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41.
In a study of some of the factors that are believed to affect fruit-setting in Eichhornia crassipes under Sudan conditions, the average number of flowers per inflorescence was twelve (range 4–26) while the average number of capsules per inflorescence was 1·5 (range 0–16). The problem of low fruit-setting was suggested to be basically due to the ecological factor of high temperature and low relative humidity. The flowers were preponderantly meso-stylic with the long and short-stylic ‘races’ absent or very rare. Recherches stir la biologic d'Eichhornia crassipes (Mart.) Solms dans le Nil Dans une étude sur quelques-uns des facteurs que l'on suppose actifs sur la mise à fruits de l’Eichhornia crassipes. dans les conditions du Soudan le nombre moyen de fleurs par inflorescence fut de 12 (s'étendent de 4 à 26), cependant que le nombre moyen de capsules par inflorescence fut de 1,5 (s'étendant de 0 à 16). Le probléme de la faible mise à fruit suggere qu'elle pourrait etre due a des facteurs écologiques: température élevée et faible humidity relative. Les fleurs étaient en majorité meso-stylées, les races à long style ou à style court étaient absentes ou tres rares. Generative Vermehrung von Eichhornia crassipes (Mart.) Solms. im Nil In einer Untersuchung über einige Faktoren, von denen angenommen wird, dass sie die Fruchtbildung von Eichhornia crassipes unter sudanesischen Bedingungen beeinflussen, war die durchschnittliche Anzahl von Blüten, 12 Blüten pro Inflorescenz (4–26), wáhrend die durchschnittliche Anzahl von Kapseln nur 1.5 Kapseln pro Inflorescenz war (0–16), Das Problem der geringen Fruchtausbildung wurde folgenden okologischen Faktoren zugeschrieben; hohe Temperatur und niedrige Luftfeuchtigkeit. Bei den Blüten wurden überwiegend Stempel miltlerer Länge gefunden, während die ‘Rassen’ kurzer und langer Stempel nicht oder nur sehr selten anzutreficn waren.  相似文献   
42.
Imazapyr owes its importance in Morocco to its success in controlling the perennial weed Solanumelaeagnifolium Cav., which infests the Tadla area. Persistence and mobility of imazapyr has been studied in two Moroccan soils from the Rabat area, with differing organic matter content (red and organic soils), under laboratory conditions at 75% of their field capacities and 25–28 °C. Residue analysis was performed on the basis of a bioassay test using lentil (Lens culinaris Medic.) as indicator species. The residual activity of imazapyr accounted for 69%, 25%, 50% and 62%, 46%, 66% of the initial activity for the red and organic soils at 1, 5 and 10 mg L?1 respectively. The half-lives varied between 25 and 58 days for the red soil and 55 and 58 days for the organic soil. In the organic soil, imazapyr was highly mobile under the irrigation regime applied. Most of the activity was found in the first 3 × 75 mL of the effluents. A following biotest with the leached soil showed low remaining residual activity.  相似文献   
43.
Introns are generally highly polymorphic regions within genes and were proven to be of great interest for discriminating among phylogenetically-close Phytophthora species. Phytophthora ramorum and P. fragariae are considered as quarantine pathogens by the European Union and accurate detection tools are therefore necessary for their monitoring. From introns located in different single copy genes (GPA1, RAS-like, and TRP1), we developed a series of PCR primers specific to P. ramorum and P. fragariae. The specificity of these primers was successfully checked with a wide collection of Phytophthora isolates and a protocol was developed to detect both pathogens directly in infected plant tissues. These genes should be of particular interest for the development of additional species-specific detection tools within the Phytophthora genus.  相似文献   
44.
Sugarcane yellow leaf virus (ScYLV) is distributed worldwide and has been shown to be the cause of the disease sugarcane yellow leaf syndrome (YLS). This study was an investigation of the transmission and spread of ScYLV in Hawaii. Several aphids are known to transmit the virus, but investigation of infestation and transmission efficiency showed Melanaphis sacchari to be the only vector important for field spread of the disease. The initial multiplication of ScYLV in a virus-free plant occurred exclusively in very young sink tissues. When a single leaf was inoculated on a plant, that leaf and all older leaves remained virus-free, based on tissue-blot immunoassay, whereas meristems and all subsequently formed new leaves became infected. Therefore, only after those leaves which had already developed before inoculation had been shed, did the complete plant contain ScYLV. Spread of the viral infection to neighbouring plants in the plantation fields via aphids was relatively slow and in the range of a few metres per year. No indication of long-distance transfer could be seen. This indicates that it may be possible to produce and use virus-free seed cane for planting of high-yielding but YLS-susceptible cultivars.  相似文献   
45.
