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161.
天然生长促进剂之所以能促进动物的生长,主要是因为它们能够促进肠道有益菌的生长,这样就能够保护宿主动物免受病原菌的侵害,并能缓解动物遭受的应激。  相似文献   
162.
Temporomandibular joint dysplasia has been reported in several breeds of dog. Three Cavalier King Charles Spaniel (CKCS) skulls were examined and radiographed during the course of a separate study and all demonstrated changes consistent with bilateral temporomandibular joint dysplasia. Subsequently, skull radiographs from all CKCS dogs examined at the University of Glasgow Veterinary School between 1991 and 2001 were reviewed (n = 26). Only two of these dogs were radiographed specifically for investigation of the temporomandibular joint, although varying degrees of dysplasia were identified in all dogs where the joints were adequately visualized (n = 20). The head of four CKCS cadavers was also radiographed, and similar changes were found. This finding suggests that temporomandibular joint dysplasia is a widespread asymptomatic condition in the CKCS and should be regarded as a normal morphologic variation rather than a pathologic anomaly. Subtle changes are best seen on lateral oblique radiographs, although marked changes are also visible on dorsoventral views. The rotational angle or angle of articulation of each of the dysplastic mandibular condyles was measured and was related to the severity of the dysplastic changes. However, there was overlap between the values calculated for these abnormal joints and normal ones in other breeds, suggesting this measurement was of limited significance and the shape of the components of the temporomandibular joint are more relevant when assessing this joint for the presence of dysplastic changes.  相似文献   
163.
In 28 replacement pullet flocks with flock size of 4,000 to 25,000 birds Toltrazuril (experimental preparation, 2.5% solution, approx. 7 mg/kg body weight) was administered for a period of two days in the drinking water for metaphylactic purpose and therapeutic use, respectively. All flocks were reared without anticoccidial feed additives. Exposition to Eimeria spp. was recorded by examination of faecal samples and intestinal scrapings. Clinical flock control was achieved by vets at eight to ten day intervals. Toltrazuril was characterized by short application period, rapid mode of action, significant reduction of oocyst shedding, good compatibility and acceptance thus proving superior to conventional chemotherapy of coccidiosis. The results suggest that, even without administration of anticoccidial feed additives. Toltrazuril is an effective agent for therapeutic use in acute coccidiosis. Under insufficient management and rearing conditions repeated metaphylactic application has to be considered.  相似文献   
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OBJECTIVE : To determine the feasibility of indirect suture passage around the right portal vein for attenuation of right-sided intrahepatic portosystemic shunts (IHPSS). STUDY DESIGN : Anatomic study of cadavers and prospective evaluation of clinical cases. ANIMALS : Nine canine cadavers (median weight, 20.5 kg) and 6 client-owned dogs suspected of having right-sided IHPSS. METHODS : Silicone casts of the caudal vena cava and pre- and intrahepatic portal veins were made in fresh canine cadavers. A suture was passed dorsal to the portal vein above and below its bifurcation and pulled laterally so that it surrounded the right portal vein. The number and size of portal and caudal vena cava branches that interfered with the suture passage were recorded. Intra- and postoperative complications were evaluated in 3 dogs with right-sided IHPSS and 3 dogs suspected of having right-sided IHPSS that had right portal vein dissection and occlusion using this technique. RESULTS : Suture passage and placement around the right portal vein were easily accomplished in all 9 specimens. A 1 mm branch from the dorsal surface of the right portal vein was included in the encircling ligature in 4 specimens. The dissection technique was used successfully in 3 dogs with right-sided IHPSS and 2 other clinical cases. The portal branch to the papillary process of the caudate lobe interfered with suture placement in 1 dog with a central IHPSS. CONCLUSIONS : Indirect suture passage for ligation of the right portal vein can be successfully performed in normal dogs and dogs with congenital portosystemic shunts. CLINICAL RELEVANCE : Hemorrhage, vascular trauma, and surgery time may be reduced using this technique for attenuation of right-sided IHPSS.  相似文献   
168.
