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31.
Volatile compounds were isolated from Costa Rican guava fruit by simultaneous steam distillation-solvent extraction according to the Likens-Nickerson method. Compounds were identified by capillary GC-MS and sensorially characterized by sniffing-GC. One hundred and seventy-three components were identified in the aroma concentrate, from which (E)-beta-caryophyllene, alpha-terpineol, alpha-pinene, alpha-selinene, beta-selinene, delta-cadinene, 4,11-selinadiene, and alpha-copaene were found to be the major constituents. The amounts of aliphatic esters and terpenic compounds were thought to contribute to the unique flavor of this fruit.  相似文献   
32.
Volatile compounds were isolated from four cultivars of bullock's heart fruit (Cenizo, Rojo, Verde, and De Ojo) by simultaneous steam distillation-solvent extraction. Compounds were identified by HRGC and capillary GC-MS. One hundred and eighty compounds were identified in the aroma extracts, of which alpha-pinene, beta-pinene, myrcene, limonene, terpinen-4-ol, and germacrene D were found to be the major constituents. Fruit from cv. De Ojo containing the highest concentration of total volatile and the highest major terpenoid content had the highest custard-like and overall fruity aroma intensity. The presence of many terpenic compounds is thought to contribute to the unique flavor of the bullock's heart fruit.  相似文献   
33.
The volatile components of 20 mango cultivars were investigated by means of simultaneous distillation-extraction, GC, and GC-MS. Three hundred and seventy-two compounds were identified, of which 180 were found for the first time in mango fruit. The total concentration of volatiles was approximately 18-123 mg/kg of fresh fruit. Terpene hydrocarbons were the major volatiles of all cultivars, the dominant terpenes being delta-3-carene (cvs. Haden, Manga amarilla, Macho, Manga blanca, San Diego, Manzano, Smith, Florida, Keitt, and Kent), limonene (cvs. Delicioso, Super Haden, Ordonez, Filipino, and La Paz), both terpenes (cv. Delicia), terpinolene (cvs. Obispo, Corazon, and Huevo de toro), and alpha-phellandrene (cv. Minin). Other qualitative and quantitative differences among the cultivars could be demonstrated.  相似文献   
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The objective of this study was to evaluate the efficacy and safety of several parenteral anesthetics in blue crabs (Callinectes sapidus). Thirty-one animals were administered one or more of the following drugs by injection into the hemolymph (i.v.) through an arthrodial membrane: etomidate, ketamine, lidocaine, pentobarbital, propofol, tiletamine-zolazepam, xylazine, and ketamine-xylazine. A subset of crabs received intracardiac ketamine. Etomidate had no effect. Lidocaine effects were ultrashort (<3 min). Pentobarbital had prolonged inductions (2 min) and often caused violent excitement and poor anesthesia. Propofol induced light anesthesia accompanied by distress and limb autotomy. Inductions with ketamine, xylazine, tiletamine-zolazepam, and ketamine-xylazine were usually fast (<60 sec). Their anesthetic effects were generally very short (5-10 min) but predictable, smooth, and with good muscle relaxation. The latter two protocols induced a deep plane of anesthesia more consistently but also more significant bradycardia. Intracardiac ketamine injection was fatal in four of five crabs. In conclusion, the anesthetic protocols were considered unsuitable for prolonged anesthesia. However, if very short-term anesthesia is desired, then tiletamine-zolazepam or ketamine-xylazine is recommended. Further studies are indicated to identify a safe anesthetic protocol of longer duration in C. sapidus as well as in other crab species.  相似文献   
36.
A 4-mo-old, 185-kg male giraffe (Giraffa camelopardalis reticulata) was presented due to stifle effusion and lameness of 3-wk duration. Radiographs revealed a fracture of the extensor fossa of the lateral trochlear ridge of the femur at the origin of the peroneus tertius. Under anesthesia, dysfunction of the reciprocal apparatus was documented by flexing the stifle while the tarsus remained extended. An avulsion fracture of the origin of the peroneus tertius and extensor digitorum longus muscle was diagnosed. An exploratory arthroscopy of the femorotibial joint was followed by arthrotomy to excise the large bone fragment from its soft tissue attachments. Because of the fractious temperament of the animal, postoperative care was restricted to stall rest for 3 mo, and no postoperative complications arose. Only a mild residual lameness remained by 6 mo after surgery.  相似文献   
37.
This study compared co-feeding zooplankton (ZP, mixed copepods and mysids) and formulated diets (FD) supplemented with L-tryptophan (TRP) on the survival and growth of grouper and sea bass fry nursed in brackish water ponds. Grouper (84 fry m?3) and sea bass (150 fry m?3) were reared for 30 days and 60 days, respectively, in net cages within two separate 743 m2 nursery ponds. Five treatments (with three replicates each) were compared (P < 0.05): FD-1 = ZP + basal FD (no added TRP, but containing 0.29% endogenous TRP); FD-2 = ZP + (FD 0.58% TRP); FD-3 = ZP + (FD 1.22% TRP); FD-4 = ZP + (FD 2.50% TRP); and FD-5 = minced fish (Sardinella sp.) + basal FD (no additional TRP). TRP supplementation in grouper diets produced no significant affect on growth but increased survival at rates of 0.58% and above. TRP supplementation at 2.5% (FD-4) produced significantly better sea bass growth than other diets but had no affect on survival. Zooplankton improved both survival and growth in both grouper and sea bass juveniles compared to the minced fish diet, and may be a practical and lower cost alternative to indoor nursing.  相似文献   
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The wide use of pesticides in modern agriculture may cause side effects on the non-target microflora. Data on the fungicide Tebuconazole effects on Azospirillum-wheat association are scarce. We analyzed the effects of Tebuconazole on: (a) Azospirillum brasilense Sp245 growth in pure culture, (b) A. brasilense Sp245 colonization of Triticum aestivum cv ProINTA Oasis roots, (c) A. brasilense Sp245-inoculated seedlings growth under normal and water stress conditions in the presence of 20% polyethylene glycol 8000. Seeds were separated in Tebuconazole-free and Tebuconazole-treated lots. Inoculated and non-inoculated seedlings were grown in hydroponics in the dark at 20 °C for 72 h. Root surface, coleoptile length, fresh and dry (DW) weights in both tissues and diazotrophic bacterial most probable number in roots were determined. Water contents and shoot-to-roots DW ratio were calculated. Neither Azospirillum growth nor root colonization was affected by Tebuconazole. Under normal growth conditions most of the growth parameters analyzed, revealed a clear positive effect of A. brasilense on wheat seedlings up to 72 h treatments. The characteristic Azospirillum enhancing effects observed on roots remained unaltered by Tebuconazole. The present study shows that Tebuconazole is compatible with A. brasilense Sp245-wheat inoculation.  相似文献   
40.
New Forests - Cut stumps are the legacy of forest harvesting and allow for the estimation of carbon loss from the ecosystem. The objective of this study was to estimate aboveground carbon storage...  相似文献   
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