30 hr apart, can affect the pregnancy rate along with embryo quality.  相似文献   
80.
OBJECTIVE: To evaluate the occurrence of dorsal displacement of the soft palate (DDSP) during high-speed treadmill (HSTM) exercise in racehorses, and determine treatment efficacy relative to the endoscopic findings observed during resting and HSTM endoscopic examination. STUDY DESIGN: Retrospective study. Animals-Ninety-two racehorses (74 Thoroughbreds, 18 Standardbreds). METHODS: The signalment, history (clinical and race), treatments, and video recordings made during resting and HSTM endoscopy were reviewed in 92 racehorses that developed DDSP during HSTM exercise. Only horses that completed 3 starts before and after HSTM examination were included in performance-outcome analysis. Statistical associations were made between the independent variables (the historical findings and the resting and HSTM endoscopic findings) and performance outcome. RESULTS: Forty-five horses (49%) displaced their palate in an uncomplicated manner, whereas the other horses either had another upper-respiratory abnormality in association with DDSP (35) or displaced after swallowing (12). Although respiratory noise was not recorded during HSTM exercise, only 57 horses (62%) that developed DDSP during HSTM examination had a history of abnormal upper-respiratory noise. For the 45 horses that met the criteria for performance outcome analysis, there were no independent variables recorded during resting or HSTM endoscopy that had a significant association with performance outcome. Treatment for DDSP varied by clinician. Overall, 29 horses (64%) had improved average earnings per start after diagnosis and treatment. CONCLUSIONS: Thirty-five horses (38%) that had DDSP during HSTM endoscopy had no previous history of abnormal upper-respiratory noise, and 74 (80%) had no structural abnormalities noted on resting endoscopic examination. CLINICAL RELEVANCE: HSTM examination is an excellent tool for diagnosis of DDSP and the manner in which it occurs. DDSP did not occur similarly in all horses, and was often associated with another upper-respiratory abnormality. Thus, it is unlikely that a single treatment can be applied effectively for all horses that experience DDSP. Both surgical and medical treatments can be beneficial in improving a horse's performance after a diagnosis of DDSP is made. Neither resting nor HSTM endoscopic findings were clearly prognostic.  相似文献   
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