OBJECTIVES: To compare the effects of IV doxapram on glottic size and arytenoid motion in normal dogs and in dogs with laryngeal paralysis. STUDY DESIGN: Prospective experimental and clinical trials. ANIMALS: Six healthy dogs weighing 24.5 +/- 3.9 kg and six dogs weighing 27.4 +/- 11.5 kg suspected of having laryngeal paralysis. METHODS: Dogs were pre-medicated with acepromazine and butorphanol, and a light plane of anesthesia was induced with isoflurane by mask. Videoendoscopic examination of laryngeal function was recorded before (baseline) and after IV doxapram administration. Normalized glottal gap area (NGGA) at maximal inspiration and expiration, and percentage change in height, width, area, and NGGA were calculated with measurements from digitized images of the glottal gap. RESULTS: Active arytenoid motion was present in all normal dogs at baseline. After doxapram administration, depth of respiration appeared greater, but arytenoid motion, as measured by percentage change in NGGA, and in area and width, did not significantly increase in normal dogs. No arytenoid motion was detected in dogs with laryngeal paralysis at baseline; however, rima glottidis NGGA of dogs with laryngeal paralysis was greater at inspiration and expiration than normal dogs. After doxapram administration, dogs with laryngeal paralysis developed paradoxical arytenoid motion and significant, negative percentage change in area (-61%) and NGGA (-145%) because of inward collapse of the arytenoids during inspiration. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of doxapram during laryngeal examination is useful for differentiating normal dogs from dogs with laryngeal paralysis. Dogs with laryngeal paralysis may suffer extreme glottic constriction with vigorous respirations, and may require intubation during examination.  相似文献   
169.
In three multicentered field trials run during 1995 to 1997, involving a total of 12,928 lambs, the preventive effects on blowfly strike of a ready-to-use 5 per cent dicyclanil pour-on formulation and of a ready-to-use 6 per cent cyromazine pour-on formulation were compared with untreated controls for periods of up to 22 weeks. Their efficacy was assessed by calculating the consolidated cumulative strike rate for each treatment group and the consolidated percentage reduction of flystrike achieved by the two formulations. The consolidated cumulative strike rate for all three years together reached 29.2 per cent for the untreated control lambs at week 22, 2.8 per cent for the dicyclanil-treated lambs at week 22, and 6.9 per cent for the cyromazine-treated lambs at week 20. The consolidated cumulative percentage reduction of blowfly strike remained above 89 per cent for the dicyclanil-treated lambs. For the cyromazine-treated lambs the consolidated cumulative percentage reduction of blowfly strike reached 90 per cent during weeks 9 to 10, and 80 per cent during weeks 11 to 12.  相似文献   
170.
Eighty-four mature Norway spruce (Picea abies L. Karst), silver fir (Abies alba Mill) and Scots pine (Pinus sylvestris L.) trees were winched over to determine the maximum resistive turning moment (M(a)) of the root-soil system, the root-soil plate geometry, the azimuthal orientation of root growth, and the occurrence of root rot. The calculation of M(a), based on digital image tracking of stem deflection, accounted not only for the force application and its changing geometry, but also for the weight of the overhanging tree, representing up to 42% of M(a). Root rot reduced M(a) significantly and was detected in 25% of the Norway spruce and 5% of the silver fir trees. Excluding trees with root rot, differences in M(a) between species were small and insignificant. About 75% of the variance in M(a) could be explained by one of the four variables--tree mass, stem mass, stem diameter at breast height squared times tree height, and stem diameter at breast height squared. Among the seven allometric variables assessed above ground, stem diameter at breast height best described the root-soil plate dimensions, but the correlations were weak and the differences between species were insignificant. The shape of the root-soil plate was well described by a depth-dependent taper model with an elliptical cross section. Roots displayed a preferred azimuthal orientation of growth in the axis of prevailing winds, and the direction of frequent weak winds matched the orientation of growth better than that of rare strong winds. The lack of difference in anchorage parameters among species probably reflects the similar belowground growth conditions of the mature trees.  相似文献   
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