The successful management of hepatic diseases of dogs and cats requires an understanding of hepatic metabolism and nutritional processes. General aspects of dietary therapy for hepatic diseases are described, along with specific recommendations for the promotion of tissue regeneration. Special considerations, including the role of diet in encephalopathy, hepatic lipidosis, and copper-associated hepatic toxicosis, are also discussed.  相似文献   
46.
47.
The present study was performed to evaluate the effect of vitamin C on the performance of Nile tilapia (Oreochromis niloticus) affected by the usage of engine oil. A total of 120 tilapia fish were randomly divided into four equal groups according to dietary treatments applied for 3 weeks: group I (control); group II was exposed to engine oil; group III was exposed to engine oil and supplemented with vitamin C: and group IV was fed only a diet supplemented with vitamin C. According to our results, the group exposed to engine oil (II) showed an induced elevation of kidney function parameters, an upregulation of CYP1A1 mRNA expression level, a reduction in antioxidant status (SOD, GSH) and severe abnormal histological and ultra‐structural changes in the head kidney, trunk kidney and muscle tissue. Supplementation of group III with vitamin C ameliorated the toxic effect induced by engine oil through improvement of kidney function parameters, elevation of the antioxidant status of tissue and improvement of the histological images of renal and muscle tissues. In conclusion, vitamin C has the ability to ameliorate engine oil oxidative stress toxicity in Nile tilapia.  相似文献   
48.
Objective-To determine associations between serum concentrations of omega-3 polyunsaturated fatty acids or body condition and serum concentrations of adiponectin, leptin, insulin, glucose, or triglyceride in healthy dogs. Animals-62 healthy adult client-owned dogs. Procedures-Body condition score and percentage of body fat were determined. Blood samples were collected after food was withheld for 12 hours. Serum was harvested for total lipid determination, fatty acid analysis, and measurement of serum concentrations of adiponectin, leptin, insulin, glucose, and triglyceride. Associations between the outcome variables (adiponectin, leptin, insulin, glucose, and triglyceride concentrations) and each of several variables (age, sex, percentage of body fat, and concentrations of total lipid, α-linolenic acid, eicosapentaenoic acid, docosapentaenoic acid, and docosahexaenoic acid) were determined. Results-Serum concentrations of docosapentaenoic acid were significantly positively associated with concentrations of adiponectin and leptin and negatively associated with concentrations of triglyceride. Serum concentrations of α-linolenic acid were significantly positively associated with concentrations of triglyceride. No significant associations were detected between serum concentrations of eicosapentaenoic acid or docosahexaenoic acid and any of the outcome variables. Percentage of body fat was significantly positively associated with concentrations of leptin, insulin, and triglyceride but was not significantly associated with adiponectin concentration. Age was positively associated with concentrations of leptin, insulin, and triglyceride and negatively associated with concentrations of adiponectin. Sex did not significantly affect serum concentrations for any of the outcome variables. Conclusions and Clinical Relevance-Docosapentaenoic acid may increase serum concentrations of adiponectin and leptin and decrease serum triglyceride concentration in healthy dogs.  相似文献   
49.
50.
A 60‐day feeding trial was conducted to determine the effects of copper nanoparticles (Cu‐NPs) and vitamin C (VC) on red sea bream. Besides the control diet (D1), six diets were supplemented with Cu‐NPs and VC [0/800 (D2), 0/1,000 (D3), 0/1,200 (D4), 2/800 (D5), 2/1,000 (D6) and 2/1,200 (D7) mg Cu‐NPs/VC per kg]. Cu‐NP was a significant factor on final weight (FBW), weight gain (WG) and specific growth rate (SGR), feed intake (FI), feed (FER) and protein efficiency ratios (PER), protein gain (PG) and protein retention (PR), body protein and lipid contents, protease (PA) and bactericidal activities (BA) and tolerance against stress (LT50%) (< .05). In addition, BA and LT50% were significantly affected by either Cu‐NPs or VC (< .05). Fish fed Cu‐NPs or/and VC‐supplemented diets showed higher FBW, WG, SGR, PG, PR, FI, PA, LA and BA values when compared with the control group (< .05). FER, PER and body lipid content were significantly enhanced in D4, D5, D6 and D7 groups; meanwhile, body protein and LT50% were significantly enhanced in D5, D6 and D7 groups when compared with D1 group (< .05). In conclusion, dietary Cu‐NPs or/and VC improved growth and health of red sea bream.  相似文献   
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