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71.
Experiments were carried out with 24 pregnant cows and their calves. The cows were divided in 2 equal groups. One of these received a supplement of animal fat additional to the feed from 4 weeks a. p. to 6 weeks p. p. Apart from clinical examinations following laboratory investigations in the blood were performed: hematological parameters, cholesterol, lipids, free fatty acids, ketone bodies, protein, glucose, bilirubin, transaminases, alkaline phosphatase, Ca, Mg, P, K, Na, Cl. The addition of fat to the feed of cows influenced the energy metabolism of the cows, the body weight of the newborn ones and some hematological parameters (incl. protein) of the calves positively.  相似文献   
72.
The aim of the study was to investigate the effects of supplementation of a microencapsulated blend of tributyrin and lactitol (TL) to a standard European (EU) diet without antibiotic growth promoters on intestinal metabolism and mucosa development of weaned piglets and to compare it with a standard US diet containing animal proteins, zinc oxide, copper sulfate, and carbadox. Ninety piglets weaned at 21 d were divided into 3 dietary groups consisting of 5 replicates each: 1) US diet supplemented with 55 mg/kg of carbadox, and 2.5% each of plasma proteins and spray-dried blood cells in the first phase, 3,055 mg/kg of Zn in the first and second phases, and 180 mg/kg of Cu in the third phase; 2) EU diet based on vegetable proteins and no antibiotics; and 3) the same EU diet supplemented with 3,000 mg/kg of microencapsulated TL. The study was divided into 3 phases: 0 to 7, 8 to 21, and 22 to 35 d. On d 7, 21, and 35, animals were weighed, and feed consumption and efficiency were determined. On d 14 and 35, one pig per pen was killed, and the intestinal contents and mucosa from the proximal, middle, distal jejunum and the ileum were sampled. Intestinal wall sections were fixed for histological analysis, and intestinal content was used for VFA, ammonia, and polyamine analysis. Throughout the study (d 0 to 35), the US diet had greater ADG and ADFI than the EU diet (P < 0.05). The EU diet supplemented with TL tended to have 11% greater ADG (P = 0.17). Feeding the EU diet caused a reduction in proximal and middle jejunum villi length by 10% (P < 0.05) and an increase in crypt size in proximal jejunum (P < 0.05) compared with the US diet, probably due to an increased rate of cell loss and crypt cell production. The TL supplementation resulted in longer villi along the jejunum and less deep crypts in the proximal jejunum (+15.9 and -8.9%, respectively; P < 0.05) than the unsupplemented EU diet. The TL diet increased the concentrations of cadaverine and putrescine in the small intestine (P < 0.05) and seemed to increase cadaverine, histamine, putrescine, and spermine in the large intestine by 1.5- to 10-fold compared with the US or EU diet. In conclusion, although the US diet had a greater effect on growth performance and mucosal trophic status than the EU diets, the supplementation with slowly released TL seemed to be an effective tool to partially overcome the adverse effects of vegetable protein diets.  相似文献   
73.
74.
1. The aim of the study was to investigate the effects of feeding fast growing turkeys with differentiated dietary calcium (Ca) content, and the partial replacement of vitamin D3 in the feed with 25-hydroxycholecalciferol (25(OH)D3), on skeletal properties.

2. One-day-old Big-6 male turkeys (n?=?1008) were randomly divided into 4 groups, and two subgroups were created within each group. The groups were differentiated with 4 levels of Ca provision in the feed, namely 85% of the National Research Council (NRC) recommendation (Group Ca1); 95% as above (Group Ca2); 105% as above (Group Ca3); and 115% as above (Group Ca4). The first subgroup received the recommended dosage of cholecalciferol (vitamin D3 subgroup) in the feed, while in the second subgroup (Hy-D subgroup), half of the dosage of cholecalciferol was replaced with 25(OH)D3. At the ages of 4, 8, 12 and 20 weeks, 7 turkeys from each subgroup were randomly selected and killed to obtain the right tibia for densitometric, geometric and mechanical analyses.

3. This study showed advantageous effects of increased calcium supply in the diet on skeletal system properties, that were increased and produced the most desirable traits in turkeys receiving 95%, 105% and 115% of the NRC calcium recommendation. Benefits resulting from administration of 25(OH)D3 in the diet were also obtained in the skeletal formation of turkeys, and the most advantageous effects were present in the group receiving 105% of recommended dietary Ca.

4. Effects on the metabolic response of the skeleton of turkeys to manipulation of dietary calcium content and vitamin D3 source were the most evident in the groups between 4 and 12 weeks of life, and demonstrated a limited ability to induce a positive influence on bone properties at advanced stages of the production cycle by alteration of these dietary factors.  相似文献   

75.
76.
The experiment was carried out with ducklings fed-control feed mixture (Met level 0.3%) and mixtures supplemented with dl-methionine at the dose of 0.03 (II); 0.07 (III) 0.12 (IV) and 0.18% (V). In 5 h post-hatch (12 birds) and on days 3, 4, 6 always 18 birds were taken out from each treatment and killed, then the yolk sac (YS) and intestine were removed. The weight and chemical composition of YS residues (in them also amino acids) were analysed. Moreover on days 1, 3, 4 and 6, the amino acid pattern of YS residual protein was elaborated as well as length and weight of intestine were recorded. Increased doses of supplemental Met improved body weight gain after 4 days of ducklings life. All determined parameters were not affected by treatment. Development of intestines, yolk sac weight and yolk sac composition (DM, fat, protein, amino acid composition) changed with age; however, without any clear effect from dietary methionine level. No differences between sex and analysed parameters were stated.  相似文献   
77.
78.
Various types of hypospadias and methods of surgical treatment of this anomaly in 6 dogs was described in this article. Methods of surgical treatment were set up individually for each case and depended on the type of hypospadias and coexisting anomalies. Shortening of the penis was performed in two dogs, amputation in three cases and an urethral reconstruction in one patient. Castration was performed in three cases. Persistent frenulum of the prepuce was found in two dogs. Additionally three patients were submitted to the plastic surgery of the prepuce anomalies. In one dog, the loose and free falling part of the prepuce was suspended and attached to the abdominal integument according to the original own method. In all dogs, uncomplicated wound healing was observed. Surgical procedures resulted in improved cosmesis with reducing clinical signs of hypospadias and other coexistent anomalies.  相似文献   
79.
The aim of the study was to estimate nutritional and physiological consequences of combined supplementation of rat casein diets with a strongly oxidized mixture of fats and extract of polyphenols from chokeberry. The experiment was conducted on 80 young Wistar rats divided into 8 groups. The animals were fed diets supplemented with 8% of fresh or oxidized fats and 0.4, 0.8 and 1.2% of polyphenol extract together. Addition of the oxidized fats caused significant reduction in animal growth without a decrease in nitrogen digestibility. On the other hand, the extract of polyphenols suppressed nitrogen utilization; animal growth was however similar to the control group. Analysis of the variance showed negative influence of the oxidized fats on cholesterol and triacyloglycerol concentration in the blood of the experimental animals. Increased activity of both aminotransferases in the blood of rats fed diets containing the oxidized fats indicated on liver malfunction. There was no effect of the experimental factors on the antioxidant status of the blood, but a dose-dependent reduced content of malonylodialdehyde in the blood of rats fed diets supplemented with the extract of polyphenols suggested that the extract had a preventive effect against prooxidative activity of the oxidized fats.  相似文献   
80.
The clinical form of the protothecosis in animals is most commonly observed in countries with a warm and moist climate, only a few reports describing cases of this infection in cooler areas of the word exist. In the case of large bowel infection in dogs, organisms colonise the lamina propria and submucosa causing severe necrotizing ulcerative or haemorrhagic enterocolitis. In this report the intestinal form of protothecosis in 1.5-year-old, male, mongrel dog with chronic hemorrhagic diarrhoea is described. History revealed that the dog spent some time in the countryside and afterwards diarrhoea with fresh blood appeared. The results of morphological and biochemical blood analysis were normal and stool examination did not reveal the presence of parasites. Treatment with anti-inflammatory doses of prednisone, metronidazole and enrofloxacin followed by sulphasalazine resulted in a short period of improvement, but was followed by deep deterioration of animal status. Because of the relapse diagnostic laparotomy was performed and tissue samples of the colon and jejunum were obtained for histopathology. On the basis of the clinical signs, exploratory laparotomy findings and histopathology the diagnosis of canine intestinal prototecosis was made and medical treatment was recommended.  相似文献   
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